Citation
Chemical engineering education

Material Information

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.

Subjects

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

Notes

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

UFDC Membership

Aggregations:
Chemical Engineering Documents

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CHEMICAL ENGINEERING EDUCATION
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EDITORIAL AND BUSINESS ADDRESS

Department of Chemical Engineering
University of Florida
Gainesville, Florida 32611

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Chemical Engineering Education
VOLUME XIX NUMBER 3 SUMMER 1985

The Educator
110 Dendy Sloan of the Colorado School of Mines,
Brodie Farquhar
Department
114 The University of Utah, Norman W. Ryan
Views and Opinions
120 Are We Participants or Victims?, James Wei
162 Adjunct Position: One Way to Keep Up With
Technology and Education, Richard D. Noble
Classroom
121 The Teaching of Process Design, T. K. Sherwood
132 Improvements in the Teaching of Staged Operations,
Maryam Golnaraghi, Paulette Clancy, Keith E.
Gubbins
148 Estimation of Fluid Properties and Phase Equilibria,
M. Herskowitz
156 Fundamentals of Chemical Processes,
William R. Moser
Laboratory
124 A Junior Year ChE Laboratory, W. R. Paterson
136 Recycle With Heating: A Laboratory Experiment,
A. Foord, G. Mason
150 An Innovative ChE Process Laboratory, Skip
Rochefort, Stanley Middleman, Pao C. Chau
Curriculum
128 Basic Information Science Training for Chemical
Engineers, O. M. Kut, R. Queralt, L. M. Rose
Feature
144 Impact of Packaged Software for Process Control
on Chemical Engineering Education and
Research, Brian Buxton
Class and Home Problems
140 One Month Problem: An Exercise in Modelling,
V. Ravichandran
113 Positions Available
118 Book Review
119 Division Activities
135 Letter to the Editor

CHEMICAL ENGINEERING EDUCATION is published quarterly by Chemical
Engineering Division, American Society for Engineering Education. The publication
is edited at the Chemical Engineering Department, University of Florida. Second-class
postage is paid at Gainesville, Florida, and at DeLeon Springs, Florida. Correspondence
regarding editorial matter, circulation and changes of address should be addressed
to the Editor at Gainesville, Florida 32611. Advertising rates and information are
available from the advertising representatives. Plates and other advertising material
may be sent directly to the printer: E. O. Painter Printing Co., P. O. Box 877,
DeLeon Springs, Florida 32028. Subscription rate U.S., Canada, and Mexico is $20 per
year, $15 per year mailed to members of AIChE and of the ChE Division of ASEE.
Bulk subscription rates to ChE faculty on request. Write for prices on individual
back copies. Copyright 1985 Chemical Engineering Division of 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 of the ASEE
which body assumes no responsibility for them. Defective copies replaced if notified
within 120 days.
The International Organization for Standardization has assigned the code US ISSN
0009-2479 for the identification of this periodical.


SUMMER 1985









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Colorado School of Mines


BRODIE FARQUHAR
Colorado School of Mines
Golden, CO 80401

T DENDY SLOAN IS AN academic man for all
Seasonss" said Art Kidnay, department
head of Chemical Engineering and Petroleum Re-
fining at the Colorado School of Mines. "He
is one of those rare individuals who does every-
thing well."
Professor Sloan is a renaissance figure, on a
campus and in a discipline dominated by special-
ists. "Dendy is the most balanced, well-rounded
faculty member I know," said Kidnay. "That is
what sets him apart. Other faculty on campus
and around the nation are equally competent in
areas like teaching, committee assignments, re-
search, engineering education research, and work
in the professional societies-but I don't know
anyone quite as good in all areas."
The shelves in Sloan's office contain the usual
and the unexpected. Chemical engineering texts
and journals dominate, as do two large models of
hydrate molecules. What is different is the strong
presence of books of philosophy and literature.
Books like Zen and the Art of Motorcycle Main-
tenance by Robert Persig, and Whitehead's The
Aims of Education nestle with books by William
Shakespeare, Herman Hesse and Robert Frost.
The hydrate molecular models represent the
specialization Sloan has sought, while the philoso-

"We're still teaching like Saint
Thomas Aquinas in the Thirteenth Century,
lecturing in front of a group of students.
How do we integrate new tools like computers? They
are no panacea, yet I believe that the key is
in experiential learning, case studies,
and real-life problem solving."

Copyright ChE Division, ASEE, 1985


phy and literature books represent a curiosity
that has never been satisfied with the comfort of
settling into a familiar niche.
"Dendy teaches a variety of courses," said
Kidnay, "and by next year, he will have taught
every undergraduate course in our department.
He's done this voluntarily. Very few faculty can or
would do something like that-most prefer to
specialize near their own research interests,
which makes it easier to teach. I know that some
schools have a policy to force faculty to rotate
through the curriculum in the interest of balance
and keeping up with all areas of your discipline.
We don't have that policy, simply because most
of us don't have the time. Dendy is the only one
I know who could pull it off."
Born in Seneca, South Carolina, in 1944,
Dendy developed an early interest in math,
science, chemistry, and physics in high school.
He earned his BS in chemical engineering from
Clemson University in 1965 and worked five years
for duPont, working in Tennessee, Delaware,
West Virginia, and South Carolina. "In the course
of those four jobs with duPont," said Sloan, "I
discovered that I enjoyed opportunities to be
entirely self-motivated and directed. Teaching
seemed like a good way to do that."


CHEMICAL ENGINEERING EDUCATION








In light of his later professional accomplish-
ments, getting into graduate school should not
have been a problem. It was. "Dendy did not
have outstanding grades as an undergraduate,"
said his Clemson uppergraduate advisor, Dr. Jo-
seph Mullins. "As I recall, he was active in a band
and still plays a pretty hot banjo. The depart-
ment chairman suggested he take some math
courses and reapply." Several night courses and
A's later, Sloan entered the graduate program
at Clemson.
"Dendy was the most organized student I've
ever had," said Mullins. "He came early and
stayed late and ran during the lunch hour. Pretty
soon he had most of the grad students chugging
away, running with him." (Sloan has run 12
marathons and typically has put in 40 miles per
week over the past 20 years.)
It was at Clemson University that Sloan's role
models for teaching made their impact on his
career. "Clemson had an unusually strong focus
on education," said Sloan. "People like Joe
Mullins, Dick Harshman, and department chair-
man Charles Littlejohn had a real impact. As I
got into graduate education, I realized that this
was what I wanted to do with my life."
Sloan earned his MS from Clemson in 1972,
with the thesis title of "The Combined Effects of
Natural and Forced Convection in a Dual Mem-
brane, Horizontal Parallel Plate Ultrafilter"; and
his PhD in 1974, with the thesis title of "Non-
ideality of Binary Adsorbed Mixtures of Benzene
and Freon-11 on Highly Graphitized Carbon at
298.15 K and Pressures below 10 Torr."
"I advised Dendy to get his PhD elsewhere,"
said Mullins, "but he insisted on getting it here.
I did persuade him on the wisdom of doing post-
doctoral work elsewhere." Elsewhere turned out
to be Rice University, where Sloan encountered
Dr. Riki Kobayashi and worked as a research
fellow on determining the water content of
natural gas in equilibrium with hydrates.
"It was a very high pressure time and environ-
ment," said Kobayashi. "Dendy was responsible
for measuring and setting the water content specs
for a high pressure natural gas pipeline, from
Alaska to the lower 48. Dendy, along with Jerry
Holder (currently at the University of Pitts-
burgh), is currently recognized as one of the
primary researchers (in addition to Dr. Koba-
yashi) in the area of hydrates. The energy crisis
really had us going-so much so that I bought a
rollaway bed for Dendy. He never complained."


