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Chemical engineering education

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Title:
Chemical engineering education
Alternate Title:
CEE
Abbreviated Title:
Chem. eng. educ.
Creator:
American Society for Engineering Education -- Chemical Engineering Division
Place of Publication:
Storrs, Conn
Publisher:
Chemical Engineering Division, American Society for Engineering Education
Publication Date:
Frequency:
Quarterly[1962-]
Annual[ FORMER 1960-1961]
quarterly
regular
Language:
English
Physical Description:
v. : ill. ; 22-28 cm.

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Subjects / Keywords:
Chemical engineering -- Study and teaching -- Periodicals ( lcsh )
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serial ( sobekcm )
periodical ( marcgt )

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Citation/Reference:
Chemical abstracts
Additional Physical Form:
Also issued online.
Dates or Sequential Designation:
1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-
Numbering Peculiarities:
Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.
General Note:
Title from cover.
General Note:
Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

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University of Florida
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All applicable rights reserved by the source institution and holding location.
Resource Identifier:
01151209 ( OCLC )
70013732 ( LCCN )
0009-2479 ( ISSN )
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TP165 .C18 ( lcc )
660/.2/071 ( ddc )

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Chemical Engineering Documents

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CEE

VOIJIMF, il NUMBI:R I WINTE'R 1998

Featuring ...
Arvind
Varma
ol'Noll-c Dame
plus articles on









(1/ld chemical ('111"hiccl-1/1", a/
Wayne State University







Visit us
on
our new
web page
at

http://che.ufl.edu/cee/












EDITORIAL AND BUSINESS ADDRESS:
Chemical Engineering Education
Department of Chemical Engineering
University of Florida Gainesville, FL 32611
PHONE and FAX: 352-392-0861
e-mail: cee@che.ufl.edu
Web Page: http://che.ufl.edu/cee/

EDITOR
T. J. Anderson

ASSOCIATE EDITOR
Phillip C. Wankat

MANAGING EDITOR
Carole Yocum

PROBLEM EDITORS
James O. Wilkes and Mark A. Burns
University of Michigan
LEARNING IN INDUSTRY EDITOR
William J. Koros
University of Texas, Austin

-PUBLICATIONS BOARD
CHAIRMAN *
E. Dendy Sloan, Jr.
Colorado School of Mines

PAST CHAIRMEN *
Gary Poehlein
Georgia Institute of Technology
Klaus Timmerhaus
University of Colorado

MEMBERS
Dianne Dorland
University of Minnesota, Duluth
Thomas F. Edgar
University of Texas at Austin
Richard M. Felder
North Carolina State University
Bruce A. Finlayson
University of Washington
H. Scott Fogler
University of Michigan
David F. Ollis
North Carolina State University
Angelo J. Perna
New Jersey Institute of Technology
Ronald W. Rousseau
Georgia Institute of Technology
Stanley L Sandler
University of Delaware
Richard C. Seagrave
Iowa State University
M. Sami Selim
Colorado School of Mines
James E. Stice
University of Texas at Austin
Donald R. Woods
McMaster University


Chemical Engineering Education

Volume 32 Number 1 Winter 1998


> EDUCATOR
2 Arvind Varma, of Notre Dame, Anne Kolaczyk

> DEPARTMENT
8 Wayne State University

> CURRICULUM
14 Chemical Engineering and the Other Humanities, J.M. Prausnitz
52 An Introductory ChE Course for First-Year Students,
Kenneth A. Solen, John N. Harb
58 Freshman Design Projects in the Environmental Health and Safety Department,
Ronald J. Willey, John M. Price
62 Innovative Ways of Teaching Polymerization Reactor Engineering: Exchanging
Information Between the University and Industry,
Jodo B.P. Soares, Alexander Penlidis, Archie E. Hamielec
84 Just a Communications Course? Or Training for Life after the University,
Guido Bendrich

> CLASSROOM
20 COMET: An Open-Ended, Hands-On Project for ChE Sophomores,
Mark R. Prausnitz
24 Animal Guts as Ideal Reactors: An Open-Ended Project for a Course in Kinetics
and Reactor Design, Eric D. Carlson, Alice P. Gast
36 Helpful Hints for Effective Teaching, Robert H. Davis
68 Practical Hints for Gathering Information, Saidas M. Ranade
82 Combustion Synthesis and Materials Processing: Student Exercises,
Daniel E. Rosner

> LOOKING BACK
72 Advice from an Old-Timer, W. Dan Maclean

> LEARNING
30 Toward Technical Understanding: Part 3. Advanced Levels, J.M. Haile

> LABORATORY
40 Experiments Illustrating Phase Partitioning and Transport of Environmental
Contaminants, Susan E. Powers, Stefan J. Grimberg
76 An Undergraduate Experiment on Adsorption, Shamsuzzaman Farooq

> RANDOM THOUGHTS
46 Ships Passing in the Night, Richard M. Felder

> LEARNING IN INDUSTRY
48 Make Summer Internship a Learning Experience, Gary S. Huvard

> 13 Letter to the Editor
> 13,29 Book Reviews


CHEMICAL ENGINEERING EDUCATION (ISSN 0009-2479) is published quarterly by the Chemical Engineering
Division, American Society for Engineering Education, and is edited at the University of Florida. Correspondence
regarding editorial matter, circulation, and changes of address should be sent to CEE, Chemical Engineering Department,
University of Florida, Gainesville, FL 32611-6005. Copyright 1998 by the Chemical Engineering Division, American
Society for Engineering Education. The statements and opinions expressed in this periodical are those of the writers and
not necessarily those of the ChE Division, ASEE, which body assumes no responsibility for them. Defective copies replaced
if notified within 120 days of publication. Write for information on subscription costs and for back copy costs and
availability. POSTMASTER: Send address changes to CEE, Chemical Engineering Department., University of Florida,
Gainesville, FL 32611-6005. Periodicals Postage Paid at Gainesville, Florida.


Winter 1998








educator




Arvind




Varma




of Notre Dame


ANNE KOLACZYK*
University of Notre Dame Notre Dame, IN 46556
When Arvind Varma was awarded the University of Notre Dame's College of
Engineering Outstanding Teacher of the Year Award for 1990-91, his
students praised him as "an excellent teacher both in and out of the classroom,"
and said he showed a "great interest in his students" and was "willing to be a friend and a
mentor." They cited his extensive availability, saying it was "a rare and valuable opportunity
to work with a person with such great character and work ethic. He will be the professor whom
we will vividly remember twenty years from now, and his influence will be
matched by few in our lifetime."
The award and the citation that accompanied it were gratifying to Arvind, who
believes that the most important thing a teacher can be is a good model for the
students. "Whether you are in the classroom or doing research, you must always
do things the right way," he says. "A teacher should not just impart information,
but should also teach students how to think, how to live. You need to teach
critical analysis, so that they are able to ask questions, to make decisions on their
own. You can rely on people and other sources for information, but you should
be able to analyze on your own to make decisions." That ability to analyze is
what he hopes he has taught his students.
Carmo J. Pereira, a former student who is now a Principal Consult-
ant at DuPont Engineering, believes he learned that ability as Varma's
student. "When I first met Professor Varma, he had just arrived at
Notre Dame after two years in industry. I am a practicing reaction
engineer today in large part due to him. His love for reaction engineer-
ing, his great attention to detail, and his dedication to the profession

* Ann Kolaczyk is Publications Editor in the College of Engineering at the
University ofNotre Dame. This article was written with assistance from the
faculty of the Department of Chemical Engineering.
@ Copyright ChE Division ofASEE 1998


A Asa
young
faculty
member
in the late
1970s,


I


and

4 As a
graduate
student in
the late 1960s,
and
4 As an
undergraduate
student in the
mid-1960s.

Chemical Engineering Education










[Arvind] says,

"A teacher should not just impart

information, but should also teach students how to

think, how to live. You need to teach critical analysis, so that

they are able to ask questions, to make decisions on their own.


are truly contagious! I have been greatly influenced by Pro-
fessor Varma's desire to excel, and I have attempted to
follow his example."
Another former student, Bala Subramaniam (now a chaired
professor of chemical and petroleum engineering at the Uni-
versity of Kansas in Lawrence) says, "Professor Varma's
research accomplishments are well known and recognized.
What is probably not as well known is that Professor Varma
is also a gifted teacher with exemplary dedication and excel-
lence in educating his students." He adds, "His lectures are
intellectually stimulating, characterized by careful prepara-
tion and energetic delivery. Professor Varma brought to his
class the latest research developments from his program as
well as others. This allows students to gain a better apprecia-
tion of creativity, which in turn inspires them to be creative.
He is very accessible to his students, and whenever interact-
ing with them either in or outside class, he creates an atmo-
sphere that promotes the students' desire to learn and to
excel. Personally, these experiences have helped shape my
teaching philosophy and methods to a great extent."
Arvind was born in Ferozabad, U.P., India, the fourth of
seven children. He had always been a good student and, due
to double promotions, was only 15 years old when he gradu-
ated from high school in 1962. This made choosing a college
difficult because most of the schools in India had age restric-
tions and required incoming freshmen to be at least 17 or 18
years old. The Indian Institutes of Technology were just
starting then and were already prestigious, but they too had
age restrictions.
Arvind had done well in chemistry and mathematics in
high school and was looking at chemical engineering on the
advice of his father, who was a civil engineer working in
government service. When Arvind learned that Panjab Uni-
versity in Chandigarh (one of the schools without an age
restriction) had recently started a chemical engineering pro-
gram with American collaboration, he applied there and was
accepted. It was a unique situation in that the engineering
college affiliated with the school had the other engineering
disciplines on its own campus, but the new chemical engi-
neering department was autonomous and was housed on the
main university campus.
The chairman of the department was Professor B. Ghosh.
He was young, outstanding, and bright. Recently returned
Winter 1998


from Carnegie Tech (now Carnegie-Mellon), he was a
thoughtful teacher, and through him, Arvind was exposed to
a more American style of teaching. Professor Ghosh's classes
were more open and discussion-based, and he didn't insist
on such a strict student/teacher division. It was at this time
that teaching as a profession began to appeal to Arvind.
"The idea of standing up in front of class, explaining
things, talking about what you knew, was very appealing to
me," Arvind says. "I decided during my freshman year to be
a college teacher."
When he finished his undergraduate work, Arvind was
still only 19 years old and was anxious to come to North
America for his graduate work. His parents weren't too keen
on his leaving the country, but he was ready for new chal-
lenges. He applied to a few places in Canada and eventually
chose the University of New Brunswick, where he would
have the chance to work with Frank Steward in combustion
of solid fuels.
At the University of New Brunswick he was exposed to
even more of the Western style of teaching, further convinc-
ing him that he wanted to be an educator. But in his second
year of graduate school, Frank Steward took a UNESCO
appointment, and Arvind decided to change schools to pur-
sue his doctorate. The University of Minnesota was rated
very highly then, as it is now, and he was accepted and
awarded an assistantship there.
During the late 1960s and 1970s, the University of Minne-
sota was an exciting place to be. A great deal of research was
being done in the area of analysis of chemical engineering
systems, particularly mathematical analysis. This effort was
led by Professor Neal Amundson, who was department head
and also Arvind's thesis advisor. Amundson had gathered
together a top-notch faculty, many of whom had degrees in
the sciences or math rather than in chemical engineering. At
this same time, the Mining and Metallurgical Engineering
Department was closing down and materials science was
brought into chemical engineering. This mixture produced
an emphasis on the fundamental scientific aspects of chemi-
cal engineering-the engineering science approach-in which
there is an application of surface chemistry, biology, math-
ematics, and physics to chemical engineering problems. This
mixture of disciplines is more common now, especially in
research groups, but it was very unusual at that time.
3










At the University of Minnesota, Arvind was influenced
greatly by both Professor Neal Amundson and Professor
Rutherford Aris. Besides being an innovative leader,
Amundson was a brilliant teacher and researcher. He taught
a two-hour course on math-
ematical methods in chemical
engineering twice a week and
did all his complex computa-
tions on the chalkboard without
any notes. Aris was a great
scholar and writer, very fluent
with words and widely pub-
lished. He was a soft-spoken,
kind gentleman. Where
Amundson was Arvind's model
of an innovator and teacher, Aris
was his model of a scholar.
In 1971, Arvind married his
wife Karen, then a senior ma-
joring in biology at the Univer- Arvind with two people
sity of Minnesota. A few days development-Neal A
after getting married, they spent Aris-at Aris' retire
six weeks in India, meeting his
family and seeing the country. Arvind received his PhD in
1972. His thesis on "Analysis of Tubular Reactor Multiple
Steady States and Their Stability" generated a number of
articles. After he was awarded his doctorate, Arvind stayed
on at the University of Minnesota as a temporary assis-
tant professor for one year, doing limited teaching while
working on research. During this period he got to know
Professors Amundson and Aris even better, as well as a
number of other faculty members.
Arvind firmly believed that to be a good teacher, one
needed industrial experience (as Amundson and Aris had),
so when he was ready to leave the University of Minnesota
he interviewed both in academia and in industry. After con-
sidering offers from a number of sources, he went to work as
a senior research engineer for Linde Research of Union
Carbide in Tarrytown, New York, where he did research in
gas separations.
The research at Union Carbide was very different from
that which Arvind had done for this thesis, but that was part
of its appeal since it meant his experience would become
even broader. He was hired as a part of the Process Research
Group, a newly formed unit that was looking into novel
methods of gas separation processes. Some of the projects
that he worked on in their initial conceptual stages were a
new process for breathing oxygen on aircraft, a new type of
cryogenic insulation using thin evacuated glass microspheres,
a zeolite slurry-based continuous gas separation process, and
a parametric pumping system for an air separation process
for producing oxygen for medical purposes. A number of
these projects subsequently became commercial successes.


wh
1mu
men


During this period, Karen and Arvind also became proud
parents of their first child, Anita, born in 1974. Karen had
worked as a laboratory assistant in microbiology since her
graduation two years earlier, but now gave up her career to
become a full-time mother.
In 1975, after two years at
Union Carbide, Arvind received
an offer from the University of
Notre Dame. The chemical en-
gineering department there was
well known due to the work in
catalytic reaction engineering
done by James Carberry and
Ernest Thiele (who was no
longer at Notre Dame but who
had added greatly to the stature
of the department) as well as
the work in thermodynamics and
phase equilibria being done by
o shaped his academic James Kohn and Kraemer Luks.
idson and Rutherford Also, the department's chair-
atfestivities in 1996 man, Julius Banchero, was a
well-known educator who was
supportive of young faculty. Arvind decided to make the
change to academia and was further convinced that the deci-
sion was a good one when Roger Schmitz came from the
University of Illinois in 1979 to take over as department
chair upon Banchero's retirement. Arvind quickly progressed
through the ranks, becoming a full professor in 1980, the
same year that his younger daughter, Sophia, was born.
In 1982, Arvind became department chair himself when
Roger Schmitz went on to become engineering dean. Al-
though Arvind was young for the position, he had definite
ideas he was eager to implement and, under his leader-
ship, the department grew. During his tenure, Mark
McCready (the current department chair), David Leighton,
and Hsueh-Chia Chang (who served as chair after Arvind)
all joined the faculty.
When he was chair, Arvind chose to teach the "Introduc-
tion to Chemical Engineering" course himself because he
thought it was important for the chair to be visible to the new
students in the department. He also brought team teaching to
the undergraduate labs, with part of the faculty teaching the
fall semester lab for seniors and another part teaching the
spring lab for juniors. This had the dual effect of making it
more interesting for the faculty to teach and encouraging
camaraderie as they worked together. It was also good for
students to have contact with a number of faculty members.
The senior design course is also team taught, so every mem-
ber of the faculty instructs in one of these three courses
every year. All three courses have written and oral reports
due at the end of the semester. By implementing his ideas,
Arvind helped to create an atmosphere of high standards for
Chemical Engineering Education









teaching and research.
Mark McCready, chair of the department, notes another
aspect of Arvind's leadership. "While Arvind is well known
for his mentoring of graduate students and his efforts to
enhance these activities campus wide, he has also mentored
a number of current faculty at Notre Dame. He provided a
great deal of guidance to me during my first few years here.
He helped with proposal and paper writing, encouraged my
participation in departmental committees, and made sure
that my views were heard. His efforts greatly enhanced my
development as a junior faculty member."
In order to devote full time to teaching and research,
Arvind decided to leave the department chair position in
1988. Within a few months of this decision, he was named
the first occupant of the Arthur J. Schmitt endowed chair
professorship, a position he still holds.
All of Arvind's research involves undergraduate, gradu-
ate, and post-doctoral students, true to his vision of an edu-
cator. When he was awarded the 1997 Burs Graduate School
Award from the University of Notre Dame this past May, the
citation noted, in part, that he is "a quintessential professor
who excels in all phases of academic life and for whom there
is no boundary between teaching and research."
In his twenty-three years at Notre Dame, twenty-seven
students have completed their doctoral dissertations under
his direction, and several more are currently in progress.
Every dissertation has resulted in coauthored publications in
leading journals and typically in one or more paper presenta-
tions at technical meetings. One of his students, Jean-Pascal
Lebrat received the 1993 Graduate School Award in Engi-
neering in recognition of the quality of his dissertation re-
search. Furthermore, largely through Arvind's efforts in coun-
seling and mentoring, his former students have been very
successful professionally in both industry and academia. Of
his former PhD and post-doctoral students, eighteen are in
academic positions at institutions around the world.
"As a mentor, Professor Varma led and taught by ex-
ample. His enthusiasm for his research program was infec-
tious and evident during the weekly research group meet-
ings," Bala Subramaniam says.
Arvind's early research involved various topics in chemi-
cal and catalytic reaction engineering, including diffusion-
reaction in catalyst pellets, reactor modeling and optimiza-
tion, gas-liquid reactors, and three-way catalysis for auto-
motive exhausts. Beginning in the early 1980s, his focus was
mainly in two areas. One area was the optimal distribution of
catalyst in pellets, in which the problem addressed is "How
should a fixed amount of catalyst be distributed in a pellet to
optimize some specified performance index?" This problem
is common to all reactions that use supported catalysts. In
systematic and innovative theoretical and experimental work,
Arvind and his students have shown that the optimal distri-
Winter 1998


bution is a Dirac-delta function, i.e., the catalyst should be
deposited at a specific radial position within the pellet. He
has also developed experimental methods for preparing such
catalysts. This work has direct implications for rational cata-
lyst design and manufacture.
The other area of Arvind's research during this period was
parametric sensitivity and runaway in chemical reactors. In
certain regions of operating conditions, chemical reactors
exhibit parametric sensitivity whereby small changes in in-
put parameters lead to large changes in output variables.
This behavior is common to all exothermic reaction sys-
tems. Determining these regions is of substantial interest
because such behavior leads to deleterious reactor perfor-
mance. By original and penetrating analysis, confirmed by
experiments, Arvind and his research group have provided
rigorous and easily applicable criteria for identifying the
regions of parametric sensitivity and runaway for a variety
of reacting systems.
For the last six to eight years, Arvind's research has been
in the area of materials, specifically the combustion synthe-
sis of materials. This is a large research program for mecha-
nistic studies of combustion synthesis: What is the mecha-
nism by which advanced materials such as ceramics, inter-
metallics, and composites are synthesized by the novel tech-
nique called combustion synthesis? How does the reaction
occur? How is the product material formed? How can the
microstructure of the material be controlled as it is being
synthesized? Because the microstructure affects the proper-
ties of the material, by understanding the mechanism of the
reaction and how the microstructure is formed, Arvind hopes
to gain an understanding of the control over what the proper-
ties of the material are going to be. His funding for this
research is from NSF and NASA.
In the NASA program, Arvind is looking at effects of
gravity on combustion synthesis of materials. Both the NSF
and NASA programs have produced some unique results
and new research techniques. One such technique, produc-
ing promising results, is the high-speed microvideo record-
ing of the combustion wave front.
"We are able to expand the wave front through magnifica-
tion, using a long focus microscope attached to a high-speed
video camera," Arvind says. "We can increase the spatial
resolution up to 800 times and can record up to 10,000
frames per second."
Arvind and his students can watch just how the reaction is
occurring and can see many of the details of combustion
wave propagation, leading to a better understanding of how
the wave front propagates in heterogeneous reaction mix-
tures that are used for synthesizing advanced materials. They
have the only facility in the world for doing this and are at
the forefront of developing new techniques for understand-
ing how such reactions occur. Using this novel technique,
Arvind and his research group have identified new modes of









propagation that have never been witnessed before-they
call it a scintillating reaction wave. In recent work, they have
shown that in many instances, the reaction initiates ahead of
the wave front and sparks appear. They are the first precur-
sor of the main reaction that occurs a few milliseconds later.
Another direction of Arvind's current research is inor-
ganic membranes. With funding from the National Science
Foundation and from industry (primarily Union Carbide), he
is studying various types of inorganic membranes-both
metal composite membranes in which a thin (a few microns
thick), dense, metal film is deposited on a porous support, as
well as ceramic membranes with controlled pore size and
catalytic activity distributions. He and his students have
developed some novel techniques, such as the use of osmosis
in conjunction with electroless plating. Using this idea, they
have synthesized high-flux thin metal composite membranes
for both high temperature reaction and separation processes.
In his current research, Arvind is applying the principles
of chemical engineering and novel experimental techniques.
His approach of combining theory and experiments, and of
determining the influence of processing variables on the
resulting microstructure and the reaction mechanism and
extent, is having a strong impact on the materials synthesis
field. He is frequently the only, or one of only a few, chemi-
cal engineers invited to speak at conferences related to the
reaction synthesis of advanced materials. Examples include
the TMS Annual Meeting in 1991 and all four International
Symposia on Self-Propagating High Temperature Synthesis
held in the former USSR (1991), Honolulu (1993), China
(1995), and Spain (1997). His plenary lecture on the "Com-
bustion Synthesis of Advanced Materials" at the 1992 Inter-
national Symposium of Chemical Reaction Engineering has
received considerable acclaim and attention as a landmark
summary of research in this area. His forthcoming mono-
graph will update this work and has been praised already as
"the seminal review on combustion synthesis."
Arvind has published extensively in collaboration with
Massimo Morbidelli, now a chaired professor at ETH in
Zurich, Switzerland. Massimo came to Notre Dame in 1979
on a fellowship from Italy. He stayed only six months, but
wrote four papers while he was here and made a lasting
impression on Arvind, who felt that he had great potential
and encouraged him to get his advanced degree.
His influence made a difference to Morbidelli. "I decided
to come back for my PhD," Massimo recalls, "But since I
was a researcher at Politecnico de Milano, I could not do it on
a full-time basis. It was Dr. Varma who arranged (with the
help of the department chairman at that time, Dr. Roger Schmitz)
a semi-non-resident PhD program for me at Notre Dame."
Since then, Massimo and Arvind have written some forty
articles and two books together, making their collaboration
one of the longer standing ones in academia. Their textbook


Mathematical Methods in Chemical Engineering (Oxford
University Press) was published earlier this year, and Para-
metric Sensitivity in Chemical Systems (Cambridge Univer-
sity Press), written jointly with research associate Hua Wu,
was completed this past August and will be published early
next year as part of the Cambridge Series in Chemical Engi-
neering, of which Arvind is the founding editor.
"I have continued my collaboration with Dr. Varma for
almost twenty years now," Massimo says, "And I find it
always more exciting, although we have now evolved in
different research areas. But even recently, when after long
hours together, one in front of the other at the same table,
reviewing our math book when we finished it, I felt the same
sense of accomplishment as when we finished our first paper
in 1979. I really felt I did something to my best, without
saving energies. This was in fact the program that Dr. Varma
stated many years ago when starting the 'book adventure.
He'd told me, '. and at the end we will sit together, read
each page of the book, and leave there each word only if we
like it.' And it has been done. This is really a great teaching
for how to proceed in science, and I have seen this teaching
penetrating all my students who later came to work for
longer or shorter periods of time with Dr. Varma from Italy:
Alberto Servida, Roberto Baratti, Giacomo Cao, Hua Wu,
Marco Apostolo, and others.
"Professor Varma has made significant contributions to
reaction engineering," Carmo Pereira says. "His work on
optimizing catalyst intraparticle profiles and on high tem-
perature synthesis is seminal, and he has received many
honors for his work, including AIChE's prestigious
Wilhelm Award."
Arvind has also found time to serve the University of
Notre Dame as well as many professional organizations. In
1992, he was awarded a Special Presidential Award by the
University for his "indefatigable energy in research, writing,
and all activities that engage his sharp mind and for serving
simultaneously on a large number of university, college, and
departmental committees." He was a member of the
University's Executive Committee of the Academic Council
for three years, served on the Academic and Faculty Affairs
Committee of the Board of Trustees for three years, and was
chairman of the Task Force on Research Systems, as well as
other committees. He is a founding director of the Catalysis
and Reaction Engineering Division of AIChE, serving a
three-year term; a current member of the AIChE Awards
Committee, serving a five-year term; and has organized and
chaired numerous technical sessions at national and interna-
tional conferences.
"Professor Varma's well-balanced contributions in teach-
ing, research, and service are truly remarkable and make him
the consummate professional and excellent role model that
he is," Bala Subramaniam says. "The fact that several of his
students have gone on to assume successful careers in aca-
Chemical Engineering Education












Arvind and Karen, along with his research group
and their terrier Frankie, at a recent
get-together at their home. >





A family photograph in traditional Indian dress on
the occasion of older daughter Anita's marriage to
Ken (also a chemical engineer) in May of 1997.
On the left is younger daughter Sophia,
currently a high school senior. V


demia and in major companies is a testament to his excellent
training and positive influence on his students."
Roger Schmitz, Keating-Crawford Professor of Chemical
Engineering at Notre Dame, has worked with Arvind for
eighteen years and says, "I find it difficult to identify Arvind's
strongest points because he excels in virtually every respect
in his professional and personal life. Few individuals can
match the combination of traits-dedication to academic
work, motivation to excel, adherence to high standards of
quality, selflessness in service to the university and the
profession, boundless energy and capacity for work-
that make him a valuable member of our faculty and of
our profession.
Massimo Morbidelli finds it hard to pick just one out-
standing attribute from the many things that he has learned
from Arvind. "The one that I am not sure I have learned, but
one that I certainly admire, is his honesty in science. By this
I mean not only of a moral but also of an intellectual nature.
In particular, stating and writing a concept only after he has
tried by all means to clarify and to penetrate it. I do not recall
a single time when he said, 'Well, it doesn't matter....' He
always wanted to go as deep as possible in all aspects of a
problem and in all details, which was not always easy for
grad students. Another aspect was his profound knowledge
of the literature and his capability of always giving appropri-
Winter 1998


ate credit to all other researchers."
"Above everything else, Professor Varma is an outstand-
ing individual who treats his students with courtesy and
fairness," Subramaniam adds. "Among the many memories
that I cherish from my graduate students days at Notre Dame
are the cookouts and get-togethers at his house. Professor
Varma and his wife, Karen, are extremely gracious hosts and
treated students to a variety of culinary dishes, including, of
course, spicy Indian food! The friendships and associations
forged there have been long-lasting. At the AIChE annual
meetings, Professor Varma makes it a point to organize a
dinner-outing with his former students. These outings have
become a pleasant forum for developing new friendships as
well as reminiscing about old times."
Arvind's commitment to his students extends beyond just
the schooling years. He has truly lived his belief of being a
model for them all.
In spite of the intense agenda of work and professional
activities to which he holds himself, Arvind has managed to
balance his time and interests between professional and fam-
ily obligations. He is quick to express pride in the accom-
plishments of Karen and his daughters, and he considers his
family to be the most important element in his life. Anita is a
1996 Notre Dame graduate in political science. She worked
for one year as a volunteer in the Americorps Vista project
and is currently a first-year law student in Washington, DC.
Earlier this year, she married Ken Motolenich, a Notre Dame
chemical engineering graduate with a master's degree in
environmental engineering from MIT. Their wedding in-
cluded both church and traditional Hindu ceremonies.
Sophia is currently a senior in high school, busy with
college applications, and has strong interests in drama
and musical theatre. Anticipating more free time in the
future, Karen has been preparing for the last several
years for a teacher's certificate in high school science
and expects to start her teaching career next fall. She is
also an accomplished opera singer. O










r department


Wayne State University


he Detroit metropolitan area is
one of the largest in the United
States. Businesses of every size
and kind, including the research and
production facilities-and world head-
quarters-for the "Big Three" U.S. au-
tomobile companies and many of the
high-tech companies that supply them,
are within a short drive of one another.
The excitement of these business and
research opportunities, combined with
the natural attractions of the Great Lake
State, bring nonstop traffic to the nearby
airport as people from around the na-
tion and around the world stream into
southeastern Michigan.
Amid this flurry of activity is Wayne
State University and its Department of
Chemical Engineering and Materials
Science. The department, chaired by
Esin Gulari, has 200 undergraduate stu-
dents, 120 graduate students, and 15
full-time faculty members. Students make full use o
research and employment possibilities presented by a
metropolitan setting and the facilities offered at a n
urban research university-all while learning in ,
and intimate departmental classes more reminiscent
private institution.
THE UNIVERSITY
AND THE METROPOLITAN DETROIT AREA
Wayne State University has the advantage of being i
middle of it all, literally and figuratively. Its location i
heart of metropolitan Detroit gives both faculty mer
and students the chance to explore great variety in the a
cultural and business communities. Metropolitan Detro
a worldwide reputation as a dominant manufacturing
and it is also gaining recognition as a center for techno
cal innovation. Through various co-op programs an
search collaborations between hundreds of these comp
and Wayne State, students have the freedom to incorp
on-the-job training into their overall education.


Wayne State's College of Engineering Building.


Most of Wayne State's 31,000 students commute to WSU
from the city and its suburbs, but thousands also come from
other states and countries. The campus has a richly diverse
faculty and student body, bringing different and unique per-
spectives to the classroom.
In addition, the metropolitan Detroit area has all of the
cultural attractions expected in an urban environment (most
within easy walking distance of the WSU campus) along
with the benefits of various recreational areas, many situated
on one of the state's 11,000 lakes. Sports are also prominent
in Michigan. Detroit's professional hockey, football, base-
ball, and basketball teams draw some of the nation's most
enthusiastic audiences.
Beyond its prime location, Wayne State University has
earned a reputation for its excellent educational, research,
and community-service programs. For example, Wayne State
is ranked as a Carnegie I Research University, placing it
among the top 88 universities nationwide to hold the presti-
gious designation. Conferred by the Carnegie Foundation


Copyright ChE Division ofASEE 1998
Chemical Engineering Education




























Chemical Engineering Faculty Members: Left to right, Professors Putatunda,
Matthew, Kummler, Ng, Salley, Gulari, Kannan, Rothe, Mao, Shreve, Huang,
McMicking, and Manke.

for the Advancement of Teaching, this title is reserved for universities that meet
highly selective criteria for emphasizing research in addition to undergraduate and
graduate education.
Wayne State University is in the middle of it all, and the Department of Chemical
Engineering and Materials Science has taken its place as one of the university's
premier departments.
THE DEPARTMENT
Students and faculty members alike find the Wayne State University Department of
Chemical Engineering and Materials Science to be an ideal size-small enough to
engender a sense of community, yet large enough to provide varied curricular and
research opportunities.
The sense of community is most clearly evident among the faculty members, who often
meet in groups to take casual lunches together, or who spend time in one another's offices
discussing progress in the lab or in the classroom. This atmosphere has also given rise to a
number of stimulating research collaborations among faculty members.
The department itself is a collaboration of sorts. In 1993, chemical engineering and
materials science, two separate but complementary disciplines, extended the good reper-
toire they had already developed and merged. Opportunities arose for cross-listed courses
and multidisciplinary laboratories.
For students, the dual-disciplined department also opens doors for them to have two or
more faculty mentors. In addition, students can learn from classmates and faculty mem-
bers in the other discipline and begin to see their field through others' eyes. Departmental
graduates find this kind of insight particularly useful in the workplace.
The curriculum in the department is wide in scope. The undergraduate program includes
courses that promote an understanding of physical, biological, and chemical operations
and processes. Graduate students can choose from a breadth of electives toward the MS
and PhD in chemical engineering, the MS and PhD in materials science and engineering,
Winter 1998


The department

... has 200

undergraduate

students,

120 graduate

students, and

15 full-time

faculty members.

Students make

full use of the

research and

employment

possibilities

presented by a

large metropolitan

setting and the

facilities offered

at a major
urban

research

university-
all while

learning in

small and intimate

departmental
classes

more

reminiscent of a

private institution.










and the MS in hazardous waste management. Specialized
training is also available, including graduate certificates
in polymer engineering, environmental auditing, and haz-
ardous waste control.
Outside of the classroom, students make use of modern
laboratory facilities throughout the Engineering Building,
computer workstations in the
Engineering Building and
around the campus, and a
complete university research
library. The newly opened un-
dergraduate library provides
ample study areas and ex-
tensive computer equipment
for student use.

THE UNDERGRADUATE
PROGRAM
Going well against the
grain, WSU's Department of
Chemical Engineering and
Materials Science brings to-
Professor Esin Gulari
gether the lower tuition rates Vi r Khn eri
of a public university, the
well-equipped laboratories of
a major research institution, and the small undergraduate
class sizes of a private college. This combination presents an
excellent environment for its students.
Class sizes are generally in the range of 20 to 25 students.
In this more intimate setting, students feel comfortable meet-
ing one-on-one with their professors and getting to know
their classmates. Students commonly create informal groups
to work out complex study problems or to prepare for tests,
both very effective learning tools.
Research is also a meaningful aspect of the undergraduate
educational experience within the department. Undergradu-
ate students can elect courses that involve research programs
or can take part in one of the many active projects of the
faculty members by accepting student research assistant-
ships. Either way, participating students can augment their
course work (and their resumes) both by working closely
with professors who are conducting related research and by
sharing a laboratory with highly trained graduate students
and with other like-minded undergraduate students.
While not a requirement, at least half of the undergraduate
students take part in the department's well-developed Coop-
erative Education Program. The unique relationship between
WSU and local industry helps to create the diverse opportu-
nities presented through the program. Participating students
alternate full-time study terms with full-time work assign-
ments in nearby companies. The location of the university
makes it easy for the students to commute from the work-
place to campus, and the department's accommodating course
10


and
g a


schedule has day and evening courses to meet the needs of
students in the program.
Another unique educational venture in the department is
the undergraduate seminar series that brings in scientists
from industry and academic institutions along with now-
working alumni. During each of the three semesters of semi-
nars the undergraduate students
are required to attend, each stu-
dent prepares a memo for the
department chair about his or
her educational progress and
thoughts about the overall de-
partmental program. The exer-
cise not only allows the stu-
dents to evaluate their goals,
but it also helps the chair to
prepare for the department's
future.

THE GRADUATE
PROGRAM

Research tAssistant The graduate program at
t polymer phases. Wayne State's Department of
Chemical Engineering and Ma-
terials Science is actually two
programs: one designed for doctoral students pursuing full-
time thesis research and another for master's students pursu-
ing part-time course work.
The opportunity for graduate thesis research is abundant.
Students, who come to Wayne State from the United States
and all over the world, choose a research advisor from an
internationally recognized faculty of active scholars. Re-
search topics available are particularly diverse and span
many of the "hot" new areas of chemical engineering, in-
cluding supercritical processing, interfacial phenomena, ad-
vanced materials processing, and bioengineering.
Strong federal, industrial, and internal support has resulted
in the graduate facilities at Wayne State being second to
none. For example, the department possesses several state-
of-the-art instruments, including atomic force microscopes,
an integrated optical biosensor, a rheo-optical FTIR spec-
trometer, various shear and extensional flow rheometers,
and an excimer-laser-based imaging system. Additionally,
connections with other research institutes on campus and
with local industries provide access to unique chemical and
material characterization facilities. Competitive stipends typi-
cally support the students.
Another unique feature of the Wayne State graduate pro-
gram is the course-work master's degree program. Students,
who typically are working engineers from the local area, are
able to complete their degrees in a reasonable time due to
flexible course offerings and the university's convenient
location. The department designs many of the courses in
Chemical Engineering Education










collaboration with industry to ensure that the students are
best trained to deal with the contemporary issues of the
discipline. As evidence of the program's success, Wayne
State is currently the nation's number-one conveyor of
master's degrees in chemical engineering.

GRADUATE CERTIFICATE PROGRAMS
Three graduate certificate programs round out the
department's curriculum: polymer engineering, environmen-
tal auditing, and hazardous waste control.
The Graduate Certificate Program in Polymer Engineering
provides specialized education for working engineers and
scientists. The program includes core courses and electives
(such as composite materials, polymer theology, and poly-
A mer kinetics) that are developed with input from profes-
The signals in industry. Students can complete the program in
Under- as little as one year.
graduate Designed with working professionals in mind, the Hazard-
Library ous Waste Control and Environmental Auditing programs
on have a combination of core courses and more specialized
campus. electives. The Graduate Certificate Program in Hazardous
Waste Control teaches state-of-the-art methods for he man-
agement, control, and disposal of a broad range of hazardous
substances, wastes, and materials. Students also gain practi-
cal knowledge in meeting government guidelines for waste
A management. The Graduate Certificate Program in Environ-
Salley Yurgelivic and mental Auditing covers the management, assessment, and
Suzanne Dakin, Research auditing of facilities and property, hazard identification,
Assistants. exposure, analysis and risk characterization, regulatory
noncompliance analysis, sources of liability, and alterna-
tives for corrective action.

RESEARCH
Professor Paul Van Research conducted in the WSU Department of Chemical
Tassel with Research Engineering and Materials Science falls into three expansive
areas; materials processing and synthesis; pollution preven-
tion and control; and bioengineering. Many of the
department's faculty members have interests that combine
more than one area (see Table 1, next page).
Dr. Joseph Smolinski The research of Esin Gulari and Charles Manke recently
and Research Assistant gained public attention when they received the highly re-
Zeynep Ergungor garded Henry Ford Technology Award. They became the
first non-Ford Motor Company employees to earn that
distinction. The award recognized their work in reducing
misting of metal-working fluids in Ford's manufacturing
plants. The two professors worked closely with all three
of the U.S. automotive companies, even using company
research laboratories and manufacturing plants to refine
and verify their results.
Both Howard Matthew and Guang-Zhao Mao hold Na-
tional Science Foundation Faculty Early Career Develop-
ment Program (CAREER) Awards. This prestigious award
recognizes faculty members who embody the excitement of
Winter 1998 11


I











TABLE 1
Faculty: WSU's Department of
Chemical Engineering and Materials Science
(Additional information through the CHE and MSE option on
the web page at http://www.eng.wayne.edu)

John Benci (PhD, University of Pennsylvania, 1989)
Deformation and fracture of materials
High-temperature mechanical properties of alloys, intermetallic
compounds, and ceramics
Esin Gulari (PhD, California Institute of Technology, 1973)
Thermodynamics and transport properties of polymer solutions and
melts
Processing of polymers with supercritical fluids
Light-scattering-based particle and drop-sizing techniques
Yinlun Huang (PhD, Kansas State Universtiy, 1992)
Pollution prevention and waste minimization
Process design and synthesis
Rangaramanujam Kannan (PhD, California Institute of Technology, 1994)
*Dynamics of polymeric systems and interfaces
Rheo-optical spectroscopy and scattering techniques
Ralph Kummler (PhD, Johns Hopkins University (1966)
Modeling of combined sewer overflows and sediments
Chemical kinetics
Computer simulations
Charles Manke (PhD, University of California-Berkeley, 1983)
Polymer processing and rheology
Molecular dynamics and kinetic theory of polymeric liquids
Guang-Zhao Mao (PhD, University of Minnesota, 1994)
Opto-electronic properties of thin films and crystals
Self-assembly of polymers and surfactants
Colloidal stability of waterborne paints
Real-time imaging of surface phenomena at the molecular level
Howard Matthew (PhD, Wayne State University, 1992)
Tissue engineering and biomaterials
Artificial organ substitutes
James McMicking (PhD, Ohio State University, 1961)
Correlation of thermodynamic data
Simon Ng (PhD, University of Michigan, 1985)
Heterogeneous catalysis
Polymer kinetics
Spectroscopic and thermal analysis of material surfaces
Susil Putatunda (PhD, Indian Institute of Technology, Bombay, 1983)
Effects of microstructure on fatigue
Fracture toughness
Creep in metals and alloys
Erhard Rothe (PhD, University of Michigan, 1959)
Applications of high-powered UV lasers
Machining of electronic chips
Diagnostics of internal combustion
Steven Salley (PhD, Detroit University, 1976)
Biochemical/medical engineering
Design of artificial organs
Immobilized enzyme reactors
Gina Shreve (PhD, University of Michigan 1991)
Environmental and biochemical applications
Microbially mediated biotransformations
Paul Van Tassel (PhD, University of Minnesota, 1993)
Shape-selective catalysis
Protein adsorption and bioseparations


research and learning.

Matthew's research involves tissue engineering and
biomaterials and is working toward developing tissue- and
organ-replacement systems. In one of his projects, he is
investigating the use of polymer composites to fabricate
small-diameter vascular grafts. The results are promising.
Mao is working on surface templates made of molecules
of mixed functional groups, She uses these molecular
templates to induce and control the growth of dye crystals
with tunable colors.

Among other things, Susil Putatunda is a cast iron
expert. His research centers on several areas, including the
development of high-carbon/high-silicon austempered steel,
the fatigue and fracture behavior of austempered ductile
cast iron, and the development of a fatigue-damage model
for polymer-based composites.

Another of the department's many active research groups,
led by Yinlun Huang, is studying intelligent process sys-
tems engineering and is developing a process synthesis
methodology based on artificial intelligence and fuzzy
logic. This work may lead to cost-effective, highly con-
trollable and environmentally benign process systems. In
addition, the research group hopes to meld optimal pro-
duction with pollution prevention in electroplating plants.

With its staff of full-time faculty members, the depart-
ment encompasses a diversity of research interests. While
the faculty members take cues from local industry, they
are very often much more than industry problem solvers;
they are research innovators. They develop the new tech-
nologies that entice industry to come to them.

THE FACULTY

Faculty members new to WSU's Department of Chemi-
cal Engineering and Materials Science are welcomed with
substantial start-up funding and institutional support.
They also find a firm advocate in the departmental
chair. Once on board, faculty members continue to
receive substantial internal support, including summer
and graduate student support.

The department's faculty team comprises fifteen full-
time members, each of whom holds a national reputation
in his or her specialty, and four adjunct professors who are
affiliated with the graduate program. The faculty members
have received many awards from prestigious engineering
organizations and other institutions in the profession.

The faculty of the Wayne State Department of Chemical
Engineering and Materials Science has many research
options and educational possibilities open to them and
their students. Being part of a major research university
located in the heart of a metropolitan area, they are able to
explore them all. O

Chemical Engineering Education











letter to the editor


Dear Editor:
In their recent article titled "An Experiment to Characterize a
Consolidating Packed Bed" (CEE, 31(3), p. 192, 1997), Gerrard,
Hackborn, and Glass misinterpret the Kozeny equation for low gas
flow through packed beds and consequently arrive at an incorrect
result.
The Kozeny equation as written by these authors is
Ap= 5a2(1- e)2 hv /3 (1)
(Nomenclature and numbering of equations follow those of the
article criticized, with the addition that numbers assigned to cor-
rected equations have the letter "a" appended to them.) In this form
of the equation, the term a signifies the specific surface of the
particles in the packed bed, i.e., particle surface area/particle vol-
ume, and is independent of the bed consolidation (assuming rigid
particles). Therefore, in the authors' terminology,
a = ao (3a)
The specific surface of the packed bed, particle surface area/bed
volume, is given by the product a(l E). Unfortunately, the authors
incorrectly assume that a alone signifies the specific surface of the
bed, and hence they write
a =aoho /h (3)
which is incorrect for a as used in Eq. (1).
If instead of Eq. (3), one correctly substitutes Eq. (3a) and the
authors' Eq. (2),
(1- )h (2)


into Eq. (1), the result is
5 a2h(l- e)2lvh2
Ap h-(l-ojh43
{h-(1-o)ho}3


where


Ap = kvh2 /(h- G)3


k= 5aoho(1- )2is


G=(l-eo)ho (7)
Rearranging Eq. (5a) gives

(hv/Ap) = k h-k G (8a)
Thus it is (h2 /Ap) and not (v/Ap) 3, that should be plotted
against h in order to linearize Eq. (5a). That approximate
linearlization was actually obtained by plotting (v/ Ap) /3 instead
of (h2/Ap)1 against h can be attributed to the fact that the
maximum decrease in h2/3 for the experiments performed was
only 1-(0.41/0.61)2/3 = 23%.
The authors should note that if they were to substitute their Eq.
(9),
a = 6(1- )/Dp (9)
into Eq. (1), the right-hand side of the latter equation would then
contain (1- e)4 in the numerator, which is clearly incorrect. The
error arises from the misinterpretation of a, which is not the packed
Winter 1998


bed specific surface given by Eq. (9), but the particle specific
surface given by
a = EnD/(nt/6)D3 = 6/Dp (9a)
(Alternately, if we define a as the authors have done, then the
(1- E)2 term in Eq. (1) would disappear.)
Professor Norman Epstein
Department of Chemical Engineering
The University of British Columbia

Dear Professor Epstein:
Thank you for pointing out the correction, which makes the fit
even better.
Professor Mark Gerrard


Book review


Batch Distillation
Simulation, Optimal Design and Control
by Urmila M. Diwekar
Published by Taylor & Francis, 1101 Vermont Ave., N.W., Suite 200,
Washington, DC 20005; 211 pages including index; $59.95 (1995)

Reviewed by
Phillip C. Wankat
Purdue University

Batch processes, and batch distillation in particular, are
understudied in universities. The typical undergraduate sepa-
rations textbook devotes a short chapter to batch distilla-
tion, and typical coverage in courses (CEER, 28, p 15,
1994) is from one to three class periods. The average gradu-
ate student does no additional study of batch distillation.
Yet, batch distillation is an increasingly important separa-
tion method in industry, and there is significant interest in
batch distillation research.
Batch Distillation, which is "primarily designed to serve
as a textbook for a graduate course," is very timely. The
companion software MultiBatchDS (education edition from
CACHE Corp.) was not available and is not reviewed here.
A review of the book and the software from a consultant's
viewpoint was recently published (Chem. Engr. Progr., p.
77, June 1997).
If the software is available, this would be a good text for a
graduate-level course. There are 38 homework problems in
the book, which is probably sufficient for the first time the
course is offered. With the exception that packed columns
are not covered, the coverage is broad and most topics of
interest are included.
Chapters 1 and 2 introduce batch distillation and analyze
binary systems. These two chapters are a good resource for
professors and undergraduate students, but some professo-
rial guidance will be needed. For example. Eq. (1.6) and
Continued on page 81.
13










p -- curriculum


CHEMICAL ENGINEERING

AND THE OTHER HUMANITIES*



J.M. PRAUSNITZ
University of California Berkeley, CA 94720


How is engineering related to other intellectual or
professional disciplines? What is the role of chemi-
cal engineering in a modern university, and how
does it fit into the spectrum of knowledge? And, finally,
what can possible answers to these questions tell us concern-
ing our educational philosophy and curriculum for training
the engineers of the future?
These are difficult multidimensional questions with many
aspects. I will discuss here only one aspect, one that is
essential but has not received much attention: the need to
remember that chemical engineering is not an isolated sub-
ject; that it is not limited to applied science, but rather is a
significant part of daily life, related to health, to human
relationships, to politics and sociology and law, to the way
we think and feel about ourselves as individuals and as
members of society, to our aspirations, our hopes, and our
fears. In other words, I want to emphasize the old but too-
often forgotten concept that chemical engineering is not
apart from, but indeed a part of, what (broadly speaking)
we call the humanities.
Toward introducing that concept, Figure 1 shows a fa-

John M. Prausnitz, Professor of Chemical Engi-
neering at the University of California, Berkeley,
has devoted most of his professional career to
phase equilibria as required for process design.
His undergraduate education was at Cornell Uni-
versity, and he received his PhD from Princeton,
which also gave him an honorary Doctor of Sci-
ence degree two years ago. Author or coauthor
of more than 500 technical publications, he is the
senior author of the widely used text Molecular
Thermodynamics of Fluid-Phase Equilibria.

* Adapted and abbreviated from a lecture delivered at Notre
Dame University, The University of Missouri-Columbia, and the
University of Michigan (1996-97).


mous painting by Titian. The painting, about 400 years old, is
in the Borghese Palace in Rome and is titled Sacred and
Profane Love. Early in this century, a copy of the painting
was on the wall of the seminar room of the Institute for
Mathematics at the University of G6ttingen in Germany.
From the middle of the nineteenth century until 1933, when
the Nazis started to destroy the German universities, Gottingen
was the world's leading center of mathematics, attracting the
best minds of the day. In the seminar room, underneath the
painting, was not the original title but a new one, Pure and
Applied Mathematics.
We do not know who retitled Titian's painting, but it was
not only for amusement. The institute at Gittingen was far
ahead of its time; not only was the mathematics done there
new, vigorous, and bold, but (what was, and too often is still,
unusual) the Institute also did outstanding work in both pure
and applied mathematics. It was far ahead of other mathemat-
ics departments and gave serious attention to numerical meth-
ods for solving difficult differential and integral equations.
The painting and its new title were intended to stimulate
discussion, starting with the obvious question: there are two
female figures-which one represents pure mathematics and
which one represents applied mathematics? The question can
be argued either way. The woman without clothes could be
identified with carnality, with the physical as opposed to the
spiritual side of life, and therefore represents applied science,
while the clothed, serious, brooding woman represents as-
cetic values, divorced from earthly concerns, and thereby
represents pure science. On the other hand, we could argue
that the absence of clothing and the upward ecstatic glance
toward heaven represents purity, while clothing (notice that
the clothes are coarse and drab) represents earthly values and
that the clothed woman's dour, downcast look represents the


Copyright ChE Division ofASEE 1998


Chemical Engineering Education











... chemical engineering is not an isolated subject;.. .it is not limited to applied science, but rather
is a significant part of daily life, related to health, to human relationships, to politics and
sociology and law, to the way we think and feel about ourselves as individuals
and as members of society, to our aspirations, our hopes, and our fears.


applied sciences that
must deal with daily
realities.
Titian's painting
shows that there is a
unity in opposites, an
old idea in philoso-
phy: truth and ultimate
reality are revealed to
us in a variety of
faces. In today's
world, we talk about
unity in diversity, we
read books about the Figure 1. Sacred and Profane Lc
Sciences Institute of the Univ
increasingly similar Pure and Appl
roles of male and fe-
male, and we profess
the virtues of blending Eastern and Western cultures. Sacred
and Profane Love (or Pure and Applied Mathematics) illus-
trates the fuzziness, the growing disappearance of borders
between intellectual categories. It shows what is increas-
ingly recognized in universities today-that, while uni-
versity departments may be necessary for efficient ad-
ministration, intellectual concerns now overflow depart-
mental division. Intellectual concepts are increasingly
delocalized as the interests of faculty in one department
overlap those in another.
My claim, that chemical engineering is one of the humani-
ties, goes beyond the by-now clear evidence that contempo-
rary chemical engineering is increasingly related to a variety
of other physical and biological sciences. What is only slowly
becoming apparent is that chemical engineering is also closely
related to the social and humanistic "sciences," where "sci-
ences" is now in the original sense of "scientia"-that is, not
necessarily natural science, but more generally, knowledge
in all of its varieties. This close relationship follows from
both practical and intellectual trends in contemporary soci-
ety, as I shall now try to explain.
The practical trend is so fundamental that we are tempted
to forget it: chemical engineers exist because society wants
chemical products that will satisfy human needs. Chemical
engineering is driven by society's wish for a better life,
where better is not only materialistic, but also deeply hu-
man-as for example, in medicine and pharmacy for health,
in cosmetics for beauty, and in agricultural chemicals for
feeding a hungry world.


wve,
ersit
ied


I can best illustrate
the practical and also
deeply human basis
of chemical engi-
neering by recalling
a revealing anecdote
from a late col-
league, Professor
Irving Fatt, in
Berkeley's optom-
etry department. He
asked his class,
"Who is respon-
by Titian. In the Mathematical sible for the multi-
y of GBttingen it was retitled million dollar con-
Mathematics. tact lens industry?"
As usual, initially
there was silence, followed by some students shyly men-
tioning names of prominent polymer scientists. "Wrong,"
replied Fatt, "The father-more correctly, the mother-
of the contact lens industry was a poet, Dorothy Parker,
author of the immortal lines, 'Men seldom make
passes...At girls who wear glasses."'
Chemical engineers are driven into ever-new areas by the
needs, often deeply humane needs, of a society that wants to
improve its quality of life. Chemical engineers work not
only to make girls more attractive, but also, for example, to
make acid-free paper for preserving literary and historic
documents, to make new drug-delivery systems for chronic
illnesses such as diabetes, to make special paints and glues
for restoring old paintings and archeological artifacts, to
make new wound dressings for severe burns, to make
water-absorbing gels for diapers and for providing mois-
ture to the roots of desert trees that yield not only fruit
for food, but also shade from the brutal sun. If the goal of
chemical engineers is to satisfy human needs, chemical
engineers must have some understanding of human na-
ture, of psychology and international relations, of social
organizations, and of the clash of cultures.
Chemical engineers do not live or work in a vacuum. They
must understand labor laws, health insurance, safety, pollu-
tion abatement, and local customs and cultural values-in
other words, the concerns of social scientists from econom-
ics to sociology. But beyond that, a successful chemical
engineer must also understand how his product can either
satisfy or offend his constituency; he must have some un-


Winter 1998










derstanding of the ever-so-complex human
soul, and that inevitably leads him to his-
tory, to psychology and to art-in short, to
the humanities.
Both practical and intellectual trends in con-
temporary society make chemical engineer-
ing one of the humanities. The intellectual
trend is not as evident as is the practical one,
but it is clear to anyone who is familiar with
what literature, art, and philosophy have em-
phasized for at least two generations: the dis-
solution of boundaries, the inter-relatedness
of objects, phenomena, and observers. Noth-
ing stands alone. Any one thing is without
end, related to many other things. Literary
critics tell us that to understand a text, we
must probe not only into the author's history
and his state of mind when he wrote his text,
not only must we consider the customs and
prevailing values that existed when the text
was written, but we must also probe into the
reader's history and his values and his state
of mind when he reads the text. Thus, every
interpretation depends on numerous factors,
including the color of the book cover and the
type of paper used by the printer. In the limit,
this critique leads to the infamous movement
"Deconstruction" where ultimately nothing
objective remains. The only remaining ulti-
mate reality is inter-relations.
The dissolution of boundaries is strikingly
evident in art. Figure 2 shows Escher's Night
and Day. Notice how the white birds flying
to the right change, not abruptly but continu-
ously, to black birds flying to the left.
The dissolution of boundaries extends not
only in space, but also in time. Figure 3 shows
a famous painting by Marcel Duchamp titled
Nude DescendingStairs (An unsympathetic
critic called this painting "Explosion in a Tile
Factory.") We cannot localize the young
woman; her fuzziness is not only spatial, but
also temporal; she is simultaneously at the
top of the stairs and at the bottom.
A related idea is indicated in a remarkably
simple modern sculpture by my former gradu-
ate student, Dr. Bryan Rogers, who is now
chair of the Art Department at Carnegie
Mellon University. Bryan is probably the only
person in the world who has a joint PhD in
chemical engineering and in art. Figure 4
shows a set of clocks as found in any interna-
tional airport. But the usual designations, e.g.,


Figure 2.
Night and Day,
by Escher


Figure 3.
Nude
Descending Slairs,
by Duchamp










Figure 4.
Berkeley,
by Rogers


BERKELEY BERKELEY BERKELEY BERKELEY




BERKELEY BERKELEY BERKELEY BERKELEY



Chemical Engineering Education










New York, London, Tokyo, Moscow,
etc., have all been replaced by Berke-
ley. We see here the idea of inter-relat- [We ml
edness. No place is isolated; what hap- studei
pens anywhere in the world, happens technology
also in Berkeley. human n
Twenthieth-century philosophers like person
Heidegger, and especially his German dis- cole
ciple Georg Gadamer, and to some extent how appli
his American admirer Richard Rorty, have a response
emphasized the importance of context and aspiration
contingency. The significance and effec- often is
tiveness of any object lies not in itself, but conseque
in how it interacts with its environment, also a st
This fundamental idea has greatly influ- re
pure s
enced recent and current work in history, and how t
literature, economics-in just about every
social science and humanities department
women wa
in every major university. women w
drive the
In literature, history, anthropology, so- ro
ciology, law, business administration, etc., depart
emphasis is increasingly placed on inter-
cam
relationships, on how one subject is re-
lated to another-in other words, on con- Like every
text. Historians of art are not only looking scholarly
at what artists were doing at the time when engine
a particular painting was created; they are philologist,
also looking at the social relations that economists
artists had with each other and their pa- or theol
trons, at the political climate of the time, strive tow
at the literature of the day, at religious underst
practices and conventions, and at the ourselves c
mechanisms artists used to publicize and more n
market their work. Researchers in busi-
ness administration are no longer prima-
rily concerned with the internals of a cor-
poration, but instead, with how the corporation relates to the
community, with health and safety matters, with how corpo-
rations interact with other corporations, with government,
and with social groups representing a variety of religions
and ethnic traditions. Mathematical economists are inter-
ested not only in cash flow, taxes, and interest rates, but also
in so-called externalities, including psychological factors,
tastes, fads, fashions, perceptions, and the persistence and
decay of myths and folklore.
No objects or subjects exist by themselves, but always in
relation to other objects or subjects. Chemical engineering,
by itself, has no value. The value and legitimacy of chemical
engineering arise only when it stands in relation to some-
thing else, toward satisfying some human need, toward
answering a question of deep human concern. Chemical
engineering is an applied science in detail, but it is a
humanity in intent.
Winter 1998


rst]
nts I
is r
eed
nal
ctiv
ed s
e to
s an
not
nce
imu
cie
he c
mel
nt c
Sac(
msf
men
npu,
one
insl
!eer
s, ch
s, p1
)gia
ard
and
mnd
obl


For chemical engineering education, the
essential role of context should not be del-
show egated to courses in humanities. To be truly
low effective, they can easily be integrated into
elated to the present chemical engineering curricu-
s, both lum. It takes only a little time to show stu-
and dents how chemical sciences relate to the
re; world around us. Toward that end, the main
science is requirement is an open-minded attitude by
human instructors, a willingness to depart from that
d how it confined area where they are expert and feel
Totally secure and to devote a few minutes
just a
to related areas where they are not expert
uof but but where the relevance of their subject lies
lus to, and where they, as role models, can show
nce; humanity and openness to the world rather
concerns than the confinement of a narrow spe-
n and cialty. All too often the image that fac-
md need ulty present is such that only the instruc-
idemic tors' expertise is visible, while their di-
or all verse talents, interests, passions, and
its on weaknesses-in short, their humanity-
remains hidden. No wonder that so many
else at a students think of faculty as a species sepa-
on rate from the rest of humankind!
titution,
sor The regrettable bifurcating mind of many
emists or faculty was aptly described in a short story
ysicians by the Italian writer Ignazio Silone. In this
story, the wife of a professor talks about
ns, we him and gives the concise description,
a better "Oh, he knows everything. But that's all
!ing of he knows."
toward a
to d a When we present the principles of refrig-
e life. eration, we usually take a few minutes to
discuss the desirable properties of refriger-
ants, including freons. At that time, it is a
simple matter to talk briefly about how some freons attack
the ozone layer that protects the earth from excessive ultra-
violet radiation and to indicate the need for synthesizing
new compounds that can serve as environmentally ac-
ceptable refrigerants.
To illustrate the principles of heat transfer, we need not
confine attention to the time-worn double-pipe heat ex-
changer. Along with the usual equations for conduction,
convection, and radiation, we could also talk about solar
energy, cooling requirements for supercomputers, heat ef-
fects in reentry of space vehicles, cryosurgery, and such
home-related topics as microwave ovens, fire-resistant paja-
mas for infants, or design of an effective fireplace.
When we talk about flowing fluids, let's mention check
valves, rupture discs, human failures, and the tragedies at
Bhopal in India and Chernobyl in the Ukraine. When we
discuss condensers, let's mention fog at airports. When
17









we derive colligative properties of solutions, let's talk about
salt for removing snow on our streets and then about
subsequent corrosion of automobiles. When we discuss
evaporation, let's mention desalting of sea water and the
drought in Ethiopia.
When we encounter the free en-
ergy of formation of ammonia, let's
also say something about fertiliz-
ers, about starvation in Somalia,
and perhaps a few words about the
latest farm bill passed by Congress.
Further, let's recall for our students
that ammonia is used for making
nitric acid, that nitrates are used
for making explosives, and that if
Fritz Haber had not invented his
synthetic-ammonia process early
in this century, Germany would
have run out of ammunition in
1915 and would have been un-
able to continue World War I af-
ter the first year.
I mention these examples not
only to stress the relevance of
chemical engineering, but also to
suggest that, when taught with gen-
erosity, chemical sciences can serve
as an integrating factor for under-
standing our living world as de-
scribed in newspapers, television,
and history books. Fig
To prepare students properly for I and My Vil
meeting the expanded expectations
of society, faculty can no longer restrict their undergraduate
courses to narrow specialization with the comfortable thought
that the student's "other" educational needs will be supplied
on the other side of the campus. The responsibility for good
education cannot be so easily compartmentalized. There is a
crucial difference between the words integrated and sepa-
rate but equal, as the U.S. Supreme Court decided about
forty-five years ago.
If we believe-and I suspect that we all do believe-that
engineering is ultimately not merely a technical but also,
essentially, a human enterprise, then we are obligated to
communicate that belief to our students in a consistent way.
We cannot meet that obligation by merely requiring our
students to attend an occasional course in history or anthro-
pology or whatever. If we are to be consistent in our
purpose, then it is our task, in our own courses, to show
the intimate continuity between applied science and ulti-
mate human concerns.
Pressures from government and its funding agencies are


'ure
lage


already providing incentives to encourage teamwork in re-
search, better cooperation with industry, team teaching, in-
terdisciplinary courses, and lowering of departmental barri-
ers-in short, toward integrating engineering education and
research with those broad areas that
engineering serves. Funding agen-
cies now prefer research proposals
that are problem-oriented, to be
conducted not by separate investi-
gators but by a team of scholars
from several disciplines. At the
same time, students and parents are
demanding that more attention be
given to courses that emphasize
"why" instead of "how," that
stress overall purpose rather than
details of method, and, as a per-
ceptive undergraduate at the Uni-
versity fo Rochester said, "to
courses that give fewer scales and
more music."
As it prepares for the next cen-
tury, every chemical engineering
department faces two challenges.
The first one is well known and
relatively simple: to keep up with
impressive new developments in
science and to make them relevant
for practice. Surely that is one of
the traditional goals of engineer-
Sing. It is likely that essentially
all chemical engineering depart-
e, by Chagall ments will meet this first chal-
lenge with success.
The second, and more difficult, challenge is to humanize
the curriculum, not through new courses but by introducing
into existing technical courses the human dimension; to show
students how technology is related to human needs, both
personal and collective; how applied science is a response to
human aspirations and how it often is not just a consequence
of, but also a stimulus to, pure science; and how the concerns
of what men and women want and need drive the academic
programs for all departments on campus. Like everyone
else at a scholarly institution, engineers or philologists,
chemists or economists, physicians or theologians, we strive
toward a better understanding of ourselves and toward a
more noble life. In our relations with students and faculty in
other departments, let us not be separated by our differences
but joined by our common purpose.
I plead for teaching this commonality of purpose not only
because it is fashionable to reverse the alarming trend of the
university to a multiversity. My plea is motivated by two
equally important goals.

Chemical Engineering Education










First, if we humanize our cur-
riculum, we produce better engi-
neers, we raise the prestige of en-
gineering, and we help to combat
the threatening anti-science and
anti-technology movements that
are growing in our alienated popu-
lation. Engineers must increas-
ingly communicate, to listen with
empathy to those who do not un-
derstand or who are frightened
by new technology, and to speak
to them effectively, leading them
toward confidence and trust.
Good skills in English are not
enough. The engineer must also
have some understanding of his
audience; in other words, he
needs to understand the human
dimensions of his work. In the
world now emerging, an Ameri-
can engineer must know how to


n+l

t I n


n-1



MATERIAL BALANCE


Ln.1 + V.-, = L. + Vn



V = VAPOR FLOW RATE t
L = LIQUID FLOW RATE ,

Figure 6. Free-body diagram for plate n in a
distillation column.


communicate, to listen and to
speak, with a peasant in India, a rabbi in Jerusalem, or a
lawyer in Washington.
Second, a chemical engineering department is not a trade
school. A worthy chemical engineering department is not
content to limit its educational efforts toward producing
robots for industrial employment; it strives to produce
thoughtful, sensitive, and independent-minded graduates
who are not only competent engineers but also well-
educated individuals, prepared for fulfilling lives both
inside and outside their profession. To achieve this edu-
cational goal, engineering faculties must integrate and
interrelate what we do in engineering with the greater
world that engineering aims to serve.
Toward explaining my conviction that engineering is an
integral part of our spiritual as well as our physical exist-
ence, I have shown examples from several artists. Finally, I
would like to show one more: a well-known painting by
Marc Chagall, painted about seventy-five years ago when
Chagall was a young man remembering his childhood in
rural Russia. In a sense, it is an autobiography. It is called I
and My Village (Figure 5), and it indicates the influences
that made Chagall the particular individual that he was at
that time. It shows a set of memories that are separate, yet
integrated to form a harmonious continuum.
Contrast this painting with the essential image we use to
teach applied mechanics-the free-body diagram. In a free-
body diagram, we isolate the essentials of our focus of study,
we neglect the surroundings, and we ignore the context.
In teaching chemical engineering, we also use free-body
diagrams. For example, as shown in Figure 6, in teaching
Winter 1998


distillation we look at one plate in
the distillation column and then write
mass balances for all flows that en-
ter or leave that plate. In this exer-
cise we forget not only the rest of
the distillation column but also the
entire chemical plant and the com-
munity that it serves.
I am not opposed to free-body dia-
grams, nor do I suggest that we re-
frain from using them in instruction.
Free-body diagrams constitute a
pedagogical tool that has been, and
continues to be, valuable for effec-
tive education. But free-body dia-
grams convey an attitude, a philo-
sophical viewpoint that is seriously
incomplete. We should not abandon
free-body diagrams, but we should
not restrict engineering education to
the attitude that they imply. I plead
for a shift of balance where we rely
not only on the isolated specifics but


also, as suggested by Chagall's painting, give attention to
the larger view, toward awakening engineering students to
see both the leaves on the trees and the forest, the mountains
and the cities, and the human beings that live in them.
To illustrate this shift of balance, to help our students
broaden their professional horizons and to attain more mean-
ingful lives, it may be useful to recall a well-known (possi-
bly true) story concerning the great physicist Niels Bohr.
Bohr, a distinguished professor of physics at the Univer-
sity of Copenhagen, liked, on occasion, to retreat to a modest
cabin in a nearby forest where he could read and think
without interruption. But an enterprising journalist discov-
ered this cabin, and wanting to interview Bohr, knocked on
the door. Bohr opened the door and the journalist entered.
When he did so, he noticed an old horseshoe nailed to the
door frame. Surprised, he said to Bohr, "You are a great
scientist. Surely you are not superstitious. Surely you do not
believe that a horseshoe can bring good luck." Bohr an-
swered without hesitation, "Of course I do not believe that.
But I have been told that a horseshoe can bring good luck
even if you don't believe it."
This charming story tells us once again that, even for a
great scientist, life has a strong non-rational component and
that we are all human beings subject to the hopes and fears
that characterize the human condition. Let us reflect this
duality when we teach our students science and technology.
Let us not rely on others to do what we owe to the young
men and women entrusted to our care. Let us show by our
example and in our classrooms, that engineering, in particu-
lar chemical engineering, is also one of the humanities. O










" classroom


COMET

An Open-Ended, Hands-On Project

for ChE Sophomores

MARK R. PRAUSNITZ
Georgia Institute of Technology Atlanta, GA 30332-0100


"Georgia Tech was the site of intense competition Monday. but this time it was not Olympic
athletes who sought gold. Instead, eleven determined teams made up of chemical engineering
majors met in quadrant tr o of SAC's main gym to embark on a battle of wits.... Kamikaze
team member Heather Ledbetter explained howa her team's COMET operated: "Our COMET
stores elastic potential energy by displacing a spring. This potential energy is then converted
to work, acting on our projectile-an egg.... The peeled egg worked the best. "*


Sophomore chemical engineers at Georgia Tech re-
cently built Controlled-Operation Mechanical Energy
Transducers (COMETs) as part of a project to intro-
duce them to a number of important engineering concepts
that are often not addressed until later in the curriculum, if at
all. In the COMET competition, student teams designed,
built, and used simple, self-powered devices that indepen-
dently traveled to a designated location.
While electrical and mechanical engineering students fre-
quently participate in design competitions involving stu-
dent-built machines,11 chemical engineering students' hands-
on experience is usually limited to prefabricated laboratory
experiments during the junior or senior year. To introduce
activities other than pencil-and-paper homework assignments
earlier in the curriculum, development of hands-on design
projects appropriate for beginning chemical engineers has
recently received increased attention.[2'31 Motivated by this
concern, I developed and offered the COMET competition

Mark Prausnitz is Assistant Professor of Chemi-
cal Engineering at Georgia Tech. He was edu-
cated at Stanford University (BS, '88) and MIT
(PhD, '94). He currently teaches mass and en-
ergy balances to chemical engineering sopho-
mores, recently spent a year teaching biomedical
engineering in developing countries with ORBIS
International, and has taught public speaking for
more than ten years. He conducts research on
novel mechanisms for improved drug delivery by
controlling tissue permeability using electric fields,
ultrasound, and microfabricated devices.

* Excerpt from a final COMET report written by a team of


students.


-50'
-35' 5'
Figure 1. Schematic of the COMET competition arena
located on an indoor basketball court. COMETs traveled
by land and/or air from a launching area, around or over a
large barrier, and to as close to a target location as pos-
sible. The COMETs were designed and built by teams of
sophomore chemical engineers.

in two consecutive sophomore-level classes on energy bal-
ances.[4] It was designed to achieve the following goals:
Teamwork Students formed teams of two to four mem-
bers who worked together on all aspects of the projects.
Open-Ended Problem Because there were few rules in
the competition, many possible designs could accom-
plish the assignment.
Design Given only a spending limit and a final goal,
students had to design, build, test, and use their COMET.


Copyright ChE Division ofASEE 1998
Chemical Engineering Education










Hands-On Experimentation Because a successful
COMET design depended largely on empirical physical
testing, students needed to get their hands dirty.
Technical Writing Each group prepared a final report
that described and analyzed the design of their COMET,
including written text, figures, and calculations.
Estimation Based on Limited Data Quantitative esti-
mates of kinetic and potential energies were required in
the final report. Students designed and performed addi-
tional experiments to calculate rough estimates of those
energies.

THE ASSIGNMENT

The COMET project had few rules, thereby giving stu-
dents the opportunity for creative
design. In groups of two to four
students, each team designed and A
built a COMET that could be
launched from a designated lo-
cation and, without human inter-
vention after launching, would
come to a stop as close as pos-
sible to a target location approxi-
mately forty feet away (Figure
1). To make the assignment more
challenging, a large object was
placed five feet in front of the
target so that a straight path to
the target would be blocked. The C
COMET had to cost less than
$20, measure less than one foot
in all dimensions, have no elec-
trical, chemical, or human power
sources, and be safe. The
COMET could have a separate
launching unit of any size, but
the launching unit had to remain
behind the starting line.


The assignment was given to
the students two to three weeks
before the competition. Immedi-
ately before the assignment was
given, we held an in-class brain-
storming session to help students
think broadly about the project.
We identified possible paths an
object could follow between two
points separated by a barrier and
considered ways in which an ob-
ject could be powered to follow
some of those paths.
One week before the competi-
Winter 1998


tion, a preliminary design of the proposed COMET and its
expected course was collected to ensure that each group had
started work on the project. I provided feedback on these
preliminary designs, commenting on approaches that seemed
overly complex, unlikely to work, or unsafe. Students also
received sample energy balance calculations to guide them
in preparing their reports, as described below. Optional prac-
tice sessions were held before the competition so that teams
could test their COMETs in the competition arena.

THE COMET COMPETITION
The competition consisted of three rounds. During each
round, each team in turn launched its COMET toward the
target (see Figure 2). The referees (i.e., class TAs) measured
the shortest distance between the target and the COMET.


Figure 2. COMETs being
launched at the competition.
(A) The "Tomato" team shot a
rice-filled balloon from a rubber
band-powered cannon.
(B) The "Quadrangular" team
COMET drove to the side of
the barrier and then made a 90'
turn by triggering a second
set of wheels.
(C) The "Slingers" launched a
putty-based COMET from
a slingshot.
(D) The "Spartans" vehicle
followed an arced path around
the barrier and was powered
in part by a rat trap.










After the third round, the teams were ranked by aggregate
score from all rounds of play. Members of the winning team
each received a small trophy.


The ability of the COMETs to reach their
target ranged from reproducibly having no
net movement to reproducibly landing and
stopping within inches of the target. Most
designs were based on potential energy stored
in the form of a spring or rubber band that
was used to catapult an object through the air.
Others used the potential energy of gravity to
move the COMET either on the ground,
through the air, or a combination of both.
Designs ranged from store-purchased pro-
jectiles modified for the competition to home-
made vehicles, some with complex and clever
mechanisms to control the COMET's direc-
tion and speed. While the complex designs
were fun to see, they were generally unreli-
able and yielded only average performance.
The winning designs in both of the COMET
competitions were either a rocket or an arrow
launched from the ground at a predetermined
angle with a reproducibly applied force and
having a mechanism to prevent rolling or
bouncing once the COMET hit the ground.

THE FINAL REPORT
Although the competition was the highlight
of the COMET project, grades were deter-
mined from each team's final report. The re-
port was due two days after the competition
and consisted of four parts:


1. A schematic diagram and description of the
COMET
2. A sketch and description of the intended course
the COMET would follow
3. Receipts for items used to build the COMET
4. Quantitative energy-balance calculations for each
phase of the COMET's travel
Grading was based half on clear, concise, and neat presen-
tation and half on energy balance calculations. Quality of
COMET design and construction and the COMET's ability
to reach the target did not influence grades as long as each
team had made a reasonable effort to do well.
The final reports were generally clear and well written,
and they provided reasonable analysis of the energy bal-
ances associated with the COMET's travel. The sketches of
the COMET design and its intended course were mostly
simple, hand-drawn diagrams (see Figure 3) supported by
one or two paragraphs of descriptive text. The receipts all


totaled under $20, as required in the assignment; some
amounted to just a few dollars.


... Control
Operation Mec
Energy
Transduce
(COMET
... part of a pr
introduce
[sophomores
number of imf
engineering co
that are oftej
addressed unt
in the curricu
if at all. In
COMET compi
student tea
designed, build
used simp.
self-powered d
that indepenc
traveled to
designated loc


to share group responsibilities. They also approached this
open-ended design project with an open-minded attitude, as
demonstrated by the many different types of COMETs built,
most of which worked well. Students spent a lot of time
building and testing their COMETs, which indicated they
enjoyed the opportunity for hands-on learning. The final
reports contained adequate technical writing and data analy-
sis, topics that are addressed more thoroughly in later classes.
To assess student opinion of the project, a brief, anony-
mous survey[5'61 was given a week after the assignment. It
revealed that students generally found the COMET project
to be educational, enjoyable, and worth repeating. Figure 4
shows student responses to the three specific questions asked.
Students also provided written comments, which are sum-
marized below.
The average scores shown in Figure 4 indicate generally
favorable responses by the students, but not enthusiastic
endorsement of the project. This observation should be tem-
pered in two ways. First, a large standard deviation is associ-
ated with each average, largely due to a few students who
Chemical Engineering Education


Students performed energy balance calculations for each
phase of the COMET's travel. A representa-
tive example follows, taken from the "Ber-
led- noulli Bunch" group's analysis of a COMET
hanical that was shot into the air from a rubber-band
sling shot, landed on the ground, and finally
bounced and rolled to a stop. First, these stu-
ers dents estimated the elastic potential energy of
) the rubber band by shooting an object of known
oject to weight straight up into the air. They measured
e the maximum height of the object and, assum-
] to a ing no friction with the air, set the elastic
ortant potential energy lost by the rubber band equal
to the gravitational potential energy gained by
ncepts the object. They determined this energy to be
n not 1.4 J. They then calculated the COMET's ve-
il later locity to be 11 m/s upon leaving the rubber-
ilum, band launcher by setting the COMET's ki-
the netic energy equal to the potential energy lost
petition, by the rubber band. Using energy balances
applied when the COMET reached its maxi-
mns mum height, first hit the ground, and finally
t, and stopped, they determined at each point the
le, COMET's kinetic and potential energy, as well
devices as its position and velocity.
gently ASSESSMENT OF THE PROJECT
oa
From the instructor's perspective, the
COMET project accomplished the six goals
for which it was designed. Students responded
well to the teamwork environment and seemed













































Figure 3. A sample student sketch of the intended
course the COMET would follow to the target (above)
and a schematic diagram of the COMET launching
unit (below) from the "COMET Busters" team final
report.


1 2 3 4 5

learning


enjoyment


use again? ]


Figure 4. Student assessment of the COMET project.
Based on anonymous responses from 28 students (solid
bar) and 34 students (grey bar) in two different classes,
averages and standard deviations are shown for re-
sponses to the following: Rate your learning from the
COMET project (1 "waste of time" to 5 "very valu-
able"); Rate your enjoyment of the COMET project (1
"dull" to 5 "lots of fun"); Give your recommendation
on using the COMET project again (1 "absolutely not"
to 5 "absolutely yes"). Overall, students found the
COMET project to be educational, enjoyable, and worth
repeating (see text).
Winter 1998


covnt ouMTze
11-


comet


7 as
i. 25 ft


4*,,


- 1- -.n 1.. -


were unhappy with the project and rated it with a 1 or 2. The
vast majority of students gave ratings of 3 and higher on all
three questions. If the averages were recalculated without
the two or three dissatisfied students in each class, all three
questions would have average values above 4. Second, the
scores from the first class were consistently higher than
scores from the second class. Based on student comments,
this difference is largely due to greater time pressure: the
second class received only two weeks to work on the project,
while the first class received three weeks.
Some representative student comments are provided be-
low, followed by a discussion of what these comments say
about the successes and shortcomings of the COMET project.

Enjoyable Project
"This is the only project I have had at Tech that was enjoy-
able. I didn't even feel like I was doing a projectfor a grade."
"Fun project, but still learned a lot."
Many students enjoyed the project. They were surprised to
find that something educational could also be fun. Making
the connection between academic values (i.e., learning) and
personal values (i.e., fun) may be the most important lesson
of the project. Student-perceived relevance of course mate-
rial is known to be important for effective learning.'171

Hands-On Learning
"It was nice to do something in ChE away from paper and
theory."
"Home Depot is very fond of Georgia Tech students."
A number of students commented on the hands-on nature
of the project and appreciated it as a refreshing change from
conventional problem sets. The opportunity to exercise
"right-brain" thinking through an active process that yields
concrete results appeals to students with learning styles
not easily accommodated in conventional "left-brain"
classroom lectures.191

Weak Connection with Course Material
"I don't think I really learned anything from the project that
pertained to the course."
"I'd suggest allowing chemical energy sources. After all, this
is a Chem E class."
Some students were concerned that the project was not
closely related to the rest of the course material. I partially
share this concern. While the quantitative energy balance
calculations required in the final report relate directly to
material presented in lectures, the design, construction, and
testing of COMETs are not as closely linked to the rest of the
course. Nevertheless, I believe it is important to expose
engineering students to concepts like teamwork, open-ended
design problems, and hands-on experimentation, and I think
the COMET competition provided an exciting framework
Continued on page 45.











l Oclassroom
~Ccl~is~om~_


ANIMAL GUTS AS IDEAL REACTORS

An Open-Ended Project

for a Course in Kinetics and Reactor Design


ERIC D. CARLSON, ALICE P. GAST
Stanford University Stanford, CA 94305-5025


Educational researchers have identified a need to ex-
pand the typical teaching approach found in most
engineering courses beyond the lecture and problem-
set format."' Strict adherence to this traditional teaching
method has several shortcomings. First, students possess a
variety of learning styles.[2] Educational researchers have
attempted to correlate learning styles with traits such as
Meyers-Briggs Type Indicators,'[3'4 gender,'[5 and regions
where the students grew up.161 By implementing only one
teaching method, educators can lose some of their audience
and place some students at a disadvantage. Second, tradi-
tional teaching methods often do not promote the creativity
desired by most employers and researchers. Third, tradi-
tional methods of teaching do not necessarily encourage
students to develop the self-reliance essential in an industrial
job or in graduate research. In the "real world," problems do
not come out of a book, numbered and self-contained, nor do
they proceed directly from the previous day's lecture. Ulti-
mately, graduates need to be able to define their own prob-
lems and to determine what information is needed to solve
them. Finally, engineering problems sets do not emphasize
the importance of communication.
In this paper, we present an open-ended project tailored
for a senior kinetics and reactor design course. The project is
based on work by Penry and Jumars in which basic reactor
design equations are used to model the digestive system of
several animals.17] We will begin by describing the assign-
ment, will follow with the results, and will close with some
overall conclusions about the success of such a project.

THE ASSIGNMENT
We asked the students to model the digestive system of an
animal of choice as one or more ideal reactors, applying
principles from the course. There are three aspects of the
project, each with its own goal: a literature search, the devel-


opment of a model, and the communication of the model to
an audience. While the project is intended to be open-ended,
students in general do not respond well to nebulous assign-
mentst18 so we gave them our concrete expectations at the
very beginning, including specific goals to attain for each
aspect of the project.
We asked each student to choose his or her own individual
animal, thus ensuring that each model would be unique.
Individual choice also allowed the students to apply the
project to an animal they found personally interesting.
The first phase of the project focused on searching the
literature. To build a theoretical model of their animal's
digestive system, students had to acquire information about
the diet (reactant feed), the digestive process, gut size (reac-
tor volumes), throughputs, and any enzymatic and bacterio-
logical kinetic rate data from the literature. Not surprisingly,
there is an abundance on literature information of some
animals, but very limited information on others. We recog-
nized that some students would find this disparity frustrat-

Eric Carlson is a chemical engineering PhD
candidate at Stanford University, studying the
optical-rheology of elastomeric polypropylene
with Prof. Gerald G. Fuller. He earned his MS
from Stanford University and his BS from North
Carolina State University, where he was intro-
duced to the joys of cooperative learning. On
the few occasions he escapes from the lab, he
enjoys mountain biking, rollerblading, volleyball,
and poor attempts at golf.

Alice Gast is Professor of Chemical Engineer-
ing at Stanford University. She obtained her BS
from the University of Southern California and
her PhD from Princeton University. Her research
interests in complex fluids combine statistical
mechanical models of suspensions and solu-
tions with neutron, X-ray, and light scattering
experiments. Among other activities, she enjoys
regular trips to the San Francisco Zoo and
Monterey Aquarium.


Copyright ChE Division ofASEE 1998


Chemical Engineering Education













In this paper, we present an open-ended project tailored for a senior kinetics and
reactor design course. The project is based on work by Penry and Jumars
in which basic reactor design equations are used to model
the digestive system of several animals.


TABLE 1
Digestive Schemes

Animals display a variety of digestive schemes to handle available
food sources. Single reactor schemes can model simple animals with
minimal energy requirements, like
starfish. Larger animals with higher
energy requirements offer a larger S
variety of digestive schemes. Simple
Carnivores, frugivorous primates, and Small Intestine
omnivorous humans all possess a
simple stomach and small intestine to
break down high-energy food.

Some animals rely on more readily available, lower-energy foods such


Complex, Multi-
Chambered Stomach


To Small Intestine

ForePut Fermenter


as grasses and leaves. These animals
generally need the assistance of
microbes to break down food to
provide energy. Foregut fermenters
are animals in which microbial
fermentation of ingested material
precedes catalytic digestion (e.g., cows,
sheep, goats, deer, hippos, kangaroos,
whales, and manatees). Microbial
fermentation takes place in a well-
mixed rumen or complex stomach, after


which the food passes to a long, tube-like intestine where catalytic
digestion occurs.


In hindgut fermenters (e.g., horses,
rhinos, koalas, rabbits, and
elephants), microbial fermentation
takes place in the cecum following
catalytic digestion.


Stomach
Small Intestine
Cecum

Hindm ut Fermenter


ing, but we hoped they would tolerate it and rise to the
challenge once we explained the relevance of open-ended
literature searches to their education. On a mundane level,
students learned how to perform on-line searches and to
effectively use the WWW, how to find and explore appropri-
ate libraries, and what type of information is found in texts
as opposed to journal articles. At a higher level, students
learned how to select relevant facts from a large, perhaps
overwhelming, body of information. We asked that the stu-
dents turn in a concise summary of the relevant aspects of at
least three references.
Winter 1998


The next phase of the project was model development. We
asked the students to sketch the ideal reactor series em-
ployed and to present the equations used to predict conver-
sions and residence times. This portion of the project al-
lowed students to apply course knowledge to a new problem
that they devised for themselves. Based on their literature
search, they had to decide what reactor or reactor series was
appropriate, where there was essentially continuous flow,
whether mixing was ideal, and what reactions were impor-
tant. If experimental data were available in the literature,
model predictions were to be compared with experimental
values of conversions and residence times. Generally, ki-
netic and conversion data are not available for most animal
species, so students were asked to fill in the gaps with
appropriate assumptions by extrapolating data from other
related species. In cases where such extrapolation was not
feasible, students were asked to describe in detail how one
might experimentally gather kinetic data on the digestive
system to compare with their model.
Along with the model, students were asked to provide a
critique, discussing the strengths and weaknesses of their
analysis, and to describe how well it would serve to predict
reality. The critique forced the students to think about the
equations and to understand the assumptions that go into
them at a high enough level to be able to explain it to others.
The last aspect of the project was the development of
communication skills. In addition to the short summaries of
the literature articles, students had to prepare a written report
describing the model of their animal's digestive system,
including an introduction motivating the application of
the model to their animal. A small class size also allowed
the students to make oral presentations of their report.
The emphasis of the oral and written reports was on
organizing a coherent presentation of the model, its moti-
vation, and its critique.