Methane hydrates are a molecular bond of water
and natural gas, under pressure. Under certain
conditions, hydrates can build up in a pipeline
and plug it.
From that initial focus on hydrates as a prob-
lem, Sloan eventually branched out to explore
methane hydrates as an energy solution. Rich
fields of methane hydrates exist in deep oceans,
as well as in permafrost regions of Canada,
Alaska and Siberia. It is estimated that under
United States land and territorial waters alone,


"Once a student learns the process
of learning and solving real-world, open-ended
problems, he or she will never have to worry about
the half-life of his or her knowledge-
they'll be life-long learners."

there are enough hydrate deposits to provide
natural gas supplies for at least 150 years, or 15
times the known supply of conventional natural
gas. This unconventional form of natural gas is
currently thought of as a future resource, and
some of Sloan's research studies is currently spon-
sored by the U.S. Department of Energy.
Sloan came to the Colorado School of Mines
in 1976. Here he taught most of the undergradu-
ate courses, specializing in thermodynamics, phase
equilibria, and stagewise process design at the
graduate level. His research proceeded with
natural gas hydrates and included adsorption,
phase equilibria, and thermal conductivity. He
came for the professional opportunities, the high
caliber of students, and the high degree of lati-
tude Mines offers its faculty, who enjoy both
teaching and research. He has stayed for these
and other reasons.
"This is small town America," said Sloan, re-
ferring to his nine years in Golden. "You have
the friendliness of a small community-Cub
Scouts, a good church-and access to a big city.
This is a good family place." That's important
to Sloan and his wife, Marjorie, and his two sons
-Trey, 13 and Mark, 10. Sloan has been active
in the Scouting movement for six years and has
served as an elder in the Presbyterian Church.
Marjorie is a second year law student at the Uni-
versity of Colorado. "I've had offers for other
positions, yet I haven't been able to convince my-
self that I'd be happier elsewhere," said Sloan.
Has he noticed any similarities between Cub
Scouts and college students? "Eight- to ten-year-
olds are bundles of unchanneled energy. You've


SUMMER 1985








got to plan things that will hold their interest;
otherwise they climb the walls. Students 18-22
years old are generally very bright and very
channeled," said Sloan. "Graduate student per-
sonalities typically mirror those of the professor,
but undergraduates can be a substantially differ-
ent challenge. Working with undergraduates is
one of the best motivators for coming into this
profession, and when a school has as good


Sloan and his Cub Scout
big race.


troop getting ready for the


students as CSM does, it makes teaching doubly
pleasurable."
Evidently, his ability to hold an eight-year-
old's attention has rubbed off on his college teach-
ing style. Students consistently rank him as one
of the best teachers on campus, year after year.
His peers have also recognized his teaching skills
by honoring him with the AMOCO Teaching Ex-
cellence Award at CSM, and with the Western
Electric Award from ASEE.
Currently, Sloan works with eleven graduate
students in research focused on natural gas
hydrates, vapor liquid equilibrium, and thermal
conductivity. In 1982, Dr. Sloan acquired the first
Western sample of methane hydrates when the
Glomar Challenger brought up samples from the
ocean floor off the coast of Guatemala. Shipped
in chilled and pressurized containers to Sloan, the
"dirty snowballs" have been divided up among
laboratories at CSM and other schools. Sloan and
his graduate students are trying to determine
optimum in situ methods of releasing condensed
methane molecules from the water molecules
which surround them.
One of the frustrations of running a success-
ful research operation is lack of time for personal,


hands-on research. "We come in as researchers
and become research managers. There is no time
for lab work. I find time for some theoretical and
computer work, but I really miss working in the
lab," said Sloan.
In spite of these limitations, Sloan does find
time for a number of other activities. These in-
clude professional service in the ASEE and other
organizations, service on a variety of CSM com-
mittees, work with the innovative EPICS pro-
gram at Mines, plus pondering philosophies of
engineering education. He even finds time to study
the personalities of faculty and students, correlat-
ing results with their career tracks.
Within the ASEE itself, Sloan is currently
Chairman of the Educational Research and
Methods Division and is Chairman-Elect for the
Chemical Engineering Division. Within CSM,
Sloan has served as chairman of the Honors Hu-
manities Tutorial Committee, and served on the
Presidential Search Committee.
"EPICS" stands for Engineering Practices
Introductory Course Sequence. Because the best
method for mastery of any skill is regular
practice, EPICS has been designed by Sloan and
other CSM faculty as a unique lab-type course,
providing "real-world" environments to develop
and practice engineering skills. "The emphasis is
on the process of learning, not the content of engi-
neering facts and figures. All the facts, figures
and cookbook procedures we pound into students'
heads have a half-life, a limited time-span of
value, due to the explosion of information and re-
search. Once a student learns the process of learn-
ing and solving real-world, open-ended problems,
he or she will never have to worry about the half-
life of his or her knowledge-they'll be life-long
learners," said Sloan.
"We're still teaching like Saint Thomas
Aquinas in the Thirteenth Century, lecturing in
front of a group of students. How do we inte-
grate new tools like computers? They are no
panacea, yet I believe that the key is in ex-
periential learning, case studies, and real-life
problem solving. Mines and Harvey Mudd are two
of the best places I know that are working toward
this new approach of engineering education," said
Sloan.
The shift from content to process will not
come easily, warned Sloan. "High school teachers
put a great deal of emphasis on content (students
regurgitating books and lectures), as do colleges,
yet we expect colleges to produce leaders and in-


CHEMICAL ENGINEERING EDUCATION









novators. Giving up emphasis on content is very
threatening. It forces teachers to continually
learn new materials, use new tools, and to do re-
search. It forces us to think."
It also forces educators to look closely at how
students feel about the process of learning. "I'm
convinced that if a student leaves a course or a
school feeling badly, then we've done permanent
damage to that student. He/she won't be as good
an engineer as someone who left a course or school
excited about what they learned. As a profession,
we're not doing a good job of addressing this
issue."
Sloan enjoys reading philosophy and does not
see the discrepancy between the "real world" and
the "world of ideas." For Sloan, engineering and
philosophy are both concerned with open-ended
problems. "I try to see things as part of a spec-
trum, not as different or isolated from the whole.
Take Robert Persig's Zen and the Art of Motor-
cycle Maintenance. It presents the classic struggle
between objective science and intuitive romance
and shows that rather than being estranged from
each other, they can be part of a whole," said
Sloan.
Personality types fit into this world view.
Using the Myers-Briggs Type Indicator (MBTI),
Sloan has found that different personalities have
different world views and are attracted to differ-
ent disciplines (see "Applications of Psychologi-
cal Types in Engineering Education", February
1983, Engineering Education).
Some people are attuned to the practical,
hands-on, common-sense view of events, while
others are more attuned to the complex inter-
actions, theoretical implications or new possi-
bilities of events. These two styles of information
gathering, or perception, are known as Sensing
and Intuition, respectively.
"Since faculty are predominantly intuitive,"
said Sloan, "and students are evenly split, I'm
concerned that we may be awarding grades based
on personality characteristics, rather than per-
formance." Intuitives do better on exams prepared
by intuitive type faculty, while sensing types do
less well-usually because they re-read every test
problem in the interest of accurate compre-
hension, and run out of time.
For Sloan, balance or integration is a key con-
cept. Just as a mature personality should be able
to integrate intuitive and sensing methods of
learning, a mature profession (engineering edu-
cation) should be able to integrate content and


POSITIONS AVAILABLE
MICHIGAN STATE UNIVERSITY
Chemical Engineering .. Tenure system faculty positions.
Doctorate in Chemical Engineering or closely related field.
A strong commitment to teaching and the ability to de-
velop a quality research program is expected. Preference
will be given to candidates with research interests in the
areas of Biochemical Engineering, Surface Science, Solid
State Phenomena, or Polymeric Materials. However, ap-
plicants with outstanding credentials and research interests
in other fields related to Chemical Engineering are en-
couraged to apply. Teaching and/or industrial experience
desirable but not essential. Michigan State University is
an affirmative action-equal opportunity employer and wel-
comes applications from women and minority groups. Send
applications and names of references to Chairperson,
Faculty Search Committee, Department of Chemical Engi-
neering, Michigan State University, East Lansing, Michi-
gan 48824-1226.

CHEMICAL ENGINEERING/MICHIGAN BIOTECHNI-
CAL INSTITUTE Assistant/Associate/ Full Professor
(full year, full time, tenure system). Biochemical engineer-
ing positions and Distinguished Research Professorship.
The Chemical Engineering Department and the Michigan
Biotechnology Institute have joint tenure system positions
open. Rank, salary and incentives commensurate with
qualifications. Applicants should have demonstrated ability
in one or more of the following areas. Bioreactor Design
and Scale-up; Product Separation and Recovery from Cell
Culture Broths; Sensors, Controls and Computer Inter-
facing of Biological Processes; and Renewable Resource
Technology. Strong commitment to applied research plus
teaching limited to graduate training in biotechnology ex-
pected. Applicants with outstanding credentials and an
active research program are encouraged to apply. The
positions offer the excitement of sharing in both the
understanding and rewards of developing new technology.
Qualified women and minorities are encouraged to apply.
Apply in writing to: Donald K. Anderson, Chairperson,
Biotechnology Search and Selection Committee, Michigan
State University, 173 Engineering Building, East Lansing,
MI 48824-1226. Applications are requested by September
1, 1985, but will be accepted as long as necessary to fill
the positions.

PROJECT ENGINEERS, Specialty Chemical Manufactur-
ing Company in Southwest Pennsylvania seeks candidates
to direct all process development activities for Emulsion
Polymer project. Requirements: Resume, PhD Chemical
Engineering plus 2 years experience as Project Engineer
or Chemical Research Engineer, PhD and employment ex-
perience must be in polymer rheology and engineering.
$47,088/year. Full time. Send resume to Charles A. Wilson,
Office of Employment Security, 300 Liberty Avenue, Room
1302, Pittsburgh, PA 15222. Job Order #3990818 DOT
#019.167-014.

process methods of teaching. To all who know him,
Dendy Sloan exemplifies a sense of balance and
wholeness, as an individual and as a professional
educator. O


SUMMER 1985































The central part of the University of Utah campus viewed from the northwest.
The Merrill Engineering building, glass and aluminum, is below and left of center.


IN department


CHE AT THE


UNIVERSITY OF UTAH


NORMAN W. RYAN
University of Utah
Salt Lake City, UT 84112

T HE UNIVERSITY OF UTAH, located in Salt Lake
City, occupies 1,500 acres and is bounded on
the east by the Wasatch Mountains. Founded in
1850, it is the oldest and, with a student popula-
tion of about 25,000, the largest institution in
Utah's system of higher education. Its essential
functions are served by a faculty of about 3,500,
with roughly half being regular teaching faculty
and half being adjunct, research, clinical, and
visiting faculty. The governance of the university
includes a Board of Regents and an Institutional
Council (both appointed by the governor) to
whom the university president reports.
The university is a complete university in the


sense that it contains a good library and a set of
professional colleges (including a renowned medi-
cal school) with supporting general education and
scholarly departments, housed mostly in the
colleges of science, humanities, and fine arts. This
proximity allows interesting collaboration among
the diverse professionals and scholars. The Col-
lege of Engineering is one of the eleven academic
colleges and consists of seven departments, one
being the Department of Chemical Engineering.
All seven departments of the college are pres-
ently housed in the Merrill Engineering Building
except for what has spilled over as the college has
outgrown its building space. Research has ex-
panded to fill the newly completed Energy and
Minerals Research Laboratory Building, and a
new classroom building (to be shared with an-
Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION








other college) will be available in about a year.
The spillover will be reabsorbed, and current
needs met.
There are rumors about hazards said to exist
in associating with the University of Utah; name-
ly, the seductiveness of the easily accessible out-
door life in mountains, canyonlands, and deserts.
Other enticements to postpone one's urgent duties
are afforded by the performances of a symphony
orchestra, a ballet company, an opera company, a
modern dance company, and several small theatre
groups. All are resident in Salt Lake City, and
most trace their genesis to the university campus.
The locals tend to euphemize the risk of these
"hazards" by praising the character-building
effects of resisting temptation-but we tolerate
(as we practice) yielding with moderation.


HISTORY

For the present purpose, history is either
ancient (1905-1947) or modern (1947-present).
In 1905, a program in chemical engineering was
first listed among the offerings of the State School
of Mines. The first B.S. in chemical engineering
was awarded in 1907. By the middle 30's the
Chemistry Department was administering the
program, but the curriculum was still listed by
the School of Mines and Engineering.
In 1943 George W. Minard, the first chemical
engineer to be recruited, joined the chemistry
faculty to supervise the chemical engineering
program. Because Selective Service shanghaied
his clientele, he took leave to serve in a local
war industry, returning full time to graduate the
class of 1947, and then resigning.
Modern history begins in 1947 with the fission
of the College of Engineering and Mines into the
College of Engineering and the College of Mines
and Mineral Industries. E. B. Christiansen was
retained as head of the new department of chemi-
cal engineering and was given the choice of
affiliating with either of the two colleges. He chose
engineering and, despite the fact that some of the
top administrators withheld their blessings, hind-
sight has confirmed the wisdom of the choice.
Professor Christiansen, with some initial out-
side help in teaching, first concentrated on recruit-
ing faculty and building a projects laboratory.
Parts of the apparatus were assembled from war
surplus equipment and parts were designed and,
to a large extent, built by undergraduate chemical
engineering students. After two years the labora-


tory was creditable, two new faculty members
had joined the faculty, and 37 new BS degrees
and the first MS degree had been awarded. The
department was ready to apply for accreditation,
applied, and was accredited in 1952.
During "Modern" times, the regular faculty
has grown on the average of one every three years.
Of the 15 members signed aboard, only two have
left, one by resignation and the other by involun-
tary transcendental reassignment. Probably, un-
less the academic charter of the department is
altered, the faculty will not be increased much
more; future recruits will be replacing those who
depart.


There are rumors about
hazards said to exist in associating with the
University of Utah; namely, the seductiveness of the
easily accessible outdoor life in mountains,
canyonlands, and deserts.


The department has attained maturity. Its
corporate goals, internally generated, are being
acted on competently; its facilities, and now its
faculty, are in a steady state of evolution; and its
composite personality, which is both varied and
dynamic, is progressive.

FACULTY
There are thirteen live bodies on the active
faculty, eleven regular, one senior research pro-
fessor, and one emeritus still active in research.
Since part of the efforts of several are devoted to
nondepartmental duties, we report only about nine
full-time-equivalent faculty. The thirteen mem-
bers of the faculty (14 including a newly hired
Assistant Professor) have earned their doctor-
ates at ten respected universities. All have ex-
perience in industry and over half have taught
elsewhere at the university level.
With respect to professional recognition at the
national level, one of the faculty, a member of the
National Academy of Engineering, is a past presi-
dent of both the American Institute of Chemical
Engineers and the American Institute of Mining
and Metallurgical Engineers, two have been
awarded the AIChE Founders' Medal, three have
been directors of the AIChE, three are Fellows
of the Institute, and one was the annual Institute
Lecturer for the Institute's Diamond Jubilee year.
One has received the NSF "Young Presidential
Investigators" award.


SUMMER 1985









The spirit has manifested itself in the last seven years in
student paper competition: first place five times, second
Student Chapter Award of Excellence has come to Utah


Two kinds of prized recognition within the
university are the awards for outstanding teach-
ing, five to ChE faculty members, and outstanding
research, three to ChE faculty members.
All but the newest recruits have served in the
less prestigious but important offices and com-
mittees, national or regional, of the Institute,
other professional societies, and governmental
agencies. As is appropriate in a university where
the principle of faculty governance of academic
matters is nominally respected (though some-
times needing defense), all faculty serve, or have
served, on policy, executive, and administrators'
advisory committees.
The present faculty members are: Richard C.
Aiken (Associate Professor), PhD, 1973, Prince-
ton University; Alva D. Baer (Professor), PhD,
1959, University of Utah; Richard H. Boyd (Pro-
fessor), PhD, 1955, MIT; E. B. Christiansen (Pro-
fessor), PhD, 1945, University of Michigan;
Donald A. Dahlstrom (Research Professor), PhD,
1949, Northwestern University; Noel de Nevers
(Professor), PhD, 1959, University of Michigan;
George R. Hill III (Eimco Professor), PhD,
1946, Cornell; Timothy Oolman (Assistant Pro-
fessor, beginning Autumn, 1985), PhD, 1985
University of California, (Berkeley); David W.
Pershing (Professor), PhD, 1976, University of
Arizona; Norman W. Ryan (Professor Emeri-
tus), ScD, 1949, MIT; Dale L. Salt (Professor),
PhD, 1959, University of Delaware; J. D. Seader
(Professor), PhD, 1952, University of Wisconsin;
Edward M. Trujillo (Associate Professor), PhD,
1975, University of Utah; and A. Lamont Tyler
(Professor and Chairman), PhD, 1965, Uni-
versity of Utah.

STUDENTS
Aside from striving together for an education
focused on chemical engineering, our undergradu-
ate students rely little on the campus to cultivate
their social life. Most live off-campus, many have
part-time employment in the city, and a signifi-
cant fraction are married. Yet through their
shared experiences in classes and in the under-
graduate seminar, managed by the student AIChE
chapter officers, they develop an impressive esprit


the regional AIChE
place five times, third place four times. The
in seven of the last eight years.


de corps.
The spirit has manifested itself in the last
seven years in the regional AIChE student paper
competition: first place five times, second place
five times, third place four times. The national
Student Chapter Award of Excellence has come
to Utah in seven of the last eight years. The
chapter's advisor, A. L. Tyler, received one of the
National Outstanding Student Chapter Counselor
Awards in 1978 and again in 1983.
Other interesting sightings of the spirit are
made during the annual undergraduate student
vs faculty (plus drafted graduate students)
basketball game, the junior vs senior softball
game, the annual student vs faculty doubles tennis
match (in which the faculty remains undefeated),
and the spring luncheon at which the seniors are
guests of the faculty. On this last occasion the
faculty experiences (and sometimes provokes),
the students' traditional irreverence, which pass-
es from calmly suppressed to delicately expressed.
With respect to statistical demography, we
regularly graduate 35 to 40 students with the bac-
calaureate each year. The numbers of advanced
degrees awarded during the last ten years were
81 Master of Engineering, 27 Master of Science,
and 30 Doctor of Philosophy. Our present facili-
ties and faculty enable us to handle a greater flow
of graduate students.