GUT MODEL DEVELOPMENT
As stated in the introduction, this project is based on Penry
and Jumars' work using basic reactor design equations to
model the digestive system of a variety of animals and to
identify the digestive operating systems that optimize the
utilization of nutrients and the production rate of energy.171
Their reactor design models and basic kinetic rate expres-
sions can be found in most undergraduate kinetics and reac-
tor design textbooks, 9-21 making the development ideal for
25










use in the classroom. The authors discuss modeling the guts
of marine deposit feeders, mammalian hindgut fermenters,
and mammalian foregut fermenters (see Table 1).
In their analysis, the authors assume that digestive reac-
tions are homogeneous, kinetically controlled enzyme pro-
cesses in which food component A binds reversibly to en-
zyme E and dissociates irreversibly into products) P and
free enzyme:

A+E EA -P+E (1)
They further assume that all digestive reactions fall into two
main categories. Digestive reactions catalyzed by an animal's
own enzymes are described by the Michaelis-Menton kinet-
ics and follow the rate expression

VmaxCA (2)
KA +CA

where
CA concentration of A
Vmax (kCE)
KM (k++k,)/k,
Digestive reactions that rely on microbial fermentation are
autocatalytic. Microbes M are produced as food component
A is broken down. This can be described by

A+M -> MA P+M+M (3)
Such reactions have an additional dependence on the con-
centration of microbes, CM:

SVmaxCACM (4)
KM + CA
Reactor design texts[9121 derive design equations for the
three ideal reactors used in the gut analysis of Penry and
Jumars: batch reactors, plug flow reactors (PFRs), and con-
tinuously stirred tank reactors (CSTRs). The time in a batch
reactor or space time (r = V / V) in a continuous flow reactor
required for digestion to achieve a particular conversion, X,
can be found using the familiar design equations


Batch


PFR


CSTR


Final



V dX
t==CAO N -
SrA
Xo-
v =CAo -rA

Xin
V CAO(Xout -Xin)
v (-rA)out


where


reaction rate
initial number of moles of reactant A
feed concentration of A
reactor volume
volumetric flow rate of the feed


Figure 1 shows the graphical design equation for finding
the space time of an animal gut performing a catalytic diges-
tion process following Michaelis-Menton kinetics. To mini-
mize the space time, Michaelis-Menton catalytic digestion is
optimized by a PFR design. Figure 2 shows a plot of recipro-
cal reaction rate versus conversion for an autocatalytic mi-
crobial fermentation process. Autocatalytic reactions are op-
timized by a CSTR operating at the point of maximum
reaction rate, followed by a PFR.
Penry and Jumars suggest general designs for deposit feed-
ers, mammalian hindgut fermenters, and mammalian foregut
fermenters. Depending on the specific animal being mod-
eled, reactor design models may need modifications to ac-
count for various factors-such as variable flow rate, vari-
able gut volume, non-ideal mixing, recycling by means of
coprophagy (reingestion of feces), and caecotrophy
(reingestion of partially separated feces, as in rabbits)-and
residence time distributions. Modifications to the reaction
kinetics may account for different forms of enzyme kinetics,
mass-transport limitations, heterogeneous catalysis, and non-
isothermal conditions. Ultimately, fundamental reactor de-


S TPFR /






Conversion, X

Figure 1. Graphical design
equation for a
plug flow reactor (PFR).


tn j TPFR

CSTR



Conversion, X

Figure 2. Graphical design
equation for a continuously
stirred tank reactor (CSTR).


Chemical Engineering Education










sign equations can form a biologically meaningful, math-
ematical framework for the description of animal digestion.

STUDENT ANIMAL GUT MODELS
Using the tools of kinetics and reactor design and the ideas
presented in the work of Penry and Jumars, the class was
able to develop models about the digestive behavior of ani-
mals across the animal kingdom. Some animals had seem-
ingly simple digestive systems, while others had more com-
plex guts. Table 2 lists typical animals that students mod-
eled. A few of the animals were modeled with single ideal
reactors (vampire bat, sea anemone, starfish) and offered
simple systems like the deposit feeders in the article by
Penry and Jumars. Many of the animals required a series of
reactors. A student model of the hippo gut (foregut fer-
menter; CSTR-PFR) is presented below. Several students


V',=0.46m- \-=0.15m3

S L=47m
Figure 3. The familiar hippopotamus and a student
model of the hippopotamus gut
(foregut fermenter; CSTR-PFR).


Catalytic Digestion


Autocatalytic M
Fermentation


Distal Colon/Rectum
V=225mL
T=23hrs

Negligible Digestion


Figure 4. Student model of the koala gut (hindgut
fermenter; CSTR-PFR-Separator-CSTR-PFR).
Winter 1998


extended their model to account for digestive behavior dis-
tinctive to their animal, using either additional reactors or
modification of the underlying assumptions. Two prime ex-
amples are also presented below: a koala bear (hindgut fer-
menter; CSTR-PFR-Separator-CSTR-PFR) and a manatee
(hindgut fermenter; CSTR-PFR-CSTR-PFR).

Hippopotamus Hippos are foregut fermenters that
spend about five hours a day eating about 40 kg of short
grasses. The student modeled hippo digestion with a CSTR
and a PFR in series with information about the volume of the
stomach, the length of the intestines, and the feeding rate
from the literature.1131 The model is shown in Figure 3.
The volume of the intestine was calculated based on data
of the distribution of digesta between the stomach and the
intestines. Reactor volumes and throughputs allowed for the
estimation of fairly reasonable residence times: CCSTR = 3.5
days, TPFR = 1.1 days. The student suggested tracer studies to
check the accuracy of these estimates. Detailed kinetic data
were not available to calculate the actual conversions. The
student discussed how one might get the kinetic information
experimentally, either by monitoring hippos in the field,
examining hippo excrement, or by extrapolating from a
known body of data on animals with similar digestive
systems (e.g., cows). Researchers could then use the de-
sign equations and compare calculated conversions with
those found experimentally. Because the nightly feeding
of hippos only lasts about five hours, a more rigorous
model would account for the unsteady nature of the di-
gestion process.

Koala Koalas are hindgut fermenters with a unique diet.
Exceptionally picky eaters, koalas focus entirely on a select,
low-quality food source-eucalyptus leaves from only about
5 of over 100 available species. Koalas have evolved
highly specific guts to digest this food source, and reac-
tor design analysis can give insight into the importance
of nature's design.
The contents of eucalyptus cells are highly diges-
tive, according to the literature."1 The student as-
sumed that all digestion of the cell contents occurred
in the stomach and small intestine by means of cata-
lytic digestion. Microbial breakdown of the eucalyp-
tus cell wall occurs only in the cecum and the colon.
microbial
Koalas are not born with these helpful microbes, but
rather gain them from ingesting adult fecal matter
shortly after being weaned.*
The model of koala digestion is shown in Figure 4.

On a field trip to the San Francisco Zoo, the class
learned of the availability of hippo excrement; hippos
leave the water to distribute their feces rather widely to
mark their territory.
** On the same field trip to the San Francisco Zoo, we
learned of weaning and eating habits of young koalas.


v=40 kg/day, p=306 kg/m3










Literature provided the student with tracer and dissection
studies of koalas that reveal two main residence times in the
koalas' guts. The mean residence time for particulate matter
was about 100 hours, while that for the solute phase was
about 210 hours. The student decided to employ a separation
process within his model to account for these two residence
times. Because koala eating is spread fairly continuously
throughout the day between periods of sleep, the student
modeled koala digestion as a continuous process.
Using this model and literature values for throughput rate
and gut volumes, the student was able to match the experi-
mental residence times for both the coarse particles and
soluble fine particles. Unfortunately, the student was unable
to find kinetic data for these reactions; he pointed out that
kinetic data would allow one to study the digestion of koalas
with mathematical models and reduce the need for slaughter/
dissection studies.

Manatee Another
modification of Penry and
Jumars' hindgut fermenter
was presented by a student
who modeled the guts of S c
Stomach Small Intestine
manatees. A scheme of V=93L V=68L
four reactors was chosen r=42hrs T=3lhrs
to model its digestive be-
havior. The student de- Catalytic Digestion
cided that Penry and
Jumars' model of a hind- Figure 5. Student mod
gut fermenter PFR-CSTR fermenter; CS
series was a poor choice
in the case of the manatee for two main reasons: first,
manatees are known to achieve large conversions, and
large conversions that operate beyond the maximum au-
tocatalytic reaction rate are inefficient in a CSTR, and
second, the long curvaceous nature of the colon, coupled
with the viscous nature of the digesta found in the mana-
tee makes perfect mixing unlikely.
Like horses and elephants, manatees use the cecum and
colon as primary fermentation sites, whereas the stomach
and the small intestine are used for catalytic digestion.
Because both the colon and the small intestine are long and
narrow, they were both modeled as PFRs. The open cavities
of the stomach and the cecum are more amenable to CSTR
design. Thus, a CSTR-PFR-CSTR-PFR series was chosen
to model the manatee gut, as shown in Figure 5.
Equations of forms (2) and (3) were used to model the
catalytic digestion and the autocatalytic fermentation reac-
tions, respectively. CSTR and PFR behavior were modeled
using Equations (5) and (6). The student was unable to find
kinetic data specific to manatees, but she was able to find the
typical range of rate parameters VMAX and K, found in
hindgut fermenters for fermentation and catalytic digestion


el of
TR-1


processes. The only unknown variable is CM, the concentra-
tion of microbes. For the purposes of calculating general
trends, the student assumed that the microbe concentration
was directly related to the concentration of food, CA. Now,
by examining each reactor in sequence, one can calculate the
output CA and conversion.
Even with her broad kinetic generalizations, the student
found that the theoretical overall conversion fell between
60% and 80%, comparing extremely well to the literature,
which cites 45% to 70% for manatees (and about 84% for
dugongs, another species of sea cow).
As weaknesses of her model, the student cited several
factors, including the lack of true kinetic data, the assump-
tions of constant volume digesta, and complete mixing in the
CSTR compartments. This model allows one to conceptual-
ize the conversion of food, however, and illustrates the effi-
ciency of nature in de-
signing its own reactors.

X1 ANIMAL GUT
DESIGN AS A
S&X. TEACHING TOOL
-'c _____ ^c
ecum Colon Students (and instruc-
V=IL V=185L t
--0.5hrs T=84hrs tors) responded we to
this open-ended project.
Autocatalytic Microbial Fermentation It was enjoyable for ev-
eryone and it added a
unique dimension to the
the manatee gut (hindgut class. As a teaching tool,
the project was a suc-
cess on several levels. While the subjective nature of
evaluating student performance* makes it difficult to give
direct, quantitative comparisons with more traditional prob-
lem assignments, there were several indicators by which we
were able to judge this project's success.
Foremost, it was obvious that students learned from this
exercise. The project allowed students to apply kinetics and
reactor design concepts and to extend their knowledge of
course material to a unique reactor system. Based on their
own knowledge, they had to decide for themselves what
model assumptions were appropriate. The project saw the
development of several fairly comprehensive models built to
account for complex reactive and flow behavior. The in-
class presentations allowed students to present to and teach
each other about the applicability of ideal reactor models.
Not only was the project instructive, but it was also enjoy-
able to the students. Overall, student response was highly

* Students were told from the beginning that the project would
count for a non-trivial part of their grade. Evaluation would be
based on proper use of course material, exhaustiveness of the
literature search, completeness of the model based on available
information and creativity, rigorousness of the critique, and
quality of oral and written presentations.
Chemical Engineering Education


J










favorable. When asked their opinion of the course after-
wards, students responded that they "enjoyed the project"
and that it was "fun"-phrases rarely used to describe a
typical homework set.
We did receive a few less positive responses at the begin-
ning of the project. While some students liked the flexible
nature of the project, a few students worried about what was
meant by "the project's success being up to them." Several
students were initially turned-off by the idea of an open-
ended literature search. We dealt with complaints about
trying to chase down details that may or may not exist in a
large body of literature in a case-by-case manner. Ulti-
mately, the students developed searching strategies and
were able to organize the information. The open-
endedness of the project made creativity possible, which
the students all seemed to enjoy.
An additional success indicator was increased office hour
attendance. Students who previously had not shown exces-
sive interest in course material began arriving early and
asking questions. Several became quite stimulated by the
topic and would engage each other in discussion about their
models. These discussions provided an effective cooperative
learning environment in which students relied on each other
to learn and to teach the subject matter.11
Finally, students were both more creative in their problem
solving and more expressive in the discussions of their mod-
els. This project was a success as a teaching tool because its
open-endedness and active learning emphasis appealed to a
wide variety of learning styles. The open-ended project was
complimentary to more traditional problem sets in that it
allowed students to extend their knowledge beyond what
had been directly presented in the classroom.

CONCLUSIONS
Reactor design models can be successfully employed to
model the guts of a variety of animals, and the use of such
models on unique animal systems provides a stimulating
learning experience for both the students and the instructor.
We would encourage any one teaching a reactor design class
to use this or a similar type of project to engage the students
and help seize their interest.

ACKNOWLEDGMENTS

We would like to thank the students of ChE 130 from the
winter quarters of 1996 and 1997 for their participation,
enthusiasm, and creativity. In particular, we would like to
thank Sao Wei Lee for his model of the hippo gut, Dhruv
Gupta for his model of the koala gut, and Lani Miyoshi for
her model of the sea cow gut. APG would also like to thank
Deborah Penry for giving her the initial idea for this project
at the 1st Annual Symposium on German-American Fron-
tiers of Science.


Winter 1998


REFERENCES
1. Rosati, P.A., and R.M. Felder, "Engineering Student Re-
sponse to an Index of Learning Styles," Proceedings-1995
Frontiers in Education Conference, IEEE, New York, NY, p.
739(1995)
2. Felder, R.M., and L.K. Silverman, Eng. Ed., 78(7), 674
(1988)
3. Myers, I.B., and McCaulley, Manual: A Guide to the Devel-
opment and Use of the Myers-Briggs Type Indicator, Con-
sulting Psychologists Press, Palo Alto, CA (1985)
4. Rodman, S.M., R.K. Dean, and P.A. Rosati, "Learning Style
Among Engineering Students: Self Report vs. Classification
of MBTI," Proceedings-1995 Frontiers in Education Confer-
ence, IEEE, New York, NY, 48 (1985)
5. Felder, R.M., K.D. Forrest, L. Baker-Ward, E.J. Dietz, and
P.H. Mohr, J. Engr. Ed., 82(1), 15 (1993)
6. Felder, R.M., P.H. Mohr, E.J. Dietz, and L. Baker-Ward, J.
Engr. Ed., 83(3), 209 (1994)
7. Penry, D.L., and P.A. Jumars, American Naturalist, 129, 69
(1987)
8. Felder, Richard M., "Meet Your Students: 6. Tony and
Frank," Chem. Engr. Ed., 29(4), 244 (1995)
9. Levenspiel, O., Chemical Reaction Engineering, 2nd ed.,
Wiley, New York, NY (1972)
10. Fogler, F.S., Elements of Chemical Reaction Engineering,
2nd ed., Prentice Hall, New Jersey (1992)
11. Smith, J.M., Chemical Engineering Kinetics, 3rd ed.,
McGraw-Hill, New York, NY (1981)
12. Hill, Jr., C.G., An Introduction to Chemical Engineering
Kinetics and Reactor Design, Wiley, New York, NY (1977)
13. Clemens, E.T., and G.M.O. Malloy, J. of Zoology, 198, 141
(1982)
14. Cork, S.J., I.D. Hume, and T.J. Dawson, J. Comp. Physiol.,
153,181 (1983) 0



book review



INTRODUCTION TO THEORETICAL
AND COMPUTATIONAL FLUID DYNAMICS
by C. Pozrikidis
Published by Oxford University Press, 198 Madison
Avenue, New York NY 10016; $75.00 (1996)

Reviewed by
Michael D. Graham
University of Wisconsin-Madison

Introduction to Theoretical and Computational Fluid Dy-
namics is an ambitious text, attempting and largely succeed-
ing to encyclopedically cover the theoretical fundamentals
of incompressible, nonturbulent Newtonian fluid mechanics.
In addition, the book gives a flavor of the numerical methods
by which fluid dynamics problems are often solved. The
Continued on page 75.
29










"W/learning


TOWARD

TECHNICAL UNDERSTANDING

Part 3. Advanced Levels


J.M. HAILE
Clemson University Clemson, SC 29634-0909


he papers in this series* stalk the question of what we
mean by an understanding of technical material. We
have asserted that to understand has multiple mean-
ings, and we organized those meanings into a hierarchy of
seven levels: (1) Making conversation; (2) Identifying ele-
ments; (3) Recognizing patterns; (4) Solving problems; (5)
Posing problems; (6) Making connections; (7) Creating ex-
tensions. In the second paper of this series, we discussed
understanding at Levels 1 through 4, which we refer to as
elementary understandings. To progress beyond problem
solving at Level 4, we must realize that solving a problem is
not the same as knowing how to solve it. This realization
marks the beginning of the transition to the more advanced
levels addressed in this paper. The discussions here rely on
the descriptions of brain structure and function that were
summarized in the first paper of the series.


Transition:
Level 4 (Solving Problems)
to
Level 5 (Posing Problems)
Motivation: Solving a problem is not the same as knowing
how to solve the problem.
Reformulation: The initial solution procedure is refined
by rehearsal and the problem plus its solution are explored
by exercising variations on a theme.

LEVEL 5: POSING PROBLEMS
We practice problem solving not to obtain an answer, but
to learn how to solve problems. That is, implementing a
procedure to obtain an answer occupies a lower level of

* Part 1, "Brain Structure and Function" was published in the
summer 1997 issue of CEE (Vol. 31, No. 3) and Part 2, "Elemen-
tary Levels," appeared in the fall 1997 issue (Vol. 31. No. 4).


understanding than does devising the procedure. To develop
skills for solving problems, we must confront new problems,
solve them, and then solve them again and again. Repetition
allows us to shift our attention from obtaining an answer to
learning a procedure. Repetition also promotes creation of
long-term memories, which we need for reusing a procedure
in the future. The connections between repetition and memory
will be discussed first, then we will make connections be-
tween repetition and problem solving.
Posing Problems to Create Memories
Creating memories serves as one hedge against future
needs. In particular, long-term memories (certain long-last-
ing neural networks and combinations of networks) enable
us to reuse problem-solving strategies that we have found
successful in the past. At the subconscious level, we don't
know how the brain selects what ideas are to be remem-
bered. That is, in spite of popular wisdom, the brain does not
lay down a memory for every mental state nor for every
sensory experience; on the contrary, most pass through short-
term memory and are lost. But we do know that we can
consciously select what ideas are to be remembered and
we can consciously create those desired memories; the
operative mechanism is repetition-repeatedly thinking
about the ideas.
Repetition causes the cortex to repeatedly fire the same
pattern of neurons; such repeated activations appear to
strengthen synaptic junctions and perhaps develop new junc-
tions. Thus, by repeated use, a track through a wilderness
becomes a path, then a walk, and finally a highway. More-
over, besides strengthening connections, repetition also seems
to refine the neural network that reproduces the desired

J.M. Haile, a professor of chemical engineering at Clemson University, is
the author of Molecular Simulation, published by John Wiley & Sons in
1992.
Copyright ChE Division ofASEE 1998
Chemical Engineering Education









firing patters-it makes the network more efficient. When
the mind contrives a pattern for a new idea, it seems to arise
"on the fly"-the new thought is hastily thrown up as a
permutation of an existing pattern. If a new idea seems
interesting or important, and therefore worth remembering,
then repeatedly thinking about it may create
a new network that is largely separated from
the parent network but connected to other 1
networks that represent related ideas.
Perhaps a helpful metaphor here would be real
scaffolding. A new, hastily constructed, net- SOlving
work is a fragile thing, momentarily stabi-
lized by a scaffolding of neural connections is not tf
that allow us to examine the new idea. If the
idea is judged worthy, then we use repetition knowil
to strengthen important synaptic junctions in
the network and remove the scaffolding. Of- solve
ten, the scaffolding is produced by studying
the intermediate details that appear in any realizal
logical development, such as those that con-
nect a conclusion to a hypothesis, those that the be
relate an effect to a cause, and those that the fra
connect an answer to a problem statement.
Without intermediate details, scaffolding is the
sparse or nonexistent, and student under-
standing remain poorly developed. Rep- advand
etitions make such connections at first
plausible, then acceptable, and finally ob- address
vious-these correspond to stages in re-
moving the scaffolding. p(
Repetition also serves to distinguish pro-
cedural memories from episodic memories.
Procedural memories are created by conscious practice, while
episodic memories are apparently created from a single ex-
perience. How might episodic memories be formed? Deep in
the brain, forming part of the limbic system, is the hippo-
campus-a pair of structures whose shapes each resemble
that of a sea horse. If a hippocampus is damaged or removed,
we lose the ability to form new long-term memories; old
memories remain, but new ones do not form. Thus, the
hippocampus plays some crucial role in forming long-
term memories. Further, it communicates with the cortex
through two bundles of axons, one apparently for input
and another for output. This suggests that the hippocam-
pus may act, in effect, as a buffer between short-term and
long-term memories.111
Perhaps when many networks in the cortex are busy-
attacking a hard problem-the cortex is too preoccupied to
continue the structural changes that produce long-term memo-
ries. Perhaps, instead, networks in the hippocampus are acti-
vated, loading the buffer. Later, when networks become
available in the cortex (perhaps during rest, or sleep), the
hippocampus "replays" important patterns in the cortex,
Winter 1998


thereby creating long-term memories in the cortex.121 If such
a scenario is true, then all memories are formed by repeti-
tion; the difference between procedural and episodic memo-
ries is merely that procedural memories are created by con-
scious repetition, while episodic memories are created be-
low consciousness via repetitions instigated
Sby the hippocampus.


we must

ize that

a problem

ie same as

ng how to

it. This

tion marks

ginning of

msition to

'more

ced levels

sed in this

paper.


Thus, part of our activity during rehearsal is to probe and
verify the logic of the algorithm; such activity conforms to
Poincar6's statement that in a chain of logic, the order of the
elements is more important than the elements themselves.*
Another part of rehearsal is the search for a better algorithm.
That is, problems are interesting and instructive to the extent
that they can be solved in more than one way. Problems can
themselves be viewed as patterns with their multiple mean-
ings reflected in the various ways by which they can be
solved. By repeatedly posing the same problem to ourselves,
we create opportunities for finding alternative solution pro-
cedures and therefore for finding additional meanings.
A powerful motivation for rehearsal occurs when we in-
tend to present the solution to others-perhaps as a lecture or
as a written document. Such presentations are most effective
when the chain of logic is economical, with every element
moving the development in an obvious way toward the goal.
Such presentations are developed by rehearsing, wherein we
systematically try to reformulate a logical development into
*See Level 3 in Paper 2, Chem. Eng. Ed., 31(4), 1997).


Posing Problems by Repetition
We invest time and effort in learning so as
to realize future benefits; this implies that
we intend to remember what we learn. Prob-
lem posing is the level of understanding at
which we use repetition for learning how to
solve problems and for creating memories of
the solution procedure. We identify two kinds
of repetition: rehearsal, in which we repeat-
edly pose and solve the same problem, and
variational, in which we pose and solve
new problems that are closely related to
the original problem.
Rehearsal* Having solved a problem, we
rehearse the procedure to learn how we solved
it. Since we know that the procedure leads to
the solution, our minds during rehearsal are
free to consider (1) why each step is impor-
tant and how it contributes to the solution,
(2) whether alternative steps may be more
economical, and (3) whether the steps and
intermediate results can be connected to other
things we know, thereby attaching additional
meanings to the procedure, the solution, and
the problem.


II










a sequence that is not only economical but also rich in
meaning. Minsky'13 has emphasized that reformulation is the
central act of creativity. For example, in spite of the common
attitude that rehearsal is merely mechanical repetition, the
rehearsal involved in preparing lectures and writing text-
books provides opportunities for high levels of creativity
and originality.31'
Variational Besides repeatedly posing the same prob-
lem, we should also pose and solve other problems that we
create by systematically changing the original problem. Thus,
we enhance problem-solving skills by posing variations on a
theme. This activity is analogous to a practice technique
used by musicians. Consider the passage from Chopin's
third Prelude (Opus 28) for piano, shown in Figure 1. This
one measure is scored as a phrase-a musical pattern of
sixteen notes. The third Prelude is marked vivace, which
means a lively allegro, and corresponds to a speed of about a
measure per second. In fact, a measure per second would be
a little slow; five measures in four seconds would be more
nearly correct. Thus, each of the sixteen notes should be
sounded at a uniform interval of about 5/100 of a second.
How is such skill developed? Not simply by repeatedly
playing the measure as written, but rather by practicing
rhythmic variations, such as are also shown in Figure 1.
Each variation shifts the emphasis to a different note, hence
a different finger; additional variations would be used to
shift the emphasis among different groups of notes. The
figure shows only three variations, but in practice, the musi-
cian routinely works through 40 or 50 variations of the same
phrase. And those are just the rhythmic variations; one also
works through variations in tempo and in dynamics (loud-
ness). It may seem paradoxical that to achieve what the
composer has written, one practices something other than
what is written, but such practice proves to be an effi-
cient way to attain absolute control over the material; to
embed a metaphor within a metaphor, a chain is made
stronger by systematically and repeatedly strengthening
one link at a time.
Likewise, we can improve our grasp of and control over
technical material by posing variations on the theme inher-
ent in any problem. Say the original problem requires us to
obtain the volume V occupied by one mole of nitrogen at P =
2 bar and T = 500C. Having obtained the answer, we can
systematically vary that problem to create somewhat differ-
ent, but related, problems to solve. For example: (1) What
would V be if T were 1000C instead of 500C? (2) What
would V be if P were 3 bar at 500C instead of 2 bar? (3)
What would V be if we had 5 moles instead of one at 50'C, 2
bar? (4) Can we generalize what we've learned from these
four calculations? (5) What if we knew N, V, T and needed
to find P? (6) What if we knew N, V, P and needed T? (7) If
the gas were a binary mixture of nitrogen and oxygen, what
would change in all these calculations? (8) What if the gas


Original







Variation A







Variation B
> > 4 >






Variation C

i i



Figure 1. Three rhythmic variations on the first measure of
Chopin's Prelude for piano, Opus 28, No. 3. On each staff,
horizontal lines and spaces between them represent keys
on the keyboard; notes indicate keys to be struck. On each
of the four staffs, the same keys are to be struck; thus, each
staff contains the same pattern of notes. But the variations
differ from the original and from one another in that they
require keys to be struck with different amounts of force
and held for different amounts of time. In an analogous
manner, engineering students can exercise their under-
standing of technical material by repeatedly using the
same pattern of information, but emphasizing different
aspects of the pattern; that is, they can pose and solve
several variations on a problem originally assigned by
their instructor.

were a twenty-component mixture? (9) Presumably, we have
used the ideal-gas law in these calculations, so by what
criteria do we decide that the ideal-gas law no longer ap-
plies? (10) When the ideal-gas law doesn't apply, what
should we use instead?
Note that the original problem has led us to devise ten
variations-effectively, ten new problems. This process is
most effective if students are merely shown the strategy and
they create their own variations. Hopefully, they eventually
create problems that they don't know how to solve, then they
initiate a dialog with the instructor. This process is system-
atic and can be applied to any problem; in fact, rather
than solving 100 different problems, students seem to
Chemical Engineering Education










gain more by solving ten problems plus ten variations of
each. More on variational problem posing can be found
in a book by Brown and Walter.'41
Earlier we noted that reformulation is a central aspect of
creativity; this observation can now be pushed farther by
noting that devising variations on a theme is itself a reformu-
lation. Hence, as Hofstadter has discussed,l'] variations on a
theme is the crux of creativity. Any new object, process, or
idea is created by modifying, to a greater or lesser extent,
existing objects, processes, and ideas. (There is, after all,
nothing new under the sun.) This aspect of creativity un-
doubtedly reflects the way minds work-not by spontane-
ously creating a completely new neural net, but rather by
continually modifying existing assemblies of neurons.
But the lesson here is that in practicing variational rep-
etition on solved problems students practice creating new
things. And even though their first attempts are mundane
and uninteresting, the habit, once acquired, can eventu-
ally serve them well.


Transition:
Level 5 (Posing Problems)
to
Level 6 (Making Connections)
Motivation: Having learned to solve a problem, we should
then ask whether that knowledge can be applied to other
problems within the same domain and to analogous prob-
lems in other domains.
Reformulation: Pattern, problem context, and solution are
generalized to other domains.

LEVEL 6: MAKING CONNECTIONS
The understandings gained at Level 5 can require substan-
tial effort and labor because they often require us to make
substantial modifications to dendritic trees and neural net-
works. So once such modifications are made, we try to
increase their usefulness by connecting them to other net-
works that represent other patterns and problem contexts.
That is, we try to project our newly acquired understandings
into other domains of knowledge. Sometimes ideas for cross-
domain connections can be evoked by posing a simple heu-
ristic: Having solved the immediate problem, can we now
solve a similar problem or an analogous problem? But more
often, we must employ cross-domain devices to help us find
ideas that transcend domains. Cross-domain devices are re-
lations, patterns, or procedures that are invariant under
changes of context; thus, they can be extracted from one
context and inserted into another. Such devices provide pow-
erful ways to increase understandings, and therefore it is
probably not surprising that relatively few of them are known.
We are always seeking to add new cross-domain devices to
our repertoire, for every such device gives us another way to
Winter 1998


learn. Five common cross-domain devices follow.
(1) Our most powerful cross-domain device is mathemat-
ics. This statement often surprises students, for they tend to
view mathematics as a tool for computation. But the real
value of mathematics is that its rules for reasoning are inde-
pendent of context: mathematics is powerful because it is
abstract. As a simple example, consider the exponential
growth law
y=yoe"
where a may be positive or negative. This one equation
applies to certain processes in a number of very different and
unrelated contexts. For example, it describes the decay of
radioactive isotopes, the variation of density with altitude in
a stagnant isothermal atmosphere, the growth of a popula-
tion in a limitless environment, the cooling of a warm body
in cooler surroundings, and the growth of capital in an inter-
est-bearing investment.
(2) A second device for extending ideas across domains is
provided by scaling laws. These devices exploit the extent to
which certain behaviors are universal-independent of con-
text-when variables describing phenomena are scaled ap-
propriately. Thus, we have the many dimensionless groups
that correlate fluid flow and heat transfer in transport phe-
nomena, we have corresponding states ideas for correlating
thermodynamic properties, and we have scaling laws for
describing the behavior of materials near critical points.
More generally, we now have numerous disparate phe-
nomena, referred to collectively as fractals, that are invariant
under changes of scale. For example, the Brownian motion,
first described by Robert Brown in 1828, originally referred
to a microscopic scale; when viewed through a microscope,
a minute particle displays random movements caused by
collisions with molecules of the surrounding medium. But
such movements are also observed on macroscopic scales in
colloidal suspensions and on galactic scales in the motion of
stars in open clusters, such as the Pleiades.
(3) Another effective way to cross domains is by using an
analogy: the presumption that if two things have certain
similarities, then they also have other similarities. Analogies
can be structural or functional, and it is wise to keep clear
which you intend in a particular case; the common pitfall is
to assume that structural similarities imply functional simi-
larities. Examples of fruitful analogies include those among
the linear transport laws of Newton, Fick, Fourier, and
Ohm. In thermodynamics, certain phase diagrams for
vapor-liquid equilibria are structurally analogous to dia-
grams for liquid-solid equilibria. And in process control,
artificial neural networks bear certain functional analo-
gies to biological neural networks.
(4) Still another device is the metaphor, which we use to
describe an unfamiliar thing in terms of some more familiar
thing. Unlike an analogy, a metaphor typically attempts to










relate two things that have neither structural nor functional
similarities. Minsky has emphasized that we typically use
spatial forms and concrete objects as metaphors for abstract
ideas and concepts.J31 For example, we talk about an idea
being solid, firm, fluid, or off-the-wall. More generally, we
have family trees, the tree of life, the tree of knowledge,
dendritic trees, and logic trees; we have roots of a family, the
root of an idea, the root of the matter, the root of a prob-
lem, and the root of all evil; we have bridges between
domains of knowledge, the bridge of time, a bridge over
troubled water, and a bridge (no less) to the 21st century.
One of the most compelling metaphors of recent years
has been that of the desktop for manipulating operating
systems on personal computers.
(5) The last cross-domain devices we mention here are
various graphing templates for representing relations. The
most common is a simple x-y plot, which shows how an
effect is correlated with its cause. To have something less
familiar, we show in Figure 2 examples of an interaction
square,[31 which shows how two causes either reinforce or
compete in contributing to a single effect. In the first and
third quadrants of the square, the two causes act together to
either amplify (quadrant I) or suppress (quadrant III) the
effect. The interesting behavior occurs in the second and
fourth quadrants, in which the two causes compete. If we
have a mathematical relation for how the two causes contrib-
ute to the effect, then we can usually solve for the locus
along which the two causes exactly compensate for one
another. This locus transverses the second and fourth quad-
rants. A particular example appears in the bottom of Figure
2, which shows how temperature and flow rate contribute to
a particular value of the Reynolds number for fluid flow.
In the discussion of Level 3 (Paper 2 of this series), we
observed that organizing knowledge into patterns provides a
mechanism for improving the efficiency of education. Un-
derstanding at Level 6 provides a similar opportunity for
efficiency. At this level our intention is to find existing
neural structures created in one context and apply them to
problems in other contexts. When this can be done, we avoid
much of the laborious effort required at Level 5 in making
major structural changes to old networks.
Transition:
Level 6 (Making Connections)
to
Level 7 (Creating Extensions)
Motivation: Having learned to recognize and solve analo-
gous problems in various domains, we should ask what
problems can still not be solved, but which might be solved
if we could extend, modify, or reformulate what we have
learned.
Reformulation: Generalizations are modified to attack other
problems.

34


Effect
Suppressed


LEVEL 7: CREATING EXTENSIONS
At Level 6, our understanding is sufficient for us to realize
that a certain pattern, problem, or procedure, devised in one
context, can be useful when transplanted in toto to another
context. At Level 7 we realize that a complete transplant will
not be useful, but if the pattern, problem, or procedure is
modified, then the transplant will bear fruit. In some situa-
tions, the necessary modification can be generated by merely
devising a variation on a theme, but more likely, we need a
reformulation that is more elaborate than a simple variation.


amplify





Cause B




suppress


Effect
Amplified


-- amplify


suppress 4 Cause A


-50 -25 0
T(C) T,


Figure 2. (Top) Generic template for an interaction square
that shows how two causes, A and B, contribute to one
effect. (Bottom) A particular example, showing how tem-
perature and flow rate combine to maintain the Reynolds
number at 104 for water flowing through a 2.54-cm pipe. If
the water temperature increases from the nominal condi-
tions of To = 500C at uo = 0.72 f/s, pushing the operating
point into the shaded region, then the desired Re can be
regained by adjusting a supply value to decrease the flow.
Inversely, if the temperature decreases from T,.

Chemical Engineering Education


25 50


3










That is, we are seeking a homomorphic projection across
domains-a projection that identifies the essential features
and that suppresses the inessential details.
An example is Maxwell's development of his theory for
electromagnetic fields, which grew out of an analogy with
vortices created in rotating incompressible fluids, as de-
scribed by Helmholtz and Thomson. Here is Maxwell re-
viewing some of Thomson's papers on electrostatics and
magnetism:161
.. illustrations of magnetic force are not put forward as
explanations of magnetic force .... They belong more properly
to that remarkable extension of the science of hydrokinetics...
(The first italics is Maxwell's; the second is mine.)
Creating extensions is a first step in the more general topic
of pattern posing and as such it links the study of established
patterns to the research involved in creating new patterns. A
principal strategy for posing new patterns is to shift, remove,
or otherwise violate boundaries. By boundaries, we mean
the assumptions and preconceptions that are inherent in any
established pattern, concept, or procedure. Even experimen-
tal work involves assumptions; that is, we design an experi-
mental protocol involving certain pieces of equipment under
the preconceptions that certain phenomena will be observed
and not others. But bounds serve as barriers that limit our
thinking. So when a problem does not yield to attacks using
established patterns and procedures, then we should test the
bounds-examine our assumptions and preconceptions. As
Root-Bernstein has noted,[17 in such situations it's not the
problem that causes our lack of comprehension; rather, the
impasse arises from assumptions that we take for granted.
Bounds are a product of negative thinking. Up to now, this
paper has focused on positive thinking-on identifying ways
to promote firing of useful patterns of neurons. But the brain
has both inhibitory and excitatory synapses, so not only can
we learn productive ways to think, but we can also learn to
avoid unproductive ways to think. By imposing bounds on
positive thinking,13' negative thinking helps us be more ef-
fective because it helps us avoid wasting time on unproduc-
tive and counterproductive trains of thought. But we don't
want the bounds produced by negative thinking to be too
rigid because creative extensions can sometimes be found by
shifting those bounds or by recognizing that some bounds
have been misinterpreted or are inappropriate. Achieving
a balance between positive and negative learning requires
a delicate hand on the part of the instructor, for overem-
phasis on negative thinking can easily suppress creative
impulses in students.
Lastly, note that violating bounds-juxtapositioning the
incongruous-is a principal attribute of intellectual humor.
Indulgence in intellectual humor exercises the mind in vio-
lating bounds and produces combinations of thoughts that
might otherwise remain unconnected. It is a conceit of mine


that such exercise preserves some flexibility in neural net-
works, and it might-just might-represent some lowly prac-
tice at creating extensions.

CONCLUSIONS
In this series of papers, we have presented a strategy for
studying technical material; the strategy is organized into a
hierarchy of seven levels. We enter the hierarchy at Level 1
when our attention is drawn to a topic and we begin to pose
questions about it. We leave the hierarchy, as it applies to a
particular topic, at Level 7 when we begin to consider how
the topic's objects and concepts can be modified so that
they can be applied to other topics. Note that problem
solving, at Level 4, occupies the central level in the
hierarchy, but problem solving is neither the goal nor
terminal point of the hierarchy.
An overriding theme of these papers has been that any-
thing interesting or useful has multiple meanings, and under-
standings of those meanings arise out of connections: con-
nections among objects and concepts to form meaningful
patterns, connections between patterns and a problem con-
text, connections among different problems and their con-
texts, and connections among different domains of knowl-
edge. The hierarchy of understanding provides a scheme for
systematically making connections. The hierarchy can be
used by instructors to help organize how material is pre-
sented to students and to help assess student understanding.
Similarly, it can be used by students to help organize their
study of a topic, to assess their comprehension, and to iden-
tify what should be done to move to the next level.
We have devoted considerable effort in trying to find
meanings for the word understanding. Perhaps some addi-
tional insight can be gained by inverting the issue and identi-
fying things that are not understanding:
1) Verbal fluency is not understanding-people can en-
gage in conversations about a topic without being able
to answer questions about the topic or to explain the
topic to others;
2) Experience is not understanding-people routinely use
automobiles and computers without understanding how
such things work;
3) Solving a problem is not understanding-people can
solve a problem without realizing how they solved it
and without being able to explain their procedure;
4) Making predictions is not understanding-before 500
B.C., the ancient Babylonians had correlated sufficient
observations so that they could predict lunar eclipses,181
but they could not explain the geometry that causes an
eclipse;[9'
5) Accumulated knowledge is not understanding-the
Nobel laureate Albert Szent-Gyorgyi once remarked
Continued on page 39.


Winter 1998










r M classroom


HELPFUL HINTS

FOR EFFECTIVE TEACHING


ROBERT H. DAVIS
University of Colorado Boulder, CO 80309-0424


A few years ago, when I was new as Chair of Chemi-
cal Engineering at the University of Colorado, my
colleagues and I felt the need to take action to
improve our teaching. The idea was born, in part, out of a
sense of frustration in trying to communicate effectively
with students in the face of increased enrollments in our
courses at the time.
As a starting point, we held a brainstorming workshop
attended by (nearly) all faculty. We next formed small groups,
each with the same task of making a list of effective teaching
attributes. Each group then presented its findings, which
were discussed and organized into four categories:
Course Organization and Preparation
Classroom Communication
Rapport with Students
Assignments, Examination, and Grading
In preparation for our workshop, I prepared a handout of
hints for effective teaching that I later revised with the in-
sights gained from the workshop. Since it is easy to lose
focus of our primary responsibility as educators and to fail to
set aside ample time for helping our students learn, I make it
a habit to review these hints several times a year. I have also
given this handout to our all of our faculty.
What follows is the most recent version of the handout,
with annotations in italics added for this article. The reader
should understand that it is not a systematic or complete


Robert H. Davis is the Patten Professor and
Chair of Chemical Engineering at the Univer-
sity of Colorado. He received a BS degree
from the University of California at Davis, and
his MS and PhD degrees from Stanford Uni-
versity. His research and teaching interests
are in fluid mechanics, membrane separations,
and biotechnology.


scholarly work on teaching, but rather one that has evolved
from my experiences and those of my colleagues. In this
sense, it has a similar flavor to several other recent
articles"l-3J on personal perspectives, and many of the conclu-
sions are ones of common sense and experience. I encourage
the reader to also consult more thorough studies and discus-
sions of teaching methods and learning styles.'14-6

COURSE PREPARATION AND ORGANIZATION

A Ask to teach courses related to your expertise. Your
knowledge of the material and your enthusiasm, both
ingredients of effective teaching,"71 will be highest in
such courses.
A Outline the entire course in advance. A logical presen-
tation of the material will be most effective if you decide
up front what the course learning goals are, what topics
are to be covered, and how much time should be spent
on each topic, and then prepare a detailed (two to four
pages) numbered outline that is used throughout the
course.
A Prepare well-organized notes for each class period. It is
easy to get into (and hard to get out of) the pattern of
preparing for a class the night before (or even the same
day). While this approach works for some of my
colleagues, I am more relaxed if Iprepare a week or
more in advance.
L Set aside at least thirty minutes right before each class
period to review the materials and to focus your
thoughts.
L Read and assimilate several sources in addition to the
assigned text. Your course should have your personal
touch and should be prepared in a style and sequence
that makes sense to you, rather than just following a
text. I recommend that you go through several books,
journals, popular press, and notes from other faculty to


Copyright ChE Division ofASEE 1998


Chemical Engineering Education











In preparation for our workshop, I prepared a handout of hints for effective teaching
that I later revised with the insights gained from the workshop.... I make it
a habit to review these hints several times a year.


select your materials.
[ On the first day of class, give the students a course
syllabus that includes the course goals, an outline,
reading assignments, homework expectations, exam
schedule, and grading policies.
[ On the first day of class, and periodically throughout
the term, discuss the relevance of the course material to
practical applications and to the rest of the curriculum.
If we want students to learn, then we must provide
motivation on why the material is important.17' Even
better, ask them to brainstorm on real-life applications
and tie-ins with other courses, either in small groups or
in an open-class discussion.
[ Provide and discuss review sheets prior to each exam.
These help the students see the big picture of what they
(should) have learned and how it ties together.
L Your course outline, notes, and materials should be
reviewed and updated each time you teach the course.


CLASSROOM COMMUNICATION


[ Put an outline on the board and provide a preview at the
beginning of each class period, whether giving a lecture
or using another style; use a brief review of the previ-
ous class period as a transition.
L Summarize the key points, with the help of students, at
the end of each class period.
A Come to class well prepared and undistracted, so that
you are less likely to stumble over derivations or
solutions. If you do make a mistake, admit your error. If
you get stuck, promise the students that you will find the
answer for next time; do not bluff "'
A Do not read your notes to the students. Simply reading
lecture notes or from a book is a sure way of turning off
the students' learning processes.1'8 While some gifted
faculty can deliver an entertaining and factual lecture
with no written materials, I am most comfortable with a
middle-of-the-road approach where I bring about five
pages of handwritten notes to a 50-minute class
period-about half of them represent material that I put
on the board for the students and the rest is highlighted
prompts to me on questions, illustrations, stories, etc.
A Write neatly on the board or overheads, use visuals, and
give students sufficient time to take notes. Board use


shouldfollow an orderly and logical progression, the
physical layout of which should be visualized in
advance, and include numbered headings consistent
with the course and class outlines. Visuals (pictures,
drawings, graphs, charts, etc.) are excellent learning
tools.1J7 When using overheads, it is especially impor-
tant to give students time to write down what is neces-
sary-or to provide them with copies of the overheads. I
like a mix of writing on the board for the main part of
the lecture, interspersed with breaks where I pass out a
one-page handout of an example or derivation that I
then go through quickly using an overhead.
[ Ask questions in order to maintain the students' focus
and assess their understanding of the material. Well-
formulated questions should stimulate the students'
thought processes.101 Give the students plenty of time to
answer the questions, and provide prompts or hints, if
necessary. I sometimes call on students by name; this
must be done with courtesy and respect, as some
students prefer to remain in the background. A student
must never be embarrassed or ridiculed for not
knowing the answer.
i Use examples in class that students can relate to. In a
heat-transfer course, discuss why the same temperature
"feels different" in dry air, humid air, water, and wind.
In a fluids course, calculate how much the shower
temperature will go up when the toilet is flushed, and
suggest an alternative plumbing design that minimizes
this effect.
A Start and end the class period on time, and gently but
firmly maintain order.

RAPPORT WITH STUDENTS

[ Learn each student's name. While this is more difficult
with larger classes, suggestions include asking each
student to write a short biographical sketch on the first
day of class, taking photographs, handing back
homework individually just before the start of class,
greeting students by name, and asking students their
names when you don't know them.
( Schedule at least two office hours or optional-help
sessions per week at times available to the students.
One should be the day before an examination is held or
homework is due, and the others) earlier in the cycle.


Winter 1998









Most important, be present for your office hours and
inform the students and reschedule those times for
which there are unavoidable conflicts.
A Be willing to see students outside scheduled office
hours and help sessions. One of the most difficult issues
we face is how to make availability to students a high
priority when there are so many other demands on
faculty time. When students drop by, my intention
(though I often fall short) is to set other things aside
and listen and help. If meeting their needs will take
longer than I can spend at that time, then I set up an
appointment. To make the necessary uninterrupted time
for writing and other tasks, I come in early; others may
prefer to stay late or spend part of the day working at
home.
[ Be attentive and sympathetic to students; do not say
anything that might make a student feel put down,
either in public or in private. The most common student
complaints that I receive as Department Chair is that
they have not been treated with respect by faculty.
While insensitive words or actions are often unin-
tended, we must never lose sight of our calling to serve
and encourage our students.
[ Take at least one class period, or parts of two or more,
to dispense with the course material and discuss a
subject such as professional ethics or your own experi-
ences.
[ Solicit and respond to mid-course feedback by a group
interview or evaluation questionnaire. Using class
representatives or peer evaluation can also yield useful
feedback while there is still time to make changes.13'"
A Provide food. At help sessions, during special occa-
sions in class, or for an end-of-term party.
A Understand that relationships with students do not end
with the course. If you show students that you care, then
they will naturally ask you to write recommendations
and provide career advice. 2' Some will come to you
with personal problems (know when to seek help from
campus professionals). Some will stay in touch for
years. These are some of the responsibilities and
rewards of our profession.


ASSIGNMENTS, EXAMINATIONS,
AND GRADING


[ Inform the students of the course grading scale or
method at the start of the course. The second most
common complaint that I receive from students involves
grades-that they were not informed by the instructor
that a certain exam would make up half of their grade,
that they were not told what performance was required
to get a "B" in the course, or that a friend received a


higher grade with the same or lower scores.
" Make sure that the exam problems correspond to the
course objectives and learning goals, which should be
the major topics of the class periods and homework
assignments. Students learn more when they are
actively involved,"' and one of the best activities is
homework on carefully selected problems.
" In each assignment and examination, include a mix of
simple, medium, and difficult problems. Since students
learn and demonstrate knowledge in different ways, it
helps to include a variety of exercises.[71
A Develop solutions for all homework and exam ques-
tions before they are handed out, and work the prob-
lems yourself. Not only does this serve as a check that
the problems are reasonable, but it also gives you the
necessary preparation for answering questions.
A Grade as thoroughly as time allows, providing com-
ments and partial credit. Careful grading is needed for
fairness and consistency, and it provides important
feedback to the students. This requires time; if neces-
sary, use this article to help convince your department
to invest adequate resources in graduate and under-
graduate course assistants.
L Return graded homework, exams, and reports promptly.
Students want feedback.171 More important, prompt
grading shows students that they are a high priority.
These hints for effective teaching can be summarized in
one word: time. It takes time to prepare a course well; it
takes time to know students. If we care deeply about stu-
dents and their learning, then teaching will be a high priority
among our other responsibilities and we will take the time to
do it well.

REFERENCES
1. Bird, R.B., "Seven Rules for Teaching," Chem. Eng. Ed.,
27(3), 164 (1993)
2. Turian, R.M., "The Quest for Excellence in Teaching," Chem.
Eng. Ed., 27(4), 182 (1993)
3. Bowman, C.N., "Teaching in the First Few Years," Chem.
Eng. Ed., 28(4), 280 (1994)
4. Wankat, P.C., and F.S. Oreovicz, Teaching Engineering,
McGraw-Hill, New York, NY (1993)
5. McKeachie, W.J., Teaching Tips:A Guidebook for the Begin-
ning College Teacher, 8th ed., D.C. Heath & Co., Lexington,
KY (1986)
6. Kolb, D.A., Learning Style Inventory, McBer and Co., Bos-
ton, MA (1985)
7. Wankat, P.C., "What Works: A Quick Guide to Learning
Principles," Chem. Eng. Ed., 27(2), 120 (1994)
8. Wankat, P.C., "Synergism Between Research and Teaching
in Separations," Chem. Eng. Ed., 30(4), 202 (1997)
9. Felder, R.M., "Things I Wish They Had Told Me," Chem.
Eng. Ed., 27(2), 108 (1994)
10. Felder, R.M., "Any Questions?" Chem. Eng. Ed., 27(3), 174
(1994)
11. Brent, R., and R.M. Felder, "It Takes One to Know One,"
Chem. Eng. Ed., 30(1), 32 (1997) 0


Chemical Engineering Education











Toward Technical Understanding
Continued from page 35.

that during his study of muscular action he came to
realize that the more he learned, the less he understood,
and so he became fearful of finally learning everything,
but understanding nothing.[10
The discussions here raise many questions that would
seem to serve as starting points for further, more detailed
investigations. Here is a list of some of the more obvious
ones.
1. If the pattern can indeed serve as the fundamental unit of
understanding, then what are those patterns that distinguish
one topic from another? For example, what patterns distin-
guish transport from thermodynamics and thermodynamics
from reaction kinetics? Then, by extension, what patterns
distinguish chemical engineering from chemistry and from
other engineering disciplines?
2. Repetition is necessary to solidify certain kinds of under-
standings, and therefore some amount of redundancy needs
to be incorporated into a curriculum. But efficiency in edu-
cation can be attained by appealing to patterns and other
devices that cross subject domains. To what extent can a
curriculum be made more effective by organizing it around
patterns rather than topics?
3. What are appropriate cues that will activate, in student
brains, proper patterns and homomorphic projections needed
to address particular problem situations? Are there mini-
mum numbers of cues that are sufficient?
4. Can we contrive a complete list of devices for making
connections across subject domains? Is there a minimum
number of such devices that a student should be able to use?
What are the most effective ways for students to develop
facility with cross-domain devices?
5. Can we devise systematic procedures for identifying and
testing default assumptions and probing tacitly assumed
boundaries?
6. Are there ways to gauge the importance and impact of
negative thinking relative to positive thinking?
7. What indicators can we devise for determining when stu-
dents successfully make a transition from one level of un-
derstanding to another?
8. Presumably, we do not expect all students to achieve the
same levels of understanding. What levels are appropriate
for BS students? For MS students? For PhD students?
9. Traditional descriptions of brain function use time to iden-
tify two kinds of memories: short-term (you look up a
phone number and remember it only long enough to dial it)
and long-term (you still remember your name). But recent
evidence suggests a third: intermediate-term memory, in
which a buffer (perhaps the hippocampus) is loaded while
structural changes are made in the brain to lay down the
corresponding long-term memory. Thus, students who cram
before a test often do not retain the crammed information
because they are only loading a buffer, not creating long-
Winter 1998


term memories. This suggests that simple linear progres-
sion through material over a semester may not be as effec-
tive as some cyclic procedure in which important patterns
are revisited at intervals. Revisiting amounts to repetition,
which stimulates creation and solidification of long-term
memories and pares away superfluous scaffolding. If this
conjecture were confirmed, what kinds of cyclic presenta-
tions should be used? What are the optimum times between
re-exposure to the same patterns?
10. Finally, note that throughout these papers we have empha-
sized what rather than how. So, how do we help students
progress through a hierarchy of understanding?

Understanding never ends.
Minsky131


ACKNOWLEDGMENTS
Many of the ideas presented in this series were tested and
clarified by continually referring to Marvin Minsky's book,'31
The Society of Mind; without that book, these papers would
have taken a very different form. Over the years of my
struggle to understand understanding, I have learned much
from discussions with my colleagues R.W. Rice
(Clemson) and J.P. O'Connell (Virginia); my thanks for
their forbearance.

REFERENCES
1. Rolls, E.T., and A. Treves, "Neural Networks in the Brain
Involved in Memory and Recall," Progress in Brain Res.,
102,335(1994)
2. Calvin, W.H., The Cerebral Code, MIT Press, Cambridge,
MA (1996)
3. Minsky, M., The Society of Mind, Simon and Schuster, New
York, NY (1986)
4. Brown, S.I., and M.I. Walter, The Art of Problem Posing,
Erlbaum, Hillsdale, NJ (1983)
5. Hofstadter, D.R., "Variations of a Theme as the Crux of
Creativity," in Metamagical Themas, Basic Books, Inc., New
York, NY (1985)
6. Maxwell, J.C., "Review of Reprint of Papers on Electrostat-
ics and Magnetism by Sir W. Thomson," in The Scientific
Papers of James Clerk Maxwell, Vol 2., W.D. Niven, ed.,
Cambridge University Press, Cambridge (1890); reprinted
by Dover Publications, New York, NY, p. 301(1965)
7. Root-Bernstein, R.S., Discovering, Harvard University Press,
Cambridge, MA, p. 296 (1989)
8. Neugebauer, O., The Exact Sciences in Antiquity, reprint of
2nd ed., Harper & Brothers, New York, NY (1962); 1st ed.,
Princeton University Press (1952); 2nd ed., Brown Univer-
sity Press (1957)
9. Toulmin, S., Foresight and Understanding, Indiana Univer-
sity Press, Bloomington, IN (1961); cited in D.A. Crosby and
R.G. Williams, "Creative Problem-Solving in Physics, Phi-
losophy, and Painting: Three Case Studies," in Creativity
and the Imagination, M. Amsler, ed., University of Dela-
ware Press, Newark, DE (1987)
10. Szent-Gyorgyi, A., "In Search of Simplicity and Generaliza-
tions (50 Years Poaching in Science)," in Current Aspects of
Biochemical Energetics, N.O. Kaplan and E.P. Kennedy,
eds., Academic Press, New York, NY (1966) O










Me laboratory


EXPERIMENTS ILLUSTRATING

PHASE PARTITIONING AND

TRANSPORT OF

ENVIRONMENTAL CONTAMINANTS


SUSAN E. POWERS, STEFAN J. GRIMBERG
Clarkson University Potsdam, NY 13699-5710


Historically, chemical engineers have been primarily
concerned with maximizing the efficiency of indi-
vidual processes while designing chemical produc-
tion facilities. Current regulatory pressures to minimize risks
associated with the production of chemicals, however, re-
quire chemical engineers to understand the fate of these
chemicals in the environment. The fundamental mass trans-
fer processes controlling the migration of contaminants in
environmental systems are similar to those in chemical engi-
neering processes. There are distinct differences, though,
that have implications in how individual processes are ana-
lyzed. For example, contaminant concentration in the envi-
ronment is generally very low (on the order of parts per
million (ppm)), and the number of compounds present in a
given environmental system is very large and unknown com-
pared with typically well-controlled chemical engineering
processes. The complexity of these systems needs to be
simplified in order to describe mass transfer process envi-

Susan E. Powers received her BS and MS
degrees in chemical engineering and environ-
mental engineering, respectively, from Clarkson
University. In 1992, following the completion of
her PhD in environmental engineering from the
University of Michigan, she returned to Clarkson,
where she is presently Assistant Professor in
the Department of Civil and Environmental En-
gineering.


Stefan J. Grimberg received a Diplom Engi-
neering (TU) degree in chemical engineering
from the Munich Technical University, and his
MS and PhD degrees in environmental engi-
neering from the University of North Carolina,
Chapel Hill. He presently holds the position of
Assistant Professor in Clarkson's Department
of Civil and Environmental Engineering.


ronmental systems.
At Clarkson University, the fate of hazardous organic
pollutants in the environment is covered in the class "Haz-
ardous Waste Management Engineering." Senior-level stu-
dents from the departments of civil and environmental engi-
neering, chemical engineering, and industrial hygiene typi-
cally enroll in this class. Fundamental processes governing
the environmental fate and transport of organic contami-
nants are covered during introductory lectures and are used
throughout the semester to support more advanced material
related to human exposure levels, risk assessment, and de-
sign of treatment strategies. Throughout the semester, the
relationships between chemical behavior and molecular struc-
ture (i.e., size and polarity) are emphasized.
After this class was taught for two years, it became appar-
ent that students had difficulty grasping the concepts of
partitioning of solutes between phases. Thus, the experi-
ments described here were developed to help students under-
stand the partitioning and transport of organic compounds in
environmental systems. Constraints of class length (50 min-
utes), size (30-40 students per section), and budget, how-
ever, limited the scope of possible experiments. A creative
solution of using nontoxic, colored solutes, allowing strik-
ingly visual detection as the solutes partitioned between
phases, effectively illustrated the concepts of phase par-
titioning and enabled all students to be active partici-
pants in both the qualitative and quantitative components
of this laboratory.

BACKGROUND AND THEORY
A significant fraction of groundwater contamination in the
United States is the result of spills and disposal of organic
liquids in the ground. The organic phases, referred to as non-


Copyright ChE Division ofASEE 1998


Chemical Engineering Education










aqueous phase liquids (NAPLs), are typically consid-
ered to be immisciblee" with water, although their
solubilities are high enough to contaminate groundwa-
ter at levels higher than drinking-water quality stan-
dards."I Figure 1 illustrates the partitioning and trans-
port processes affecting a NAPL such as gasoline.
Since gasoline is less dense than water, it accumu-
lates at the water table. Subsequent partitioning of
contaminants into both the groundwater and soil
gases will occur.
The equilibrium dissolution of solute from a NAPL
and subsequent sorption of the aqueous-phase solute
to sand are considered in this laboratory. Because of
the low concentrations involved in these processes, it
is assumed that the density and molecular weight of
the phases, and activity coefficients of each species in
the aqueous phase, remain essentially constant. For
many NAPLs, it is reasonable to also assume that the
organic phase is an ideal solution and, thus, that activ-
ity coefficients in this phase are close to one. With
these simplifications, phase equilibria governing the
partitioning of solutes between these environmental
compartments is often approximated with linear rela-
tionships describing the concentrations of a species
between phases 21


NAPL-water systems: C = CX (1)
Soil-water systems: q = KdC (2)

where
C concentration (mg/L) of a compound in the aqueous phase
C* solubility of the pure liquid chemical in water (mg/L)
X mole fraction of this compound in the NAPL
q concentration sorbed on the soil (mg/kg)
K soil-water distribution coefficient (L/kg)

Equation (1) is Raoult's Law for liquid-liquid equilibria
and has been shown to be fairly accurate for even com-
plex NAPL mixtures comprised of chemicals with low
solubilities.1 J
Both C* and Kd are partition coefficients describing the
linear equilibrium relationship between phase concentrations.
Their values are highly dependent on the molecular structure
of the compound.131 Nonpolar organic are hydrophobic, ex-
hibiting trends of generally decreasing solubilities and in-
creasing soil-water distribution coefficients with increasing
molecular weight. The presence of polar functional groups,
especially those with O, N, or S atoms, decreases the aque-
ous-phase activity coefficient, thereby greatly increasing the
aqueous-phase solubility and decreasing the soil-water dis-
tribution coefficient of organic compounds.
Following the partitioning of organic compounds from the
NAPL to the aqueous phase, the contaminant molecules are
transported with flowing groundwater, potentially polluting
Winter 1998


Fundamental processes governing the
environmental fate and transport of organic
contaminants are covered during introductory lectures
and are used throughout the semester to support more
advanced material related to human exposure levels,
risk assessment, and design of treatment strategies.


Figure 1. Processes affecting the fate of a NAPL such as gasoline
in the subsurface.


downgradient sources of drinking water. Convection (also
called advection by environmental engineers) and dispersion
are the predominant transport mechanisms, although the sorp-
tion of solutes to soil effectively retards the transport rate.
Assuming equilibrium between solid and the liquid phases,
the standard transport equation with a linear sorption term
added can be written in one dimension as


ac '2C C pb da
dr= D x d
at ax n at


ac D, "2C ux aC
at R Ox2 R ax


where
D, hydrodynamic dispersion coefficient in the longitudinal
direction
ux average linear interstitial velocity of the aqueous phase
R retardation coefficient (R = I + pbKd / n)
n porosity of the porous medium
Pb bulk density of the porous medium
The retardation coefficient can also be described as the ratio
of the mean velocity of water (ux) to the mean velocity of
the solute (uo,)

R = (4)










A solute with a low retardation coefficient (R~-) will be
relatively mobile within an aquifer system, potentially
resulting in higher human exposure levels than a solute
that sorbs strongly.

EXPERIMENTAL DESIGN AND RESULTS
A laboratory experiment was developed to reinforce the
concepts of phase partitioning and its relationship to mo-
lecular structure and the mobility of a solute in a groundwa-
ter system. Three NAPLs with different colors and hydro-
phobicities were mixed with water, and then the contami-
nated water infiltrated through sand to observe the parti-
tioning of the colored solutes. This experiment was in-
cluded in the hazardous waste management class during
the fall semester of 1995.
An assessment of the effectiveness of this laboratory indi-
cated that the students perceived an increase in their compre-
hension of these concepts. Results of their homework as-
signments, however, showed that they still struggled with
quantitative homework problems. Thus, an additional ex-
periment was designed for the 1996 class that involved a
more quantitative measure of retardation coefficients as con-
taminated water samples were pumped through a soil col-
umn and the velocity of the contaminant was measured
relative to the velocity of water.
Materials Adding dye to nontoxic organic phases
created three NAPLs with different colors and a range of
partitioning behaviors. Table 1 describes the composition of
the "red," "blue," and "green" NAPLs. The polarity (or
hydrophobicity) of these dyes is the property critical to their
partitioning behavior and the success of the experiment. The
overall polarity of a molecule depends on contributions of
polar atoms (O, S, N, Cl) and nonpolar atoms (C, H). Quali-
tatively, oil-red-o is more hydrophobic than methylene blue
because a greater fraction of the oil-red-o molecule is com-
prised of carbon (see Table 1). Similarly, green food color is


more polar than methylene blue since the number of polar
atoms in green food color is higher than in methylene blue
(Table 1). In order for the observed partitioning of the color
to be representative of the overall bulk NAPL partitioning,
the polarity of the dye has to mimic the polarity of the
NAPL. The polarity of the bulk organic liquids used in-
creased from mineral oil to ethanol. Thus the polarity of the
selected colors represent the polarity of the NAPL.
Other materials included tap water as the aqueous phase
and clean quartz sand, suitable for a child's sandbox, for
the soil.


Laboratory 1
A Qualitative Understanding of the Partitioning of
Solutes Between NAPL-Water and Water-Sand Systems


The first laboratory allows a qualitative assessment of the


Figure 2. Photograph illustrating the
partitioning of red, blue, and green solutes
(left to right) from a NAPL to water.


TABLE 1
Composition of Colored NAPLs

NAPL Bulk Organic Phase Solute'" Chemical Formula Characteristics

red mineral oil oil-red-o2' C6H24 N40 very hydrophobic
blue 5% (by vol.) octanol in mineral oil methylene blue'31 C,,H,,NSCI slightly hydrophobic
green ethanol green food color4' C6H 007C12 NaS 2151 hydrophilic
C16HONNa2S 261

Only a small amount of dye required for each to provide vivid color
2 Available through Fisher Scientific (biotechnology reagent)
3 Dissolved in octanol prior to mixing with mineral oil
4 Mixture of FD&C Yellow 5 and FD&C Blue 1; available through McCormick & Co. Inc., Maryland
5 FD&C Yellow 5 (5)
6 FD&C Blue 1 (5)

Chemical Engineering Education










partitioning behavior of the red, blue, and green solutes as
well as the bulk organic phases. Teams of 3-4 students each
were provided with bottles containing each of the three
NAPLs, three 40-mL screw-cap vials about 75% full of
water, two filtering crucibles about 50% full of dry sand, two
50-mL beakers, and several disposable capillary pipettes.
In the first phase of the experiment, students observed the
range of possible partitioning behaviors between the NAPLs
and aqueous phase. The steps simply involved adding ap-


TABLE 2
Questions Posed to Increase Conceptual Understanding

Questions for NAPL-water partitioning
Classify the solubility (soluble, partially soluble, insoluble) of
three colored solutes and the bulk organic phases
Discuss the implications of these differences on the fate of
NAPLs in the subsurface
What differences in the chemical structures would you expect
based on the observed solubilities?

Questionsfor aqueous phase-soil partitioning
Rank the solutes in order of increasing potential for sorption;
explain your answer
Discuss the implications of these differences on the mobility
of these solutes in the environment
What differences in the chemical structures would you expect
based on the observed sorption behavior?
Summary questions
Are the observations and conclusions drawn from the
solubility experiment consistent with the results of the
sorption experiment? Explain.
Describe the overall fate of each of the three NAPLs
following a spill to the environment


syringe pump with
100-mL syringes

Figure 3. Schematic of experimental system for column
retardation experiment.
Winter 1998


proximately 1 mL of NAPL to each of the three water vials,
gently shaking them to equilibrate, and then observing the
distribution of color and the bulk organic fluid between
phases. Results range from no observable partitioning of the
hydrophobic red solute in mineral oil to the complete disso-
lution of the very polar green solute in ethanol (see Figure
2). The blue solute illustrates the concept of having a
partially soluble solute in an essentially insoluble bulk
organic phase. In this case, much of the blue color trans-
ferred to the aqueous phase, although most of the volume
of NAPL remained as a separate immiscible phase. This
case is most representative of environmentally signifi-
cant NAPLs such as gasoline.
The second phase of the first laboratory provided a greater
understanding of the partitioning of solutes between aque-
ous and soil phases. As described above, the mixing of
NAPLs and water generated blue and green contaminated
water. Each of these aqueous phases was then poured through
sand in the filtering crucibles that were held over 50-mL
beakers. The very polar green solute was not retarded, as
evidenced by the lack of change in color of either the sand or
water. With the less polar blue solute, however, the sand
turned blue and the effluent became clear, illustrating that
slightly soluble solutes can be strongly sorbed, greatly de-
creasing contaminant concentrations in the aqueous phase.
In order to help students increase their understanding of
partitioning behavior, we posed several questions to pro-
mote their ability to connect experimental observations to
fundamental concepts (see Table 2). These questions fo-
cused primarily on the relationship between chemical struc-
ture and mobility of chemicals in the environment.


The second laboratory was developed to quantify the ex-
tent of solute sorption. The equipment required for this labo-
ratory (see Figure 3) was more extensive and, thus, the
laboratory was conducted as a demonstration, with students
taking turns making the measurements over time. Colored
aqueous phases for this experiment were prepared by the
direct addition of dyes into the aqueous phase (0.05 g/L
methylene blue for the "blue" aqueous phase and 10 mL/L
green food color for the "green" aqueous phase).
Two Plexiglas columns (3.8-cm diameter by 25-cm long)
were carefully packed with a uniform sand (30-40 mesh; d5s
= 0.5 mm) to provide a relatively homogeneous sand to help
minimize solute dispersion within the column. Several pore
volumes of degassed water were then pumped through each
column to displace and dissolve all of the air. At t=0, pump-
ing of the blue and green aqueous phases through the col-










umns at rates typical of groundwater flow (Q=0.1 mL/min)
was initiated.
Using colored solutes allowed visual assessment of the
migration of these solutes. The interface between clean and
colored water was marked on each column over time and the
average distance traveled by the colored water was recorded.
Assuming that convection is the predominant transport
mechanism, the position of the sharp front marked by the
colored water was used to estimate the interstitial solute
velocity. Thus, the retardation coefficient (Eq. 4) was calcu-
lated as

R =QA (5)
L/t
where
Q volumetric flow rate of water
A column cross-sectional area
L distance traveled by the colored water in time t
n porosity, included to convert to an interstitial aqueous
phase velocity

Equation (5) can be rearranged to calculate the retardation
coefficient by linear regression of the L-versus-t data.
Figure 4 illustrates differences in the travel time of the
solutes through the soil columns. As expected from the
qualitative experiment described above, the greater distance
traveled by the very-polar green solute indicates that it is
much more mobile than the less-polar blue solute. The ob-
served variability in the position of the front around the
column perimeter at any point in time (Figure 4) is attributed
to column-scale heterogeneities in soil permeability that af-
fect local rates of convection. To accommodate for this
variability, the experimental analysis was completed using
the average of four measured travel distances at each time.
These average travel distances with error bars representing
one standard deviation are included in Figure 5.
Linear regression of the data was used to estimate the
retardation coefficients for each solute. Regression coeffi-
cients greater than 0.99 were obtained in both cases. The low
retardation of the green solute (R= 1.40.1) confirms the fact
that this solute would be highly mobile in an aquifer system,
while the higher retardation coefficient for the blue solute
(R=4.4+0.2) provides quantitative evidence of the greater
extent of sorption of this solute. With both visual and quanti-
tative interpretation of this experiment, students grasped the
impact of sorption and the connection between this partition-
ing process and the potential for exposure to contaminants
through drinking water downgradient of a pollution source.

DISCUSSION AND CONCLUSIONS
Students completing these experiments observed the wide
variability in the behavior of organic pollutants in the envi-
ronment. They concluded that the mobile green solute and
the bulk organic liquid that comprised this NAPL were hy-


Figure 4. Photograph of the column retardation experi-
ment after twelve hours. The polar green solute clearly
travels at a higher velocity than the blue.


0 500 1000 1500 2000
Time [min]
Figure 5. Calculation of retardation coefficients from mea-
sured average distance of solute travel as a function of
time. Solid lines represent the linear regressions and error
bars illustrate one standard deviation of the four indi-
vidual measurements of distance at each time.
Chemical Engineering Education










drophilic and very mobile in the environment. The solute
and bulk organic liquid that comprised the red NAPL, on the
other hand, were very hydrophobic and relatively immobile
in an aquifer system.
From a pedagogical standpoint, providing students with an
active learning experience and very visual observation of
these phenomena effectively improved their overall under-
standing of the fate and transport of organic contaminants in
an environmental system. In terms of Bloom's hierarchy of
learning,'4' the first laboratory increased the students' com-
prehension, while the second laboratory addressed the appli-
cation of these ideas in engineering calculations. Both com-
prehension and application are critical steps for the students
to achieve prior to advancing to the more challenging tasks
of analysis and synthesis. Thus, by completing these labora-
tories early in the semester, students were better prepared for
tackling more complex issues associated with formulating
engineering decisions with respect to the potential for envi-
ronmental contamination.

ACKNOWLEDGMENTS
Support from a National Science Foundation CAREER grant
(BES-9501567) was used in developing these laboratories.

REFERENCES
1. Cohen, R.M., J.W. Mercer, and J. Matthews, DNAPL Site
Evaluation, C.L. Smoley, Boca Raton, FL (1993)
2. Thibodeaux, L.J., Environmental Chemodynamics: Move-
ment of Chemicals in Air, Water, and Soil, 2nd ed., John
Wiley and Sons, New York, NY (1996)
3. Verschueren, K., Handbook of Environmental Data on Or-
ganic Chemicals, 2nd ed., Van Nostrand Reinhold, New
York, NY (1983)
4. Wankat, P.C., and F.S. Oreovicz, Teaching Engineering,
McGraw-Hill, New York, NY (1993)
5. Colour Index, 3rd ed., The Society of Dyers and Colourists,
Bradford, England (1971) O




COMET Project
Continued from page 23.
for introducing these topics.
As the instructor, I should have made more clear to the
students the connections between the project and the course
material. I also should have explained why the project is of
value to a beginning engineer. Clearly stated instructional
objectives are known to facilitate student learning.'"" The
project might have been more closely linked to the main
course content if, for example, it had permitted chemical
energy sources and involved more energy balance calcula-
tions in the COMET design. But this would have been diffi-
cult since the project had to be safe and relatively short and
simple for sophomore students. The COMET project is there-
fore a compromise that achieves the primary goal of intro-
Winter 1998


during ideas not found in traditional pencil-and-paper
projects, but does so in a non-chemical engineering-specific
format.
Logistical Improvements
"I think this project would have been better at the beginning
of the quarter."
"Give the groups an extra week or so to think about the
project."
"Make the project worth more than 5%."
A number of students would have preferred different lo-
gistical arrangements for the project. Because it involved a
lot of work, students wanted the project assigned earlier in
the quarter when it would not conflict with midterms, wanted
more time to work on the project, and wanted it to be worth a
larger fraction of their grade. All of these changes can be
easily made and will be implemented next time.

CONCLUSIONS
The COMET project provided a relatively simple assign-
ment that introduced sophomore chemical engineers to a
number of important engineering concepts that are often not
addressed until later in the curriculum: teamwork, open-
ended problems, design, hands-on experimentation, techni-
cal writing, and estimation based on limited data. Most stu-
dents enjoyed the project and recommended its use in future
classes.

ACKNOWLEDGMENTS
Thanks to Melissa Bradley, Richard Felder, and David
McGill for helpful discussions and to Dayton Funk for pho-
tography. This work was supported in part by a CAREER
Young Investigator Award from the National Science Foun-
dation (BES-9624832).

REFERENCES
1. West, W., W. Flowers, and D. Gilmore, "Hands-On Design
in Engineering Education: Learning by Doing What?" Eng.
Ed., 80, 560 (1990)
2. McConica, C., "Freshman Design Course for Chemical Engi-
neers," Chem. Eng. Ed., 30, 76 (1996)
3. Davies, W.A., "Design Competition for Second-Year Stu-
dents," Chem. Eng. Ed., 30, 102 (1996)
4. Felder, R.M., and R.W. Rousseau, Elementary Principles of
Chemical Processes, 2nd ed., John Wiley & Sons, New York,
NY (1986)
5. Angelo, T.P., and K.P. Cross, Classroom Assessment Tech-
niques: A Handbook for College Teachers, 2nd ed., Jossey-
Bass, San Francisco, CA (1993)
6. Bell, J.T., "Anonymous Quizzes," Chem. Eng. Ed., 31, 56
(1997)
7. Schmeck, R.R., ed., Learning Strategies and Learning Styles,
Plenum Press, New York, NY (1988)
8. Felder, R., "Meet Your Students: 3. Michelle, Rob, and Art,"
Chem. Eng. Ed., 24, 130 (1990)
9. Felder, R., "Matters of Style," ASEE Prism, 6, 18 (1996)
10. Mager, R.F., Preparing Instructional Objectives, 2nd ed.,
Lake Management and Training, Belmont, CA (1984) J











Random Thoughts...







SHIPS PASSING IN THE NIGHT



RICHARD M. FIELDER
North Carolina State University Raleigh, NC 27695-7905


Ever get a sneaking suspicion that our students may not be
totally focused on the intellectual delights of thermodynam-
ics and transport phenomena while we're lecturing? It some-
times happens that other things are on their minds, especially
when we're enthusiastically filling the board with letters,
numbers, and squiggles that have no apparent connection to
anything they know or care about. For example,


Professor Cheever:
". .. and next we'll examine laminar flow of a
newtonian fluid in a circular pipe and derive Equa-
tion 4.5-35 in your text. We first draw this differen-
tial element and now we itemize the stresses
acting on it, starting with .."



Student A (SA): "Hey Jerry, how's the rest of your
schedule look?"
SB: "Not bad-I've got a couple of humanities courses so I
shouldn't be overworked."
SA: "Unless you get old Ferguson .. last spring she gave
us five books to read in the first week, including Moby
Dick. It's about a fish."
SC: "What did he say that arrow pointing up is?"


Richard M. Felder is Hoechst Celanese Pro-
fessor of Chemical Engineering at North Caro-
lina State University. He received his BChE from
City College of CUNY and his PhD from
Princeton. He has presented courses on chemi-
cal engineering principles, reactor design, pro-
cess optimization, and effective teaching to vari-
ous American and foreign industries and institu-
tions. He is coauthor of the text Elementary
Principles of Chemical Processes (Wiley, 1986).

@ Copyright ChE Division ofASEE 1998


SD: "Who knows? ... Ijust wonder how I'm going to make
it to December if I'm this lost now."
SC: "You and everybody else ... except maybe old Arthur
here ... Hey Art-you getting this?"
SE: "No, but I've seen his old tests-you don't need to
understand anything, you just need to plug into
formulas.
SD: "Cool!"


Professor Cheever:
"... and as we know from calculus, the limit of this
expression as delta r approaches zero is what? ...
anyone remember? ... no? ... well, it's the partial
derivative, and so we can replace..."



SF: "What say, Chief-coming to the Delta Chi mixer
tonight?"
SG: "No can do-I got a physics test tomorrow and if I
don't get my grades up I can kiss my scholarship
goodbye."
SF: "Aw, come on, Sir Isaac-you know that stuff A couple
of brews and you'll be relaxed and ready to hit that
test like a sledgehammer."
SG: "That's what you said before the chemistry final last
spring and if I remember right you relaxed your butt
into a D.
SF: "Yeah, but that final was..."
SH: "So how'd it go last night?"
SI: "Don't ask ... that geek Rachel set me up with is
majoring in soil science or something and he spent the
whole night talking about fertilizer. Let me tell you a


Chemical Engineering Education










few things about phosphorus that you probably
never. ..


Professor Cheever:
"Now at this point we introduce the stress tensor, a
convenient and concise representation of the nor-
mal and shear stresses in the..."




SJ: "Yo, Sally-hand me some of them chips there."
SK: ". Problem 3 on the thermo homework?"
SL: "Yeah, it's a killer, but it's cute-you have to figure
out the equilibrium partial pressure of nitrous oxide to
know if the dental hygienist poisoned the bank presi-
dent."
SK: "Right, Ifigured that much out, but at that pressure
you can't just plug into Raoult's law and I don't how
how you.. ."
SJ: "Yo, Gene, can I have a hit of your Dr. Pepper?"
SM: "What time you got-I think this has been going on for
about four hours but I'm not sure."
SA: "Twenty minutes to go and counting."


SA: "Ten minutes.
SN: "Shh-don't wake Brenda ... she's the only one
getting anything useful out of this class."
SO: "It's my grandmother this time-I'll probably have to
go home for the weekend again and just hope I can
find some time to look over the..."
SJ: "Yo, Bruce, hand me a couple of them Cheez Doodles,
would ya?"
SQ: "Hear about Monica, Sheila's roommate?"
SR: "No, what about her?"
SQ: "She's been acting weird lately, just lying in her room
staring at the ceiling for hours."
SR: "Sounds bad."
SQ: "Gets worse-someone found her passed out next to
an empty pill bottle yesterday. Sheila saw her at the
hospital today and thinks she'll be all right but she still
looks kind of green."
SR: "Bummer! That's like what happened to Rudy last
year, only instead of popping pills he ..."


SA: "One minute."
ST: ". ok, now here in Problem 4 what I think we need to
do is..."
SU: ". so the horse says to the chicken ..."
SJ: "Yo, Angie, lemme have a couple of those M&M's-I
like the orange ones."
SV: ". .. and at least we got to do something in those class
exercises Furze was always giving in mechanics-you
make me sit for an hour without doing anything and
i'm ."
SG: ". no, we're going down to the beach Friday right
after class-tell Jack and Ella we'll meet Monday
afternoon in the lounge and finish that report, and then
we can ...
SE: ". but that correlation only works at low concentra-
tions. Maybe if we..."
SW (laughing): "That's a good one ... did you hear the
one about the rabbi, the priest, and the chemical
engineering professor who were on a ..."
SX: ". .. and he's really mad and told Mom that he's not
going to pay my tuition any more so I may have to find
a job, and I don't think I can stay in school and work
enough hours to ..."
SY: "Hey, Cindy-how about asking him if we're respon-
sible for this stuff on the exam. I love the faces they
make when you ask them that."
SA: ". .. and there's the buzzer, and I'm out of here."
SZ: "Yo, Vinnie, bring your book to the Keg tonight-I got
afew questions about Eq. 4.5-237. "
SJ: "Hey, no problem-that one's my favorite. Come on-
let's grab a burger and fries across the street before
we go to the..."




Professor Cheever:
". and now if you substitute this expression for
the friction term you end with Equation 4.5-35.
Everybody understand? Good, see you Friday."




SA: "And the point of all that is?"
SZ: "Beats me." C


All of the Random Thoughts columns are now available on the World Wide Web at
http://www2.ncsu.edu/effective_teaching/ and at http://che.ufl.edu/-cee/


Winter 1998


47










5j9 learning in industry


This column provides examples of cases in which students have gained knowledge, insight, and
experience in the practice of chemical engineering while in an industrial setting. Summer interns and
co-op assignments typify such experiences; however, reports of more unusual cases are also wel-
come. Description of analytical tools used and the skills developed during the project should be
emphasized. These examples should stimulate innovative approaches to bring real world tools and
experiences back to campus for integration into the curriculum. Please submit manuscripts to
Professor W. J. Koros, Chemical Engineering Department, University of Texas, Austin, Texas 78712.





MAKE SUMMER INTERNSHIP A

LEARNING EXPERIENCE


GARY S. HUVARD
12218 Prince Philip Lane Chesterfield, Virginia 23838


any engineering undergraduates have the oppor-
tunity to work on one or more summer internships
before they graduate. In principle, the students are
paid to spend the summer learning how engineering projects
are carried out in the real world.
Time out for a reality check. Without significant planning
by faculty, the chances of an undergraduate summer intern
actually learning something useful are not very good. Unlike
graduate students, who usually receive projects consistent
with their research expertise, undergraduates are often sim-
ply parceled out to various plants or R&D facilities. Rarely
are faculty members involved in site or project choices; no
one really knows what the students will end up doing, and
there is rarely any follow-up to find out if they learned
anything of substance.
Let's review how this process often works. Sometime
around March or April, someone on the faculty starts phon-

Gary S. Huvard earned a BS in Chemistry from
Campbell College (1974) and a PhD in Chemi-
cal Engineering from North Carolina State Uni-
versity (1978). He spent eight years with the
Corporate Research Group at BFGoodrich
(Brecksville, Ohio) and three years with du Pont's
Tyvek Technical organization (Richmond, Vir-
ginia) before establishing a private practice in
1989. Since that time, he has worked with more
than 20 different companies on projects span-
ning the breadth of ChE practice.


ing industrial contacts-usually research directors or plant
managers-with questions like "How many kids can you
take this year?" "Can't you squeeze just one more slot out of
the budget?" The director comes up with a number and the
faculty advisor jots it down and continues to make calls until
the available slots match the number of students wanting
internships that summer.
On the industry side, a hand-off then takes place. The
logistics of getting the students in, getting non-disclosure
agreements signed, arranging something with Accounting
and so forth is passed to the Human Resources Depart-
ment. Around the first or second week of May, the HRD
calls the director (or whoever) to inform him or her that
everything is set and that 2 (or 4 or whatever) students
will be arriving on June 5.
Now the real planning starts. The director immediately
begins scanning a list of technical persons, identifying likely
candidates to supervise a summer intern. The scientists cho-
sen are requested to submit, by Friday at the latest, a descrip-
tion of The Project.
On Wednesday afternoon, the about-to-be intern supervi-
sors earnestly look for a gas chromatograph and a discarded
286. Being experienced industrial scientists, they are well
aware that any engineering student can be safely and harm-
lessly occupied for at least three months so long as The
Project entails one of two activities:


Copyright ChE Division ofASEE 1998


Chemical Engineering Education









Project #1, Description
Optimum functionality of our proprietary
XLR34 Recombinant Distillation Process
requires a complete understanding of the
quaternary splits of all components
throughout the column internals. The
summer intern will be used, as suggested
by our Total Quality Management Life
Cycle Engineering guidelines, as a
resource to speed up the analysis of tray-
to-tray hydrodynamics in the XLR34
downcomers. The data will be used to
build a simulation (see The Project #2) of
downcomer flow stability needed for
optimum economic ROI.
Translation
I'm going to have the kid stand in front of
that old GC for three months injecting
samples and recording peak areas. Aside
from stabbing himself with the needle, there
is virtually no way the student can get hurt
and I'll never have to deal with the safety
people or do any of their paperwork. Plus,
he'll have an enormous pile of numbers to
plot and try to make sense of which will
keep him out of my hair for three months
and give him at least six overheads to present
in the project review in August.


Project #2 Description
The Economic Viability Indices for our
proprietary XLR34 Recombinant Distilla-
tion Process are very dependent on
downcomer hydrodynamic functionality. In
order to maximize the R&D Investment
Index, as suggested by our Total Quality
Management Life Cycle Engineering
guidelines, it is critical that fluid dynamic
computations be carried out to model the
flow striations previously described in our
Project Monthly dated 2/9. A suitable
computer system has been procured for use
by the summer intern. Our goal will be to
develop a proprietary computer simulation
to describe these striations. Infuture
communications, this program will be
code-named Program XLRC to minimize
the potential that in-kind competitors
recognize our activities.
Translation
We found an old 286 that nobody was


using and set it up in the corner of the
high bay. Since any program has to be
written in QuickBasic to run on this
thing, it should take at least three months
to get ain driiI, working. Aside from eye
strain, there is virtually no way the
student can get hurt and I'll never have
to deal with the safety people or do any
of their paperwork. Plus, there will be an
enormous pile of code to write and try to
debug, which will keep this person out of
my hair for three months and give him or
her at least 6 overheads to present in The
Project Review in August. Best of all, by
September 10, nobody on earth will
remember what XLRC means, and I
can bury the whole business and get on
with my life.


The Research Director, having received the
project descriptions in a timely manner, passes
them on to the faculty advisor. The advisor is
quite pleased. These students will really learn
something this summer! (Not!)
We have just described two very successful
summer internships. I have personally witnessed
dozens of them. From the standpoint of the
Research Director and the company, the stu-
dents came in, worked on something presum-
ably useful to the company, and left without
having been physically altered. Too bad no one
thinks to ask the intern whether he or she actu-
ally learned anything useful.
To be fair, we should point out that many
companies make an admirable effort to identify
appropriate intern projects. In these companies,
project ideas are solicited and reviewed by staff
engineers (possibly a special committee) prior
to intern assignments. Rarely, however, do pro-
fessors take part in these reviews. While many
companies conduct on-campus interviews for
summer interns, the results may be undesirable
since the professors, again, are left out of the
planning process.
Unfortunately, few practicing engineers are
able to assess whether a given project is appro-
priate for an undergraduate chemical engineer-
ing student. To test this, just ask a few indus-
trial colleagues to submit problems for the
sophomore mass and energy balance course.
Don't be surprised if many of the problems are
far too difficult for students at this level. We


Without
significant
planning by
faculty, the
chances
of an
undergraduate
summer
intern
actually
learning
something
useful are
not very
good. Rarely

are faculty
members
involved in
site or project
choices;
no one
really knows
what the
students will
end up
doing, and
there is
rarely any
follow-up
to find out
if they
learned

anything of
substance.


Winter 1998









easily forget how hard those problems once seemed.

A BETTER WAY
Setting up meaningful summer internships for your stu-
dents is possible. But, it takes commitment by the entire
department and continue ing effort. If you really want your
students to learn something useful, try following the route
outlined below.

Establish Contacts with Engineers,
NOT with Managers
It must be very tempting, given everything else you have
to do, to simply place that once-a-year call to the R&D
Director. Unfortunately, many R&D Directors I have known
don't have a clue on how to define a good internship prob-
lem. But if you make the effort to befriend the engineers who
actually do the technical work, you can make dramatic
progress toward the goal of finding truly excellent summer
intern problems. The hard part is finding the right engineers.
In addition to using whatever contacts you already have
(alumni are excellent contacts), try scanning the programs
from recent AIChE meetings for industrial participants
who either wrote or co-wrote papers. Chances are good
that a phone call and short pitch to these contacts will
unearth a number of people interested in working with
someone from the university.
Generally, engineers will not have the authority to grant
internship funding. If their company is not in the habit of
hiring summer interns, you may need to help the engineer
outline for management the economics of sponsoring one or
two interns. To do this, e-mail or fax the engineer a single
page showing the approximate cost for having a student on-
site for three months. It should include student salary, travel
reimbursement, and housing if appropriate.

0 Sell the Program
Once you have a commitment from the engineer, get the
name and telephone number of the appropriate manager and
place a call to that person. Be prepared to wait one to three
months (or more) for management approval; virtually noth-
ing is done in industry without having one or two meetings.
Expect the manager to say something like, "Let me get
together with Bob and some of the other engineers to discuss
this first, and I'll get back to you later." Always get a firm
date and time when the manager will "get back to you." If
they don't contact you within a reasonable amount of time,
and often they won't, get back to them. A certain amount of
nagging can be productive.
Managers like to perceive benefits, tangible and intan-
gible, for any and all money they spend. And, you are asking
them to spend money on something they haven't been con-
vinced they need or want. To this end, have a list of potential


benefits handy. Mention such things as
Increased productivity without a fixed cost on the
balance sheet.
Students are well trained and might bring in new
ideas and techniques.
Students often accept positions after graduation with
their internship sponsors. This can help hold down
recruiting costs.
Publications that result from internships reflect well
on the sponsoring company and its management.
The sponsoring engineer will have better access to the
university and any technical or recruiting help the
faculty might provide in the future.
If it sounds like I'm telling you to "sell" internships, I've
made my point. That is precisely what you are doing and
exactly how you should approach the activity. It need not be
a hard sell; the best sponsors, long-term, will be those who
buy enthusiastically after a soft pitch. All you want is a
commitment and a letter from that manager supporting the
internships. Once you have this commitment in writing,
whether obtained through the engineer or by directly ap-
proaching management, you are in a position to start defin-
ing the problems.

Defining the Internship Problems
You will always know far more than your engineer-spon-
sor about the capabilities of the students and the types of
problems that would be suitable for them. But, the engineer-
sponsor knows far more about his or her process than you
know and, therefore, presumably knows what the problems
are. So, in this phase, you should have two goals:
1) Learn about the process so you can help define
appropriate problems.
2) Teach the engineer-sponsor what he or she needs
to know to suggest appropriate problems.

The first goal above should be a short-term activity. If
possible, visit the plant or R&D center to learn about the
process yourself; do not assume that the engineer-sponsor
fully understands the process. Chances are there are many
aspects of the process that are not considered "problems"
simply because they aren't presently troublesome. I have
never encountered a process that couldn't be improved in
dozens of ways if someone simply paid some attention to the
aspects that weren't "problems." Many such improvements
could result from a three-month internship study. Since the
cost of the internship is relatively low and the return on such
improvements is usually rapid and measurable, it is easy for
the company to justify the work. But, someone has to clearly
point out potential improvements or they will continue to go
unnoticed.


Chemical Engineering Education









The second goal (training engineers to define good in-
ternship projects) is a long-term investment in your pro-
gram. After expending considerable time and energy to de-
velop sponsors, you would like to retain them for many
years and, as quickly as possible, reach a point where the
engineer-sponsors can suggest suitable problems without
your assistance.
Good internship problems have certain distinguishing at-
tributes:

LI The problem can be approached by a junior or senior
chemical engineering student and solved (or good progress
can be made) using skills that students at that level can be
expected to have or to easily acquire. The analysis or design
of a single unit operation is usually appropriate. As an ex-
ample, suppose a plant has a rotary dryer that uses preheated
air for drying, but there is no recycle of the exhaust. How
much money could be saved by recycling some of the hot
exhaust air? Would the product quality be the same if the
dryer is operated at a higher humidity? Would productivity
suffer? How much capital investment would be required?
Should this change be made? Even though the dryer perfor-
mance is currently "acceptable," the operation might be
wasting a substantial amount of energy. An analysis of this
dryer would make a great three-month intern problem. The
solution requires mass and energy balances, understanding
relative humidity and psychrometric charts, basic equipment
cost estimation, and basic economic-return calculations. Some
experimentation might also be needed, but chances are, old
company reports will have drying curves for the product at
different conditions of temperature and humidity. The stu-
dent will then also get some practice in doing an internal
literature search.

E[ The problem can be completed (or really good progress
can be made) during the time allotted to the internship.
Don't minimize the importance of this attribute. Students
quickly become demoralized if they begin a project and then
discover they cannot possibly complete it. They find it em-
barrassing and often discouraging to have to give the cus-
tomary end-of-internship talk to the technical staff on a half-
completed project. For example, an analysis of the entire
heat exchanger network in a large plant cannot be carried out
by anyone in three months, but an intern could analyze the
performance of one small network of heat exchangers (three
or four) in that time.

E The sponsor should have already obtained any needed
data that cannot be collected in the first month of the study.
For example, the analysis of a batch polymerization reactor
might sound like a good project, but chances are that the
sponsor does not have the necessary kinetic data for the
analysis. (If the data existed, someone would have already
done the reactor analysis.) If you assign this problem with-


out reviewing the available data, you may doom the student
to a miserable summer. The intern may spend the entire
summer waiting for analytical equipment to be delivered or,
worse, spend the summer trying to get an ancient GC work-
ing that never will.

E The project should test and stretch the student's engi-
neering skills. Does the project require mass and energy
balances to be written and solved? Is statistical analysis of
data required? Does the project require the student to learn
some new chemistry? Are periodic written progress reports
required? Is a literature search needed? Beware of project
ideas that begin with "We could sure use some help getting
the data we need on Project GruntWork...."-it is a sure bet
that your student will spend three months standing in front of
some infernal apparatus testing one sample after another.
The intern learns NOTHING from this type of activity. If a
company just wants some data taken, it should hire a temp.
You can do better for your students.

El The intern should be safe while working on the project.
Most engineer-sponsors will go to heroic lengths to guaran-
tee the safety of their interns. Nevertheless, you should, if at
all possible, look over the sponsor's shoulder on this issue.
Ideally, your program teaches industrial safety as an integral
part of the chemical engineering curriculum and your stu-
dents are capable of auditing their own work environments.
Give your students practice before turning them out by as-
signing safety audits as part of your unit operations and
design courses.

Complete the Cycle
Defining appropriate projects will be far more time-con-
suming than arranging internships. Clearly, one or two fac-
ulty members cannot do all the work. One good way to
spread the work load is to get the students involved. Once
given a set of guidelines like the ones above, there is no
reason that small teams of students (three or four to a team)
can't work with engineer-sponsors to draft lists of potential
projects. If possible, involve yourself in the review process.
By observing the ability of your students to assess the project
ideas, you will quickly find out whether they have learned
the material you've been teaching.
In this way, you can help each class identify new projects
and problems for the classes to follow. In addition to learn-
ing to identify those "hidden" process improvements de-
scribed above, your students will be learning teamwork,
proposal preparation, communication skills, salesmanship,
and, hopefully, a bit about obligations to future generations.

ACKNOWLEDGMENTS

The author would like to thank Prof. R.M. Felder for his
helpful revisions and editorial contributions. 1


Winter 1998










r curriculum


AN INTRODUCTORY ChE COURSE


FOR FIRST-YEAR STUDENTS


KENNETH A. SOLEN, JOHN N. HARB
Brigham Young University Provo, UT 84602


Freshman students who have an interest in chemical
engineering have several important needs that we feel
should be addressed. First, many of them are still
undecided about their major and need help making that
decision. Second, these students need to receive instruction
that provides a broad, integrated perspective to serve as a
foundation for subsequent classes. Finally, first-year stu-
dents need to experience support and encouragement from
faculty and other students.
In spite of these needs, chemical engineering departments
traditionally have done relatively little for these students,
often relegating them to a generic computing class or to a
generic freshman engineering class. For example, for many
years at BYU, the only "chemical engineering" courses taken
by first-year students were a course in FORTRAN program-
ming and a 0.5 credit freshman seminar. But we have re-
cently changed our curriculum to better meet the needs of
these students; among those changes has been the development
of a new introductory course-the subject of this paper.

GOALS FOR THE COURSE
We began development of a course for first-year students
with several distinct goals in mind (summarized in Table 1),
with the most important of those goals being
1. To provide knowledge about the chemical engineering
field to help students select their major.
2. To provide an integrativefoundationforfuture courses.
We wanted to provide sufficient information about the
discipline to enable students to make an educated decision
regarding their choice of a major. To meet this goal, we felt
it was important for the students to experience chemical
engineering reasoning, calculations, decisions, and applica-
tions. These experiences should include an introduction to
some of the fundamental principles and equations (e.g., Fick's
Law, Fourier's Law, etc.). To increase learning and interest,
we also wanted to help students understand the impact of
chemical processing on their own lives and to understand the
connection between chemical engineering and their "every-


day" experiences. We felt that it was important for the stu-
dents to evaluate and draw conclusions from numerical re-
sults as would be typically done by a chemical engineer.
Further, we wanted to expose students to "design" problems
that were open-ended and had multiple solutions.
Finally, we wanted the material to challenge the students
in order to stimulate their interest and to provide them with a
sense of the curriculum's rigor. This last goal was motivated
in part by our prior experiences with survey courses that
failed because they did not offer much intellectually to the
students entering our department; students felt that such
courses were neither challenging nor informative and were
essentially a waste of their time.
We wanted this course to play a significant role as part of
our undergraduate curriculum by providing a foundation and
perspective for subsequent classes. It has been our observa-
tion that sophomores, juniors, and even seniors sometimes
view each course in their program as an isolated entity,
unrelated to the other subjects they have studied. Instead of
building on past learning, they often seem to start over with
each new subject. Hence, they frequently fail to see the
discipline as a whole until very late in their program (if at
all). Therefore, a key objective of our course was to provide

Ken Solen is Professor and Department Chair of
Chemical Engineering at Brigham Young Univer-
sity. He received his BS in Chemical Engineering
(1968) from the University of California at Berke-
ley and his MS in Physiology (1972) and his PhD
in Chemical Engineering (1974) from the Univer-
sity of Wisconsin. He conducts research in bio-
medical engineering and artificial organs.


John Harb is Associate Professor of Chemical
Engineering at Brigham Young University. He re-
ceived his BS (1983) from Brigham Young Uni-
versity and his MS (1985) and PhD (1988) from
the University of Illinois, Urbana, all in chemical
engineering. His research interests include elec-
trochemical engineering and mathematical mod-
eling of complex physical systems.
Copyright ChE Division ofASEE 1998
Chemical Engineering Education










an integrated overview, offering a broad perspective and
serving as a framework upon which subsequent courses could
be built. That objective included helping the student under-
stand where subsequent chemical engineering courses fit
within the larger perspective as well as how knowledge
obtained from other disciplines (e.g., chemistry, math, phys-
ics, economics, etc.) is essential. In a figurative sense, the
introductory course would create a "skeleton" by broad shal-
low coverage of the discipline, and later courses would add
the "meat" to that skeleton.
Additional goals were related to the social needs of the
students. It is our opinion that first-year students should have
close interaction with the faculty. While some interaction is
facilitated by faculty-student socials, required meetings with
advisors, etc., our course provides many more faculty-stu-
dent contact hours than any other method. Of equal impor-
tance to faculty-student interactions are interactions between
the students themselves. One of our goals for the introductory
course was to help develop a "community of chemical engi-
neers" through the use of learning teams and group activities.


of the potential advantages that it would offer our students,
provided that the course was designed to minimize the re-
source requirements associated with it. Consequently, the
course was designed as a two-credit-hour one-semester course
without a laboratory (even though we recognized the value
of a laboratory experience for our beginning students). Two
credits were made available for the course as part of a
general restructuring of the curriculum, and the necessary
resources were allotted for development of the course.

THE COURSE
The goals listed in Table 1 had a significant impact on the
course's structure during its development. In particular, our
desire to provide an integrated overview required that the
individual course topics be connected together in a logical
fashion. This integration was accomplished by structuring
the course around an engineering design problem that could
be solved by designing a simple chemical process. The en-
tire semester and all the material presented in the course
were dedicated to the design of that process.


CONCERNS
There were several concerns that in-
fluenced development of the course and
led us to minimize the credit hours and
faculty resources associated with it. It
was clear that a new course could not
simply be added to a curriculum that
was already overflowing, especially at a
time when we were being encouraged to
decrease the number of credit hours in
order to help students graduate more
quickly. Thus, inserting this course meant
reducing the credit hours of more ad-
vanced courses, and some faculty ques-
tioned the value of such a trade. Also,
since a large number of beginning stu-
dents do not continue in the discipline
after their first year, there was concern
that an introductory course would dedi-
cate resources to teaching
students who would not
graduate in chemical engi- Ce
neering. Further, the course Prob
we envisioned would need Chemical
to be developed from processes
scratch since a suitable text Ino
was not available, thus add- p"
ing to the required re-
sources.
After some discussion,
the department decided to
support the course because Figure 1.
Wea
Winter 1998


TABLE 1
Goals for an Introductory Course in ChE
1. To provide information about the chemical en-
gineering field and thus enable students to knowl-
edgeably select their major.
2. To provide an integrated overview of chemical
engineering as a foundation for subsequent
courses.
3. To teach significant chemical engineering prin-
ciples, including
Fundamental concepts and quantitative rela-
tionships
Connections to the students' past experiences
Typical chemical engineering calculations and
analyses
Open-ended, multi-solution design problems.
4. To promote interaction between first-year stu-
dents and the chemical engineering faculty.
5. To help develop a "community of chemical en-
gineers."



ign,
lem
Matenal Mateals
Balance Flud Reacton
Mechanic Engineern Energy
Units./ Balance
Process Spreadsheets. Mass Hea Proc
vanrablhe e Graphing Caont

ACID-NEUTRALIZATION DESIGN PROBLEM
C

Schematic of the topics covered, where the
ch bar represents the time spent on the topi


The problem-oriented scenario begins
the first day of class when the students
are asked to imagine that they "are
chemical engineers working for the ABC
Chemical Company." The student engi-
neer receives a memo from his/her su-
pervisor reporting that the contractor
who has been disposing of the hydro-
chloric acid by-product from "our"
manufacturing process is going out of
business. The memo goes on to ask the
student to take responsibility for solving
this problem, and the remainder of the
course is directed toward leading the
student to that solution. This design prob-
lem provides the framework for integra-
tion of material presented throughout the
semester.
The general topics presented in the
course are shown in Figure 1, with the
approximate amount of time
dedicated to each topic in-
dicated by the length of the
segment to which the topic
title is attached. This two-
Eonormics credit course is designed to
s be taught in fourteen weeks,
the length of a semester at
BYU. Written material de-
veloped for each of the top-
.SES v cs has recently been com-
bined into a textbook,1" with
length of each topic forming a sepa-
c.










rate chapter. The table of contents of the textbook, shown in
Table 2, reflects the detail and sequence of topics treated in
the course.
The topics are introduced on a "just-in-time" basis as the
solution to the design problem is developed throughout the
semester. For example, after discussing strategies for gener-
ating and evaluating possible solutions, the decision is made
to design a chemical process in which sodium hydroxide is
used to neutralize the HCI. Material balances are then taught
in order to determine how much NaOH is needed. Spread-
sheets are also introduced as an engineering tool. The stu-
dents are then taught simple fluid mechanics to provide the
basis for delivery of the NaOH and HCI from the storage
facilities to the point of reaction. This approach continues as
issues are considered regarding mixing the acid and base
(mass transfer is taught), the volume of reactor needed (reac-
tion engineering is introduced), and cooling the final product
to an acceptable temperature for disposal (energy balances
and heat transfer are studied). The final step is an evaluation
of the profitability of the proposed process (economics are
introduced).
By the end of the semester, students have developed skills
in several of the subdisciplines that make up chemical engi-
neering and have applied them toward the solution of an
engineering design problem. These skills represent a useful
subset of those that they will learn in subsequent chemical
engineering courses. In order to illustrate the level at which
the material is presented, Tables 3 and 4 provide examples
of problems used in the course along with the appropriate
solutions as presented in the textbook.
Process flow diagrams are used throughout the course to
help the students visualize how the different aspects of the
course and design problem are connected. Students are in-
troduced to these diagrams and required to use them very
early in the semester (Chapter 2). Then, as each new topic is
introduced and used to design an additional component of
the "process," the process flow diagram and stream table are
updated to reflect the new addition and its relationship to the
previous components of the process.
In contrast to the acid-neutralization design problem, the
solution for which is developed for the students throughout
the semester, the course also features a second design prob-
lem, or case study, to be solved independently by student
teams. The case study, described in the last chapter of the
book, involves the isomerization of meta-xylene to ortho-
xylene and requires the use of material and energy balances,
the sizing of a pump, reactor, and some heat exchangers, the
preparation of a process flow diagram, and the completion of
an elementary economic analysis. It is introduced near the
end of the semester and provides the students with an oppor-
tunity to work together, to learn from each other, and to
apply nearly all of the concepts and principles they have
learned throughout the semester. Although new material is


presented in class during the time that students are working
on the case-study assignment, the last few topics (particu-
larly engineering materials and process control) are treated
qualitatively and briefly, with minimal homework assign-
ments, to give the students time to focus on the case study.
Students are periodically required to inform their "supervi-
sor" in writing concerning the progress made to date on the
case study, and a final design report is also required from
each team. The xylene-isomerization case study is the only


TABLE 2
Table of Contents
Chapter
1. The Assignment
2. What is Chemical Engineering?
What is Chemical Engineering?
What is a Chemical Process?
Flowsheets
The Impact of Chemical Processing and Chemical Engineering
3. Solving Engineering Problems (What Shall We Do?)
Strategies for Solving Problems
The Use of Teams in Solving Problems
4. Describing Physical Quantities
Units
Some Important Process Variables
5. Steady-State Material Balances (How Much Base Do We Need?)
Conservation of Total Mass
Material Balances for Multiple Species
6. Spreadsheets (Calculating the Cost of the Base)
The Calculation Scheme
Setting Up a Spreadsheet
Graphing
7. Fluid Flow (Bringing the Base to the Acid)
How Do Fluids Flow?
Pumps and Turbines: Examples of Fluid Flow Devices
8. Mass Transfer (Mixing the Acid and Base)
Molecular Diffusion
Mass Convection
Mass Transfer Through Boundaries
Multi-Step Mass Transfer
9. Reaction Engineering (How Fast Will the Reaction Go?)
Describing Reaction Rates
Designing the Reactor
10. Heat Transfer (Cooling Down the Product)
Energy Balances for Steady-State Open Systems
Some Applications of the Steady-State Energy Balance
Heat Exchange Devices
11. Materials (From What Shall We Build the Equipment?)
Metals and Corrosion
Ceramics
Polymers
Composites
Strength of Materials
12. Controlling the Process
Strategies of Process Control
How Do Computers Talk to Equipment
13. Economics (Is It All Worth It?)
Costs
Profitability
Economics of the Acid-Neutralization Problem
14. Case Study (Integrating It All Together)
The Problem
Using Engineering Teams for this Case Study

Chemical Engineering Education











case study currently included in the textbook. Thus, it has
been reused from year to year, in spite of the risk that
students may copy reports from previous semesters. We
have not found this to be a problem so far, probably because
of the honor code at BYU, but we do recognize the value of
developing additional case studies for future use.

In order to teach first-year students with varying back-
grounds, the course was designed with few prerequisites.


TABLE 3
Example Used in Course
Species A in liquid solution (concentration=0.74 M) enters a CSTR at
18.3 L/s, where it is consumed by the irreversible reaction
A C
where rreaction,A = krCA (kr = 0.015/s and cA is in units of gmol/L)
What reactor volume is needed so that the concentration of species A
leaving the reactor equals 0.09 M? The density can be assumed to be
constant.
SOLUTION (Note that the steps correspond to the instructions in
Tables 5.1 and 5.2.)
Drawing a diagram for this problem:
",n=18.3L/s c,, =0.74M-"i I rA- C
'L" Arreaction,A = (0.015/s) cA
volume=V -o, = ? CA ot= 0.09 M

As outlined in Table 5.2, we want to construct a mole balance on A.
For this case (for a single input and single output stream), the mole
balance becomes
A.in + rformatlon,A -= A,out rconsumption,A
Species A is being consumed, but no species A is being formed, so
rformationA = 0. This, along with substituting more convenient forms
for the molar flow rates, gives
CAin + in = CAout outt +rconsumption.A (a)
The value of the outgoing volumetric flow rate is not specifically
given, so we need a total mass balance, which for a single input and
single output stream, is
min = mount
which, in more convenient terms, is
PinVin = Pout Vout
Since the density is constant, this reduces to
Vin = Vout =V (b)
We can now calculate rconsumptionA using Eqs. (a) and (b). Equation
(a) becomes

rconsumption.A = CA;,n in -cAo,,, out = (CA, -CAout
( gmol gmol )( L) gmol
= 0.74- 0.09 18.3-- = 11.9
I L L )A s s
Up to now, everything we've done is a repeat of the material balances
we learned in Chapter 5. The new step is to equate the rconsumption,A
term to the given rate expression times the reactor volume, where CA
(in the reactor) = CAout

rconsumptionA krcAou )V
or

V rconsumptionA 11.9gmol/s 8,800L
c ,, =8,800L
krCA1 0.015 09gmol
rAut 09 L


Specifically, we did not assume any previous exposure to
calculus. We also assumed only a minimal knowledge of
chemistry, such as provided by even a mediocre high-school
chemistry class. Finally, while the course requires minimal
computer word-processing experience, it does not require
prior exposure to computer spreadsheets.
There are several other aspects of the day-to-day operation
of the course that may be of interest to the reader. For
example, the course includes frequent use of group activi-
ties, which serve to hold student interest, increase learning
effectiveness, and help first-year students form friendships
with one another. In-class quizzes are also used to motivate
students to keep up with their learning (a particular problem
for many first-year students who developed the habit of last-
minute cramming in high school). Classroom demonstra-
tions and examples from everyday life are used to illustrate
the chemical engineering principles being discussed. Small
pieces of equipment, such as pumps and heat exchangers,
are partially disassembled and passed around during class
for students to examine; photographs of larger equipment
items are also used.

Outside the classroom, we assign reading questions to be
answered for each new reading assignment before the mate-


TABLE 4
Example Used in Course

A heavy oil stream must be heated to a higher temperature, so the
decision is made to use a heat exchanger with saturated steam being
condensed to saturated water as the heating source on the other side of
the exchanger. The characteristics of the oil are
Oil mass flow rate: 960 Ibm/min
Oil mean heat capacity: 0.74 Btu/lbmF
Oil inlet temperature: 350F
Desired oil outlet temperature: 110F
The saturated steam has the following properties:
Steam temperature: 280F
Heat of vaporization (@280"F): 925 Btu/lb,
What steam flow rate is needed for this exchanger?
SOLUTION

Saturated steam, Saturated water,
280F, rt,,,am 280F, rh,,,s
Oil, 110F, 960 lbm/min Oil, 350F, 960 Ib,/min

For this problem, the oil is the cold stream and the steam/water is the
hot stream. For the oil side, Eq. 10.24b gives

Qduty [nm (Tout -Tinoi)]

= 960- m 0.74 Btu (11035F) 53,280B
I min lbm F) mm
For the steam/water side, as indicated in Table 10.2, for condensation
AHphase change = -A vaporization
so Eq. (10.24c) gives

-Qduty -53,280Btu/min Ib
msteatm -57.6-
-AHvap -925Btu/lb, min


Winter 1998










rial is discussed in class, and we assign homework problems
for the material after it has been discussed in class. Other
course features include the case study, which has already
been described, two mid-term examinations, and a final exam.
Grading is performed according to predefined criteria in
order to encourage cooperation between students.
As mentioned previously, this introductory experience is
completed in a two-credit-hour one-semester course. Thus,
the resources expended are relatively minimal, while our
experience indicates that the benefit derived is significant.

RESULTS
We have now taught the course for four years, and student
response has been very positive. At the end of every semes-
ter, all courses in our department are subjected to a student
evaluation questionnaire, which includes numerical scores
to specific questions and the opportunity for students to
make unrestricted comments. The numerical scores for the
introductory course have consistently corresponded to an
overall rating of "excellent" and are among the highest in the
department. We also send a questionnaire to all students who
change their major from chemical engineering to another
discipline. The comments from both of these types of ques-
tionnaires, along with feedback during informal conversa-
tions, indicate that students feel they have a much better
understanding of and appreciation for chemical engineer-
ing after having taken the course. Some comments from
those surveys are:
* "The course gave me a good idea of what to expect in my
major."
"The course is much more applicable to a business or
real-life situation than any course I have taken. "
"The course was EXTREMELY helpful in my decision to
stay with ChemE as my major. "
"The course has given me a good idea of what Chemical
Engineering is about. "
"I really enjoy this course. If it were up to my chemistry
class, I would drop out of ChemE. But this course shows
the light at the end of the tunnel. "
"Good prep (sic)for my major, applies concepts and
possible real life situations, but not too far over our
heads. "
"ChE 170 [was a] good class-I just knew after that one
that I didn't belong. "
"I enjoyed ChE 170, but I wouldn't like to do it for a
career.
In some cases, that knowledge has resulted in students chang-
ing majors to something other than chemical engineering.
That decision is judged to be positive if made with adequate
knowledge and experience.
The course appears to have slightly increased the overall
retention of students in the chemical engineering program,
but that is difficult to verify at this time. The difficulty arises
because approximately 80% of the first-year students in our


program leave the university after the first semester or after
the first year to serve a two-year mission for the Church of
Jesus Christ of Latter-Day Saints. Some of those students
take our introductory course before leaving, while others
take it after returning. Those students who took the first-year
course in the last three years and then began serving their
missions have not yet returned for a full year of school, so
we are not able to determine if they will continue in the
program.
Where there are complete data, we have examined reten-
tion as defined by the percentage of first-year students who
eventually, but not simultaneously, took the subsequent course
in our program (our sophomore course in material and en-
ergy balances). During the five years before implementation
of our course, freshmen took FORTRAN programming as
the first-year course, and 40% eventually took the sopho-
more class. During the last four years, the new course has
been offered in both the first semester (enrollments ranging
from 86 to 105) and the second semester (enrollments rang-
ing from 47 to 76). For students who took the introductory
course during the first of those years, the retention was
higher, at 46%. We will continue to compile retention data
as they become available. We feel, however, that changes in
overall retention are less important than, and may not be a
good indicator for, the increased ability of first-year students
to intelligently decide if chemical engineering is a good field
for them (one of our main goals).
In addition to providing an overview of chemical engi-
neering, students felt that the introductory course helped
prepare them for future courses, particularly the course on
material and energy balances normally taken by sophomores.
This opinion was consistent with that of the course instructor
for the sophomore course, who observed that the students
who had taken the introductory course were better prepared
than previous students. The instructor also noted that the
students had a significantly broader knowledge of the disci-
pline. For example, when he mentioned to the students in the
class that phase equilibrium would be important in separa-
tion processes such as distillation, they recognized the pro-
cesses to which he was referring and appreciated the signifi-
cance of his statement.
Although a quantitative evaluation is difficult, other anec-
dotal information provides positive feedback about the course.
For example, two students who had recently completed the
introductory course requested help from one of the authors
to explore an issue in process control for use in a paper for a
technical writing class. Specifically, they wanted to explore
differences between feedback and feedforward control strat-
egies. The students were in the first semester of their third
year, a full year before they were scheduled to take our
senior-level process control class. Prior to the time we began
teaching the introductory course, students at the same point
in their education had little, if any, concept of process con-
Chemical Engineering Education










trol. Yet, these students had learned 70
enough in the introductory course to de- 60
fine a question and pursue the topic fur-
ther on their own. Incidentally, they were 50
supplied with a process simulation pro- % of 40
gram (PICLESi21) and were able to use Students 30
the program to address the issues of in-
terest. 20
It has also been our perception that 10
the course has served to help build rela- 0
tionships between students. They appear 0-2
to be working in groups and helping
each other much more than they did pre- Figure 2. Number
viously. This interaction is facilitated outside of cl
by the group work required as part of
the class. Also, grading is structured so that students do not
perceive that they are hurting their own grade by helping
their classmates. Interaction between the faculty member
teaching the course and the students has also been very
positive. In many cases this has resulted in continued
interaction and discussions, exchange of e-mail, sharing
of wedding announcements, etc., long after the final exam
is taken.
In order to provide the desired integrated overview, it was
necessary to cover a broad variety of chemical engineering
concepts. We were concerned that in doing this we might
overwhelm the students with too much material. Like most
schools, our target for work outside of class (reading and
homework problems) is two hours outside class per one hour
inside. For a two-credit class (two hours per week in class),
this translates to four hours per week outside of class. A
recent polling of all our students concerning the time they
spend in class work outside of class indicated that the
workload for the introductory course was on target at an
average of approximately 3-4 hours a week. We conclude
from this that the students have not been overwhelmed by
the material presented in class.
Finally, the written material for the course has evolved
considerably over the past four years, but has now stabilized
to a large extent. As mentioned previously, we have recently
published a textbook'1 for the course that is available for
others who may be interested.
We end this section by noting that the course described in
this paper has an appeal that extends to other situations
where beginning students need to know about chemical en-
gineering. For example, some colleges have a common fresh-
man engineering course, and the chemical engineering de-
partments do not see the students until the sophomore year.
In those cases, the course described here could be given to
first-semester sophomores prior to the traditional course on
material and energy balances. It could also be used in two-
year colleges from which students may transfer into our
programs.
Winter 1998


2-4 4-6 6-8 >8
Hours
of hours per week spent
ass on this course.


CONCLUSION
A new introductory course has been
developed for first-year students inter-
ested in chemical engineering. This two-
credit-hour one-semester course is de-
signed to provide a broad overview of
the chemical engineering discipline and
a foundation for other courses in the
curriculum. Other objectives for the
course include the introduction of fun-
damental principles related to chemical
engineering, connection of material
to the students' experiences and fu-
ture coursework, introduction of de-


sign concepts, and development of
student/faculty and student/student relationships. Student
feedback, although qualitative, indicates that the course
has been largely successful in accomplishing these ob-
jectives.
The laying of a broad introductory foundation at the be-
ginning of a long academic program was of particular inter-
est and importance. Consequently, the course was designed
to establish the framework for the rest of the curriculum. Our
intention was to facilitate learning by providing an overview
and establishing connections so that in-depth material from
upper-division courses could readily be integrated into an ex-
isting framework, rather than waiting until a senior capstone
course to attempt to tie things together. The approach also
facilitates learning through repetition by providing a first-year
exposure prior to the more-in-depth upper-division exposure.
We are providing this information so that other schools
may consider this approach for adoption into their programs.
Universities with no freshman engineering course may con-
sider adding a course like the one described here. Schools
with an existing general freshman engineering course might
consider replacing it with this course for students who are
seriously considering chemical engineering as a major.
Where this is not possible, this course might be offered
to sophomores in chemical engineering. In addition, two-
year colleges might use this course to prepare their stu-
dents for transferring to four-year chemical engineering
programs.
We are anxious to receive impressions and suggestions
from others who have seen our course or book, or who have
experience with similar attempts to prepare first-year stu-
dents for this discipline.

REFERENCES
1. Solen, K.A., and J.N. Harb, Introduction to Chemical Pro-
cess Fundamentals and Design, McGraw-Hill, New York,
NY (1997)
2. Cooper, D.J., PICLES (Process Identification and Control
Loop Explorer System), Version 4.1, Department of Chemi-
cal Engineering, University of Connecticut (1995) O
57











[efi curriculum
-.


FRESHMAN DESIGN PROJECTS

In the Environmental Health and Safety Department



RONALD J. WILLEY, JOHN M. PRICE
Northeastern University Boston, MA 02115


Freshmen usually come to us without an engineering
background. They are accustomed to working alone
on small, well-structured problems, do not under-
stand the laws of thermodynamics, and have little concep-
tion about conservation of momentum, energy, and mass.
Consequently, we have been reluctant to give open-ended
design problems to them in spite of the fact that the fun of
engineering is working on real problems and finding solu-
tions to them. It seems too big of a risk.
While incorporating engineering health and safety issues
into the engineering curriculum is desirable and has been
addressed by ABET,"m meeting this major challenge is diffi-
cult given the many other ABET requirements. Past papers
that address possible approaches include the work of Gute,
et al.,121 Bethea,13' and Rossignol, et al.141 Our approach intro-
duces students to open-ended problems early in the curricu-
lum. We find that their creative abilities provide fresh solu-
tions to mundane problems.

FRESHMAN CURRICULUM
Northeastern University has a five-year cooperative edu-
cation program in engineering. The freshman year has three

Ronald Willey holds BSc and PhD degrees in
chemical engineering from the University of New
Hampshire and the University of Massachusetts
(Amherst), respectively. He has six years of in-
dustrial experience in the paper industry and
has been at Northeastern University since 1983.
His teaching responsibilities include the Unit Op-
erations laboratory.


John M. Price is Director of Environmental Health
and Safety at Northeastern University. After re-
ceiving a BS and MS in chemical engineering
from Northeastern, he earned an MS in environ-
mental sciences from Harvard University. He has
fifteen years experience implementing and man-
aging occupational and environmental safety pro-
grams at academic research institutions.


While incorporating engineering health and safety
issues... is desirable and has been addressed by
ABET,11 meeting this major challenge is difficult... Our
approach introduces students to open-ended problems
early in the curriculum.... their creative abilities
provide fresh solutions to mundane problems.

quarters, and upperclassmen take two quarters of classes and
of cooperative education during each of the next four years.
The result is eleven quarters of classroom training and seven
or eight quarters of industrial experience.
To allow freshmen the opportunity to meet College of
Engineering (COE) faculty early in their academic career,
COE faculty take an active role with freshman engineering
students. Engineering courses offered in the freshman year
are
*C-programming during the fall
*Problem solving using spreadsheets and MathCad in the winter
*Engineering design in the spring
The engineering design course is divided into ten sections,
with about thirty students in each section. The sections meet
for 65 minutes three times a week. Our quarter system al-
lows for just under eleven weeks of classroom meetings
each quarter. Sections are divided by intended major and
assigned to faculty from the appropriate departments. This
paper is devoted to declared chemical engineering majors.
Engineering design uses a textbook developed by
Northeastern's Gerald Voland, Engineering by Design.15 He
breaks down the design process into key stages that include
1) Needs determination
2) Design goals and specifications
3) Abstraction
4) Evaluation of alternative designs
5) Ergonomic analysis
In general, engineering design students are assigned a minor


Copyright ChE Division ofASEE 1998


Chemical Engineering Education




















































TABLE 2
Major Design Projects, Spring 1996


# Department
1. Mail Services
2. Mail Services

3. Physical Plant

4. Physical Plant
5. Environment Health

6. Environment Health

7. Environment Health

8. Environment Health


9. Environment Health


Location Contact Project Description
Basement J. Devine Workstation lighting evaluation
Basement, Columbus PI. J. Devine Noise level survey for letter-stamping
machine
Mail room, Columbus PI. J. Devine Employee fall protection from loading
docks


Various
Various laboratories

Various dark rooms

Various computer labs

Various laboratories


Various laboratories


10. Chemical Engineering 8 Mugar


B. Mitcheson Loading-dock assessment
S. Brehio Quality control check on safety show-
ers and eye-wash station survey
S. Brehio Evaluation of silver recovery options
for environmental compliance
J. Price Ergonomic evaluation of computer
workstations
S. Brehio Opportunities for waste minimization
in the generation of HPLC solvent
waste
S. Brehio Strategies, facility requirements, and
costs for a central organic solvent bulk-
ing facility
A. Bina Design of flow measurement experi-
ment


TABLE 1
Proposal Outline for Student Project Design Submittal

GE1103 Spring 1996
Minor Design Project Due April 23, 1996
"If there isn't a need why bother?" R.J. Willey 4/5/96
Summary:
Excellent designs begin with a proper needs assessment and the correct statement of the problems to be
solved. An excellent example of posing the proper questions before solving the problem at hand is space
craft reentry. Your group is to prepare a 5-page proposal (double spaced and 12-point Courier font) and a
5-minute presentation about your major design project. This work will be due on April 23, 1996. Mr.
Jack Price will review and assign grades on your oral presentations (25% of the total minor design project
grade). Each group must go to the front of the classroom. After a brief introduction from each group
member, one of your group members should serve as a spokesperson. That person should briefly define
the need, the problem to be solved, and the methods to be used.
Proposal Outline
Objectives
Using a numbered list, state your objectives. Be as precise as possible.
Background
Who will be served by your solution/design? Where will your solution/design be used? What is the
past history related to the problem? Are there any important references related to the problem that you are
working on? Existing solutions and prior work on the problem should be described.
Methodology
Focus on what techniques you will use to help you solve the "problems" and succeed with a successful
design. Use Prof. Voland's and class notes to obtain methods on how to proceed.
Proposed Schedule Include a proposed schedule that is similar to the schedule shown in Figure 2.6,
page 88. Use weeks as the time period and adjust phases to match your problem/design.
Person Loading Chart Include a person loading (Gantt) chart like the one shown in Figure 2.7. Use
hours as the time period and adjust the task list to match your problem/design requirement.
Autocad Drawing Include a schematic or layout drawing for the project that you are working on.
Expected Results
Begin with the end in mind. What are the "deliverables"? Who will benefit?
Costs What will be the costs involved? "Personpower" can be estimated at a direct cost of $45.00/hr.
Other costs will involve materials and supplies to bring about the solution/design (not the cost of the final
recommended design).


and a major design project, each to
be completed using the methods pre-
sented in Voland's text. In the
chemical engineering section, these
minor and major projects address
the same problem. Our minor de-
sign project (see Table 1) consists
of a needs assessment and proposed
approach to one of the major design
projects listed in Table 2. The ma-
jor design project is execution of
the actual work proposed.
Students are divided into groups
of three at the second class meet-
ing, providing a total of ten teams.
Each team selects a project from
Table 2-no duplication is allowed.
Each team's interests are matched
to a project.
Each project assigned to a team
has a University administrator who
serves as the "client." The student
teams serve as consulting engineer-
ing services. Additionally, our Of-
fice of Environmental Health and
Safety (OEHS) serves as a mentor
and an interface between the clients
and the consultants.
As Table 2 shows, design projects
vary from noise surveys in the Uni-
versity mail room to the optimiza-
tion of hazardous waste disposal.
The projects introduce students to
survey instruments, to data evalua-
tion, to regulatory compliance is-
sues, and involve interaction with a
variety of people. Students begin
learning engineering principles (e.g.,
velocity measurements involving
Bernoulli's equation), team skills,
communication skills (written and
oral), and economics. With a little
investment and some oversight by
the OEHS, the University benefits
from the students' project recom-
mendations (discussed in more de-
tail below).
The minor and major assignments,
the proposal, and the design solu-
tion comprise 55% of the course
grade. The remaining portion is
based on two examinations (30%)
and daily homework assignments
59


Winter 1998











(15%). AutoCad is also presented in this class
(about one third of the lectures), and students are
encouraged to make drawings of their major
assignment using it.

As with any open-ended term project, students
tend to put off work until the last minute, with
the usual disastrous results. To avoid this out-
come, students are required to submit a weekly
log book and are given small assignments that
push them 1) to get their groups together, 2) to
begin meeting with their contacts, 3) to obtain
background information, and 4) to work towards
a solution. The logbook system also serves to
identify early such problems as an inability to
connect with the University contact or the exist-
ence of a nonparticipating member.

For the instructor, the project process is simi-
lar to managing a small consulting firm made up
of all "rookie" teams. The students generally
find their contacts during the first week and will
begin the literature checks, but then their meth-
ods diverge. One year, two seniors were inten-
tionally recruited to work with two freshman
team members. With the advantage of the se-
niors' co-op and military experience, the teams
attacked their project with vigor. Both design so-
lutions-the redesign of a loading-dock area and
the creation of a safety check list (see Table 3)-
are now being implemented by the University.

Eight of the ten groups functioned well. Their
final designs were quite good. They succeeded,
in part, because they were self-selecting and
they shared a general interest in working on a
real problem.

On the other hand, one of the eight all-fresh-
man teams was not successful. No previous en-
gineering work experience or effective leader-
ship existed within the group. One student made
his initial contact with the client regarding the
design of a flow measurement system for two
centrifugal pumps. He quickly assessed the situ-
ation, claimed the solution was easy, and stated
that he should be done after just a few hours of
work. He never included the other team mem-
bers in the plans or their execution and they, in
turn, never tried to participate, expecting this
student to carry them through.

Other all-freshman teams turned in good-to-
excellent reports. One team worked the mail
room workstation lighting problem. As part of
their presentation, they built a 3-D model of the
room. The model ceiling had holes cut out at the


_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes
_yes



_yes
_yes
_yes
_yes
_yes
_yes
_yes

_yes
_yes
_yes
_yes
_yes
_yes
_yes


TABLE 3
Loading Dock Safety Checklist
Generated by Students Who Worked on Project #3


General Area
no Are loading positions for trucks marked with lines?
no Are dock guards in operable condition?
no Are loading areas free of potholes?
no Are floors cleaned daily?
no Are trash containers emptied daily?
no Are trailer wheel chocks provided for each truck?
no Are trailer wheel chocks chained to the building?
no Are proper warning signs clearly visible for general safety issues?
no Is ventilation adequate?
no Is lighting adequate?
no Does the dock have a roof?
no Does roof of dock have a drainage system (i.e., gutters)?
no Is dock within height accordance of all trucks that will use the dock?
no Are proper signs posted instructing drivers to turn off their engines?
no Are first-aid kits readily available?
no Are emergency telephones easily accessible?
no Are fire extinguishers/sprinkler systems in working order and accessible?
no Is noise level of dock in accordance with federal regulations?
no Is dock equipped with handrail?
no Is dock marked with vivid paint to display hazardous areas?
no Are emergency exits provided, marked, and kept clear?
no Are foot rails in place at the edge of the dock?
no Are mirrors provided for "blind spots"?
no Are storage areas of equipment, pallets, machinery marked and kept clean?
no Are areas for drivers provided during loading and unloading?
no Are pedestrian walkways clearly identified?
no Are incline of ramps used for hand loading/unloading not too steep?

Training and Personnel
no Is safety and health training provided to dock personnel?
no Are employees tested or evaluated on their knowledge of safety procedures?
no Are refresher courses in safety and hazard prevention provided to workers?
no Are dock personnel trained in the use of bridge plates or dock levelers?
no Are dock personnel trained in the proper care of heavy packages?
no Are visitors given protective wear and area away from dock to congregate?
no Are dock personnel familiar with using a manual and motorized equipment?
Are dock personnel provided with safety equipment (if applicable)
no Hard hats
no Weight belts
no Gloves
no Eye protection
no Ear protection
no Footwear
no Are dock workers trained to secure loads for transport?


The above checklist is based on a ranking system of I to 3 points per question. A (3) is deemed
critical, a (2) is deemed important, while a (1) is deemed optional. To find your total possible
score, add the possible points column, disregarding those questions that are non-applicable. For
each question answered "yes," give yourself the point amount given to that question. For each
question answered "no," add no points. Add all your scored points. This will give you your total
raw score. Now review your total raw score and make sure it complies with the following:
All the questions given a rank of(3) are answered "yes."
At least 80% of the questions given a rank of(2) are answered "yes."
Questions with a ranking of(l) are left to the discretion of the proper management.
If these compliances have been met, then your dock is in accordance with the safety measures we
require. If this is not so, then adjustments and modifications must be made until the requirements
are met.


Chemical Engineering Education










existing lighting-fixture locations, and
using a simple flashlight shining from
above, the students were able to dem-
onstrate the inefficiencies of the light-
ing grid. They then demonstrated how
the placement of two additional light-
ing fixtures over the proper work area
could correct the lighting. By ex-
changing the top of the 3-D model
with the properly modified ceiling
and shining the light through it, they
were able to present their solution
efficiently and observably.
Since students have generally been
conditioned to work individually prior
to entering college, one of our big-
gest challenges was getting them to
work together. While team work is a
novelty in the academic environment,
when these students take on their first
industrial co-op assignment, team
work is often the expected mode of
operation. An important feature of
our approach is to develop team-
working skills. Figure 1. Student
Another related challenge was the model made
division of work. While eight of the related to saj
ten student teams handled the divi-
sion of work quite well, in one team there was one student
overly concerned about the "grade" and another more con-
cerned about what he was "really learning." These two never
reached a consensus about what the professor wanted and
ended up giving individual solutions. Meanwhile, the group's
third member watched in bewilderment while the other two
argued constantly during team meetings.
Another poorly functioning group had a clear cultural
divergence that led to little or no team effort. This group was
not self-selecting, having been formed of late registrants
who came to class for the first time on the second day. The
members were from different countries and did not know
each other previously. This team did not work well to-
gether primarily because one team member worked on
the problem by himself and didn't include the other two
members who, in this case, were satisfied that someone
else was going to do the work.
We required two group reports and two presentations dur-
ing the quarter. The first report was the proposal for the
"client's approval" and was due about midway into the quar-
ter. The corresponding presentations were limited to five
minutes per group and were given on the day the propos-
als were due. The second, formal report described the
final design solution intended to meet the client's needs.
The second presentations were twenty minutes each and
Winter 1998


hold
for
fetys


consisted of a summary of the design
solution.
Several models, iconic (resembling the
situation but not having the functionality)
and analogic (not resembling the situation
S but having the functionality) were made
by the groups as the projects progressed.
-; Figure 1 shows one example of student
S creativity. The model shower pictured was
made to help explain design requirements
for American With Disabilities ACT com-
pliance concerns.
Another group built a scale model of a
process to recover silver generated in the
University's photo labs. This model was
constructed so that each major functional
component could be removed. The stu-
dents used the model during their presen-
tation to help the class understand the func-
tionality of their proposed silver-recovery
system. The presentation was extremely
rewarding for the class and the instructor.

CONCLUSIONS
ling an iconic Open-ended, real problems are challeng-
'roject #5 ing to make work in the classroom. There
showers.
showers. is no instructor's solution manual avail-

able and each project is demanding, re-
quiring constant attention by the instructor. Project paths
can change as the quarter progresses. Common difficult
situations center around a contact not responding or a
group member not participating. Sometimes, design prob-
lems are too vague.
We encourage others to contact their Environmental Health
and Safety departments to discuss a similar approach at their
University. Not only will their students learn to alleviate
persistent campus hazards, their school just might gain some
inexpensive physical improvements.

REFERENCES
1. ABET, Criteria for Accrediting Programs in Engineering in
the United States, Engineering Accreditation Commission,
Accreditation Board for Engineering and Technology, Inc.,
New York, NY (Sections IV.C.2 and IV.C.3) (1994)
2. Gute, D.M., A.M. Rossignol, N.B. Hanes, and J.T. Talty,
"Factors Affecting the Performance of Occupational Health
and Safety Topics in Engineering Courses," J. Eng. Ed., p.
163, July (1993)
3. Bethea, R.M., "Engineers Encourage Universities to Em-
phasize Safety in Curriculum," Occ. Health & Safety, p. 22,
June (1992)
4. Rossignol, A.M., and N.B. Hanes, "Introducing Occupational
Safety and Health Material into Engineering Courses," Eng.
Ed., p. 430, April (1990)
5. Voland, G.M., Engineering by Design, Addison Wesley Publ.
Co., Reading, MA (1998) 0










lff curriculum


INNOVATIVE WAYS

OF TEACHING POLYMERIZATION

REACTION ENGINEERING

Exchanging Information Between the University and Industry


JoAo B. P. SHARES, ALEXANDER PENLIDIS, ARCHIE E. HAMIELEC*
University of Waterloo Waterloo, Ontario, Canada N2L 3G1


he polymer industry is one of the most important and
fastest growing segments of the chemical industry
today, and this growth has created a high demand for
professionals with adequate knowledge to attend to its very
special needs. Besides the classical core subjects of the
chemical engineering curriculum, knowledge of several ad-
ditional topics is required for the student who intends to
apply for a position in the polymer manufacturing industry.
The technology for polymer manufacture is in a constant
state of change, and any undergraduate or graduate program
that relies only on established approaches in polymer chem-
istry and physics will quickly find itself out of date. In this
article we will describe how our interaction with several
polymer manufacturing companies through industrial short
courses and research projects has led to the development of a
dynamic and up-to-date undergraduate and graduate curricu-
lum in polymer science and engineering technology.
The technology for polymer production is a very dynamic
field due to the high demand for polymeric materials with
entirely novel or improved properties. New discoveries and
applications in polymerization catalysts and initiators, in
polymer reaction engineering, polymer characterization, and
polymer processing frequently redefine the boundaries of

Jodo B. P. Shares received his BEng (1983) from Federal University of
Bahia, Brazil, his MSc (1985) from State University of Campinas, Brazil,
and his PhD (1994) from McMaster University, all in chemical engineer-
ing. His main research interests are in the fields of metallocene and
Ziegler-Natta polymerization.
Alexander Penlidis received his Dipl. Eng. (1980) from the University of
Thessaloniki, Greece, and his PhD (1986) from McMaster University, both
in chemical engineering. His interests lie in the areas of polymer reactor
modeling, design, optimization, and computer control.
Archie E. Hamielec joined the chemical engineering department at
McMaster University in 1963, took early retirement in 1993, and is cur-
rently a Professor Emeritus. He is actively engaged in consulting for the
polymer manufacturing industry.

* McMaster University, Hamilton, Ontario, Canada L8S 4L7
62


knowledge in polymer science and technology. As a result,
several of the leading technologies for polymer manufacture
are constantly being modified to meet new market demands.
Although it is stimulating for those involved in the field,
this dynamic pace nonetheless creates a significant concern
for instructors teaching polymer-related courses in academia
since it requires that both undergraduate and graduate courses
be regularly updated to reflect these new developments.
Keeping up to date with the scientific literature alone, even


TABLE 1
Partial List of Scientific Journals
in Polymer Science and Engineering

Journal Name (Periodicity) Publisher
European Polymer Journal (Monthly) Pergamon Press
International Polymer Science and Tech. (Monthly) RAPRA
Journal of Applied Polymer Science (Quarterly) John Wiley & Sons
Journal of Macromolecular Science (Monthly) Marcel Dekker
Journal of Polymer Engineering (Quarterly) Freund Pub. House
J. of Polymer Sci.: Poly. Chem. (Month/Semi-Month) Wiley & Sons
J. of Polymer Sci.: Poly. Phy.(Month/Semi-Month) Wiley & Sons
Macromolecules (Bi-Weekly) American Chem. Soc.
Macromolecular Reports (8 per Year) Marcel Dekker
Macromolecular Symposium (Irregular) Hiithig & Wepf Verlag
Polymer (Bi-Weekly) Elsevier
Polymer Bulletin (Bi-Monthly) Springer
Polymer Engineering and Science (Semi-Monthly) Soc. of Poly. Eng.
Polymer International (Monthly) John Wiley & Sons
Polymer Journal (Monthly) Soc. of Poly. Sci., Japan
Polymer Reaction Engineering Journal (Quarterly) Marcel Dekker
Progress in Polymer Science (Bi-Monthly) Pergamon Press
Trends in Polymer Science (Monthly) Elsevier


Copyright ChE Division ofASEE 1998
Chemical Engineering Education











in a relatively narrow branch of polymer science and
engineering, can be a time-consuming task due to the
numerous scientific journals available in the field, some
of which are listed in Table 1.
The polymer science and engineering theme illus-
trates remarkably well the old saying that in order to
teach a subject well, one must be actively involved in
research in that subject. That is the only way one can
stay current with all the new developments and main-
tain a sense of coherence and relevance in the face of
the immense body of information available to academ-
ics nowadays.
An additional and equally important point to remem-
ber when designing an academic course, especially at
the undergraduate level, is that equal importance must
be given to both scientific-relevant topics and those
that are of immediate concern to industry, since most
students will be seeking industrial jobs after gradua-
tion. Results from recent surveys on employment in the
United States and Europe indicate that as many as 70%
of chemical engineering graduates will have worked with
a polymer-related industry at some point in their profes-
sional career. Unfortunately, the importance of polymer
courses for chemical engineers at the undergraduate level
is still overlooked in several academic institutions.
In this article, we will describe our instructional ef-
forts in polymer science and technology at three dis-
tinct levels: industrial-intensive short courses, academic
courses, and final-undergraduate-year design and re-
search projects. We will show how these activities
complement each other, leading to university courses
with a high content of industrially relevant material
and to industrial courses that bring recent academic
advances in polymer science and engineering to in-
dustrial applications.

INDUSTRIAL SHORT COURSES
We offer three courses annually in Canada, the United
States, and Europe. Although the details of these courses
might vary according to the type of audience they are
intended for, they combine a very strong component in
fundamental understanding of polymerization reaction
engineering with recent advances in several aspects of
polymerization processes. In addition to the regular
lecturers, invited speakers (mainly from industry,
but also from academia) are regularly asked to give
two- to four-hour lectures. It has been our experi-
ence that the material covered by the invited speak-
ers is highly relevant to our industrial short courses
and can be successfully used to complement the
content of our university courses.
Table 2 shows the syllabus of a recent industrial
intensive short course in polymerization chemistry and
Winter 1998


)v Sessions
1 Chain-Growth
Polymerization
Mechanisms and
Kinetics


TABLE 2
Syllabus of Industrial Short Course

Toics
* Linear, branched, and crosslinked chains via free-radical
polymerization
* Linear and branched chains via ionic mechanisms
(Ziegler-Natta and Metallocenes)
* Stockmayer's bivariate distribution-instantaneous property
methods


Advanced Identification of multiple active site types (GPC,
Polymerization TREF, NMR)
Kinetics Identification of active site performance
Long chain branching
Ziegler-Natta and metallocene catalysis
2 Emulsion, Styrenics, PVC
Dispersion, and Batch, semi-batch, and continuous operation
Suspension Thermodynamics and surface chemistry
Processes Particle nucleation and growth
Ionic and steric stabilization
Particle size distribution and molecular weight distrib.
Polyolefinic Molecular, theological, and solid-state properties (LDPE,
Processes HDPE, LLDPE, PP, impact copolymers)
Effect of short and long chain branching and molecular
weight distributions
Effects of main process variables on productivity and
polymer properties
Models of polyolefin production processes and plant data
comparisons
3 Principles of Batch, semi-batch, and continuous operation
Polymer Reactor Dynamic modeling of reactor systems
Modeling and Population balance equations for particle size and molecular
Kinetic Data weight
Collection Screening and factorial designs for data collection
Sequential and non-linear design of experiments
Evolutionary operation
Model discrimination issues
4 Modem Special Bulk, solution, and emulsion terpolymerizations
Topics Reactivity ratio estimation
Monte Carlo methodology and applications
Reactivity ratio estimation
Optimal sensor selection
Reactive processing
Principles of temperature rising elution fractionation (TREF)
Measurement of long chain branching (GPC/VISC/LALLS)
Chemical modification of polymers
Crystallization Analysis Fractionation (CRYSTAF)
Rubber Definitions of rubbers and elastomers
Manufacturing Synthesis and production of rubbers
Processes and Recent developments in EP(D)M and poly- a -olefins:
Product metallocene catalysis/gas phase process/single site vs.
Characterization multi-site catalysts
Molecular structure and physical properties
Compounding, vulcanization, and applications
5 Monitoring, Overview of current control practices
Dynamics, and Sensors for monitoring reactor behavior
Control of Energy balance and rate control
Polymerization Control of product properties
Reactors Model use to combine on-line and off-line data
Kalman filtering and inferential control
Software sensors and multivariable statistics
Optimal reactor grade changes
Advanced linear and nonlinear control











reaction engineering, with emphasis on
metallocene catalysts, emulsion, and suspension
polymerization processes. As can be seen, the
first three sessions concentrate on fundamentals
and mathematical modeling of coordination and
free-radical polymerization. This forms the basis
for understanding of the more applied topics cov-
ered in subsequent sessions.

Properties of polyolefin resins and rubbers, es-
pecially structure-property relationships, are
given special attention. Recent advances on re-
actor monitoring, dynamics, and control, as well
as kinetic data collection and analysis, are also
covered in depth.

A session on modern special topics is generally
offered to cover new technologies and research
topics in polymer science and engineering. Mod-
em polymer characterization techniques are gen-
erally covered in the last session, although they
are discussed at every available opportunity dur-
ing the previous sessions, including applications
of on-line sensors.

As mentioned before, invited speakers make an
important contribution to this instructional effort.
Table 3 lists the names, topics, and affiliations of
some of the invited speakers who have partici-
pated in our courses in the past five years.

In-house short courses are also offered to meet
the needs of specific companies. These in-house
courses may range from one to five days. They
can be as general as the course described in Table
2 or focused on the technologies of the specific
company. Possibilities also include combinations
of special topics: for example, a two-day update
on the use of statistical methods and the design of
experiments for polymerization processes. Table
4 shows the syllabus of such a course on polymer
reaction engineering of polyolefinic processes re-
cently given in the United States. This particular
course concentrated on the manufacture of
polyolefins, with special emphasis on new tech-
nologies for metallocene catalysts.

It has been our experience that these courses are
mutually beneficial for the industrial participants
and for the lecturers. On one hand, the industrial
participants have an opportunity to update their
knowledge of modern advances in a broad area of
polymer science and technology, and over the
years we have been glad to note that several in-
dustrial participants have initiated research col-
laborations with the instructors after taking the
courses and that some of the topics introduced


TABLE 3
Partial List of Invited Speakers, Their Topics, and Affiliations


Dr. T.A. Duever


Design of experiments for
polymerization data collection


Dr. G.N. Foster Characterization and physical
properties of polyolefins


Dr. E. Kontos
Dir., Elastomers
Technology


Dr.


Chem. Eng. Department
University of Waterloo


Union Carbide
Bound Brook, NJ


Rubber manufacturing processes Uniroyal Chem. Co.
and product characterization Naugatuck, CT


K. Malone Organic peroxides for free- Elf Atochem.
radical polymerization Buffalo, NY


Dr. B. Monrabal

Dr. G.L. Rempel

Dr. C. Tzoganakis


Introduction


Crystallization analysis
fractionation (CRYSTAF)
Metallocene catalysis and cata-
lytic modification of polymers
Polymer processing and reactive
extrusion


Polymer Character., S.A.
Patera, Spain
Chem. Eng. Department
University of Waterloo
Chem. Eng. Department
University of Waterloo


TABLE 4
Syllabus: In-House Short Course for
Polyolefin Production and Characterization

Soluble vs. heterogeneous catalysts
Polymerization mechanisms: homo- vs. copolymerization/linear
vs. branched chain formation
Control of stereoregularity, molecular weight, short and long
chain branching
Effect of polymer microstucture on mechanical and theological
properties


Polymerization Gas phase/slurry bulk monomer and diluent/solution
Processes Fluidized bed vs. stirred bed gas-phase reactors
Loop reactors vs. stirred-bed slurry reactors
Processes for manufacture of high-impact copolymers
Vis-breaking processes


Basic Mathematical
Modeling
Techniques
Advanced
Mathematical
Modeling of
Polymerization
Processes


Catalytic Site Type
Identification




Reactor Dynamics
/Control/Grade
Transitions


* Mass balances: batch, semi-batch, and continuous operation of
CSTRs and CSTR trains
* Energy balance
* Polymerization kinetics
* Population balances
* Instantaneous properties methods vs. method of moments
* Multiplicity of active sites
* Heat and mass transfer limitations
* Particle size distribution

* Deconvolution of GPC curves using Flory's most probable
distribution
* Deconvolution of TREF curves using Stockmayer's distribution
* GPC/LC-transform-a new approach to site identification
* CRYSTAF and CITREF
* Overview of current control practices
* Sensors for monitoring reactor behavior
* Energy balance and rate control
* Control of product properties
* Model use to combine on-line and off-line data
* Kalman filtering and inferential control
* Software sensors and multivariable statistics
* Optimal reactor grade changes
* Advanced linear and nonlinear control


Chemical Engineering Education












The technology for polymer manufacture is in a constant state of change, and any
undergraduate or graduate program that relies only on established approaches in polymer chemistry
and physics will quickly find itself out of date. In this article we will describe how our interaction with
several polymer manufacturing companies ... has led to the development of a dynamic and up-to-date
undergraduate and graduate curriculum in polymer science and engineering technology.


TABLE 5
Syllabus for Polymer Reaction Engineering Course

Week Topics
1 Overall course objectives Basic concepts and definitions in polymer science
2 Definition of molecular weight averages and distributions Method of moments *
Analytical techniques for measuring molecular weights
3 Step growth polymerization Condensation vs. addition polymers Statistical
treatment of step-growth polymerization Equal reactivity assumption (ERA) *
Irreversible growth with ERA Carothers equation Flory-Shultz distribution *
Determination of kinetic constants
4 Stoichiometry of linear systems Generalized Carothers equation Deterministic
treatment of step-growth polymerization Modeling step-growth polymerization
without ERA Effect of monofunctional agents Reversibility and interchange
reactions
5 Free-radical homo- and copolymerization Initiation, propagation, and termination
Basic hypotheses Commercial initiators Initiation rate Isothermal operation *
Initiator efficiency Propagation characteristics
6 Chain conformations Tacticity Termination characteristics Choice and amount
of initiator Inhibition and retardation Impurities Development of equations for
polymerization production rate Homopolymerization in batch reactors Dead-end
polymerization
7 Derivation of the instantaneous copolymer composition (ICC) equation Plots of
the ICC equation Reactivity ratios Introduction to composition control methods *
Meyer-Lowry equation Cumulative copolymer composition Depropagation *
Molecular weight (MW) development for linear homopolymers
Mid-Term Exam
8 MW development: averages and distributions Practical hints on MW control and
temperature programming Energy balances Temperature and controller design *
Modes of termination Reactions with chain transfer agent Chain transfer to
monomer MW development: branched homopolymers
9 Transfer to polymer Terminal double-bond and internal double-bond reactions *
Backbiting Industrial examples Method of moments for branched systems MW
development for linear and branched copolymers Effect on glass transition
temperature Bimolecular termination kinetics
10 Emulsion polymerization: contrast with other polymerization methods Nucleation
and growth Thermodynamics Free-radical concentration Emulsion polymeriza-
tion kinetics: homo- and copolymerization
11 Latex particles size Polymer molecular weight Effects of pH and ionic strength *
Impurities Coagulation Multiple phase latex particles Introduction to
mathematical and computer modeling
12 Ionic (anionic and cationic) and coordination (Ziegler-Natta and metallocene)
polymerizations Brief overview Mechanisms Polymer properties
13 Review Sample problems and general discussion on the design of large polymer-
ization reactors
Final Exam

Winter 1998


during the courses have found practical appli-
cations in industry. On the other hand, the in-
structors benefit greatly from these interactions
since the contacts permit them to stay "in tune"
with the current needs of industry and with
recent advances of a practical nature that very
often are not disclosed in the scientific litera-
ture. This is not only a good way of influencing
the direction of some of our applied research,
but also an excellent way of covering current
trends of the polymer industry in our university
courses. Our students enjoy, and benefit tre-
mendously from, a knowledge of these current
industrial trends.

UNDERGRADUATE COURSE
Table 5 presents the syllabus of the introduc-
tory polymer course given in the Chemical En-
gineering Department at the University of Wa-
terloo. It is offered annually (6 hours per week)
as a technical elective course for senior un-
dergraduate students and as an introductory
course for graduate students who are pursu-
ing MASc and PhD degrees in polymer sci-
ence and engineering.
This course covers the main areas of polymer
reaction engineering for step-growth and chain-
growth polymerization. Special emphasis is put
on understanding fundamental polymerization
principles, using both experimental polymer-
ization data and mathematical modeling tech-
niques. The statistical nature of polymerization
is examined in detail together with the concepts
of molecular weight and chemical composition
distribution in polymers. Polymer characteriza-
tion techniques are introduced as tools to corre-
late polymer chain structure to polymerization
mechanisms and processes. Several modern po-
lymerization processes (free-radical emulsion,
suspension, and solution, as well as Ziegler-
Natta and metallocene-catalyzed processes) are
presented to illustrate the fundamental concepts
covered in the initial part of the course. The
experience gained by our interaction with in-
dustry via collaborative research projects and
short courses helps us identify the most relevant










polymerization processes for this section of the course. In
this way, it has been possible to design a course with a strong
industry-oriented component while at the same time main-
taining a high level of scientific and academic content.
The course components consist of bi-weekly assignments,
a mid-term exam, and a final exam. Graduate students are
also required to work on a project, results from which are
presented orally at the end of the course. Table 6 shows a
selective list of required and supplementary references for
the course. In addition to these references, several technical
articles describing the state-of-the-art in polymerization re-
action engineering are given to the students as recommended
reading throughout the course.
In order to familiarize students with the vast amount of
literature available in polymer science and engineering, on-
line literature searches are also conducted during the course
in collaboration with our library personnel. Computer simu-
lation case studies in polymerization reaction engineering
are also done using WATPOLY, a user-friendly package
developed at Waterloo for the dynamic simulation of solu-
tion, emulsion, and suspension polymerization reactors. In
this way, several complex aspects of
these polymerization systems can be
examined by the students without
the need of tedious and time-con-
suming calculations. Allcock and Lampe Co
Additionally, the course is comple- Bicerano Prediction ofa
mented with a tour to the polymer- Billingham Molar Mas
ization pilot plant facilities of the de- Billmeyer Textbook of
apartment and with site visits to poly- Brandrup and Immergut
Brandrup and Immergut
mer manufacturing and processing
Several authors Compr
companies in the region.
Dotson, Galvan, Laurenc
Samples of polymer reaction engi- Elias Macromolecules,
Elas Macromolecules,
neering-related problems (tests or as-
Flory Principles of Poll
signments) that have arisen from our ry Priiles o
industrial interactions are presented Grulkey Polymer Proce
in Table 7. Some of these problems Gupta and Kumar Reac
are open-ended and may have mul- *Ham Vinyl Polymerizat
tiple solutions. They are an extremely Hiemenz Polymer Cheti
powerful vehicle in giving the stu- McCrum, Buckley, Buck
dents a flavor of "real-world poly- Moad and Solomon Tlu
mer production" problems. Odian p Principles ofPol

SENIOR-YEAR Peebles Molecular Wei
DESIGN/RESEARCH Rabek Experimental Mi
PROJECTS Rempp and Merrill Pol'
Rodriguez Principles of
All fourth-year undergraduate stu-
dents have to complete either an in- *Rosen Fundamental Pr
dividual research or design project or Rudin The Elements of
a group process design project in di- Saunders Organic Polym
rect collaboration with one faculty Sperling Introduction tc
member. Several Canadian and van Krevelen Propertie
American companies sponsor these
66


projects. Our interaction with polymer manufacturing com-
panies has been beneficial in defining polymer-related re-
search and design projects. Some of these projects are de-
scribed in Table 8.

CLOSING REMARKS
University-industry interaction via industrial short courses
and collaborative research projects can bring several advan-
tages to both academic and industrial participants. As a
result of our own experience with short courses, we have
been able to design academic courses with a high content
of industrially relevant material. Instead of jeopardizing
the academic and fundamental content of these under-
graduate and graduate courses, this approach has actually
stimulated the students to better understand the mecha-
nistic and fundamental aspects of polymerization pro-
cesses that have prominent application in both academia
and industry.
On the other hand, industrial short courses that bring re-
cent fundamental scientific advances to industrial applica-
tions have helped clarify or show different solution alterna-


TABLE 6
Textbook and Supplementary Reading

ntemporary Polymer Chemistry, 2nd ed. Prentice Hall (1990)
Polymer Properties Marcel Dekker (1993)
s Measurements in Polymer Science Kogan Page Ltd. (1977)
Polymer Science Interscience (1984)
* Polymer Handbook John Wiley & Sons (1975)
rehensive Polymer Science, 7 volumes Pergamon Press (1988)
e, and Tirrell Polymerization Process Modeling VCH Publishers (1996)
2 volumes Plenum Press (1984)
vmer Chemistry Cornell University Press (1953)
ss Engineering Prentice Hall (1994)
tion Engineering of Step Growth Polymerization Plenum Press (1987)
ion Marcel Dekker (1967)
nistry: The Basic Concepts Marcel Dekker (1984)
nall Principles of Polymer Engineering Oxford University Press (1988)
e Chemistry of Free Radical Polymerization Pergamon Press (1995)
Yymerization, 3rd ed. McGraw-Hill (1991)
ght Distribution in Polymers Interscience (1971)
methods in Polymer Chemistry John Wiley & Sons (1980)
rmner Synthesis Huthig/Wepf Verlag (1986)
Polymer Science McGraw-Hill (1970)
inciples of Polymeric Materials John Wiley & Sons (1993)
Polymer Science and Engineering Academic Press (1982)
mer Chemistry Chapman and Hall (1988)
Physical Polymer Science, 2nd ed. John Wiley & Sons (1992)
s of Polymers Elsevier (1990)

Chemical Engineering Education












TABLE 7
Polymer Reaction Engineering Problems
Assignments and Exams

PROBLEM 1: Given the following data, calculate (at 0 and 50% conversion): (a) the instantaneous number average chain length of the polymer,
and (b) the average lifetime of a growing chain. Neglect chain transfer and assume that termination is by disproportionation only.
DATA: k= 900 L/mol.s: k2 /kt = 2.314 L/mol.s: k= 3 x 0s': = 0.017 mol/L: M,,= 1.5 mol/L: pM = 0.91 g/cm

PROBLEM 2: MMA is being polymerized in solution in a batch reactor using AIBN as initiator. The solvent is ethyl acetate and the contents are
maintained at 60C. The reactor is initially charged with 75% by volume MMA, 25% by volume ethyl acetate, and enough initiator to achieve
10=0.05 mol/L. Compute and plot (a) rate of polymerization, (b) heat of polymerization. and (c) number average molecular weight as a function
of polymerization time.
DATA: Kp= 170 L/mol.s; k,,= 1.85 x 106 L/mol.s; k,= 7.5 x 106 s'; k,/k,= 0.00014; pM = 0.91 g/cm'; p, = 0.85 g/cm1; f= 0.5

PROBLEM 3: Redo Problem 2 using the following gel-effect functionality for the termination rate constant: k =k, for x < 0.36; k =
0.1296(k/x') for x > 0.36.

PROBLEM 4: Find the reactor volume, total flow rates, and average residence time to produce 10.000 ton/year of styrene-acrylonitrile bulk
copolymer containing 28% (mole) acrylonitrile (365 days/year, 24 hours/day). If you need to make assumptions, state them clearly and justify
them. Assume that the total conversion in 60%.
DATA: r,= 0.41; r,= 0.04; k,,= 176 L/mol.s: k,_= 2500 L/mol.s; k= 5 x 10' L/mol.s: p, = 0.903 g/cm: p, = 0.811 g/cm'; R,= 107
mol/L.s; M, = 104 g/mol; M,= 53 g/mol. (l=styrene, 2=acrylonitrile)

PROBLEM 5: Consider a CSTR free-radical polymerization operating at steady state. Using the following data, map out the possibilities for
steady-state conversion versus residence time. How would you achieve 75% conversion? For results uniformity, consider a reactor operation of
365 days/year and 24 hours/day.
DATA: I = 1,,= 0.017 mol/L; M,,= 1.5 mol/L; k,,= 3.5 x 10' L/mol.s; kd= 3 x 10 s '; kp = 900 L/mol.s; f = 1
k=kforx<0.2 and k= (kJ0.512)(1-x) for x >0.2
kp= kp, for x 0.85 and k = (k1/0.0225)(l-x) for x > 0.85

PROBLEM 6: An isothermal polymerization is carried out at 100'C with a dual initiator system. After three hours of polymerization, the
monomer conversion is 60% in a 40,000-liter batch reactor. (a) Calculate the total radical concentration at 60% conversion of monomer (k,=10'
L/mol.s); (b) How long does it take to grow a polymer chain of molecular weight equal to 105 at 60% conversion? (c) Find the instantaneous
heat generation rate at 60% conversion. Compare this with the value at zero conversion: (d) Calculate instantaneous M and M at 0% and 60%
conversion; (e) The growth in M at high concentrations gives too broad a MWD. The solution is to use a chain transfer agent (CTA). Find the
amount of CTA required to keep M, almost constant over the conversion interval 0-60% given that k,= 100 L/mol.s. Compare M values at 0%
conversion for cases with and without CTA.

DATA: I0= 2 x 10 mol/L; I,,,= 5 x 10' mol/L; MW= 100 g/mol: (-AHp) = 17 kcal/mol; ktd(= 107 L/mol.s: k l= 10 s ; k,,= 10s-';
M,= 10 mol/L; k, =0: kp= 101 L/mol.




TABLE 8 tives to several problems encountered in industry. The ques-
SL 8e tions raised during these short courses have resulted several
Some Senior-Year Design/Research Projects
times in new research projects at both the undergraduate and
Dynamic simulation of ethylene-propylene impact copolymers in a the graduate level. In the process of attempting to tackle
series of CSTRs these industrially related problems, novel fundamental knowl-
Copolymerization kinetics of methyl methacrylate/vinyl acetate edge is generated, pushing the boundaries of our knowledge
Terpolymerization kinetics of methyl methacrylate/vinyl acetate/ in polymer science and engineering even further.
butyl acrylate NOTE
Investigation of kinetics of a -methyl styrene/methyl methacrylate at
elevated temperatures As a point of information for the academic readers of this
Investigation of butyl acrylate homopolymerization at high article, we are planning a series of short courses to assist
conversions chemical engineering academics who are teaching, or wish
Modeling of suspension polyvinyl chloride reactors to teach, polymer-related courses at the undergraduate level.
Educational uses of a general polymerization simulator package We welcome all communications from interested academics
Injection molding of medical plastics who would like to either attend these short courses or to give
Gel content in polyethylene/polypropylene sheets lectures on undergraduate courses in the polymer area that
they have successfully given. 7
Winter 1998 67










I classroom


PRACTICAL TIPS FOR


GATHERING INFORMATION




SAIDAS M. RANADE
Consultant Houston, TX 77079-2995


Engineers working in process plants are problem-
solvers. They play a very important role in process-
plant troubleshooting. For example, consider the
following situation:
The quality of a product from a certain unit has been de-
grading for some time and for some "unknown" reason.
You are a plant support engineer and you have been called
upon to help. Your job is to identify the root cause, to
quantify the business benefits of solving the problem, and
then to suggest ways to eliminate the factors causing the
problem.
What is problem-solving, and how does it begin? The verb
"solve" comes from the root solvere, which means "to loosen,
release, or set free." The word "problem" comes from the
roots pro, meaning "forward," and ballein, meaning to "throw
or drive." So, problem-solving is a process of proposing and
considering questions in a way that throws or drives us
forward toward greater freedom.[
In their entertaining book, The Universal Traveler, Don
Koberg and Jim Bagnall define the seven stages of creative
problem solving as "acceptance, analysis, definition, ide-
ation, idea-selection, implementation, and evaluation."121
Clearly, being aware of a problem's existence is the first
step. Gathering information about the situation is the next
step. One can learn about the situation through literature and
document searches, by direct observation, and by gathering
information from people closest to the problem. This skill of
gathering data from others is a critical success factor for all
practicing engineers. Whereas gathering information from
literature and the Internet is emphasized in most engineering
courses, to the best of my knowledge, training in how to
gather information from others is not offered.
The main objective of this article is to share some practical
ideas on improving the speed and effectiveness of the pro-
cess of gathering information from others. It is based on my
experience in designing and conducting opportunity and sup-
port needs assessment surveys for process modeling in pro-


cess plants. Although the article will focus on techniques for
more organized information gathering (such as surveys and
on-site visits), the principles illustrated are equally appli-
cable to informal information exchanges. This domain of
designing and conducting surveys has been developed ex-
tensively by social scientists. I will begin first by defining
the prerequisites for effective information exchange and
then I will provide specific guidelines on how to pose the
right questions. The article will also include a brief dis-
cussion on how one might be able to use this information
in a classroom setting.

KEY PREREQUISITES
Early in my career, I learned that communication consists
of a message, a sender, a receiver, a medium, a context,
feedback, and noise.[3,4] For gathering information, the mes-
sage is the "questions," and the medium may be a printed
survey or a face-to-face interview (i.e., spoken words). I
have discovered five key prerequisites necessary for cre-
ating the right context, capturing the feedback, and mini-
mizing noise.
Trust This is the first prerequisite. Thanks to authors
such as Peter Senge[51 and Stephen Covey,16' discussions on
trust and trusting are becoming more acceptable, even among
hard-core engineers. Trust is the foundation of all effective
communication. The survey recipients must clearly under-
stand the purpose of the information exchange. They must
know "why" the information is being requested and "how"

Saidas M. Ranade PhD, PE, was the Principal
Consultant for Aspen Technology, Inc.'s Model-
ing Success Program. Some of the tools he
has developed and applied to ensure that cus-
tomers get the best value from AspenTech's
modeling technologies and services include
modeling opportunity assessments, modeling
needs assessment, a template for documenting
successes, and a method for cataloging pro-
cess models. He can be reached at
smranade@neosoft.com.


Copyright ChE Division ofASEE 1998


Chemical Engineering Education










their information will be used.17'81 It is the
interviewer's obligation to pursue the truth The ma
and truly believe in doing everything to ben- of this
efit the interviewees. Of course, trust can- to sht
not be mandated, and there are no shortcuts practice
to building trust. Vendors of software and improving
associated services have the challenging task effective
of overcoming a history of "lack of trust" process
created by their industry-for example, cus- inform
tomers do not believe in software release others..
dates. Also, in dealing with process manu- the ar
facturing plants, the issue of confidentiality focus on
of information is very important and must for mor
be explicitly addressed prior to any useful informati
information-gathering session. (such
Credibility and Respect The second and on-
prerequisite to effective information-gath- the princip
ering is the interviewer's credibility in the are equal
domain of the specific inquiry. People are to ii
more open to answering your questions if infoi
you have already established a track record, excJ
either with the site or the process or the
field of inquiry (i.e., if they respect you). There are pros and
cons to this phenomenon. You may be very talented and may
have a novel approach to solving problems; but you may not
be effective simply because you are new. Also, due to this
emphasis on "credibility," it is very tempting to use the
jargon of the business superficially to establish credibil-
ity, but experience has shown me that instead of attempt-
ing to appear knowledgeable, it is better to admit that
you are new to the field.
Effective Listening This is the third prerequisite. Hon-
est and open exchange of ideas is possible only when you
have a genuine interest in the views and opinions of the
interviewees. One of the best definitions of effective listen-
ing comes from Dr. Stephen Covey. He equates effective
listening to faithful translation. The main requirement to
having a dialogue and not just a discussion is to be com-
pletely open to the outcome. This is at the heart of any true
discovery process. The word "dialogue" comes from two
Greek roots: dia, meaning "through," and logos, meaning
"the word." It carries a sense of "meaning flowing through."
The word "discussion," on the other hand, stems from the
Latin discutere, which means "to smash to pieces." Addi-
tional useful information on the topics of "Inquiry" and "The
Art and Practice of Conversation" is presented in Ref. 5.
Proper Timing and Setting This is the fourth prerequi-
site. One of the biggest challenges for engineers and opera-
tors in process plants is to make time available for surveys
and audits. Hence, the surveys must be aesthetically de-
signed and the participants should be given ample time to
complete them. In a face-to-face information-gathering ses-
sion, the room in which interviews are conducted should be


in ol
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ire s
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the
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of ga
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Winter 1998


comfortable and open, with several
jective whiteboards and easels. During a scheduled
cle is plant turnaround, a plant is typically shut
some down for several weeks. This period is used
eas on to make major modifications to the process
speed and and to install new plant equipment. Many of
s of the these new items have to be ordered six to
withering nine months in advance, and it takes about
n from three to six months to develop detailed speci-
lthough fications for major items. So the best time to
will conduct opportunity assessments is about
hniques nine to fifteen months prior to a scheduled
:anized turnaround. In this manner, the recommended
gathering revamp-type projects can be implemented
rrveys during the turnaround period.
visits), Gratitude This is the fifth prerequisite.
illustrated It helps immensely if your demeanor con-
pplicable veys a genuine sense of gratitude toward
nal those from whom you collect information.
tion In today's atmosphere, it seems that
:es. everyone's agenda is full all the time, so
even if you do not find some of the responses
to be useful, it always makes sense to thank the interviewees
or survey participants for their time. It is also important to
publicly acknowledge any contribution made by others to
the success of your projects.

GUIDELINES FOR POSING QUESTIONS[7-9]
After having satisfied the above prerequisites, one may
still not be effective in conducting surveys and on-site inter-
views. This is where the "science" of asking questions comes
into play. The following quotes and events signify the im-
portance of questions and questioning:
D "You can tell whether a man is clever by his answers. You
can tell whether a man is wise by his questions."
Naguib Mahfouz
Winner, Nobel Prize for literature, 1988[11
When Richard Feynman was a child, his Mother asked the
future Nobel Prize winner the same question every evening
at the dinner table: "What did you ask at school today,
Richard?" (Feynman won the Nobel Prize for physics in
1965.) 1
> Hammurabi of Babylon changed the course of history by
changing the representation when dealing with the prob-
lem of an inadequate water supply. Instead of asking how
to get the people to the water, he asked how to get the
water to the people. This led to the invention of canals."101

Creation of the proper context is necessary for both printed
surveys and on-site interviews. In a printed survey, the con-
tent and the order of the questions must be carefully se-
lected. In a face-to-face interview, in addition to the choice
of words and their sequence, proper tone of your voice plays
a very important role.