UNDERGRADUATE PROGRAM
That the curricula of all the chemical engi-
neering programs in the country are very similar
follows from the wide consensus among faculties
on the essential ingredients of the overall pro-
gram. Outside that core of consensus we find
differences in emphasis, depth, or diversity.
In Utah's chemical engineering, the most
notable instance of emphasis is seen in the three-
quarter senior projects laboratory. Two or three
students, as a team captained alternately by the
members, are assigned eight laboratory projects
during the senior year. An assignment is typical-
ly a design problem which requires that the team
operate laboratory equipment to generate the de-
sign data needed. With assignment in hand, the
team identifies appropriate equipment (or some-


CHEMICAL ENGINEERING EDUCATION


III


I I I I








times must assemble it), learns how to use it,
and determines what data to take. Next they
schedule a group oral examination by a faculty
supervisor, and when they persuade him that they
understand the project, they proceed to the final
frustrations: producing the data, using the data,
and writing the report.
In the course of the year's projects, the
student writes three detailed formal reports, and
his other five reports are technical notes or letter
reports. Every report is first read by a non-engi-
neer who grades it for the mechanics of com-
position and sometimes rejects it with sugges-
tions for improvement. When it finally passes
the preliminary reading, it goes to the faculty
supervisor who will judge its form and engineer-
ing content. A late report is downgraded sig-
nificantly. On the other hand, a report reflecting
unusual ingenuity in experiment or design is
awarded a grade bonus.
Another emphasis, perhaps its distinctiveness
already swept away by time's frantic broom, has
been our use of computers in homework and
laboratory instruction. In the laboratory, many
experiments are monitored or controlled by
microcomputers or minicomputers. In most de-
partmental courses, computer time is made avail-
able for the students on the computer center's
mainframe computer, and techniques requiring
its use have become an integral part of the course-
work. Of particular note has been leadership,
through J. D. Seader, in instruction in the use of
large process simulation programs such as
ASPEN, FLOWTRAN, and CHEMSHARE.
During the final quarter, each student is required
to complete a technical and economic design op-
timization using one of these tools.
We do not treat the diffusional processes col-
lectively as transport phenomena or under other
non-descriptive titles. Rather we share with me-
chanical and civil engineering departments the
teaching of common courses in engineering
thermodynamics, fluid mechanics, and heat trans-
fer. The students' class scheduling problems are
greatly reduced. The required mass transfer
courses are taught only in chemical engineering.
Many students desire some specialization, and
we try to guide them in choosing the appropriate
elective courses. To that end, we have established
several informal options such as living systems,
digital control, and management; or we may ap-
prove alternative schemes of electives proposed
by them.


GRADUATE PROGRAM
Four advanced degrees are offered in the de-
partment: Master of Engineering (ME), Master
of Science (MS), Master of Philosophy (MPhil),
and Doctor of Philosophy (PhD). Each aspirant
is limited with respect to which of the degrees he
may apply for, depending on his performance in
a combination diagnostic and screening examina-
tion. This preliminary judgment may be appealed
later on the basis of the student's subsequent per-
formance.
The ME degree, design-oriented, is popular
with BS-ChE holders and graduates from related


View in the undergraduate Projects Laboratory.

fields who want advanced treatment of chemical
engineering, with opportunity for further study
in related fields or mathematics. Much the same
can be said for the MS degree, except that it is
research-oriented and it is sometimes a first step
to the PhD.
The PhD is a research degree for which
candidacy is deferred until the aspirant passes a
qualifying examination. That examination takes
the form of preparing and defending a research
proposal in which the prospective candidate is re-
quired to demonstrate originality and independent
thought. The dissertation, with very rare ex-
ceptions, must exhibit an essential experimental
component.

RESEARCH
Research in Utah's chemical engineering de-
partment is aimed at the education of degree
candidates, with the faculty's role being maximal-
ly advisory, minimally supervisory. The benefits
of the research in faculty development are regard-


SUMMER 1985








ed as a bonus. Most (if not all) single-author
publications by the faculty have not been de-
signed to present new research findings, but
rather have been intended to be either pedagogi-
cal, critical, or entertaining.


A furnace used in research on air pollutant formation.

The line of research of greatest longevity in
the department has dealt with the rheology of
non-Newtonian fluids, both the characterization
of detailed fluid motion and its use in describing
bulk flow. Related but independent projects have
dealt with two-phase flow, with liquids and solids
distributed in gases, with solids and gases dis-
tributed in liquids, and with fluid mechanics and
heat transfer for flow in curved tubes with and
without chemical reaction. In addition, a study
of the fluctuating boundary layer in nominally
"steady-state flow" was made.
The research having the longest period of
continuous sponsorship, and consequently gener-
ating the largest number of advanced degrees, has
studied the combustion of condensed fuels. The
chief interest has been in the transients of ig-
nition, oscillating combustion, and extinguish-
ment. Much of the effort has involved the burning
of solid composite rocket fuels, and some, the
burning of the polymers and oxidants separate-
ly, with clear relevance to fires. This work quali-
fied the University of Utah to host the Thirteenth
Symposium (International) on Combustion on
our campus in 1970.
The combustion research activity just men-
tioned has diminished in intensity. Meanwhile,
another class of combustion projects has become
the most active. This research involves coupled
experimental and theoretical work on the control
of acid rain pollutants (primarily NO, NO2, SO2,
and SO,) under conditions typical of those found


in coal-fired industrial furnaces, boilers, and
kilns; the direct combustion of biomass fuels; and
the incineration of hazardous industrial wastes in
rotary kilns.
As one would expect in a university so situ-
ated, there is active research, though with a lesser
sense of urgency than expressed a few years ago,
on coals, oil shales, and tar sands. They are
characterized and variously processed to produce
liquid fuels.
A recent subject of research which has been
advanced notably in this department is computer-
aided process synthesis and design. Methods have
been developed for synthesizing multicomponent
separation systems based on considerations of
second-law analysis. Most recently, robust com-
putational procedures based on homotopy con-
tinuation have successfully been applied to inter-
linked separation systems, with the surprising
discovery of multiple solutions. O

POSTSCRIPT
If the reader has residual questions about
chemical engineering at the University of Utah,
he is invited to correspond with the chairman of
the department, Professor A. Lamont Tyler.



S9 book reviews

APPLIED COST ENGINEERING, 2nd Edition
by F. D. Clark and A. B. Lorenzoni
Marcel Dekker, Inc., 368 pages, $32.50 (1985)
Reviewed by
James H. Black
University of Alabama
This book is a revised, updated, and expanded
version of a very successful (six printings) pre-
decessor. It is of particular use in explaining how
to develop and use cost estimating tools, how to
manage and use estimating data, how to avoid
estimating pitfalls, and how to solve estimating
problems. It also covers such topics as the use of
estimates for cost control functions during the
conceptual engineering, the detailed engineering,
and the construction stages of project develop-
ment. With the techniques described in this book,
one can find out how to measure and forecast pro-
ductivity and to control, rather than just report,
costs. The book emphasizes cost estimating and
Continued, next page.


CHEMICAL ENGINEERING EDUCATION










13 3 CHEMICAL ENGINEERING

4 DIVISION ACTIVITIES

TWENTY-THIRD ANNUAL LECTURESHIP AWARD
TO DAN LUSS
The 1985 ASEE Chemical Engineering Di-
vision Lecturer was Dan Luss of the University of
Houston. The purpose of this award lecture is to
recognize and encourage outstanding achievement
in an important field of fundamental chemical
engineering theory or practice. The 3M Company
provides the financial support for this annual lec-
ture award.
Bestowed annually upon a distinguished engi-
neering educator who delivers the Annual Lecture
of the Chemical Engineering Division, the award
consists of $1,000 and an engraved certificate.
These were presented to this year's Lecturer at
the Annual Chemical Engineering Division Ban-
quet, held at the Georgia Institute of Technology.

ChE's RECEIVE HONORS
A number of chemical engineering professors
have been recognized for their outstanding
achievements. Max Peters was the recipient of the
Fred Merryfield Design Award, given annually
to an engineering educator who exhibits excel-
lence in teaching engineering design, and the
Senior Research Award was presented to Robert
Brodkey in recognition of his significant contribu-
tions to engineering research. Friedrich G. Heffe-
rich, Richard D. Noble, and Richard M. Felder all
received AT&T Foundation Awards, honoring


them as outstanding engineering teachers, while
the Dow Outstanding Young Faculty Award was
presented to Marc Donohue, James M. Peterson,
and Mark E. Davis. The grade of ASEE Fellow
Member was conferred on Ray W. Fahien in
recognition of his outstanding achievements and
important contributions.