I will begin with a brief discussion of different types of
questions. Then I will provide guidelines on wording of
questions and maintaining a flow for the on-site interviews.
Types of Questions
In his book Just So Stories (1902), Rudyard Kipling (who
won a Nobel Prize for literature in 1907) had this to say
about types of questions: "I keep six honest serving men.
They taught me all I know. Their names are What and Why
and When and How and Where and Who." The "how"-type
question is the most open-ended. The "why"-type question
may put the interviewee on the defensive. At some point in
time, the questions beginning with "why" are essential to
finding the cause of the problem; initially they may not be
very effective, however.
Yet another method of classification also results in six
types of questions. They are questions pertaining to experi-
ence/behavior, opinions/values, knowledge, feeling, sensory,
and background (or demographics)."91 For each type of ques-
tion, one can ask about the present, the past, or the future.
Questions pertaining to experience or behavior or actions
are easy to answer and should be used first. Sensory- and
background-type questions are mundane and should be dealt
with toward the end of the on-site interview. Questions
pertaining to participants' opinions/values and knowledge
are very important for identifying symptoms and causes of
problems, but they require proper context-building prior to
their use. It is important to gauge the level of an individual's
knowledge about a given situation without making it seem
that you are testing him. Engineers, in general, tend to shy
away from "feelings"-type questions and, hence, they should
be kept to a minimum.
For the time-frame, it is always appropriate to start from
the present and then move to the past and then to the future.

GUIDELINES ON PROPER WORDING[1[89]
Basics First, ask truly open-ended questions. "How
satisfied are you with the performance of this heat ex-
changer?" may seem like an open-ended question, but it is
not. Second, it is important to ask a "singular" question (i.e.,
refer to only one idea per question). A good question should
be relatively short, clear, and unambiguous. Do not run a
string of questions together. If you want to ask a string of
related questions, then ask one at a time and get a response
before proceeding.1"" The question, "How often do you mea-
sure the pressure drop across this exchanger, how good are
the measurements, and do you know the cause of the
sudden increase in the pressure drop?" should be split up
into three separate questions.
The third basic rule is to use the terminology and language
of the interviewee or survey-recipient. Be careful of acro-
nyms such as QIT, BIP, PIP, etc., because they may have
different meanings at different plants. If you do choose to


use acronyms, it is always beneficial to define them.
A Few No-No's In the beginning, avoid questions that
result in "yes" or "no" responses. The whole idea is to get
the participants to "open up." Also, avoid "why" questions
in the beginning. From our childhood, we have been condi-
tioned to associate some type of blame with the word "why."
("Why" did you break this vase?) The objective of gather-
ing information from others is accomplished when you
make them feel comfortable about the situation and encour-
age them to have a dialogue with you.
Proven Techniques Presupposition-type questions are
good. For example, "What is your most important idea
regarding the cause of fouling?" This question presupposes
that the interviewee is capable of having several good ideas
about the cause of the problem. Questions pertaining to
tough topics or questions that seem too direct can be soft-
ened considerably either by role playing (i.e., putting your-
self in a new role in the question) or by simulation (i.e.,
putting the interviewee in a new role in the question). Rather
than asking, "What do you do in the plant in the morn-
ing?" ask, "If I were your colleague accompanying you
in the plant, what would I observe?" And, instead of
asking a unit engineer, "What are the goals of the entire
plant?" try, "If you were the plant manager, what would
be your top priorities?"
Keeping the Flow It is very important to keep the on-
site interviews flowing smoothly. This depends on several
factors. Establishing rapport with the individual and main-
taining neutrality toward the information they provide are
very important steps for keeping the flow. It always helps to
make transitions smooth rather than abrupt by making spe-
cific announcements before the transitions. Prefatory state-
ments such as, "The next question may seem a bit vague,"
are very useful to ensure that the interviewee is not under
undue pressure to look for a precise answer. Elaboration,
clarification, and contrast-type probes are very useful in
getting some individuals to talk. Of course, thanking the
interviewee for providing a response to a tough question is
also effective in keeping the flow of the process. In general,
it is very hard to get engineers to converse openly with you,
but occasionally you will come across individuals who try
to monopolize the conversation and will not stop talking.
In such cases, it is important to emphasize, in a conver-
sational tone of voice, that everyone's time is important.
The flow of the process can be easily disrupted by long-
winded or irrelevant comments.

CLASSROOM APPLICATION OF THIS MATERIAL
One easy way to make students aware of the issues in-
volved in gathering information from others is to ask stu-
dents to read this article and spend about an hour discussing
the topic in the classroom. As an additional homework
assignment, you may ask students to watch the 1996 Twen-
Chemical Engineering Education










tieth Century-Fox movie, Courage Under Fire, which clearly
demonstrates that the same event (or a problem) can be
perceived very differently by different people. Since the
right psychology and information may not exist readily in
most chemical engineering classrooms, the only way to di-
rectly practice the techniques prescribed in this article is by
simulating a few real-life situations in a classroom setting
and requesting students to play specific roles. One such
approach, which requires a fair bit of preparatory work, is
described in the Apppendix.

CONCLUSION
Engineers and managers are problem solvers. An impor-
tant step in identifying and defining problems involves gath-
ering data. Since every situation is unique, it always helps to
gather information about a situation from the people who are
closest to it. The techniques for gathering information
from others are very important for process-plant trouble-
shooting and are not emphasized enough in formal chemi-
cal engineering education.
The main point is that one will be able to easily acquire
useful information from others by ensuring that the prerequi-
sites such as trust, respect, effective listening, proper timing,
and gratitude are met and following the guidelines for cor-
rect wording, sequence, and tone of the questions. Practic-
ing the techniques without the prerequisites is possible,
but only results in manipulation and deception and should
be avoided at all costs.

ACKNOWLEDGMENT
The opinions expressed or implied are those of the author
and do not represent the views of AspenTech.

REFERENCES
1. Gelb, M.T., Thinking for a Change, Harmony Books, New
York, NY, 96 (1995)
2. Koberg, D., and J. Bagnall, The Universal Traveler, Crisp
Publications, Inc., Los Altos, CA, 41 (1991)
3. Wurman, R.S., Follow the Yellow Brick Road, Bantam Books,
New York, NY, 17 (1992)
4. Salsbury, G.B., A Resource Manual For Effective Presenta-
tions, Salsbury Communications, Inc., Manhattan Beach,
CA (1985)
5. Senge, P.M., et. al., The Fifth Discipline Fieldbook, Cur-
rency-Doubleday, New York, NY (1994)
6. Covey, S.R., Principle-Centered Leadership, Fireside, New
York, NY (1992)
7. Salant, P., and D.A. Dillman, How to Conduct Your Own
Survey, John Wiley & Sons, Inc., New York, NY (1994)
8. Sudman, S., and N.M. Bradburn, Asking Questions: A Prac-
tical Quide to Questionnaire Design, Josey-Bass, Inc., San
Francisco, CA (1982)
9. Patton, M.Q., Qualitative Evaluation and Research Meth-
ods, 2nd ed., Sage Publications, Newbury Park, CA (1990)
10. Rubenstein, M.F., and I.R. Firstenberg, "Tools for Think-
ing," in Developing Critical Thinking and Problem-Solving
Abilities, Ed., Stice, J.E., Josey-Bass, Inc., San Francisco,
CA (1987)

Winter 1998


11. Wankat, P.C., and F.S. Oreovicz, Teaching Engineering,
McGraw-Hill, Inc., New York, NY, 101 (1993)
12. Lieberman, N.P., Troubleshooting Process Operations, 3rd
ed., PennWell Books, Tulsa, OK (1991)
13. Saletan, D., Creative Troubleshooting in the Chemical Pro-
cess Industries, Chapman & Hall, New York, NY (1994)


APPENDIX
An Experiment for Testing the Ideas
in a Classroom Setting

Preparation At the beginning of the experiment,
divide the students into groups of five. Provide each
group with a handout or script describing a specific
situation. Examples of such situations include safety
incidents, environmental excursions, product quality
problems, etc. You may use the published case studies
from books, such as those by Lieberman,"121 Saletan,1'31
etc., to create the specific scenarios. On each team,
assign one of the following roles to each student
Operator
Plant Engineer
Tech-Support Engineer from a Central Group
Plant Manager
Chemist
Assignment To identify, define, and solve problems
faced by all the other teams.
Rules Give students about four weeks to complete
the assignment. Request that the students
Not reveal the actual script or handout to
anyone outside of their team
Play the assigned roles as faithfully as possible
Only answer the questions being asked while
remembering the mindset of the role they are
playing
Document their strategy for gathering the
required information
Document their feelings, thoughts, and any
other reactions to the mode of inquiry used by
each of the other teams.
Criteria for Grading
Number of problems identified
Number of problems solved
Nature of the means used to obtain information
Impact on the feelings of others during the pro-
cess of gathering information
Quality of the document describing the strategy
used to acquire information
Quality of the document describing the feelings
and thoughts during the inquiry by other teams.
0










looking back


ADVICE FROM AN OLD-TIMER



W. DAN MACLEAN
Pinnacle Technology, Inc. e Lawrence, KS 66044


Process engineers, such as myself, who are approach-
ing retirement or are at an age where "you can see it
from here," probably received their undergraduate
training in the 1950s. As we consider the prospect of
retirement, or edge into it through part-time work or
consulting jobs, it is interesting to consider how we dif-
fer from today's graduate.
There is little question that today's graduate is better
equipped with the "tools of the trade" and better prepared to
be immediately useful. But it can be argued that my genera-
tion spent an apprenticeship doing hand calculations that
were more productive. For example, hours, if not days, were
spent checking a heat exchanger design by hand, giving us a
better feel for the variables involved than doing computer
iterations would. But time soon evens everything out.
So, what can my generation pass on to new process engi-
neers? Perhaps some rules-of-thumb that have been useful,
or some guidelines for good practice, or some judgmental
discernments that we have learned through unfortunate ex-
periences. What follows are some of the rules and guidelines
that have proven useful to me over the years.

STREAM EFFICIENCY
The stream efficiency, or annual on-stream operating time,
is a key factor in successfully operating any chemical plant.
Plants are designed to run on gallons per minute, or pounds
per day, or barrels per stream day. But cash is generated and
investors are rewarded from tons per annum, or pounds per
year, or barrels per calendar day.
A key number to remember is 8760-the number of hours
in a year. In a perfect world that is error and maintenance
free, a plant would produce in a year 8760 times what it
could produce in an hour. But allowing for a two-week
annual maintenance shutdown and an unscheduled outage of
one day a month, the operating hours in a year are actually
8136, for a stream efficiency of 93%.
In actual practice, a promise of more than 8000 operating
hours in a year (or a stream efficiency of 91%) is highly
suspect. Oil refineries that are well run and well maintained


show that stream efficiencies in the 90s are difficult to achieve.
The refining industry as a whole probably operates with a
stream efficiency in the mid-to-high 80s.
Projected high stream efficiencies often stem from mas-
saging the numbers to improve a project's economics, and
"name plate" capacities are probably derived from a 72-hour
test run, or whatever was contractually agreed upon at the
beginning. Remember, though, that the real test run is the
8000-hour test. One should use 8000 operating hours per
year as the goal, even when giving appropriate consider-
ation to feed outages, power interruptions, changing prod-
uct grades, etc.

ECONOMIC ANALYSES:
TOP LINE VS. BOTTOM LINE
There are many excellent guides to preparing economic
projections for a new project. For the most part, these
guides focus on developing the "bottom line," i.e., net
profit, cash flow, payback, etc. That is what owners and
investors want to see.
Much useful information, however, can be obtained from
an analysis of the "top line," i.e., the total sales generated.
One should look at sales generated per dollar invested in
much the same way as stock analysts look at a company's
sales-per-share. How many times per year the sales "turn
over" the capital invested can lead to a good appreciation of
a project's risks and rewards.
Assume annual sales per invested dollar are substantially
greater than one; unless the project is the proverbial license


Dan Maclean graduated from the University
of Toronto with a BASc in chemical engineer-
ing in 1954, and received his MASc in chemi-
cal engineering from Birmingham University
(United Kingdom) in 1959. He worked for
Celanese Corporation and for several oil refin-
eries during his career, and since 1984 has
had a wide range of consulting assignments,
usually in the area of alternative fuels such as
alcohol/gasoline blends and pyrolysis oils.


Copyright ChE Division ofASEE 1998


Chemical Engineering Education










to print money, the margin per sales dollar is going to be
thin. Examine the margin carefully. How firm is it? A small
reduction in the margin could eliminate any profit. Is the
operation a value-added one, such as refining crude oil where
the margin is protected by a direct link between raw material
and product prices? If a large volume of raw materials and
products is involved, has sufficient attention been paid to
materials-handling factors? Concentrate on the cost factors
involved in the project.

HEAT EXCHANGERS
Without question, the most common mistake made in speci-
fying heat exchangers is made by the conservative engineer
anxious to supply adequate equipment who specifies too
much area! By a unit that is too big, fluid velocities are
reduced to less that 3 feet/second, transfer coefficients fall,
and deposits build up in stagnant zones. Performance is poor
and even, in some cases, inadequate.
Three feet/second is the absolute minimum velocity,
shell or tube side, that should be considered. Providing
the head required is a small price to pay for good heat
exchanger operation.
A rapid way to estimate the number of tubes in a shell and
tube exchanger is with the formula
N = C(L/P)2
where
N = number of tubes
P = tube spacing, inches
L = "outer tube limit," inches
C = constant, 0.75 for square pitch, 0.86 for triangular pitch
The "outer tube limit" is 5/8 in. less than the shell diameter
for fixed tube sheet or U-tube construction, and 1 1/2 in. less
for floating head construction.
Assume 20-inch nominal shell diameter (19.2-inch inside
diameter)
16-ft tube length, fixed tube sheet, 3/4-inch tubes
on I-inch square pitch
N = 0.75 (18.575/1)2 = 259 tubes
Area = (259)(16)(0.196) = 812 sq. ft.
or assume As above, but with 1-inch tubes on 1 1/4-inch
triangular pitch
N = 0.86 (18.575/1.25)2 = 190 tubes
Area = (190)(16)(0.262) = 796 sq. ft.
This formula neglects tubes lost due to multipass construc-
tion, impingement plates, etc.

PUMPS
The old adage, "All pump problems are suction prob-
lems," still applies. Design for low velocities in suction
lines: 0.5 to 1 foot/second for boiling liquids, and 1 to 3 feet/
second for non-boiling liquids.
Vortex breakers are often omitted or ignored. Cross or flat


There is little question that
today's graduate is better equipped
with the "tools of the trade" and better
prepared to be immediately useful. But it
can be argued that my generation spent an
apprenticeship doing hand calculations
that were more productive.


plate baffles, with a width of 2 to 4 times the nozzle
diameter and a height of one-half the nozzle diameter are
effective vortex breakers.

PLOTS AND COUNTERPLOTS
A company I once worked for operated some acetylation
kettles in which sheets of cellulose (wood pulp) were acety-
lated with acetic anhydride. The kettles were jacketed with a
recirculating brine to remove the heat of reaction. Brine
circulation was controlled manually to prevent rising tem-
peratures from degrading the cellulose and falling tempera-
tures from reducing the reaction rate.
Varying temperatures, humidities, and time in storage of
the cellulose resulted in varying moisture levels in the cellu-
lose. This resulted in varying reaction temperatures and the
recurring question-were we over- or under-controlling?
Were we looking at random noise when the temperature
wandered, or had reaction conditions actually changed?
Routinely, we plotted kettle temperatures to see to what
extent we were diverging from set point. Next, we initiated a
new plot for every five minutes, showing the cumulative
extent to which temperature diverged from the set point. If
the temperature was cycling randomly around the set point,
this second curve would make an exaggerated cycle but
would return to zero (see Figure 1).
If, however, reaction conditions had changed and a new
equilibrium temperature had been established, the second
plot would rapidly indicate this by going outside any bound-


TEMTPERTURE
TIME






CLMULATIVE
DEVIATION
FROM
SET POINT o '
TIME



Figure 1


Winter 1998












NEW EQUILIBRIUM TEMPERATURE













DVIA1IUN FROM
SFT POINT o )
TIME


Figure 2

ary limits (see Figure 2). Boundary limits can be readily set
after some operating experience.

The same kind of plot can be useful in any situation where
you want to establish if a status quo situation or an existing
trend line had been breached. They can be used alongside
moving average plots in financial quotations.

Another plot I have found useful is the probability paper,
both normal and logarithmic. A probability paper is most
suited to record a series of events distributed around a mean
where one wants to design for a certain fraction of the
occurrence of the events. These events could be temperature


I TABLE 1


Daily Truck Loadings

#of Day number
Trucks "M"
Loaded
60 1
40 2
85 3
30 4
67 5
46 6
60 7
42 8
90 9
51 10
53 11
62 12
34 13
73 14
80 15
50 16
38 17
28 18
40 19
45 20(N)

53.7 Avg.


Daily Truck Loading
in Ascending Order

# of Trucks
Loaded, [M/(N+1)]
in order
28 0.048
30 0.095
34 0.143
38 0.190
40 0.238
40 0.286
42 0.333
45 0.381
46 0.429
50 0.476
51 0.524
53 0.571
60 0.619
60 0.667
62 0.714
67 0.762
73 0.810
80 0.857
85 0.905
90 0.952


Figure 3

or wind levels, ship arrivals, river flows, etc. As an example,
consider daily truck loadings at a terminal. The number of
trucks per day is tabulated by day "M" in Table 1. Next,
arrange them in ascending order and divide "M" by (N+1),
where N is the total number of days, and plot "M"/(N+1) vs
the number of trucks/day, or probability paper. The data
aligns reasonably well (see Figure 3).

To satisfy the loading demanded four days out of five, or
80% of the time, inventory would be required to fill 70
trucks. If it was desired to satisfy the loading demanded nine
days out of ten, inventory would be required to fill 85 trucks.

LINE SIZING

The guideline "1 pound per 100 feet" pressure drop can
serve to size lines in a wide variety of situations. The tables
in "Cameron Hydraulic Data," based on the Williams and
Hazen formula, form a conservative standard. Two points
worth mentioning here are:

1) In long, large-diameter lines, hold the velocity down to a
walking pace of 4-5 miles per hour, or 6-7 feet per second.

2) 1 1/2-in. sch. 40 pipe is the smallest size that will span 15-
to-20-foot pipe racks without intermediate support. Opera-
tors often climb on piping to take readings, etc., so 1 1/2-in.
pipe is the smallest pipe size that should be used for routine
use.


These are some of the guidelines and rules-of-thumb that
have been of value to me during my career. Perhaps this
article will prompt other "senior" process engineers to share
some of the experience they have gained during their ca-
reers. We seniors owe a lot to a profession that has rewarded
us well, both personally and professionally. O


Chemical Engineering Education


99.99-

99.9 -
99.5 .
99
98 -
91
90
S 80
7 60 -4
40 -
20

1 0

0.
o.1
0.02

0 20 40 60 0O 00
DAILY TRUCK LOADINGS










BOOK REVIEW: Introduction to Theoretical and Computational Fluid Dynamics
Continued from page 29.


emphasis of the book is strictly on fundamentals, particu-
larly the general mathematical description of fluid motions
and the presentation of solutions for important fundamental
flow problems. The exposition is relatively abstract; little
reference is made to applications, to experiments, or to ob-
servations of natural phenomena. In general, solutions to
posed problems are obtained or outlined through exact ana-
lytical and numerical methods, primarily via singularity ap-
proaches or finite difference methods. This book contains a
vast amount of detailed information, from the differential
geometry of general surfaces in flow fields to the similarity
solutions for Stokes flow near covers to the subtleties of the
stability problem for inviscid shear flow.
The book begins with two excellent chapters on the kine-
matics of flows; of particular note are explicit general for-
mulas for surface mean curvature and a collection of veloc-
ity fields determined by various vorticity distributions. The
next chapter introduces stress and the equation of motion;
nice features include a concise exposition of constitutive
equations and a good discussion of vorticity transport; vor-
ticity is a theme that receives a great deal of emphasis
throughout the book. A brief chapter on hydrostatics fol-
lows, including many examples of the computation of static
free surface shapes. Curiously, mean curvature is defined
again, with no reference to Chapter 1.
Chapter 5 presents many of the classical exact solutions
for viscous incompressible flow, including unidirectional
flows, Jeffery-Hamel flow, stagnation point flows, and flows
due to point sources.
Flow at low Reynolds numbers is the topic of Chapter 6.
The primary emphasis is on singularity solutions of Stokes'
equation, including a sketch of boundary-integral equation
methods. A fairly detailed exposition of local solutions near
covers is also given. Transient flow effects and the first
effects of inertia are touched upon.
Chapters 7 and 8 describe irrotational flow and boundary
layer theory, respectively. For irrotational flow, the basic
results on force and torque exerted on a body in steady or
time-dependent irrotational flow are described. Several
pages are devoted to the use of conformal mapping for
solving the Laplace equation. The chapter on boundary
layers provides good coverage of the classical material.
As in other places though, the author is sometimes overly
terse here.
Chapter 9 is a very nice chapter on hydrodynamic stabil-
ity, containing the basic results for shear flow, free surface,
capillary, and centrifugal instabilities, though perhaps too
brief regarding centrifugal instability. Noteworthy is the dis-
cussion of the concepts of absolute and convective instabil-


ity and their relationship. It would have been nice, however,
to see some generic results about nonlinearity, such as a
brief discussion of supercritical and subcritical bifurcation.
Chapters 10 and 11 focus on the solution of inviscid flow
problems. Chapter 10 outlines the boundary integral equa-
tion approach to the solution of potential flow problems,
while Chapter 11 describes vortex motion in inviscid fluids,
with the goal of providing the framework for numerical
solution of vortex dynamics problems. Chapters 12 and 13
provide a whirlwind tour of finite-difference approaches to
solving convection-diffusion and incompressible flow prob-
lems. One attractive feature of this section is the presentation
of the modified differential equations associated with some
of the approaches, showing, for example, that the instability
of the FTCS scheme for a hyperbolic equation is traceable to
an effective negative numerical diffusivity. Finally, two con-
venient appendices contain basic results in vector calculus
and basic numerical methods.
There is clearly a great deal of material covered here, and
covered well. Nevertheless, the breadth and depth of cover-
age has its cost. The text occasionally becomes an extended
list of formulas, solutions, or methods. This is fantastic as a
reference; I have used it repeatedly myself and referred parts
of it to several graduate students. It is not always ideal for
teaching purpose though, as the means by which solutions
are obtained is often given little motivation. Details of solu-
tion procedures are often not provided, and sometimes op-
portunities to impart physical insight are bypassed in favor
of a terse, elegant, mathematical statement or argument.
The level of mathematical sophistication assumed is at
least that of a first-year grad student in chemical engineer-
ing, preferably one who has already taken an applied math
class covering linear algebra and elementary partial differen-
tial equations. Because of the mathematical level of this
book, the abstract point of view, and the sole emphasis on
fundamentals, it is not appropriate as an undergraduate
text for chemical engineering students. Nevertheless, it
is probably a text that any serious student of fluid dy-
namics would like to own, and it would provide a good
text for either an introductory or advanced graduate course
in fluids, depending on the topics chosen. The lecturer
will need to fill in many of the motivations and solution
details, but this is not a large price to pay for a text that
outlines theoretical fluid dynamics as thoroughly as this
one does.
In my opinion, this is a very important contribution to the
textbook literature in fluid dynamics-a book I am happy to
own and one that I would highly recommend to anyone
working in theoretical fluid dynamics. O


Winter 1998











e= laboratory


AN UNDERGRADUATE


EXPERIMENT ON ADSORPTION


SHAMSUZZAMAN FAROOQ
National University of Singapore Singapore 119260


Adsorption separation has become a major unit op-
eration in the chemical process industry. Under-
graduate chemical engineering students at the
National University of Singapore receive about six hours of
lectures on adsorption fundamentals and applications as part
of the course Separation Processes II, offered in the third
year of their study.
We have long felt there is a need for a suitable laboratory
experiment that reinforces the basic design concepts. Since
reliable equilibrium and mass transfer data are central to the
design of an adsorption separation process, we have recently
introduced an experiment in our third-year laboratory in
which the students determine these parameters from break-
through measurements in an adsorption column. During
analysis of the breakthrough data, the students also develop
a basic understanding of adsorption process dynamics.

EXPERIMENTAL APPARATUS
The experimental apparatus for breakthrough measure-
ments, schematically shown in Figure 1, consists of a col-
umn packed with the adsorbent under study and a host of
pressure and flow controllers that control the operating pres-
sure and concentration of the adsorbate in the feed, respec-
tively. Further details on the experimental apparatus and the
adsorbent used are given in Table 1. The adsorbate is nor-
mally mixed with an inert carrier. The effluent stream is
analyzed using a suitable detector to monitor the break-


degrees in chemical engineering from BUET
(Bangladesh) and his PhD from the University of
New Brunswick (Canada). A faculty member in the
Chemical Engineering Department at the National
University of Singapore since 1991, his research
interest is in the area of adsorption gas separation.
He is a coauthor of the book Pressure Swing Ad-
sorption (VCH, 1994).


@ Copyright ChE Division ofASEE 1998


- Bypass line
Pressure gauge
4 On-off valve
1 Mass flow controller


CR


Vent


BPR


Jacketed Adsorption column
Oxygen analyzer
Back pressure regulator
Rotameter
Chart recorder


Figure 1. Schematic diagram of the breakthrough
apparatus. Further details are given in Table 1.

through of the adsorbate. The desorption response is mea-
sured by withdrawing the flow of adsorbate from the feed
after the column has been saturated.

THEORY
A typical breakthrough response from a clean bed to a step
change in adsorbate concentration in the feed is shown in
Figure 2, where c is the concentration at any time, t, and co is
the constant feed concentration. When the adsorbate concen-
tration in the effluent equals that in the feed, it indicates that
the bed has been saturated. Material balance over a saturated
bed gives

mean residence time, t, = (shaded area in Figure 2)

c L 1- +r I e- qo
= 1- 1 dt= -1+
Co Vo E Co
0
where
L length of packed bed
Vo interstitial feed velocity
Chemical Engineering Education












e bed voidage
qo equilibrium adsorbed amount corresponding to feed con-
centration, c.

A typical favorable equilibrium isotherm is shown in Figure
3. Henry's constant will be measured in this study, which
requires that the experiments are conducted in the linear
(low concentration) range of the isotherm. Ratio of Henry's
constants of two adsorbable components is the primary mea-
sure of their separability.

It is important to note that here Henry's constant is dimen-
sionless, since it has been expressed as concentration ratios.
Henry's constant follows the Arrhenius Law of temperature
dependence. The following equation is applicable for di-
mensionless Henry's constant:

-AU0
K= Ke RT
where

Ko pre-exponential factor
Rg gas constant in heat units
T temperatures in absolute units

A semilogarithmic plot of K vs. 1/T should give a straight
line with -AUo /Rg as the slope and Ko as the intercept. The
change of internal energy due to adsorption, AUo, is related


c/co dC/C

0 t t

Adsorption column
Feed Effluent
v, cm/s c moles/cc
Co moles/cc


Figure 2. A typical breakthrough response for a step
change in feed concentration.




Adsorbed q,
phase
concentration,
q (moles/cc) slope=q

Co
Fluid phase concentration, c (moles/cc)

Lt qo= Dimensionless
Co 0 co Henry's constant, K


Figure 3. Favorable adsorption isotherm.


Winter 1998


TABLE 1
Details of the Experimental Apparatus Shown in Figure 1.

Item Manufacturer Model/Part No. Range/Size
Mass Flow Controllers
Helium line Brooks 5850E (Controller) 0-10 l/m
0151E (display)
Oxygen line J & W 200-2002 built-in span adjustment from 1 cc/m to 1000 cc/m

Jacketed Adsorption Column (stainless steel) Fabricated in the Pressure tested at 200 psi
Length: 40 cm workshop
Inner tube: 1 1/2 inch; schedule 40
Outer tube: 2 1/2 inch; schedule: 40

Temperature Regulated Water Circulation Poly Science 9101 10-950C; 7 or 15 1/m

Oxygen Analyzer SERVOMEX 572 Output: 0-1 V for 0-100% oxygen

Chart Recorder Rikadenki R-61A 100 mV full-scale setting was used

Pressure Gauge WIKA 0-100 psi

On-Off Valves Whitey SS-41S2 1/8 inch

Plumbing
Stainless steel tube 1/8 inch
Male connector Swagelok SS-200-1-2 1/8 inch
Union Swagelok SS-200-6 1/8 inch
Union elbow Swagelok SS-200-9 1/8 inch

Adsorbent Carbon molecular sieve: Shirasigi MSG 3A from coconut shell. Provided by a local
pharmaceutical company from the supply for their PSA nitrogen unit.











to the limiting heat of adsorption, AUo = AH + RgT. For cal-
culating AH, from AUo, the average temperature of the
experimental range is used.
On the other hand, if the Henry's constant is expressed in
terms of adsorbate pressure (we denote it by K'=K/R'T,
where R' is the gas constant in pressure units), then its
temperature dependence may be directly related to the heat
of adsorption
-AHo
K'= K' e R T

The desorption breakthrough is obtained when a saturated
bed is purged with inert. In the linear (and very low concen-
tration) range of the isotherm, the adsorption and desorption
profiles obtained at the same velocity are symmetric.
The system of equations that describe the dynamic re-
sponse of an adsorption column is given in Table 2. Analyti-
cal solution to the set of equations is given by Lapidus and
Amundson"1 in the form of complicated infinite integral. In
this study, numerical solution by the method of orthogonal
collocation is used. (The collocation form of the model
equations may be obtained from the author upon request.)
The input parameters for the model are
Column length, L -> given (40 cm)
Bed voidage, e -4 given (0.35)
Column radius, R -> given (2.05 cm)
Adsorbent particle radius, Rp -- given (0.1 cm)
Interstitial feed velocity, vo = uo / -> uo is calculated
from the flow rate measured during experiment
(cm/s)
Equilibrium constant, K obtained from the break-
through curve
Peclet number, Pe determined from available


correlation
Mass transfer parameter, k -- to be determined by
matching the experimental breakthrough curve

voL
Pe =
DL
where DL = 0.7 Dm + voRp
The molecular diffusivity of the adsorbate in the carrier is
Dm(cm2/s) and may be calculated from Chapman-Enskog's
equation.[2] All known commercial adsorbents offer external
film, macropore, and micropore resistances to the transport
of the adsorbate molecules from the bulk phase to the inte-
rior adsorption sites. A linear driving force (LDF) rate model
is used here to represent the transport across these resis-
tances, k is the overall LDF rate constant. The LDF model
approximates a distributed resistance to be confined in an
equivalent thin zone. The individual resistances linearly add
up to give the overall LDF resistance, 1/k:


1 RpK
k 3 kf
external
film
resistance


RK
+ p
15 De


r2
15 D
15 D,


macropore micropore
resistance resistance


The LDF model may be viewed as a lumped parameter
model with the luxury of relating the overall constant to the
more fundamental parameters that characterize the constitu-
tive transport processes. The film mass transfer coefficient,
kf, may be calculated from the following correlation pro-
posed by Wakao and Funazkri:131
Sh = 2.0 + 1.1 Re-6 Sc1/3
where
Sh Sherwood number = 2 kfRp/Dm
Re Reynold's number = (2 Rp)puo 1/
Sc Schmidt number = g / pD,


TABLE 2
Model Assumptions and Equations
(In the following equations, Y is the mole fraction of the adsorbable component in the gas phase;
z is the axial distance; t is the time; P is the total system pressure; and 4 is the total adsorbed amount. Other symbols are defined in the text.)

Item Assumptions Equation

a&y Dy ay I -E RgTO aq=
Fluid phase component material balance Isothermal -DL + v + + --E = 0
D z2 + z 3t E P at
The flow pattern is described by the axial
Continuity condition dispersed plug flow P # f(z) # f(t)

Flow boundary conditions The frictional pressure drop is negligible D Y = y 0
Flow boundary conditions D Lc p^- =-V'0 Y -Y =0
Ideal gas law holds az z=o z + Z =L
The mass transfer rates are represented by q ,_
Mass transfer between fluid and particle linear driving force rate expressions t = k q)

Equilibrium isotherm Linear isotherm = Kc = KcY

'8 Chemical Engineering Education











p, p density and viscosity, respectively.
The above correlation is particularly recommended as it was
able to reconcile experimental data from a large number of
sources.

EpD,
De =

where 1/Dp = 1/Dm + I/DK
The Knudson diffusivity, DK (cm2/s), becomes important
when collision of the diffusing species with the pore walls
becomes significant in comparison to the intermolecular col-
lision. Poiseuille flow and surface diffusion are two other
parallel contributions to transport in the macropores.
Poiseuille flow is neglected since the pressure range in which
it becomes important will not be encountered in this study.
Surface diffusion occurs through the adsorbed layer on
the macropore walls. This is commonly found to be impor-
tant in homogeneous adsorbents, such as activated carbon,
activated alumina, silica gel, etc. For composite adsorbents,
such as carbon molecular sieve and pelleted zeolites, the
adsorption capacity is mainly in the micropores; the
macropore walls are practically inert and the condition for
surface diffusion to occur does not arise. Therefore, surface
diffusion is also neglected, since we will study the adsorp-
tion and diffusion of oxygen in carbon molecular sieve. Of
course, in the chosen system, both molecular and Knudson
diffusion are much faster than the micropore diffusion and
may be neglected as well. Nevertheless, these terms are
discussed further in view of their wider conceptual impor-
tance as mechanisms of transport in porous media in general.
Knudsen diffusivity is given by


D = 9700 T(

where
4 pore radius (cm)
T temperature (in absolute units)
M molecular weight of the adsorbate
Ep, r absorbent particle voidage and tortuosity, respectively.

A typical value for / Ep is approximately 10.

Therefore, in the expression for mass transfer parameter,
the micropore diffusional time constant, Dc / r1, is the only
unknown that is determined by matching the model solution
for a breakthrough with the experimental response. Micropore
diffusion is an activated process and follows Arrhenius-type
temperature dependence
-E
D, = DcoeRgT

A semilogarithmic plot of D, vs. 1/T, known in the literature
as the Eyring plot, will give the activation energy, E, from
the slope and the pre-exponential factor, D0o, as the intercept.
For some adsorbents, such as carbon molecular sieve, r,

Winter 1998


cannot be measured explicitly. In such cases, D. / rf is plot-
ted against 1/T, which yields Dco / rf as an intercept.

EXPERIMENTAL PROCEDURE
The study of adsorption and diffusion of oxygen in a
carbon molecular sieve is chosen as the model system here.
Helium is used as the inert carrier. The following set of
instructions is provided to guide the students through the
various steps of the experiment.
The oxygen analyzer response should be checked for 0 and
100% oxygen. The output range is 0-1 V and is linear. The
calibration curve for the mass flow controller used for the
carrier gas is provided. The total mixed flow can be easily
determined by analyzing its oxygen content.
It is suggested that the interstitial feed velocity in the column
and oxygen concentration in the feed are maintained between
5 and 10 cm/s and between 2 and 4%, respectively. The
adsorption column should be bypassed during flow and
concentration adjustments. The system gauge pressure should
not exceed 0.5 bar. The effluent is analyzed using the oxygen
analyzer.
A chart recorder is used to record the analyzer signal. The
chart speed and range setting must ensure sufficient resolu-
tion of the output signal from the oxygen analyzer as a
function of time.
Water (from a temperature-regulated tank) is circulated
through the jacket of the column at the desired temperature.
The measurements should be conducted at three temperatures
in the range of 30 to 500C. The choice of temperatures should
be evenly spaced and at least 45 minutes must be allowed for
the bed to attain thermal equilibrium with the circulating
water. It is also recommended to move from low to high
temperature.
The bed should be purged with helium until the 0 V baseline
is attained. This ensures a clean bed with respect to oxygen.
Introduction of the oxygen step in the feed and switching the
chart on at the desired speed must occur simultaneously.
It is essential that the breakthrough curves be measured until
completion.
It is necessary to record the desorption breakthrough curve for
at least one temperature in order to check linearity of the
isotherm at the chosen concentration level.
Other than the formal desorption run, the bed is regenerated
by purging with helium and increase in temperature. The
adsorption breakthrough measurement is repeated when the
bed has been completely regenerated and has attained the new
temperature.

RESULTS AND DISCUSSION

The students are required to include the following results
in their report on the experiment:
1. Plot of c/co vs. time for adsorption and (1-c/co) vs. time
for desorption on the same graph in order to check the
symmetry.










2. Ko, AUo, and AHo values from the semilogarithmic
plot of K vs. 1/T.
3. Dco / r2 and E values from the semilogarithmic plot
of D /r,2 vs. 1/T.
Typical plots are shown in Figures 4 through 6. The param-
eter values determined from these plots are also shown in the
respective figures. The equilibrium constant is obtained di-
rectly from the mean residence time calculated by integrat-
ing the breakthrough curves, as discussed earlier. The mass
transfer parameter is obtained by matching the breakthrough
profiles with the model solution. The effect of the mass
transfer coefficient on the model solution is shown in Figure
7. It is clear that the model solution is quite sensitive to the
value of k. The students are reminded that several numerical
techniques are available to determine the best-fit values.
But students carry out all the necessary computations and
calculations in the laboratory and, in view of the limited
laboratory time, they are allowed to use eye estimation to
decide on the best fit.
While using the above method to measure D / r2, it is
extremely important to remember that all the dispersive ef-
fects in an adsorption column (namely, axial dispersion,
external film, and intraparticle diffusional resistances) that
are identified in the mathematical model have similar effects
on the shape of the breakthrough curve. Therefore, these
effects cannot be separated from a single experiment. More-
over, since the resistances are linearly additive, there is
always a risk of misinterpreting the results. Hence, there is
an inherent need to always ensure that the rate parameter
under investigation is indeed the controlling factor of the
process dynamics. Reliable accounting of other effects is
also necessary when they are not completely negligible.
Estimation of external film and macropore resistances are
more reliable than prediction of axial dispersion.
Maldistribution of gas flow and extra-column effects con-
tribute to additional axial dispersion unpredictable by pub-
lished correlations. Agglomeration of small particles may
also result in excessive axial dispersion (see reference 3 for a
comprehensive discussion). All these possibilities were taken
into account while designing the experimental system used
here. In order to ensure proper flow distribution, the column
size was chosen to satisfy the recommended column-to-
particle diameter ratio. Furthermore, 1/8-inch tubes and fit-
ting were used to minimize extra-column mixing effects. In
spite of all these precautions, experimental verification is
recommended to confirm that the associated dispersive ef-
fects are correctly estimated.
Although the available laboratory time is not sufficient to
include such supporting experiments, the students do not
remain ignorant on these matters. In addition to writing a
general discussion on the findings, they are also asked to
suggest an experiment to prove that the present system is
micropore-diffusion controlled and to comment on the effect
80


o 0.8 -
0.6 A
n 0.4 ] A Adsorption
S0.2 o 0 Desorption
S0.2-

0 50 100 150 200 250 300
Time (s)

Figure 4. Symmetry of the adsorption and desorption
breakthrough curves in the linear range of the equilibrium
isotherm.


100
AUo = -3.5 kcallmol; AH, = -4.1 kcal/mol

10


1 I -
0.003 0.0031 0.0032 0.0033 0.0034
1/T (K1)

Figure 5. Temperature dependence of Henry's constant
(oxygen in a carbon molecular sieve) showing that it
follows Arrhenius Law.


1.00E-01
E = 4.12 kcallmol
'
0, 1.00E-02 I___


1.00E-03
0.003 0.0031 0.0032 0.0033 0.0034
1/T (K1)

Figure 6. Eyring plot showing temperature dependence of
micropore diffusivity for the diffusion of oxygen in a
carbon molecular sieve.



1
0.8
S- k=0.10 (/s)
O. --k=0.20 (ls)
S0.4 k=0.05 (Is)
0.2. L Expt
0 1
0 50 100 150 200 250 300
Time (s)

Figure 7. Effect of LDF mass transfer coefficient (k) on the
model solution.
Chemical Engineering Education









of macropore size and operating pressure on the macropore
resistance. These questions guide their thoughts to the fol-
lowing important points:
*For a micropore-controlled system, a reduction in the
macroparticle size should not affect the mass transfer kinetics.
Hence, when the k value remains unaffected by a change in the
particle size, it serves as clear proof that the axial dispersion
and macropore resistance are practically negligible. On the
other hand, a variation in values estimated from experimental
runs with different particle size and/or at different velocities
will indicate that the secondary resistances are not negligible
and their contributions have not been properly estimated.
*The importance of Knudsen diffusivity depends on the effective
macropore size and is independent of pressure, whereas mo-
lecular diffusivity is inversely proportional to pressure and may
affect the overall transport rate at a higher pressure.

CONCLUSIONS
This laboratory exercise introduces the students to the
calculations of equilibrium and kinetic parameters for an
adsorption separation process. The use of a dynamic model
for the extraction of the mass transfer parameter provides a
useful visualization of the role of this parameter on process
performance. The simulation model can also be effectively
used to illustrate in detail the numerical solution of a system
of coupled partial differential equations. The consistency of
results obtained by different groups is encouraging. Equilib-
rium capacity and mass transfer resistance of the chosen
system are well suited for completing the required number
of runs and necessary computations in one standard labora-
tory session of six hours.

REFERENCES
1. Lapidus, L., and N.R. Amundson, J. ofPhy. Chem., 56, 984
(1952)
2. Sherwood, T.K., R.L. Pigford, and C.R. Wilke, Mass Trans-
fer, McGraw-Hill, New York, NY; Chap. 2
3. Ruthven, D.M., Principles of Adsorption and Adsorption
Processes, Wiley Interscience, New York, NY, Chap. 7 (1984)




BOOK REVIEW: Batch Distillation
Continued from page 13.

Example 1.2 are easily misinterpreted. And there is a tech-
nical mistake in the calculation of the heat to the reboiler in
Eqs. (2.13) and (2.17). The author ignores the energy re-
quired to vaporize the distillate product in the reboiler.
Equation 2.13 should be QR=X(R+I)D.
The graduate-level material starts in Chapter 3, "Column
Dynamics," which derives the unsteady mass and energy
balances. Then error, stability, and a summary of numerical
integration techniques are presented. The need for an inte-
gration technique capable of handling stiff equations is
clearly illustrated in Example 3.1. The chapter is completed
Winter 1998


with sections on start-up and approximate models. There
are some parts that will confuse students. For example, the
numbering of stages in Figure 3.1 does not agree with the
equations, and derivation of Eq. (3.44) requires assump-
tions not mentioned in the text.
The author is clearly an expert on the application of
shortcut (Fenske-Underwood-Gilliland) methods to batch
distillation. Readers are told to "be careful in choosing the
appropriate value for the light key and heavy key for suc-
cessful use of this method," but how to be careful is not
explained. This and other small mysteries will cause confu-
sion. The modified shortcut method developed next re-
quires lumping a number of plates into compartments.
Other than comparison with an exact solution, no guid-
ance is given on how to select the number of plates in
each compartment. The last section on the hierarchy of
models in the simulator will be very helpful to students
using the simulator.
Chapter 5, "Optimization," describes objective functions,
degree of freedom analysis, feasibility, and the general frame-
work of solution methods. This chapter is quite general and
would benefit greatly from numerical examples. Chapter 6
on optimal control problems builds on Chapter 5. This
chapter would also benefit from numerical examples in
addition to the derivation examples.
The last chapter analyzes azeotropic systems and col-
umns with a middle vessel. Since most students will be
unfamiliar with the analysis of steady state azeotropic dis-
tillation, more details on residue curve maps and synthesis
of batch distillation systems would be welcome. The short-
cut method is extended to binary azeotropic systems and
simple ternary systems. Extension to more complicated ter-
nary azeotropic systems would be welcome.
The index appears to be quite well done. An author index
would be appreciated. The reference lists at the end of each
chapter appear to include all the important historical and
recent papers. The nomenclature list is quite complete, and
the tables that summarize the equations after each theoreti-
cal development are helpful. The type is easy to read and
there appear to be few typographical errors. Unfortunately,
the figures are not of professional quality and are difficult to
interpret. Many of the figures have multiple curves that are
not labeled. When two theories are compared on the same
figure, the reader needs to guess which is which. The curves
are not smooth and it is often unclear if the wiggles are real
or due to the plotting routine.
Every chemical engineering department should obtain a
copy for their library's reserve section. Chapters 1 and 2
will be helpful as a reference for undergraduates doing
laboratory or design projects on binary batch distillation.
The remainder of the book will help graduate students and
professors who occasionally encounter multicomponent
batch distillation problems. O










classroom


COMBUSTION SYNTHESIS

AND MATERIALS PROCESSING

Student Exercises *


DANIEL E. ROSNER
Yale University New Haven, CT 06520-8286

The student exercises below are representative of those
developed for the Yale graduate course, "Combustion for
Synthesis and Materials Processing," described in the fall
issue of CEE (page 228). Among other purposes, they demon-
strate that rather simple but quite rational calculations can be
made to estimate approximately how large a combustion reac-
tor must be in order to produce, say, a metric ton of high-
value product every hour. Such preliminary design calcula-
tions are prudent first steps before considering more detailed
follow-on calculations. They also develop a young engineer's
intuition and provide interesting CS/MP examples of the im-
portant role of the ChE core subjects: chemical thermody-
namics, homogeneous/heterogeneous chemical kinetics, trans-
port phenomena, separation processes, and chemical reaction
engineering. All notation is that of the author (Ref 7, loc cit.).
Educators interested in further CS/MP exercises can contact
the author at Yale University or electronically via
rosner@ htcre.eng.yale.edu

EXERCISE 1
Consider the combustor volume required for sulfur spray
combustion at 1.4 atm at the S(1) feed rate of 50 t/d.
a) If efficient S(1) spray combustors can be operated at
volumetric chemical energy release rates, < em >, of
about 2 MW/m3, then what volume should be provided
for a 50 t/d unit?
b) How does this average volumetric chemical energy re-
lease rate compare to that in a small oil burner for home
heating? Or a gas turbine engine combustor (at 3 GW/m3
at 30 atm) when corrected down to 1.4 atm? (cf. Fig. 1,
loc cit.)
c) If the amount of excess air used is that required for the
combustion product mixture to have a temperature near
1400 K, then what will be the mean residence time (ms)
in such a sulfur burner?
d) Estimate the time required to heat up a 100 jtm S(1)
droplet from 415 K to 700 K if the liquid heat capacity is
Copyright ChE Division ofASEE 1997


estimated as 0.28 cal/g-K and the density is 1.8 g/cm3.
e) Estimate the time required to burn a 100 jum S(1) droplet
at approximately 700 K if the latent heat of S(1) vapor-
ization is 0.42 kcal/g and the ambient conditions are
(002,o = 0.232, T, = 350K.
f) What phenomena would lengthen the time required to
completely convert all S(1) droplets beyond your esti-
mates from parts "d" and "e" above?
g) Is the combustor volume provided in part (a) likely to be
adequate in this case? What would be the next steps you
would recommend before "cutting metal"?


EXERCISE 2
a) Does the successful growth of diamond films from gas
mixtures containing CH3(g) and H(g) at 1 atm on 1200 K
surfaces shake your confidence in the value of thermo-
dynamic principles to judge the feasibility of chemical
syntheses, generally? (See reference 1, below.) Does
combustion synthesis of diamond films under these con-
ditions violate the second law of thermodynamics? Dis-
cuss the broader implications of this recent discovery.
b) Approximately 20 pm (volume equivalent) diameter dia-
mond crystallites (grains) are grown from rich C2,H/02
flames impinging on 1200 K solid targets at p=l atm.
How many carats are these? (1 carat = 200 mg). How do
they compare to the 30-mg diamonds synthesized (since
1954) by GE Corporation at p = 30 kbar, T = 2200 K? To
get a physical feel for this pressure, convert to the units:
metric tons (force) / (mm)2.
c) Consider the phase equilibrium C(graphite) <>C(diamond)
in the single element system: carbon, from the viewpoint
of the Gibbs phase rule. How many state variables are
needed to define this system?
d) We know that CH2(g) can be commercially synthesized
from the pyrolysis of methane, CH4(g), via a partial
combustion process at acceptable yields. It is interesting
that diamond film growth is found to be possible via the
Chemical Engineering Education









fuel-rich combustion of either C,H2(g) or CH4(g), but the
maximum attainable growth rates (often expressed in
microns/h) have been found to be larger for acetylene by
factors of nearly 20. Considering the overall economics,
how would you decide on which carbonaceous fuel to
use if your goal is to grow commerically interesting
diamond films?


EXERCISE 3
Consider the preliminary design (sizing) of a 25 t/d acety-
lene synthesis reactor (near-plug-flow, axi-symmetric) to
operate at near-atmospheric pressure. Based on preliminary
laboratory data, it appears that the partial oxidation of pre-
heated methane using oxygen, followed by approximately 1
ms. cracking at about 1800 K (before a water-spray quench
to 350 K) leads to a product stream with about 8 mole pet.
acetylene vapor and, unavoidably, produces solid carbon
soot at the rate of about 50 kg/t C2H,. Preheating both
(unmixed) reagents to about 900 K is considered the highest
safe temperature choice to avoid autoignition upstream of
the burner block/flame-holder. Make a self-consistent pre-
liminary choice of all essential dimensions in the course of
answering the following specific questions.
a) If the overall stoichiometry of the partial combustion of
methane is CH4(g) + (1/2)0,(g) --CO(g) + 2 H,(g), then
estimate the individual Oz(g) and CH4(g) mass flow rates
(kg/s).
b) Before turning to the turbulent jet mixing-diffuser sec-
tion, estimate the required dimensions of a stable burner/
flame-holder, including the channel diameters, number
of channels, and open area fraction. Also select the down-
stream "cracking chamber" dimensions. For these pur-
poses use the following tentative estimates: flame speed,
S, (rich CH4/0O) = 28 cm/s at 298 K, 1 atm; d In S,/d fn
T, = 1.86 for methane/air; (L/U),cking section = 1 ms. What
factors should govern the channel (hole) lengths? (cf.
Fig. 4, loc cit.)
c) Is the heat of partial combustion [CH4(g) + (1/2) O,(g)
-CO(g) + 2 H2(g)] sufficient to raise the preheated
mixture of methane and oxygen from 900 K to the crack-
ing temperature of 1800 K without the addition of auxil-
iary oxygen at the burner/flame-holder location? Tenta-
tively, neglect the possibly appreciable heat losses to a
(water-cooled?) burner/flame holder.
d) Estimate the heating value of the solid carbon removed
from this unit if it could be recovered and burned to
CO2(g).
e) What factors dictate the quench water-flow-rate require-
ment? What spray velocities and drop sizes should be
used? (cf. Fig. 4, loc cit.)
f) How would your choices of dimensions change if you
Winter 1998


opted for a synthesis reactor operating at 5 atm? For this
purpose, note that the effective order of the methane
oxidation corresponding to previously observed Su(p)-
data for combustion with air is about 1.4.
g) Returning to the turbulent jet mixing-diffuser section, can
you provide a rough estimate (bound?) of the required
length, the transverse dimensions (diameters) for the 1
atm device? For all of the above items, spell out and
defend all further assumptions you introduce.


EXERCISE 4
The surface of one C60 molecule contains 20 hexagons and
12 pentagons. Based on the presumption that the C-C bond
distance in Co is close to that in the graphite crystal (1.42 A)
estimate
a) The surface area of one C,6 molecule.
b) The effective diameter of one Co6 molecule.
c) Use the result in part b to estimate the Fick molecular
diffusion coefficient of C,6 with respect to CO,(g) at
2100 K and 100 Torr (via hard-sphere kinetic theory).
d) Compare the specific surface area (m2/g) of C,, to that of
commercial activated carbon as well as flame soot (con-
taining non-porous primary particles of 30 nm diameter).
What conclusions) do you draw from this?
e) Extrapolating from the information provided in the re-
cent review of Howard (1992), suppose that C60 could be
produced in a 100 Torr benzene/O, combustor at a yield
of 0.5 pet. of the fuel carbon. If the burner C/O ratio is
about 0.9, use the present costs of benzene ($/kg) and 02
($/std. m3) to
1) Estimate the fuel cost per kg. of C6o produced and 02
cost per kg of C,, produced.
2) Estimate the pumping cost per kg of C60 produced.
3) Compare the sum of these costs to the actual present
cost per kg. of C,0.
4) Is a combustion process currently used (by Aldrich,
Hoechst AG ...) to produce research quantities of
C60? What intrinsic advantages would a combustion
synthesis process have over rival (electric spark and
laser pulse/graphite feed) methods?
f) Use the reported equilibrium vapor pressure of crystal-
line Co,(s) to estimate the frost point temperature of C,6
in the abovementioned synthesis flame. Is a partial de-
sublimation separation method feasible for harvesting
C60 in this case?

REFERENCES
1. Dodge, B.F., "Application of Thermodynamics to Chemical
Reaction Equilibria," Trans. Amer. Inst. Chem. Eng., 34,
529(1938) 0











elff curriculum




JUST A


COMMUNICATIONS


COURSE?

Or Training for

Life after the University


GUIDO BENDRICH
University of New Brunswick
Fredericton, New Brunswick, Canada E3B 5A3

oday, many chemical engineering curricula include

courses in strength of materials, electronics, heat and
mass transfer, reactor engineering, plant design, eco-
nomics, communication skills, etc. Competence and techni-
cal expertise alone, however, will not guarantee graduates
(or, as a matter of fact, anyone) a job in today's economy.
We should not only teach our students the necessary tools to
enable them to survive in a work environment but we should
also assist them in their transition from the university to
industry. While there are career placement services on al-
most every university, their success in helping students find
suitable employment after graduation is usually limited.
Having noted these difficulties in the past, I felt a need to
become more actively involved in assisting students to find
employment. Our students are now being given an early
opportunity, as part of a two-credit-hour course in "Commu-
nications and Information Systems,"'" to learn more about
technical report writing, oral presentation skills, computer
applications, and life after the university.
Many publications have been written on the subject of
developing good communication skills.[2'31 This paper dis-
cusses the techniques used to teach students the principles of
critical thinking, communication skills, and up-to-date com-

Guido Bendrich joined the Department of
Chemical Engineering at the University of New
Brunswick after spending some nineteen years
in various industrial settings throughout the
world. He obtained a PhD from McMaster Uni-
versity in 1992. His teaching and research inter-
ests are in industrial plant design, cost estima-
tion, plastics processing, developing communi-
cation skills, and education.


Copyright ChE Division ofASEE 1998


TABLE 1
Course Objectives (Short Version)

You will bring your own interests and we shall discuss how they may
be incorporated into the ChE 1014 course. We have an academic
responsibility also to ensure that we aim for certain learning objectives
and, for this course, those objectives are as follows:
1. Development of communication skills through oral and written
presentations.
2. Familiarization with current information technologies.
Learning Objectives
Learning at this stage of your education means the development of
critical skills. In this course, therefore, you will be
0 articulating facts, concepts, principles, and rules;
'problem solving in real life situations;
'using effective communication skills;
interacting productively in small and large group settings; and
Ioenjoying yourself too!

The Tools
We shall select practical examples to illustrate the principles of critical
thinking, communication skills, and up-to-date computer technologies.
The main part of the course shall be centered around the area of "Job
Hunting." The following steps will not only describe the course
structure in more detail but also present a possible application of the
material studied to a real-life situation.
> Career Assessment the most critical phase in the whole process
We shall discuss the various aspects in the area of Critical
Thinking Skills and how we can make good use of it at home, in
school or in a work environment.
Decision Making all about choices
In order to make educated decisions one must have access to
pertinent information. We shall explore different ways of
obtaining the necessary information, e.g. libraries, databases and
the Internet.
The Resumi--a very effective marketing tool
The development of a great r6sum6 requires of computer
technology. We shall familiarize ourselves with the use of various
computer applications such as word processors, databases, etc.
> The Job Market
You will present in a 10-minute oral presentation some detailed
information on the industry of your interest. We shall explore the
use of overhead transparencies and computer-based presentation
techniques. In addition, you will be given an opportunity to
summarize your findings in the form of a technical report.
I The Cover Letter
The writing of cover letters, i.e., letters of transmittal, is an
important part in an engineer's working life. We shall learn about
the various styles of cover letters.
> The Interview
We shall reinforce our critical thinking skills, learn about active
listening, observe and diagnose verbal and nonverbal messages,
and, most importantly, learn how to handle problem (stress)
situations. Practice interviews will assist in refining these skills.
I The Tale of a Success Story
At this stage, the course is coming to an end. You have not only
learned about various computer applications, literature searches,
oral and written presentations, and critical thinking skills but, more
importantly, you have had an opportunity to apply of these
techniques to different situations in your daily life.


Chemical Engineering Education











TABLE 2
Six Thinking Hats (Reference: Edward deBono'61)

Color of Hat Characteristics Questions
White Facts, figures, objective material, ... What information do I need to make a decision?
How can this information be obtained?
Red Feelings, emotions, intuition,.. How do I feel about it?
What does my "inner voice" say about this?
Black Logical negative arguments,.. What are the risks?
What does "Murphy's Law" say about this?
Yellow Possibilities, opportunities, ... What are the advantages?
What is the best-case scenario?
Green Creative new ideas, .. Can I come up with a more innovative approach?
Blue Master control for the thinking process Summarize results
Review of results

Name: Date: / /



TABLE 3
Suggested Career-Related Topics to Think About

Topic Results from the Six Thinking Hats
Intellectual challenge
Meaningful work
Opportunity to learn new things
Sense of achievement
Creativity
Interpersonal relationships
Salary
Benefits
Job Security
Social Status
Promotions
Opportunity to travel
Personal growth
Independence
Fast-paced
Future power
Variety of tasks
Exciting, stimulating

1. Study the ten most important value items; do you notice any specific patterns?
2. Develop an "I can do" list by identifying some actions that will integrate your expectations in
educational strategy.

Name Date


Winter 1998


puter technologies based on real-world
applications such as "finding the right
job." The course objectives are out-
lined in Table 1. The following steps
highlight the techniques used to
achieve these goals:

> Critical Thinking Skills

S. R. Covey'14 discusses the four
unique human endowments of imagi-
nation, conscience, independent will,
and self-awareness. Imagination, as
defined by Covey, is "the ability to
envision, to see the potential, to create
with our minds what we cannot see at
the present with our eyes." This abil-
ity does not come naturally, but it can
be learned. The Critical Thinking
Skills segment of this course provides
the students with insight in the deci-
sion-making process. Some of the
techniques discussed in detail are ones
described by Covey,[4] deBono,[61 and
Butler and Hope.?1] These techniques
aid students in discovering more about
themselves.
In one exercise, based on deBono's
approach, each class participant is
asked to imagine six colored hats. Each
hat represents a role one's mind plays
in the critical thinking process. By
switching from one hat to another as
one thinks about a topic, the learner is
forced to look at the topic from a vari-
ety of perspectives.'5' For the exercise,
the students start with six sheets of
paper-one for each hat. They select a
topic or problem that they would like to
think about or work on. Each partici-
pant decides which of the hats would
be good to start with and then works
his/her way through all six, writing
down notes on the thoughts that come
to them with each hat. Table 2 identi-
fies the six hats, their characteristics
and some of the questions one should
ask with each one.1"' The students may
think of other questions as well.
If the learner has worked a problem
through all six hats and has written
down at least three points for each, he/
she will know that all the major points
in the critical thinking process were
covered. Table 3 presents some sug-
85











gested career-related headings that may be used to
explore the critical thinking process.
This and similar exercises will not only help the
students learn more about themselves but they can
also aid the students in identifying their long-term
career objectives. A significant increase in self-
awareness can be observed over the course of the
term.

- Computer Applications

In this part of the course various computer applica-
tions, such as word processors, spreadsheets, data-
bases, e-mail and Internet tools, are introduced to the
students. Guidance is provided through the use of
slides, handouts, and extensive hands-on exercises.

Obtaining Information

Information Technology is the buzzword of the 90s,
and in that vein, an in-depth summary called "The
Retrieval of Information" is presented to the students.
Among the topics discussed in class are library and
CD ROM searches, organization of database systems,
and "how to surf" the Internet.
Assignments in this section focus on topics such as
"Retrieve information about injection molding of poly-
meric materials," or "Retrieve the latest information
in the area of pulp bleaching." The search results are
then reported, as discussed below, both orally and in
the form of a written report. The added benefit of
these exercises is that the students are, at the same
time, also broadening their knowledge in the general
area of chemical engineering.

- Technical Writing

In this section of the course, topics such as techni-
cal writing and document layout are introduced to the
students. The assignment topics (technical reports)
are based on information retrieved in the Obtaining
Information section, and in addition, the students are
introduced to different types of r6sum6s.
One approach that has proven to be successful (but
by no means the only appropriate model) can be found
in "The Job Hunting Guide."171 Excerpts of this docu-
ment are shown in Table 4. Guidance is provided in
the r6sum6 development process through slides, hand-
outs, and hands-on exercises. The most important part
of this document is the Objective section. Here the
writer addresses the very important issues of "What
skill do I bring to this position?" and "What can I do
for the Company?" The insight obtained in the sec-
tion on Critical Thinking Skills will guide the partici-
pants in the development of this subsection.


TABLE 4
The Resume
A Very Effective Marketing Tool

The next step, after having successfully completed the career-planning phase, is
the development of a r6sume. If developed properly, it can be a highly effective
marketing tool. Its two main purposes are to advertise your availability and to supply
information to the recruiter.
How should a resume be prepared? Perhaps the most important thing to remem-
ber is that the format must capture the recruiter. It should enable the recruiter to
quickly find the key points. Clear headings, off-white paper, and point format are
desirable. Remember that you will have less than ten minutes to prove to the person
that you are an exceptional candidate. Effective use of language, emphasis on
achievements, and quantified experience are thus important aspects of a resume.
There are three basic formats being used today. The most widely used and
accepted format, the chronological style, lists your experiences in reverse chrono-
logical order. This style emphasizes your most recent achievements. The functional
format lists the duties performed by category. With this style, it is harder for the
recruiter to get an instant picture of the candidate. The third type, which is not widely
used, is a hybrid of the chronological and the functional format styles.
What key information should a resume contain? The following eleven categories
should be included:
Personal Data The only data required are your name, address, and phone number.
Your fax number and e-mail address are optional. One would not want to supply
information such as religion, marital status, or citizenship. These are 'knock-out'
factors that may or may not be used against you. You do not want to limit your
chances right from the beginning.
Career Objective There is some debate on whether or not this section should be
included in a r6sum6. Unless the objective is written carefully, do not include it. This
section should show what you can do for the company and NOT what the company
can do for you. A sample objective for a person who has participated in a Co-Op
Professional Experience Program could read: "To provide leadership in industrial
research and development activities, where strength in superior analysis of data,
problem solving, innovation, and excellent communication skills will: design and
develop new technologies, provide opportunity for technology transfer, train and
motivate staff and generate results consistent with organizational initiatives.
Professional Profile This summarizes your professional experience in a few short
sentences. The following could be used as a guideline: "Engineering experience
relating to injection molding, process automation, and the modeling of PET resin
drying processes.
Education List your education in reverse chronological order. Do not include your
high school education if you have a college or university degree.
Work Experience Describe all the relevant work experiences here. Use action
verbs such as directed, developed, implemented, designed, and presented to describe
your accomplishments. Do not forget to include your job titles, times of employ-
ment, and the names of your employers.
Selected Achievements This section should list a maximum of three work/educa-
tion-related accomplishments in more detail.
Professional Development This category should include all professional develop-
ment activities that you have undertaken outside of the standard engineering curricu-
lum.
Scholarships List all your scholarships.
Professional Affiliations Are you a member of a profession organization? List it
here.
Languages Indicate the languages you know and your level of competence. If you
are fluent in English and can "get by" in Spanish, you should write "Fluent in
English andfunctional in Spanish."
References "Available upon request." Do not include the names of your (three)
references in your resume. Prepare the list of references on a separate sheet to be
used as a handout during the interview.


Chemical Engineering Education











TABLE 5
Oral Presentation Evaluation Form

Comments/Mark
Opening Statements
Did the speak state her/his name?
Did the presenter state the topic?
Did the presenter state the purpose?
Did the presenter outline the presentation?
Organization
Is there a logical flow or a rambling monologue?
Does the presentation target the audience?
Is the presentation informing or merely trying to impress?
Presentation
Is presenter enthusiastic about the topic?
Is the speaking clear or mumbled?
Is the presentation delivered in a professional manner?
Was eye contact made?
Is the talk too long (past target time)?
Were the gestures distracting?
Is the speaker still or walking nervously?
Is the dress code appropriate?
Is the presentation natural and not read?
Visual Aids
Is the layout of the visuals appropriate?
Do they contain a reasonable amount of information?
Are they referred to rather than read from?
Is the grammar correct?
Are they shown for less than one minute?
Subject Knowledge
Does the presenter master the subject?
Closing Remarks
Is the objective statement repeated?
Is the presentation summarized?
Are proper acknowledgments made?
Were the questions answered concisely?


TABLE 6
Discussion and Listening Skills

Interviewer:
Interviewee:
Question:
Or question number from list _
Needs
Evaluation of Interviewer Improvement Good Short C
Eye contact
Body language
Oral communication
Self-confidence: "Think on your feet."

Needs
Evaluation of Interviewee Improvement Good Short C
Eye contact
Body language
Oral communication
Self-confidence: "Think on your feet."_

More detailed comments from the observer should be submitted on a separate

Name Date

Winter 1998


A significant amount of effort by the students is volun-
tarily directed toward the development of this document.
This high degree of motivation may be attributed to the
fact that they are doing something for their own benefit,
i.e. they can apply these skills during their studies as well
as in their life after university.

Presentation Skills

An emphasis on the development of presentation skills
in universities has significantly increased over the past
decade.12 In our course, each student is given the oppor-
tunity to make a formal presentation to the entire class
twice during the term. In a short, three-minute presenta-
tion, topics such as "The use of NaCI in the pulp and paper
industry" or "Recent developments in the area of power
generation" are presented to the whole class. Also, a ten-
minute presentation summarizes the results obtained in
the "Obtaining Information" section. A detailed discus-
sion on the presenter's performance is scheduled on a one-
to-one basis. The Oral Presentation Evaluation Form (Table
5) serves as an aid in this process.
In addition to these "formal" presentations, the students
participate actively in short exercises throughout the term.
At the beginning of each lecture, one student, selected at
random by the instructor, must summarize the previous
class in about three minutes. This exercise serves two
purposes: everybody comes to class prepared and it
gives the students yet another opportunity to hone their
presentation skills. In addition to the above described
exercises, students enjoy frequently-held "one-minute"
impromptu talks.

Discussion and Listening Skills

The way a person asks and answers ques-
tions impacts significantly on the working en-
vironment. Questioning is a valuable tool and
is critical to the oral communication process.
Many successful approaches have been de-
scribed in the literature.' 901 The students learn
about and practice how to ask, as well as how
comments to answer, two basic types of questions: open-
ended and closed-ended.
As the communication process suggests, for
communication to be congruent, one has to
clearly understand the other's frame of refer-
omments ence. The students gain this understanding by
asking questions that will clarify and confirm
the messages others are sending to them. After
the students were encouraged to engage in dis-
cussions, they observe and diagnose the other's
sheet, verbal and nonverbal messages. Through group
exercises and continuous feedback (see Table
6), one observes significant improvements in










the students' performance.

0 Real Life Situations
Employers emphasize that interpersonal and
communications skills are as important as tech-
nical knowledge. Through group exercises, the
students are given several opportunities to prac-
tice different interviewing situations. Learning
how to ask questions, and learning how to
answer difficult ones, does not come quickly.
Practice makes perfect. The skills and knowl-
edge obtained in this course help the students
to overcome interview anxiety.

DISCUSSION
The purpose of this course is to help students
hone their communication skills. In addition,
the students will learn more about themselves
and their goals. These techniques, tested and


We should
not only teach
our students
the necessary'
tools
to enable them
to survive in a
work environment
but we should
also assist them
in their
transition from
the university
to industry.


refined over many years, work well in both university and
non-university environments. When the concept was first
being introduced, there were comments from our students
such as:

> "This instructor is crazy. He is trying to teach us
communication skills and at the same time he is
asking us to learn more about ourselves!"

> "1 am just a second year student. I can't use this
concept to go after technical summer jobs!"

After a few students tried the approach, the following com-
ments were made:

> "I got a job using the communication skills and job
hunting techniques that I learned in your class."

> "Thank you for your efforts. My communication skills
improved significantly."

Initially, the students have to learn how to overcome their
fears. Active support by the instructor is the key in this
process. Support begins with the instructor's in-depth under-
standing of the course material and its adaptation to the
specific learning environment.
This course, unlike ordinary lecture courses, requires a
significant amount of student/instructor interaction outside
the scheduled class time. During the course of the term, the
instructor should have several private review meetings with
each student. The focus of these meeting should be on work-
ing together to achieve the goals that were set out in the
course outline. By answering questions, resolving problems,
and emphasizing good communication skills, these meetings
can help foster an understanding and a strong commitment
of the learner to her/his chosen profession. The instructor's
responses during the meetings should be positive and sup-


I portive. This will help ensure that the established


goals are successful and are harmonious with those
of the rest of the class.
By the end of the course, the students have not
only significantly enhanced their communication
skills, which of course is our main objective, but
they should have also gained an enhanced self-
awareness that will help them along their chosen
career path.

CONCLUSIONS
A course such as "Communications and Infor-
mation Systems" can be taught through the appli-
cation of real life situations. Although there are
currently many discussions being held about the
university's role in today's society, the author
strongly believes that, if one strikes the proper
balance between the economically driven goals
(i.e., the education of marketable students) and the


more traditional goals of the university (i.e., let's educate
great thinkers), this approach will serve the students well in
the future. "Let us not lose sight of the results we seek to
achieve as we focus of the process of providing relevant
chemical engineering education for the 21st century."[10]

ACKNOWLEDGEMENTS
The author would like to thank Brian Lowry for his valu-
able input on the "job hunting" topic while co-teaching the
ChE 1014 course. Special thanks are due to Frank Collins,
Robin Chaplin, Don Woods and all the course/seminar par-
ticipants for their assistance in refining the concepts.

REFERENCES
1. Bendrich, G., and B.J. Lowry, "Communications and Infor-
mation Systems Course Material," University of New
Brunswick (1996)
2. Nirdosh, I., "Making Successful Oral Presentations-A
Guide," Chem. Eng. Ed., 31(1), 52, (1997)
3. Lordeon, S.L., C.H. Miles, and M. Keane, Some Assembly
Required-A Complete Guide to Technical Communications,
McGraw-Hill Ryerson Limited, Toronto, Canada (1997)
4. Covey, S.R., The 7 Habits of Highly Effective People, Simon
& Schuster, New York, NY (1989)
5. Butler, G., and T. Hope, Managing Your Mind, Oxford Uni-
versity Press, New York, NY (1996)
6. DeBono, E., Six Thinking Hats, Penguin, New York, NY
(1985)
7. Bendrich, G., "The Job Hunting Guide," Personal Notes
(1994) and http://www.unb.ca/che (1997)
8. Newell, J.A., D.K. Ludlow, and S.P.K. Sternberg, "Develop-
ment of Oral and Written Communication Skills," Chem.
Eng. Ed., 31(2), 116, (1997)
9. Kauffman, K.J., "How to Make Questioning Work for You,"
Chem. Eng. Ed., 31(2), 134, (1997)
10. McKeachie, W.J., Teaching Tips, D.C. Heath and Company,
Lexington, KY (1994)
11. Buonopane, R.A., "Engineering Education for the 21st Cen-
tury," Chem. Eng. Ed., 31(2), 166, (1997) 0


Chemical Engineering Education

















AUTHOR GUIDELINES


This guide is offered to aid authors in preparing manuscripts for Chemical Engineering Education (CEE), a quarterly
journal published by the Chemical Engineering Division of the American Society for Engineering Education (ASEE).
CEE publishes papers in the broad field of chemical engineering education. Papers generally describe a course, a
laboratory, a ChE department, a ChE educator, a ChE curriculum, research program, machine computation, special
instructional programs, or give views and opinions on various topics of interest to the profession.


Specific suggestions on preparing papers *
TITLE Use specific and informative titles. They should be as brief as possible, consistent with the need for defining
the subject area covered by the paper.

AUTHORSHIP Be consistent in authorship designation. Use first name, second initial, and surname. Give complete
mailing address of place where work was conducted. If current address is different, include it in a footnote on title page.

ABSTRACT: KEY WORDS Include an abstract of less than seventy-five words and a list (5 or less) of keywords

TEXT We request that manuscripts not exceed twelve double-spaced typewritten pages in length. Longer
manuscripts may be returned to the authors) for revision/shortening before being reviewed. Assume your reader is not
a novice in the field. Include only as much history as is needed to provide background for the particular material covered
in your paper. Sectionalize the article and insert brief appropriate headings.

TABLES Avoid tables and graphs which involve duplication or superfluous data. If you can use a graph, do not
include a table. If the reader needs the table, omit the graph. Substitute a few typical results for lengthy tables when
practical. Avoid computer printouts.

NOMENCLATURE Follow nomenclature style of Chemical Abstracts; avoid trivial names. If trade names are
used, define at point of first use. Trade names should carry an initial capital only, with no accompanying footnote. Use
consistent units of measurement and give dimensions for all terms. Write all equations and formulas clearly, and number
important equations consecutively.

ACKNOWLEDGMENT Include in acknowledgment only such credits as are essential.

LITERATURE CITED References should be numbered and listed on a separate sheet in the order occurring in the
text.

COPY REQUIREMENTS Send two legible copies of the typed (double-spaced) manuscript on standard letter-size
paper. Submit original drawings (or clear prints) of graphs and diagrams on separate sheets of paper, and include clear
glossy prints of any photographs that will be used. Choose graph papers with blue cross-sectional lines; other colors
interfere with good reproduction. Label ordinates and abscissas of graphs along the axes and outside the graph proper.
Figure captions and legends will be set in type and need not be lettered on the drawings. Number all illustrations
consecutively. Supply all captions and legends typed on a separate page. State in cover letter if drawings or photographs
are to be returned. Authors should also include brief biographical sketches and recent photographs with the manuscript.


Send your manuscript to
Chemical Engineering Education, c/o Chemical Engineering Department
University of Florida, Gainesville, FL 32611-6005







Full Text
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PAGE 1

N .. ~ ... i::s l,l :: "i::s ~ ... == ~ ... ,,; ,:, ~ l,l C 1:1) == i::s l,l ~ ... "' ... S: == ~ N .. C ~ "' ~ ;. i::s ~ l,l ~ 0,0 S: == ~ -== ... w "o' N .. ~ ... :: ... ~ ... "' i::s N l,l .::: ~ S: N .. i::s -== l,l w ~ ... S: chemical engineering education Chemical Engineering and the Other Humanities (pg 14) J.M. Prau.1 n i t: COMET : An Open-Ended Hands-On Project for ChE Sophomores (pg. 20) .. .... ...... ........ ..... .... ....... ... Mark R. Prau.1n't:: Animal Guts as Ideal Reactors ( pg. 24 I ......... Carlson. Gust Toward Technical Understanding: Part 3 Advanced Levels (pg. 30) .. .. ...... ... Ha,'le Helpful Hints for Effective Teaching ( pg. 36) .. ...... .. Dm i.1 Experiments Illustrating Phase Partitioning and Tran s port of Environmental Contaminants (pg. 401 .. .. Pmras Grimherg Random Thoughts: Ships Passing in the \"ight (pg. 46J Industry: Make Summer Internship a Leaming Experience (pg -18) .... An Introductory ChE Course for First-Year Students !pg 52) Freshman Design Projects in the Environmental Health and Safety Department (pg. 58) lnnnvativc Ways of Teaching Polymerization Reactor Engineering I pg 62) .. . Practical Hints for Gathering Information (pg 68) Advice from an Old-Timer I pg. 72) .. .. An Undergraduate Experiment on Adsorption (pg 76) .. Combustion Synthesis and Materials Processing: Student Exercises I pg. 82) .. Just a Commumcations Course > Or Training for Life after the l niversity lpg. 8-ll .... . .............................. Fl'iaer .. ...... lfu\'(/rd Solen. Harb Wille, Pnce Soares, Penlidis, Hwnielec ......... Ranllde .. ..... Mllclean .. Farooq ................................. Rt1s11er .. Bendnrh

PAGE 2

Visit us on our new web page at http://che.ufl.edu/ cee/

PAGE 3

EDITORIAL AND BUSINESS ADDRESS: Chemical Engineering Education Department of Chemical Engineering University of Florida Gainesvill e, FL 32611 PHO NE a11d FAX: 3 5 2 -39 2 -0 86 1 e -mail: cee@c h e .ufl. e du W eb Page : http ://c h e. ufl .e du /cee/ EDITOR T. J. Anderson ASSOCIATE EDITOR Phillip C. Wankat MANAGING EDITOR Carole Yocum PROBLEM EDITORS James 0. Wilkes and Mark A. Burns Un i versity of Michigan LEARNING IN INDUSTRY EDITOR William J. Koro s University of Texas, Austin PUBLI C ATION S BO AR D CHAIRMAN E. Dend y Sloan, Jr Colorado School of Min es PAST CHAIRMEN Gary Poehlein Georgia In stitute of T ec hn ology Klau s Timmerhaus University of Colorado MEMBERS Diann e Dorland University of Minn esota, Duluth Thomas F. Edgar University of T exas at Austin Richard M. Felder North Carolina State University Bruce A. Finlayson University of Washington H Scott Fogler University of Michigan David F. Ollis North Ca r olina State University A ngelo J Pema New J e r sey In stitute of T echnology Ronald W. Rous se au Georgia I nstitute of Technology Stanley I. Sandler Univers i ty of Delawar e Ri c hard C. Seagrave I owa State University M. Sami Selim Colorado School of Mines Jam es E. Stice University of Texa s at Austin Donald R. Woods McMast e r University Wint e r 1998 Chemical Engineering Education V o l ume 32 Number 1 Winter 1998 EDUCATOR 2 Arvi nd Varma, of Notre Dame Anne K o la czyk DEPARTMENT 8 Way n e State University CURRICULUM 14 Chemical Engineering and the Other Humanities J.M. Prau sni t z 52 An Introductory ChE Course for First-Year Student s, Kenn et h A. Solen, J ohn N. H arb 58 Fre s hman De sign Projects in the Environmental Health a nd Safety Department, Ronald J Willey, John M. Pri ce 62 Innovative Ways of Teach in g Polymerization Reactor Enginee rin g: Exc h a n g in g In formation Between the Universi t y an d Industry Joii o B.P Soares, Alexander Penlidis Archie E Hami elec 84 Ju st a Communications Course ? Or Trainin g for Life after the University, Guido Bendrich CLASSROOM 20 COMET: An Open-Ended, H ands-On Project for ChE Sophomo r es, Mark R. Prausnit z 24 Animal Guts as Ideal Reactor s: An Open-Ended Project for a Course in Kinetic s and R eactor De s ign Eric D. Carlson, Alice P. Gast 36 Helpful Hint s for Effective Teaching R obert H. Da vis 68 Practical Hint s for Gathering In forma tion Saidas M. R anade 82 Combustion Synthesis and Materials Proce ss ing : Student Exerc i ses, Dani el E. R osner LOOKING BACK 72 Adv i ce from an Old-Timer W. Dan Maclean LEARNING 30 Toward Technical U nd erstanding: Part 3. Adva n ced Levels J.M. H aile LABORATORY 40 Exper im ents Illustrating Phase Partitioning and Transport of Environme nt a l Co ntamin a nt s Susan E. Po wers, Stefan J. Grimberg 76 An Unde r graduate Experiment on Adsorption, Shamsuzz.aman Farooq RANDOM THOUGHTS 46 Ships P assing in the Night, Ri c hard M Feld er LEARNING IN INDUSTRY 48 Make Summer Intern s hip a Learnin g Expe ri ence, Gary S. H uvard 13 Letter to the Editor 13 29 Book Review s C H EM I CAL ENG I NEE RI NG EDUCA TIO N ( IS SN 0009-2479 ) is published quart e rly b y th e Chemical Engineering Division America n Society for E 11 gi n eeri n g Ed u c at ion and is ed it e d at the U ni ve r s ity of Florida. Correspo11dence regarding edi t oria l matt er, circu l atio n a nd c han ges of add r ess shou ld be se nt t o CEE, C h e mi ca l E ngineerin g D e partm e nt, U niv e r s i ty of Florida, Gainesville FL 32611 6005 Copyright 1998 by the C hemi ca l Engineering Division American Society for E n gi n ee rin g Ed ucati o n The sta t e m e nt s and opi ni o n s ex pre sse d in th is p erio dical ar e tho se of th e writers and n ot n ecessa ril y th ose of th e C h E Division ASEE, which body assu m es n o r es pon si bi l ity for th e m Def ec ti ve copies replaced if 11otifi ed within 1 2 0 da ys of publication Write for information on s ubscription cos ts a,rd for ba c k copy co sts and availability PO STMASTE R : Sen d address c han ges to CEE, C h e mical Engineering Department., U niv ers ity o f Florida Gainesville, F L 326 11 -60 0 5. Periodicals P os tag e Paid at G ain esv ill e, Florida. 1

PAGE 4

[!j9$i educator ) a..1-1111111---______ .;.._.... Arvind Varma of Notre Dame ANNE KOLACZ\'K Universit y of Notre Dam e Notre Dame IN 46556 W hen Arvind Varma was awarded the Univer s ity of Notre Dame 's Colle ge of Engineerin g Out s tandin g Teacher of the Year Award for 1990-91, hi s s tudent s prai se d him as "a n excellent teacher both in a nd out of th e classroom ," a nd sa id he showed a "g reat interest in hi s s tudent s" and was "w illin g to be a friend and a m e ntor. The y cited hi s ex t e n s i ve avai labilit y, say in g it was "a rare and valuable o pportunit y to work with a person with s uch g reat character and work e thi c. He will b e the pro fessor whom we will vividly remember twenty years from now and hi s influence will be m a tched b y few in our lifetime ." Th e awar d and the citation that acco mpanied it were gratifying to Arvind, who believe s that the most important thing a teacher can be is a good model for the s tudent s. Whether you are in the cla ss room or doing research, you must always do things the right way ," h e says. "A t eac her should not ju s t impart inform a tion but s hould also teach s tudent s how to think, how to li ve. You need to teach c ritical analysis so that the y are a bl e t o ask que s tion s, to make d ec i sio n s on their own. You can rely on people and other so urces for inform a tion but you s hould be able to analyze on yo ur own to make deci s ion s Th a t ability to analyze i s what he hope s he ha s taught hi s s tud e nt s. Carmo J Pereira a former s tudent who is now a Princip a l Con s ultant at DuPont Engineering, believ es he learned that ability as Varma 's s tudent. When I first met Profe sso r Varma, he had ju s t arrived at Notre Dame after two years in indu s try. I am a practicing reaction e ngine e r today in large part due to him His love for reaction engineer ing hi s great attention to d e t ai l an d hi s dedication to th e profe ss ion Ann K olaczyk is Publ ications Editor in the College of Engine e ring at th e University o f Notre D ame. This articl e was w r itten with assistance from the faculty of the D epa rtm ent of Ch e mical Engineering. Copyright ChE Diuision of ASEE 199 8 2 and Asa y oung faculty member in the late 1970s, and Asa graduate student in the late 1960s, Asan undergraduate student in the mid-1960s. Chemica l Engin ee ring Education

PAGE 5

[Arvind] sa y s, A teacher should not just impart informat i on but should also teach students how to think how to li v e. You need to teach critical anal y sis so that the y are able to ask questions to make decisions on their own. are truly contagious! I have been greatly influenced by Pro fessor Varma's desire to excel, and I have attempted to follow his example Another former st u dent Bala Subramaniam (now a chaired professor of chemical and petroleum engineering at the Uni versity of Kansas in Lawrence) says, "Professor Varma's research accomplishments are well known and recognized. What is probably not as well known is that Professor Varma is also a gifted teacher with exemplary dedication and excel lence in educating his students." He adds, "His lectures are intellectually stimulating, characterized by careful prepara tion and energetic delivery. Professor Varma brought to his class the latest research developments from his program as well as others This allows students to gain a better apprecia tion of creativity, which in turn inspires them to be creative He is very accessible to his students, and whenever interact ing with them either in or outside class, he creates an atmo sphere that promotes the students' desire to learn and to excel. Personally, these experiences have helped shape my teaching philosophy and methods to a great extent." Arvind was born in Ferozabad U.P. India the fourth of seven children. He had always been a good student and, due to double promotions, was only 15 years old when he gradu ated from high school in 1962. This made choosing a college difficult because most of the schools in lnclia had age restric tions and required incoming freshmen to be at least 17 or 18 years old. The Indian Institutes of Technology were just starting then and were already prestigious but they too had age restrictions. Arvind had done well in chemistry and mathematics in high school and was looking at chemical engineering on the advice of his father, who was a civil engineer working in government service. When Arvind learned that Panjab Uni versity in Chandigarh (one of the schools without an age restriction) had recently started a chemical engineering pro gram with American collaboration, he applied there and was accepted. It was a unique situation in that the engineering college affiliated with the school had the other engineering disciplines on its own campus but the new chemical engi neering department was autonomous and was housed on the main university campus. The chairman of the department was Professor B G h osh. He was you n g, o u tstandi n g, and bright. Recent l y re tu rned Winter 1998 from Carnegie Tech (now Carnegie-Mellon), he was a thoughtful teacher, and through him, Arvind was exposed to a more American style of teaching. Professor Ghosh's classes were more open and discussion-based, and he didn t insist on such a strict student/teacher division. It was at this time that teaching as a profession began to appeal to Arvind. "The idea of standing up in front of class, explaining things, talking about what you knew was very appealing to me," Arvind says. "I decided during my freshman year to be a college teacher." When he finished his undergraduate work Arvind was still only 19 years old and was anxious to come to North America for his graduate work. His parents weren't too keen on his leaving the country, but he was ready for new chal lenges. He applied to a few places in Canada and eventually chose the University of New Brunswick where he would have the chance to work with Frank Steward in combustion of solid fuels. At the University of New Brunswick he was exposed to even more of the Western s tyle of teaching further convinc ing him that he wanted to be an educator. But in his second year of graduate school, Frank Steward took a UNESCO appointment, and Arvind decided to change schools to pur sue his doctorate The University of Minnesota was rated very highly then as it is now, and he was accepted and awarded an assistantship there. During the late 1960s and 1970s the University of Minne sota was an exciting place to be. A great deal of research was being done in the area of analysis of chemical engineering systems, particularly mathematical analysis. This effort was led by Professor Neal Amundson who was department head and also Arvind s thesis advisor. Amundson had gathered together a top-notch faculty, many of whom had degrees in the sciences or math rather than in chemical engi n eering. At this same time, the Mining and Meta ll urgical Engineering Department was closing down and materials scie n ce was brought into chemical engineering This mixture produced an emphasis on the fundamental scientific aspects of chemi cal engineering-the engineering science approach-in which there is an application of surface chemistry, bio l ogy mat h ematics, and physics to chemical e n gineering problems This mixture of discip li nes i s more common now, especially in research gro up s, bu t it was very un u sua l at t h at time. 3

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At the University of Minnesota, Arvind was influenced greatly by both Profes s or Neal Amundson and Professor Rutherford Aris Besides being an innovative leader, Amundson was a brilliant teacher and researcher. He taught a two-hour course on math ematical methods in chemical engineering twice a week and did all hi s complex computa tion s on the chalkboard without any notes. Aris was a great scholar and writer, very fluent with words and widely pub lished. He was a soft-spoken, kind gentleman. Where Amundson was Arvind 's model of an innovator and teacher, Aris was his model of a scholar. During this period Karen and Arvind also became proud parents of their first child, Anita, born in 1974. Karen had worked as a laboratory assistant in microbiology s ince her graduation two years earlier, but now gave up her career to become a full-time mother. In 1971 Arvind married his wife Karen, then a senior ma joring in biology at the Univer sity of Minnesota. A few days after getting married they spent six weeks in India, meeting his Arvind with two people who shaped his academic development-Neal Amundson and Rutherford Aris-at Aris' retirement festivities in 1996 In 1975, after two years at Union Carbide Arvind received an offer from the University of Notre Dame. The chemical en gineering department there was well known due to the work in catalytic reaction engineering done by James Carberry and Ernest Thiele (who was no longer at Notre Dame but who had added greatly to the stature of the department ) as well as the work in thermodynamics and phase equilibria being done by James Kohn and Kraemer Luks. Also the department's chair man Julius Banchero was a well-known educator who was family and seeing the country. Arvind received his PhD in 1972 His thesis on Analysis of Tubular Reactor Multiple Steady States and Their Stability" generated a number of article s. After he was awarded his doctorate Arvind stayed on at the University of Minnesota as a temporary assis tant professor for one year, doing limited teaching while working on research During this period he got to know Pro fessors Amundson and Aris even better, as well as a number of other faculty members Arvind firmly believed that to be a good teacher one needed industrial experience (as Amundson and Aris had) so when he was ready to leave the University of Minnesota he interviewed both in academia and in industry. After con sidering offers from a number of sources, he went to work as a senior research engineer for Linde Research of Union Carbide in Tarrytown, New York where he did research in gas separations. The research at Union Carbide was very different from that which Arvind had done for this thesis, but that was part of its appeal since it meant his experience would become even broader. He was hired as a part of the Process Research Group, a newly formed unit that was looking into novel methods of gas separation processes Some of the projects that he worked on in their initial conceptual stages were a new process for breathing oxygen on aircraft, a new type of cryogenic insulation using thin evacuated glass microspheres, a zeolite slurry-based continuous gas separation process, and a parametric pumping system for an air separation process for producing oxygen for medical purposes. A number of these projects subsequently became commercial successes. 4 supportive of young faculty. Arvind decided to make the change to academia and was further convinced that the deci sion was a good one when Roger Schmitz came from the University of Illinois in 1979 to take over as department chair upon Banchero' s retirement. Arvind quickly progressed through the ranks, becoming a full professor in 1980, the same year that his younger daughter Sophia was born In 1982, Arvind became department chair himself when Roger Schmitz went on to become engineering dean. Al though Arvind was young for the po si tion he had definite ideas he was eager to implement and, under his leader ship, the department grew. During his tenure, Mark Mccready (the current department chair), David Leighton, and Hsueh-Chia Chang (who served as chair after Arvind) all joined the faculty. When he was chair, Arvind chose to teach the "Introduc tion to Chemical Engineering course himself because he thought it was important for the chair to be visible to the new students in the department. He also brought team teaching to the undergraduate labs with part of the faculty teaching the fall semester lab for seniors and another part teaching the spring lab for juniors. This had the dual effect of making it more interesting for the faculty to teach and encouraging camaraderie as they worked together. It was also good for students to have contact with a number of faculty members. The senior de sig n course is also team taught so every mem ber of the faculty instructs in one of these three courses every year. All three courses have written and oral reports due at the end of the semester. By implementing his ideas, Arvind helped to create an atmosphere of high standards for Chemical Engineering Education

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teaching and research. Mark Mccready chair of the department notes another aspect of Arvind's leadership While Arvind is well known for his mentoring of graduate students and hi s efforts to enhance these activities campus wide he ha s also mentored a number of current faculty at Notre Dame He provided a great deal of guidance to me during m y first few years here He helped with proposal and paper writing, encouraged my participation in departmental committees, and made sure that my views were heard. His efforts greatly enhanced my development as a junior faculty member. In order to devote full time to teaching and research Arvind decided to leave the department chair position in 1988 Within a few months of this decision, he was named the first occupant of the Arthur J. Schmitt endowed chair professorship, a position he still holds. All of Arvind 's research involves undergraduate, gradu ate, and post-doctoral students, true to his vision of an edu cator. When he was awarded the 1997 Burns Graduate School Award from the University of Notre Dame this pa s t May, the citation noted, in part that he is "a quintessential professor who excels in all phases of academic life and for whom there is no boundary between teaching and re searc h ." In his twenty-three years at Notre Dame twenty-seven students have completed their doctoral di sserta tion s under his direction, and severa l more are currently in progress. Every dissertation has resulted in coauthored publications in leading journals and typically in one or more paper presenta tion s at technical meetings. One of his students, Jean-Pascal Lebrat received the 1993 Graduate School Award in Engi neering in recognition of the quality of hi s dissertation re search. Furthermore largely through Arvind's efforts in coun seling and mentoring his former students have been very successful professionally in both industry and academia. Of his former PhD and post-doctoral students, eighteen are in academic positions at in s titutions around the world. "As a mentor Profe ss or Varma led and taught by ex ample. His enthusiasm for his research program was infec tiou s and evident during the weekly research group meet ing s," Bala Subramaniam says. Arvind 's early research involved various topics in chemi cal and catalytic reaction engineering, including diffu sio reaction in catalyst pellets reactor modeling and optimiza tion gas-liquid reactor s, and three-wa y catalysis for auto motive exhausts. Beginning in the early 1980 s, hi s focus was mainly in two areas. One area was the optimal distribution of catalyst in pellets in which the problem addressed is How should a fixed amount of catalyst be distributed in a pellet to optimize some specified performance index ?" This problem is common to all reactions that u se s upported catalysts. In systematic and innovative theoretical and experimental work, Arvind and his students have shown that the optimal distriWinter 1998 bution is a Dirac-delta function, i.e., the catalyst should be depo s ited at a specific radial position within the pellet. He ha s a lso developed experimental methods for preparing such catalysts This work has direct implication s for rational cata ly st de sig n and manufacture. The other area of Arvind's research during thi s period was parametric se n s itivity and runaway in chemical reactors. In certain regions of operating conditions, chemical reactors exhibit parametric se n si tivity whereby s mall changes in in put parameters lead to large changes in output variables. This behavior is common to all exothermic reaction sys tems. Determining these regions is of substantial interest because such behavior leads to deleterious reactor perfor mance. By original and penetrating analysis, confirmed by experiments, Arvind and hi s research group have provided rigorous and easily applicable criteria for identifying the regions of parametric se nsitivity and runaway for a variety of reacting sys tem s. For the last six to eight years, Arvind's research ha s been in the area of materials specifically the combustion synthe sis of materials. This is a large research program for mecha ni s tic studies of combustion synthesis: What is the mecha nism by which advanced materials such as ceramics, inter m e tallic s, and composites are synthesized by the novel tech nique called combustion synt he sis? How does the reaction occur? How is the product material formed? How can the microstructure of the material be controlled as it i s being synthesized? Because the microstructure affects the proper ties of the material by understanding the mechanism of the reaction and how the microstructure is formed, Arvind hopes to gain an understanding of the control over what the proper ties of the material are going to be Hi s funding for this research is from NSF and NASA. In the NASA program, Arvind i s looking at effects of gravity on combustion sy nthesi s of materials. Both the NSF and NASA programs have produced some unique results and new research techniques. One such technique, produc ing promising re s ults i s the high-speed microvideo record ing of the combustion wave front. "We are able to expand the wave front through magnifica tion u si ng a long focus microscope attached to a high-speed video camera," Arvind says. "We ca n increa se the s patial re so lution up to 800 times and can record up to 10 ,0 00 frames per seco nd. Arvind and hi s s tudent s can watch just how the rea c tion is occurring and can see many of the details of combustion wave propagation leading to a better understanding of how the wave front propagate s in heterogeneous reaction mix tures that are used for synthesizing advanced materials. They have the only facility in the world for doing this and are at the forefront of developing new techniques for under s tand ing how s uch reactions occur Using thi s novel technique, Arvind and hi s re search group ha ve identified new mode s of 5

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propagation that have never been witnessed before -t hey call it a scintillating reaction wave. In recent work, they have s hown that in many instances, the reaction initiates ahead of the wave front and sparks appear. They are the first precur sor of the main reaction that occurs a few milliseconds later. Another direction of Arvind's current research is inor ganic membranes With funding from the National Science Foundation and from indu s try (primarily Union Carbide ), he is studying various types of inorganic membranes-both metal composite membranes in which a thin (a few micron s thick), dense, metal film is deposited on a porous support, as well as ceramic membranes with controlled pore size and catalytic activity distributions He and his students have developed some novel techniques, such as the use of osmosis in conjunction with electroless plating. Using this idea they have synthesized high-flux thin metal composite membranes for both high temperature reaction and separation processes. In his current research Arvind is applying the principle s of chemical engineering and novel experimental techniques. His approach of combining theory and experiments, and of determining the influence of processing variables on the resulting microstructure and the reaction mechanism and extent, is having a strong impact on the materials synthesis field. He is frequently the only, or one of only a few, chemi cal engineers invited to speak at conferences related to the reaction synthesis of advanced materials Examples include the TMS Annual Meeting in 1991 and all four International Symposia on Self-Propagating High Temperature Synthesi s held in the former USSR (1991), Honolulu (1993), China (1995), and Spain (1997). His plenary lecture on the "Com bustion Synthesis of Advanced Materials" at the 1992 Inter national Symposium of Chemical Reaction Engineering ha s received considerable acclaim and attention as a landmark s ummary of research in this area. His forthcoming mono graph will update this work and has been praised already as "the seminal review on combustion synthesis." Arvind has published extensively in collaboration with Massimo Morbidelli, now a chaired professor at ETH in Zurich, Switzerland. Massimo came to Notre Dame in 1979 on a fellowship from Italy. He stayed only six months but wrote four papers while he was here and made a lasting impression on Arvind, who felt that he had great potential and encouraged him to get his advanced degree. His influence made a difference to Morbidelli. I decided to come back for my PhD," Massimo recalls, "But since I was a researcher at Politecnico de Milano I could not do it on a full-time basis. It was Dr Varma who arranged (with the help of the department chairman at that time Dr. Roger Schmitz) a semi-non-resident PhD program for me at Notre Dame. Since then Massimo and Arvind have written some forty articles and two books together making their collaboration one of the longer standing ones in academia. Their textbook 6 Mathematical Methods in Chemical Engineering (Oxford University Press) was published earlier this year, and Para metric Sensitivity in Chemical Systems (Cambridge Univer si ty Press), written jointly with research associate Hua Wu, was completed this past August and will be published early next year as part of the Cambridge Series in Chemical Engi neering of which Arvind is the founding editor. "I have continued my collaboration with Dr. Varma for almost twenty years now ," Massimo says, "A nd I find it always more exciting, a lthough we have now evolved in different research areas. But even recently, when after long hours together, one in front of the other at the sa me table reviewing our math book when we finished it, I felt the s ame sense of accomplishment as when we finished our first paper in 1979 I really felt I did something to my best without saving energies. This was in fact the program that Dr. Varma stated many years ago when starting the book adventure.' He'd told me .. and at the end we will s it together, read each page of the book, and leave there each word only if we like it. And it has been done This is really a great teaching for how to proceed in science, and I have seen this teachin g penetrating all my students who later came to work for longer or shorter periods of time with Dr. Varma from Italy: Alberto Servida Roberto Baratti Giacomo Cao, Hua Wu, Marco Apostolo, and others. Professor Varma ha s made s ignificant contributions to reaction engineering," Carmo Pereira says. Hi s work on optimizing catalyst intraparticle profiles and on high tem perature synthesis i s seminal, and he has received many honors for hi s work, including AIChE's prestigious Wilhelm Award." Arvind has also found time to serve the University of Notre Dame as well as many professional organizations. In 1992 he was awarded a Special Presidential Award by the University for his indefatigable energy in research writing, and all activities that engage hi s sharp mind and for serving simultaneously on a large number of university college, and departmental committees." He was a member of the University's Executive Committee of the Academic Council for three years, served on the Academic and Faculty Affairs Committe of the Board of Tru s tee s for three years, and was chairman of the Task Force on Research Systems as well as other committees. He i s a founding director of the Catalysis and Reaction Engineering Division of AIChE, serv ing a three -yea r term; a current member of the AIChE Awards Committee, serving a five-year term ; and has organized and chaired numerous technical sessions at national and interna tional conferences. Professor Varma's well-balanced contributions in teach ing research, and service are truly remarkable and make him the consummate profes sio nal and excellent role model that he is," Bala Subramaniam says. The fact that seve ral of hi s students have gone on to assume successful careers in acaChemical Engineering Education

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Arvind and Karen, along with his research group and their terrier Frankie, at a recent get-together at their home. A family photograph in traditional Indian dress on the occasion of older daughter Anita's marriage to Ken (also a chemical engineer) in May of 1997. On the left is younger daughter Sophia, currently a high school senior. T demia and in major companies is a testament to his excellent training and positive influence on his students." Roger Schmitz, Keating-Crawford Profe ssor of Chemical Engineering at Notre Dame, has worked with Arvind for eighteen years and says, I find it difficult to identify Arvind's strongest points because he excels in virtually every respect in his professional and personal life Few individuals can match the combination of trait s-dedication to academic work, motivation to exce l adherence to high sta ndard s of quality selflessness in service to the university and the profe ss ion boundle ss energy and capacity for work that make him a valuable member of our faculty and of our profession Massimo Morbidelli finds it hard to pick just one out standing attribute from the many things that he ha s learned from Arvind. The one that I am not s ure I ha ve learn ed, but one that I certainly admire is his hone sty in scie nce. B y this I mean not only of a moral but a lso of an intellectual n a ture. In particular s tating and writing a concept only after h e ha s tried by all means to clarify and to penetrate it. I do not recall a single time when he said, Well it doesn t matter. .. .' He always wanted to go as deep as possible in all aspects of a problem and in all details which was not a lways easy for grad students Another aspect was hi s profound knowledge of the literature and hi s capability of always giving appropriWint e r 1998 ate credit to all other researchers. " Above everything else, Professor Varma is an outstand ing individual who treat s hi s s tudents with courtesy and fairness ," Subramaniam adds. Among the many memories that I cherish from my graduate s tudent s day s at Notre Dame are the cookouts and get-togethers at his house. Professor Varma and his wife Karen, are extremely gracious ho s ts and treated s tudent s to a variety of culinary dishe s, including, of course spicy Indian food! The friendships and associations forged there ha ve been long la s ting. At the AIChE annual meetings, Profe ssor Varma make s it a point to organize a dinner-outing with hi s former s tudent s. These outings have become a pleasant forum for developing new friendships as well as reminiscing about old times. Arvind 's commitment to hi s s tudent s extends beyond just the sc hooling years. He has truly lived his belief of being a model for them all. In s pite of the intense agenda of work and profe ss ional activities to which he hold s himself Arvind has managed to bal ance his time and interests between professional and fam ily obligations. He is quick to express pride in the accom pli s hments of Karen and his daughter s, and he considers his family to be the mo s t important element in his life. Anita is a 1996 Notre Dame graduate in political science. She worked for one year as a volunteer in the Americorps Vista project and is currently a fust-year law student in Washington, DC. Earlier this year, she married Ken Motolenich, a Notre Dame chemical engineering graduate with a ma s ter 's degree in environmental engineering from MIT. Their wedding in cluded both church and traditional Hindu ceremonies. Sophia is currently a se nior in high school, busy with college applications and has strong interests in drama and musical theatre Anticipating more free time in the future Karen ha s been preparing for the last several yea rs for a teacher 's certificate in high school science and ex pect s to start her teaching career next fall. She is also a n accomplished opera si nger. 0 7

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lejb=i departmen t ) ______ ...._ _____::_ _____ _____ Wayne State University T he Detroit metropolitan area is one of the largest in the United States Businesses of every size and kind, including the research and production facilities-and world head quarters-for the "Big Three" U.S. au tomobile companies and many of the high-tech companies that s upply them, are within a short drive of one another. The exci tement of these busines s and re searc h opportunities, combined with the natural attractions of the Great Lake State, bring nonstop traffic to the nearby airport as people from around the na tion and around the world stream into so utheastern Michigan I Amid this flurry of activity is Wayne State University and its Department of Chemical Engineering and Materials Science. The department chaired by Esin Gulari has 200 undergraduate s tu dent s, 120 graduate students, and 15 Wayne State's College of Engineering Building. full-time faculty members Students make full use of the research and employment possibilities presented by a large metropolitan setting and the facilities offered at a major urban research university-all while learning in s mall and intimate departmental classes more reminiscent of a privat e institution. THE UNIVERSITY AND THE METROPOLI T AN DE T ROIT AREA Wayne State University has the advantage of being in th e middle of it all, literally and figuratively. It s location in the heart of metropolitan Detroit gives both faculty member s and st udents the chance to explore great variety in the area's cultural and business communities. Metropolitan Detroit ha s a worldwide reputation as a dominant manufacturing hub, a nd it is also gaining recognition as a center for technologi cal innovation. Through various co-op programs and re searc h collaborations between hundreds of these companie s and Wayne State, students have the freedom to incorporate on-the-job training into their overall education. Most of Wayne State 's 31,000 st udents commute to WSU from the city and its suburbs, but thousands also come from other states and countries. The campus has a richly diver se faculty and student body bringing different and unique per s pectives to the classroom. In addition, the metropolitan Detroit area has all of the cultural attractions expected in an urban environment (most within easy walking di s tance of the WSU campus) along with the benefits of various recreational areas, man y sit uated on one of the s tate 's 11 ,000 lake s Sports are also prominent in Michigan. Detroit 's professional hockey football, base ball, and basketball teams draw so me of the nation 's mo st ent h usiastic audiences. Beyond its prime location Wayne State University ha s earned a reputation for its excellent educational, research, and community-service programs. For example, Wayne State i s ranked as a Carnegie I Re searc h University, placing it among the top 88 univer si ties nationwide to hold th e presti gious designation Conferred by the Carnegie Foundation Copyright ChE Divi sion of ASEE 1998 8 Chemical Engineering Education

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Chemical Engineering Faculty Members: Left to right, Professors Putatunda, Matthew, Kummler, Ng, Salley, Gulari, Kannan, Rothe, Mao, Shreve, Huang, McMicking, and Manke. for the Advancement of Teaching, this title is reserved for universities that meet highly selective criteria for emphasizing research in addition to undergraduate and graduate education. Wayne State University is in the middle of it all, and the Department of Chemical Engineering and Materials Science has taken its place as one of the university's premier departments. THE DEPARTMENT Students and faculty members alike find the Wayne State University Department of Chemical Engineering and Materials Science to be an ideal size-small enough to engender a sense of community yet large enough to provide varied curricular and research opportunities. The sense of community is most clearly evident among the faculty members, who often meet in groups to take casual lunches together or who spend time in one another's offices discussing progress in the lab or in the classroom. This atmosphere has also given rise to a number of stimulating research collaborations among faculty members. The department itself is a collaboration of sorts. In 1993 chemical engineering and materials science, two separate but complementary disciplines, extended the good reper toire they had already developed and merged. Opportunities arose for cross-listed courses and multidisciplinary laboratories For students, the dual-disciplined department also opens doors for them to have two or more faculty mentors In addition students can learn from classmates and faculty mem bers in the other discipline and begin to see their field through others' eyes. Departmental graduates find this kind of insight particularly useful in the workplace. The curriculum in the department is wide in scope The undergraduate program includes courses that promote an u n derstanding of physical, biological, and chemical operations and processes. Grad u ate students can choose from a breadth of electives toward the MS and PhD in c h emical engi n eering, the MS and P hD i n materials science and engineering, Winter 1998 The department ... has 200 undergraduate students 120 graduate students, and 15 full-time faculty members. Students make full use of the research and employment possibilities presented b y a large metropo l itan setting and the facilit i es offered at a major urban research univers i ty all while learning in small and intimate departmental classes more reminiscent of a private institution. 9

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and the MS in hazardous waste management. Specialized training is also available including graduate certificates in polymer engineering, environmental auditing, and haz ardous waste control. Outside of the classroom students make use of modern laboratory facilities throughout the Engineering Building computer workstations in the Engineering Building and around the campus, and a complete university research library The newly opened un dergraduate library provides ample st udy areas and ex tensive computer equipment for student use. THE UNDERGRADUATE PROGRA M sc hedule ha s day and evening courses to meet the need s of s tudents in the program Another unique educational venture in the department is the undergraduate seminar ser ies that brings in scie nti sts from industr y and academic in sti tution s along with now working alumni During eac h of the three semesters of se minars the undergraduate st udent s are required to attend, each s tu dent prepare s a memo for the department chair about his or her educational progress and thoughts about the overall de partmental program. The exer cise not only allows the stu dents to evaluate their goals, but it also helps the chair to prepare for the department 's future THE GRADUATE PROGRAM Going well against the grain WSU s Department of Chemical Engineering and Materials Science brings to gether the lower tuition rates of a public university the well-equipped laboratories of Professor Esin Gulari and Research Assistant Vikhar Khan peering at polymer phases The graduate program a t Wayne State 's Department of Chemical Engineering and Maa major research institution, and the small undergraduate class s ize s of a private college. This combination present s an excellent environment for its s tudents Class sizes are generally in the range of 20 to 25 s tudent s. In this more intimate setting, stu dents feel comfortable meet ing one-on-one with their professors and getting to know their classmates Students commonly create informal groups to work out complex study problem s or to prepare for tests both very effective learning tools. Research is also a meaningful aspect of the undergraduate educational experience within the department. Undergradu ate students can elect courses that involve research programs or can take part in one of the many active projects of the faculty member s by accepting st udent research assistant ships. Either way participating students can augment their course work (and their resumes) both by working clo se ly with professors who are conducting related research and by sharing a laboratory with highly trained graduate s tudent s and with other like-minded undergraduate students. While not a requirement at least half of the undergraduate students take part in the department's well-developed Coop erative Education Program The unique relationship between WSU and local industry helps to create the diverse opportu nities presented through the program. Participating students alternate full-time study terms with full-time work assign ments in nearby companies. The location of the university makes it easy for the students to commute from the work place to campus, and the department s accommodating course 10 terials Science is actually two programs : one designed for doctoral students pursuing full time thesis research and another for master's students pursu ing part-time course work. The opportunity for graduate thesis research is abundant. Student s, who come to Wayne State from the United States and all over the world choo s e a re searc h advisor from an internationally recognized faculty of active sc holar s. Re search topics available are particularly diverse and s pan many of the hot new areas of chemical engineering, in cluding supercritical processing interfacial phenomena ad vanced materials processing and bioengineering. Strong federal, industrial and internal support has re s ulted in the graduate facilities at Wayne State being seco nd to none. For example the department possesses several s tate of-the art instrument s, including atomic force microscopes, an integrated optical bio se n so r a rheo-optical FTIR spec trometer, various s hear and extensional flow rheometers, and an excimer-laser-based imaging sys tem. Additionally, connections with other research institutes on campus and with local industries provide access to unique chemical and material characterization facilities. Competitive stipends typi cally s upport the s tudents Another unique feature of the Wayne State graduate pro gram is the course-work master's degree program. Students who typically are working engineers from the local area, are able to complete their de grees in a reasonable time due to flexible course offerings and the university's convenient location. The department designs many of the courses in Chemical Engineering Education

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Salley Yurgelivic and Suzanne Dakin, Research Assistants. Professor Paul Van Tassel with Research Assistant Shaoxing Yang. Dr Joseph Smolinski and Research Assistant Zeynep Ergungor Winter 1998 The Under graduate Library on campus. collaboration with industry to ensure that the students are best trained to deal with the contemporary issues of the discipline. As evidence of the program 's s uccess Wayne State is currently the nation 's number-one conveyor of master 's degrees in chemical engineering. GRADUATE CERTIFICATE PROGRAMS Three graduate certificate program s round out the department 's curriculum: polymer engineering, environmen tal auditing, and hazardous waste control. The Graduate Certificate Program in Polymer Engineering provide s specialized education for working engineers and scientists. The program include s core courses and electives (s uch as composite material s, polymer rheology and poly mer kinetic s) that are developed with input from profes sio nal s in industry. Student s can complete the program in as little as one year. Designed with working professionals in mind the Hazard ous Waste Control and Environmental Auditing programs have a combination of core courses and more specialized electives. The Graduate Certificate Program in Hazardous Waste Control teache s state-of-the-art method s for he man agement, control, and dispo sa l of a broad range of hazardou s substances, wastes, and materials. Students also gain practi cal knowledge in meeting government guidelines for waste management. The Graduate Certificate Program in Environ mental Auditing covers the management assessment, and auditing of facilities and property, hazard identification exposure, analysis and risk characterization, regulatory noncompliance analysis, sources of liability and alterna tive s for corrective action RESEARCH Research conducted in the WSU Department of Chemical Engineering and Materials Science falls into three expansive areas; materials processing and synthesis; pollution preven tion and control; and bioengineering. Many of the department's facu lt y members have interests that combine more than one area (see Table 1 next page). The research ofEsin Gulari and Charles Manke recently gained public attention when they received the highly re garded Henry Ford Technology Award. They became the first non-Ford Motor Company employees to earn that distinction The award recognized their work in reducing misting of metal-working fluids in Ford 's manufacturing plants. The two professors worked closely with all three of the U.S. automotive companies, even using company research laboratories and manufacturing plants to refine and verify their result s. Both Howard Matthew and Guang-Zhao Mao hold Na tional Science Foundation Faculty Early Career Develop ment Program (CAREER) A wards. This pre s tigious award recognizes fac ulty members who embody the exciteme nt of 11

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12 TABLE 1 Faculty: WSU's Department of Chemical Engineering and Materials Science (Additional information through the CHE and MSE option on th e web pa ge at http: //www.e n g .wayne .e du ) Joh11 Be11ci ( PhD, University of Pennsylvania /9 89) Deformation a nd fracture of materials High-temperature mechanical properties of alloys, intermetallic compo und s, and ceramics Esi11 Gulari (PhD, California In stitute of Technology, 19 73) Thermodynamics and transport properties of pol yme r sol ution s and melts Processing of polymers with supercr iti cal fluids Light-scattering-based particle and drop-sizing te c hniqu es Yi11lim Hua11g (PhD Kansas State Universtiy 19 92) Pollution prevention a nd waste minimization Pr ocess design and sy nth esis Ra11garama1mja111 Ka1111a11 (PhD, California In st itut e of Technology, 1994) Dynamics of polym er i c syste m s and int erfaces Rh ea-optica l spec tro scopy and scattering techniques Ralph Kummler ( PhD J oh n s H opk ins University ( /966) Modeling of combined sewer overflows and se dim e nt s Chemical kinetics Computer sim ulation s Charles Ma11ke ( PhD Univers i ty of California-Berkeley, 19 83) Polymer processing and rheology Molecular dynamics a nd kinetic the o ry of polymeric liquid s Guang-Zhao Mao ( PhD U11iversity ofMin11esora, 1 994) Opto-electronic properties of thin films and crystals Self-assembly of polymers and surfac tant s Colloidal stabil ity of waterborne paints R ea l-tim e imaging of s urfa ce phenomena at the molecular level Howard Matthew (PhD, Wa y n e State University, 1992) Tissue engineering and biomaterial s Artificial organ substit ut es James McMicki11g (PhD Ohio State University 1961) Correlation of therm ody n amic data Si111011 Ng (P hD University of Michigan, 19 85) H e terogeneous catalysis Polymer kinetics Spectroscopic and thermal ana ly s i s of mat e rial s urface s Susil Putatu11da (PhD, Indi an In stitute of Technology, Bombay, 19 83) Effects of microstructure on fatigue Fracture toughness Creep in metals and alloys Erhard Rothe (PhD University of Michigan, / 959) Applications of hi g h powered UV la se r s Machining of electronic chips Diagnostics of internal combust i on Steve11 Salley ( PhD, D etroit University 1976) Biochemical/medical e n gi neerin g D esig n of artificial organs Immobili ze d enzyme reactors Gi11a Shreve ( PhD University of Michigan 1991) Environmental and bio c hemical applications Microbially mediated biotransforrnations Paul Va11 Tassel (PhD, University of Minnesota, 1993) Shape-selective catalysis Protein adso rption and bio se paration s research and learning. Matthew's research involves tissue engineering and biomaterials and is working toward developing tissueand organ-replacement systems. In one of his projects, he is investigating the use of polymer composites to fabricate small-diameter vascular grafts. The results are promising. Mao is working on surface templates made of molecule s of mixed functional groups, She uses the se molecular templates to induce and control the growth of dye crystals with tunable colors. Among other things, Susil Putatunda is a cast iron expert. His research centers on several areas including the development of high-carbon/high-silicon austempered steel, the fatigue and fracture behavior of austempered ductile cast iron and the development of a fatigue-damage model for polymer-ba se d composites. Another of the department 's many active research groups, led by Yinlun Huang, is studying intelligent process sys tems engineering and is developing a process synthesis methodology based on artificial intelligence and fuzzy logic. This work may lead to cost-effective, highly con trollable and environmentally benign process systems. In addition, the research group hopes to meld optimal pro duction with pollution prevention in electroplating plants. With its staff of full-time faculty member s, the depart ment encompasses a diversity of research intere s ts While the faculty members take cues from local industry, they are very often much more than industry problem so lvers; they are research innovators They develop the new tech nologies that entice industry to come to them THE FACULTY Faculty members new to WSU 's Department of Chemi cal Engineering and Materials Science are welcomed with substantial start-up funding and institutional s upport. They also find a firm advocate in the departmental chair. Once on board, faculty members continue to receive substantial internal support, including summer and grad uat e student support. The department 's faculty team comprises fifteen full time members each of whom holds a national reputation in his or her specialty, and four adjunct profes so rs who are affiliated with the graduate program The faculty members have received many awards from prestigious engineering organizations and other institutions in the profession The faculty of the Wayne State Department of Chemical Engineering and Materials Science has many research options and educational possibilities open to them and their students. Being part of a major research university located in the heart of a metropolitan area, they are able to explore them all. 0 Chemical Engineering Education

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t.A_..blllliiii..._1e_tt_e_r_t_o:.._t_h_e_e __ d..:..it::..:o :....:r ____ ) Dear Editor: In their recent article titled An Experiment to Characterize a Consolidating Packed Bed (CEE, 31(3), p 192 1997 ), Gerrard Hackborn, a nd Glass misinterpret the Kozeny equation fo r low g a s flow through packed beds and consequently arrive at an incorrect re s ult. The Kozen y equation as w ritt e n b y th ese a uth ors i s 8p = 5a 2 (! E) 2 hv / E 3 ( 1 ) (Nomenc l ature and numbering of equations follow tho se of the article crit i cized, with the addition that number s assigned to cor rected equations have the letter "a" appended to them. ) In thi s form of the equation, the term a s ignifies th e s pe c ific s ur face of th e particles in the packed bed i. e., particle s urfa ce area/particle vol ume and i s independent of the bed consolidation (ass umin g rigid particles ). Therefore in the a uthor s' t e rminol ogy, a = a 0 (3a) The specific s urface of the pack e d bed parti cle s u rface area/bed volume, i s given by the product a(I-E). Unfortunately, the authors incorrectly assume that a alone s ignifie s the s pe c ific s urface of the bed and hence they write a = a 0 h 0 / h (3) which is incorrect for a as u se d in Eq. (1). If in s tead of Eq (3), one correc tl y su b s titute s Eq. (3a) a nd the authors' Eq (2), into Eq. ( 1 ), the result is 5a 2 h 2 ( 1-E ) 2 v h 2 8p = 0 0 0 { h ( l E 0 )h O }3 or 8p = k v h 2 /(h G) 3 where and G=(l-E 0 ) h 0 Rearranging Eq. (Sa) gives (2) (4a) (Sa) (6a) (7) (h 2 v / 8pf 3 = k 113 hk 113 G (Sa) Thu s it is ( h 2 v / 8p )1' 3 and not ( v / 8p )1' 3, that s hould be plotted against h in order to lin ea rize Eq. (Sa). That approx imat e linearlization was actually obtained b y plotting ( v / 8p ) 113 in stea d of (h 2 v / 8p ) 113 against h can be attributed to the fact th at the maximum decrease in h 213 for the experiments performed was on l y 1-(0.41 / 0 .6 1) 213 = 23 %. The authors should note that if they were to s ub s titute their Eq. (9), (9) into Eq (1 ), the right-hand s ide of the latter equation wo uld then contain (1E) 4 in the numer a tor which i s clearly inc orrect. The error ari ses from the mi s interpretation of a, w hich is not the pack e d Wint er 199 8 bed s p ec ifi c s urface given b y Eq (9), but the particle s pecific s urfa ce g i ve n b y a= nD ~ !(n!6)D~ = 6/DP (9a) (A lternatel y, if we define a as the authors h ave done then the ( !E)2 term in Eq. (1) would di sa ppear .) D ear Pr ofessor Epstein: Professor Norman Epstein D epar tm e nt of Chemical Engineering Th e U ni ve r s i ty of Briti s h Columbia Thank yo u fo r pointing out th e correction, which make s the fit even better. Professor Mark Gerrard Gib=' book review ) a.alllllllll.._.., ____ Batch Distillation Simulation, Optimal Design and Control by Urmila M. Diw e kar Publi s hed b y T ay l o r & Francis, JJ0l Vermont Ave ., N. W. Suite 200, Washington DC 20005; 2 11 pages including index; $59 .95 ( 1995) Reviewed by Phillip C. Wankat Purdue Un i versi t y B atch processes a nd b a tch di st illation in particular are und erstu died in uni ve r s itie s The t y pic al undergraduat e se pa rations textbook devote s a s hort chapter to batch distilla tion and typical coverage in cour ses (CEE R 28 p 15 1994 ) i s from one to three cla ss period s. The average grad ate s tudent doe s no additional study of batch di s tillation. Yet, batch distillation i s a n increasingly important se para tion method in indu s tr y, and there i s s ignificant interest in batch di s tillation re searc h. B atch Di sti llati on, w hich is prim ar ily de sig ned to se rve as a te x tbook for a graduate course," is very timely. The companion sof tware MultiBatchDS (e ducation edition from CACHE Corp .) was not availab le and is not reviewed here. A review of the book a nd the software from a consultant's viewpoint was recently published (Chem. Engr. Progr., p 77 Jun e 1997 ). If the sof tware is available, this would be a good text for a gra duat el eve l course. There are 38 homework problems in the book which is probabl y s ufficient for the first time the course i s offered. With the exception that packed columns are not covered, the coverage is broad and most topics of interest are included Chapters 1 and 2 introduce batch distillation and a nalyze binary systems The se two chapters are a good resource for professor s and und ergraduate stude nt s, but some professo rial guidance will be needed For example. Eq. (1.6) and Continued on page 81. 13

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.t.a.5_.._ c_u_rr_1_c_u_l_u_m ________ .:....;) CHEMICAL ENGINEERING AND THE OTHER HUMANITIES J.M. PRAUSNITZ University of California Berkeley, CA 94720 H ow is engineering related to other intellectual or professional disciplines? What is the role of chemi cal engineering in a modem university, and how does it fit into the spectrum of knowledge? And, finally, what can possible answers to these questions tell us concern ing our educational philosophy and curriculum for training the engineers of the future ? These are difficult multidimen sio nal question s with many aspects. I will discuss here only one aspect, one that is essential but ha s not received much attention: the need to remember that chemical engineering is not an isolated sub ject; that it is not limited to applied science, but rather is a s ignificant part of daily life related to health, to human relationships to politics and soc iology and law, to the way we think and feel about ourselves as individuals and as members of society, to our aspirations, our hopes and our fears. In other words, I want to emphasize the old but too often forgotten concept that chemical engineering is not apart from, but indeed a part of, what (broadly speaking) we call the humanities. Toward introducing that concept, Figure 1 shows a faJ ohn M. Prau s nitz, Professor of Chemical Engi neering at the University of California, Berkeley has devoted most of his professional career to phase equilibria as required for process design. His undergraduate education was at Cornell Uni versity and he received his PhD from Princeton which also gave him an honorary Doctor of Sci ence degree two years ago. Author or coauthor of more than 500 technical publications he is the senior author of the widely used text Molecular Thermodynamics of Fluid-Phase Equilibria "' Adapted and abbreviated from a l ectu r e delivered at Notre Dam e University The University of Missouri-Columbia, and the University of Michigan (1996-97). mou s painting by Titian. The painting about 400 years old, is in the Borghese Palace in Rome and is titled Sacred and Profan e Lov e. Early in this century, a copy of the painting was on the wall of the seminar room of the Institute for Mathematics at the University of Gottingen in Germany. From the middle of the nineteenth century until 1933 when the Nazis started to destroy the German universities Gottingen was the world's leading center of mathematics attracting the best minds of the day. In the seminar room, underneath the painting was not the original title but a new one, Pur e and Applied Mathematics. We do not know who retitled Titian 's painting, but it was not only for amusement. The institute at Gottingen was far ahead of its time; not only was the mathematics done there new, vigorous, and bo l d, but (what was, and too often is s till unusual) the Institute also did outstanding work in both pure and applied mathematics It was far ahead of other mathemat ic s department s and gave serious attention to numerical meth ods for solving difficult differential and integral equations. The painting and its new title were intended to stimulate discus sio n, starting with the obvious question: there are two female figures-which one represents pure mathematic s and which one represents applied mathematics? The question can be argued either way. The woman without clothes could be identified with carnality, with the physical as opposed to the spiritual side of life, and therefore represent s applied sc ience, while the clothed seri ou s, brooding woman represents as cetic values, di vorce d from earthly concerns, and thereby represents pure science. On the other hand we could argue that the absence of clothing and the upward ecstatic glance toward heaven represents purity while clothing ( notice that the clothes are coarse and drab ) represents earthly values and that the clothed woman's dour, downcast look represents the Copyright ChE Di u ision of ASEE 1998 14 Chemical Engineering Education

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... chemical engineering is not an isolated subject; .. .it is not limited to applied science, but rather is a significant part of daily life, related to health, to human relationships, to politics and sociology and law, to the way we think and feel about ourselves as individuals and as members of society, to our aspirations, our hopes and our fears. applied scie nce s that must deal with daily realities. Titian 's painting shows that there is a unity in opposites, an old idea in philoso phy : truth and ultimate reality are revealed to us in a variety of faces. In today 's world, we talk about unity in diver s ity we read book s about the increasingly simi lar roles of male and feFigure 1. Sacred and Profane Love, by Titian In the Mathematical Sciences Institute of the University of Gottingen it was retitled Pure and Applied Mathematics. I can best illustrate the practical and also deeply human basis of chemical engi neering by recalling a revealing anecdote from a late col league, Pro fessor Irving Fatt, in Berkeley's optom etry department. He asked his class, Who is respon si ble for the multi million dollar con tact lens industry? male and we profe ss the virtues of blending Ea s tern and Western cultures. Sacred and Profan e Lo ve (or Pur e and Applied Mathematics) illu s trate s the fuzziness, the growing disappearance of borders between intellectual categories. It s how s what is increas ingly recognized in univer s itie s today-that while uni versity department s may be nece ssary for efficient ad mini s tration intellectual concerns no w overflow depart mental divi s ion. Intellectual concepts are increasingly delocalized as the interests of faculty in one department overlap those in another. My claim, that chemical engineering is one of the humani ties, goes beyond the by-now clear evidence that contempo rary chemical engineering is increa si ngly related to a variety of other phy s ical and biological sc ience s. What i s only slowly becoming apparent is that chemical engineering is also clo se l y related to the soc ial and hum a ni s tic "scie nc es," where "sci ences" is now in the original se n se of "scientia"that is, not nece ssar ily natural sc ience but more genera ll y, knowledge in all of it s varieties. This close relation s hip follows from both practical and intellectual trends in co ntemporary soci ety, as I shall now try to explain. The practical trend i s so fundam en tal that we are tempted to forget it: chemical engineers exist because society wants chemical product s that will satisfy hum an needs. Chemical engineering i s dri ve n b y society's wish for a better life where better i s not only materi a li stic, but also deeply hu man -as for example, in medicine and pharmacy for health in cosmetics for beaut y, and in agricultural chemicals for feeding a hungry world. Wint e r 1998 As usual initially there was s ilence followed by some s tudents shyly men tioning name s of prominent polymer scientists. "Wrong," replied Fatt, The father-more correctly, the mother of the co ntact len s industry was a poet, Dorothy Parker aut h or of the immortal line s, Men seldom make passes ... At girls who wear glasses."' Chemical engineers are driven into ever-new areas by the need s, often deeply humane needs of a so ciety that wants to improve it s quality of life Chemical engineers work not only to make girls more attractive, but also, for example, to make acid-free paper for preserving literary and hi storic documents, to make new drug-delivery systems for chronic illnes ses s uch as diabetes, to make special paints and gl ue s for restoring old paintings and archeological artifacts, to make new wound dressing s for severe burns, to make water-a b sor bing gels for diaper s and for providing mois ture to the roots of desert trees that yield not onl y fruit for food, but also shade from the brutal s un If the goal of chemical engineers i s to satisfy human needs, chemical engineers mu s t ha ve so me understanding of human na ture of p syc hology and international relations, of social organizations, and of the clash of cultures. Chemical engineers do not live or work in a vacuum. They must under s tand labor l aws, health insurance, safety, pollu tion abatement, a nd local customs and cultural values-in other words, the concerns of social scie nti s ts from econom ics to soc iology. But beyond that, a successful c h emical engineer must also understand how his product can either satisfy or offend his constituency; he must have some un15

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derstanding of the ever-so-complex human soul, and that inevitably leads him to his tory to psychology and to art-in short, to the humanities Both practical and intellectual trends in con temporary society make chemical engineer ing one of the humanities. The intellectual trend is not as evident as is the practical one but it is clear to anyone who is familiar with what literature art, and philosophy have em phasized for at least two generations: the dis solution of boundaries, the inter-relatedness of objects, phenomena, and observers. Noth ing stands alone. Any one thing is without end, related to many other things. Literary critics tell us that to understand a text, we must probe not only into the author's history and his state of mind when he wrote his text, not only must we consider the customs and prevailing values that existed when the text was written, but we must also probe into the reader's history and his values and his state of mind when he reads the text. Thus every interpretation depends on numerou s factors, including the color of the book cover and the type of paper used by the printer. In the limit, this critique leads to the infamous movement Deconstruction" where ultimately nothing objective remain s. The only remaining ulti mate reality is inter-relations. The dissolution of boundaries is strikingly evident in art. Figure 2 shows Escher's Night and Day Notice how the white birds flying to the right change, not abruptly but continu ously, to black birds flying to the left. The dissolution of boundaries extends not only in space, but also in time. Figure 3 shows a famous painting by Marcel Duchamp titled Nude DescendingStairs (An unsympathetic critic called this painting "Ex plosion in a Tile Factory.") We cannot localize the young woman; her fuzziness is not only spatial, but also temporal ; she is simultaneously at the top of the stairs and at the bottom A related idea i s indicated in a remarkably simple modem sculpture by my former gradu ate student, Dr. Bryan Rogers, who is now chair of the Art Department at Carnegie Mellon University. Bryan is probably the only person in the world who has a joint PhD in chemical engineering and in art. Figure 4 shows a set of clocks as found in any interna tional airport. But the usual designations, e.g., 16 Figure 2. Night and Day, by Escher Figure 3. Nude Descending Stairs by Duchamp Figure 4. Berkeley, by Rogers BERKELEY BERKELEY BERKELEY BERKELEY BERKELEY BERKELEY BERKELEY BERKELEY Chemical Engineering Education

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New York London Tokyo Mo scow, etc., have all been replaced by Berke ley We see here the idea of inter-relat edness. No place i s i so lated; what hap pen s anywhere in the world, happen s also in Berkele y. Twenthieth-century philo so pher s like Heidegger and especially hi s German di s ciple Georg Gadarner and to some extent his American admirer Richard Rorty have emphasized the importance of context and contingency. The significance and effec tivene ss of any object lies not in itself but in how it interact s with it s environment. This fundamental idea ha s greatly influ enced recent and current work in hi story, )jterature economics-in just about every social science and humanitie s department in every major university In )jterature hi s tory anthropology, so ciology law, busine ss administration, etc., emphasis is increasingly placed on inter relation s hips on how one s ubject is re lated to another-in other words, on con text. Historians of art are not only looking at what artists were doing at the time when a particular painting was created; they are also looking at the social relation s that artists had with each other and their pa trons, at the political climate of the time at the literature of the day at religiou s practices and conventions, and at the mechanism s artists used to publicize and market their work. Researchers in bu si ness administration are no longer primarily concerned with the internals of a cor[We must] show students how technology is related to human needs, both personal and collective; how applied science is a response to human aspirations and how it often is not just a consequence of, but also a stimulus to, pure science; and how the concerns of what men and women want and need drive the academic programs for all departments on campus. Like everyone else at a scholarly institution, engineers or philologists, chemists or economists, physicians or theologians, we strive toward a better understanding of ourselves and toward a more noble life. For chemical engineering education, the essential role of context should not be del egated to courses in humanities. To be truly effective they can easily be integrated into the present chemical engineering curricu lum It takes only a little time to show s tu dent s how chemical scie nce s relate to the world around u s. Toward that end, the main requirement is an open-minded attitude by instructors, a wirnngness to depart from that confined area where they are expert and feel totally secure and to devote a few minutes to related areas where they are not expert but where the relevance of their subject lies and where they as role models, can show humanity and openness to the world rather than the confinement of a narrow spe cialty. All too often the image th a t fac ulty present is such that only the instruc tors' expertise i s visible, while their di verse talents interests, passions, and weaknesses-in s hort their humanity remain s hidden No wonder that so many st udent s think of faculty as a s pecie s se pa rate from the rest of humankind! The regrettable bifurcating mind of many faculty was aptly described in a short story by the Italian writer Ignazio Silone In this story the wife of a professor talks about him and gives the concise description Oh he knows everything But that' s all he knows." When we present the principles of refrig eration, we usuaJly take a few minutes to discuss the desirable properties of refriger ants, including freons At that time it is a poration, but instead with how the corporation relates to the community, with health and safety matters with how corpo rations interact with other corporations with government, and with soc ial groups representing a variety of religions and ethnic tradition s. Mathematical economists are inter ested not only in cash flow, taxe s, and interest rates, but also in so-called externalities, including p syc hological factors, tastes, fads, fashions, perceptions and the persistence and decay of myths and folklore. simple matter to talk briefly about how some freons attack the ozone layer that protects the earth from excessive ultra violet radiation and to indicate the need for synthesizing new compounds that can serve as environmentally ac ceptable refrigerants. To iJlustrate the principle s of heat transfer we need not confine attention to the time-worn double-pipe heat ex changer. Along with the usual equations for conduction, convection, and radiation, we could also talk about solar energy, coo)jng requirements for supercomputers, heat ef fects in reentry of s pace vehicles, cryosurgery, and such home-related topics as microwave ovens, fire-resistant paja mas for infants, or design of an effective fireplace. No objects or subjects exist by themselves, but always in relation to other objects or s ubject s. Chemical engineering, by itself, has no value. The value and legitimacy of chemical engineering arise only when it stands in relation to some thing else toward satisfying some human need toward answering a question of deep human concern. Chemical engineering is an applied science in detail, but it is a humanity in intent. Winter 1998 When we talk about flowing fluids, let 's mention check valves, rupture disc s, human failures, and the tragedies at Bhopal in India and Chernobyl in the Ukraine. When we discuss condensers, let 's mention fog at airports. When 17

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we derive colligative propertie s of so lution s, let's talk about salt for removing snow on our streets and then about subsequent corrosion of automobiles. When we discuss evaporation, let' s mention desalting of sea water and the drought in Ethiopia. When we encounter the free en ergy of formation of ammonia, let' s also say so mething about fertiliz ers, a bout starvation in Somalia and perhaps a few words about the latest farm bill passed by Congress. Further, let's recall for our students that ammonia is used for making nitric acid, that nitrate s are used for making explosives, and that if Fritz Haber had not invented his synthetic-ammonia proce ss early in thi s century, Germany would have run out of ammunition in 1915 and would have been un able to continue World War I af ter the first year. a lready providing incentives to encourage teamwork in re search, better cooperation with industry, team teaching in terdisciplinary co ur ses, and lowering of departmental barri ers-in s hort toward integrating engineering ed ucation and research with those broad areas that engineering se rves. Funding agen cies now prefer research proposals that are problem-oriented to be conducted not by separate investi gators but by a team of sc holars from severa l disciplines. At the same time students and parents are demanding that more attention be given to courses that emphasize "w hy instead of how ," that s tres s overall purpose rather than details of method, and, as a per ceptive undergraduat e at the Uni versity fo Roche ster said, "to courses that give fewer sca le s and more music." I mention these examples not only to stress the relevance of chemical engineering, but also to suggest that when taught with gen erosity, chemical sciences can serve as an integrating factor for under standing our living world as de scribed in newspapers television and history books Figure 5. As it prepares for the ne xt cen tury, every chemical engineering department faces two challenges. The first one is well known and relatively sim ple : to keep up with impressive new developments in scie nce and to make them relevant for practice. Surely that is one of the traditional goals of engineer ing. It i s likely that essentially all chemical engineering depart ments will meet this first cha]To prepare st udent s properly for meeting the expanded expectations I and My Village by Chagall of society, faculty can no longer restrict their undergraduate courses to narrow specialization with the comfortable thought that the student's "o ther educational needs will be supplied on the other side of the campus. The re s ponsibility for good education cannot be so easily compartmentalized. There i s a crucial difference between the words integrated and sepa rate but equa l, as the U.S Supreme Court decided about forty-five years ago. If we believe-and I s u spect that we all do believe -that engineering is ultimately not merely a technical but also, essentially, a human enterprise, then we are obligated to communicate that belief to our students in a consistent way. We cannot meet that obligation by merely requiring our students to attend an occasional course in history or anthro pology or whatever. If we are to be consistent in our purpose then it is our task, in our own courses, to s how the intimate continuity between applied science and ulti mate human concerns. Pressures from government and its funding agencies are 18 lenge with s ucce ss. The second and more difficult, challenge is to humanize the curriculum, not through new courses but by introducing into existing technical courses the human dimen sio n; to show s tudent s how technology i s related to human need s, both per so nal and collective; how applied sc ience i s a response to human aspirations and how it often i s not just a consequence of, but also a st imulu s to pure scie nce ; and how the concerns of what men and women want and need drive the academic programs for all departments on campus. Like everyone else at a sc holarl y institution engineers or philologists, chemists or economists, physicians or theologians, we s trive toward a better understanding of ourselves and toward a more noble life. In our relations with students and faculty in other departments, let u s not be se parated by our differences but joined by our common purpo se I plead for teaching this commonality of purpo se not only because it is fashionable to reverse the alarming trend of the univer sity to a multiversity. My plea is motivated by two equally important goals. Chemical Engineering Education

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First, if we humanize our curriculum we produce better engi neer s, we rai se the pre s tige of e gineering, and we help to combat the threatening anti-science and anti-technology movements that are growing in our alienated popu lation Engineer s must increa s ingly communicate, to li s ten with empathy to tho se who do not un,,.( l \ ) j n+l n n-1 distillation we look at one plate in the di s tillation column and then write mass balances for all flows that en ter or leave that plate. In this exer cise we forget not only the rest of the distillation column but also the entire chemical plant and the com munit y that it serves. I am not opposed to free-body dia der s tand or who are frightened by new technology and to speak to them effectively, leading them toward confidence and trust. Good skills in English are not MATERIAL BALANCE grams nor do I s ugge st that we re frain from u si ng them in instruction. Free-body diagram s constitute a Ln+1 + Vn-1 = L" + V" pedagogical tool that has been and continues to be valuable for effecenough. The engineer must also tive education. But free-body dia have some understanding of hi s audience; in other words, he need s to understand the human dimension s of hi s work. In the V = VAPOR FLOW RA TE t grams convey an attitude, a philo sop hical viewpoint that is seriously incomplete. We sho uld not abandon free-body diagram s, but we s hould not re str ict engineering education to the attitude that they imply I plead for a s hift of balance where we rely L = LIQUID FLOW RA TE world now emerging, an Ameri can engineer must know how to communicate, to listen and to Figure 6. Free-body diagram for plate n in a distillation column. speak, with a peasant in India a rabbi in Jerusalem or a lawyer in Washington. Second a chemical engineering department i s not a trade sc hool. A worthy chemical engineering department is not content to limit its educational efforts toward producing robots for industrial employment; it strives to produce thoughtful sensitive, and independent-minded graduates who are not only competent engineers but also well educated individuals, prepared for fulfilling lives both inside and outside their profe ss ion. To achieve this edu cational goal, engineering faculties mu st integrate and interrelate what we do in engineering with the greater world that engineering aims to serve. Toward explaining my conviction that engineering is an integral part of our spiritual as well as our physical exist ence, I have shown examples from seve ral artists. Finally, I would like to show one more : a well-known painting b y Marc Chagall, painted about seventy-five years ago when Chagall was a young man remembering his childhood in rural Russia. In a sense it is an autobiography. It is called/ and M y Village (Figure 5), and it indicates the influence s that made Chagall the particular individual that he was at that time It shows a set of memories that are separate, yet integrated to form a harmonious continuum. Contrast this painting with the essential image we use to teach applied mechanics-the free-body diagram. In a free body diagram we isolate the essentials of our focus of study, we neglect the surroundings, and we ignore the context. In teaching chemical engineering, we also use free-body diagrams. For example, as shown in Figure 6, in teaching Wint e r 1998 not only on the i so lated specifics but also, as suggested by Chagall 's painting give attention to the larger view, toward awakening engineering students to see both the leaves on the trees and the forest the mountain s and the cities, and the hum an beings that li ve in them. To illu s trate this s hift of balance to help our students broaden their professional horizons and to attain more mean ingful live s, it may be useful to recall a well-known (possi bly true) s tory concerning the great physici s t Niels Bohr. Bohr a distinguished profes sor of phy s ic s at the Univer sity of Copenhagen liked on occasion, to retreat to a modest cabin in a nearby forest where he could read and think without interruption. But an enterprising journalist discov ered thi s cabin, and wanting to interview Bohr knocked on the door. Bohr opened the door and the journalist entered. When he did so, he noticed an old hor ses hoe nailed to the door frame. Surprised, he sa id to Bohr "Yo u are a great sc ienti s t. Surely you are not s uper s titiou s. Surely you do not believe that a horseshoe can bring good luck." Bohr an swered without hesitation Of course I do not believe that. But I have been told that a horseshoe can bring good luck even if you don't believe it." Thi s charming story tell s u s once again that even for a great scie ntist life has a stro ng non-rational component and that we are all human being s s ubject to the hopes and fears that characterize the human condition. Let us reflect this duality when we teach our students science and technology Let u s not rely on others to do what we owe to the young men and women entrusted to our care. Let us show by our example and in our clas sroo m s, that engineering, in particu lar chemical engineering is also one of the humanitie s. 0 19

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.,~. 111 5 1111111 3..._c_l_a_s_s_r_o_o_m __________ ) COMET An Open-Ended, Hands-On Project for ChE Sophomores MARK R. PRAUSNITZ Georgia Institute of Technology Atlanta, GA 30332-0100 "Georgia Tech was the site of intense competition Monday, but this time it was not Olympic athletes who sought gold. Instead, eleven determined teams made up of chemical engineering majors met in quadrant two of SA C's main gym to embark on a battle of wits .. .. Kamikaze team member Heather Ledbetter explained how her team's COMET operated: "Our COMET stores elastic potential energy by displacing a spring. This potential energy is then converted to work, acting on our projectile-an egg ... The peeled egg worked the best.,, S ophomore chemical engineers at Georgia Tech re cently built Controlled-Operation Mechanical Energy Transducers (COMETs) as part of a project to intro duce them to a number of important engineering concepts that are often not addressed until later in the curriculum if at all. In the COMET competition student team s designed, built and used simple, self-powered device s that indepen dently traveled to a designated location. While electrical and mechanical engineering students fre quently participate in design competitions involving stu dent-built machines, [IJ chemical engineering students' hands on experience is usually limited to prefabricated laboratory experiments during the junior or senior year. To introduce activities other than pencil-and-paper homework assignments earlier in the curriculum, development of hands-on design projects appropriate for beginning chemical engineers has recently received increased attention Y 31 Motivated by this concern, I developed and offered the COMET competition Mark Prausnitz is Assistant Professor of Chemi cal Engineering at Georgia Tech. He was edu cated at Stanford University (BS 88) and MIT (PhD '94). He currently teaches mass and en ergy balances to chemical engineering sopho mores recently spent a year teaching biomedical engineering in developing countries with ORBIS International and has taught public speaking for more than ten years He conducts research on novel mechanisms for improved drug delivery by controlling tissue permeability using electric fields ultrasound and microfabricated devices. spectator gallery COMET launching area barrier (6' tall x 6' wide) t:et -40 -5 0 35' 5' Figure 1. Schematic of the COMET competition arena located on an indoor basketball court. COMETs traveled by land and / or air from a launching area, around or over a large barrier, and to as close to a target location as pos sible. The COMETs were designed and built by teams of sophomore chemica l engineers in two consecutive sophomore-level classes on energy bal ances.[41 It was designed to achieve the following goals: Teamwork Students formed teams of two to four mem bers who worked together on all aspects of the projects. Open-Ended Problem Because there were few rules in the competition, many possible designs could accom plish the assignment. Design Given only a spending limit and a final goal, Excerpt from a final COMET r e port written by a team of students had to design, build, test, and use their COMET. students -----------------------Co p y righ t ChE Divi sion of ASEE 1998 20 Chemical Engineering Education

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Hands-On Experimentation Because a successful COMET design depended largely on empirical physical testing, students needed to get their hands dirty. Technical Writing Each group prepared a final report that described and analyzed the design of their COMET, including written text, figures and calculations. Estimation B ased on Limited Data Quantitative esti mates of kinetic and potential energies were required in the final report. Students designed and performed addi tional experiments to calculate rough estimates of those energies. THE ASSIGNMENT The COMET project had few rules, thereby giving stu dents the opportunity for creative design In groups of two to four students, each team designed and built a COMET that could be launched from a designated lo cation and without human inter vention after launching, would come to a stop as close as pos sible to a target location approxi mately forty feet away (Figure 1) To make the assignment more challenging, a large object was placed five feet in front of the target so that a straight path to the target would be blocked The COMET had to cost less than $20, measure less than one foot in all dimensions, have no elec trical, chemical, or human power sources, and be safe. The COMET could have a separate launching unit of any size, but the launching unit had to remain behind the starting line. The assignment was given to the students two to three weeks before the competition. Immedi ately before the assignment was given, we held an in-class brain storming ses&ion to help students think broadly about the project. We identified possible paths an object could follow between two points separated by a barrier and considered ways in which an ob ject could be powered to follow some of those paths. One week before the competi Wint e r 1998 tion a preliminary design of the proposed COMET and its expected course was collected to ensure that each group had s tarted work on the project. I provided feedback on these preliminary designs, commenting on approaches that seemed overly complex, unlikely to work, or unsafe. Students also received sample energy balance calculations to guide them in preparing their reports, as described below Optional prac tice sessions were held before the competition so that teams could test their COMETs in the competition arena. THE COMET COMPETITION The competition consisted of three rounds. During each round, each team in turn launched its COMET toward the target (see Figure 2) The referees (i.e., class TAs) measured the shortest distance between the target and the COMET. Figure 2. COMETs being launched at the competition. (A) The Tom ato" team shot a rice-filled balloon from a rubber band-powered cannon. (B) The Quadrangular" team COMET drove to the side of the barrier and then made a 90 turn by triggering a second se t of wheels. (C) The Slinger s" launched a putty-based COMET from a slingshot. (D) The Spartans vehicle followed an arced path around the barrier and was powered in part by a rat trap. 21

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After the third round, the teams were ranked by aggregate score from all rounds of play. Members of the winning team each received a sma ll trophy. totaled under $20 as required in the assignment; some amounted to just a few dollars. Students performed energy balance calcu lati ons for eac h The ability of the COMETs to reach their target ranged from reproducibly having no net movement to reproducibly l anding and stopping within inches of the target. Most designs were based on potential energy stored in the form of a spri n g or rubber band that was used to catapult an object through the air. Others used the potential energy of gravity to move the COMET either on the gro und through the air, or a combination of both. Designs ranged from store-purchased pro jectiles modified for the competition to home made vehicles, some with complex and clever mechanisms to control the COMET's direc tion and speed While the complex designs were fun to see, they were generally unr eli able and yie ld ed only average performance. The winning designs in both of the COMET competitio n s were either a rocket or an arrow launched from the ground at a predetermined angle with a reproducibly applied force and having a mechanism to prevent rolling or bouncing once the COMET hit the ground. THE FINAL REPORT Although the competition was the highlight of the COMET project, grades were deter mined from each team's final report. The re ... ControlledOperation Mechanical Energy Transducers (COMETs) ... part of a project to introduce [sophomores] to a number of important engineering concepts that are often not addressed until later in the curriculum, if at all. In the COMET competition, student teams designed, built, and used simple, self-powered devices that independently traveled to a designated location. phase of the COMET's travel. A representa tive example follows, taken from the "Ber noulli Bunch" group's analysis of a COMET that was shot into the air from a rubber-band s lin g s hot landed on the gro und and finally bounced and rolled to a stop. First, these st dents estimated the elastic potential energy of the rubber band by s h ooting an object of known weight straight up into the air. They measured the maximum hei ght of the object and, assum ing no friction with the air, set the elastic potential energy lost by the rubber band equal to the gravitational potential energy gained by the object. They determined this energy to be 1.4 J. They then calculated the COMET's ve locity to be 11 mis upon leaving the rubber band launcher by setting the COMET s ki netic energy equal to the potential energy lost by the rubber band. Us in g energy balances applied when the COMET reached its maxi mum height first hit the ground and finally stopped, they determined at each point the COMET's kinetic a nd potential e n ergy, as well as its position and velocity ASSESSMENT OF THE PROJECT port was due two days after the compe tition ----------- From the instructor's perspective the COMET project accomplished the six goals for which it was designed. Students responded well to the teamwork environment and seemed and co n sisted of four parts : 1 A schematic diagram and description of the COMET 2. A sketch and description of the intended course the COMET wou ld follow 3. Receipts for items used to build the COMET 4. Quantitative energy-balance calc ulation s for each phase of the COMET's travel Grading was based half on clear, concise and neat presen tation and half on e n ergy balance calculations. Quality of COMET design and construction and the COMET's ability to reach the target did not influence grades as long as each team had made a reasonable effort to do well. The final reports were generally clear and well written and they provided reasonable analysis of the energy bal ances associated with the COMET's travel. The sketches of the COMET design a nd its intended course were mostly simple, hand-drawn diagrams (see Figure 3) s upported by one or two paragraphs of descriptive text. The receipts all 22 to share gro up responsibilities. They also approached this open-ended design project with an open-minded attitude as demonstrated by the many different types of COMETs built, most of which worked well Students spe nt a lot of time building and testing their COMETs which indicated they enjoyed the opport unit y for hands-on learning. The final reports contained adeq u ate technical writing and data analy sis, topics that are addressed more thoroughly in later classes To assess student opinion of the project a brief anony mous surveyf 5 61 was given a week after the assignment. It revealed that students generally found the COMET project to be educational, enjoyable, and worth repeating. Figure 4 shows student responses to the three specific questions asked. Students also provided written comments, which are sum marized below The average scores shown in Figure 4 indicate generally favorable responses by the students, but not enthusiastic endorsement of the project. This observation should be tem pered in two ways First a large standard deviation is associ ated with each average, largely due to a few students who Chemical Engineering Education

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/ c.omet Cou.'f.se ', ,J c. ome t Figure 3. A sample student sketch of the intended course the COMET would follow to the target (abov e ) and a schematic diagram of the COMET launching unit (below) from the COMET Busters team final report. 2 3 4 5 learning enjoyment 1 ;,., If----~--~--' use again? Figure 4. Student assessment of th e COMET proje c t. Based on anonymous responses from 28 students (solid bar) and 34 students (grey bar) in two different classes averag e s and standard d e viations ar e shown for re sponses to the following : Rat e y our l e arning from the COMET project (1 waste of tim e" to 5 vezy v alu abl e ") ; Rate your enjoyment of th e COMET project (1 dull to 5 lots of fun ); Giv e y our recommendation on using the COMET project again (1 absolutely not to 5 "absolutely yes ) Overall students found the COMET project to be educational enjoyable, and worth repeating (see text). Winter 1998 were unhappy with the project and rated it with a 1 or 2. The vast majority of students gave ratings of 3 and higher on all three questions If the averages were recalculated without the two or three dissati s fied students in each class, all three questions would have average values above 4 Second the s core s from the first cla ss were consistently higher than s cores from the second cla s s. Based on student comments, this difference is largely due to greater time pres s ure: the second class received only two weeks to work on the project while the first class received three weeks. Some representative student comments are provided be low followed by a discussion of what these comments say about the successes and shortcomings of the COMET project. Enfoyable Proiect Thi s i s th e onl y p ro j ec t I h ave h a d a t T ec h t hat w as e njo y abl e. I didn t ev en fee l lik e I w a s d o in g a proj ec t for a g rad e. " Fun proje c t bu t s till l ea rn e d a l o t ." Many students enjoyed the project. They were surprised to find that something educational could also be fun. Making the connection between academic values (i. e ., learning) and personal values ( i. e fun ) may be the most important lesson of the project. Student-perceived relevance of course mate rial i s known to be impo r t a nt for effective learning 1 7 8 1 Hands-On Learning It was n i ce t o d o so m e th i n g in Ch E a w a y fr om pap e r and th eory ." H o m e D e p o t i s ve r y f o nd of G e or g ia T ec h s tudent s." A number of students commented on the hands-on nature of the project and appreciated it as a refreshing change from conventional problem set s. The opportunity to exercise right-brain thinking through an active process that yields concrete results appeal s to s tudents with learning styles not easily accommodated in conventional left-brain" classroom lectures. C 9 l Weak Connection with Course Material /don t think I r e all y l e arn e d an y thing from the proje c t that p e rtained to th e c ours e. " I'd s u g gest allo w in g c h e mi c al e n e r gy sources After all, this i s a Chem E clas s. Some students were concerned that the project was not closely related to the rest of the course material. I partially share this concern While the quantitative energy balance calculations required in the final report relate directly to material presented in lectures the design, construction, and testing of COMETs are not as closely linked to the rest of the course. Nevertheless I believe it is important to expose engineering students to concepts like teamwork, open-ended design problems, and hands-on experimentation, and I think the COMET competition provided an exciting framework --------------Continued on page 45. 23

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.ta.-5 111111 3.._c_l_a_s_s r o o m ________ __,.) ANIMAL GUTS AS IDEAL REACTORS An Open-Ended Project for a Course in Kinetics and Reactor Design E RIC D. CARLSON, ALICE P. GAST Stanford University Stanford CA 94305-5025 E ducational researchers hav e identified a need to ex pand the typical teaching approach found in most engineering courses beyond the lecture and probl em set format. Lil Strict adherence to thi s traditional teaching method has several shortcomings. First, students po ssess a variety of learning styles _l2 1 Educational research ers have attempted to correlate learning s tyle s with traits s uch as Meyer sBrigg s Type lndicators,l3 41 gender, 1 5 1 and region s where the students grew up .l 6 1 By implementing only one teaching method educators can lo se so me of their audience and place so me stu dent s at a disadvantage. Second tradi tional teaching methods often do not promote the creativity desired by most employers and researchers. Third, tradi tional methods of teaching do not necessarily encourage s tudent s to develop the se lf -re liance essential in an indu stria l job or in graduate research In the "rea l world," problem s do not come out of a book numbered and self-co ntained nor do they proceed directly from the previou s day s lectur e. Ulti mately graduates need to be able to define their own prob lems and to determine what information is needed to so lve them Finally, engineering problems se t s do not emphasize the importance of communication. In thi s paper, we present an open-ended project tailored for a senior kinetics and reactor design course. The project i s based on work by Penry and Jumars in which basic reactor design equations are u se d to model the digestive system of several animalsP 1 We will begin by describing the assign ment, will follow with the results, and will close with some overall conclusions about the s ucce ss of s uch a project. THE ASSIGNMEN T We asked the students to model the dige s tive system of an animal of choice as one or more ideal reactors, applying principles from the course. There are three aspects of the project, each with its own goal: a literature search, the development of a model, and the communication of the model to an audience. While the project i s intended to be open-ended, st udents in general do not respond well to nebulou s assign mentsl 8 1 so we gave them our concrete expectations at the very beginning including specific goals to attain for each aspect of the project. We asked each stu dent to choose hi s or h er own individual animal, thus ensuring that each model would be unique Individual choice a l so a llow ed the st udent s to apply the project to an animal they found personally interesting. The first pha se of the project focused on searching the literature. To build a theoretical model of th e ir animal s digestive s ystem s tudents had to acquire information about the diet (reactant feed), the dige s tive process gut size (reac tor volumes), throughput s and any enzymatic and bacterio logical kinetic rate data from the literature Not surprisi ngly there is an abundance on literature information of so me animals, but very limited information on others We recog nized that some st udent s would find thi s di spari ty frustratEric Ca r ls o n is a chemical engineering PhD candidate at Stanford University studying the optical-rheology of elastomeric polypropylene with Prof Gerald G. Fuller. He earned his MS from Stanford University and his BS from North Carolina State University where he was intro duced to the joys of cooperative learning. On the few occasions he escapes from the lab he enjoys mountain biking rollerblading volleyball and poor attempts at golf . l:1 11 1111 ~, ,_ lfl!!.,".-. 1 =-ii( .; ~ A lice Gast is Professor of Chemical Engineer ing at Stanford University She obtained her BS from the University of Southern California and her PhD from Princeton University Her research interests i n complex fluids combine statistical mechanical models of suspensions and solu tions with neutron X-ray and light scattering experiments. Among other activities, she enjoys regular trips to the San Francisco Zoo and Monterey Aquarium. C o p y r ig h t ChE Di u i s i o n o f ASEE 199 8 24 Chemical Engineering Education

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In this paper, we present an open-ended project tailored for a senior kinetics and reactor design course. The project is based on work by Penry and Jumars in which basic reactor design equations are used to model the digestive system of several animals. TABLE 1 Dige st ive Schemes An im a l s display a variety of digestive schemes to handle avai labl e food so ur ces Single reactor sc h emes can model simple an im als with minimal energy r eq uir ements, lik e s tarfi s h. Larger anima l s with hi g h er energy requirements offer a l arger variety of digestive sc h emes. Sim l e Stomach Ca rni vores, frugivorous primates, and S mall Intestine om niv oro u s hum a n s all possess a --------':2 ~ ~ V simple stomach and small intestine to break down high-energy food. Some a nim a l s rely o n more readily avai l ab l e lower-energy foods suc h Comp lex, Multi Cha mbered Stomach To Small Intestin e Foregut Fermenter as grasses and leaves These animals generally need the assistance of microbes to break down food to provide energy. Fo r egut l"ermenters are animals in which microbial fermentation of ingested material precedes catalytic digestion (e g., cows, sheep goats deer hippos, kangaroos, wha l es, and manatees). Microbial fermentation takes place in a well mixed rumen or comp l ex stomach, af t er which th e foo d passes to a l ong, tube-like intestine w h ere catalytic digestion occ ur s In hind g ut fermenters (e g. horses rhin os, koalas, r a bbit s and elepha nt s), microbial fermentation takes place in the cecu m fo ll owing catalytic digestion. (} ,-::: Hindgut Fermenter ing, but we hop e d they would tolerate it and rise to the challenge once we explained the relevance of open-ended literature searches to their education. On a mundane level students learned how to perform on-line searc hes and to effective l y use the WWW how to find and explore appropri ate librarie s, a nd what type of information is found in texts as opposed to journal articles. At a higher level, students learned how to se lect relevant facts from a large, perhap s overwhelming, body of information. We asked that the s tu dent s tum in a concise s ummary of the relevant aspects of at lea s t three references. Winter 1998 The ne xt phase of the project was model de ve lopment. We asked the st udent s to ske tch the ideal reactor se rie s em ployed and to pre se nt the equations used to predict conver sio n s and residence times. This portion of the project al lowed students to apply course knowledge to a new prob lem that they devised for themselves. Based on their l i terature searc h they had to decide what reactor or reactor series was a ppropriate where there was essentially continuous flow, whether mixing was ideal, and what reaction s were impor tant. If experimental data were available in the lit erature, model predictions were to be compared with experimental val ue s of conversions and re si dence time s. Generally ki netic and conversion data are not avai l able for most animal s pecie s, so s tudent s were asked to fill in the gaps with appropriate assumptions by extrapolating data from other related s pecie s. In cases where s uch extrapolation was not feasible, st udent s were asked to describe in detail how one might experimentally gather kinetic data on the digestive system to compare with their model. Along with the model s tudents were asked to provide a critique, discussing the s trength s and weaknesses of their analysis, and to de scri be how well it would serve to predict reality. The critique forced the students to think about the equations and to understand the assumptions that go into them at a high enough level to be able to explain it to others. The l ast as pect of the project was the development of communication skills. In addition to the s hort summaries of the literature articles, stu dent s had to prepare a written report describing the model of their animal's digestive system, including an introduction motivating the application of the model to their animal. A small class s ize also allowed th e s tudent s to make oral presentation s of their report. The emphasis of the oral and written reports was on organizing a coherent presentation of the model its moti vation, and its critique. GUT MODEL DEVELOPMENT As s tated in the introduction, this project is based on Penry and Jumar s' work u sing basic reacto r design equations to model the digestive system of a variety of a nimal s and to identify the digestive operating systems that optimize th e utilization of nutrient s and the production rate of energy.'7 1 Their reactor de s ign model s and basic kinetic rate expres s ion s can be found in mo s t undergraduate kinetics and reac tor design textbooks,l 9 1 2 1 making the development ideal for 25

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use in the classroom. The authors discuss modeling the guts of marine deposit feeders, mammalian hindgut fermenters and mammalian foregut fermenters ( s ee Table 1). In their analysis the authors assume that digestive reac tions are homogeneous, kinetically controlled enzyme pro cesses in which food component A binds reversibly to en zyme E and dissociates irreversibly into product(s) P and free enzyme: A+EHEA P+E (1) They further assume that all digestive reactions fall into two main categories. Digestive reactions catalyzed by an animal's own enzymes are described by the Michaelis-Menton kinet ics and follow the rate expression where C A c oncentration of A V ma x ( 'sC E) K M 0< 1+k 2 ) /kl (2) Digestive reactions that rely on microbial fermentation are autocatalytic. Microbes M are produced as food component A is broken down. This can be described by A+M H MA P+M+M (3) Such reactions have an additional dependence on the con centration of microbes, CM: Ym a xCACM -rA = KM +CA (4) Reactor design textsr 9 1 2 J derive design equations for the three ideal reactors used in the gut analysis of Penry and Jumars: batch reactors, plug flow reactors (PFRs), and con tinuously stirred tank reactors (CSTRs) The time in a batch reactor or space time ( 't = v / v) in a continuous flow reactor required for digestion to achieve a particular conversion, X, can be found using the familiar design equations < 1-, -0 u< I Xfin a l B a t c h t = AO f !~ 0 PFR CSTR where -r A reaction rate N AO initial number of moles of reactant A C A 0 feed concentration of A V reactor volume v volumetric flow rate of the feed ( 5 ) { 6 ) ( 7 ) Figure 1 shows the graphical design equation for finding the space time of an animal gut performing a catalytic diges tion process following Michaelis-Menton kinetics To mini mize the space time, Michaelis-Menton catalytic digestion is optimized by a PFR design. Figure 2 shows a plot of recipro cal reaction rate versus conversion for an autocatalytic mi crobial fermentation process Autocatalytic reactions are op timized by a CSTR operating at the point of maximum reaction rate, followed by a PFR. Penry and Jumars suggest general designs for deposit feed ers mammalian hindgut fermenters, and mammalian foregut fermenters. Depending on the specific animal being mod eled, reactor design models may need modifications to ac count for various factors-such as variable flow rate, vari able gut volume, non-ideal mixing, recycling by means of coprophagy (reingestion of feces), and caecotrophy (reingestion of partially separated feces, as in rabbits)-and residence time distributions. Modifications to the reaction kinetics may account for different forms of enzyme kinetics, mass-transport limitations, heterogeneous catalysis, and non isothermal conditions. Ultimately fundamental reactor deTABLE2 Animals Students Chose to Model Foregul Hindgut Single Gut Fermenlers Fermenlers Hydra Cow Elephant Boa Con s trictor Blue Whale Rabbit Sea Anemone Hippo Hor s e Starfi s h Kangaroo Rhinoceros Conversion, X Conversion, X Vampire Bat Goat Koala 26 Figure 1. Graphical design equation for a plug flow reactor (PFR) Figure 2. Graphical design equation for a continuously stirred tank reactor (CSTRJ. Hummingbird Deer Manatee Chemical Engin ee ring Education

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sign eq u ations can form a biologically meaningful math ematica l framework for the description of animal digestion. STUDENT ANIMAL GUT MODELS Using the tools of kinetics and reactor de s ign and the ideas presented in the work of Penry and Jumars the class was able to develop models about the digestive behavior of ani mals across the animal kingdom Some animals had seem ingly simple digestive systems, while other s had more com plex g ut s. Table 2 li s t s typical a nimal s that students mod eled. A few of the animals were modeled with single ideal reactors (vampire bat sea anemone, starfish) and offered simple systems like the deposit feeders in the article by Penry and Jumars. Many of the animals required a ser ie s of reactors. A student model of the hippo gut (foregut fer menter; CSTR-PFR) is presented below Several students v=40 kg/day p=306 kg/nf Yc==0.46m 3 =0 15m 3 L=47m Figure 3. The familiar hippopotamus and a student model of th e hippopotamus gut v, {foregut fermenter; CSTR-PFRJ. Fine Particles Proximal Colon V =l 540mL t=lOlhrs extended their model to account for digestive behavior dis tinctive to their animal, u si ng either additional reactors or modification of the underlying assumptions Two prime ex amples are also presented below: a koala bear ( hindgut fer menter; CSTR-PFR-Separator-CSTR-PFR) and a manatee ( hindgut fermenter; CSTR-PFR-CSTR-PFR). Hippopotamus Hippos are foregut fermenters that spe nd about five hour s a day eating about 40 kg of short grasses. The student modeled hippo digestion with a CSTR and a PFR in series with information about the volume of the stomac h the length of the intestines, and the feeding rate from the literature_ l 13 J The model is s hown in Figure 3. The volume of the intestine was calculated based on data of the di str ibution of dige s ta between the stomach and the inte s tine s. Reactor volumes and throughputs allowed for the estimation of fairly reasonable residence times: 'tcsTR = 3.5 day s, 'tPFR = 1 1 days. The s tudent suggested tracer studies to check the accuracy of the se estimates. Detailed kinetic data were not available to calculate the actual conversions. The s tudent di sc ussed how one might get the kinetic information experimentally, either by monitoring hippo s in the field exami ning hippo excrement ,* or by extrapolating from a known body of data on animals with s imilar dige st ive systems (e.g. cows). Researchers could then use the de sign equations and compare calculated conversions with those found experimentally. Because the nightly feeding of hippo s only last s about five hour s, a more rigorou s model would account for the unsteady nature of the di ges tion proces s Koala Koalas are hindgut fermenters with a unique diet. Exceptionally picky eaters, koalas focus entirely on a select, low-quality food source-eucalyptus leaves from only about 5 of over 100 available s pecies. Koalas have evo l ved highly specific guts to digest this food source, a nd reac tor design analysis can give insight into the importance of nature 's design. X,. } Autocatalytic Microbial CA J Fe rmentation .---~ The contents of eucalyptus cells are highly diges tive according to the literature 1141 The stude nt as sumed that all dige s tion of the ce ll contents occurred in the stomach and s mall intestine by means of cata lytic digestion. Microbial breakdown of the eucalyp tus cell wall occurs only in the cecum and the co l on. Koalas are not born with these helpful microbes but rather gain them from ingesting adu lt feca l matter shortly after being weaned : SJ2lllB&h V=350mL t=47hr s Small Imestin e V=l35mL t=l8hrs Catalytic Digestion .-------,X.., C.::-oa:-=rs :::-e~~ 1__ ____ _J CA Particles Distal S2~9fs8mrtum Negligible Digestion Figure 4. Student model of th e koala gut (hindgut fermenter; CSTR-PFR-Separator-CSTR-PFRJ. Winter 1998 The model of koala digestion i s shown in Figure 4. On a field trip to the San Fran cisco Zoo the class learned of the availability of hippo exc rement ; hippos leav e the water to distribute their feces rather widely to mark their territory ** On the same field trip to the San Fran cisco Zoo, we learned of weaning and eating habits of young koalas. 27

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Literature provided the student with tracer and dissection studies of koalas that reveal two main residence times in the koalas' guts The mean residence time for particulate matter was about 100 hours, while that for the solute phase was about 210 hour s. The student decided to employ a separation process within his model to account for these two residence times. Becau s e koala eating is spread fairly continuously throughout the day between period s of sleep the student modeled koala digestion as a continuous process. Using this model and literature values for throughput rate and gut volumes, the student was able to match the experi mental residence times for both the coarse particles and soluble fine particles Unfortunately, the student was unable to find kinetic data for these reactions ; he pointed out that kinetic data would allow one to study the digestion of koalas with mathematical models and reduce the need for slaughter/ dissection studies. v C AI ----~ Small Intestine V=93L V=68L -r=42hrs -r=3 lhrs Catalytic Digestion processes. The only unknown variable is CM the concentra tion of microbes. For the purposes of calculating general trends the student assumed that the microbe concentration was directly related to the concentration of food C A. Now by examining each reactor in sequence one can calculate the output C A and conversion. Even with her broad kinetic generalizations the student found that the theoretical overall conversion fell between 60 % and 80 % comparing extremely well to the literature which cites 45 % to 70 % for manatees (and about 84 % for dugongs another species of sea cow). As weaknesses of her model the student cited several factors, including the lack of true kinetic data, the assump tions of constant volume digesta and complete mixing in the CSTR compartment s. Thi s model allow s one to conceptual ize the conversion of food however and illustrates the effi.---~ X ~ ----~ c ,.. C2i2n V=185L Autocatalytic Microbial Fermentation ciency of nature in de signing its own reactors. ANIMAL GUT DESIGN ASA TEACHING TOOL Manatee Another modification of Penry and Jumars' hindgut fermenter was presented by a student who modeled the guts of manatees. A scheme of four reactors was chosen to model its digestive be havior. The student de cided that Penry and Jumars model of a hind gut fermenter PFR-CSTR Figure 5. Student model of the manatee gut (hindgut f e rmenter; CSTR-PFR-CSTR-PFR) Students (and instruc tors) responded well to this open-ended project. It was enjoyable for ev eryone and it added a unique dimension to the class. As a teaching tool the project was a suc series was a poor choice in the case of the manatee for two main reasons: first manatees are known to achieve large conversions, and large conversions that operate beyond the maximum au tocatalytic reaction rate are inefficient in a CSTR, and second, the long curvaceous nature of the colon, coupled with the viscous nature of the digesta found in the mana tee makes perfect mixing unlikely Like horses and elephants, manatees use the cecum and colon as primary fermentation sites whereas the stomach and the small intestine are used for catalytic digestion Because both the colon and the small intestine are long and narrow they were both modeled as PFRs. The open cavities of the stomach and the cecum are more amenable to CSTR design. Thus, a CSTR-PFR-CSTR-PFR series was chosen to model the manatee gut, as shown in Figure 5. Equations of forms (2) and (3) were used to model the catalytic digestion and the autocatalytic fermentation reac tions respectively. CSTR and PFR behavior were modeled using Equations (5) and (6). The student was unable to find kinetic data specific to manatees, but she was able to find the typical range of rate parameters V MA X and KM found in hindgut fermenters for fermentation and catalytic digestion 28 cess on several levels. While the subjective nature of evaluating student performance makes it difficult to give direct quantitative comparisons with more traditional prob lem assignment s, there were several indicators by which we were able to judge this project s success. Foremost, it was obvious that students learned from this exercise The project allowed students to apply kinetics and reactor design concepts and to extend their knowledge of course material to a unique reactor system Based on their own knowledge, they had to decide for themselves what model assumptions were appropriate. The project saw the development of several fairly comprehensive models built to account for complex reactive and flow behavior. The in class presentations allowed students to present to and teach each other about the applicability of ideal reactor models. Not only was the project instructive, but it was also enjoy able to the students. Overall, student response was highly Stud e nts w e r e told from th e b e ginning that the proje c t would count for a non-trivial part of their grade Evaluation would b e based on proper u se of course material exhaustiv e ness of th e literatur e search completeness of the model based on available information and creativity rigorousness of th e critique and quality of oral and written presentations Chemical Engineering Education