NOMINATIONS FOR 1985 AWARD SOLICITED
The award is made on an annual basis with
nominations being received through February 1,
1986. The full details for the award preparation
are contained in the Awards Brochure published
by ASEE. Your nominations for the 1985 lecture-
ship are invited. They should be sent to Professor
Angelo J. Perna, New Jersey Institute of Tech-
nology, Newark, NJ 07102 (201-596-3616).

NEW DIVISION OFFICERS
The ChE Division officers are: Dendy Sloan,
Chairman; Deran Hanesian, Past Chairman;
Phillip C. Wankat, Chairman Elect; Bill Beckwith,
Secretary-Treasurer; and A. Lamont Tyler, Gary
Poehlein, and Carol Dedrick, Directors.

NEW AWARDS
Two new Divisional awards have been es-
tablished and will be presented at the annual meet-
ing each year. One, the William H. Corcoran
Award, will honor an author for the most outstand-
ing paper published in Chemical Engineering
Education during the preceding year. The second,
the Joseph J. Martin Award, has been created to
recognize authorship of the best paper published
in the proceedings from the prior year.


cost control, two of the more important aspects
of the field of cost engineering.
This book would find application as an ad-
vanced undergraduate-graduate level text in such
courses as Process Design and Economics, Cost
Engineering, Cost Estimating, Project Manage-
ment, Project Control, and Construction Manage-
ment. The first edition has found application this
way since its appearance seven years ago, and this
revised edition will continue that tradition.
Practicing engineers, entering cost estimating for
the first time, would find this book an indispens-
able aid.
For convenience, the book has been divided
into three parts; namely, cost estimating, cost


control, and case studies. Part III, the case studies,
is a collection of ten examples to illustrate the
principles of cost engineering. These case studies
are designed to provide understanding of the
underlying principles discussed in the first two
parts of the book.
The new features of this book include, in ad-
dition to the case studies and the latest develop-
ments and improvements in cost estimating and
cost control, several new aspects of cost engi-
neering so that the book reflects recent advance-
ments in the field. A new chapter on control of
subcontracts has been added because of the in-
creased importance of this topic today. There are
Continued on page 161.


SUMMER 1985


III








EDITOR'S NOTE: A controversy is brewing on the design content of the curriculum. The questions
are 1) how much design should be required, and 2) how does one define "design"? In order to air these
important questions, CEE is publishing the following two papers. Additional comments are solicited
from our readers.


J views and opinions


ARE WE PARTICIPANTS OR VICTIMS?

JAMES WEI
Massachusetts Institute of Technology
Cambridge, MA 02139


T HIS CONVERSATION, or something like it, took
place at the San Francisco AIChE meeting
among a group of distinguished professors and
department chairmen of research universities.
"They are making a mess at accreditation (or
choose one from: AIChE, NSF, ACS, ASEE,
NAE, etc.). They are just a bunch of bean count-
ers who do not understand that we should have in-
novations and diversity. And besides, who are
they to tell us that our program is below stand-
ards? Have they ever managed a first-rate depart-
ment themselves?"
"Why don't you do something about it, suggest
changes, organize a group, get involved?"
"I am much too busy with my students and
papers. Somebody else should do it." (i.e., some-
body else not as good as we are, say a politician
who cannot hack it in research and teaching.)
"But these are our own organizations that we
depend on. If we won't fix them, who else would
do it?"
"We can send them an ultimatum, that if they
do not shape up, we will quit."
"We need to send them a detailed blueprint
on how to reform their rotten organization. And
if they cannot do it, we will have to start a new
organization to administer accreditation, to set
up new rules, to train new visitors, and to evaluate
results. That would be even more work than re-
form from within."
"Of course not, that would take too much time
and effort."
"You are mad enough to complain, but not
enough to do something constructive-like volun-
teer for service. Shouldn't we take the time to fix
up our own organizations? No one else would
have the knowledge or motivation to fix them to


James Wei received his BChE from Georgia Tech in 1952 and
his ScD from M.I.T. in 1955. He graduated from the Advanced Man-
agement Program at the Harvard Business School in 1969. He is
presently Warren K. Lewis Professor and Department Head at the
Massachusetts Institute of Technology.

our specifications."
"But that would be politics."
"For instance, the AIChE Council of 17 con-
tains only two professors. The accreditation com-
mittee and the ad hoc visitor list have very few
professors from research universities. We believe
in a trial by a jury of peers, and our peers are
other research universities. If we will not sit on
juries, we cannot be tried by a jury of peers-who
understand us and are sympathetic to us. We
should run for AIChE Council, or volunteer for
ad hoc visitor in accreditation."
"I am much too busy, and I am not interested
in politics."
"But politics affects us, and it has us riled up.
If we are above politics, would we rather be
victims or participants?"
"Let us go to the Exxon suite to drown our
sorrows."
The moral of the story is that it is better to
be mugged than to participate in government, or
isn't it?

Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION








Classroom


THE TEACHING OF PROCESS DESIGN


EDITOR'S NOTE: The following paper, authored by the late T. K. Sherwood in 1959 while he was
a faculty member at M.I.T., was sent to CEE by W. H. (Bill) Manogue, a member of the AIChE Educa-
tion and Accreditation Committee. He credits E. L. Mongan, Principal Division Consultant in Du Pont's
Engineering Service Division, for bringing it to his attention.
Professor Emeritus J. Edward Vivian of M.I.T. has written Dr. Manogue that he and Professor Wei
(Head, Department of Chemical Engineering at M.I.T.) have reviewed the manuscript and "while he
agreed with me that Sherwood's conclusion is not current, he felt that as long as the publication ap-
peared with an Editor's note that this was a historical paper written in 1959, he had no objection to


publication of the complete original manuscript."
We are pleased to be able to share this historical
above.

T. K. SHERWOOD (Deceased)
Former professor at
Massachusetts Institute of Technology
Cambridge, MA 02139

T IS SUGGESTED that engineering design can be
taught effectively by introducing design prob-
lems into various theoretical subjects. A sample
thermo problem is presented in detail as the best
means of explaining just how this approach can
be used in a course such as engineering thermo-
dynamics.
If this technique is to be more generally em-
ployed at M.I.T. it is necessary that a large
fraction of the engineering faculty be as inter-
ested and competent in the design aspects of
engineering as they are in the scientific or an-
alytical. The fraction so inclined is perhaps al-
ready too small and appears to be decreasing.

INTRODUCTION
The typical engineering accomplishment of
importance results from a sequence of (a)
recognition of a social need or economic oppor-
tunity, (b) a conception of a plan as to how the
need may be met or the opportunity seized, (c)
an analysis of the merits of the conception and
of the consequences of proceeding with the plan,
(d) the building or construction of the machine,
plant or bridge as conceived, and (e) its opera-
tion. Item (c) is a sort of go no-go step; if the
Copyright ChE Division, ASEE, 1985


document with our readers, with the comments


analysis is discouraging, the conception step and
the analysis are repeated.
"Engineering science" is a phrase which has
come into use in recent years to describe the
analysis step. Good engineers today must be ex-
ceedingly proficient in analyzing a concept;
quantitative mathematical analysis based on first
principles is one of the good engineer's most
powerful tools. But it no more constitutes engi-
neering than any one of the other four activities
listed. In particular, it must be noted that con-
ception ("design") comes before analysis; the
analyst must have something to analyze.
As technology develops, it seems likely that
those engineers who can recognize social needs
or economic opportunities and who can conceive
and plan will be the men most sought after. They
will be the ones who will hire the analysts (engi-
neering scientists), the constructors, and the
operators. To a large degree this is true today.

THESIS
The concept ("design") abilities of the
student may be developed in at least three ways:
(a) through design courses, planned to meet
the need directly through lectures and exercises
(this is the method used in architecture), (b) by
subjects in which design problems are inter-
woven with the teaching of basic theory, and (c)
by sticking to basic theory and the techniques of
analysis, letting the student develop his own skill
at inventive and conceptual thinking by exposure


SUMMER 1985









The teaching method I have
in mind is best understood by studying
an actual problem assignment. The example chosen
is from engineering thermodynamics.

to the ideas and accomplishments of the great
creative scientists.
The teaching of design by method (a) has not
been well developed, except in connection with
machines, aircraft, and architecture. Method (c)
offers little promise for engineering. My thesis is
that the second method can and should be more
widely used in engineering education.

EXPLANATION
The teaching method I have in mind is best
understood by studying an actual problem assign-
ment. The example chosen is from engineering
thermodynamics, partly because I teach this sub-
ject, but also because thermodynamics is one of
the best examples of a subject that is often taught
with no element of engineering design. It is a theo-
retical subject involving many abstract ideas and
is normally expected to require rigorous thinking
and exact calculations.

ILLUSTRATIVE PROBLEM
The following is a typical problem assign-
ment to juniors about the middle of the first term
of a two-term course in chemical engineering
thermodynamics.
*s

Problem 10
A gas well in New Mexico produces essential-
ly pure CO2 at 800 psia and 100'F. The pressure
is reduced to 200 psia by flow through a partially
closed ("cracked") valve and delivered by pipe
line to a plant several miles away. The flow rate is
steady at 10 million ft3/day (reported as ft3 at
60F and 1.0 atm).
The Joule-Thomson expansion through the
adiabatic valve causes the gas to cool. This cold
gas is used to provide refrigeration for a natural
gasoline plant located near the wellhead. The con-
denser to be cooled operates at 60F, and the
minimum temperature difference for heat ex-
change is 5F (i.e., the warmed CO2 leaves at
550F).
a) What is the temperature of the CO2 leav-
ing the valve?


b) What is the attainable refrigeration load,
expressed as BTU/hr?
(Comment-note how the instructor has made
this sound like a practical problem by the word-
ing. This is pure camouflage-the solution is
simple and straightforward. The student is not
asked to think-only to know how to use the first
law and the Mollier diagram for CO,.)

Solution
From the book, the first law flow equation is
found to be
Q-W,, = Ah
As applied to an adiabatic valve Q and W,
are zero, so the enthalpy leaving the valve is the
same as upstream. This is read from the Mollier
diagram to be 146 Btu/lb CO,. At 200 psia CO,
has this enthalpy at 5F, which is the answer to
(a).
At 55F and 200 psia the enthalpy is 158 Btu/
lb, as read from the chart. In the condenser Ah is
158-146 or 12 Btu/lb CO,. From the first law flow
equation as applied to the condenser
Q -0 = Ah
so the refrigeration amounts to 12 Btu/lb CO2
flowing.
The specific volume of CO, at 60F and 1.0
atm is read from the chart as 9.2 ft3/lb, so the
CO, flow rate is
10,000,000/9.2(24) = 45,300 lb/hr
The refrigeration load is then
45,300(12) = 543,000 Btu/hr
This is the answer to (b).
*

USE OF THE PROBLEM TO TEACH DESIGN
Now consider the problem so reworded as to
invite the student to look at the design aspects of
the situation.
The CO, flow rate is specified to be the same
as before. The pipe line pressure is 200 psia, as
before. Cooling water is available which can be
used to cool the CO2 stream to 700F. The condens-
er to be cooled now operates at 20F; the cold
gas can be warmed only to 150F so as to maintain
the minimum temperature difference of 5F.
The student is now asked: how much refriger-
ation is attainable from the CO2 stream? How
would the necessary equipment be arranged (i.e.,


CHEMICAL ENGINEERING EDUCATION









draw a flow sheet)?
The routine M.I.T. "A" or "B" student sees the
statement regarding available cooling water,
notes that the feed gas is the only thing capable
of being cooled to 70F, and so refigures the prob-
lem with gas entering the valve at 70F and 800
psia.
Enthalpy values from Mollier chart: feed gas,
146; gas at 800 psia, 70F, 126; gas at 200 psia,
150F, 148. Refrigeration is then

45,300(148-126) = 1,000,000 Btu/hr
and
45,300 (146 126) = 906,000 Btu/hr

are removed by the cooling water. The flow sheet
is shown in Fig. 1.

COOLER CONDENSER
FEEDVALVE 15
EGAS I

100 WATER 20F

FIGURE 1

A second student, probably a "B" or "C" man,
goes through this same calculation, but in doing
so notices that the CO, leaving the valve is
partly liquefied. This is evidently a good thing. If
all the CO2 could be liquefied, there would be a
very large amount of refrigeration. But avail-
able cooling water limits cooling to 70F. The
chart shows that CO2 could be liquefied at 70F
if the pressure were about 865 psia. The well
pressure is only 800 psia. But it should not take
much power to compress the feed gas to 865 psia;
the pump might be expensive because of the high
operating pressure, but would be physically small
because the gas density is high and the volu-
metric displacement low.
The second student's flow sheet is shown in
Fig. 2. The compressor is assumed to operate
adiabatically and reversibly, and the pressure
change is assumed to be isentropic. The first law
gives the flow work as -Ah, which is read from
the chart as approximately 2 Btu/lb. The theo-
retical power required is
45,300 (2)/3412 = 26.7 kw or 35.6 hp
which does not seem like much.
The CO2 now leaves the cooler completely
liquefied at 700F with an enthalpy of only 65
Btu/lb. Ah is zero through the valve, so the re-
frigeration attainable in the condenser is
45,300 (148- 65) = 3,760,000 Btu/hr


COOLER CONDENSER
COMPRESSOR VALVE 1


FEED
GAS
800 psia
FIGURE 2

The student does not know much about the
efficiency or cost of compressors, but he concludes
that even if the actual power were twice the theo-
retical, the compressor installation would appear
to be well worth while in view of the very large
increase in refrigeration attainable.
A third student follows the same reasoning
and makes the same calculations as the second,
but is troubled by the fact that the chart gives
extremely poor precision in reading the Ah of 2
Btu/lb in the compressor. He has learned that if
kinetic and potential energy terms are neglected,
Ah for reversible flow is given as

fvdp

Reading the chart, he finds the specific volume

HEAT
COOLER EXCHANGER ALIVE CONDENSER
COMPRESSOR -VALVE
200 psa
FEED
GAS
65'F
GAS TO
PIPELINE
FIGURE 3

of the feed gas to be 0.115 ft3/lb and that of the
gas compressed isentropically to 865 psia to be
about 0.105. An average value of 0.11 ft3/lb
cannot be more than 5% in error, so

Ah = 0.11(865- 800) (144/778) = 1.32 Btu/lb

from which he calculates the theoretical (adi-
abatic reversible) compressor power to be 17.5
kw.
A fourth student makes the same calculations
as the second or third student, but hates to see
the gas go to the pipe line at 15F. Cannot this
cold gas be useful? Water cooling to 70F certain-
ly was. Using the cold gas to partially cool the
feed gas would only save cooling water. The thing
to do, then, is to use the 15 gas to cool the liquid
CO, leaving the gas-water heat exchanger. His
flow sheet is shown in Fig. 3.
Continued on page 164.


SUMMER 1985









) P.1 laboratory


A JUNIOR YEAR CHE LABORATORY


W. R. PATERSON
University of Cambridge
Cambridge, England CB2 3RA

SOME EXPERIMENTS which the author ran in
1980-81 in the University of Edinburgh's
third year chemical engineering laboratory are
shown in Table 1. Fluid mechanics and thermo-
dynamics laboratories are taken separately. This
is the major chemical engineering formal lab,
since the student does research and design pro-
jects in the fourth year of the course. The students
work in pairs, starting at 10:00 a.m. and finish-
ing nominally at 5:00 p.m. (in practice, between
about 3:00 and 6:00 p.m.). The lab runs for two
terms. In the third term of the session the weekly
lab is omitted and there is a 'lab week' instead
where the students devote the whole of one week
to an open-ended short project, such as the de-
velopment of a new lab experiment. This paper
remarks on features of the experiments which
might make them attractive for wider use.

CONVECTIVE MASS AND HEAT TRANSFER
Good convective mass transfer experiments
are hard to find. This writer's experience with
wetted wall columns, for instance, has not been
happy. The purpose of this experiment is not the
study of simultaneous heat and mass transfer,
but the study separately of convective heat and
mass transfer in the same geometry, to allow the
j-factor analogy to be confirmed. The apparatus
was originally a commercial heat transfer experi-
ment, consisting of a 12.5 cm square duct with a
perspex test section, through which air is drawn
by a blower. Transverse rods of 1.25 cm diameter


The purpose of this experiment is not
the study of simultaneous heat and mass transfer,
but the study separately of convective heat and mass
transfer in the same geometry, to allow the
j-factor analogy to be confirmed.