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favorable. When asked their opinion of the course after wards, students responded that they "enjo y ed the project and that it wa s fun"-phra s e s rarely u s ed to describe a typical homework set. We did receive a few less positive response s at the begin ning of the project. While some student s liked the flexible nature of the project, a few students worried about what wa s meant by the project's s ucce s s being up to them. Several students were initially turned-off by the idea of an open ended literature search. We dealt with complaints about trying to chase down detail s that may or may not exist in a large body of literature in a case-by-ca s e manner. Ulti mately, the students developed s earching strategies and were ab l e to organize the information The open endedness of the project made creativity possible, which the students all seemed to enjoy. An additional success indicator was increa s ed office hour attendance Students who previously had not s hown exces sive interest in course material began arriving early and asking questions. Several became quite s timulated by the topic and would engage each other in di s cussion about their models. These discussions provided an effective cooperative learning environment in which students relied on each other to learn and to teach the subject matter. [1 1 Finally, students were both more creative in their problem solving and more expressive in the di s cu ss ion s of their mod els. This project was a succe ss a s a teaching tool becau s e its open-endedness and active learning emph a si s appealed to a wide variety of learning styles The open-ended project was comp lim entary to more traditional problem sets in that it allowed students to extend their knowledge beyond what had been directly presented in the classroom. CONCLUSIONS Reactor design models can be s ucce s sfully employed to model the guts of a variety of animal s, and the use of s uch models on unique animal s y s tems provide s a stimulating learning experience for both the s tudent s and the instructor. We would enco ura ge any one teaching a reactor design class to use this or a similar type of project to engage the students and help seize their interest. ACKNOWLEDGMENTS We would like to thank the students of ChE 130 from the winter quarters of 1996 and 1997 for their participation enthusiasm, and creativity In particular we would like to thank Sao Wei Lee for hi s model of the hippo gut Dhruv Gupta for his model of the koala gut, and Lani Miyoshi for her model of the sea cow gut. APG would also like to thank Deborah P enry for giving her the initial idea for this project at the 1st Annual Symposium on German-American Fron tiers of Science. Winter 1998 REFERENCES 1. Ro sa ti P.A. and R.M Felder Engin ee ring Student Re s p o n se to an Ind e x of Learning St y l es," Pro cee d i n gs1995 Fr o nt ie r s in Edu ca ti o n Conf e r e nc e, IEEE New York, NY, p. 7 3 9 ( 1995 ) 2. Felder R.M., a nd L.K. Silverman, Eng. Ed. 78 (7 ), 674 ( 1988 ) 3 My e r s, I.B. and McCaulley Manual : A Guid e to th e D e v e o pm e n t and Use o f t h e M ye rs-Br iggs T y p e Indicat o r Con sulting Psychologists Press Palo Alto CA ( 1985 ) 4 Rodman S.M ., R.K. Dean and P.A. Rosati, Learning Style Among Engineering Students: Self Report vs. Classification ofMBTI Pro cee din g s-1995 Fr o nti e r s in Education Confer e n ce, IEEE New York NY, 48 ( 1985 ) 5. Feld e r R.M K.D Forrest L Baker-Ward E.J Dietz, and P H Mohr, J Engr Ed. 82 ( 1 ), 15 ( 1993 ) 6 Felder R.M. P.H Mohr E.J Dietz, and L. Baker-Ward, J. Engr Ed. 83 ( 3 ) 209 ( 1994 ) 7 Penr y, D L and P.A. Jumars, Am e rican Naturalist 129 69 ( 1987 ) 8 F e lder Richard M ., Meet Your Students: 6. Tony and Frank ," Ch e m. En g r Ed ., 29 ( 4 ) 244 ( 1995 ) 9. Levenspiel 0. Ch e mi c al Reaction Engin e ering, 2nd ed Wiley, New York NY ( 1972 ) 10 Fogler F S El e m e nts of Ch e mical R e action Engin e ering, 2nd ed ., Prentice Hall New Jersey ( 1992 ) 11. Smith, J.M. Ch e mical Engin e ering Kinetics 3rd ed ., McGraw-Hill New York NY ( 1981 ) 12. Hill Jr ., C.G. An Introduction to Ch e mical Engineering Kin e ti c s and R e a c tor D e sign, Wiley New York NY ( 1977 ) 13 Cl e mens E T ., and G.M O Mallo y, J of Zoology 198 141 ( 1982 ) 14 Cork S J. I.D Hume and T J Dawson J. Comp. Physiol. 153 181 ( 1983 ) 0 t.A ... 5--....__b_o_o ___ k_ri_e:..._v_,_:e_w__:__ ______ ) INTRODUCTION TO THEORETICAL AN D C OMP UTATI O NA L FLUID DYN AM ICS by C. Pozrikidis Published b y Oxford University Press, 198 Madison Avenu e, N e w York NY 10016; $75.00 (1996) Reviewed by Michael D. Graham Univ e r s i ty of Wis c onsin Madison Introdu c tion to Th e or e ti c al and Computational Fluid D y nami cs is an ambitious text attempting and largely succeed ing to encyclopedically cover the theoretical fundamentals of incompressible nonturbulent Newtonian fluid mechanics. In addition, the book gives a flavor of the numerical methods by which fluid dynamics problems are often solved The ---------------C o nt i nu e d on page 75. 29

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(.3lillllijlllilili..._1e ___..:a_rn_in_:g=----------) TOWARD TECHNICAL UNDERSTANDING Part 3. Advanced Levels J.M HAILE Clemson University Clemson, SC 29634-0909 T he papers in this series* stalk the question of what we mean by an understanding of technical material. We have asserted that to understand has multiple mean ings, and we organized those meanings into a hierarchy of seven levels: (1) Making conversation; (2) Identifying ele ments; (3) Recognizing patterns; (4) Solving problems; (5) Posing problems; (6) Making connections; (7) Creating ex tensions. In the second paper of this series we discussed understanding at Levels 1 through 4 which we refer to as elementary understandings To progress beyond problem solving at Level 4, we must realize that solving a problem is not the same as knowing how to solve it. This realization marks the beginning of the transition to the more advanced levels addressed in this paper. The discussions here rely on the descriptions of brain structure and function that were s ummari zed in the first paper of the series Transition: Level 4 (Solving Problems) to Level 5 (Posing Problems) Motivation: Solving a problem is not the same as knowing how to solve the problem. Reformulation: The initial solution procedure is refined by rehearsal and the problem plus its solution are explored by exercising variations on a theme. LEVEL 5: POSING PROBLEMS We practice problem solving not to obtain an answer but to learn how to solve problems. That is, impiementing a procedure to obtain an answer occupies a lower level of Part 1, Brain Structur e and Function was published in the summer 1997 issue ofCEE (Vol. 31, No 3 ) and Part 2 El e m e tary L e v e ls ," appeared in th e fall 1997 i s su e (Vol. 31. No. 4 ) 30 understanding than does devising the procedure. To develop skills for so l ving problems we must confront new problems solve them, and then solve them again and again Repetition allows us to shift our attention from obtaining an answer to learning a procedure. Repetition also promotes creation of long-term memories, which we need for reusing a procedure in the future. The connections between repetition and memory will b e discussed first, then we will make connections be tween repetition and problem solving. Posing Problems to Create Memories Creating memories serves as one hedge against future needs. In particular, long-term memories (certain long-last ing neural networks and combinations of networks) enable us to reuse problem-solving strategies that we have found successful in the past. At the subconscious level, we don t know how the brain selects what ideas are to be remem bered That is in spite of popular wisdom, the brain does not lay down a memory for every menta l state nor for every sensory experience ; on the contrary most pass through short term memory and are lost. But we do know that we can conscio u sly select what ideas are to be remembered and we can consciously create those desired memories; the operative mechanism is repetition-repeatedly thinking abo ut the idea s Repetition causes the cortex to repeatedly fire the same pattern of neurons; s u c h repeated activations appear to strengthen synaptic junctions and perhaps develop new junc tions. Thus, by repeated u s e, a track through a wilderness becomes a path then a walk, and finally a highway. More over, besides strengthening connections repetition also seems to refine the neural network that reproduces the desired J.M Haile a professor of chemical engineering at Clemson University is the aut h or of Molecular S imu l ation, published by John Wiley & Sons in 1992. Co p y ri g ht ChE Diui s i on o f ASEE 199 8 Ch e mical Engin e erin g Education

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firing patters-it makes the network more efficient. When t h e mi n d contrives a pattern for a new idea, it seems to arise "on the tly"-the new thought is hastily thrown up as a permutation of an existing pattern. If a new idea seems interesting or important, and therefore worth remembering thereby creating long-term memories in the cortex .'2 1 If s u ch a scenario is true then all memories are formed by repeti tion; the difference between procedural and episodic memo ries i s merely that procedural memories are created by con sciou s repetition, while episodic memories are created bethen repeatedly thinking about it may create a new network that is largely separated from the parent network but connected to other networks t h at represent related ideas. ... we must realize that solving a problem is not the same as knowing how t o solve it. This low consciousness via repetitions instigated by the hippocampus. Posing Problems by Repetition Perhaps a helpfu l metap h or here would be scaffolding. A new, hastily constructed, net work is a fragile thing momentarily stabi lized by a scaffolding of neural connections that allow us to examine the new idea. If the idea is judged worthy, then we use repetition to strengthen important synaptic junctions in the network and remove the scaffolding. Of ten, t h e scaffo l ding is produced by studying t h e intermediate detai l s that appear in any realization marks We invest time and effort in learning so as to realize future benefits; this implies t h at we intend to remember what we learn. Prob lem posing is the level of understanding at which we use repetition for learning how to solve problems and for creating memories of the solution procedure. We identify two kinds of repetition : rehearsal, in which we repeat edly pose and solve the same problem, and variational, in which we pose and so l ve new problems that are closely related to the original problem. logical development, such as those that con nect a conclusion to a hypothesis, those that relate an effect to a cause and those that connect an answer to a problem statement. Without intermediate details, scaffolding is sparse or nonexistent and student under standing remain poorly developed. Rep etitions make such connections at first plausible, then acceptable, and finally ob vious-these correspond to stages in re the beginning of the transition to the more advanced levels addressed in this moving the scaffolding. paper. Rehearsal Having solved a problem, we rehearse the procedure to learn how we solved it. Since we know that the procedure leads to the solution, our minds during rehearsal are free to consider (1) why each step is impor tant and how it contributes to the sol u tion, (2) whether alternative steps may be more economical, and (3) whether the steps and intermediate results can be connected to o th er things we know, thereby attachi n g additio n a l Repetition also serves to distinguish pro cedural memories from episodic memories. Procedural memories are created by conscious practice, while episodic memories are apparently created from a single ex perience. How might episodic memories be formed? Deep in the brain, forming part of the limbic system, is the hippo campus-a pair of structures whose shapes each resemble that of a sea horse. If a hippocampus is damaged or removed, we lose the ability to form new long-term memories; old memories remain, but new ones do not form. Thus, the hippocampus plays some crucial role in forming long term memories. Further, it communicates with the cortex through two bundles of axons, one apparently for input and another for output. This suggests that the hippocam pus may act, in effect, as a buffer between short-term and long-term memories. [ JJ Perhaps when many networks in the cortex are busy attacking a hard problem-the cortex is too preoccupied to continue the structural changes that produce long-term memo ries. Perhaps, instead, networks in the hippocampus are acti vated loading the buffer. Later when networks become available in the cortex (perhaps during rest, or sleep), the h ippocampus "rep l ays" important patterns in the cortex, Winter 1998 meanings to the procedure, the solution, a n d the problem. Thus part of our activity during rehearsal is to probe a n d verify the logic of the algorithm; such activity conforms t o Poi ncare' s statement that in a chain of logic, the order of t h e elements is more important than the elements themselves.* Another part of rehearsal is the search for a better a l gorit h m. That is, problems are interesting and instructive to the ex t e n t that they can be solved in more than one way. P ro b lems can themselves be viewed as patterns with t h eir m u ltiple mea n ings reflected in the various ways by which they can b e solved. By repeated l y posing the same problem to o u rse l ves, we create opportunities for finding alternative sol u tion pro cedures and therefore for fi n ding additional meanings. A powerful motivation for rehearsal occurs when we i tend to present the solution to others-perhaps as a lecture or as a written document. Such presentations are most effec t ive when the chain of logic is economical, with every e l ement moving the development in an obvious way toward t h e goal. Such presentations are developed by rehearsing, w h erein we systematically try to reformulate a logical deve l op m ent i nt o See Level 3 in Paper 2, Chem. Eng. Ed., 31(4), 1997). 31

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a se quence that i s not only economical but also rich in meanin g Minsky 1 3 1 ha s emphasized that reformulation is the central act of creativity For example in spite of the common attitude that rehearsal is merely mechanical repetition the rehear sal involved in preparing lectures and writing text book s provide s opportunities for high level s of creativity a nd originality. 1 3 1 Variational Be si de s repeatedly po si n g the sa me prob l e m, we s hould also po se and so lve other problems that we create by systematically changing th e original problem. Thu s, we enhance problem-solving s kill s by po s ing variations on a theme. Thi s activity i s analogous to a practice technique u se d by mu s icians. Con s ider the pa ssage from Chopin 's third Pr e lude (Opus 28) for piano s hown in Figure 1 Thi s one mea s ure is sco red as a phra se-a mu sica l pattern of s ixteen notes. The third Pr e lud e i s marked vivace, which mean s a lively allegro, and corresponds to a speed of about a mea s ure per seco nd In fact a mea s ure per seco nd would be a little s low; five mea s ure s in four seco nd s would be mor e nearly correct. Thu s, each of the s ixteen note s s hould b e so unded at a uniform interval of about 5/100 of a second How i s s uch ski ll developed? Not s imply by repeatedl y playing the mea s ure as written, but rather by practicing rhythmic variations, s uch as are also shown in Figure l. Each variation shifts the emphasis to a different note hence a different finger ; additional variations would be u se d to s hift the emphasis among different gro up s of note s. Th e figure s how s only three variations, but in practice, the mu si cian routinely works through 40 or 50 variations of the sa me phra se And tho se are ju s t the rhythmi c variations; one al so works through varia tion s in tempo and in d y namic s ( loud ne ss). It may see m paradoxical th at to achieve what the composer ha s written, one practice s so mething other than what is written, but s uch practice prove s to be an effi cient way to attain a b so lut e control over the material; to e mb e d a metaphor within a met ap hor a chain i s mad e s tronger by sys tematically and r epeate dly s trengthenin g one link at a time. Likewi se, we can improve our gras p of and control over technical material b y posing variations on the theme inher ent in any problem Say the original problem require s us to obtain the vo lume V occupied b y one mole of nitrogen at P = 2 bar a nd T = 50 C. Havin g obtained the answer we can sys tematically vary that problem to create so mewhat differ ent, but related problem s to so lv e For example: ( 1) What would V be if T were 100 C in stea d of 50 C ? (2) What wou ld V be if P were 3 bar a t 50 C instead of 2 bar ? (3) What would V be if we had 5 mole s i nstead of one at 50 C 2 bar ? (4) Can we generalize what we've learned from the se four calc ulation s? ( 5 ) Wh a t if we knew N V T and needed to find P ? (6) What if we knew N, V, P and needed T ? ( 7 ) If the gas were a binary mixture of nitro ge n and oxygen what would change in all the se calculations? (8) What if the gas 32 Original 15= J,P r r rftru u [j 1 Var iation A Variation B Variation C > > > ti > > > 1 1 prutunu Figure 1. Thr ee rhythmic variations on the first measure of Chopin s Prelude for piano Opus 28, No 3. On each staff, h or iz onta l lin es and spaces between them represent keys on the keyboard; notes indi cate keys to be str u ck. On eac h of the four staffs, the same keys are to be struck; thus eac h staff co ntains the same pattern of not es. But the variations differ from th e original and fro m o n e another in that they require k eys t o be struck wit h diff e r e nt amounts of force and h e ld for different amounts of time. In an analogous manner, e n g in eering s tud ents can exercise th eir under stan din g of t ec hni ca l material by repeatedly using the same pattern of information but emp ha sizing different aspects of th e pattern ; that is they can pose and so l ve severa l varia tion s on a problem originally assigned by their instructor. were a twenty-component mi x ture ? (9) Pre s umably we ha ve u se d the ideal-ga s law in these calculations, so by what criteria do we de c id e th a t the ideal-ga s law no lon ge r a plie s? (10) When the id ea lgas law doe s n t apply, what s hould we use instead? Note that the original probl e m has led u s to devi se ten variations-effectively, ten new problems Thi s pro cess is most effective if students are merely s hown the s trategy and they create their own variations. Hopefully, the y eventually create problem s that the y don t know how to so l ve, then they initiate a dialo g w ith th e in str uctor. This proce ss is sys t e atic a nd can be applied to any problem ; in fact, rather than so lving 100 different problem s, st udent s see m to Chem i cal En gineering Education

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gain more by solving ten problems plus ten variations of each More on variational problem posing can be found in a book by Brown and Walter. 141 Earlier we noted that reformulation is a central aspect of creativity; this observation can now be pushed farther by noting that devising variations on a theme is itself a reformu lation. Hence, as Hofstadter has discussed 1 variations on a theme is the crux of creativity Any new object, process, or idea is created by modifying to a greater or lesser extent, existing objects, processes, and ideas. (There is after all, nothing new under the sun ) This aspect of creativity un doubtedly reflects the way minds work not by spontane ously creating a completely new neural net, but rather by continually modifying existing assemblies of neurons But the lesson here is that in practicing variational rep etition on solved problems students practice creating new things. And even though their first attempts are mundane and uninteresting, the habit, once acquired, can eventu ally serve them well. Transition: Level 5 (Posing Problems) to Level 6 (M ak ing Connections) Motivation : Having learned to solve a problem we should then ask whether that knowledge can be applied to other problems within the same domain and to analogous prob lems in other domains. Reformulation: Pattern, problem context, and solution are generalized to other domains. LEVEL 6: MAKING CONNECTIONS The understandings gained at Level 5 can require substan tial effort and labor because they often require us to make substantial modifications to dendritic trees and neural net works. So once such modifications are made, we try to increase their usefulness by connecting them to other net works that represent other patterns and problem contexts. That is, we try to project our newly acquired understandings into other domains of knowledge. Sometimes ideas for cross domain connections can be evoked by posing a simple heu ristic : Having solved the immediate problem can we now solve a similar problem or an analogous problem? But more often, we must employ cross-domain devices to help us find ideas that transcend domains Cross-domain devices are re lations, patterns or procedures that are invariant under changes of context; thus, they can be extracted from one context and inserted into another Such devices provide pow erful ways to increase understandings, and therefore it is pro b a bl y n ot surprisi n g t h at relatively few of them are known. We are always seeking to add new cross-domain devices to our repertoire, for every such device gives us another way to Winter 1998 learn. Five common cross-domain devices follow. (1) Our most powerful cross-domain device is mathemat ics. This s tatement often s urprises s tudents for they tend to view mathematics as a tool for computation But the real value of mathematics is that its rules for reasoning are inde pendent of context: mathematics is powerful because it is abstract. As a simple example, consider the exponential growth law where a may be positive or negative. This one equation applie s to certain proces s es in a number of very different and unrelated contexts. For example it describes the decay of radioactive isotopes the variation of density with altitude in a stagnant isothermal atmosphere, the growth of a popula tion in a limitless environment, the cooling of a warm body in cooler surroundings and the growth of capital in an inter est-bearing investment. (2) A second device for extending ideas across domains is provided by s c aling laws These devices exploit the extent to which certain behaviors are universal-independent of con text-when variables describing phenomena are scaled ap propriately. Thus we have the many dimensionless groups that correlate fluid flow and heat transfer in transport phe nomena, we have corresponding states ideas for correlating thermodynamic properties, and we have scaling laws for describing the behavior of materials near critical points. More generally we now have numerous disparate phe nomena referred to collectively as fractals, that are invariant under changes of scale. For example the Brownian motion first described by Robert Brown in 1828 originally referred to a microscopic scale ; when viewed through a microscope a minute particle displays random movements caused by collisions with molecules of the surrounding medium. But such movements are also observed on macroscopic scales in colloidal suspensions and on galactic scales in the motion of stars in open clusters such as the Pleiades (3) Another effective way to cro s s domains is by using an analog y : the presumption that if two things have certain similarities, then they also have other similarities. Analogies can be structural or functional and it is wise to keep clear which you intend in a particular case; the common pitfall is to assume that structural similarities imply functional simi larities. Examples of fruitful analogies include those among the linear transport laws of Newton, Fick, Fourier, and Ohm In thermodynamics, certain phase diagrams for vapor-liquid equilibria are structurally analogous to dia grams for liquid-solid equilibria. And in process control artificial neural networks bear certain functional analo gies to biological neural networks. ( 4 ) Still ano t her device is the metaphor which we use to describe an unfamiliar thing in terms of some more familiar thing. Unlike an analogy a metaphor typically attempts to 33

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relate two thin gs that have neither structural nor functional similarities. Minsky has emphasized that we typically use spatia l forms and concrete objects as metaphors for abstract ideas and concepts .r3 1 For example we talk about an idea being solid firm, fluid, or off-the-wall. More generally, we have family trees, the tree of life, the tree of knowledge dendritic trees, and logic trees; we have roots of a family, the root of an idea, the root of the matter, the root of a prob lem, and the root of all evil; we have bridges between domains of knowledge, the bridge of time, a bridge over troubled water, and a bridge (no less) to the 21st century One of the most compelling metaphors of recent years has been that of the desktop for manipulating operating systems on personal computers. (5) The last cross -d omain devices we mention here are various graphing templates for representing relations The most common is a simple x-y plot which shows how an effect is correlated with its cause. To have something less familiar, we show in Figure 2 examples of an interaction square ,r3 1 which shows how two causes either reinforce or compete in contributing to a single effect. In the first and third quadrants of the square the two causes act together to either amplify (quadrant I) or suppress (quadrant III) the effect. The interesting behavior occurs in the second and fourth quadrants, in which the two causes compete If we have a mathematical relation for how the two causes contrib ute to the effect then we can usually solve for the locus along which the two causes exactly compensate for one another. This locus transverses the second and fourth quad rants A particular example appears in the bottom of Figure 2, which shows how temperature and flow rate contribute to a particular value of the Reynolds number for fluid flow In the discussion of Level 3 (Paper 2 of this series) we observed that organizing knowledge into patterns provides a mechanism for improving the efficiency of education. Un derstanding at Level 6 provides a similar opportunity for efficiency At this level our intention is to find existing neural structures created in one context and apply them to problems in other contexts. When this can be done, we avoid much of the laborious effort required at Level 5 in making major structural changes to old networks Transition: Level 6 (Making Connections) to Level 7 (Creating Extensions) Motivation: Having learned to recognize and solve analo gous problems in various domains we should ask what problems can still not be solved, but which might be solved if we could extend, modify, or reformulate what we have learned. Reformulation: Generalizations are modified to attack other problems. 34 LEVEL 7: CREATING EXTENSIONS At Level 6, our understanding is sufficient for us to realize that a certain pattern, problem, or procedure, devised in one context, can be useful when transplanted in toto to another context. At Level 7 we realize that a complete transplant will not be useful but if the pattern, problem, or procedure is modified, then the transplant will bear fruit. In some situa tions, the necessary modification can be generated by merely devising a variation on a theme, but more likely, we need a reformulation that is more elaborate than a simple variation amplify r CauseB l suppress suppress -50 ? Effect Suppressed Re< 10 4 -25 Effect Amplified Cause A 0 T(oC) -To ? 2S amplify 50 Figure 2. (Top) Generic template for an interaction square that shows how two causes A and B contribute to one effect. (Bottom) A particular example showing how tem perature and flow rate combine to maintain the Reynolds number at 10 4 for water flowing through a 2.54c m pipe If the water temperature increases from the nominal c ondi tions of T 0 = 50 G at u 0 = 0 .7 2 f / s, pushing the operating point into the shaded region, then the desired Re can be regained by adjusting a supply value to decrease the flow Inversely, if the temperature decreases from T 0 Chemical Engineering Education

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That is we are seeking a homomorphjc projection across domains-a projection that identifies the essential features and that suppresses the inessential details An example is Maxwell's development of hjs theory for electromagnetic fields, which grew out of an analogy with vortices created in rotating incompressible fluids as de scribed by Helmholtz and Thomson Here i s Maxwell re viewing some of Thomson's papers on electrostatics and magnetism: l 61 . illustrations of magnetic force ... are not put forward as exp lanations of magnetic force ... They belong more properly to that remarkable extension of the sc ience of hydrokinetics .. (The first italics is Maxwell 's; the second is mine.) Creating extensions is a first step in the more general topic of pattern posing and as such it links the study of established patterns to the research involved in creating new patterns A principal strategy for posing new patterns is to shif t remove, or otherwise violate boundaries. By boundaries we mean the assumptions and preconceptions that are inherent in any established pattern concept, or procedure. Even experimen tal work involves assumptions; that is we design an experi mental protocol involving certain pieces of equipment under the preconceptions that certain phenomena will be observed and not others But bounds serve as barrier s that limit our thinking. So when a problem doe s not yield to attacks u s ing established patterns and procedures then we should test the bounds-examine our assumptions and preconceptions. As Root Bernstein has noted ,c7 1 in such sit uations it's not the problem that causes our lack of comprehension; rather the impasse arises from assumptions that we take for granted. Bounds are a product of negative thinking. Up to now this paper has focused on positive thinking-on identifying ways to promote firing of useful pattern s of neurons. But the brain has both inhjbitory and excitatory sy napses so not only can we learn productive ways to think but we can also learn to avoid unproductive ways to think. By imposing bounds on positive thinking, 1 31 negative thinking help s us be more ef fective because it helps us avoid wasting time on unproduc tive and counterproductive trains of thought. But we don t want the bounds produced by negative thinking to be too rigid because creative extensions can sometimes be found by shjfting those bounds or by recognizing that some bound s have been misinterpreted or are inappropriate. Achieving a balance between positive and negative learning require s a delicate hand on the part of the instructor for overem phasis on negative thinking can easily suppress creative impulses in students. Lastly, note that violating bounds-juxtapositioning the incongruous-is a principal attribute of intellectual humor. Indulgence in intellectual humor exercises the mind in vio lating bounds and produces combinations of thoughts that might otherwise remain unconnected. It is a conceit of mine Wint er 1998 that s uch exercise preserves so me flexibility in neural net works, and it might-ju s t might-represent some lowly prac tice at creating extensions. C ONCLUSIONS In thi s series of papers we have presented a strategy for s tudying technical material ; the strategy is organized into a hjerarchy of seve n level s We enter the hierarchy at Level 1 when our attention is drawn to a topic and we begin to pose questions about it. We leave the hierarchy as it applies to a particular topic at Level 7 when we begin to consider how the topic 's objects and concepts can be modified so that they can be applied to other topics. Note that problem so lving at Level 4, occupies the central level in the hierarchy but problem so lving is neither the goal nor terminal point of the hierarchy An overriding theme of these papers ha s been that any thing interesting or useful has multiple meanings and under s tandings of tho se meaning s arise out of connections: con nections among objects and concepts to form meaningful patterns, connections between patterns and a problem con text, connections among different problems and their con texts, and connections among different domains of knowl edge. The hierarchy of understanding provides a scheme for sys tematically making connections. The hierarchy can be u se d by instructors to help organize how material is pre se nted to s tudents and to help assess st udent under s tanding. Similarly, it can be u se d by students to help organize their s tudy of a topic, to assess their comprehension, and to iden tify what should be done to move to the next level. We have devoted considerable effort in trying to find meanings for the word understanding. Perhaps some addi tional insight can be gained by inverting the issue and identi fying thjng s that are not under s tanding: 1) Verbal fluency is not understanding-people can en gage in conversations about a topic without being able to answer questions about the topic or to explain the topic to others; 2) Experience is not understanding-people routinely use automobiles and computers without understanding how s uch things work; 3) Solving a problem is not understanding-people can so lve a problem without realizing how they solved it and without being able to explain their procedure; 4) Making predictions is not understanding-before 500 B.C. the ancient Babylonjans had correlated sufficient observations so that they could predict lunar eclipses ,csi but they could not explain the geometry that causes an eclipse/ 91 5) Accumulated knowledge is not understanding-the Nobel laureate Albert Szent-Gyi:irgyi once re marked -------------Continued on page 39. 35

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t.a_5_3._c_l_a s_s ~ o_o_m __ ____ __,) HELPFUL HINTS FOR EFFECTIVE TEACHING R OBERT H. D AVIS University of Colorado Bould er, CO 80309-0424 A few years ago, when I was new as Chair of Chemi ca l Engineering at the University of Colorado, my co lle ag ue s and I felt the need to take actio n to improve our tea c hin g. The idea was born, in part, out of a se n se of frustration in trying to comm unic ate effectively with s tudent s in the face of increased enrollme nt s in our co u r ses a t the time. As a starting point we h e ld a brainstorming workshop attended by ( nearly ) all faculty. We next formed s mall gro up s, each with the sa me ta sk of makin g a list of effective teachin g attributes. Each group then presented its findings which were di sc u sse d and organized into fo ur categories: Course Organization and Preparation Classroom Communication R apport with Students Assignments, Examination and Grading In preparation for our workshop, I prepared a handout of hint s for effective teaching that I later revised with the in sig h t s gained from the workshop. Since it is easy to lo se foc u s of our primary respo n sibility as educators a n d to fail to se t aside ample time for helping our s tudent s learn I mak e it a habit to review the se hint s severa l times a year I h ave also give n thi s handout to our all of our fac ult y. What follows is the most recent ve r s ion of the handout with annotations in italics added for this article. The reader s hould understand that it i s not a systematic or complete Robert H Davis is the Patten Professor and Chair of Chemical Engineering at t h e Univer sity of Colorado. He received a BS degree from the Universi t y of Ca l ifornia at D avis and his MS and PhD degrees from Sta n ford Uni versity. H is research and teaching i n terests are in fl u id mechanics membrane separations and biotechnology sc ho l arly work on teaching, but rather one that has evo l ved from my experie nc es a nd those of my colleagues In this se n se, it h as a similar flavor to several other recent articles r 1 3 l on personal perspectives and many of the conclu sio n s are ones of common se n se an d experie nc e. I e n co ura ge the reader t o also cons ult more thorough s tudie s and discus sio ns of teaching m et hod s and l ear nin g s ty l es 14 6 1 I COURSE PREPARATION AND ORGANIZATION I [;ii Ask to teach courses r e l ated to your expertise Your knowledge of the material and your enthusiasm both ingredients of effective teaching / 7 1 will be highest in such courses. [;ii Outline the entire course in advance. A logical presen tation of the material will be most effective if you decide up front what the course learning goa ls are, what topics are to be covered, and how much time should be spent on eac h topic, and then prepare a detailed ( two to four pages) numbered outline that is used throughout the cou r se. [;ii Prepare well-organized n otes for each class period lt is easy to get into ( and hard to get out of) the pattern of preparing for a class the night before ( or even the same day). While this approach works for some of my co ll eag u es, I am more relaxed if I prepare a week or more in advance [;ii Set asi de at least thirty minutes right before each class period to revi ew the mat e rial s and to focus your t h oughts. [;ii Read and assimilate severa l so urce s in addition to th e assigned text. Your cou r se should hav e your personal touch and should be prepared in a sty l e and sequence that makes sense to yo u rather than just following a text. I recommend that you go through several books journals, popular press and notes from other faculty to Cop y r i ght ChE D iu ision o f ASEE 1998 36 Chemical Engineering Education

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In preparation for our workshop, I prepared a handout of hints for effective teaching that I later revised with the insights gained from the workshop. . I make it a habit to review these hints several times a year. select your materials. 1:.iii1 On the first day of class, give the students a course sy llabu s that includes the course goals, an outline, reading assig nment s, h omework expectations, exam sc hedul e, and grading policies. 1:.iii1 On the first day of class, and periodically throughout the term, discuss the relevance of the course material to practical app li catio n s and to the rest of the curriculum. If we want students to learn, then we must provide moti va tion on why the material is important F 1 Even better ask them to brainstorm on real-lif e applications and tie-ins with other courses, either in small groups or in an open-class discussion l:.iiil Provide and di sc u ss review sheets prior to each exam These help the students see the big picture of what they (should) have l earned and how it ties together. l:.iiil Your course o utlin e, note s, and material s s hould be reviewed and updated each time you teach the course I CLASSROOM COMMUN/CATION I l:.iiil Put an outline on the board and provide a preview at the beginning of each class period whether giving a lecture or u si n g anot h er s t y l e; u se a brief review of the pr evi ous class period as a transition l:.iiil Summarize the key points, with the help of st ud ents, at the end of each class period. l:.iiil Com e to c l ass well pr epared a nd undi stracted, so that yo u are l ess lik e l y to stumb l e over derivations or so luti o n s. I f you do make a mistake, admit you r error. I f you get stuck promise the students that you will find the answer for next time; do not bluff. fl/ l:.iiil D o n ot read your notes to the s tudents. Simply reading l ecture notes or from a book i s a sure way of turning off the students learning processes J 81 While some gifted faculty can deliver an entertaining and factual lecture with no written material s, I am most comfo rtable with a middle-of the road approach where I bring about five pages of handwritten not es to a 50 minute class period-about half of them represent material that I put on the board for the students and the rest is highlighted prompts to me on questions, illustrations stories, etc l:.iiil Write n eat ly on the bo ard or over h eads, u se vis ual s, a nd give s tudent s s ufficient time to take not es. B oard use Winter 1998 should follow an orderly and logical progression, the physical layout of which should be v isuali zed in advance and include numbered headings co nsistent with the cou rse and class outlines. Visuals (pictures, drawings, graphs, charts, etc ) are excellen t l earn in g tools J 71 When using overheads, it is especia lly impor tant to give students time to write down what is ieces sary-or to provide them w ith copies of the overheads. I like a mix of writing on the board for the main part of the le ct ure interspersed with br eaks where I pass out a one-page handout of an example or derivation that I then go through quickly using an overhead. 1:.iii1 Ask questions in order to maintain the st udent s' foc u s and assess their und erstand in g of the material. Well formulated questions should stimulate the students' thought processes _f 101 Give the students plenty of t im e to answer the questions, and provide prompts or hints, if necessary. I sometimes call on students by name; this must be don e w ith co urtesy and respect, as some st ud ents prefer to remain in the background A student must never be embarrassed or ridiculed for not knowing the answer. l:.iiil Use examples in class that s tudent s can relate to In a heat-transfer course, discuss why the same temperature "fee ls different" in dry air humid air, water, and wind. In a fluids course, c alculate how much the shower temperature will go up when the toilet is flushed, and suggest an alternative plumbing design that minimi zes this effect. l:.iiil Start and end the class period o n time a nd gent l y but firmly maintain order. I RAPPORT WITH STUDENTS l:.iiil Learn eac h s tudent 's name. While this is more difficult with larger classes suggestions include asking each student to write a short biographical sketch on the first day of class, taking photographs, handing back homework individually just before the start of class, greeting students by name, and asking students their names when y ou don t know them. l:.iiil Sc h edule at least two office hours or optio n a lhe lp sessio n s per week at time s availab l e to the st ud e nt s. On e should be the day before an examination is held or homework is due and the other(s) earlier in the cycle. 37

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Most important, be present for yo ur office hours and inform the students and reschedule those times for which there are unavoidable conflicts. [:.iii Be willing to see students outside scheduled office hours and help sessions. One of the most difficult issues we face is how to make availability to students a high priority when there are so many other demands on faculty time. When students drop by, my intention (though I often fall short) is to set other things aside and listen and help. If meeting their needs will take longer than I can spend at that time, then I set up an appointment To make the necessary uninterrupted time for writing and other tasks, I come in early; others may prefer to stay late or spend part of the day working at home. [:.iii Be attentive and sympathetic to students; do not say anything that might make a student feel put down, either in public or in private The most common student complaints that I receive as Department Chair is that they have not been treated with respect by faculty. While insensitive words or actions are often unin tended, we must never lose sight of our calling to serve and encourage our students. [:.iii Take at least one class period, or parts of two or more to dispense with the course material and discuss a subject such as professional ethics or your own experi ences 1:.iii1 Solicit and respond to mid-course feedback by a group interview or evaluation questionnaire. Using class representatives or peer evaluation can also yield useful feedback while there is still time to make changesY 111 [:.iii Provide food At help sessions during special occa sions in class or for an end-of-term party. [:.iii Understand that relationships with students do not end with the course. If you show students that you care, then they will naturally ask you to write recommendations and provide career adviceJ 21 Some will come to you with personal problems (know when to seek help from campus professionals). Some will stay in touch for ye ars These are some of the responsibilities and rewards of our profession. ASSIGNMENTS EXAM/NA T/ONS AND GRADING [:.iii Inform the students of the course grading scale or method at the start of the course The second most common complaint that I receive from students involves grades-that they were not informed by the instructor that a certain exam would make up half of their grade, that they were not told what performance was required to get a "B" in the course, or that a friend received a 38 higher grade with the same or lower scores. [:.iii Make sure that the exam problems correspond to the course objectives and learning goals, which should be the major topics of the class periods and homework assignments. Students learn more when they are actively involved, 171 and one of the best activities is homework on carefully selected problems [:.iii In each assignment and examination, include a mjx of simple, medium, and difficult problems. Since students learn and demonstrate knowledge in different ways, it helps to include a variety of exercises.m [:.iii Develop solutions for all homework and exam ques tions before they are handed out, and work the prob lems yourself. Not only does this serve as a check that the probl e ms are reasonable but it also gives you the necessary preparation for answering questions. [:.iii Grade as thoroughly as time allows, providing com ments and partial credit. Careful grading is needed for fairness and consistency, and it provides important feedback to the students. This requires time; if neces sary, use this article to help convince your department to invest adequate resour ces in graduate and under graduate cou rse assistants. [:.iii Return graded homework exams, and reports promptly. Students wantfeedback J7 1 More important prompt grading shows students that they are a high priority. These hints for effective teaching can be summarized in one word: time. It takes time to prepare a course well; it takes time to know students. If we care deeply about stu dents and their learning then teaching will be a high priority among our other responsibilities and we will take the time to do it well. REFERENCE S 1. Bird, R.B ., "Seve n Rules for Teaching," Chem. Eng Ed. 27 (3), 164 ( 1993 ) 2. Turian R.M. "The Quest for Excellence in Teaching ," Chem. Eng. Ed ., 27(4 ), 182 (1993) 3. Bowman, C.N., "Teaching in the First Few Years," Chem. Eng Ed. 28(4 ), 280 (1994) 4. Wankat, P.C. and F.S. Oreovicz, Teaching Engineering, McGraw-Hill, New York, NY ( 1993 ) 5. McKeachie W.J. Teaching Tips: A Guid e book for the Begin ning College Teacher, 8th ed., D .C. Heath & Co., Lexington, KY ( 1986 ) 6. Kolb, D A., Learning Style Inventory, McBer and Co., Bos ton MA ( 1985 ) 7 Wankat, P.C ., "What Works: A Quick Guide to Learning Principles ," Chem. Eng. Ed., 27(2) 120 ( 1994 ) 8. Wankat P .C., "Synergism Between Research and Teaching in Separations, Chem Eng. Ed ., 30(4 ) 202 ( 1997 ) 9. Felder R.M. "Things I Wish They Had Told Me ," Chem. Eng. Ed ., 27 (2), 108 ( 1994 ) 10 Felder, R.M ., "Any Questions? Chem. Eng. Ed 27(3 ), 174 ( 1994 ) 11 Brent, R., and R.M Felder It Takes One to Know One ," Chem. Eng. Ed ., 30(1), 32 ( 1997) 0 Chemical Engineering Education

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To w ard T e chnical Un d erst anding Continued from page 35. that during his study of muscular action he came to rea l ize that t h e more h e learned, the less he u n derstood, and so he became fearful of finally learning everything, but understanding nothing. 1101 The discussions here raise many questions that would seem to serve as starting points for further, more detailed investigations Here is a list of some of the more obvious ones. 1. If the pattern can indeed serve as the fundamenta l unit of understanding then what are those patterns that distinguish one topic from another? For example, what patterns distin g u ish transport from thermodynamics and thermodynamics from reaction kinetics? Then, by extension, what patterns distinguish chemical engineering from chemistry and from ot h er engineering disciplines ? 2. Repetition i s necessary to so lidif y certain kinds of under standings, and therefore some amount of redundancy need s to be incorporated into a curriculum. But efficiency in edu cation can be attained by appealing to pattern s and other devices that cross subject domains. To what extent can a curricu l um be made more effective by organizing it around patterns rather than topics ? 3. What are appropriate cues th a t will activate, in student brain s, proper pattern s and homomorphic projection s needed to address particular problem s ituation s? Are there mini mum numbers of cues that are s ufficient ? 4. Can we contrive a complete li st of de vices for making connections across subject domains ? I s there a minimum number of such devices that a s tudent should be able to use? What are the most effective ways for s tudent s to develop facility with cross-domain devices ? 5. Can we devise systematic procedure s for identifying and testing default assumptions and probing tacitly assumed boundaries? 6. Are there ways to gauge the importance and impact of negative thinking relative to po s itiv e thinking? 7. What i n dicators can we devi se for determining when s tu dent s successfully make a transition from one level of un derstanding to another? 8. Presumably we do not expect all students to achieve the same levels of understanding What levels are appropriate for BS students? For MS students? For PhD students? 9. Traditional description s of brain function use time to iden tify two kinds of memories : short-term (you look up a phone number and remember it only long enough to dial it) and long-term (you still remember your name). But recent evidence suggests a third: intermediate-term memory in w h ich a buffer (perhaps the hippocampu s) is loaded while structural changes are made in the brain to lay down the corresponding long-term memory. Thu s, students who cram before a test often do not retain the crammed information because they are only loading a buffer, not creating longWinter 1998 term memories. Thi s s ugge s t s that si mple linear progres s ion thro u gh material over a semester may not be as effec tive as so me cyclic procedure in which important patterns are revisited at inter va l s. Revisiting amounts to repetition, which stimulates creation and so l idification of l o n g-term memories and pares away superfluous scaffolding. If this conjecture were confirmed, what kinds of cyclic presenta tions should be used ? What are the optimum times between re-exposure to the sa me patterns? JO. Finally, note that throughout these papers we have empha s ized what rather th a n how. So how do we he l p students progress through a hierarchy of under s tanding ? Understanding never ends. Minskyl 3 l ACKNOWLEDGMENTS Many of the ideas presented in this series were tested and clarified by continually referring to Marvin Minsky's book 1 The Society of Mind ; without that book these papers would have taken a very different form. Over the years of my struggle to understand understanding I have learned much from discussions with my colleagues R.W. Rice (Clemson) and J.P. O Connell (Virginia); my thanks for their forbearance. REFERENCES 1. Rolls E.T ., and A. Treves "Neural Networks in the Brain Involved in Memory and Recall ," Progress in Brain R es., 102 ,335( 1994 ) 2. Calvin, W.H ., Th e Ce r ebral Code, MIT Press Cambridge, MA ( 1996 ) 3. Minsky, M., Th e Society of Mind, Simon and Schuster, New York, NY ( 1986 ) 4 Brown S.I ., and M I. Walter, The Art of Problem Posing Erlbaum Hillsdale, NJ ( 1983 ) 5. Hofstadter D R ., "Variations of a Theme as the Crux of Creativity," in Metamagical Th emas, Basic Books, Inc ., New York, NY ( 1985 ) 6. Maxwell, J C., Review of Reprint of Papers on Electrostat ics and Magnetism by Sir W Thomson," in The Scientific Pap e rs of Jam es Clerk Ma xwell, Vol 2., W.D Niven ed., Cambridge University Press, Cambridge ( 1890 ); reprinted by Dover Publications New York NY, p 301(1965) 7 Root-Bernstein, R.S., Discovering Harvard University Press, Cambridge, MA, p. 296 ( 1989 ) 8 Neugebauer, 0., Th e Exact Sciences in Antiquity, reprint of 2nd ed., Harper & Brothers, New York, NY ( 1962); 1st ed., Princeton University Press ( 1952 ); 2nd ed., Brown Univer sity Press ( 1957 ) 9. Toulmin, S Foresight and Understanding, Indiana Univer sity Press, Bloomington IN ( 1961 ); cited in D A. Crosby and R.G Williams, "C reative Problem-Solving in Physics Phi losophy and Painting: Three Case Studies," in Creativity and the Imagination, M. Amsler, ed., University of Dela ware Press, Newark DE ( 1987 ) 10 Szent-Gyorgyi, A. In Search of Simplicity and Generaliza tions (5 0 Years Poaching in Science )," in Current Aspects of Biochemical Energetics, N O. Kaplan and E.P. Kennedy, eds., Academic Press, New York, NY ( 1966 ) 0 39

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,a~5,~_,r:,a=-b=o ~r.=a:to=r=y~----------.) EXPERIMENTS ILLUSTRATING PHASE PARTITIONING AND TRANSPORT OF ENVIRONMENTAL CONTAMINANTS SUSAN E. POWERS, STEFAN J. GRIMBERG Clarkson University Potsdam, NY 13699-5710 H istorically, chemical engineers have been primarily concerned with maximizing the efficiency of indi vidual processes while designing chemical produc tion facilities. Current regulatory pressures to minimjze risks associated with the production of chemicals, however, re quire chemical engineers to understand the fate of these chemica l s in the environment. The fundamental mass trans fer processes controlling the migration of contaminants in environmental systems are similar to those in chemical engi neering processes. There are distinct differences, though, that have implications in how individual processes are ana lyzed. For example contaminant concentration in the envi ronment is generally very low (on the order of parts per million (ppm)), and the number of compounds present in a given environmental system is very large and unknown com pared with typically well-controlled chemical engineering processes. The comp l exity of these systems needs to be simplified in order to describe mass transfer process enviSusan E. Powers received her BS and MS degrees in chemical engineering and environ mental engineering respectively from Clarkson University In 1992 following the completion of her PhD in environmental engineering from the University of Michigan she returned to Clarkson where she is presently Assistant Professor in the Department of Civil and Environmental En gineering. Stefan J. Grimberg received a Dip/om Engi neering (TU) degree in chemical engineering from the Munich Technical University and his MS and PhD degrees in environmental engi neering from the University of North Carolina Chapel Hill He presently holds the position of Assistant Professor in Clarkson s Department of Civil and Environmental Engineering ronmental systems. At Clarkson University, the fate of hazardous organjc pollutants in the environment i s covered in the class "Haz ardous Waste Management Engineering Senjor-level stu dents from the departments of civil and environmental engi neering, chemical engineering, and industrial hygiene typi cally enro ll in this class. Fundamental processes governing the environmental fate and transport of organic contami nants are covered during introductory lectures and are used throughout the semester to s upport more advanced material related to human exposure levels, risk assessment, and de sign of treatment strategies. Throughout the semester the relationships between chemical behavior and molecular struc ture (i.e., size and polarity) are emphasized. After thjs class was taught for two years, it became appar ent that students had difficulty grasping the concepts of partitioning of so lute s between phases. Thus, the experi ments described here were developed to help students under stand the partitioning and transport of organic compounds in environmental systems. Constraints of class length (50 min utes), size (30-40 students per section), and budget, how ever limited the scope of possible experiments. A creative solution of using nontoxic colored solutes allowing strik ingly visual detection as the solutes partitioned between phases, effectively illustrated the concepts of phase par titioning and enabled all students to be active partici pants in both the qualitative and quantitative components of this laboratory. BACKGROUND AND THEORY A significant fraction of groundwater contamination in the United States is the result of spills and disposal of organic liquid s in the ground. The organic phases, referred to as nonCo p y ri g ht ChE Di u i s i on of ASEE 1 9 9 8 40 Ch e mical Engineering Education

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aqueo u s phase liquids (NAPLs), are typically consid ered to be "immiscible" with water, although their solubilities are high enough to contaminate groundwa ter at levels higher than drinking-water quality stan dards.Lil Figure I illustrates the partitioning and trans port processes affecting a NAPL such as gasoline. Since gasoline is less dense than water it accumu lates at the water table Subsequent partitioning of contami n a nt s into both the groundwater and soil gases wi ll occur. Fundamental processes governing the environmen tal fate and transport of organic contaminants are covered during introductory lectures and are used throughout the semester to support more advanced material related to human exposure levels, risk assessment and design of treatment strategies. re-".__-~ leaking underground storage tank volatilization I dissolution convection and dispersion The eq uilibrium dissolution of solute from a NAPL and subsequent sorption of the aqueous-phase solute to sand are considered in this laboratory. Because of the low concentrations in vo l ved in these processes it is assumed that the density and molecular weig ht of the phases, a nd activity coefficie n ts of eac h species in the aqueous phase, remain essentia ll y consta nt. For m a n y NAPLs, it is reasonable to a l so assume that the organic phase is a n ideal so luti o n and, thus that activ ity coefficients in this phase are close to one. With these simp lifi cat i o n s, phase equi libri a governing the partitioning of solutes between these environmental compartments is often approximated with linear rela tionships describing the concentrations of a species between phasesr 2 1 pool of gasoline 1 dispersion l plume of contaminated groundwater Figure 1. Pro c ess e s affecting th e fate of a NAPL such as gasoline in the subsurface. NAPL-water systems: c = c x Soil-water systems : q = K d C where (I) (2) C concentration (mg/L) of a compound in the aqueous phase c so lubilit y of the pure liquid chemical in water ( mg/L ) X mole fraction of this compound in the NAPL q concentration sorbed on the soil (mg/kg ) K d soil-water distribution coefficient ( L/kg ) Equation (1) is R aou lt 's Law for liquid liquid equilibria and ha s been s hown to be fairly accurate for even com plex NAPL mixtures comprised of chemicals with low sol ubiliti es lll Both c a nd Kd are partition coefficients describing the linear eq uilibrium relationship between phase conce ntr at i ons. Their va lu es are hi g hl y dependent o n the molecular structure of the compound .r3 1 Nonpolar orga ni cs are hydrophobic, ex hibitin g trends of generally decreasing so lubiliti es and in creas in g soi l -water distribution coefficients with increasing molecular we i g ht. The presence of polar functional gro up s, especia ll y those with 0, N, or S atoms, decreases the aque ous-phase activity coefficient thereby greatly increasing the aqueo u s -ph ase so lubilit y and decreasing the soi l -water dis tribution coefficie nt of organic compou nd s Following th e partitioning of organic compounds from the NAPL to the aq u eous phase the co nt aminant molecules are transported w ith flowing groundwater, potentially polluting Winter 1998 downgradient sources of drinking water. Convection (also called advection by environmental engineers) a nd dispersion are the predominant transport mechanisms, althoug h the sorp tion of solutes to soil effectively retards the transport rate Assuming equilibrium between solid and the liquid phases, the standard transport equation with a linear sorption term added can be written in one dimension as (3a) or {3b) where D 1 hydrodynamic dispersion coefficient in the l ong itudin a l direction u x average lin ear interstitial velocity of the aqueous phase R retardation coefficient (R = 1 +pbKd In) n porosity of the porous medium P b bulk density of the porous medium The retardation coeffic i ent can also be described as the ratio of the mean velocity of water ( u x) to the mean ve l ocity of the so lut e (u x ) so l (4) 41

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A solute with a low retardation coefficient (R~ 1) will be relatively mobile within an aquifer system, potentially resulting in higher human exposure levels than a solute that sorbs strongly. EXPERIMENTAL DESIGN AND RESULTS A laboratory experiment was developed to reinforce the concepts of phase partitioning and its relationship to mo lecular structure and the mobility of a solute in a groundwa ter system. Three NAPLs with different colors and hydro phobicities were mixed with water, and then the contami nated water infiltrated through sand to observe the parti tioning of the colored solutes. This experiment was in cluded in the hazardous waste management class during the fall semester of 1995 An assessment of the effectiveness of this laboratory indi cated that the students perceived an increase in their compre hension of these concepts. Results of their homework as signments, however, showed that they still strugg led with quantitative homework problems. Thus an additional ex periment was designed for the 1996 class that involved a more quantitative measure of retardation coefficients as con taminated water samples were pumped through a soil col umn and the velocity of the contaminant was measured relative to the velocity of water. Materials Adding dye to nontoxic organic phases created three NAPLs with different colors and a range of partitioning behaviors. Table 1 describes the composition of the red ," blue ," and "green" NAPLs. The polarity (or hydrophobicity) of these dyes is the property critical to their partitioning behavior and the success of the experiment. The overall polarity of a molecule depends on contributions of polar atoms (0, S N Cl) and nonpolar atoms (C, H). Quali tatively oil-red-o is more hydrophobic than methylene blue because a greater fraction of the oil-red-o molecule is com prised of carbon (see Table 1) Similarly green food color is more polar than methylene blue since the number of polar atoms in green food color is higher than in methylene blue (Table 1). In order for the observed partitioning of the color to be representative of the overall bulk NAPL partitioning, the polarity of the dye ha s to mimic the polarity of the NAPL. The polarity of the bulk organic liquid s used in creased from mineral oil to ethanol. Thus the polarity of the selected colors represent the polarity of the NAPL. Other materials included tap water as the aqueous phase and clean quartz sand, suitable for a child's sandbox, for the soil. r Laboratory I A Qualitative Understanding of the Partitioning of Solutes Between NAPL-Water and Water-Sand Systems The first laboratory allows a qualitative assessment of the Figure 2. Photograph illustrating the partitioning of red, blue, and green solutes (left to right) from a NAPL to water. TABLE 1 Composition of Colored NAPLs 42 NAPL Bulk Or~a11ic Phase Solutt! 1 1 red mineral oil oil-red-0 1 21 blue 5 % ( by vo l. ) octanol in mineral oil methylene blue 131 green ethanol green food color 141 1 Only a sma ll amount of dye required for each to provide vivid color 2 Available through Fisher Scientific ( biotechnology reagent) 3 Dis so lved in octanol prior to mixing with mineral oil Chemical Formula Characteristics c 6 H 24 N 4 0 ve r y h ydro phobi c C 1 6 H 1 8 N sc1 slightly hydrophobic C 16 H 10 0 7 Cl 2 Na 2 S 2 151 hydrophili c c, 6 H s O s N NlS 1 61 4 Mixture of FD&C Yellow 5 and FD&C Blue 1; available through McCormick & Co Inc ., Maryland 5 FD&C Yellow 5 (5) 6 FD&C Blue 1 (5) Chemical Engineering Education

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partitionin g behavior of the red, blu e, a nd gree n so lut es as well as the bulk organic pha ses T ea m s of 3-4 s tudent s eac h were provided with bottle s containing eac h of the thr ee NAPL s, three 40-mL sc r ew -cap v i a l s a bout 75 % full of water, two filtering crucibles about 50 % full of dry s and t wo 50-mL beak e r s, and seve ral di s po sa ble ca pillar y pipette s. In the first pha se of the experiment st ud e nt s observed th e range of po ss ible partitionin g b e h av ior s b etwee n the NAPL s and aqueous pha se The s tep s s impl y involved adding apTABLE2 Questions Posed to Increase Co nceptual U nderstanding Questions for NAPl..,.water partitioning C l ass i fy the so lubilit y (so lubl e, partia ll y so lubl e in so lubl e) of thr ee colo r ed so lut es and the bulk organic pha ses Di sc u ss th e imp li cations of the se differences on the fate of NAPLs in the subsurface What difference s in th e chemica l st ru ct ur es would yo u expect based on th e obse r ved so lub ilities ? Questions for aqueous phase-soil partitioning R ank the so lut es in o rd er of increasing potential for sorption; exp l a in your answer Di sc u ss the implications of the se differences on the mobility of the se so lut es in th e environment Wh at diff ere n ces in the c h emica l structures wo uld yo u expect b ased o n th e o b served so rp t i o n beha v ior ? S ummar y questions Are the observatio n s and co n c lu s i o n s drawn from the so lubili ty experime nt co n s i ste nt w ith the re s ult s of the so rpti on experiment? Exp l ain. D escr ib e th e overal l fate of eac h of the three NAPLs fo ll ow in g a spi ll t o th e environment plexiglas columns with rubber stoppers syringe pump with 100-ml syringes beaker for effluent tygon tubing Figure 3. S c hemati c of experimental system for column r e tardation exper im e nt. Wint e r 1998 proximately 1 mL of NAPL to each of th e three water v ial s, ge ntl y s hakin g th em to eq uilibrat e, a nd then observing the di stri bution of color a nd the bulk organic fluid between pha ses. Re s ult s range from no observable partitioning of the h y drophobi c red so lute in mineral oil to the complete di sso lution of the ve r y polar gree n so lut e in et hanol (see Figure 2). Th e blue so lut e illustrates th e co ncept of having a partially so lubl e so lut e in a n esse ntiall y in so lubl e bulk orga ni c phase In this case, much of the blue co l o r trans ferre d to the a qu eo u s phase, a lth o u g h most of th e vo lum e of NAPL re main e d as a separate immi sci ble pha se. This case is most representative of e n v ironm e ntall y sig nifi ca nt NAPLs s uch as gasoline. Th e seco nd phase of the first laboratory provided a greater under s tanding of the partitionin g of so lute s betwe e n aque o u s and soi l pha ses. As d esc ribed a bo ve, the m ix in g of NAPLs and water ge n erated blu e and g reen co ntaminated water. Each of the se aqueous ph ases was then poured through san d in the filtering crucibles th at were held over 50-mL beaker s. The very polar green so lut e was not retarded as ev idenced b y the lack of c h a nge in co lor of either th e sa nd or water. With the le ss polar blu e so lute howe ve r th e sa nd turned blu e and the effl uent became clear illu s tr at in g that s li g htl y so luble so lute s can b e stro n g l y sor bed greatly d creasing contaminant co n ce ntration s in the aqueous pha se In order to h e lp st udent s in crease their under s tanding of partitioning behavior we po sed severa l question s to pro mot e their a bility to connect experimental observations to fundamental co n ce pt s (see Table 2) These que s tion s fo c u se d primarily on the rel a tion s hip b etween chemical s truc ture a nd mobility of chemicals in the e n viro nment. r Laboratory 2 A Quantitative Measure of Solute Retardation The seco nd laborator y was developed to quantif y the ex tent of so lute so rption Th e equipment required for thi s labo ra tory (see Figure 3) was mor e extensive and, thu s, the l a borator y was co nducted as a demon s tration with s tudent s taking turn s makin g th e measurements over tim e Colored aq ue ous pha ses for thi s ex p eri m e nt were pr e par ed b y the direct addition of dyes into the aqueous pha se (0. 05 g/L methylene blue for the blue aqueous phase and 10 mL/L g reen food color for the "g reen a queous phase). Two Plexigla s columns (3.8-c m di a meter by 25-cm long ) we re care full y pack e d with a uniform san d (3 0-40 me s h ; d 50 = 0.5 mm) to pro vi d e a relatively h omoge neou s sa nd to help minimize so lute di spersio n within the column. Several pore vo lum es of de gasse d water were th e n pumped throu g h each column to displace and di sso lve all of the air. At t=0 pump ing of the blue and green aqueous phases through the co l 43

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umns at rates typical of groundwater flow ( Q=0. l rnL/min) was initiat ed. Using colored so lute s allowed vis u a l assessment of the migration of these so lute s Th e interface between clean and co lored water was marked on each column over time and the average di s t a n ce traveled by the co lored water was recorded. Assuming that convection i s the predominant tran s port mechanism, the position of the s h arp front mark ed by the co lored water was u se d to estimate the inter s titi a l so lute ve locit y Thus, the retardation coefficient (E q. 4) was calcu lated as where R = QI An Lit Q vo lum etric flow rate of water A co lumn cross-sec tional area L distance traveled by the co l ore d water in tim e t n porosity included to convert to an int ers titial aqueous ph ase velocity {5) Equation ( 5) can be rearranged to calculate the retardation coefficient by linear regression of th e L-versu st data Figure 4 illu s trates difference s in the travel time of the s olutes through the soil columns. As expected from the qualitative experiment described above, the greater di s tance traveled by the very-polar green so lute indicates that it i s much more mobile than the les s -polar blue solute. The ob served variability in the po s ition of the front around the column perimeter at any point in time (F igure 4) i s attributed to column-scale heterogeneities in soi l permeability that af fect local rates of convection To accommodate for thi s variability, the experimental analysis was completed u s ing the average of four measured travel distances at each time. These average travel distances with error bars representing one standard deviation are included in Figure 5 Linear regre ss ion of the data was used to estimate the retardation coefficients for each so lute. Regression coeffi cients greater than 0 99 were obtained in both cases. The low retardation of the green solute (R= 1.4.1) confirms the fact that this solute would be highly mobile in an aquifer system, while the higher retardation coefficient for the blue so lute (R=4.4.2) provide s quantitative evidence of the greater extent of so rption of thi s solute. With both visual and quanti tative interpretation of this experiment, s tudent s grasped the impact of so rption and the connection between this partition ing proce ss and the potential for exposure to contaminants through drinking water downgradient of a pollution so urce. DISCUSSION AND CONCLUSIONS Student s completing the se experiments observed the wide variability in the behavior of organic pollutant s in the envi ronment. They concluded that the mobile green so lute and the bulk organic liquid that compri se d this NAPL were hy 44 blue green Figure 4. Photograph of the co lumn retardation experi m e nt after t we l ve hours. The polar green so lut e clearly travels at a hi g h er veloci t y than th e blue 200 ,--------------------, 150 E .s Q) 100 u C "' U) i5 50 BLUE 0 GREEN o o 500 ooo 1500 2000 T ime [m i n] Fig u re 5. Calculation of retardation coefficie nt s fro m mea sured average distance of so lut e tra ve l as a function of tim e. Solid lin es represent th e lin ear regressions and erro r bars illustrat e one standard deviation of the four indi vidual measurements of distance at eac h tim e Chemical Engine e ring Education

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drophilic and very mobile in the e nvironment. The so lute and bulk organic liquid that compri s ed the red NAPL on the other hand, were ve ry hydrophobic and relatively immobile in an aquifer system. From a pedagogical standpoint, providing students with an active learning experience and very visual observation of these phenomena effectively improved their overall under standing of the fate and transport of organic contaminants in an environmental system In terms of Bloom 's hierarch y of learning 141 the first laboratory increa sed the st udents co preh ens ion while the second laboratory a ddre ssed the appli cation of these ideas in engineering calculations Both com prehension and application are critical ste p s for the students to achieve prior to advancing to the more challenging ta s ks of analysis and synthesis Thus, by completing these labora tories early in the se mester students were better prepared for tackling more complex issues associated with formulating engineering decisions with respect to the potential for envi ronmental contamination ACKNOWLEDGMEN T S Support from a National Science Foundation CAREER grant (BES-9501567) was used in developing the se laboratorie s. REFERENCES 1. Cohen, R.M ., J W. Mercer and J. Matthews DNAPL Sit e Evaluation C L. Smoley Boca Raton FL ( 199 3) 2. Thibodeaux L.J. Environm e ntal Chemodynamics: Mov m e nt of Ch e micals in Air Wat e r and Soil 2nd ed ., John Wiley an d Sons New York NY ( 1996 ) 3. Verschueren K., Handb ook of Environmental Data on Or ganic Chemicals 2nd ed., Van Nostrand Reinhold New York NY ( 1983 ) 4 Wankat, P C. and F S Oreovicz T eac hin g Engine e ring, McGraw-Hill, New York NY ( 1993 ) 5. Colour Ind ex, 3rd ed. The Society of D yers and Colourists, Bradford England ( 1971 ) 0 COMET Projec t Continued from page 23. for introducing these topic s. As the instructor I should have made more clear to the students the connections between the project and the course material I also should have explained why the project i s of value to a beginning engineer. Clearly s tated instructional objectives are known to facilitate st udent Iearning _f 10 J The project might have been more closely linked to the main course content if for example, it had permitted chemical energy sources and involved more energy balance calcula tions in the COMET design. But thi s would h ave been diffi cult since the project had to be safe and relatively short and simple for sophomore students. The COMET project is there fore a compromise that achieves the primary goal of introWint er 1998 ducing idea s not found in traditional pencil-and-paper projects but does so in a non-chemical engineering-specific format. Logistical Improvements I think this proj ec t would hav e b ee n b e tter at the beginning of th e quart e r. " Gi ve th e g roups an ex tra week or so t o think about the pr o j ec t ." Mak e th e pr o je c t wo rth m o r e than 5 %." A number of s tudent s would have preferred different lo gistical arrangements for the project. Becau se it involved a lot of work, st udent s wanted the project assigned earlier in the quarter when it would not conflict with midterms, wanted more time to work on the project and wanted it to be worth a larger fraction of their grade. All of the se changes can be easily made and will be implemented next time. CONCLUS I ONS The COMET project pro vi ded a relatively s imple assign ment that introduced so phomore chemical engineers to a number of important engineering concepts that are often not addressed until later in the curriculum: teamwork open ended problems, design hand s-o n experimentation, techni cal writing, and estimation based on limited data Most stu dent s enjoyed the project and recommended its use in future classes. ACKNOWLEDGMEN TS Thanks to Melissa Bradley Richard Felder, and David McGill for helpful di sc u ssio n s and to Dayton Funk for pho tography. This work was s upported in part by a CAREER Young Investigator Award from the National Science Foun dation (BES-9624832) REFERENCES 1. West, W ., W. Flowers and D Gilmore Hands-On Design in Engineering Education: Learning by Doing What ?" Eng. Ed ., 80 560 ( 1990 ) 2 McConica, C. Freshman D es ign Course for Chemical Engi neers, Ch e m. En g. Ed. 30, 76 ( 1996 ) 3. Davies W.A. D esign Competition for Second-Year Stu d e nts ," Chem. Eng Ed. 30 102 ( 1996 ) 4. Felder, R.M ., and R.W. Rousseau Elem e ntary Prin cip l es of Ch e mi c al Pro cesses, 2nd e d ., John Wiley & Sons New York, NY ( 1986 ) 5. Angelo, T.P. and K.P Cross Cla ss room Assessment T ec h niqu es : A Handbook for Coll ege T e achers, 2nd ed Jossey Bass San Francisco CA ( 1993 ) 6. Bell J .T., "Ano nymous Quizzes ," Ch e m Eng. Ed ., 31, 56 ( 1997 ) 7 Schmeck R.R. ed., L e arning Strategies and L ea rning Styles Plenum Press New York NY ( 1988 ) 8. Felder R ., "Meet Your Students : 3. Michelle, Rob and Art," Ch e m Eng Ed. 24, 130 ( 1990 ) 9. Felder, R., Matters of Style ," ASEE Prism, 6, 18 ( 1996 ) 10. Mager R.F ., Pr e paring In structional Obj e ctives, 2nd ed ., Lak e Management and Training Belmont CA ( 1984 ) 0 45

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Ra n dom Thought s ... SHIPS PASSING IN THE NIGHT RICHARD M. FELDER North Carolina State University Raleigh NC 276957905 Ever get a s neaking suspicion that our students may not be totally focused on the intellectual delights of thermodynam ics and transport phenomena while we're lecturing? It some times happens that other things are on their minds, especially when we're enthusiastically filling the board with letters numbers and squiggles that have no apparent connection to anything they know or care about. For example, Professor Cheever: .. an d next we'll examine laminar flow of a n ewton i a n fluid in a circular pipe and derive Equa tion 4.5 35 in your text. We first draw this differen tial element . and now we itemize the stresses acting on it, starting with ... St ud ent A (SA): "Hey Jerry how's the rest of your schedule look?" SB : "Not bad-I've got a couple of humanities courses so I shouldn't be overworked." SA : "Un l ess you get old Ferguson .. last spring she gave us five books to read in the first week, including Moby Dick. It's about a fish." SC : "What did he say that arrow pointing up is?" R i cha r d M. F elde r is Hoechst Celanese Pro fessor of Chemical Engineering at North Caro lina State University He received his BChE from City College of CUNY and his PhD from Princeton. He has presented courses on chemi cal engineering principles, reactor design pro cess optimization, and effective teaching to vari ous American and foreign industries and institu tions He is coauthor of the text Elementary Princip l es of Chemical Processes (Wiley 1986) Copyright ChE Division of ASEE 1998 46 SD : "Who know s? ... I ju st wonder how I'm going to make it to Decemb er if I'm this lost now. SC: "You and every body else .. except mayb e old Arthur her e . H ey Art-you ge tting this?" SE: "No, but I've seen his old tests-you don 't need to und erstand anything you just need to plu g into formulas." SD: "Cool!" P r ofessor Cheever : ... an d as we know from calculus, the limit of this expression as delta r approaches zero is what? ... anyone remember? ... no? ... well, it's the partial derivative, and so we can replace ... SF : "W hat say, Chief-coming to the Delta Chi mixer tonight?" SG: "No can do-I got a ph ysics test tomorrow and if I don t get my grades up I can kiss my scholarship goodbye SF: "Aw, come on, Sir Isaa c-you know that stuff A couple of brews and you' ll be relaxed and ready to hit that test like a sledge hamm e r. SG: "That's what yo u said before the chemistry final last spring and if I remember right you relaxed your butt into a D ." SF: "Yeah, but that final was ... SH: "So how'd it go last night?" SI : Don 't ask ... that geek Rachel set me up with is majoring in soil science or something and he spent the whole night talking about fertili zer. Let me tell you a Chemical Engin ee ring Education

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few t hin gs about phosphorus that yo u probabl y never . Professor Chee v er: Now at this point we introduce th e s tr ess tensor a con v enient and conci s e repr ese nt a tion of th e nor mal and s hear s tre ss e s in th e ... SJ: "Yo Sally-hand me some of th e m c hips th e re SK : ... P roblem 3 on the th e rmo hom ewo rk ?" SL: Y ea h it 's a killer, but it's c ut e-yo u hav e to figur e out the equilibrium partial pr ess ur e of nitrous oxide to know if the dental hygieni s t poi so ned the bank pr es dent. SK: R ight, I figured that mu c h out but at that pressur e y ou can't just plug into R aoult' s law and I don t how how y ou .. SJ : "Yo, Gen e, can I have a hit of yo ur Dr. P e pp e r ?" SM : What time y ou gotI think this ha s been go ing on for about four hours but I'm not sure." SA: "Twenty m i nutes to go and c ountin g SA: "Ten minutes." SN: "Shh-don't wake B renda .. s h e's the o nl y one getting an y thing useful out of this class." SO: I t 's m y grandmother this tim eI'll probably ha ve to go home for th e weekend again and just h o p e I can find some time to l ook over th e ... SJ: Yo Bruce hand m e a couple of them Ch eez Doodles wou l d ya?" SQ: H ear about Monica, Sh ei la' s roommate ?" SR: "No, what about h e r?" SQ: She 's been acting weird lat ely, just l y in g in her room s tarin g at the ceiling for h o ur s." SR: Sounds bad ." SQ: "Gets worse-someone found her passed out next to an empty pill bottle yesterday. Sh e ila saw her at th e hosp i tal today and t h inks she'll b e all right but she still looks kind of green." SR: B ummer! That s like what happ e n e d to R ud y last ye ar only inst e ad of poppin g pill s h e ... SA : One minut e ST : ... ok, no w her e in Probl e m 4 what I think we need to do is ... SU : ... so the hors e says to the c hi c k e n .. S J: Yo, Angie l emme ha ve a cou pl e of those M&M 's 1 like the orange ones." SV : .. and at lea st we got to do something in thos e class exerc is es Fur ze was always g i v in g in m ec hanicsyo u make m e sit for an hour w ithout doin g an y thing and I m ... SG: ... no, we' re going down to the bea c h Frida y right after class-tell Ja c k and Ella we' ll meet Monda y afternoon in the loun ge and finish that report, and then we c an ... SE : .. but that correlation only wor ks at low concentra tions. Ma y be if we . S W (laughing ): "That's a good one .. did y ou hear th e o n e about the rabbi the pri es t and the c hemical eng in ee rin g professor w ho were on a ... SX: ... and h e's r ea ll y mad and told Mom that he 's not go in g to pa y m y tuition any mor e so I ma y have to find a job, and I don t think I can stay in school and work e nough hours to ... SY : "Hey Cindy how about asking him if we're respon sible for this stuff on the ex am I love the faces the y make w h e n yo u ask them that. SA : .. and th e re s th e bu zze r and I'm out of here." S Z: Yo Vinnie, brin g your bo ok to th e K eg tonightI got a few questions about Eq. 4 .5-237." SJ : H ey, no problem-that one's m y favorite. Come on l et's grab a burg e r and fri es a c ross th e street befor e we go to the .. Pro fesso r C h eeve r : ... a nd no w if y ou s ub s titut e th is ex pre s si o n for th e friction t e rm y ou e nd w ith E quation 4 5-35 Eve r y bod y under s tand ? Good see y ou Frida y SA: And the point of all that is ?" S Z : B eats m e 0 A ll of th e R andom Thoughts co lumn s are now avai l a b le o n th e Wo rl d W id e Web at http : // www2 n cs u edu/effec ti ve_teac h i n g/ a nd at h tt p : // c h e u fl e du/ ~cee / Winter 1998 47

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.,a_5_3._1_e_a_r_n_i _n..:g:.._in_,_n_d_u_s_t.....:ry:.._ ___ ) r This column provides examples of cases in which s tudent s have gained knowledge, insight and experience in the practice of chemical engineering while in an industrial setti n g. Summer interns and co -op assignments typify s u c h experiences; howev er, reports of more unusual cases are also wel co me. De scriptio n of analytical tools u sed and the skil l s de ve lop ed durin g the project s hould b e emp ha size d These examp le s s hould s timul ate innovative approaches to bring real world tools and experiences back to campus for integration into the curriculum. Ple ase s ubmit manu sc ript s to Profes sor W J. Koros, Chemical Engineering Department University of Texa s, Austin Texas 7871 2. \. MAKE SUMMER INTERNSHIP A LEARNING EXPERIENCE GARY S. HUVARD 12218 Prince Philip Lane Chesterfield, Virginia 23838 M any engineering undergraduates have the oppor tunity to work on one or more s ummer internships before they graduate. In principle the s tudent s are paid to s pend the summer learnin g how engineering project s are carried out in the real world Time out for a reality check. Without s ignificant planning by faculty, the chances of an under gra duate summer intern actually learning something u sefu l are not very good. Unlike graduate s tudents who usually r ece ive project s consistent with their research expertise, undergraduates are often s im ply parceled out to various plant s or R&D facilities. Rarely are faculty members involved in s ite or project choices; no one really know s what the st ud e nt s will end up doing and there is rarely any follow-up to find out if they learned anything of substance L et s review how thi s proce ss often works. Sometime around March or April so meone on the faculty s tart s phonGary S. Huvard earned a BS in Chemistry from Campbell College ( 19 74) and a PhD in Chemi cal Engineering from North Carolina State Uni versity (1978). He spent eight years with the Corporate Research Group at BFGoodrich (Brecksville, Ohio) and three years with du Pont's Tyvek Technical organization (Richmond Vir ginia) before establishing a private practice in 1989 Since that time he has worked with more than 20 different companies on projects span ning the breadth of ChE practice. ing indu s trial contacts-usually r esearc h director s or plant manager s -with questions like How many kids ca n you take thi s year? " Can't you s queeze just one mor e s lot out of the budget ?" The director comes up with a number and the faculty advisor jots it down and continues to mak e calls until the available slo t s match the number of s tudent s wanting intern s hip s that s umm e r. On the indu stry si de a hand-off then takes place. The logistic s of getting the st udent s in getting non-di sclos ure agreements signed, arranging so m et hin g with Accounting and so forth is pa sse d to the Human Re so urce s Depart ment. Around the first or seco nd week of May the HRD calls the director (o r whoever) to inform him or her that everything is se t and th a t 2 (o r 4 or whatever) st udent s will be arriving on June 5 Now the real plannin g starts. Th e director imm e di ate l y begins sca nnin g a li s t of technical per so n s, identif y in g lik e l y candidates to s up e r v i se a s umm er intern. The scie nti sts cho se n are r e que s ted to s ubmit by Friday at the late st, a descrip tion of The Proj ec t. On Wedne s da y afternoon the a bout-to-be intern s uper vi so r s earnestly look for a gas c hromatograph and a di scar ded 286. Being experienced indu s trial sc ienti s t s, the y are well aware that any engineering st ud e nt can be safe l y a nd harm l ess ly occupied for at l east three month s so lon g as The Project entails one of t wo ac tivitie s : Copy ri ght ChE D iuision of ASEE 1998 48 Chemical Engineering Education

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Project #1, Description Optimum functionality of our proprietary XLR34 R ecom binant Distillati on Pro cess requires a comp l ete understanding of the quaternary splits of all com pon ents throughout the co lumn int e rnal s. Th e summer intern will be used as suggested by our Total Quali ty Mana gement Lif e Cycle Engineering guide lin es, as a resour ce to s peed up the analysis of tray to-tray h ydrodyna mi cs in the XLR34 downcom e rs. Th e data will b e used t o build a simulation (see The Proj ect#2) of downcomer flow stability n eeded for optimum eco nomic ROI. T r anslation I'm going to have the kid stand in front of that old CC for three months injecting samples and r ecording p eak areas. Aside from stabbing himself with the needle, there is virtually no way the student ca n get hurt and I'll never have to deal w ith the safety peopl e or do any of their pape,work. Plu s, he ll hav e an enormous pile of numbers to plot and tr y to make sense of which will keep him out of my hair for three months and give him at least six overheads to present in th e project review in August. Pr oject #2 Desc r iption The E cono mic Viability Indi ces for ou r propri etary XLR34 R ecombinant Di stilla tion Pro cess are very d e p e nd ent on down comer h y drod ynam i c functionality In order to maximi ze the R&D In vestme nt Ind ex, as suggested b y our Total Quali ty Manag e m en t Lif e Cycle Engineering guidelines, it is critical that fluid dynamic computations be ca rried out to mod e l the flow striations pr ev iousl y des c ribed in our Proj ect Monthl y dated 2/9. A su itabl e computer system has b een procured for use by the summer intern. Our goa l will be to develop a proprietary computer simulation to describe these striations. In future communications, this pro gram will be code-named Pro g ram XLRC to minimi ze the potential that in-kind compet itor s recogni ze our activities. Tra n s l ation We found an old 286 that nobod y was Winter 1998 using and set it up in the come r of the high bay. Since any program has to be written in QuickBasic to run on this thing it shoul d take at least three months to get anything wo rkin g. Aside from eye strain ther e is virtually no way the student can get hurt and I'll never have to deal w ith the safety p eo ple or do any of their paperwork. Plu s, there will be an enor mous pil e of code to write and try to debug, whic h will keep this p erso n out of my hair for three months and give him or her at l east 6 overheads to pr esen t in Th e Proj ect R eview in August. Be st of all, by September JO nobody on earth w ill remember w hat XLRC means, and I can bury the w hol e business and get on with my life. The Research Director, having received the project de sc riptions in a timely manner passes them on to the faculty advisor. The advisor is quite pleased These s tudents will really l earn so mething thi s summer! (Not!) We have just described two very successful s ummer internships. I have per so nally witnessed dozens of them From the s tandpoint of the Re searc h Director and the company, the stu dents came in worked on something presum ably useful to the company, and left without having been physically altered Too bad no one thinks to ask the intern whether he or she actu ally learned anything u se ful. To be fair, we should point out that many companies make an admirable effort to identify appropriate intern project s. In these companies, project ideas are solicited and reviewed by s taff engineers (possibly a s pecial committee) prior to intern assignments. Rarely however do pro fessors take part in these reviews. W h i l e ma n y companies conduct on-campus interviews for summer intern s, the re s ult s may be unde s irable since the profes so r s, aga in are left out of the planning proce ss Unfortunate l y few pract i cing engineers are able to assess whether a given project is appro priate for an undergraduate chemical engineer ing student. To test this, just ask a few indus trial co ll eagues to submit problems for the sophomore mass and energy balance course. Don't be surprised if ma n y of the problems are far too difficult for st udent s at thi s level. We Without significant planning by facul ty, the chances ofan undergraduate summer intern actuall y learning something useful are not v er y good. Rarel y are faculty members i n v ol v ed in s ite or project choices ; no one r e all y knows w hat the s tudents will e nd up doing and there is rarel y an y follow-up to find out if the y learned anything of substance 49

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easily forget how hard those problems once seemed. A BETTER WAY Setting up meaningful summer internships for your stu dents is possible. But, it takes commitment by the entire department and continu ing effort. If you really want your students to learn something useful try following the route outlined below. Establish Contacts with Engineers, NOT with Managers It mu s t be very tempting, given everything else you have to do to simply place that once-a-year call to the R&D Director. Unfortunately, many R&D Directors I have known don't have a clue on how to define a good internship prob lem. But if you make the effort to befriend the engineers who actually do the technical work, you can make dramatic progress toward the goal of finding truly excellent summer intern problems. The hard part is finding the right engineers. In addition to using whatever contacts you already have (alumni are excellent contacts), try sca nning the programs from recent AIChE meetings for industrial participants who either wrote or co-wrote papers. Chances are good that a phone call and short pitch to these contacts will unearth a number of people interested in working with so meone from the univer si ty. Generally, engineers will not have the authority to grant internship funding. If their company is not in the habit of hiring summer interns you may need to help the engineer outline for management the economics of s pon so ring one or two interns. To do thi s, e-mail or fax the engineer a single page showing the approximate cost for having a s tudent on site for three months It should include student sa lary travel reimbur se ment and housing if appropriate. Sell the Program Once you have a commitment from the engineer, get the name and telephone number of the appropriate manager and place a call to that person. Be prepared to wait one to three months (or more) for management approval; virtually noth ing is done in industry without having one or two meetings. Expect the manager to say something like "Le t me get together with Bob and some of the other engineers to discuss this first and I' II get back to you later. Always get a firm date and time when the manager will "get back to you." If they don t contact you within a rea so nable amount of time and often they won't, get back to them A certain amount of nagging can be productive. Managers like to perceive benefits, tangible and intan gible, for any and all money they spend. And, you are asking them to spend money on something they haven 't been con vinced they need or want. To this end, have a list of potential 50 benefit s handy Mention such things as In creased productivity without a fixed cost on the balance sheet. Students are well trained and might bring in new ideas and techniques. Students often accept positions after graduation with th eir internship sponsors. This can help hold down recruiting costs. Publi cations that result from internships reflect well on the sponsoring company and its management. The sponsoring engineer wi ll ha ve b ette r access to the university and any technical or recruiting help the faculty might provide in the future. Ifit sounds like I'm telling you to "se ll" internships, I've made my point. That is precisely what you are doing and exactly how you s hould approach the activity. It need not be a hard se ll; the best sponsors, long-term, will be those who buy enthusiastically after a soft pitch. All you want i s a commitment and a letter from that manager supporting the internships. Once you hav e thi s commitment in writing, whether obtained through the engineer or by directly ap proaching management you are in a position to sta rt defin ing the problems. Defining the Internship Problems You will always know far more than your engineer-spon sor about the capabilities of the st udent s and the type s of problem s that would be suitable for them. But the engineer sponsor knows far more about his or her process than you know and, therefore presumably knows what the problems are. So, in thi s phase you s hould have two goals: 1) Learn about the process so you can help define appropriate problems. 2) Teach the engineer-sponsor what he or she needs to know to suggest appropriate problems. The first goal above should be a s hort-term activity. If possible, visit the plant or R&D center to learn about the process yourself; do not assume that the engineer-sponsor fully understands the proce ss. Chances are there are many aspects of the process that are not considered problems" simply because they aren't presently troublesome I have never encountered a proce ss that couldn't be improved in dozen s of ways if someone simp ly paid so me attention to the aspects that weren't "pro bl ems Many such improvements could result from a three-month internship study. Since the cost of the internship is relatively low and the return on such improvements i s usually rapid and measurable, it is easy for the company to justify the work. But someone has to clearly point out potential improvements or they will continue to go unnoticed Chemical Engineering Education