Copyright ChE Division, ASEE, 1985


TABLE 1
LIST OF EXPERIMENTS (1982)
Topic: Principal Measurement Method; Ancillary
Equipment
1. Plate Heat Exchanger: Thermocouple
2. Film and Nucleate boiling: Thermocouple; Ammeter
3. Double Pipe Heat Exchanger: Thermocouple; Weigh
Tank
4. Single Tube Condenser: Thermometer
5. Heat Transfer to a Jet: Liquid Crystal Sheet
6. Jacketed Pans: Thermometer; Weigh Tank
7. Process Control: Float; Micro-computer
8. Convective Mass and Heat Transfer: Balance, Thermo-
couple; Chart Recorder
9. Continuous Still: Densitometer
10. Continuous Liquid-Liquid Extraction: Titration
11. Drying: Continuous Weighing; Anemometer
12. Filtration: Volumetric Cylinder; Filter Leaf
13. Packed Tower Hydraulics: Manometer
14. Fluidised Beds: Manometer; Weigh Scales
15. Diffusion-Closed System: Gas Liquid Chromatography;
Recorder and Integrator
16. Diffusion-open system: Katharometer; Chart Recorder
17. Measurement of Surface Area of Alumina: B.E.T. Ap-
paratus; Liquid N2
18. Packed Bed Catalytic Reactor: Gas Liquid Chroma-
tography; Recorder and Integrator
19. Adiabatic Batch Reactor: Thermocouple; Micro-com-
puter
20. Enzyme Catalysis: Polarimeter
21. C.S.T.R.: Spectrophotometer
22. Residence Time Distribution Study: Flame lonisation
Detector; Micro-computer
23. Coagulation: Pressure Transducer; Chart Recorder


are introduced through holes in the wall, to simu-
late up to four rows of a heat exchanger tube
bank: all the rods but one are perspex dummies.
The working rod is copper and has a thermo-
couple within it. This rod is heated electrically
and then inserted into place at the start of the ex-
periment. From its cooling curve the gas-rod heat
transfer coefficient is deduced, and the experi-
ment is repeated for different air velocities and
test-rod positions. Measured pressure drops are
also logged. Next, the mass transfer runs are per-
formed.
The adaption to mass transfer work exploits


CHEMICAL ENGINEERING EDUCATION








method are reported elsewhere [3, 4].


HEAT TRANSFER TO A JET


Bill Paterson lectured at Edinburgh after taking his BSc and
PhD there. He has been a development manager with I.C.I. Petro-
chemicals Division and is now a University Lecturer in chemical
engineering and Director of Studies in chemical engineering at Corpus
Christi and Sidney Sussex Colleges, Cambridge. His research interests
include chemical reaction engineering, packed bed operations, flow-
sheet simulation and process synthesis.


Macleod's swollen polymer method [1, 2]. A thin
film of commercial silicone rubber is deposited on
the surface of the mass transfer working rod.
This is swollen to equilibrium with some suitable
volatile agent, e.g. ethyl salicylate. When the rod
is placed in the air stream the agent evaporates.
There is a constant rate drying period during
which the partial pressure of the swelling agent
immediately above the polymer is sensibly con-
stant, equal to its saturated vapour pressure at
the air temperature, and the controlling mass
transfer resistance is rod-gas convection; diffu-
sion through the polymer does not intrude. Inter-
mittent withdrawal and weighing of the rod both
establishes the mass transfer rate (and thus the
mass transfer coefficient, for the partial pressure
of swelling agent in the bulk gas is virtually zero)
and confirms that the test is within the constant
rate period. The rod can then be immersed in a
test-tube of swelling agent for re-swelling to
equilibrium, while a different test rod, ready pre-
pared, is used for the next run. Since saturated
vapour pressure is sensitive to temperature, it is
important to measure the air temperature with
more accuracy (e.g., 0.1C) than the heat
transfer experiment requires.
The transfer coefficients are then nondimen-
sionalised, to show that the restricted j factor
anology, j, = jH, holds, while the presence of form
drag falsifies the complete j factor analogy jD =
JH = f/2, where f is the friction factor. Alterna-
tive swelling agents, appropriate values of satur-
ated vapour pressure and diffusivity, and other
simple experiments using the swollen polymer


A flat horizontal sheet of plastic, of area A,
incorporating a commercial liquid-crystal temp-
erature-sensitive film, is heated from below by
direct contact with an electric heating mat. The
relation between sheet temperature and colour is
established in preliminary experiments. The mat
sits on insulating material so that all its power,
W, measured as current times voltage, passes
through the sheet. The sheet quickly reaches a
thermal steady state, so that, in still air, it has
a uniform colour. A round, laminar air jet is then
aimed at the centre of the sheet, normal to its
surface. Then, since the solid-air heat transfer


Good convective mass transfer
experiments are hard to find. This writer's
experience with wetted wall columns, for instance,
has not been happy.


coefficient, h, varies with position, r, so does the
surface temperature of the film, Ts, and coloured
rings appear on the film. The heat transfer co-
efficient, as a function of r, is calculated from
h(r) = W/A[T-T,(r)]
and compared with theory [5]
Nu(r) = 0.159 Prl/Rea/4(d/r) 5/4
where d is the diameter of the jet.
The experiment is repeated with a square jet
for which no theory exists, and the students ex-
plore the unexpected and interesting results. An
improved and abbreviated (two hour) form of
this experiment has been transplanted to the
second-year fluid mechanics and transport pro-
cesses lab in Cambridge. Details may be had by
writing to Mr. N. MacFadyen.

DIFFUSION EXPERIMENTS
Usefully accurate gas diffusivity measure-
ments can readily be made in a Stefan experi-
ment [6] where evaporation rates are measured
from a long-necked flask. However, this experi-
ment does not involve the direct measurement of
concentration profiles and is consequently found
unsatisfactory by some students. The two ex-
periments used in this lab are selected to remedy
this defect, to show the difference between equi-
molecular counter-diffusion and diffusion through


SUMMER 1985








a stagnant film, and to introduce the student to
some moderately heavy mathematics and to some
analytical instruments.
The counter-diffusion experiment is Cover's
[7]. About 5 ml of, e.g., acetone vapour is injected
through a septum near the bottom of a vertical,
lagged sealed glass tube (length ca. 60 cm, i.d.
2.5 cm) containing, as host gas, nitrogen traced
with 3% ethane. A subsequent series of analyses
of samples withdrawn (by 100 [l gas-tight
syringes) at two sample points each located at
one-sixth of a tube length from an end permits
determination of DAB, the diffusivity of the va-
pour in nitrogen. The acetone concentration in
counter-diffusion is described by the diffusion
equation (Fick's second law)
DCQ DAB 3Z,
at DZ2
with t = 0, CA(Z) = CAO(Z)
Z = 0,L, ?CA/DZ = 0
where Z is the axial coordinate, t is time, and
L is the tube length. The solution for t > 0 is
obtained by separation of variables

CA(Z,t)=Ao+ Ak exp k DAt cos kZ
k=l L L
where the values of the coefficients Ao A. de-
pend on the initial concentration CA(Z), that
is, on the particular Z-wise concentration profile
set up on completion of injection (t = 0).
Taking the difference of concentration be-
tween two points at the same time, the even
terms cancel and the odd terms double. The lo-
cation of the sample points causes the term in A,
also to vanish, while the decaying exponential
factor causes the terms in A, and higher to be
negligible for all but the shortest times. Hence
[CA(1/6 L,t) -CA(5/6 L,t)]
is proportional to

exp[- -Z DABt]

Thus the slope of a plot of the logarithm of
that concentration difference against time yields
DAB. The unknown and unimportant A1 is includ-
ed in the intercept. Since a difference in vapour
concentration is required, considerable error
would result if the sample volumes were not
identical. The purpose of the ethane tracer is to
permit correction for differing sample volumes
by use of the areas of the ethane peaks from the


GLC. Note that calibration of the GLC is un-
necessary so long as peak area is proportional
to the moles of species in the sample, since ace-
tone peak areas (corrected using ethane peak
areas) may be used in place of molar concentra-
tions in the difference term above: the intercept
of the plot changes, but not its slope.
The stagnant film experiment is Crosby's [8].
Here the film is arranged to be very thick-it
occupies a diffusion cell about 0.4 m high. A pile
of discs with a hole in each is assembled on a
central pivot and can be arranged so that the holes
are in line to form a vertical tube. At the bottom
a reservoir carries a volatile liquid, e.g., acetone.
At the top a cap has a stream of nitrogen flowing
through it. It is assumed that the concentration
of vapour at the bottom is due to the vapour pres-
sure at room temperature; at the top it is always
zero. Starting with nitrogen only in the system,
vapour is allowed access at zero time. At any sub-
sequent time, t, vapour will have diffused towards
the top. At time, t, alternate discs are rotated to
isolate each section of the cell. A stream of nitro-
gen is used to flush out each section in turn and
a quantity proportional to the vapour mole frac-
tion is determined by a thermal conductivity cell
katharometerr) attached to a chart recorder. The
shape of the vapour concentration profile is thus
established.
The only important modification from Crosby's
design is that 'O'-rings were recessed into the
horizontal faces of the dural discs to seal them
adequately. The mathematics is laid out in BSL
[9]. In contrast to the 'long time' analysis above,
the analysis here is for 'short' times so that there
is no breakthrough of acetone into the top cell.
Then a semi-infinite boundary condition is used
(Z = co, CA = 0), and solution is effected by
Boltzmann's transformation or by Laplace trans-
form. The text is careful to draw attention to the
error which could occur by naive application of
Fick's second law. The measured value of diffu-
sion coefficient may be compared with that from
the experiment above.