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The second goal (training engineers to define good in ternship projects) is a long-term investment in your pro gram. After expending considerable time and energy to de velop sponsors, you would like to retain them for many years and, as quickJy as possible, reach a point where the engineer-sponsors can suggest suitable problems without your assistance. Good internship problems have certain distinguishing at tributes: [I The problem can be approached by a junior or senior chemical engineering student and solved (or good progress can be made) using skills that students at that level can be expected to have or to easily acquire. The analysis or design of a single unit operation is usually appropriate. As an ex ample, suppose a plant has a rotary dryer that uses preheated air for drying, but there is no recycle of the exhaust. How much money could be saved by recycling some of the hot exhaust air? Would the product quality be the same if the dryer is operated at a higher humidity? Would productivity suffer? How much capital investment would be required? Should this change be made? Even though the dryer perfor mance is currently "acceptable," the operation might be wasting a substantial amount of energy An analysis of this dryer would make a great three-month intern problem. The solution requires mass and energy balances, understanding relative humidity and psychrometric charts, basic equipment cost estimation, and basic economic-return calculations. Some experimentation might also be needed but chances are old company reports will have drying curves for the product at different conditions of temperature and humidity The stu dent will then also get some practice in doing an internal literature search [I The problem can be completed ( or really good progress can be made) during the time allotted to the internship. Don't minimize the importance of this attribute Students quickJy become demoralized if they begin a project and then discover they cannot possibly complete it. They find it em barrassing and often discouraging to have to give the cus tomary end-of-internship talk to the technical staff on a half completed project. For example, an analysis of the entire heat exchanger network in a large plant cannot be carried out by anyone in three months, but an intern could analyze the performance of one small network of heat exchangers (three or four) in that time. [I The sponsor should have already obtained any needed data that cannot be collected in the first month of the study For example, the analysis of a batch polymerization reactor might sound like a good project, but chances are that the sponsor does not have the necessary kinetic data for the analysis. (If the data existed someone would have already done the reactor analysis.) If you assign this problem withWinter 1998 out reviewing the available data, you may doom the student to a miserable summer. The intern may spend the entire summer waiting for analytical equipment to be delivered or, worse spend the summer trying to get an ancient GC work ing that never will. [I The project should test and stretch the student's engi neering skills. Does the project require mass and energy balances to be written and solved? Is statistical analysis of data required? Does the project require the student to learn some new chemistry? Are periodic written progress reports required? Is a literature search needed? Beware of project ideas that begin with We could sure use some help getting the data we need on Project GruntWork .... "-it is a sure bet that your student will spend three months standing in front of some infernal apparatus testing one sample after another. The intern learns NOTHING from this type of activity If a company just wants some data taken, it should hire a temp. You can do better for your students. [I The intern should be safe while working on the project. Most engineer-sponsors will go to heroic lengths to guaran tee the safety of their interns. Nevertheless, you should, if at all possible, look over the sponsor's shoulder on this issue. Ideally, your program teaches industrial safety as an integral part of the chemical engineering curriculum and your stu dents are capable of auditing their own work environments. Give your students practice before turning them out by as signing safety audits as part of your unit operations and design courses. Complete the Cycle Defining appropriate projects will be far more time-con suming than arranging internships. Clearly one or two fac ulty members cannot do all the work. One good way to spread the work load is to get the students involved. Once given a set of guidelines like the ones above, there is no reason that small teams of students (three or four to a team) can't work with engineer-sponsors to draft lists of potential projects. If possible involve yourself in the review process. By observing the ability of your students to assess the project ideas you will quickJy find out whether they have learned the material you ve been teaching. In this way, you can help each class identify new projects and problems for the classes to follow. In addition to learn ing to identify those "hidden process improvements de scribed above your students will be learning teamwork, proposal preparation communication skills, salesmanship, and, hopefully, a bit about obligations to future generations. A C KNOWLEDGMEN T S The author would like to thank Prof. R.M. Felder for his helpful revisions and editorial contributions. 0 51

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(.3 .. 5-._c_u_rr_i_c_u_l_u_m __________ ) AN INTRODUCTORY ChE COURSE FOR FIRST-YEAR STUDENTS KENNETH A. SOLEN, JOHN N. HARB Brigham Young University Provo, UT 84602 F reshman s tudent s who h ave an interest in c h emical engineering have several important needs that we feel should be addressed. First, many of them are s till undecided about their major and need help making that decision Second, these students need to receive instruction that provides a broad, integrated perspective to serve as a foundation for subsequent classes. Finally, first-year s tu dents need to experience s upport and encouragement from faculty a nd other students. In s pite of these need s, chemical engineering departments tradition a lly have done relatively little for these students, often relegating them to a generic computing cla ss or to a generic freshman engineering class. For example, for many years at BYU the only "chemical engineering" courses taken by first-year students were a course in FORTRAN program ming and a 0.5 credit freshman seminar. But we have re cently changed our curriculum to better meet the need s of these s tudents; among those changes ha s been the development of a new introductory course-the subject of thi s paper GOALS FOR THE COURSE We began development of a co ur se for first-year students with several distinct goals in mind (summarized in Table 1) with the most important of those goals being 1. To provide knowledge about th e chemical engineering field to help students select their major. 2 To provide an integrativ e foundation for future courses We wanted to provide sufficient information about the discipline to enable s tudent s to make an educated deci s ion regarding their choice of a major. To meet this goa l we fe lt it was important for the st ud e nt s to experience c h emical engineering reasoning calculations, deci s ions, and applica tions. These experiences sho uld include an introduction to some of the fundamental principles and equations (e.g., Fick's Law Fourier's Law etc.). To increase learning a nd int erest, we also wanted to help stude nt s und erstand the impact of chemical processing on their own lives and to understand the connection between chemical engineering and their "eve ry52 day experiences. We felt that it wa s important for the stu dents to eval u ate and draw conclusions from numerical re sults as would be typically done by a chemical engineer. Further we wanted to expose students to "design" problems that were open-ended and had multiple solutions. Finally we wanted the material to cha ll e n ge the students in order to stimulate their interest and to provide them with a sense of the curriculum 's rigor. Thi s la s t goal was motivated in part by our prior experiences with s urvey courses that fai led because they did not offer much intellectually to the st ud ents entering o ur department; stude nt s felt that suc h courses were neither challenging nor informative and were essentially a waste of their time We wanted thi s course to play a significant role as part of our undergraduate curriculum by providing a foundation and perspective for subsequent classes. It has been our observa tion that sophomores, junior s, and even seniors so metime s view each course in their program as an isolated entity, unrelated to the other subjects they have st ud ied. Instead of building on pa s t l earning, they often see m to start over with each new s ubj ect. Hence, they frequent ly fail to see the discipline as a whole until very late in their program (if at all). Therefore a key o bj ective of our co ur se was to provide Ken Solen is Professor and Department Chair of Chemical Engineer ing at Brigham Young Univer sity. He received his BS in Chemical Engineering (1968) from the University of California at Berke ley and his MS in Physiology (1972) and his PhD in Chemical Engineering (1974) from the Univer s i ty of Wisconsin. He conducts research in bio medical engineering and artificial organs John Harb is Assoc ia te Professor of Chemical Engineering at Brigham Young University He re ceived h is BS ( 1983) from Brigham Young Uni versity and his MS ( 1985) and PhD ( 1988) from the University of Illinois Urbana all in chemical engineering. His research interests include elec trochemical engineering and mathematical mod eling of complex physical systems Copyright ChE Diuisio11 of ASEE 1998 Chemical Engin eering Education

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an integrated overview, offering a bro ad perspective and serving as a framework upon which s ub se quent courses could be built. That objective included helping the st udent under stand where subsequent chemical engineering courses fit within the larger perspective as well as how knowledge obtained from other discipline s (e.g., c hemi stry, math phy ics, economics, etc ) is essential. In a figurative se nse the introductory course would create a "ske leton b y broad s hal low coverage of the discipline and later courses would add the meat to that skeleton. Additional goals were related to the socia l needs of the students. It is our opinion that first-year s tudents s hould have close interaction with the faculty While so me interaction is facilitated by faculty-student socials required meeting s with advisors, etc ., our course provide s man y more faculty-stu dent contact hours than any other method Of equal impor tance to faculty-student interaction s are interactions between the s tudents them se lves One of our goals for the introductory course was to help develop a "co mmunit y of chemical engi neers" through the use of learning teams and group activities CONCERNS of the potential advantages that it would offer our s tudent s, provided that the course was designed to minimize the re so urc e requir e ment s associated with it. Consequently, the course was designed as a two-credit-hour one-semester course without a laboratory (eve n though we recognized the va l ue of a laboratory experience for our be g inning s tudent s) Two credits were made available for the course as part of a genera l restructuring of the curriculum and the neces sary resources were allotted for development of the course. THE COURSE The goals listed in Table 1 had a sig nificant impact on the course 's str ucture during its development. In particular our desire to provide an inte gra ted overview required that the individual course topics be co nnected together in a logical fashion. Thi s integration was accomplished by struct uring the co ur se around an engineering design problem that could be solve d by de s igning a s imple chemical process. The en tire se me s ter and all the material presented in the course were dedicated to the de sig n of that process The problem-oriented sce nario begin s TABLE 1 There were several concerns that in tl uenced development of the course and led us to minimize the credit hour s and faculty resources associated with it. It was clear that a new course could not simply be added to a curriculum that was already overflowing, especially at a time when we were being encouraged to decrease the number of credit hour s in order to help students graduate more quickly. Thus inserting this course meant reducing the credit hours of more ad vanced courses, and some faculty ques tioned the value of such a trade. Also, since a large number of beginning s tu dents do not continue in the di sci pline after their fust year, there was concern that an introductory course would dedi cate resources to teaching Goals for an Introductory Course in ChE the first day of class when the s tudents are asked to imagine that th ey "a re chemical engineers working for the ABC Chemical Company ." The student engi neer r ece i ves a memo from his/her su pervisor reporting that the contractor who has been disposing of the hydro chloric acid by-product from "our manufacturing process is going out of business. The memo goes on to ask the s tudent to take responsibility for solving this problem and the remainder of the course is directed toward leading the s tudent to that so lution This design prob lem provides the framework for integra tion of materi a l presented throughout the students who would not graduate in chemical engi neering. Further the course we envisioned would need to be developed from scratch since a suitable text was not available, thus add ing to the required re sources. After some discussion the department decided to support the course because Wint er 1998 1. To provide information about the chemical en gineeri n g field and thu s e nable tudent s to knowl edgeably se l ect their major. 2. To provide an integrated overview of chemical engineering as a foundation for subsequent courses. 3. To teach significant chemical engineering prin ciples, including Fundamental concepts and quantitative rela tionships Connection s to the students' pa s t experiences Typical chemical e n gineeri n g calcu l ations and ana l yses Open-ended multi -so lution design problems. 4 To promote intera ct i on between fir s t-year s tu dent s and the chemical engineering faculty. semester. 5. To help develop a community of chemica l en gineers." The general topics presented in the course are s hown in Figure 1, with the CASE STUDY Fig u re 1. Schematic of th e topics covere d where th e length of each bar represents the time spent on the topic. approximate amount of time d edica ted to each topic in dicated by the length of the seg ment to which the topic title is attached. This two credit course is de s igned to be taught in fourteen weeks the length of a semester at BYU Written material de veloped for each of the top ic s has recently been com bined into a textbook,c' 1 with each topic forming a sepa53

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rate chapter. The table of contents of the t ex tbook s hown in Table 2, reflect s the detail a nd sequence of topic s treated in th e course The topic s are introduced on a "j ust-in-time basis as the s olution to the de sig n problem is developed throughout the semester. For example, after di sc u ss ing s trate g ie s for gener ating and evaluating possible so lutions the deci s ion is made to de s ign a chemical proce ss in which so dium h y droxide is used to neutralize the HCI. Materi a l balances are then taught in order to determine how much NaOH is needed Spre a sheets are also introduced as a n engineering tool. Th e s tu dents are th e n taught simple fluid mech a nic s to provide the ba s i s for delivery of the NaOH a nd HCI from the s torage facilities to the point of reaction This approach continues as is s u es are considered regarding mixing the acid and ba se ( ma ss tran sfe r i s tau g ht ), the volume of rea c tor needed (reac tion engineering i s introduced), and cooling the final product to an acceptable temperature for di s po sa l (e n e r gy balanc es and heat tran s fer are studied). The final ste p is an evaluation of the profitability of the propo se d proce ss (eco nomic s are introduced ). By the end of the se mester students have developed ski ll s in severa l of the s ubdiscipline s that make up chemical engi neering and have applied them toward the solution of an engineering design problem The se ski ll s repre se nt a u sefu l s ub se t of those that the y will l ear n in subsequent chemical engineering courses. In or der to illu s trate the level at which the material is pre se nted Table s 3 and 4 pro v ide examples of problem s used in the course a long with the appropriate so lution s as pre se nted in the textbook. Proce ss flow diagrams are u se d throughout the course to help the st udent s visualize how the different aspects of the course and de s i g n problem are connected. Student s are in troduced to the se diagram s and required to u se them very early in the se me s ter (C hapter 2) Th e n as each new topic is introduced and u se d to de s ign a n a dditional component of the proce ss," th e process flow dia gra m a nd stream table are updated to reflect the new a ddition and it s relationship to the previous components of the proces s. In contrast to the acid-neutralization de s ign problem the solution for which i s developed for the students throughout the se me ster, the co ur se also features a seco nd de s ign prob lem or case s tud y, to be so lved independently by student teams. Th e case s tudy de sc ribed in the la s t chapter of the book involves the isomerization of meta -xy lene to ortho xylene and require s the use of material and energy balances the s izing of a pump reactor and so me heat exchangers the preparation of a process flow diagram, and the completion of an elementary economic analysis. It is introduced near the end of the se mest er and provides the students with an oppor tunity to work together, to learn from each other, and to apply nearly all of the concepts and principle s they have learned throughout the se mester. Although new material is 54 pre se nted in class during the time that s tudent s are wo rkin g on the case-study assig nment the l as t few topic s ( particu larly engineering material s a nd proce ss control) are treated qualit a tively a nd briefly with minimal homework assign ment s, to give the s tudent s time to focus on the case study Student s are periodically required to inform their "s uper vi s or in writing concerning the progre ss made to d a te on the case st ud y, and a final de sig n report i s also required from each team. Th e xylene-isomerization case st ud y is the only TABLE2 Table of Contents Chapter I. The Assig11me11t 2. What is Chemical E11gi11eeri11g? What is Chem i ca l Engi n ee rin g? What i s a Che mi ca l Proce ss? Flow s heet s The Impact of Chemical Pro cess ing and Chemica l Engi n eeri n g 3. Solvi11g E11gineeriflg Problem s (W hat Shall We Do ?) Strategies for Solving Problems The Use of Team s in So l v in g Problem s 4. Describing Physical Quantities Units So m e Imp ortant Process V ar i ab l es 5. Steady-State Material Balanc es ( How Much Ba se Do We Nee d? ) Co n se r vation of Total Ma ss Material Balance s for Multiple Spec i es 6. Spreadsheet s (Ca lculating the Cost of the Ba se) The Calculation Scheme Setting Up a Spre a d s heet Graphing 7. Fluid Flow (Bringing the Bas e to the Acid) How Do F luid s Flow ? Pumps a nd Turbines: Examples of Fluid Flow Device s 8. Mass Transfer (Mix i11g the Aci d and Base ) Molecular Diffusion Mass Convectio n Mass Tran sfe r Through Boundaries Multi-Step Mass Tra n sfer 9. Reaction E11gineeri11g ( How Fast Will the Reaction Go?) Describing R eaction R a t es Designing the R eactor 10. Heat Transf e r ( Cooling Down the Product ) Energy Bal a n ces fo r Steady-State Open System s Some Applications of th e Steady-State E n e r gy Balance Heat Exc h ange Devices 11 Materials ( From What Shall We Build the Equipment?) Metals an d Corros i on Ceramics Polymer s Co mp os it es Stre n gt h of Materials 12. Controlli11g the Process Strategies of Pro cess Control H ow D o Computer s Talk to Eq uipm e nt 13. Economics (ls It All Worth It? ) Costs Profitability Eco nomi cs of the Acid-Neutralization P ro bl em 14 Case Study (Integrating It All Together ) The Problem Using Engineering Teams for thi s Case S tud y C h emical Engin eeri n g Edu c ation

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case study currently included in the textbook. Thu s, it ha s been reused from year to year, in spite of the ri s k that students may copy report s from previou s semesters. We have not found thi s to be a problem s o far, probably becau se of the honor code at BYU, but we do recognize the value of developing additional case studies for future use In order to teach first-year students with varying back grounds the course was designed with few prerequisite s TA B LE3 Example Used in Course Spe c ies A in liquid so lution (co n ce ntration=0. 74 M) e nter s a CS TR at 18 .3 Us where it i s consumed by th e irreversible r eactio n A C where r, eaction,A = k,c A ( k, = 0.015/s a nd CA i s in unit s of g m ol/ L ) What react o r volume i s n ee d e d so that th e co n ce ntr a ti o n of spec i es A lea v ing the reactor equals 0.09 M? The den s it y can be ass um ed to b e constant. SOLUTION (No te th a t th e s t e p s co rr espo nd t o the in s tructions in T ab le s 5.1 a nd 5.2.) Drawin g a di ag ram for thi s problem: l \n =l8.3L/ s cA;n =0 .7 4M ~A C reaction.A (0 .015/ s) CA volume=V v o ut = ? CA out = 0 09 M As outlined in Table 5.2, we wa nt t o co n str u c t a m o l e balanc e o n A. For thi s case (fo r a s in g le input a nd si n g l e o utput strea m ), th e mole bal a n ce become s fl A,in + rformation A = 11 A ,o ut + r consumption A Sp ec i es A i s b e ing consumed, but n o spec i es A is be in g fo rm ed, so r forma ti on A = 0. This along w ith su b s titutin g m ore co n ve ni e nt forms for the mol ar flow rate s, g i ves CAin +\/in =cA ou t Y out+ r consump ti o n A (a} The va lu e of the outgoing vo lum e tri c fl ow rate i s not s pecifi ca ll y g iv e n so we need a total ma ss b a l a nce which for a s in g le input and single output s tr e am i s min= m o m which, in mor e convenient term s, i s Pin Yin= Pout Y o ut Sin ce the den si t y i s co n s t a nt thi s reduces to Yin = Y o ut = V (b) W e ca n now ca lcul a t e r co n s umpti o n A u si n g Eqs. (a) a nd ( b). Eq u a ti on (a) b eco m es r A=CA V CA V =(cA -CA )v co n s umpti on in tn o ut o ut in o m = ( 0.74 g : o l -0.09 g:o l J( 18 .3~ j = 11. 9 g n :ol Up to now every thin g we ve done i s a repeat of the material balance s we l ear ned in Chapter 5 The n ew s tep i s to e qu ate the r co n s umption A term to the g i ve n rate ex pre ss ion time s th e reactor vo lume where cA ( in the reactor) = c A o ut rcon s umption A = (krcA o ut )v or V = f co n s umpti on,A = krCA out Wint er 1998 11.9 gmol/s = 8,800 L 0.015 009 gmo l s ~ L -) Specificall y, we did not assume any previou s exposure to calculus. We also assumed only a minimal knowledge of chemistry, s uch as pro v ided b y even a mediocre highs chool chemistry cla ss. Finally while the course requires minimal computer word-processing experience, it does not require prior exposure to computer spreadsheets. There are seve ral other aspect s of the day-to-day operation of the course that may be of intere s t to the reader. For example, the course include s frequent u se of group activi tie s, which se rve to hold s tudent interest increa s e learning effectiveness and help fust-year students form friend s hips with one another. In-cla ss quizze s are also u se d to motivate s tudent s to keep up with their learning (a particular problem for many first -ye ar students who developed the habit of last minute cramming in high school). Classroom demonstra tion s and examples from everyday life are used to illu s trate the chemical engineering principle s being discussed. Small piece s of equipment, s uch as pump s and heat exchangers, are partiall y di sasse mbled and passed around durin g class for students to examine; photograph s of larger equipment item s are al so u se d. Outside the classroom, we assign reading questions to be answered for each new reading assignment before the mateTABLE4 Example Used in Course A heavy o il s tream must be h ea t e d to a hi g h e r t e mp era tur e so th e decision is made to u se a heat exchanger with sat u ra t ed steam b e in g co nd e n sed to saturated water as th e h eati n g so ur ce o n the ot h er side of the exc h a n ge r. Th e c h arac t e ri st i cs of th e o il are Oil mass flow rate: 960 lb m/mi n Oil m ean h eat ca p ac i ty: 0.74 Btu / lbm F Oil inlet t e mp erat ur e: 35 F D esire d o il o utlet temperature: I I 0 F The sat u rated s t eam has th e fo ll owing properties : Steam t emperat ur e: 280 F H eat of vapor i za ti on (@28 0 F) : 925 Btu/lbm What s t eam flow rate is needed for thi s exc h anger ? SOLUTION Saturated s team =E=t: Saturated wa ter, 280 F riti, eam 280 F, riist eam Oil, l 10 F, 960 lbmlmin Oil 35 F 960 lb mlm in For thi s problem, th e o il is th e co ld st r ea m an d the s te am/wa ter is the h o t stream. Fo r th e o il s id e, Eq. I 0.24b gives Octu ty =[mc\(T out -T in ) L = ( 960 ~ )( 0.74~ )( 1 I035 F)=53,280 Btu mm llim~ = For the s t eam/wa t e r s id e, as indi ca t e d in T ab l e 10 .2, for condensation L',H pha se c hange = -L',H vaporiza ti on so Eq. (10.24c) g iv es -Qdut y -53,280 Btu /min 57 6 ~ n ffi s team =-. = -Af1vap -925Btu/lbm mm 55

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rial is discussed in class, and we assign homework problems for the material after it has been discussed in class. Other course features include the case st udy which ha s already been described, two mid-term examinations and a final exam. Grading is performed according to predefined criteria in order to encourage cooperation between students. As mentioned previously this introductory experience is completed in a two-credit-hour one-semester course. Thus, the resources expended are relatively minimal while our experience indicates that the benefit derived is significant. RESUL T S We have now taught the course for four years, and student response has been very positive At the end of every semes ter, all courses in our department are subjected to a student evaluation questionnaire, which includes numerical scores to specific questions and the opportunity for students to make unrestricted comments. The numerical scores for the introductory course have consistently corresponded to an overall rating of "excellent" and are among the highest in the department. We also se nd a questionnaire to all students who change their major from chemical engineering to another discipline. The comments from both of these types of ques tionnaire s, along with feedback during informal conversa tions indicate that students feel they have a much better understanding of and appreciation for chemical engineer ing after having taken the course. Some comments from those surveys are: The course gave me a good idea of what to expect in m y major." "The c ourse is much more applicable to a business or real-lif e situation than any course I hav e taken. "The co urse was EXTREMELY helpful in my decision to stay with Chem as my major. "The c ourse has given me a good idea of what Chemical Engineering is about." I really enjoy this co urse. If it were up to my c h emistry class I would drop out of Chem. But this course shows the light at the end of the tunnel." Good prep (sic) for m y major applies concepts and possible real life situations, but not too far over ou r heads." "Ch 1 70 [ was a] good class-I just knew after that one that I didn t belong. " I enjoyed Ch J 70 but J wouldn't lik e to do it for a career In some cases, that knowledge has resulted in students chang ing majors to something other than chemical engineering. That decision is judged to be positive if made with adequate knowledge and experience. The course appears to have slightly increased the overall retention of students in the chemical engineering program but that is difficult to verify at this time. The difficulty arises because approximately 80 % of the first-year students in our 56 program leave the university after the first semester or after the first year to serve a two-year mission for the Church of Jesu s Christ of Latter-Day S ai nt s. Some of those s tudents take our introductory course before leaving while others take it after returning Those students who took the first-year course in the last three years and then began servi ng their missions have not yet returned for a full year of sc hool so we are not able to determine if they will continue in the program. Where there are complete data we have examined reten tion as defined by the percentage of first-year st udent s who eventually but not s imultaneously took the subsequent course in our program (o ur sophomore course in material and en ergy balances ). During the five years before implementation of our course, freshmen took FORTRAN programming as the first-year course, and 40 % eventually took the sopho more class. During the last four years the new course has been offered in both the first semester (enrollments ranging from 86 to 105) and the seco nd se me s ter (e nrollment s rang ing from 47 to 76). For students who took the introductory course during the first of tho se years, the retention was higher at 46 % We will continue to compile retention data as they become available. We feel however that changes in overall retention are les s important than and may not be a good indicator for, the increased ability of first-year students to intelligently decide if chemical engineering is a good field for them (one of our main goals) In addition to providing an overview of chemical engi neering s tudent s felt that the introductory course helped prepare them for future courses, particularly the course on material and energy balances normally taken by so phomores. This opinion was consistent with that of the course instructor for the sophomore course, who observed that the students who had taken the introductory course were better prepared than previous students. The instructor also noted that the students had a significantly broader knowledge of the disci pline For example, when he mentioned to the students in the class that pha se equilibrium would be important in separa tion processe s s uch as di sti llation they recognized the pro cesses to which he was referring and appreciated the s ignifi cance of his statement. Although a quantitative evaluation is difficult other anec dotal information provide s positive feedback about the course. For example, two students who had recently completed the introductory course requested help from one of the authors to explore an issue in process control for use in a paper for a technical writing class. Specifically, they wanted to explore differences between feedback and feedforward control strat egies The students were in the first se mester of their third year a full year before they were sc heduled to take our senior-level process control class. Prior to the time we began teaching the introductory course, students at the same point in their education had little if any, concept of process conCh e mical Engineering Education

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trol. Yet, these st u dents had learned enough in the introductory course to de fine a question and pursue the topic fur theron their own. Incidentally, they were supplied with a process simulation pro gram (PICLES [ 2 1 ) and were able to use the program to address the issues of in terest. 70 ~---------, CONCLUSION 60 50 % of 40 Students 30 20 10 0-2 2-4 4-6 6-8 >8 Hours It has also been our perception that the co u rse has served to help build rela tionships between students. They appear to be working in groups and helping each other much more than they did pre viously. This interaction is facilitated by the group work required as part of Figure 2. Number of hours per w e ek spent outside of class on this cours e A new introductory course has been developed for first-year students inter ested in chemical engineering This two credit-hour one-semester course is de signed to provide a broad overview of the chemical engineering discipline and a foundation for other courses in the curriculum. Other objectives for the course include the introduction of fu n damental principles related to chemical engineering connection of material to the students experiences and fu ture coursework introduction of de sign concepts, and development of the class. Also, grading is structured so that students do not perceive that they are hurting their own grade by helping their classmates. Interaction between the faculty member teaching the course and the students has also been very positive In many cases this has resulted in continued interaction and discussions exchange of e-mail sharing of wedding announcements etc. long after the final exam is taken In order to provide the desired integrated overview, it wa s necessary to cover a broad variety of chemical engineering concepts. We were concerned that in doing this we might overwhelm the students with too much material. Like most schools our target for work outside of class (reading and homework problems) is two hours outside class per one hour inside. For a two-credit class (two hours per week in class) this translates to four hours per week outside of class. A recent polling of all our student s concerning the time they spend in class work outside of class indicated that the workload for the introductory course was on target at an average of approximately 3-4 hours a week. We conclude from this that the students have not been overwhelmed by the material presented in class Finally, the written material for the course has evolved considerably over the past four years but has now stabilized to a large extent. As mentioned previously, we have recently published a textbook l 11 for the course that is available for others who may be interested We end this section by noting that the course described in this paper has an appeal that extends to other situations where beginning students need to know about chemical en gineering. For example some colleges have a common fresh man engineering course, and the chemical engineering de partments do not see the students until the sophomore year. In those cases, the course described here could be given to first-semester sophomores prior to the traditional course on material and energy balances. It could also be used in two year colleges from which students may transfer into our programs. Winter 1998 student/faculty and student/student relationships. Student feedback although qualitative indicates that the course has been largely successful in accomplishing these ob jectives. The laying of a broad introductory foundation at the be ginning of a long academic program was of particular inter est and importance. Con s equently, the course was designed to establish the framework for the rest of the curriculum. Our intention was to facilitate learning by providing an overview and establishing connections so that in-depth material from upper-division courses could readily be integrated into an ex isting framework rather than waiting until a senior capstone course to attempt to tie things together. The approach also facilitates learning through repetition by providing a first-year exposure prior to the more-in-depth upper-division expos u re. We are providing thi s information so that other schools may con s ider this approach for adoption into their programs. Universities with no freshman engineering course may con sider adding a course like the one described here. Schools with an existing genera] freshman engineering course m i g h t consider replacing it with this course for students who are seriously considering chemical engineering as a major. Where this is not possible this course might be offered to sophomores in chemical engineering In addition two year colleges might use this course to prepare their stu dents for transferring to four-year chemical engineering programs. We are anxious to receive impressions and suggestions from others who have seen our course or book, or who have experience with similar attempts to prepare first-year stu dents for this discipline. REFERENCES 1. Solen, K.A. and J.N. Harb, Introduction to Chemical Pro cess Fundamentals and Design, McGraw-Hill, New York, NY ( 1997 ) 2 Cooper D J ., PICLES ( Proc e ss Identification and Control Loop Explor e r S ys t e m ), Version 4.1 Department of Chemi cal Engineering University of Connecticut ( 1995 ) 0 57

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.,~. 111 5 1111111 3.._c_u_rr_,_ c_u_l_u_m _________ ) FRESHMAN DESIGN PROJECTS In the Environmental Health and Safety Department RONALD J. WILLE Y, JOHN M. PRI CE Northeastern University Bos ton, MA 02115 F reshmen usually co m e to us w ith o ut an engi n eering background. They are accustomed to working a lon e o n sma ll well-structured problems do not under stand the l aws of thermodynamics an d h ave little concep tion abou t co n serva t io n of momentum e n ergy and mass Consequently we h ave b een re lu ctant to give ope ne nded design problems to them in spite of the fact that the fun of engi n eering is working o n real problems and fin din g sol u tions to them It s eems too big of a risk. While incorporating engineering h ealth and s afety iss u e s into the engineer in g curric ulum is desirable and h as b een ad dr es s ed by A BET ,l' 1 me eting this major cha ll enge is diffi cult given the many other ABET requirements Past papers that address possible approaches inc lud e the work of Gute, et a l } 21 Bethea 1 and Rossignol et al.f 4 1 Our approac h intro duces students t o ope ne nd ed problems early in the curricu lum. We find that their creative abilities provide fresh so lu tion s t o mundane problems. FRESHMAN CURRICULUM Northeastern University has a five-year cooperative edu cation program in e n gineering The freshman year ha s three Ronald Willey holds BSc and PhD degrees in c hem ical engineering from the Uni versity of Ne w H ampshire and the University of Massachusetts (A mherst ) respectively. H e h as six years of in dustrial experience in the paper ind u stry and has been a t Northeas tern Un ive rsit y si n ce 1983. H is te aching responsibilities incl ude the Unit Op erations laboratory. John M Price is Director of En vironmenta l H ealth and Safety at N ortheastern Un iversity. After re ceiving a BS a nd MS in chemical engineering from Northeastern he earned an MS in environ mental sciences from H arvard University H e has fifteen years experience implementing and man aging occupational and e nvi ro nment a l safe t y pro grams at academic researc h institutions While incorporating engineering health and safety issues ... is desirable and has been addressed b y ABET,w meeting this major challenge is difficult. .. Our approach introduces students to open-ended problems early in the curriculum ... their creative abilities provide fresh solutions to mundane problems. quarters a nd upperclassmen take two quarters of classes and of cooperative education during each of the next fo ur years. The resu lt is eleven quarters of classroom training and s even or eig ht quarters of indu strial experie n ce. To allow freshme n the opport unit y to meet College of Engineering (C OE ) fac ult y early in their academic career COE fac ult y take an active ro l e with fres hman engineering st udent s. Engineeri n g cour s e s offered in the fres hm an year are C-pr og rammin g durin g th e f all Probl e m sol v in g u s in g s pr ea d s h ee t s and MathCad in th e wint e r Engin ee ring d e si g n in th e sprin g The e n gineering design course is divided into ten sections wit h abo ut thirt y st ud ents in eac h section. The sections meet for 65 minutes three times a week. Our quarter system al lows for just under e le ven week s of classroom meeting s eac h qu ar te r. Sections are divided by intended major and assig n ed to faculty from the appropriate departments. Thi s paper i s devoted to declared chemical e n gineering majors Engineeri n g design uses a textbook developed by Northeastern 's Gerald Voland, En g in ee ring b y D e sign cs i He breaks down th e design process into key s t ages that inc lud e 1 ) N ee ds d e t e rmination 2) D e si g n goals and sp ec ifi ca tion s 3) Abstra c tion 4) E v aluati o n of a lt e rn a ti ve d e si g n s 5 ) Er g onomi c anal y sis In general, engineeri n g design students are assigned a minor Co p y r ig h t ChE D iv i sion of AS EE 1 998 58 Ch e mi c al Engin ee ring Education

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TABLE 1 Proposal Outline for Student Project Design S ubmittal GEi 1 03 Spring 1 996 Minor Design Project Due April 23 1996 "If there isn't a need why bother? R.J. Willey 4/5/96 Summary: Excellent designs begin w ith a proper needs assessment and the correct statement of the prob l ems to be so l ved. An excellent example of posing the proper questions before solving the problem at hand is space craf t reentry. Your gro up is to prepare a 5-page proposal (doub l e spaced a nd 12-point Courier font) and a 5-min ut e presentation about your major design project. This work will be due on April 23, 1996. Mr. Jack Pric e will r eview and assign grades on your oral presentations (25 % of the total minor design project grade) Eac h group must go to the front of the classroom After a brief introduction from each group member, o n e of yo ur gro up members should serve as a spokesperson That person should briefly define the need, the problem to be so l ved and the methods to be used. Proposal Outline Objectives Us in g a numb ered list, sta t e your objectives. Be as precise as possible. Background Who will be served by your solution/design? Where will your solution/design be used ? What is the past hi sto r y related to the problem? Are there any important references re l ated to the problem that you are working on? Existing solutions and prior work on the problem should be described. Methodology Focus on what t echniques you will use to help you solve the problems and succeed with a successful design. Use Prof. Voland s a nd class notes to obtain methods on how to proceed. Proposed Schedule Includ e a proposed schedule that is simi l ar to the schedule shown in Figure 2.6 page 88. Use weeks as the time period and adjust phases to match your problem/design. Person Loading Chart Include a person l oadi n g (Gantt) c h art like the one shown in Figure 2.7 Use hours as the time period and adjust the task list to match your problem/design requirement. Autocad Drawing In c lud e a schematic or layout drawing for the project that yo u are working on. Expected Results Begin with th e end in mind. What are the deliverables "? Who wi ll benefit ? Costs What will be the costs involved? "Personpower" can be estimated at a direct cost of $45.00/hr. Other costs w ill in volve materials and supp li es to bring about the solution/design (not the cost of the final recommended design). TABLE2 Major Design Projects, Spring 1996 # Department I. Mail Services 2. Mail Services 3 Physical Plant Location Basement Contact J. Devine Basement, Columbus Pl. J. Devine Mail room Columbus Pl. J. Devine Project Description Workstation lighting evaluation Noise level survey for letter-stamping machine Employee fall protection from loading docks 4. Physical Plant Various B. Mitcheson Loading-dock assesment 5. Environment Health Various l abora t or i es 6. E nvironm ent Health Various dark rooms 7. Environment H ea lth Various comp ut er labs 8. Environment H ea lth Various l aborator i es 9. Environment Health Various l aboratories 10. Chemical Engineering 8 Mu gar Winter 1998 S. Brehio S. Brehio J. Price S. Brehio S. Brehio A. Bina Quality contro l check on safety show ers and eye-wash station survey Evaluation of si l ver recovery options for env i ronmenta l compliance Ergonomic eva luation of comp ut er workstations Opportunities for waste minimization in the generation of HPLC solvent waste Strategies, fac ilit y requirements and costs for a centra l organic so lv ent bulk ing facility De sig n of fl ow measurement experi ment and a major design project, eac h to be completed u si ng the method s pre sented in Vo land 's text. In the c hemical engineering section, these minor a nd major projects address the same problem Our minor de sig n project (see Table 1 ) consists of a need s assessment and proposed approach to one of the major design projects listed in Table 2. The ma jor design project i s execution of the actual work proposed. Students are divided into groups of three at the second class meet ing, pro vi ding a total of ten teams. Each team se lect s a project from Table 2-no duplication is allowed. Each team 's interests are matched to a project. Each project assigned to a team ha s a University administrator who serves as the "cl ient. The st udent teams serve as consulting engineer ing services Additionally, our Of fice of Environmental Health and Safety ( OEHS ) serves as a mentor and an interface between the clients and the consultants. As Table 2 s how s, design projects vary from noise surveys in the Uni versity mail room to the optimiza tion of hazardous waste disposal. The project s introduce s tudents to s ur vey in str ument s, to data evalua tion to re g ulator y compliance is s ue s, and in vo lve interaction with a var i ety of people. Students begin learning engineering principles (e .g. ve locity mea s urements involving Bernoulli 's equation), team s kills communication skills (written and oral), and economics. With a little investment and so me oversight by the OEHS the University benefits from the students' project recom mendations ( discussed in more de tail below ) The minor and major assignments, the proposal and the design solu tion comprise 55% of the course grade. The remaining portion is based on two examinations (30%) and daily homework assignments 59

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(15 % ). AutoCad is also presented in this class (about one third of the lectures) and students are encouraged to make drawings of their major assignment using it. As with any open-ended term project, students tend to put off work until the last minute, with the usual disastrous results To avoid this out come, students are required to submit a weekly log book and are given small assignments that push them 1) to get their groups together 2) to begin meeting with their contacts 3) to obtain background information, and 4) to work towards a solution. The logbook system also serves to identify early such problems as an inability to connect with the University contact or the exist ence of a nonparticipating member For the instructor the project process is simi lar to managing a small consulting firm made up of all rookie teams The s tudent s generally find their contacts during the fir s t week and will begin the literature check s, but then their meth ods diverge. One year, two s eniors were inten tionally recruited to work with two freshman team members With the advantage of the se niors co-op and military experience the teams attacked their project with vigor. Both design so lutions-the redesign of a loading-dock area and the creation of a safety check list (see Table are now being implemented by the Univer s ity. Eight of the ten groups functioned well. Their final de s igns were quite good They s ucceeded in part because they were s elfs electing and they shared a general interest in working on a real problem On the other hand, one of the eight all-fresh man teams was not successful. No previous en gineering work experience or effective leader ship existed within the group. One s tudent made his initial contact with the client regarding the design of a flow measurement system for two centrifugal pumps. He quickly a ss e s sed the situ ation claimed the solution was easy and stated that he should be done after just a few hours of work He never included the other team mem bers in the plans or their execution and they, in turn never tried to participate expecting this student to carry them through. Other all-freshman team s turned in good-to excellent reports. One team worked the mail room workstation lighting problem A s part of their pre s entation they built a 3-D model of the room. The model ceiling had holes cut out at the 60 P11t s TABLE3 Loading Dock Safety Checklist Generated by Students Who Worked on Project#3 General Area 3 _yes n o Ar e l oa din g po s iti o n s fo r tru c k s m a rk e d w ith lin es? 3 _yes n o Ar e dock g u ar d s in o p era bl e c onditi o n ? _yes n o Ar e l o adin g areas fr ee o f p o th o l es? _yes n o Ar e fl oo r s cle an e d d a il y? _yes _n o A r e tr as h co nt a in e r s e mpti e d d ai l y? 2 _yes n o A r e trail e r w h ee l c h ocks pr ovi d e d fo r eac h t ru ck? 1 _yes n o Ar e trailer w he e l c h oc k s c hain e d t o th e buildin g? 3 yes n o Ar e prop e r w arnin g s i g n s cl e arl y v i s ibl e for ge n e ral s afet y i ss u es? 3 _yes _n o I s ventilation adequ a te ? 3 _y e s _n o I s lighting a dequat e? 3 _yes n o D o e s th e do c k ha ve a roo f? 2 _y e s n o D o e s ro o f of dock h ave a drain age s y s t e m ( i e. g utt e r s)? 3 _y e s n o l s d o ck within hei g ht acco rdan ce of a ll tru c k s th a t w ill u se th e d ock? 3 _yes n o A r e prop e r s i g n s p os t e d in s tru c tin g driv e r s t o turn o ff th e ir e n g in es? 3 _yes n o A r e fi r s t -a id kit s r ea dil y avai l a bl e? 3 _yes n o Ar e e m e r ge n cy t e l e ph o n es eas il y access ibl e? 3 _yes n o A r e fi r e ex tin g ui s h e r s/s prinkl e r sys t e m s in wo rkin g o rd e r and accessi bl e? 2 _y e s n o I s n o i se l eve l of d oc k in acco rd a n ce w ith fe d era l r eg ul a ti o n s? 2 _yes n o I s d oc k e quipped with h a nd ra il ? 2 _yes _n o I s d oc k marked with v i v id p a int t o di s pl ay h azar d o u s ar eas? 3 _yes n o Ar e e m e r g en c y exit s pro vi d e d m a rk e d a nd k e pt cl e a r ? 1 _y e s n o Ar e fo o t rail s in pl a c e a t th e e d ge o f th e d oc k ? 3 _ye s _n o Are mirror s pro v ided for blind s p o t s"? 2 _yes n o Ar e s t o ra ge ar ea s of e quipm e nt, p a ll ets, m ac hin e r y marked and k e pt cl ea n ? 1 _yes n o Ar e a re as fo r dri ve r s provid e d durin g l oa din g and unl oa din g? 2 _yes n o Ar e ped es tri an w a l k w ays cl ear l y id e ntifi e d ? 2 _yes n o Ar e inclin e of ramp s u se d fo r h a nd l oad in g/ unl oa din g n o t too s t ee p ? 3 _yes_ n o 2 _yes_ n o 2 _yes n o 3 yes _n o 3 yes n o 2 _yes _n o 3 _y e s n o .5 _yes_ n o .5 _yes_ n o .5 _yes_ n o .5 _yes n o .5 _yes _n o .5 _yes_ n o 3 _yes n o Trai11i11g a11d Perso1111el l s sa fet y a nd health tr ai nin g pro v id e d t o d oc k p e r so nn e l ? Ar e e mpl oye e s te s t e d o r ev aluat e d o n th e ir kn o wl e d ge o f saf e ty pr oce dur es? Ar e r e fr es her c our ses in safe t y a nd h az ard pre v enti o n pro v ided t o wo rk e r s? Ar e do c k per s onn e l train e d in th e u se o f bridge pl a te s o r d oc k l eve l e r s? Ar e dock p e r s onnel train e d in th e prop e r c ar e of h e avy p ac ka g e s? Ar e v isitor s g iven prote c tiv e wea r a n d ar ea away fr o m do c k to co n g r ega t e? Ar e dock p e r s onnel famili a r with u s in g a manu a l and motori z ed equipm e nt ? Ar e d oc k p e r so nn e l p rov id e d w ith safe t y e quipm e nt ( i f a pplicabl e) H a rd hat s W e i g ht b e lt s Glo ves E ye prot ec tion Ear prote c ti o n Footwear A r e do c k wo rker s tr a in e d t o sec ur e l oa d s fo r tran s p o rt ? Th e ab ove c h ec kli s t is ba sed 0 11 a ra11 k in g sys t e m of J t o 3 po int s p e r qu es ti o n A (3) i s dee m e d c riti c al a (2) i s d ee m e d imp o rt a nt w hil e a ( I ) is d ee m e d o pti o n a l. To find yo ur t o t a l p oss ibl e sco r e a dd th e p oss ibl e p o int s co lumn di s r ega r d in g th ose q u es ti o n s that a r e nonappli c abl e. F o r eac h qu es ti o n a n swe r e d "yes," g i ve yo ur self th e p o int a m o u11t g i ve n t o that qu es ti o n F o r e a c h qu es ti on an swe r ed 11 0," a dd 11 0 p o int s. A dd a ll yo ur sco r ed p o int s. Thi s w ill g i ve yo u yo ur t o t al ra w sco r e. Now r ev i ew yo ur t o t a l r aw score a nd m ake su r e i t co mpli es w ith th e fo ll ow in g: All th e qu es ti o n s g i ve n a r a nk o f(]) a r e a n swe r e d "yes." A t l eas t 80 % of t h e qu es ti o n s g i ve n a r a n k of (2) a r e a n swe r ed "yes." Qu est i o ns w ith a rankin g of ( I ) ar e l eft t o th e di sc r e t io n of th e p ro p e r m a na ge m e nt ff th ese co mpli a n ces h ave b ee n m e t th e n yo u r d oc k i s in acco rd a n ce w ith th e s a fety m eas ur es we r e quir e. If thi s i s n o t so th e n a dju s tm e nt s a n d m o difi ca ti o n s mu s t b e mad e until th e r e quir e m e nt s a r e m e t. Ch e mi c al En g in ee r i ng Edu c ation

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existing lighting-fixture locations and using a simple flashlight shining from above the students were able to dem onstrate the inefficiencies of the light ing grid They then demonstrated how the placement of two additional light ing fixtures over the proper work area could correct the lighting. By ex changing the top of the 3-D model with the properly modified ceiling and shining the light through it they were able to present their solution efficiently and observably. consisted of a summary of the design solution. Several models iconic (resembling the situation but not having the functionality) and analogic (not resembling the situation but having the functionality) were made by the groups as the projects progressed. Figure 1 shows one example of student creativity The model shower pictured was made to help explain design requirements for American With Disabilities ACT com pliance concern s Another group built a scale model of a process to recover silver generated in the University s photo labs. This model was constructed so that each major functional component could be removed. T h e st u dents used the model during their presen tation to help the class understand the func tionality of their proposed silver-recovery system The presentation was extremely rewarding for the class and the instructor. CONCLUSIONS Since students have generally been conditioned to work individually prior to entering college, one of our big gest cha ll enges was getting them to work together. While team work is a novelty in the academic environment, when these students take on their fir s t industrial co-op assignment team work is often the expected mode of operation An important feature of our approach is to develop team working skills. Another related challenge was the division of work While eight of the ten student teams handled the diviFig u re 1 Stud e nt holding an iconic model made for Project #5 related to safety showers Open-ended, real problems are challeng ing to make work in the classroom. There is no instructor s solution manual availsion of work quite well in one team there was one student overly concerned about the grade and another more con cerned about what he was "really learning. These two never reached a consensus about what the professor wanted and ended up giving individual solutions Meanwhile, the group s third member watched in bewilderment while the other two argued constantly during team meetings. Another poorly functioning group had a clear cultural divergence that Jed to little or no team effort. This group was not self-selecting, having been formed of late registrants who came to class for the first time on the second day. The members were from different countries and did not know each other previously This team did not work well to gether primarily because one team member worked on the problem by himself and didn t include the other two members who, in this case, were satisfied that someone else was goi n g to do the work We required two group reports and two presentations dur ing the quarter. The first report was the proposal for the "client s approval" and was due about midway into the quar ter. The corresponding presentations were limited to five minutes per group and were given on the day the propos als were due. The second, formal report described the final design solution intended to meet the client's needs The second presentations were twenty minutes each and Winter 1998 able and each project is demanding, re quiring constant attention by the instructor. Project paths can change as the quarter progresses. Common difficult situations center around a contact not responding or a group member not participating. Sometimes, design prob lems are too vague. We encourage others to contact their Environmental Health and Safety departments to discuss a similar approach at their University Not only will their students learn to alleviate persistent campus hazards, their school just might gain some inexpensive physical improvement s. REFERENCES 1. ABET Criteria for A cc r e diting Programs in Engin e ering in the United Stat e s, Engineering Accreditation Commission, Accreditation Board for Engineering and Technology Inc. New York NY ( Sections IV.C.2 and IV.C 3 ) ( 1994 ) 2. Gute D M A.M. Rossignol, N.B Hanes, and J.T Talty Factors Affecting the Performance of Occupational Health and Safety Topics in Engineering Courses," J Eng. Ed., p. 163, July ( 1993 ) 3 Bethea, R.M., "Engineers Encourage Universities to Em phasize Safety in Curriculum ," 0cc Health & Safety p. 22 June ( 1992) 4 Rossignol A.M ., and N.B. Hanes Introducing Occupational Safety and Health Material into Engineering Courses, Eng. Ed. p 430 April (1990 ) 5 Voland, G M Engineering by Design Addison Wesley Puhl. Co., Reading, MA ( 1998 ) 0 61

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[9i5=i curriculum ) ... _1111111_.__ -----INNOVATIVE WAYS OF TEACHING POLYMERIZATION REACTION ENGINEERING Ex ch anging Information Between the University and Industry JoAo B P. SoARES, ALEXANDER PENLIDIS, ARcHrn E. HAMrnLEC* University of Waterloo Waterloo, Ontario, Canada N2L 3Gl T he polymer industry is one of the most important and fastest growing segments of the chemical industry today and this growth has created a high demand for profes sio nals with adequate knowledge to attend to its very special needs. Besides the classical core subjects of the chemical engineering curriculum, knowledge of several ad ditional topics is required for the student who intends to apply for a position in the polymer manufacturing industry The technology for polymer manufacture is in a constant state of change, and any undergrad u ate or graduate program that relies only on established approaches in polymer chem istry and physics will quickly find itself out of date In this article we will describe how our interaction with several polymer manufacturing companies through industrial short courses and research projects has led to the development of a dynamic and u p-to-date undergraduate and graduate curricu lu m in po l ymer science and engineering technology. The technology for polymer production is a very dynamic fie l d due to the hig h demand for polymeric materials wit h entirely novel or improved properties New discoveries and applications in po l ymerization catalysts and initiators, in polymer reaction engineering, po l ymer characterization and polymer processing freq u ently redefine the boundaries of Joiio B P. Soares received his BEng (1983) from Federal University of Ba h ia Brazi l his MSc ( 1 985) from State Univers i ty of Campinas, Brazil a n d his PhD (1994) from McMaster University all in chemical engineer ing His main research interests are in the fields of metallocene and Z i eg l erN a/ta polymerization. Alexander Penlidis received h is Dip/ Eng (1980) from the Universi t y of T hessaloniki Greece and his PhD (1986) from McMaster University both in chemical e n gineering His interests lie in the areas of polymer reactor modeling design optimization, and computer control. Arch i e E Hamielec joined the chemical engineering department at McMaster University in 1963 took early retirement in 1993 and is cur rent l y a P rofessor E m eritus H e is actively engaged in consu lt ing for the po l ymer manufacturing industry McMaster University, Hamilton Ontario, Canada LBS 4L7 62 k n ow l edge in polymer science and tec h nology. As a resu l t, several of the leading technologies for polymer manufacture are co n stant l y being modified to meet new market demands Although it is stimu l ating for those involved in the field, this dynamic pace nonetheless creates a significant concern for instructors teaching polymer-related courses in academia since i t req u ires that both unde rg raduate a n d graduate courses be regularly updated to reflect these new developments Keeping up to date with the scientific literature alone, even TA B LE 1 Par ti a l List of S ci e ntifi c J o urn a l s in Poly m er Scie n ce an d E n gineering [oumal Name (Periodicity) Publisher European Pol y m er Journal ( Mont h l y) Per ga mon Pre ss Int ernat ional Pol y m e r Science and Tech. ( Monthly ) RAPRA Journal of Applied Pol y m er Science ( Quarterly ) John Wi l ey & Sons J ourna l of Ma cro m o l ecu lar Science (Month l y) Marc e l Dekker J ou rnal of P o l ymer Engineering (Q uarterly ) Freund Pub Hou se J of Pol yme r Sci.: Poly. Chem. (Mo nth/Semi-Month ) Wi l ey & Sons J of Polymer S c i.: Pol y Ph y. (Month/Semi-Month) Wiley & Sons Ma cromo l ecules ( Bi-Weekl y) American Chem. Soc. Ma c r omo l ec ular R eports (8 per Year) Marc e l Dekker Ma cromo l ec ular Symposium ( Irregular) Hiithig & W epf Verlag P o l y m e r ( Bi-Weekly ) Elsevier P o l y m er Bull eti n ( Bi-Monthl y) Springer Pol y mer Engineering and Science (Semi-Monthly) Soc of Poly. Eng. P o l yme r I nternational (Monthly) John Wile y & Sons Pol ymer J o urnal ( Monthly ) Soc of Poly. Sci., Japan Polymer R eac ti on Engineering J ourna l ( Quart e rly ) Marcel Dekker Progress in P o l yme r Science (B i-Monthly ) P e rgamon Press Tr ends in Pol yme r Science (Mo nthly ) Elsevier Copyright ChE Di vision of ASEE 199 8 Chemical Engin ee ring Education

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in a relatively narrow branch of polymer s cience and engineering, can be a time-consuming task due to the numerous scientific journal s available in the field s ome of which are listed in Table 1 The polym er scie n ce and eng in eering theme illus trates remarkably well the old s aying that in order to teach a subject well one mu s t be activel y in v olved in research in that subject. That i s the only way one can stay curre nt with all the new development s and main tain a sense of co h erence and relevance in the face of the immense body of information available to academ ics nowadays An additional and equally important point to remem ber when de signing an academic course e s pecially at the undergraduat e le ve l is that equal importance must be give n to b oth s cientific-relevant topic s and those that are of immediate concern to industry s ince mo s t students will be seeking indu s trial job s after gradua tion R esu lt s from recent survey s on employment in the United States a nd Europe indi cate that as many a s 70 % of che mical engineering graduate s will have worked with a polymer-related industry at some point in their profe s s ional career. Unfortunately the importance of polymer co ur ses for chemical engineers at the undergraduate level is sti ll overlooked in several academic institution s. In this article we will describe our instructional ef forts in polymer science and technolog y at three di s tinct levels: industrial-intensive short cour s e s, academic courses and final-u nd ergraduate-year de s ign and re searc h projects. We will s h ow how these activitie s comp l ement each other l eading to univer s ity courses with a hi gh content of industrially relevant material and to industrial course s that bring recent academic advances in polymer science a nd engineering to in du stria l applications. INDUSTRIAL SHORT COURSES We offer three courses annually in Canada the United States, a nd Europe Although the details of these courses might vary according to the type of audience they are intended for they combine a very s trong component in fundamental und erstanding of polymerization reaction engineering with recent adva n ces in several aspects of polymerization processes. In addition to the regular lecturer s, invited speakers (mainly from industry but also from academia) are regularly asked to give twoto fo ur-h our lectures. It has been our experi e n ce that the material covered by the invited s peak ers is highl y relevant to our indu s trial short courses and can b e s ucc essfu ll y used to complement the content of o ur uni versity courses Table 2 s ho ws the sy llabu s of a recent industrial intensive s hort course in polymerization chemistry and Winter 1998 Sessions Chain-Growth P o l y m e ri za ti o n M ec h an i s m s a nd Kin e ti cs Ad va n ce d P o l y m e ri z ati o n Kin e ti cs 2 Emul s ion Di s p e r s i o n a nd Su s p e n s i o n P rocesses P o l yo l efi ni c Proc esses TABLE2 Syllab u s of Industrial Short Co ur se Topic s Line a r bran c hed a nd c ro ss linked c h a in s via fr e e-radic a l p o l y m e ri za ti o n Lin ear a nd bran c h e d c h a in s v ia i o ni c m ec h a ni s m s ( Zieg l e rNa n a an d M e t a ll oce n es) St oc km aye r s bi var i ate di s tr i buti o n in s t a nt a n e ou s prop e rty m e th o d s ld e ntifi ca ti o n of multipl e ac ti v e s it e t y p es ( GPC TREF NMR ) Id e ntifi ca ti o n of act i ve s it e p e rf o rm a n ce L o n g c h a in bran c hin g Z i eg l e r a tt a and m e t a ll oce n e c at a l ys i s St y r e nic s, PVC Bat c h s emi bat c h a nd c ontinuou s o p e ration Th e nn o d y n a mi cs an d s ur face c h e mi s tr y P arti cl e nu cle ati o n a nd grow th I o ni c a nd s t e ri c s t a bili za ti o n P art i cle s i ze di s tributi o n a nd m o l ec ul a r we i g ht di s trib. M o l ec ul ar, rh eo l og i ca l a nd so lid -s t a t e p ro p e rti es ( LOP E HOPE LLDPE PP impa c t c opol y m e r s) E ffec t o f s h o rt a nd l o n g c h a in bran c hin g a nd mol e cul a r we i g ht di s tributi o n s E ffec t s of m a in p rocess va ri a bl es o n p ro du c ti v ity a nd p o l y m e r properti es M o d e l s of p o l yo l e fin p ro ducti o n p rocesses a nd pl a nt d a t a co mpari s on s 3 Prin c ipl es o f Bat c h se mi bat c h a nd co ntinuou s o p era ti o n P o l y m e r R eac t or D y n am i c m o d e lin g of reac t o r sys t e m s M o d e lin g a nd P o pul a ti o n bal a n ce e qu a ti o n s fo r p a rticl e s i ze a nd m o l ec ul ar Kin e ti c D ata we i g ht C o ll ec ti o n S c r ee nin g a nd fac t o ri a l d es i g n s for d a t a co ll ec tion 4 M o d e rn Spe c i a l T o pi cs Rubb e r M a nu fac turin g P rocesses and P ro du c t C har ac t e riz a tion 5 M o nit o rin g D y n a mi cs, a nd C o ntr o l o f P o l y m e riz a ti o n R ea ct o rs Se qu e nti a l an d n o n lin ea r d es i g n of ex p e rim e nt s Ev o lution a r y o p e rati o n M o d e l di sc rimin a ti o n i ss u es Bulk so luti o n a nd e mul s i o n t e rp o l y m e ri za ti o n s R eac ti v it y rati o es tim a ti o n M o nt e Car l o m e th o d o l ogy a nd a ppli ca ti o n s R eac ti v it y rati o es tim a ti o n Optim a l se n s or se l ec ti o n R eac ti ve pro cess in g Prin c ipl es of t e mp era tur e ri s in g e luti o n frac ti o n a ti o n ( TREF ) M e a s ur e m e nt of l o n g c h ai n bran c hin g ( GPCNTSC/LALLS ) C h e mi c al m o di fica ti o n o f p o l y m e r s Cr ys t a lliz a ti o n Anal ys i s Fra c tion a tion ( CRYSTAF ) D e finition s of rubb e r s and e l as tom e r s S y nth es i s an d produ c ti o n o f rubb e r s R ece nt d eve lopm e nt s in EP(D ) M a nd p o l y a o lefin s: m eta ll oce n e ca t a l ys i s/gas ph as e proc ess / s in g l e s it e vs multi -s it e ca tal ys t s Mol ec ular s tructur e a nd ph y sical prop e rti es Compounding vulc a ni z ation and application s O ve r v i ew o f curr e nt co ntr o l p rac ti ces S e n o r s for monit o rin g r e a c tor b e h av i o r E n e r gy b a l a nce a nd ra t e co ntrol C o ntr o l of produ c t p ro p e rti es Mod e l u se to combin e o n-line and off lin e d a ta K a lman filterin g a nd inf e rential c ontrol Software se n s or s a nd multi v ariabl e s tati s ti cs Optim a l r e actor g rad e c h a n ges Ad v anced lin ear and nonlinear control 63

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re ac tion engineering, with emphasis on metallocene catalysts, emulsion a nd s u s pen s ion polymerization proce sses. As can be see n the fir st thr ee sess ions concentrate on fundam e ntal s and mathematical modeling of coordination and free-radical polym er ization. Thi s forms the basi s for und ersta ndin g of the more applied topics cov ered in s ub se quent sess ion s. Propertie s of polyolefin re s in s and rubber s, es pecially s tructure-property relation s hips, are given s pecial attention Recent a d va n ces on re actor monitorin g, dynamic s, and control, as well as kinetic data collection and a naly sis, are a l so covered in depth. A sess ion on modern s pecial topic s is ge nerally offered to cover new technologies and research topic s in pol y mer sc ience and engineering Mod ern polymer c haracterization technique s are gen erally covered in the last session, although they are di sc u sse d at every available opportunity dur ing the previou s sess ion s, includin g applications of on-line sensors. A s mentioned before, invited s peaker s make an important contribution to this in s tructional effort. Table 3 li s ts the name s, topic s, and affiliations of some of the invited s peakers who ha ve partici pated in our courses in the past five years. In-hou se short courses are also offered to meet the need s of s pecific companies. These in-house courses ma y range from one to five day s. They can be as ge neral as the course d escr ibed in Table 2 or focused on the technologie s of th e s pecific company. Po ss ibilitie s also include combinations of s pecial topics : for example, a two-day update on the u se of statistical method s and the design of experiments for polymerization proce sses. Table 4 shows the sy llabu s of s uch a co ur se on polymer reaction engineering of polyolefinic proce sses re cently given in the United State s. This particular course concentrated on the m a nufacture of polyolefin s, with s pecial emphasis on new tech nolo gies for metalloc e ne catalysts. It ha s b ee n our experience that the se courses are mutually benefici a l for the indu s trial participant s and for the lecturer s. On one hand the industrial participant s have an opportunity to update their knowledge of modern advances in a broad area of polymer sc ience and technology, and over the years we have been glad to note that several in dustrial participants have initiated research col laboration s with the instructors after taking the courses and that s ome of the topic s introduced 64 TABLE3 Partial List of Invited Speakers, Their Topics, and Affiliations Dr. T.A. Due ve r Design of expe riment s fo r C h em. Eng. Department polymerization data co ll ectio n U ni ve r s it y of Waterloo Dr. G.N Foster C h aracter i za ti on a nd physical Un i on Carbide propertie s of polyolefins Bo und Brook NJ Dr. E K ontos Rubb er manufact urin g proce sses Uniroyal Chem. Co. Dir. Elastomer s and product c h arac t erizat i o n Nauga tu ck, CT Technology Dr. K. Malone Organi c peroxides for freeE l f Atoc h em. rad i ca l polymerization Buffalo, NY Dr. B Monrabal Crystallization analysis Polymer Character ., S.A. fractionation (C RYSTAF ) Patema Spai n Dr. G.L. R em p e l Metallocene cata l ysis a nd cataC h e m E n g. Department l y ti c m odificat i o n of p o lym e r s U ni ve r s it y of Waterloo Dr. C. T zoga naki s Pol y m er processing and r eactive Chem. E n g. Department extrusion Univers i ty of Waterloo TABLE4 Syllabus: In-House Short Course for Polyoletin Production and Characterization Intr od u c ti o n Polymerization Processes B as i c Mathematical Modeling Techniques Adva n ced Mathematical Modeling of P o l y m erizat i on Proc esses Ca t a l y ti c Site Type Id entifica ti on R eac t o r D y n a mi cs /Control/Grade Transitions So lubl e vs. heterogeneous ca t alysts Polymerization m ec h a ni sms: homovs. co p o l ymer i za ti on/li n ear vs. b ranc h e d c h a in formation Co nt ro l of stereoreg ul ar it y, mole c ul ar we i g ht s h or t a nd l o n g c hain branching Effect of polymer microstucture on mechanical and rheo l ogica l propertie s Gas ph ase/s lurr y bulk m o n omer and diluent/solution Fluidized bed vs. st irr ed bed gas-p h ase reactors Loop r eac t ors vs. s tirr ed-bed s lu rry reactors Processes for manu facture of high-impact copo l ymers Vis -br eaki n g processes Mass balances: batch sem i-b atch, a nd co ntinu ous opera ti on of CSTRs and CS TR trains Energy balance Polymerization kinetic s P opu l ation balances Instantaneou s properties methods vs. method of moment s Multiplicity of ac ti ve s it es Heat a nd ma ss transfer limit atio n s Particl e s i ze distribution Deconvolution of GPC c ur ves u s ing Flory's mo st probab l e distribution Deconvolution of TREF curves using S t ockmayer' s d i strib uti on G P C/LC-transform-a new approac h to site identification C RYST AF a nd C ITREF Overview of c urr e nt contro l practice s Sensors for monitoring reactor behavior Ene r gy balance an d rate contro l Control of prod u c t propertie s Model u se to co mbin e o n lin e and offline d ata Kalman filtering a nd inf e r e nti a l con trol Software se n so r s an d multi va ri a bl e s tati st ic s Optim a l r eactor grade c h a n ges Advanced linear and n o nlin ear co nt ro l Chemical Engin ee rin g Edu c ation

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The technology for polymer manufacture is in a constant state of change, and any undergraduate or graduate program that relies onl y on established approaches in polymer chemistry and physics will quickly find itself out of date. In this article we will describe how our interaction with several polymer manufacturing companies ... has led to the development of a dynamic and up-to-date undergraduate and graduate curriculum in polymer science and engineering technology. TABLES Syllabus for Pol ymer Reaction Engineering Course Week Topics Overall co ur se objectives Basic concepts and definitions in polymer science 2 Definition of m o l ec ular weig ht averages and distributions Method of moments Ana l y ti ca l te ch niqu es fo r m eas urin g molecular weights 3 Step grow th polymerization Co nd e n satio n vs. addition po l y m ers Statistical treatment of ste p -grow th p o l y m erization Equal reactivity ass umpti o n (ERA) Irr eve r s ibl e grow th w ith ERA Carothers eq u ation Flory-Shultz distribution Determination of ki n e tic co n s t a nt s 4 Stoichiometry of lin ear systems Generalized Carothers eq u ation Deterministic treatment of s t ep growt h p o l ymer i zat i on Modebng s t ep-growt h polymerization w ith o ut ERA Effect of monofunctional age nt s R evers ibilit y a nd int e r c h a n ge reactions 5 Free-radical h o m oa nd co p o l ymer i zat i on Initi atio n propagation, a nd termination B as i c h y poth eses Commercial initiators Initi atio n rate I sot h er m a l opera ti o n initiat or effic i e n cy Prop agatio n c h aracteristics 6 Chain co nform atio n s Tacticity Termination c h aracterist i cs C h oice a nd amo unt of initiat o r Inhibiti o n a nd retardation Impuriti es Development of equations for polymerization p ro ducti o n rate H o m opo l y m erization in batch reactors D ead-e nd polymerization 7 Derivation of the instanta n eo u s copo l ymer composition (ICC) equation Plots of the ICC e qu a ti o n Rea ctiv it y ratios In troduction to compos iti o n contro l m e th ods Meyer-Lowry equat i on C umul a ti ve co p o l ymer compos iti o n D epro p agation Molecular weigh t (MW) development fo r linear h omopo l ymers Mid-Term Exam 8 MW de ve lopm e nt: averages a nd di s tributi ons Pra ctical hint s o n MW co ntr o l a nd t e mp erat ur e programming Energy balances Temperature a nd co ntroll e r design Modes of t erm in at i o n R eactio n s with c h ain transfer agent Chain transfer to m o n o m e r MW development: branched h omopo l ymers 9 Transfer t o polymer T e rmin a l d o ubl e-bo nd and internal double-bond r eac ti ons B ackb itin g Indu st ri a l examp l es Method of moment for branched systems MW d eve l o pm ent fo r l inear a nd branched copo l ymers Effect o n glass tra n s iti on temp era ture Bimolecular t e rminati o n kin e ti cs 10 Emulsion p o l y m e ri za ti o n: co n tras t with other polymerization m et h ods Nucleation and grow th Th er m o d y n a mi cs Free-radical co nc e ntrati o n Emulsion p o l ymeriza tion kinetics: h o m oa nd co p o l y m e ri za ti o n 11 Lat ex particl es s i ze P o l y m e r m o l ec ular weight Effects of pH a nd i o ni c stre n gt h Impurities Coagula ti on Multiple pha se l a t ex parti c l es Intr o du ction t o math e m a tical a nd co mputer m o delin g 1 2 Ioni c (a nioni c a nd ca tioni c) a nd coordi n a ti o n (Z ie g l e r -Na tt a a nd m e t a ll oce n e) p o l y m e ri za ti o n s Bri ef ove r v i ew Mechanisms Pol yme r properties 1 3 R eview Sampl e problems a nd genera l discussion o n the design of l arge polymer i za tion reactor s Final Exam Wint e r 1998 during the courses have found practical appli cations in indu s try. On the other hand the in str uctor s benefit greatly from the se interactions s ince the contacts permit them to s tay in tune with the current need s of indu s try and with recent a d v ance s of a practical nature that very often are not di s closed in the sc ientific litera ture. Thi s i s not only a good way of influencing the direction of so me of our applied re se arch, but also an excellent way of covering current trends of the polymer industry in o ur university courses. Our s tudent s enjoy, and benefit tre mendou s l y from, a knowledge of the se current indu s trial trend s. UNDERGRADUATE COURSE Table 5 present s the sy llabus of the introduc tor y polymer course given in the Chemical En g ineering Dep a rtment at the University of Wa terloo. It is offered annually (6 hours per week) as a technical elective co ur se for senior un dergraduate s tudent s and as an introductory co ur se for graduate s tudent s who are pur s ing MASc and PhD d eg ree s in polymer sc e nce and engineering. Thi s course covers th e main areas of polymer reaction engineering for s tep-growth and chain grow th polymerization. Special emp ha s i s i s put on under s tanding fundamental polymerization principle s, u si ng both experimental polymer i za tion data and mathematical modeling tech nique s. Th e s tati s tical n a ture of polymerization i s examined in detail to ge ther w ith the concepts of molecular weight and chemical composition di s tribution in polymer s. Polymer chara c teriza tion technique s are introduced as tool s to corre late polymer chain s tructure to polyme r ization mechanism s and proce sses Several modern po lymerization proces ses ( free-radical emu l s ion s u s pen sio n and solution, as well as Ziegler Natta and metallocene -ca talyzed processes) are pre s ented to illustrate the fundamental concepts covered in th e initial part of the course. The experience gained by our interaction with in dustry via co ll aborative research projects and s hort courses help s u s identify the mo s t re levant 65

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polymerization processes for this section of the course In this way it has been possible to design a course with a strong industry-oriented component while at the same time main taining a high level of scientific and academic content. projects Our interaction with polymer manufacturing com panies has been beneficial in defining polymer-related re search and design projects Some of these projects are de scribed in Table 8. The course components consist of bi-weekly assignments a mjd-term exam and a final exam. Graduate students are also required to work on a project, results from wrnch are presented orally at the end of the course Table 6 shows a selective list of required and supplementary references for the course. In addition to these references, several technical articles describing the state-of-the-art in polymerization re action engineering are given to the students as recommended reading throughout the course. CLOSING REMARKS University-industry interaction via industrial short courses and collaborative research projects can bring several advan tages to both academic and industrial participants. As a result of our own experience with short courses we have been able to design academic cour s es with a high content of industrially relevant material. Instead of jeopardizing the academic and fundamental content of these under graduate and graduate courses this approach has actually stimulated the students to better understand the mecha nistic and fundamental aspects of polymerization pro cesses that have prominent application in both academia and industry In order to familiarize students with the vast amount of literature available in polymer science and engineering on line literature searches are also conducted during the course in collaboration with our library personnel. Computer simu lation case studies in polymerization reaction engineering are also done using WATPOLY, a user-friendly package developed at Waterloo for the dynamic simulation of solu tion, emulsion, and suspension polymerization reactors. In trus way several complex aspects of On the other hand, industrial short courses that bring re cent fundamental scientific advances to industrial applica tions have helped clarify or show different solution alternathese polymerization systems can be examined by the students without the need of tedious and time-consuming calculations. Additionally the course is comple mented with a tour to the polymer ization pilot plant facilities of the de partment and with site visits to poly mer manufacturing and processing companies in the region. Samples of polymer reaction engi neering-related problems (tests or as signments) that have arisen from our industrial interactions are presented in Table 7. Some of these problems are open-ended and may have mul tiple solutions. They are an extremely powerful vehicle in giving the stu dents a flavor of "real world poly mer production problems SENIOR-YEAR DESIGN/RESEARCH PROJECTS All fourth-year undergraduate stu dents have to complete either an in dividual research or design project or a group process design project in di rect collaboration with one faculty member. Several Canadian and American companies sponsor these 66 TABLE6 Textbook and Supplementary Reading Allcock and Lampe Con.t e mporar y Pol y m e r Ch e mistr y, 2nd ed Prentic e Hall ( 1990) Bi c erano Pr e di c ti o n of P o l y m e r Prop e rti es Marcel Dekker (199 3) Billingham M o lar Mas s M e asur e m e nts in Pol y m e r S c i e n ce Kogan Page Ltd. (19 77) Billme ye r T ex tb oo k o f P o l y m e r S c i e n ce lnt e r s cienc e ( 1984 ) Brandrup and lmm e rgut P o l y m e r Handb oo k John Wil ey & S o n s ( 1975 ) S ev eral a uthors C o mpr e h e n s i ve P o l y m e r S c i ence, 7 v olume s P e r g am o n Pre s s (1988 ) Dotson G a lvan L a uren c e a nd Tirr e ll P o l y m e ri za ti o n Pr ocess M o d e lin g VCH Publisher s (1996 ) Elias Ma c rom o l ec ules 2 volumes Plenum Pr es s (1984 ) Flor y Prin c ipl es of P o l y m e r Ch e mi s try Cornell Uni v er s ity Pre ss ( 1953 ) Grulk e y Pol y m e r Pro ces s En g in ee rin g Prentice Hall ( 1994 ) Gupt a and Kumar R e a c ti o n Engin ee rin g o f St e p Gro w th P o l y m e ri z ati o n Plenum Press (1987 ) Ham Vin y l Pol y m e ri z ati o n Marcel Dekker ( 1 9 67 ) Hi e menz P o l y m e r C h e mi s tr y: Th e Basi c C o n ce pts Mar ce l D e kker (1984 ) McCrum Buckle y, Buckn a ll Prin c ipl es o f P o l y m e r E n g in ee ri ng Oxford Univer s ity Pre ss (1988) Moad and S o lomon Th e Ch e mist ry of Fr ee Radical P o l y m e ri z ati o n. Per g amon Pre ss (1995 ) Odian Prin c ipl es o f P o l y m e ri za tion 3 rd ed. McGraw-Hill ( 19 9 1 ) Peeble s Mol ec ular W e i g ht Distribution in Pol y m e rs Int e rscienc e ( 1971) Rabek E x p e rim e ntal M e th o ds in P o l y m e r Ch e mi s tr y John Wil ey & Son s (1980 ) Rempp and Merrill Pol y m e r S y nth e si s Huthi g /Wepf V e rla g (1986 ) Rodri g ue z Prin c ipl es of P o l y m e r S c i e n ce McGraw-Hill ( 1970 ) R o s e n Fundam e ntal Prin c ipl e s of P o l y m e ri c M a t e ri a l s John Wil e y & Son s (1993 ) Rudin Th e El e m e nt s o f P o l y m e r S c i e n ce and En g in ee rin g A ca d e mi c Pr ess ( 1982 ) Saunder s Or g ani c P o l y m e r Ch e mi s 11 y Chapman and H a ll ( 19 88) Sperlin g Intr o du c ti o n t o Ph y sical Pol y mer S c i e n ce, 2nd ed. John Wiley & Sons (I 992 ) v an Kr ev elen Pr o p e rti e s o f Pol y m e rs El s evi e r ( 1990 ) Chemi c al Engin ee ring Education

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TABLE7 Polymer Reaction Engineering Problems Assignments and Exams PROBLEM 1: Given the following data calculate ( at O and 50 % conversion): ( a) the instantaneous number average chain l ength of the polymer and (b) the average lifetime of a growing c h ain. Neglect chain tran sf er and assume that t em1ination is by di s proportionation on l y DATA : k= 900 Umol.s; k ~ / k 1 = 2.3 14 L/mol.s; k d = 3 x J0 5 1 ; 1 0 = 0.017 mol/L ; M 0 = 1.5 mol/L ; PM = 0.91 g/cm 3 PROBLEM 2: MMA is being polymerized in solution in a batch reactor using AIB as initiator. The solvent is ethy l ace t ate and the contents are maintained at 60 C. The rea ctor i s initially charged with 75% by vol um e MMA, 25 % by vo lume ethyl acetate, and enough initiator to ac hi eve l 0 =0.05 mol/L. Compute a nd plot (a) rate of polymerization (b) heat of polymerization, and (c) number average molecular we i g ht as a function of polymeri za tion time. DATA: K p0= 170 Umol.s; k, 0 = 1.85 x 10 6 L/mol.s; k d = 7.5 x 10 6 s'; k,/k P = 0.00014; PM = 0.91 g/cm 3 ; P s = 0.85 g/cm 3 ; f = 0.5 PROBLEM 3: Redo Problem 2 u s in g the following gel-effect functionality for th e termination rate constant: k =k, 0 for x S: 0.36; k = O. I 296(k ,J x 2 ) for x > 0.36. PROBLEM 4: Find th e rea ctor volume, total flow rates and average residence time to produce I 0 000 ton/year of styrene-acry l onitri l e bulk copolymer co ntaining 28% (mole) acrylonitrile (365 days/year 24 hour s/day) If you need to m ake assumptions state them clearly and justify them. Assume that the total conversion in 60 % DA TA: r = 0.41; r = 0.04; k 11 = 176 Umol.s; k 22 = 2500 Umol.s ; k = 5 x I 0 5 L/mol.s; p 1 = 0.903 g/cm 3 ; p 2 = 0.811 g/cm 3 ; R 1 = 10 1 mol/L.s; M, = 104 g/mol ; M = 53 g/mol. () = styrene, 2=acrylonitrile) PROBLEM 5: Cons id er a CSTR free-radical polymerization operating at steady state. Using the following data, map out the possibilities for s t ea dysta te conversion ve r s u s residence lim e. How would yo u achieve 75 % convers ion ? For results uniformity, consider a reactor operation of 365 day s/year and 24 hour s/day DA TA: I = 1 0 = 0.0 I 7 mol/L ; M 0 = 1.5 mol/L ; k 1 0 = 3.5 x J0 5 Umol.s; k d = 3 x J0 5 s ; k p0 = 900 L/mol.s ; f = I k, = k, 0 for x $ 0.2 a nd k = (k,J0 512)( l-x )3 for x > 0.2 k P = k p0 for x $ 0.85 and k P = (k~0.0225)( 1-x) for x > 0.85 PROBLEM 6: An isothermal polymerization is carried o ut a t 100 C w ith a dual initiator system. After three hours of polymerization the monomer conversion is 60 % in a 40,000-liter batch reactor. (a) Calculate the total radical concentration at 60 % conversion of monomer (k,d= 10 5 Umol.s); ( b ) How long does it take to grow a polymer cha in of molecular weight equal to I 0 5 at 60 % convers ion ? (c) Find the instantaneous heat generation rate at 60 % conversion. Compare this with the value a t zero convers ion ; (d) Calculate instantaneous M and M w at 0 % and 60 % conversion; (e) The growt h in M w at hi g h concentra tion s gives too broad a MWD The solut i o n is to use a chain transfer age nt (CTA). Find the amount of CTA r eq uired to keep M w a lmost consta nt over the conversion int erval 0-60 % give n that k = I 00 Umol.s. Compare M w va lue s at 0 % conversion for cases with and without CTA DATA: I ID =2xlO -' mol/L; 1 20 =5xI0 3 mol/L; MW=l00g/mol; (-t,Hp)=l7kcal/mol; k, d 0 =10 7 L/mol.s ; k d 1 =10 5 s 1 ; k d 2 =10 4 s 1 ; M 0 = 10 mol/L; k = O; k = !0 3 L/mol. TABLES Some SeniorYear Design/Research Projects Dynamic s imul at ion of ethylene-propylene impact copo l y mer s in a series of CSTRs Copolymerization kinetics of methyl methacr y late /vi nyl acetate Terpolymerization kinetics of methyl methacrylate/vinyl acetate/ butyl acrylate tives to severa l problems encountered in industry. The ques tions raised during these short courses have resulted several times in new research projects at both the undergraduate and the graduate level. In the proce ss of attempting to tackle these industrially related problem s, novel fundamental knowl edge is generated, pu s hing the boundaries of our knowledge in polymer science and engineering even further. Inv est igation of kinetics of a-methyl sty ren e/methyl methacrylate at elevated temperatures Investigation of butyl acrylate homopolymeri zat ion a t hi g h conversions Modeling of suspension polyvinyl ch lorid e r eactors Educational u ses of a general polymerization s imul ato r package Injection molding of medical plastics Gel content in polyethylene/pol y propylene sheets Winter 1998 NOTE As a point of information for the academic readers of this article, we are planning a series of short courses to assist chemical engineering academics who are teaching or wish to teach polymer-related courses at the undergraduate level. We welcome all communications from interested academics who would like to either attend these short courses or to give lectures on undergraduate courses in the polymer area that they have successfully given. 67

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taa~a--c :: ,a = s = s ~ ro=o ~ m =--------) PRACTICAL TIPS FOR GATHERING INFORMATION SAIDAS M. RANADE Consultant Hou ston, TX 77079-2995 E n gi neer s working in process plant s are problem s olvers. They play a ve r y important role in ~roce ss plant trouble s hooting For example, consider the following s ituation: The quality of a product from a ce rtain unit has b ee n de grading for some time and for some unknown" reason. You are a plant support engineer and yo u have been called upon to help. Your job is to identify the root ca use, to quant ify the busine ss benefit s of solving the probl e m, and then to suggest ways to eliminate the factors causing the probl e m What is problemso lving and how doe s it begin ? The ver b "so l ve co me s from the root solve re, which mean s "to loosen relea se, or se t free." The word "problem" comes from the roots pro, meaning "fo rward, and ballein, meaning to "t hrow or dri ve." So, problemso lvin g is a proce ss of propo s ing and considering question s in a way that throw s or drives u s forward toward greater freedom. 111 In their entertaining book, The Universal Traveler, Don Koberg and Jim Bagnall define the seven s tages of creative problem so lvin g as "acce ptance analysis definition ide ation, idease lection implementation, and evaluation." 1 21 Clearly, being aware of a problem 's existence i s the fir st s tep G a thering information about the si tuation is the next s tep On e can learn about the s ituation through literature and document searc he s, by direct observation, and by gathering information from people clo sest to the problem Thi s ski ll of ga therin g data from others i s a critical s ucce ss factor for all practicing e ngineer s. Wherea s ga thering information from literature and the Internet is emphasized in mo s t engineering co ur ses, to the be st of my knowledge, training in how to gather information from others is not offered The main objective of this article is to s hare some practical ideas on improving the speed and effectiveness of the pro cess of ga thering information from others. It is ba se d on m y experience in designing and conducting opportunity and s up port need s assessment surveys for proce ss modeling in process plants. Although the article will focus on techniques for more organized information gathering (s uch as s urve ys and on-site visits), the principles illustrated are equally appli cable to informal information exchanges. This domain of designing and conducting s urvey s ha s been de ve loped ex tensively by social scientists. I will begin first by defining the prerequi si tes for effective information exchange and then I will provide s pecifi c guidelines on ho w to pose the right question s. The article will also include a brief di cussion on how one might be able to u se this information in a classroom sett in g KEY PRERE Q UISITE S Early in m y caree r I learned that comm unic atio n consists of a me ssage, a se nder a receiver a medium a context feedback, and noi seY 4 1 For gathering information the me sage i s the que st ion s," a nd the medium ma y be a print e d survey or a face-to-face interview (i.e., s pok e n words). I have discovered five ke y prerequisites nece ssa ry for cre ating the right context, capturing the feedback and minimizin g noise Trust Thi s is the first prerequisite. Thank s to authors such as Peter Senge 151 and Stephen Covey, 1 61 di sc us s ion s on trust and trusting are becoming mor e acceptable even among hard-core engineers. Tru st i s the foundation of all effective communication. The survey recipients mu st clearly under stand the purpose of the information exchange They must know why" the information is bein g reque sted and how Sai d as M. R a n a d e PhD, PE was t he Principal Consultant for Aspen Technolog y Inc s Model ing Success Program Some of the tools he has de velop ed and applied to ensure that cus tomers get the best value from AspenTech s modeling technologies and services include modeling opportunity assessments modeling needs assessment a template for documenting successes and a method for cataloging pro cess models He can be reached at smranade @ neosoft .co m Copyright ChE Di vision of ASEE 1998 68 Chemical Engineering Edu catio n

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their information will b e u se d .l 7 8 1 It i s the int e rvi ewe r 's obligation to pur s u e the truth and truly beli eve in doin g every thin g to b en efit the inter viewees. O f co ur se, trust can not b e mand a t e d and there are no s hortcut s to building trust. V e ndor s of software and associated serv ice s h ave the challenging t ask of overcoming a histor y of la ck of tru s t created by their industry-for exa mple cus tomer s do not believ e in sof twar e release dat es. Al s o in dealin g wi th pro cess manu facturing plant s, the issue of confidentiality of information i s very important and must be ex plicitly addressed prior t o a n y u sefu l information-g a th e rin g sess ion. The main objective co m for tabl e a nd ope n with severa l w hit e b oards and ease l s. Durin g a sc h e duled plant turnaround a plant is typically s hut down for severa l weeks Thi s p er i o d is u se d to make major modifications to the process and to install new plant eq uipm e nt. Many of these n ew it e m s ha ve to be ordered s i x to nine month s in advance an d it takes a bout thr ee t o six months to d eve lop detail ed s p eci fic a ti o n s for maj o r items. So the b est time to co ndu ct opportunity assess m e nt s i s about nine to fif t ee n months pri or to a sc heduled turnar o und In th is mann er, th e recommended r evampt ype projects can b e implemented durin g the turnaround p erio d of this article is to share some practical ideas on improving the speed and effectiveness of the process of gathering information from others . . Although the article will Credibility and Respect Th e seco nd prer e quisite to effective inform a ti o ngat ering i s the interviewer 's credibility in the domain of the s pecific inquir y. P eo ple are more open to a n sweri n g your question s if you have already established a tr ack r ecord, either with the si te or the pro cess or the focus on techniques for more organized information gathering (such us surveys and on-site visits), the principles illustrated Gratitude Thi s i s the fifth pr ere qui s ite. It h e lp s immensely if yo ur demeanor co veys a ge nuin e se n se of gra titud e to wa rd tho se fro m w h o m you co llect information In today 's atmos ph e r e, it see m s that everyo n e s age nd a is full a ll th e time so are equally applicable to informal information exchanges. field of inquir y (i e., if th ey respect yo u ). There are pro s and cons to this ph e nomenon You may b e ve r y talented a nd m ay ha ve a novel approach to so l vi n g problem s; but yo u m ay not b e effec tive s impl y b eca u se yo u are ne w. A l so, du e to thi s emphasis on "c redibilit y," it i s ve r y t e mptin g to u se th e jar go n of the bu s ine ss s uperfi c iall y t o esta bli s h cre dibil ity but experience h as s ho w n me that in s tead of a tt e mp ing to appear kno w led gea bl e, it is b etter to ad mit th at you a re new to the field. Effective Listening Thi s is the third prere qui site H o n est and open exchange of id eas is possible only w hen yo u ha ve a ge nuine intere s t in the v iew s a nd opinions of the interviewees One of the be s t d efi nition s of effec ti ve li s ten ing comes from Dr. St e phen Covey. H e e quate s effec ti ve li s tening to faithful tran s lation. Th e main requir e ment to ha vi ng a dialogue and not ju s t a discussion is to be com plet e ly open to th e outcome Thi s is at the h eart of any tru e di scove ry proce ss. The word "dia lo g u e" comes from two Gr ee k roots: dia, m ea nin g "t hrou g h ," and logos, m eani n g the word." It c arrie s a se n se of m ea nin g flowing through ." The word di sc u ss ion ," on th e other hand ste m s from th e Latin discuter e, which mean s t o s ma s h to pi eces." Addi tional u se ful information on the topics of Inquiry" and The Art and Practice of Conversation is pre se nted in Ref. 5 Proper Timing and Setting This is the fourth prerequi site. One of the biggest challenges for engineers and opera tor s in proce ss plant s is to make time available for s ur veys and audits. Hence the s urve ys must be aesthetically d signed and the participants should be given ample time to complete them. In a face to-face inform a tion-gathering ses sion, the room in which interviews are co nducted s hould b e Wint e r 1998 even if yo u do not find some of th e responses t o b e u seful, it a l ways make s sense to th a nk the interviewees or s ur vey parti ci pant s for their tim e. It is a l so important to publicl y acknow led ge any co ntribution made by others to the s u ccess of yo ur projects GUIDELINES FOR POSING QUESTIONSl 7 9 l After h avi n g satisfied the above prerequisites, one ma y sti ll not b e effective i n cond u cti n g s ur veys and on-site inter v i ews This is w her e th e "s cience of aski n g que stio n s comes into play The fo ll owi n g quotes and even t s sig nif y t h e im p ortance of questions a nd qu estio nin g: "Yo u ca n t e ll w h et h e r a man i s clever by hi s a n swe r s. You can tell w h e th er a man is wise by hi s que s tion s." Naguib M a hf o u z Winner No b e l Prize for lit erat u re, 1 988 [ 1 1 When Richard F ey nman was a c hild h is Mother asked th e future Nobel Prize winner the same question every eve nin g at t h e dinner table : What did yo u ask at sc h oo l t oday, Richard ?" (Feynman won the Nobe l Prize for physics in 1965. )l' 1 H amm u ra bi of B a b y l o n c h a n ge d th e co ur se of hi s t o r y by c h ang in g the repre se nt ation w h e n dealing w ith the prob l em of an inadequate wa t er su ppl y In s tead of aski n g how to get th e peopl e t o the water, he aske d how to ge t th e water to the peopl e. Thi s led to the inv e ntion of ca n a l s l 101 Creation of the proper context is neces sary for both printed s ur veys and on-site inter v iew s In a printed survey, the content a nd the o rder of the que s tion s mu s t b e carefully se l ec ted In a face-to-face interview, in addition to the choice of words and th e ir sequence, proper tone of your voice plays a ve ry important rol e. 69

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I will begin with a brief discussion of different types of questions Then I will provide guidelines on wording of questions and maintaining a flow for the on-site interviews. Types of Questions In his book Just So Stories (1902), Rudyard Kipling (who won a Nobel Prize for literature in 1907) had this to say about types of questions: I keep six honest serving men They taught me all I know. Their names are What and Why and When and How and Where and Who The "how"-type question is the most open-ended The "why" -type question may put the interviewee on the defensive. At some point in time, the questions beginning with why are essential to finding the cause of the problem; initially they may not be very effective however. Yet another method of classification also results in six types of questions. They are questions pertaining to experi ence/behavior, opinions/values knowledge feeling, sensory, and background (or demographics)_L 9 J For each type of ques tion one can ask about the present the past or the future. Questions pertaining to experience or behavior or actions are easy to answer and should be used first. Sensoryand background-type questions are mundane and should be dealt with toward the end of the on-site interview. Questions pertaining to participants opinions/values and knowledge are very important for identifying symptoms and causes of problems, but they require proper context-building prior to their use. It is important to gauge the level of an individual's knowledge about a given situation without making it seem that you are testing him. Engineers, in general tend to shy away from "feelings"-type questions and, hence, they should be kept to a minimum For the time-frame, it is always appropriate to start from the present and then move to the past and then to the future GUIDELINES ON PROPER WORDING [[ a 9 1 Basics First, ask truly open-ended questions. How satisfied are you with the performance of this heat ex changer?" may seem like an open-ended question but it is not. Second it is important to ask a "singular" question (i.e., refer to only one idea per question). A good question should be relatively short, clear, and unambiguous Do not run a string of questions together. If you want to ask a string of related questions, then ask one at a time and get a response before proceeding.t 111 The question, "How often do you mea sure the pressure drop across this exchanger, how good are the measurements, and do you know the cause of the sudden increase in the pressure drop?" should be split up into three separate questions. The third basic rule is to use the terminology and language of the interviewee or survey-recipient. Be careful of acro nyms such as QIT, BIP PIP, etc ., because they may have different meanings at different plants. If you do choose to 70 use acronyms it is always beneficial to define them A Few No-No's In the beginning avoid questions that result in "yes or "no" responses. The whole idea is to get the participants to "open up." Also avoid why" questions in the beginning From our childhood, we have been condi tioned to associate some type of blame with the word why. ("Why did you break this vase?) The objective of gather ing information from others is accomplished when you make them feel comfortable about the situation and encour age them to have a dialogue with you. P r oven Techniques Presupposition-type questions are good For example "What is your most important idea regarding the cause of fouling? This question presupposes that the interviewee is capable of having several good ideas about the cause of the problem. Questions pertaining to tough topics or questions that seem too direct can be soft ened considerably either by role playing (i.e. putting your self in a new role in the question) or by simulation (i.e., putting the interviewee in a new role in the question). Rather than asking, What do you do in the plant in the morn ing? ask, "If I were your colleague accompanying you in the plant what would I observe? And instead of asking a unit engineer What are the goals of the entire plant?" try, "If you were the plant manager, what would be your top priorities? Keeping the Flow It is very important to keep the on site interviews flowing smoothly. This depends on several factors. Establishing rapport with the individual and main taining neutrality toward the information they provide are very important steps for keeping the flow. It always helps to make transitions smooth rather than abrupt by making spe cific announcements before the transitions. Prefatory state ments such as, "The next question may seem a bit vague ," are very useful to ensure that the interviewee is not under undue pressure to look for a precise answer. Elaboration clarification, and contrast-type probes are very useful in getting some individuals to talk. Of course, thanking the interviewee for providing a response to a tough question is also effective in keeping the flow of the process. In general it is very hard to get engineers to converse openly with you but occasionally you will come across individuals who try to monopolize the conversation and will not stop talking. In such cases it is important to emphasize in a conver sational tone of voice, that everyone s time is important. The flow of the process can be easily disrupted by Jong winded or irrelevant comments CLASSROOM APPLICAT I ON OF THIS MATERIAL One easy way to make students aware of the issues in volved in gathering information from others is to ask stu dents to read this article and spend about an hour discussing the topic in the classroom As an additional homework assignment, you may ask students to watch the 1996 TwenChemical Engin e ering Education

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tieth Century-Fox movie Courage Under Fire which clearly demonstra t es that the same event (or a problem) can be perceived very differently by different people. Since the right psychology and information ma y not exist readily in most chemical engineering classrooms the only way to di rectly practice the techniques pre sc ribed in thi s article is by simulating a few real-life situations in a classroom setting and requesting students to play specific roles. One s uch approach, which requires a fair bit of preparatory work, is described in the Apppendix. CONCLUSION Engineers and managers are problem solvers. An impor tant step in identifying and defining problem s involves gath ering data. Since every situation is unique, it always help s to gather information about a situation from the people who are closest to it. T h e technique s for gathering information from others are very important for proce ssplant trouble shooting and are not emphasized enough in formal chemi cal engineering education. The main point is that one will be able to easily acquire useful information from others by ensuring that the prerequi sites such as trust respect effective listening, proper timing and gratitude are met and following the guidelines for cor rect wording, sequence, and tone of the question s. Practic ing the techniques without the prerequisites is possible but only results in manipulation and deception and s hould be avoided at all costs. ACKNOWLEDGMENT The opinions expressed or implied are those of the author and do not represent the views of AspenTech. REFERENCES 1. Gelb, M.T., Thinkin g for a Change Harmon y Books New York NY 96 ( 1995 ) 2. Koberg D., and J. Bagnall, The Universal Traveler, Crisp Publications Inc Los Altos CA, 41 ( 1991 ) 3. Wurman, R.S. Follow the Yellow Brick Road Bantam Books New York NY 17 ( 1992 ) 4. Salsbury G.B. A R esource Manual For Effective Pr esenta tions Salsbury Communications, Inc ., Manhattan Beach CA ( 1985 ) 5 Senge, P.M. et. al. Th e Fifrh Dis cipline Fieldbook Cur rency-Doubleday New York NY ( 1994 ) 6 Covey, S.R., Prin ciple-Centered L eade rship Fire side, New York NY ( 1992 ) 7. Salant, P., and D .A. Dillman H ow to Conduct Your Own Survey, John Wiley & Sons Inc. New York, NY ( 1994 ) 8. Sudman, S., and N.M Bradburn Asking Questions: A Prac tical Quid e to Questionnair e D esign, Jo seyBass Inc. San Francisco CA ( 1982 ) 9. Patton M.Q., Qualitati ve Evaluation and Research Meth ods, 2nd ed., Sage Publications, Newbury Park CA ( 1990 ) 10 Rubenstein, M.F., and I.R. Firstenberg "Tools for Think ing in Developing Critical Thinking and Problem-Solving Abilities, Ed., Stice, J.E ., Josey-Bass, Inc ., San Francisco CA ( 1987 ) Winter 1998 11 Wankat P.C., and F.S. Oreovicz Teaching Engineering, McGraw-Hill, Inc. New York NY, 101 ( 199 3) 12 Lieberman N.P ., Troubl es hooting Process Operations, 3rd e d ., Penn Well Books Tulsa, OK ( 1991 ) 13. Saletan D ., Creativ e Troubleshooting in the Chemical Pro cess Indu stries, Chapman & Hall New York, NY ( 1994 ) APPENDIX An Experiment for Tes t ing the I d eas in a Classroo m Setting Preparation At the beginning of the experiment, divide the students into groups of five. Provide each group with a handout or script describing a specific si tuation Examples of such situations include safety incidents environmental excursions, product quality problems, etc You may u se the published case s tudies from books s uch as tho se by Lieberman ,l' 21 Saletan, [ 131 etc., to create the s pecific scenarios. On each team assign one of the following roles to each student Operator Plant Engineer Tech-Support Engineer from a Central Group Plant Manager Chemist Assigment To identify, define and so lve problems faced by all the other teams. Rules Give students about four weeks to complete the assignment. Request that the students Not reveal the actual script or handout to anyone outside of their team Play the assigned roles as faithfully as possible Only answer the question s being asked while remembering the mind se t of the role they are pla yi ng Document their strategy for gathering the required information Document their feelings, thoughts, and any other reactions to the mode of inquiry used by each of the other team s. Criteria for Grading Number of problems identified Number of problems solved Nature of the mean s used to obtain information Impact on the feelings of others during the pro cess of gathering information Quality of the document describing the strategy used to acquire information Quality of the document de sc ribing the feelings and tho u ghts during the inquiry by other teams 0 71

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~b=i looking back ) ----------=-------ADVICE FROM AN OLD-TIMER w. DAN MACLEAN Pinnacle Technology Inc. Lawrence KS 66044 P rocess engineers s uch as my se lf who are approach ing retirement or are at an age where "yo u can see it from here ," probably received their undergraduate trainin g in the 1950 s As we consider the prospect of retirement or edge into it throu g h part-time work or consulting jobs, it is intere s ting to consider how we dif fer from today 's graduate. There i s little question that today's graduate i s better equipped with the tools of the trade and better prepared to be immediately useful. But it can be argued that my genera tion spen t an apprenticeship doing hand calculations that were more productive. For example, hours, if not day s, were spent checking a heat exchanger design by hand giving us a better feel for the variables involved than doing computer iteration s would But time soo n evens everything out. So what can my generation pa ss on to new proce ss engi neer s? Perhaps some rules-of-thumb that have been useful or some g uid elines for good practice, or some judgmental discernments that we have learned through unfortunate ex perience s. What follows are so me of the rules and guidelines that have proven useful to me over the years. STREAM EFFICIENCY The stream efficiency, or annual on-stream operating time is a key factor in successfully operating any chemical plant. Plant s are designed to run on gallons per minute, or pounds per day or barrels per stream day But cash is generated and investors are rewarded from tons per annum, or pounds per year, or barrels per calendar day. A key number to remember is 8760-the number of hours in a year. In a perfect world that is error and maintenance free, a plant would produce in a year 8760 times what it cou ld produce in an hour. But allowi n g for a two-week annual maintenance s hutdown and an unscheduled outage of one day a month the operating hours in a year are actually 8136, for a stream efficiency of 93 % In actual practice, a promise of more than 8000 operating hours in a year (or a stream efficiency of 91 %) i s highly s uspect. Oil refineries that are well run and well maintained show that s tream efficiencies in the 90s are difficult to achieve The refining industry as a whole probably operates with a stream efficiency in the mid-to-high 80s. Projected high s tream efficiencies often s t e m from mas sagi ng the number s to improve a project's economics, and name plate" ca pacitie s are prob a bl y derived from a 72-hour test run or whatever was contractually agreed upon at the beginning. R emember though that the real test run i s the 8000-hour te st. One should u se 8000 operating hour s per year as the goal even when giving appropriate consider ation to feed outages, power interruption s, changing prod uct grades, etc. ECONOMIC ANALYSES: TOP LINE VS. BOTTOM LINE There are many exce llent guides to preparing eco nomic projections for a new project. For the mo s t part these g uid es focus on developing the bottom line ," i .e., net profit cash flow payback etc. That i s what owners and investors want to see Much useful information however can be obtained from an analysis of the "to p line ," i. e., the total sales generated. One should look at sa l es generated per dollar invested in much the same way as s tock analysts look at a co mpany 's sales -p er-share. How many time s per year the sales tum over" the capital invested can lead to a good appreciation of a project 's risks and rewards. Assume annual sales per invested dollar are s ub s tantially greater than one; unle ss the project i s the proverbial license Dan Maclean graduated from the University of Toronto with a BASc in chemical engineer ing in 1954 and received his MASc in chemi cal engineering from Birmingham University (United Kingdom) in 1959 He worked for Celanese Corporation and for several oil refin eries during his career, and since 1984 has had a wide range of cons ulting assignments usually in the area of alternative fuels such as alcohol/gasoline blends and pyrolysis oils Copyright ChE Diuision of ASEE 1998 72 Chemical Engineering Education

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to print money the margin per sales dollar is going to be thin Examine the margin carefully. How firm is it ? A small reduction in the margin could eliminate any profit. I s the operation a value-added one, s uch as refining crude oil where the margin is protected by a direct link between raw material and product prices? If a large volume of raw materials and products is involved, has sufficient attention been paid to materials-handling factors? Concentrate on the cost factors involved in the project. HEAT EXCHANGERS Without que stio n the mo s t common mistake made in s peci fying heat exchangers is made by the conservative engineer anxious to supply adequate equipment who s pecifies too much area! By a unit that i s too big, fluid velocities are reduced to les s that 3 feet/second, transfer coefficients fall, and deposits build up in stagnant zones. Performance is poor and even, in so me cases, inadequat e Three feet/second is the absolute minimum velocity, s hell or tube s ide, that should be considered. Providing the head required is a small price to pay for good heat exchanger operation. A rapid way to estimate the number of tubes in a s hell and tube exchanger is with the formula N = C(L/P) 2 where N numb er of tubes P tube spacing, inches L "o ut er tube limit, inch es C constant, 0.75 for square pitch, 0.86 for triangular pitch The "o uter tube limit i s 5/8 in le ss than the s hell diameter for fixed tube sheet or U-tube construction, and 1 1/2 in. le ss for floating head construction. Assume 20-inch nominal s h e ll diameter ( 19 .2 -inch inside diameter ) 16-ft tube l e n gth, fixed tube s heet 3/4-inch tubes on I-inch sq uar e pitch N = 0.75 ( I 8.575/1 ) 2 = 259 tubes Area = (259)( 16)(0. 196) = 8 I 2 sq. ft. or assume As above, but with I -inch tubes o n I 1/4-inch triangular pitch N = 0.86 (18.575/1.25) 2 = 190 tubes Area = ( 190 )( 16 )(0.262) = 796 sq. ft. This formula neglects tubes lost due to multipass construc tion impingement plates etc. PUMPS The old adage, "A ll pump problem s are s uction prob lems ," s till applies. Design for low velocities in s uction lines: 0.5 to I foot/second for boiling liquid s, and 1 to 3 feet/ second for non-boiling liquids. Vortex breakers are often omitted or ignored. Cros s or flat Winter 1998 T here i s littl e question that t oda y's g raduat e i s better equi p ped wi th th e tool s of th e tr ad e" and better prepared to be i mmedia t el y u s eful. But it c an b e ar g ued that m y generation spe n t an apprentic es h i p doing hand c alculations th a t w ere m or e produ c ti v e plate b affles, with a width of 2 to 4 times the nozzle diameter and a height of one-half the nozzle diameter are effective vortex breaker s. PLOTS AND COUNTERPLOTS A company I once worked for operated some acetylation kettles in which sheets of cellulose (wood pulp) were acety lated with acetic anhydride. The kettles were jacketed with a recirculating brine to remove the heat of reaction. Brine circulation was controlled manually to prevent rising tem perature s from degrading the cellulose and falling tempera tures from reducing the reaction rate. Varying temperatures, humidities and time in storage of the cellulose resulted in varying moisture levels in the cellu lose This resulted in varying reaction temperatures and the recurring question-were we overor under-controlling? Were we looking at random noise when the temperature wandered, or had reaction conditions actually changed? Routinel y, we plotted kettle temperatures to see to what extent we were di verg ing from set point. Next, we initiated a new plot for every five minutes, s howing the cumulative extent to which temperature diverged from the set point. If the temperature was cycling randomly around the set point, thi s second curve would make an exaggerated cycle but would return to zero (see Figure 1) If, however reaction conditions had changed and a new equilibrium temperature had been established, the second plot would rapidly indicate this by going outside any boundCUMULATIVE DEVIATION FR0!1 SETPO l 1'T \ Fig u re 1 TI M E 73

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C U MULAT I VE DEVIATION FROM SET PO I NT TIME Figure 2 ary limits (see Figure 2). Boundary limits can be readily set after so me operating experience The same kind of plot can be u se ful in any s ituation where you want to establish if a s tatu s quo si tuation or an existing trend line had been breached They can be used along s ide moving average plot s in financial quotation s. Another plot I have found u sefu l i s the probability paper both normal and logarithmic. A probability paper i s mo s t suited to record a ser ies of events di str ibuted around a mean where one wants to de sig n for a certain fraction of the occurrence of the events. The se events could be temperature TABLE 1 Daily Truck Loading DailJ_ Truck Loadings in Asce11di11g_ Order #of Day number #of Truck s Trucks M Loaded, [M/(N+l)) Loaded in order 60 1 28 0.048 40 2 3 0 0.095 85 3 34 0.143 30 4 38 0.190 67 5 40 0 238 46 6 40 0.286 60 7 42 0 .333 42 8 45 0.381 90 9 46 0.429 51 10 50 0.476 53 11 5 1 0.524 62 1 2 53 0 .57 1 34 13 60 0.619 73 14 60 0.667 80 15 62 0 .7 1 4 50 1 6 67 0.762 38 1 7 73 0.810 28 1 8 80 0.857 40 1 9 85 0.905 45 20 ( N ) 90 0.952 53 7 Avg. 74 99.99 99.9 99.5 99 9S 90 70 60 30 10 o 5 0.' 0. 1 " 60 100 DA I LY TRUCK LOAD I NGS Figure 3 or wind level s, s hip arri va l s, ri ve r flow s, etc As an example consider dail y truck lo a din gs a t a terminal. Th e number of truck s per d ay is tabul ate d by da y M in Table 1. Next, arrange them in ascending order and divide M by (N+l), where N i s the total number of day s, and plot "M" /(N+ 1 ) vs the number of trucks/day or probability paper. The data align s rea s onabl y well (see Figure 3). To satisfy the loading demanded four day s out of five, or 80 % of the time inventory would be required to fill 70 truck s. If it was de s ired to sa tisfy the loadin g demanded nine day s out of ten inventor y would be required to fill 85 trucks LINE SIZING The guideline 1 pound per 100 feet" pressure drop can serve to size line s in a wide variety of situations. The tables in Cameron Hydraulic Data, based on the Williams and Hazen formula, form a conservative s tandard Two point s worth mentioning here are: 1 ) In lon g, lar ge -diam eter l ines, hold the ve l oci t y down to a walking pac e of 4-5 mile s per hour o r 67 feet per second. 2) I 1/2-in. sc h 40 pip e is th e s mall est s i ze that w ill s pan 15to-20-foot pipe racks without intermediate s upport. Opera tors often climb on pipin g to take readings, e tc. so 1 1/ 2 -in pipe i s th e s mallest pipe size that s hould be u se d for routine u se The se are so me of the g uid e line s and rul es -of-thumb that have been of va lue to me during my career. Perhap s thi s article will prompt other "s enior proces s engineers to s hare so me of the experience th ey have gained during their ca reers. We se nior s owe a lot to a profe ss ion that ha s rewarded us well, both per so nally and professionally 0 C h e mi ca l Engin ee ri ng Edu cation

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BOOK REVIEW: Introduction to Theoretical and Computational Fluid Dynamics Continued from page 29 emphasis of the book is strictly on fundamentals particu larly the general mathematical de scription of fluid motion s and the presentation of so lution s for important fundamental flow problems. The exposition is relatively a b stract; little reference is made to applications to experiments, or to ob se r va tion s of natural phenomena. In general sol ution s to posed problem s are obtained or outlined through exact ana lytical and numerical method s, primaril y via si ngularit y ap proache s or finite difference methods. This book contains a vast amount of detailed information, from the differential geometry of general surfaces in flow fields to the similarity sol ution s for Stok es flow near corners to the s ubtletie s of th e s tability problem for inviscid s hear flow. The book begin s with two excellent chapters on th e kine matic s of flow s; of particular note are explicit general for mula s for s urface mean curvature and a co ll ec tion of ve loc ity fields determined by various vor ticit y di s tribution s The next chapter introduce s s tre ss and the equation of motion ; nice features include a concise exposition of constitutive equations and a good di sc us s ion of vor ticit y transport; vor ticit y is a theme that receives a great deal of emphasis throughout the bo ok. A brie f c h apter on hydrostatics fol low s, including man y examples of the computation of static free s urface s hape s Curiously, mean c ur vat ur e is defined again, with no reference to Chapter 1. Chapter 5 presents many of the classical exact so lution s for viscous incompres s ible flow, including unidirectional flow s Jeffery-Hamel flow s tagnation point flows and flow s due to point so urce s. Flow at low Reynold s number s is the topic of Chapter 6 The primary emphasis i s on s ingularit y so lution s of Stoke s' equation, including a sketc h of boundar y -integral equation methods A fairly detailed exposition of lo ca l so lution s near corners is also given. Transient flow effects and the first effects of inertia are touched upon. Chapters 7 and 8 de scri be irrotational flow and boundary layer theory respectively For irrotational flow the ba sic results on force and torque exerted on a body in stea dy or time-dependent irrotational flow are de sc ribed. Several pages are devoted to the u se of conformal mapping for so lving the Laplace equation. The chapter on boundary layers provides good coverage of the classical material. As in other place s though the a uthor is so metime s overly terse here Chapter 9 is a very nice chapter on hydrodynamic stabil ity containing the ba sic results for s h ear flow free s urfac e, capillary, and centrifugal in s tabilitie s, though perhap s too brief regarding centrifugal in s tabilit y. Noteworthy is the di cussion of the concepts of absolute and convective instabilWinter 199 8 ity a nd their relationship It would have been nice however to see so me generic re s ult s about nonlinearity such as a brief di sc u ss ion of supercritica l and subcritical bifurc a tion. Chapters 10 and 11 focu s on the solution of inviscid flow problem s. Chapter 10 outlines the bound ary integral equa tion approach to the sol uti on of potential flow problem s while Chapter 11 d esc ribe s vo rtex motion in inviscid fluids with the goal of providing the framework for numerical so lution of vo rtex d y namic s problem s. Chapters 12 and 13 provide a whirlwind tour of finite-difference approaches to solvi ng convection-diffusion and incompressible flow prob lem s One attractive feature of thi s sectio n is the pre se ntation of th e modified differential e quation s associated with some of the approaches s ho wi n g for example, th at the instability of the FfCS sc heme for a hyperbolic equation is traceable to an effective negative numerical diffu s ivit y Finally, two con venient appendices contain ba s ic results in vector calculus and ba sic numerical method s There is clearly a great deal of material covered he re, and covered well. Nevertheless the breadth and depth of cover age ha s its cost. The text occasionally becomes an extended list of formulas so lution s, or method s This is fantastic as a reference; I ha ve u se d it repeatedly my se lf and referred parts of it to severa l graduate st udent s. It is not always ideal for teaching purpose though as the means by which so lutions are obtained is often given little motivation Detail s of solu tion procedure s are often not provided, and so metimes op portunities to impart phy s ical in sig ht are bypassed in favor of a terse, elegant, mathematical s tatement or argument. The level of mathematic al sop hi stica tion ass umed is at lea s t that of a first-year grad st udent in chemical engineer ing, preferably one who ha s already taken a n applied math class covering linear algebra and elementary partial differen tial equations. Becau se of the mathematical level of this book, the abstract point of view, and the so le emphasis on fundamental s, it is not appropriate as an undergraduate text for chemical engineering st udents Nevertheless, it is probabl y a text that any serio u s s tudent of fluid dy n a mic s would like to own and it wo uld provide a good t ex t for either an introductory or advanced graduate co urse in fluids depending on the topic s chosen. The lecturer will need to fill in man y of the moti va tion s and so lution detail s but this i s not a large price to pay for a text that outlines theoretical fluid dynamics as thoroughly as this one doe s In m y opinion this is a very important contribution to the textbook literature in fluid d y namic sa book I am happy to own and o ne th at I would hi g hl y recommend to anyone working in theoretical fluid dynami cs. 0 75

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.t.A.5-=1._l a b o r. a t o r .:, y _______ ) AN UNDERGRADUATE EXPERIMENT ON ADSORPTION SHAMSUZZAMAN F AROOQ National University of Singapore Singapore 119260 A dsorption separation has become a major unit op eration in the chemical proces s industry. Under graduate chemical engineering students at the National University of Singapore receive about six hours of lectures on adsorption fundamentals and applications as part of the course Separation Processes II offered in the third year of their study We have long felt there is a need for a suitable laboratory experiment that reinforces the basic design concepts Since reliable equilibrium and mass transfer data are central to the design of an adsorption separation process we have recently introduced an experiment in our third-year laboratory in which the students determine these parameters from break through measurements in an adsorption column During analysis of the breakthrough data, the students also develop a basic understanding of adsorption process dynamics EXPERIMENTAL APPARATU S The experimental apparatus for breakthrough measure ments schematically shown in Figure 1 consists of a col umn packed with the adsorbent under study and a host of pressure and flow controllers that control the operating pres sure and concentration of the ad s orbate in the feed respec tively. Further details on the experimental apparatus and the adsorbent used are given in Table 1. The adsorbate is nor mally mixed with an inert carrier. The effluent stream is analyzed u s ing a suitable detector to monitor the break76 S hamsu zza m an Far oo q received his BSc and MSc degrees in chemical engineering from BUET (Bangladesh) and his PhD from the University of New Brunswick (Canada) A faculty member in the Chemical Engineering Department at the National University of Singapore since 1991 his research interest is in the area of adsorption gas separation He is a coauthor of the book Pressure Swing Ad sorption (VCH 1994) Copy r ight ChE Di vision of ASE E 1 998 BPR AC Jacketed Adsorption column Bypass line OA Oxygen analyzer 9 Pressure gauge B PR Back pressure regulator ........ On-off valve RM Rotameter Mass flow controller CR Chart recorder Figure 1. S c hemati c diagram of the breakthrough apparatus. Furth e r d e tails ar e g iv e n in Table 1. through of the adsorbate. The desorption response is mea sured by withdrawing the flow of adsorbate from the feed after the column has been s aturated. THEORY A typical breakthrough response from a clean bed to a step change in adsorbate concentration in the feed is shown in Figure 2, where c is the concentration at any time, t, and c 0 is the constant feed concentration When the adsorbate concen tration in the effluent equals that in the feed, it indicates that the bed has been saturated Material balance over a saturated bed gives mean residence time t = (shaded area in Figure 2) ~ ( ) ( ) c L l eq 0 =f 1 dt=l+--c 0 v 0 e c 0 0 where L length of packed bed v O interstitial feed velocity Ch e mi c al Engin ee ring Education

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E bed voidage q 0 eq uilibrium adsor b ed amo unt corresponding to feed con centration, c 0 A typi ca l favorable equilibrium isotherm is s h ow n in Figure 3. H e nry 's constant will b e mea s ur ed in thi s s tud y, which r eq uire s that the experiments are co ndu cted in th e line ar (low co ncentr a tion ) range of the isotherm. Ratio of H enry's co n s tant s of two a d sorba bl e components i s the primary mea s ure of th eir se parability. It is important to note th at h ere Henry 's co n s tant i s dimen s ionl ess, s in ce it ha s be en ex pr essed as concentration ratios. H enry's constant follows the Arrheniu s Law of temperature d e pend e nce The following equation is app li ca bl e for di men s ionle ss H e nr y's co n s tant: w h ere K 0 pre-exponential factor R 8 gas co n s t a nt in h ea t unit s T temperature s in abso lut e unit s A sem ilo gar ithmic plot of K vs. lff s h o uld give a straig ht line w ith -t.U 0 / R g as the s lop e a nd K 0 as the intercept. The change of internal energy du e to adsor pti o n t.U 0 i s related --le 0 t ---------..... __ .... I ... .,.. 1 Adsorption column .,.. Feed ...._ _________ __,Effluent v 0 cm/s c moles /cc c 0 moles/cc Figure 2. A typical breakthrough response for a step c hang e in feed concentratio n Adsorbed phase concentration q ( moles / cc ) slope=q J c 0 Flu i d phase concentration c { moles / cc) Lt q 0 = Dimensionless c .. 0 c 0 Henry's constant, K Figure 3. Favorab l e adsorption i so th e rm. TABLE 1 Details of the Experimental Apparatus Shown in Figure 1. Mass Flow Contro ll ers H el ium lin e Oxygen lin e J acketed Adsorption Co lumn (s tainl ess s t eel ) L e n g th : 40 cm Inner tub e: I 1/2 inch; sc h e dul e 40 Outer t ube : 2 1/2 inch; sc h ed ul e: 40 Temperature R eg ul a t ed Water Circulation Oxygen Analyzer Chart R ecor d e r Pr ess ure Gauge On-Off Va l ves Plumbin g Stain l ess s t ee l tub e Male co nn ec t o r U nion Un i on e lb ow Adsorbe nt Wint e r 1998 Ma nufactur e r Brooks J&W Fabricated in th e wo rk s h o p Poly Science SERVOMEX Rik ade nki W IK A Whitey Swagelok Swagelok Swagelok Model/Part No Rang e/Size 5850E ( Co ntr o ll er ) 0 -10 1/m 0 1 51 E (d i s pl ay) 200-2002 built-in s pan adj u st m ent from I cc/ m t o 1000 cc/m Pr ess ur e te s t ed at 200 psi 9 1 0 1 I 0 95 C ; 7 or 15 1/m 572 Output : 0-1 V for 0-100 % oxyge n R -6 1A I 00 m V f ull -scale se ttin g was u sed 0-I00psi SS-41S2 1 /8 inch 1/8 inch SS-200-1-2 1 /8 inch SS-200-6 1/ 8 inch SS-200-9 1 /8 inch Carbo n mol ec ular s ieve: Shira s i g i MSG 3A fro m cocon ut s h e U Provid e d b y a l ocal pharmaceuti cal co mpany from th e s uppl y for their PSA nitrogen unit. 77

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to the limiting heat of adsorption ,: '.U 0 = LiH 0 + R g T. For cal culating LiH 0 from LiU 0 the average temperature of the experimental range is used. On the other hand, if the Henry 's constant is expressed in terms of adsorbate pressure (we denote it by K'=K/R'T, where R is the gas constant in pressure units) then its temperature dependence may be directly related to the heat of adsorption -~ H o K -K' e R g T 0 The desorption breakthrough is obtained when a saturated bed is purged with inert. In the linear (and very low concen tration) range of the isotherm, the adsorption and desorption profiles obtained at the same velocity are symmetric. The system of equations that describe the dynamic re sponse of an adsorption column is given in Table 2 Analyti cal solution to the set of equations is given by Lapidus and Amundson[l l in the form of complicated infinite integral. In this study, numerical solution by the method of orthogonal collocation is used (The collocation form of the model equations may be obtained from the author upon request.) The input parameters for the model are Column length L given (40 cm) Bed voidage, e given (0 35) Column radius R given (2.05 cm) Adsorbent particle radius R P given (0.1 cm) Interstitial feed velocity v O = u 0 / e u 0 is calculated from the flow rate measured during experiment (emfs) Equilibrium constant, K obtained from the break through curve Peclet number, Pe determined from available correlation Mass transfer parameter k to be determined by matching the experimental breakthrough curve Pe= v o L DL where DL = 0 7 Dm + v o Rp The molecular diffusivity of the adsorbate in the carrier is Dm(cm 2 /s) and may be calculated from Chapman-Enskog 's equation. l 2 1 All known commercial adsorbents offer external film macropore and micropore resistance s to the transport of the adsorbate molecules from the bulk phase to the inte rior adsorption sites. A linear driving force (LDF) rate model is used here to represent the transport across these resis tances, k is the overall LDF rate constant. The LDF model approximates a distributed resistance to be confined in an equivalent thin zone. The individual resistances linearly add up to give the overall LDF resistance 1/k: I R P K R 2 K r 2 + _P_ -t_ c k 3 k r 15 D e 15 D C ex t e rnal ma c rop o r e mi c rop o r e film r es i sta n ce r es i s t a n ce r es ist a n ce The LDF model may be viewed as a lumped parameter model with the luxury of relating the overall constant to the more fundamental parameters that characterize the constitu tive transport processes. The film mass transfer coefficient kr, may be calculated from the following correlation pro posed by Wakao and Funazkri :l3 1 Sh= 2.0 + 1.1 Re 06 Sc 1 13 where Sh Sherwood number= 2 krR/D m Re Reynold 's number= ( 2 Rp ) pu 0 / Sc Schmidt number = / pD m TABLE2 Mode l Assumptions and Equations ( In th e followin g equ a tion s Y i s the mole fra c tion of the ad s orbable c omponent in th e gas ph ase; z i s the axial di s tance ; tis the time; Pi s th e total system pressure ; and q i s the tot a l adsorbed am o unt. Other s ymbol s a r e d e fined in th e t ex t. ) Assumptions Fluid pha se component material balance I s othermal D L -+ v 0 -+ +--= O cl z 2 clz ci t e P ci t Continuity condition The flow pattern i s de sc ribed by th e axial P f (z} f ( t } di s p e rs e d plug flow Flow boundar y c ondition s Th e friction a l pre ss ur e drop i s negligible cl YI ( I I ) ~: I z= L =O DL=-vo y Y ; Ideal ga s l a w holds clz z= O z=Oz= O + Mass tr a n s fer b e tween fluid a nd particle The mass transf e r rates are r e presented by clq k(* -) linear driving force rate e x pre s sions q q cit Equilibrium isotherm Linear i s otherm =K c = K c 0 Y q 78 Ch e mical Engin ee ring Edu c ation

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p, density and viscosity respectively. The above correlation is particularly recommended as it wa s able to reconcile experimental data from a large number of sources. PDP D e= -'twhere 1/D p = 1/D m + 1/D K The Knudson diffusivity D K (cm 2 /s) becomes important when collision of the diffusing species with the pore walls becomes significant in comparison to the intermolecular col lision Poiseuille flow and surface diffu s ion are two other parallel contributions to tran sport in the macropore s. Poi seuille flow is n eglected since the pre ss ure range in which it becomes important will not be encou nt ered in thi s s tud y. Surface diffusion occurs through the adsorbed layer on the macropore walls Thi s is commonly found to be impor tant in homogeneous adsorbents, s uch as activated carbon, activated alumina si li ca gel, etc For composite adsorbents, such as carbon molecular sieve and pelleted zeolites, the adsorption capacity i s mainl y in the micropore s; the macropore walls are practicall y inert and the condition for s urface diffusion to occur does not arise. Therefore s urface diffusion is also ne glected, since we will s tud y the adsorp tion and diffusion of oxygen in carbon molecular s ie ve Of course in the chosen sys tem, both molecular and Knud so n diffu sion are much fa s ter than the micropore diffusion and may be neglected as well Neverthele ss, the se terms are di sc u ssed further in view of their wider conceptual impor tance as mechanism s of transport in porou s media in general. Knudsen diffu s i v it y is given b y where I; pore rad iu s (c m ) T temperature ( in absolute unit s) M molecular weight of th e adsorbate 't absorbent parti c le vo id age a nd t or tu osity respectively. A typical value for 't /P i s approximately 10. Therefore, in the expre ss ion for ma ss transfer parameter the micropore diffusional time constant, De/ r ; i s the only unknown that i s determined by matching the model solution for a breakthrough with the experimental re s ponse. Micropore diffusion i s an activated proce ss and follows Arrhenius-type temperatur e dependence A semilogarithmic plot of D e vs. 1/f known in the literature as the Eyring plot will give the activation energy E, from the slope and the pre-exponential factor, D c 0 as the intercept. For some adsorbent s, suc h as carbon molecular sieve, r e Winter 1998 cannot be measured explicitly. In s uch cases, D e / r; i s plot ted aga in s t 1/T which yields D c o Ir ; as an intercept. EXPERIMENTAL PROCEDURE The s tud y of adsorption and diffu sio n of oxygen in a carbon mol ec ular s ie ve i s c ho se n as the mod e l sys tem here Helium i s u se d as th e in ert carrier. The following se t of in str uction s is pro vi ded to guide the s tudent s throu gh the vario u s s tep s of the experiment. Th e oxygen a nal yze r r es p o n se s hould be c heck e d for O a nd 100 % oxyge n Th e o utput range i s 0-1 Vandis lin ear. The calibratio n c ur ve for the mass flow controller u se d for the carrier gas i s provided The total mi xed fl ow ca n b e easily det erm in e d by a n alyzi n g it s oxyge n co nt e nt. It i s s u gges t e d th a t the interstitial fee d ve lo c it y in the column a nd oxyge n co n ce ntrati o n in the fee d are m a int a ined betw ee n 5 a nd 10 emfs and between 2 a nd 4 %, r es p ec tiv e l y. The adsorption column s hould b e b y p asse d during flow and co n ce nt ra ti o n adjustments. Th e syste m ga u ge pr ess ure s hould not exceed 0.5 b ar. The effl u e nt i s a nal yze d u s in g th e oxygen a nal yze r. A c hart recorder i s u se d to record the a naly ze r s ignal. The c h art s p eed a nd range setting must e n s ur e s uffi c ient resolu tion of th e o utput s i g nal from the oxyge n a nal yzer as a fun c ti o n o f tim e Water ( from a temperature-regu l a t e d t a nk ) i s circu l a ted through th e j acke t of the column at th e d es ired temp e rature. The m eas ur e m e nt s s h o uld b e co nduct e d at thre e tempe ra tures in the range of 30 t o 50 C. The choice of temperat ur es s hould be eve nl y s p aced and a t l eas t 45 minut es mu st be a ll owe d for the bed to attain thermal e quilibrium wi th th e circ ul a tin g water. It is a l so recommended to move from l ow to hi g h temperature. The b e d s h o uld b e pur ge d wit h h e lium until th e O V ba se line i s attained. This e n s ur es a c l ea n b ed wit h r es p ec t to oxygen. Intr od u ct ion of the oxyge n step in the feed a nd switc hin g th e c hart on at th e d es ir e d s p ee d mu s t occur s imult a neousl y It is esse nti a l th at th e br eak throu g h curves be m e asured until co mpl e ti o n It is ne cessa r y t o record the desorption br eakt hrou g h curve for at l east one temperature in order to check line ari t y of th e i so th erm at the c ho sen co n ce ntrati o n l eve l. Oth e r than the formal de sorp ti o n run the b e d is re ge nerated b y pur g in g w ith helium a nd in c r ease in temperature. The adsorption breakthrough m eas ur e ment i s repeated w hen the b ed ha s been co mpl e t e l y r ege n era ted and ha s attained the new temperatur e. RESULTS AND DISCUSSION The s tud e nt s are required to includ e the following resu lt s in their report on th e ex p e riment: 1. Plot of c/c 0 vs. tim e for adsorption and ( l-c/c 0 ) vs time for de so rption on the sa m e graph in order to check th e sy mm e tr y. 79

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2 K 0 ti.U 0 a nd ti.H 0 va l ue s from the se milogarithmic plot of K vs. l!f. 3 D ea I r z and E values from the se mi l ogarithmic plot of D e Ir ; vs. l!f Typical plots are s h own in Figures 4 thro u gh 6 The param eter values determined from these p l ots are also s hown in the respective figure s. The equilibrium constant is obtained di rectly from the mean re s idence time calculated by integrat ing the breakthrough curves, as discussed ear l ier. The mass transfer parameter is obtained by matching the breakthrough profile s with the model solution. The effect of the mass transfer coefficient on the model solution is shown in Figure 7 It i s clear that t h e model so l ution i s quite sensitive to the value of k The s tudent s are reminded that several numerical techniques are ava ilable to determine the best-fit va l ue s But s tudents carry out all the nece ssa ry computations and calculations in the laboratory and, in view of the limited laboratory time, they are allowed to u se eye estimation to decide on the be s t fit. While using the above method to measure D e / r ;, it is extremely important to remember that all the di s per s ive ef fects in an adsorption column (namely, axial di s per s ion external film, and intraparticle diffu s ional resistances) that are identified in the mathematical model have similar effects on the s hape of the breakthrough curve. Therefore these effects cannot be separated from a s ing l e experiment. More over, s ince the resistances are linearly additive, t h ere i s a l ways a ri s k of mi s interpreting the results. Hence, there i s an inherent need to alway s ensure that the rate parameter under investigation is indeed the controlling factor of the proces s dynamic s Reliable accounting of other effects i s also nece ssary when they are not completely negligible Estimation of external film and macropore re s i s tance s are more reliable th a n prediction of axial disper s ion Maldi s tribution of gas flow and extra-column effects con tribute to additional axial dispersion unpredictable by pub li s hed correlations. Agglomeration of s mall particle s may also re s ult in excessive axial disper s ion (see reference 3 for a comprehensive di sc u ss ion). All these pos s ibilitie s were taken into account while designing the experimental s ystem used here. In order to ensure proper flow di stri bution the column size was chosen to sat i sfy the recommended column-to particle diameter ratio. Furthermor e, 1/8-inch tube s and fit ting were used to minimize extra-column mixing effects In spite of all these precautions, experimental verification is recommended to confirm that the associated di s per s ive ef fect s are correctly estimated Although the available laboratory time is not s ufficient to include s uch supporting experiments, the students do not remain ignorant on these matters. In addition to writing a general discussion on the findings they are also asked to s ugge s t an experiment to prove that the present sys tem is micropore-diffusion controlled and to comment on the effect 80 J 0 8 6 e 6 y 6 0 6 6 o 0.4 1 Adso r p t io d 10.2 o De s orp ti o n (,.) 0 0 50 1 00 150 200 250 300 Time (s) Fig u re 4 Symmetry of the adsorption and d esorp tion breakthrough c urv es in th e lin ear range of the eq uilibrium isotherm 100 T"""----------------, 10 6 U 0 = 3 5 kcal/mo !; 6 H 0 = 4 1 kcal/mo! 1 +---...... -----..---------1 0 003 0.0031 0.0033 0 0034 Figure 5. T e mperature d epe nd e n ce of H e nr y s consta nt (oxygen in a c arbon mol ec ular sieve) showing that it follows Arrhenius Law. 1 00E 01 ,-----------------. E = 4 1 2 kcal/mo! U) ,; : 1 00E-02 ... 0 C 1. 00E-0 3 +---------,.----...-------1 0.003 0 0031 0.0032 0.0033 0.0034 1/T (K 1 ) Fig u re 6 E yri n g plot showing temperature dependence of micropore diffusivity for the diffusion of oxygen in a carbon molecular sieve. 1 ,------::::::::::::s:=~~ --, 0 8 .!:!..6 u 0.4 0.2 -k = 0 10 (/s) k = 0 .2 0 (/ s ) k = 0 05 (/s ) E ~ x p t _~ 0 ~.-:;;.~--~--,----,.----~--I 0 50 1 00 150 Time (s ) 200 250 300 F igur e 7. Effect of WF mass transfer coefficient (k) on the model solution. Chemical Engineering Education

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of macropore size and operating pressure on the macropore resistance. These questions guide their thoughts to the fol lowing important points : For a micropore-controlled system, a reduction in the macroparticle s ize should not affect the ma ss transfer kinetics. Hence when the k value remains unaffected by a change in the particle size, it serves as clear proof that the axial di s per s ion and macropore re s istance are practically negligible. On the other hand a variation in values est imated from experimental runs with different particle s ize and/or at different velocities will indicate that the seco ndar y re sistances are not negligible and their contributions have not been properly estimated. The importance of Knudsen diffusivity depend s on the effective macropore size and is independent of pressure, whereas mo lecular diffusivity is inversely proportional to pressure and may affect the overall transport rate at a higher pres s ure. CONCLUSIONS This laboratory exercise introduces the students to the calculations of equilibrium and kinetic parameters for an adsorption separation process. The use of a dynamic model for the extraction of the mass transfer parameter provides a useful visualization of the role of this parameter on process performance. The simulation model can also be effectively used to illustrate in detail the numerical so lution of a system of coupled partial differential equations. The consistency of results obtained by different groups is encouraging. Equilib rium capacity and mass transfer resistance of the chosen system are well suited for completing the required number of runs and necessary computations in one standard labora tory session of six hours. REFERENCES 1. Lapidus L. and N.R. Amundson, J of Phy. Chem., 56, 984 ( 1952 ) 2. Sherwood, T.K. R.L. Pigford and C.R. Wilke, Mass Trans fer, McGraw-Hill, New York NY; Chap. 2 3. Ruthven D.M., Principles of Adsorption and Adsorption Process es, Wiley Interscience New York, NY, Chap. 7 ( 1984 ) 0 BOO K REVIEW: Batch Distillation Continued from page 13. Example 1 .2 are easily misinterpreted. And there is a tech nical mistake in the calculation of the heat to the reboiler in Eqs. (2.13) and (2.17). The author ignores the energy re quired to vaporize the distillate product in the reboiler. Equation 2.13 should be QR =A.(R+l)D. The graduate-level material starts in Chapter 3, Column Dynamics," which derives the unsteady mass and energy balances. Then error, stability, and a summary of numerical integration techniques are presented. The need for an inte gration technique capable of handling stiff equations is clearly illustrated in Example 3.1. The chapter is completed Wint e r 1998 with sectio n s on s tart-up and approximate models. There are so me parts that will confuse students. For example, the numbering of stages in Figure 3.1 doe s not agree with the equations, and derivation of Eq. (3.44) requires assump tion s not mentioned in the text. The author is clearly an expert on the application of shortcut (Fenske-Underwood-Gilliland) methods to batch distillation. Reader s are told to be careful in choosing the appropriate value for the light key and heavy key for s uc cessful u se of thi s method ," but how to be careful i s not explained. This and other small mysterie s will cause confu s ion The modified shortcut method developed next re quires lumping a number of plate s into compartments. Other than comparison with an exact solution, no guid ance is given on how to select the number of plates in each compartment. The last sec tion on the hierarchy of model s in the si mulator will be very helpful to students using the simulator. Chapter 5, Optimization ," describes objective functions, degree of freedom analysis, feasibility, and the general frame work of solution methods. This chapter is quite general and would benefit greatly from numerical examples. Chapter 6 on optimal control problems builds on Chapter 5. This chapter would also benefit from numerical examples in addition to the derivation examples. The last chapter analyzes azeotropic systems and col umns with a middle vessel. Since most students will be unfamiliar with the analysis of steady s tate azeotropic dis tillation, more details on re si due curve map s and synthesis of batch di s tillation systems would be welcome. The short cut method i s extended to binary azeotropic systems and s imple ternary syste m s. Extension to more complicated ter nary azeotropic systems would be welcome. The index appears to be quite well done. An author index would be appreciated. The reference lists at the end of each chapter appear to include all the important historical and recent papers The nomenclature list is quite complete, and the tables that summarize the equations after each theoreti cal development are helpful. The type is easy to read and there appear to be few typographical errors. Unfortunately, the figures are not of professional quality and are difficult to interpret. Many of the figures have multiple curves that are not labeled. When two theories are compared on the same figure, the reader need s to guess which is which. The curves are not smooth and it is often unclear if the wiggles are real or due to the plotting routine. Every chemical engineering department should obtain a copy for their library's reserve section. Chapters l and 2 will be helpful as a reference for undergraduates doing laboratory or design projects on binary batch distillation. The remainder of the book will help graduate students and professors who occasionally encounter multicomponent batch distillation problem s. 0 81

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.t3llillllijllllliil-c _l_a_s_s_~_o_o_m _________ ) COMBUSTION SYNTHESIS AND MATERIALS PROCESSING Student Exercises DANIELE. ROSNER Yale University New Haven, CT 06520-8286 The student exerc is es below are representative of those developed for the Yale gradua t e course, "Comb ustion for Synthesis and Materials Processing," described in the fall issue of CEE (page 228). Among other purposes, they demon strate that rather si mpl e but quit e rational ca l c ulation s can be made to estimate approximately ho w large a combustion r eac tor must be in order to produce, say, a metric ton of hi g va lu e product every hour. Such preliminary design ca l cula tions are prudent first steps before conside rin g more detailed follow-on ca l culat ion s. Th ey also develop a young engineer's intuition and provide inter esting CS/MP exam pl es of the im portant role of the ChE co re s ubj ects: c h emical thermod y namics h o mo ge n eo us/h ete rog eneous che mi cal kinetics, trans port ph eno m ena, separation pr ocesses, and chemica l r eac ti o n e n ginee ring All notation is that of the author ( R ef 7, fo e c it.). Educators interested in further CS/MP exerc ises ca n co nta c t the aut hor at Yale University or e l ect roni ca ll y v ia rosner@htcre.eng.yale.edu EXERCISE] Consider the combustor volume required for sulfur spray combustion at l.4 atm at the S(l) feed rate of 50 t/d. a) If efficient S(l) spray combustors can be operated at volumetric chemical energy release rates < ci ;he m >, of about 2 MW/m 3, then what volume should be provided for a 50 t/d unit? b) How does this average volumetric chemical energy re lease rate compare to that in a small oil burner for home heating ? Or a gas turbine engine combustor (a t 3 GW/m 3 at 30 atm) when corrected down to 1.4 atm? (cf. Fig. l la c cit.) c) If the amount of excess air used is that required for the combustion product mixture to have a temperature near 1400 K then what will be the mean residence time (ms) in such a sulfur burner? d) Estimate the time required to heat up a 100 m S(I) droplet from 415 K to 700 Kif the liquid heat capacity i s Copyright ChE Di uision of ASEE 1997 82 estimated as 0 .2 8 cal/g-K and the density is 1.8 g / cm 3 e) Estimate the time required to burn a 100 m S(I) droplet at approximately 700 K if the latent heat of S(l) vapor ization is 0.42 kcal/g and the ambient conditions are (1)02 ,oo = 0 232, T 00 = 350K f) What phenomena would lengthen the time required to completely convert all S(]) droplets beyond yo ur esti mates from pruts d and "e" above? g) Is the combustor volume provided in part (a) likely to be adequate in thi s case? What would be the next steps you would recommend before cutting metal "? EXERCISE2 a) Does the s uccessful growth of diamond films from gas mixtures containing CH ig) and H(g) at 1 atm on 1200 K surfaces shake your confidence in the value of thermo dynamic principles to judge the feasibility of chemical syntheses, generally? (See reference 1 below.) Does combustion synthesis of diamond films under these con dition s violate the second law of thermodynamics ? Dis cuss the broader implications of thi s recent discovery. b) Approximately 20 m (volume equivalent) diameter dia mond crystallites (grains) are grown from rich C 2 H/O 2 flames impinging on 1200 K solid targets at p=l atm. How many carats are these ? (I carat = 200 mg) How do they compare to the 30-mg diamonds synthesized (si nce 1954 ) by GE Corporation at p = 30 kbar T = 2200 K ? To get a phy sica l feel for this pres s ure convert to the units : metric ton s (fo rce)/ (mm)2. c) Consider the phase equilibrium C(graphite) <=> C(diamond) in the single element system: carbon, from the viewpoint of the Gibbs phase rule. How many state variab le s are needed to define this system? d) We know that C 2 H i(g) can be commercially synthesized from the pyrolysis of methane CH/g) via a partial combustion process at acceptable yields. It i s interesting that diamond film growth is found to be possible via the Chemical Engine e ring Edu cation

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fuel-rich combustion of either C 2 H i(g) or CHig ), but the maximum attainable growth rates (ofte n expressed in microns/h ) have been found to be larg er for acetylene by factors of nearly 20. Considering the overall economics, how would you decide on which carbonaceous fuel to use if your goal is to grow commerically interesting diamond films? EXERCISE3 Consider the preliminary de s ign (sizing) of a 25 t/d acety l ene synthesis reactor (near-plug-flow, axi-symmetric) to operate at near-atmospheric pressure. Ba se d on preliminary laboratory data, it appears that the partial oxidation of pre heated methane using oxygen, followed by approximately I ms. cracking at about 1800 K (before a water-spray quench to 350 K) le ads to a product stream with about 8 mole pct. acetylene vapor and unavoidably produces solid carbon soot at the rate of about 50 kg/t C 2 H 2 Preheating both (unmixed) reagents to about 900 K i s considered the highest safe temperature choice to avoid autoignition upstream of the burner block/flame-holder. Make a self-consistent pre liminary choice of all essential dimen s ion s in the course of answering the following specific questions. a) If the overall stoichiometry of the partial combustion of methane is CH 4 (g) + ( l/2)O i(g) CO(g) + 2 H i(g), then estimate the individual O i(g) and CH ig) mass flow rates (kg/s). b) Before turning to the turbulent jet mixing-diffuser sec tion, estimate the required dimension s of a stable burner/ flame-holder, including the channel diameters, number of channels, and open area fraction. Also select the down stream "c racking chamber" dimensions. For these pur poses u se the following tentative estimates: flame s peed Su (rich CH/O 2 ) = 28 emfs at 298 K I atm; d R n S/d Rn T" = 1.86 for methane/air; (L/U) crack in g s ectio n = 1 ms. What factors should govern the channel ( hole ) lengths ? (cf. Fig. 4, Lo e cit .) c) Is the heat of partial combustion [CHig) + ( 1/2) O i(g) CO(g) + 2 H i(g) ] sufficient to raise the preheated mixture of methane and oxygen from 900 K to the crack ing temperature of 1800 K without the addition of auxil iary oxygen at the burner/flame-holder location? Tenta tively neglect the possibly appreciable heat lo sses to a (water-cooled?) burner/flame holder. d) Estimate the heating value of the so lid carbon removed from this unit if it could be recovered and burned to CO i(g) e) What factors dictate the quench water-flow-rate require ment? What spray velocities and drop sizes s hould be used? (cf. Fig. 4 Loe cit.) O How would your choices of dimensions change if you Winter 1998 opted for a syn the s i s reactor operating at 5 atm? For this purpose, note that the effective order of the me t hane oxidation corresponding to pre vio u s ly observed Su(p) data for combustion with air i s about 1.4. g) Returning to the turbulent jet mixing-diffuser section can you provide a rough estimate (bound?) of the required length the transver se dimen s ion s (diameters) for the 1 atrn device ? For all of the above items spell out and defend all further assumptions you introduce. EXERCISE4 The surface of one C 60 molecule contains 20 hexagons and 12 pentagons. Based on the presumption that the C-C bond di s tance in C 60 is clo se to that in the graphite crystal (1.42 A) estimate a) The surface area of one C 60 molecule. b) The effective diameter of one C 60 molecule. c) Use the result in part b to estimate the Fick molecular diffusion coefficient of C 60 with respect to CO /g) at 2100 Kand 100 Torr (v ia hard-sphere kinetic theory) d) Compare the specific surface area (m 2 /g) of C 60 to that of commercial activated carbon as well as flame soot (con taining non-porous primary particles of30 nm diameter). What conclusion(s) do you draw from this ? e) Extrapolating from the information provided in the re cent review of Howard (1992), suppose that C 60 could be produced in a 100 Torr benzene/O 2 combustor at a yield of 0.5 pct. of the fuel carbon. If the burner C/O ratio is about 0 .9, use the present costs of benzene ($/kg) and 0 2 ($ /std m 3 ) to 1) Estimate the fuel cost per kg of C 60 produced and 0 2 cost per kg of C 60 produced. 2) Estimate the pumping cost per kg of C 60 produced. 3) Compare the s um of these costs to the actual present cost per kg. of C 60 4) Is a combustion process currently used (by Aldrich Hoech s t AG . ) to produce research quantities of C 60 ? What intrinsic advantages would a combustion synthesis process have over rival (electric spark a nd laser pulse/graphite feed) methods ? 0 Use the reported equilibrium vapor pressure of crystal line C 60 (s) to estimate the frost point temperature of C 60 in the abovementioned synthesis flame. I s a paitial de s ublimation se paration method feasible for harvesting C 60 in thi s case? REFERENCES 1. Dodge B.F. "Application of Thermodynamics to Chemical Reaction Equilibria ," Trans Am e r. Inst. Chem Eng. 34 529 ( 1938 ) 0 83

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t.a_5_3._c_u_r r i c u l_u_m ___ __ __ ) JUSTA COMMUNICATIONS COURSE? Or Training for Life after the University Gumo BENDRICH University of New Brunswick Fredericton, New Brunswick Canada E3B 5A3 T oday, many chemical engineering curricula include courses in strength of materials, electronics, heat and mass transfer, reactor engineering, plant design eco nomic s, communication skills, etc. Competence and techni cal expertise alone, however, will not guarantee graduates (or, as a matter of fact, anyone) a job in today's economy. We should not only teach our students the necessary tools to enable them to survive in a work environment but we should also assist them in their transition from the university to industry. While there are career placement services on al most every university, their success in helping students find suitable employment after graduation is usually limited Having noted these difficulties in the past I felt a need to become more actively involved in assisting students to find employment. Our students are now being given an early opportunity, as part of a two-credit-hour course in "Commu nications and Information Systems ,"r 11 to learn more about technical report writing, oral presentation skills, computer applications, and life after the university Many publications have been written on the subject of developing good communication skills.r 2 31 This paper dis cusses the techniques used to teach students the principles of critical thinking, communication skills, and up-to-date com84 Gui do Bend rich joined the Department of Chemical Engineering at the University of New Brunswick after spending some nineteen years in various industrial settings throughout the world He obtained a PhD from McMaster Uni versity in 1992. His teaching and research inter ests are in industrial plant design cost estima tion plastics processing developing communi cation skills and education. Copyright ChE Di vision of ASEE 1998 TA B LE 1 Course Objectives (Short Version) You will brin g your own int erests and we sha ll discuss how they may be inc orpora ted into th e ChE 1014 co ur se. We hav e an academ i c re s ponsibility also to ensure that we aim for certain l ea rnin g objectives and, for this course tho se ob jective s are as follows: I D eve lopment of co mmunic at ion ski ll s through oral a nd written presentations. 2. Familiarization with current information technolo gies. Learni11g Objectives Learning at this stage of your education mean s the development of c ritic a l skil l s. In this co ur se, therefore yo u will be articulating facts co n ce pt s, principles, and rul es; problem so lving in real life s ituation s; u s ing effective communication skills; interacting productivel y in small and large group setti ng s; and enjoying yo ur se lf too! The Tools We s hall select practical examples to illustrate the principle s of critical thinking, communication ski ll s, and up-to-dat e comp uter technologies. The main part of the course shall be centered around the area of "Job Huntin g The following steps will not only describe the course str ucture in more detail but also present a possible application of th e material studied to a real-life situatio n. Career Ass ess ment the most c ritical phase in th e whole process We s hall di sc u ss the various aspects in the area of Critical Thinking Skills and how we can make good use of it at hom e, in sc hool or in a work environment. Decision Makin g all about choices In order to make e du ca t ed decisions o n e mu st have access to pertinent information. We shal l exp l ore different ways of o btainin g th e necessary information, e.g. librarie s, databases an d the Internet. The R es um e-a very effect i ve marketing tool The development of a g reat resume require s of computer t ec hnology. We s h a ll familiarize ourselves with the use of va riou s computer applications s uch as word processors, databases, etc. The Job Market You will pr ese nt in a IO-minute oral presentation some detailed information o n the industry of your int erest. We sha ll exp lor e th e u se of overhead tran s paren cies and co mputer-b ase d presentation techniques. In additio n you will be given an opportunity to s ummariz e yo ur findings in the form of a technical report. The Cover Letter The writing of cove r letter s, i .e letter s of transmittal is a n important p art in an engineer 's working life We s hall team a bout the various sty l es of cover letters The Int erview We s hall reinforc e o ur critical thinking ski ll s, learn about active listening observe and diagnose verbal and nonv e rb a l messages, and, mo s t importantly learn how to handle problem (stress) si tu atio n s Practice interviews will assist in refining these ski ll s. The Tale of a Su ccess Story At this stage, th e course is comi n g t o an end You have n ot o nl y learned about various computer applications, lit era tur e s earches oral and written pre se ntation s, and critical thinkin g sk ill s but mor e importantly yo u have had an opportunity to apply of the se techniques to different s itu atio n s in yo ur daily life Chemical Engineering Education

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TABLE2 Six Thinking Hats ( Reference: Edward deBono 1 61 ) Color of Hat Characteristics White Facts fi g ur es, object i ve material .. R ed Feelin gs, emotions intuition Black Lo g ical neg a ti ve arguments, .. Yellow P oss ibiliti es, opportunitie s, ... Green Creati ve n ew id eas, . Blue Ma s ter c ontrol for th e thinkin g pro cess Questions What information do I need t o make a decision? H ow ca n thi s information b e o btain ed? Ho w d o I feel about it ? Wh a t doe s m y inn er vo i ce" say a bout thi s? What are tb e ri sks? What does Murph y's La w" say a bout thi s? What are th e a dv a ntage s? What i s the be s t-c ase sce nari o? Can I come up w ith a more innovative approach? Summari ze results Re v i ew of re s ult s Name: ____________ Date : _--'---'-TABLE3 Suggested Career-Related Topics to Think About Topic R es ult s from the Six Thi11ki11g Ha ts Intellectual c h a ll enge Meaningful work Opportunity to learn new thing s Sen se of ac hi eveme nt Creativit y Interpersonal relation s hip s Salary Benefits Job Security Social Status Promotions Opportunity to travel Per so nal growth Independence Fast-paced Future power Variety of t asks Exciting, stimulating I Study th e t en most impor t ant value items ; do yo u n otice any specific patterns ? 2 D eve lop an I can d o" li st b y identifying some actions that will integrate yo ur expectations in e du cat i o nal s trat egy. Name __________ Date _______ Winter 1998 puter technologies b ase d on real-world applications s uch as "fi nding the right job. The course objectives are out lined in Table 1 The following steps highlight the techniques u sed to achieve these goal s : Critical Thinking Skills S R. Covey 141 discusses the four uniqu e hum an endowments of imagi nation, conscience independent will, and se lf-awarene ss. Imagination as defined by Covey is the ability to envision to see the potential to create with o ur minds what we cannot see at the present with our eyes." Thi s a bil ity does not come naturally but it ca n b e learned The Critical Thinking Skills segment of this co ur se provides the st udent s wit h insight in the deci sio n-makin g proce ss. Some of the techniques di sc u ssed in detail are ones de s cribed b y Covey / 41 deBono / 61 and Butl er and Hop eY 1 These techniques aid s tudents in discovering mor e about themselves In o ne exercise based on deBono 's approach each class participant i s asked to imagine s ix colored hat s. Each h at represents a role one 's mind plays in th e critica l thinking process. By switching from one hat to another as one thinks about a topic the learn er i s forced to look at the topic from a vari ety of perspectives Y 1 For the exercise the st udent s s tart with six s heet s of paper-one for each hat. They se lect a topic or problem th at the y would like to think about or work on Each partici pant decide s which of the hat s would b e good to s tart with and then works hi s /h er way throu g h all six, wr iting down note s on the thoughts th a t come to th em with each hat. Table 2 identi fies the six hat s, their characteristics and so m e of th e question s one s hould ask with each oneY 1 Th e students may think of other question s as well. If the learner has worked a problem through all six hat s and ha s written down at lea s t three point s for each he/ s h e will know that a ll the major point s in the critical thinking proce ss were covered. Table 3 pre se nt s some s ug85

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gested career-related heading s that may be used to explore the critical thinking proce ss. This and similar exercises will not only help the students learn more about them se lves but they can also aid the st udent s in identifying their long-term career objectives. A sig nificant increase in se lf awareness can be observed over the course of the term. Computer Applications In this part of the course various computer app li ca tions, such as word processors, sp readsheet s, data ba ses, e-mail and Internet tools, are introduced to the students. Guidance is provided through the use of slides handout s, and extensive hands-on exercises. Obtaining Information Information Technology is the buzzword of the 90s and in that vein, an in-depth summary called 'T he Retrieval of Information" is presented to the s tudent s. Among the topics discussed in class are library and CD ROM searc hes, organization of database systems, and "how to s urf the Internet. Assignments in this sec tion focus on topics such as "Retrieve information about injection molding of poly meric materials ," or Retrieve the latest information in the area of pulp bleaching. The search results are then reported as discussed below both orally and in the form of a written report. The added benefit of these exercises is that the students are, at the same time, also broadening their knowledge in the general area of chemical engineering. Technical Writing In this section of the course, topics s uch as techni cal writing and document layout are introduced to the students. The assignment topics (tec hnical reports) are based on information retrieved in the Obtaining Information section, and in addition, the st udents are introduced to different types of resumes. One approach that ha s proven to be s ucces s ful ( but by no means the only appropriate model) can be found in The Job Hunting Guide."C 7 l Excerpts of thi s docu ment are shown in Table 4. Guidance is provided in the resume development process through slides, hand outs, and hands-on exercises. The most important part of thi s document is the Objective sectio n. Here the writer addresses the very important issues of What skill do I bring to thi s position? and "W hat can I do for the Company?" The insight obtained in the sec tion on Critical Thinking Skills will guide the partici pants in the development of this subsection. 86 TABLE4 The Resume A Very Effective Marketing Tool The next s t ep, after having successfu ll y comp l eted the career-p l ann in g phase is the development of a resume. If developed properly it can be a highly effective marketing tool. It s two main purposes are to advert i se yo ur availability and to s upply information to the recruiter. How s h o uld a resume be prepared? Perhaps the most import ant thing to remem ber i s that the format must capture the recruiter. It s hould enable the recruiter to quickly find the key point s Clear h eadi n gs, off-w hite paper, a nd point format are desirable. R emember that yo u will have l ess than ten minutes to prove to the person th at you are an except ion a l candidate. Effective u se of l anguage, emphasis on achievements and quantified expe rience are thus important aspects of a resume. There are three basic formats being used t oday. The most widely used and accepted fo rm at, the c hron o l ogical sty l e, lists your experiences in reverse c hron lo g ic a l order. This s tyl e emphasizes yo ur most recent ac hievem ents The function a l format li sts the duties performed by category. With this sty le it i s harder for the recruiter to get an in s tant picture of the candidate. The third type which i s not widely u sed, i s a hybrid of the chronological and the functional format sty l es. What key information shou ld a resume conta in ? The following eleven categories should be included: Personal Data The only data required are your nam e, addres and phone numb e r. Your fax number and e-mai l address are optio n a l. One would not wa nt to s upply information such as religion marital stat u s, or citizenship. These are 'knock-o ut' factors that m ay or may not be used against you. You do not want to limit you r chances ri g ht from the beginning. Career Objective There is some debate on whet h er or not this sect ion s h ou ld be includ ed in a resume. U nl ess the object i ve i s written carefully, do not include it. This sectio n sho uld s h ow w h at you ca n d o for the company and NOT w h at the company can d o for you. A samp le objective for a person who h as participated in a Co-Op Profe ss ion a l Experience Program could read: To provide leadership in industrial res e ar c h and d eve lopment activities where streng th in superior analysis of data problem solvin g, innovation and excellent commu ni cation skills will: design and develop new technologies provide opportunity for te c hnology transfer train and motivat e staff, and generate r es ults consistent with organizational initiativ es Professional Profile This summarizes your professional experience in a few s h o rt sentences. The following co uld be used as a g uid e lin e: "Engineering ex perience r elating to inje c tion moldin g, process automation and th e modelin g of PET resin dr y ing pro cesses." Education List your education in reverse chrono l ogical order. Do not include your hi gh sc hool education if you hav e a college or university degree. Work Experience Describe all the relevant work experiences here. Use action verbs s uch as directed developed, implemented designed, and presented to describe yo ur accomp li shments. Do not forget to include yo ur job titles, times of employ ment, a nd the n ames of your emp l oyers Selected Ach i evements This section s h ou ld li s t a maximum of three work/educa tion-related accomp li shme nt s in more detail. Professional Development This category sho uld include a ll professional develop ment activities that yo u have und ertaken ouside of the sta nd ard engineering curricu lum. Scho l ars hip s List all your sc holar s hips Professional Affiliations Are you a member of a profe sio n organization? List it here Languages Indic ate the l anguages yo u know and yo ur l eve l of competence If you are fluent in English and can "ge t by in Spanish you s hould write "Fluent in English and functional in Spanish ." References Available up on request. Do not include th e names of your (t hree ) references in your re s um e. Prepare the list of r eferences on a separate s he et to be used as a handout during the interview Chemical Engineering Education

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TABLES Oral Presentation Evaluation Form Co111111e11ts/Mark A significan t amount of effort by the s tudents is volun tarily directed toward the development of this document. This high degree of moti vat ion ma y be attributed to the fact that they are doing so methjng for their own benefit i.e. they can apply these skills during their st udi es as well as in their life after university. Opening Statements Did the speak s tate her/hi s nam e? Did the pre se nter state th e topi c? Did th e presenter s tat e the purpose ? Did th e pr ese nter outline the pr ese nt ation? Organization I s there a logical flo w o r a ramblin g monologue ? Does th e pr ese ntation tar ge t th e audience ? I s the presentation informing or merely trying to impr ess? Presentation I s presenter enthusiastic abo ut the topi c? Is th e s peakin g clear or mumbled? I s the presentation deliv e red in a professional m an n er? Was eye contact made ? Is the talk too lon g (pas t target time) ? W e re the gestures distracting? I s the s peaker s till or walking n ervo u sly? Is the dress co d e appropriate? Is the presentation natural and not re a d ? Visual Aids I s the layout of the visuals appropriate ? Do th ey contain a reasonab l e amo unt of information? Are th ey referred to rather than read from? I s the grammar correct ? Are th ey shown for l ess than one minute ? Subject Knowledge Does the pre se nter ma s ter the s ubj ect? Closing Remarks Is the objective sta tement repeated ? Is the presentation summarized? Are proper acknowledgments made ? Were the questions answered co nci se l y? TABLE6 Discu ss ion and Listening Skills Presentation Skills An emphasis on the development of presentation skills in univer s itie s has s ignific an tly increased over the past decade .l 2 81 In our course, each s tudent is given the oppor tunity to make a formal presentation to the entire class twice during the term In a short, three-mjnute presenta tion topic s such as The use of NaCl in the pulp and paper industry or "Recent development s in the area of power generation are presented to the whole clas s. Also, a ten minute presentation summarizes the re s ults obta ined in the Obtaining Information section. A detailed discus s ion on the presenter 's perf01mance i s scheduled on a one to-one basis. The Oral Presentation Evaluation Form (Table 5) serves as an aid in this process. In addition to these "formal" presentations the students participate actively in short exercises throughout the term. At the beginning of each lecture one student, selected at random by the instructor must summarize the previous class in about three minutes. Thi s exercise serves two purpo ses: everybody comes to class prepared and it gives the s tudents yet another opportunity to hone their presentation skills. In addition to the above described exercises, students enjoy frequently-he ld "one-minute" impromptu talk s Discussion and Listening Skills Interviewer_ ________________________ The way a per so n asks and answers ques tions impact s significantly on the working en vironment. Questioning is a valuable tool a nd is critical to the oral communication process. Many successful approaches have been de scribed in the literature. 19 101 The st udent s learn about and practice how to ask, as well as how to answer, two basic types of questions : open ended and closed-ended. Interviewee:------------------------Question: ___ __ ____ ___ _____________ Or que stio n number from li s t __ Needs Evaluatio 11 of lllt erviewer l111prove111e11t Good Short Co111111e11ts Eye contact __________ _______ _______ Body l anguage _______________________ Oral co mmuni ca tion---------------------Self-confidence : Think on yo ur feet. ---------------Evaluatio11 of llltervi ewee Nee ds /111prove111e11t Good S h o rt Co111 111 e11ts Eye contact _________________________ Body l a n g u age _______________________ Oral comm uni cat ion ______________________ Self-confidence: Think on your feet. ________________ Mor e deta il ed co mments from th e observer should be submitted on a separate sheet. Name ----------Dat e _____ Winter 1998 As the communication process suggests, for communkation to be congruent, one has to clearly understand the other's frame of refer ence The students gain this understanding by asking question s that will clarify and confirm the messages others are sending to them. After the students were encouraged to engage in dis cussions, they observe and diagnose the other's verbal and nonverbal messages. Through group exercises and continuous feedback (see Table 6) one observes significant improvements in 87

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the students' performance. Real Life Situations Employers emphasize that interpersonal and communications skills are as important as tech nical knowledge. Through group exercises, the s tudent s are given seve ral opportunities to prac tice different interviewing s ituations Learning how to ask question s, and learning how to answer difficult ones doe s not come quickl y Practice make s perfect. The sk ill s and knowl edge obtained in this course help the students to overcome interview anxiety. We should not onl y teach our students the necessary tools portive. Thi s wi ll help e n s ure that the established goals are s ucc ess ful and are harmoniou s with those of the re s t of the clas s By the end of the course, the s tudent s have not only s ignificantly enhanced their communication ski ll s, which of course is our main objective, but th ey s hould h ave also gai ned an e nhanced se lf awareness that will help them along their chosen career path. to enable them to survive in a work environment but we should CONCLUSIONS also assist them in their A course s uch as Communications and Infor m a tion System s" can be taught through the appli cation of real life situations. Although there are currently many discus s ions being h e ld about the uni ve r s it y's role in today 's society, the author strongly b e li eves that if one strikes the proper DISCUSSION The purpose of thi s course i s to help s tudents hone their communication ski ll s. In addition the s tudent s will learn more about them se lve s and their goals. The se technique s, te s ted and transition from the university to industry. refined over man y years, work we ll in both univer s ity and non-uni vers ity environments When the concept was first being introduced there were comments from our s tudent s s uch as : [> [> This instructor i s cra z y H e is trying to teach us co mmuni cat ion s kill s and at th e sa m e time he is asking us to l earn more about ourse l ves!" / am ju st a seco nd year student. I can t u se this co n cept to go after technical summer jobs! After a few students tried the approach, the following comment s were made : [> / got a job using the communication ski ll s and job hunting techniques that I l ea rn ed in your class. [> Thank you for you r efforts. My co mmuni cat i on skills improved sig nifi ca ntl y Initi a ll y, the s tudent s ha ve to learn how to overcome their fears Active support by th e instructor is the key in this proce ss. Support begin s with the instructor 's in-depth under s tandin g of the co ur se m a terial and it s adaptation to the s pecific learning environment. Thi s course, unlike ordinary lecture courses, re quire s a s ignifi can t amount of s tudent/in str uctor interaction outside the scheduled cla ss time. During the course of the term the instructor s hould have severa l private review meetings with each st udent. The focus of these meetin g s hould be on work ing to get her to achieve th e goals that were set out in the course outline. By answering que s tion s, resolving problem s, and emphasizing good communication skills, the se meeting s can help foster a n understanding and a s trong commitment of the learner to her/his chosen profe ssio n The instructor 's responses during the meeting s s hould b e po s itive and s upBB b alance betwe en the economically driven goals (i.e., the education of marketabl e s tudent s) and the more traditional goals of the uni ve r s ity ( i. e., let 's educate great thinker s), thi s approach will serve the st udent s well in the future Let us not lo se sight of the result s we see k to achieve as we focus of the proce ss of providing relevant chemical engineering education for the 21st century." l 1 0 1 ACKNOWLEDGEMENTS Th e author would lik e to thank Brian Lo wry for hi s va lu able input on th e "jo b hunting topi c while co-teac hin g the ChE 1014 course. Special thank s are due to Frank Collins Robin Chaplin Don Wood s and all the course/seminar par ticip a nt s for their assistance in refining the concepts. REFERENCES 1. Bendrich G. and B J Lowry, "Communications and Infor mation Systems Course Material," University of New Brunswick ( 1996 ) 2 Nirdosh I. Making Successful Oral P rese ntation s-A Guide, Chem. Eng. Ed. 31(1 ) 52 ( 1997 ) 3. Lordeon S.L C. H Miles, an d M. Kean e Some Assembly R equired-A Complet e Guide to Technical Communications, McGraw-Hill Ry e rson Limited, Toronto Canada ( 1997 ) 4. Covey S.R. Th e 7 Hab its of Hi ghly Effective People Simon & Schuster New York NY (1989 ) 5 Butl e r G., an d T Hop e Managing Your Mind, Oxford Uni versity P ress, N ew York NY ( 1996 ) 6. DeBono E. Six Thinking Ha ts Penguin, New York NY ( 1985 ) 7 B e ndrich G. "T h e Job Hun ting Guide," Personal Notes ( 1994 ) and http :// www unb.ca/che ( 1997 ) 8 Newell, J A. D .K. Ludlow an d S.P.K. Sternberg, D eve lop ment of Oral and Written Communi cation Skills," Chem. Eng. Ed ., 31 ( 2 ), 116 ( 1997 ) 9 Kauffman, K.J., How to Make Questioning Work for You," Chem. En g. Ed., 3 1 (2 ) 134, ( 1997 ) 10 McKeachie W.J., T eaching T ips, D.C. H eat h a nd Company L exington KY ( 199 4 ) 11 Buonopan e, R.A. Engineering Education for the 21st Cen tury," Ch e m. Eng. Ed. 31 ( 2 ) 166 ( 1997 ) 0 Chemical Engine e ring Education

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AUTHOR GUIDELINES This guide is offered to a id authors in preparing manuscripts for Chemical Engineering Education (CEE) a quarterly journal publis h ed by the Chemical Engineering Division of the American Society for Engineering Education (ASEE) CEE publishes papers in the broad field of chemical engineering education. Papers generally describe a co ur se a laboratory a ChE department a ChE educator a ChE curriculum research program machine computation specia l instructional programs, or give views and opinions on various topics of interest to the profession. Specific suggestions on preparing papers TITLE Use specific and informative titles They s hould be as brief as possible, co n sistent with the need for defining the subject a r ea covered by the paper. AUTHO R SHIP Be consistent in authorship designation. Use first name, second initial, and surname. Give complete mailing address of place where work was conducted. If current address is different, include it in a footnote on title page ABSTRACT: KEY WORDS Include an abstract of l ess than seventy-five words and a list (5 or less) of keywords TEXT We request that manuscripts not exceed twelve double-spaced typewritten pages in length. Longer manuscripts may be returned to the author(s) for revision/shortening before being reviewed. Assume yo ur reader is not a novice in the field. In c lud e only as much history as is needed to provide background for the particular material covered in your paper. Sectionalize the article and insert brief a ppropri ate headings. TABLES Avoid tables and graphs which involve duplication or superfluous data. If you can use a graph, do not include a table If the reader needs the table, omit the graph. Substitute a few typical results for lengthy tables when practical. A void computer printouts NOMENCLATURE Follow nomenclature style of Chemical Abstracts; avoid trivial names. If trade n ames are used, define at point of first use Trade names should carry an initial capital only, with no accompanying footnote. Use co n sistent units of measurement and give dimensions for all terms. Write all equations and formulas clearly, and number important eq u ations consecutively. ACKNOWLEDGMENT Include in acknow l edgment only such credits as are essential. LITERATURE CITED References shou ld be numbered and listed on a separate sheet in the order occurring in the text. COPY REQUIREMENTS Send two l egible copies of the typed (doub l e-spaced) manuscript on standard letter-size paper. Submit origina l drawings (or clear prints) of graphs and diagrams on separate sheets of paper, and include c l ear g l ossy prints of any photographs that will be used. Choose grap h papers with blue cross-sectio n a l line s; ot h er co lor s interfere with good reproduction. Label ordinates and abscissas of graphs a l ong the axes and o ut side the graph proper. Figure captions and l egends will be set in type a nd need not be lettered on the drawings. Number a ll illustrations consecutive l y. Supply a ll captions and l egends typed on a separate page. State in cover letter if drawings or photographs are to be returned. Authors should also include brief biographical sketches and recent photographs with the manuscript. Send your manuscript to Chemical Engineering Education c/o Chemical Engineering Department University of Florida Gainesville FL 32611-6005

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A KNOWLEDGEMENT DEPARTMENTAL SPONSORS The following 161 departments contribute to the support of GEE with bulk subscriptions. If your department is not a contributor, write to CHEMICAL ENGINEERING EDUCATION c/o Chemical Engineering Department University of Florida Gainesville, FL 32611-6005 for information on bulk subscriptions University of Akron University of Alabama University of Alabama, Huntsville University of Alberta University of Arizona Arizona State Universitv University of Arkansas Auburn University Ben Gurion University of the Negev Brigham Young University University of British Columbia Brown University Bucknell University University of Calgary University of California, Berkeley University of California, Davis iversity of California, Irvine Univer y of C~lifornia, Los Angeles Universitv of California, Santa Barabara California Institute of Technology California State University Carnegie-Mellon University Case Western Reserve University University of Cincinnati Clarkson University Clemson University Universitv of Colorado Colorado School of Mines Colorado State Universitv Columbia University University of Connectict;t Cork Regional Technical College Cornell University Dalhousie University Dartmouth College University of Dayton University of Delaware Drexel University Universitv of Florida Florida Institute of Technology Florida State/Florida A&M University Georgia Institute of Technology Hampton University University of Houston Howa~d University University of Idaho University of Illinoi~. Chicago University of Illinois, Urbana Illinois Institute of Technology University of Iowa Iowa State University Johns Hopkins University University of Kansas Kansas State University University of Kentucky Lafayette College Lakehead Universit Lamar Uni rsity Laval Universty Lehigh Universiiy Loughborough University Louisiana State University Louisiana Technical Univer~itv University of Louisville Universitv of Maine Manhatt~n College Marshall University Graduate College University of Maryland University of Maryiand, Baitimore County Universit. of Massachusetts University of Massachusetts, Lowell Massachusetts Institute of Technology McMaster University McNeese State University University of Michigan Michigan State University Michigan Technical Universitv Universitv of Minnesota University of Minnesota, Duluth University of Mississippi Mississippi State University University of Missouri, Columbia University of Missouri, Rolla Mon.ash University Montana State Universitv University of Nebraska University of Nevada at Reno University of New Hampshire University of New Haven New Jersey Institute of Technology University of New Mexico New Mexico State University North Carolina A & T Universl North Carolina State Universitv University of North Dakota Northeastern University Northwestern Universiiv University of Notre Da~e Ohio State Universitv Ohio University Universitv of Oklahoma Oklahoma State University Oregon State University Universitv of Ottawa Universitv of Pennsylvania Pennsvlva~ia State U~iversitv University of Pittsburgh Polytechnic Institute of New York Princeton University Purdue University Queen's University Rensselaer Polyte~hnic Institute University of Rhode Island Rice Universitv University of Roches! Rose-Hul~an Institute of Technology Ro an College Rutgers, The State University Ryerson Polytechnic University San Jose State University University of Saskatchewan University of Sherbrooke University of South Alabama Universitv of South Carolina South Dakota School of Mines University of South Florida University of Southern California University of Southwestern Louisiana State University of New York, Buffalo Stevens Institute of Technology University of Sydney Svracuse University University of Tenn~ssee Tennesse~ Technological University Universitv of Texas Texas A & M University, College Station Texas Tech University University of Toledo Tri-Stale University Tufts University University of Tulsa Tuskegee University University of Utah Vanderbilt University Villanova University. University of Virginia Virginia Polytechnic Institute University of Wales, Swansea University of Washington Washington State University Washington University University of Waterloo Wayne State University West Virginia Institute of Technology West Virginia University Widener University University of Wisconsin Worcester Polvtechnic Institute Universitv of \Vvoming Yale Uni{ersity Youngstown State University