ADIABATIC BATCH REACTOR

An exothermic batch reaction is performed
batchwise in a stirred Dewar flask, with progress
followed by measurement of temperature, as de-
scribed by Williams [10]. However, in addition
to the reactions he recommends (sodium thiosul-
fate with hydrogen peroxide, and acetic anhy-


CHEMICAL ENGINEERING EDUCATION









dride hydrolysis), there is provision for study of
the acid-catalysed hydrolysis of propylene oxide
to the glycol [11]. Assuming that this reaction is
pseudo zero order in H20, which is in great excess,
and nth order in propylene oxide, the heat and
material balances yield the variation of tempera-
ture T with time t

1 dT C0 )-1 Aexp(-E/RT)
(Tf-T)" dt \T,-

where subscripts f and 0 imply final and initial.
For an assumed value of n, the values of the pre-
exponential factor, A, and the activation energy,
E, may now be estimated either by (a) numeri-
cal/graphical differentiation of the measured T
vs t curve followed by plotting the logarithm of
the L.H.S. versus 1/T [10] or (b) by a numerical
integration method [11] in which experimental
errors tend to be cancelled rather than amplified.
Both of these methods are readily programmed
for the microcomputer which logs the T vs t
curve (receiving a thermocouple signal ampli-
fied and digitised by a DVM). Also programmed
is an ordinary differential equation (o.d.e.) inte-
gration routine which permits integration of the
o.d.e. above with the estimated values of A and E
and the assumed value of n. Thus the student can
plot the predicted T vs t profile to compare with
the experimental values, and choose the value of
n (from, say, 0, 1/2, 1, 2) which gives the best fit.
It is also possible then to predict profiles for
different initial concentrations (Co) or tempera-
(To), and so to find initial values which will lead
to very different predictions of the profile for
different assumed values of n. A second experi-
ment allows easy discrimination of the best value
of n [11].
A particular advantage of this reaction is that
the order of reaction with respect to catalyst con-
centration, CH+, is easily found. From the o.d.e.,
writing A'CH+m for A,

Ti
dT
J (Tf-T) exp(-E/RT)
To
ti

Sf T A'C11 dt
(
0


( (o n-1 A'CH m t1
Ti To


Consider two runs using different values of CH+
but the same initial values Co, To, and hence the
same final temperature Tf. Choose some con-
venient intermediate temperature Ti and note
the corresponding values of ti for the two runs.
Now, the LHS is the same for both runs. So
(CH.+ ti)
is constant too, so that the two pairs (CH+, ti) im-
mediately yield the value of m. As far as is
known, this result is new. The values of n, m,
E, A' obtained agree well with the literature
[11, 12].

NOTES ON OTHER EXPERIMENTS
The packed tower hydraulics experiment is a
conventional study of loading and flooding in two
six-inch diameter towers, one packed with
Raschig rings and the other with glass helices.
However, it has one pleasing feature: the first
tower floods first at the top, followed by the flood-
ing moving downwards, whereas the second floods
at the bottom and the flooded zone grows up-
wards. The cause of the former is presumably
that the gas volumetric flow is highest at the top:
of the latter, that the helices compress readily,
so that the bed voidage is least at its base and
resistance to flow is highest there. A remarkable
number of students don't notice.
The packed bed catalytic reactor is used to
study the dehydration of 2-propanol to a mixture
of propylene and di (2-propyl) ether over an
alumina catalyst: this reaction is only mildly
endothermic so that reactor isothermality may be
assumed, the reactor and the feed preheater being
in an oven. Catalyst particles are so small that
pore diffusion limitations do not occur.
The enzyme catalysis experiment is performed
in a batch reactor made by modifying a spinning
catalyst basket reactor of the Carberry type.
Glucose is converted to fructose by an im-
mobilised enzyme "sweetzyme Q" manufactured
by Nova A. S. of Copenhagen, used at 60C and
pH = 8.5. The constants in the Michaelis-Menten
kinetic expression are determined. The rotational
speed of the basket can be varied from run to run
to permit investigation of external mass transfer
effects. El

ACKNOWLEDGMENT
This lab was assembled as a team effort, so
Cnotinued on page 160.


SUMMER 1985









curriculum


BASIC INFORMATION SCIENCE TRAINING

FOR CHEMICAL ENGINEERS*


0. M. KUT1, R. QUERALT2,
AND L. M. ROSE1
1Swiss Federal Institute of Technology (E.T.H.)
Ziirich, Switzerland.
2Instituto Quimico de Sarria, Barcelona, Spain.

ITH THE INCREASING amount of published in-
formation and improved methods of assessing
this information, there is a new awareness within
chemical engineering that systematic information
retrieval from the literature is an important start-
ing point for any type of project. To match this
awareness (already prevalent in industry),
chemical engineering courses should include some
instruction in the subject of information science.
There is more to information retrieval than
simply knowing where the library is and knowing
how to use an index. It is possible to give students
a more thorough background in information
science in a comparatively short course-if it is
well organised. The objective of this paper is to
indicate the possible contents of such a course and
to relate some experiences already gained in teach-
ing the subject to chemical engineering students.

COURSE OUTLINE
A modern information and documentation
course for chemical engineers should cover print-
ed bibliographic information, numerical data, and
methods of computer retrieval, both of numerical
and bibliographic data.

Available Printed Information
Traditional literature searching has always
concerned itself with searching the scientific
journals-the primary publications. Since chemi-
cal engineering is a mixed discipline, it is often

*This paper was commissioned by the European Federa-
tion of Chemical Engineering, Working Party on In-
formation and Documentation.


The objective of this paper
is to indicate the possible contents
of such a course and to relate some experiences
already gained in teaching the subject to
chemical engineering students.

worthwhile to look in other specialized areas for
relevant material-statistics, operations research,
chemistry, mechanical engineering, computing,
and electrical engineering all overlap with various
chemical engineering subjects, particularly at the
research level.
Primary literature goes beyond the published
journals; conference pre-prints, dissertations, and
patents all belong to the primary literature, but
are more difficult to obtain than the international
journals. The difficulty in obtaining these very im-
portant publications is overcome by the develop-
ment of the secondary publications.
The secondary publications are abstracts of
the primary literature, the most famous of which
is Chemical Abstracts. Chemical Abstracts is so
important to the chemical engineer that he should
be able to use it without difficulty, understanding
the concepts of its indexing and registry numbers
for components. Chemical engineering has some
lesser known abstracts of its own: Theoretical
Chemical Engineering Abstracts (POB 146, Liver-
pool, England), Chemical Engineering Abstracts,
(University, Nottingham, England), and DE-
CHEMA, (PF 970 146, D-6 Frankfurt-97, W.
Germany). Abstracts in overlapping fields
(INSPEC for mathematics and control, Engineer-
ing Index for heat exchange) can also be useful.
Under secondary publications one can also list
the Science Citation Index (SCI) which enables
forward searches to be made, and the ISI weekly
publication of contents pages of the scientific
journal, Current Contents, enabling the contents
of most of the recent journal issues to be effective-
Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION


__


I


i


BBSChE









ly followed.
Finally there is the tertiary literature. This
is an organised summary of the literature in each
particular field: handbooks, monographs, data
collections, and textbooks. Perry is, of course, the
most important. Then there are the encyclo-
pedias of chemical technology of Kirk-Othmer and
Ullmann.
Numerical data are very important to the
chemical engineer, and these are generally found
in the tertiary publications. General data con-
cerning chemicals are best covered by Beilstein
(organic) and Gmelin (inorganic). Though both
these works were in German, new editions are
now in English. Other publications concentrate
on particular properties.
Finally there are the monographs and text-
books. They often provide an excellent starting
point for any search by summarizing the particu-
lar technology up to a certain point in time-which
is often adequate for the needs of many problems.
The graduating chemical engineering student
should be aware of these facilities in his library.
He should be able to carry out searches in Chemi-
cal Abstracts, know where to obtain numerical
data, know how to use the subject and author
catalogues in the library, and know that the li-
brarian is a trained professional, there to help
him when he has difficulties.

Computer-Stored Information

Bibliographic Data Bases: The history of the
development of computer readable bibliographic
data bases is a fascinating opening to the subject


Oemer Muhan Kut received
his M.Sc. and Ph.D. degrees in
chemical engineering from the
Swiss Federal Institute of
Technology (ETH) in Zurich.
Since 1972 he has been a re-
search associate at ETH. His
major research interests are in
the areas of applied catalysis,
catalytic reaction engineering,
and modelling of multiphase
reactors. (L)
Rafael Queralt received his
diploma in chemical engineer-
ing from IQS and since 1963
has been an assistant professor at the Instituto Quimico de Sarria.
He is also head of the Library and Documentation Services at IQS,
which is a pioneer centre of automized chemical information in Spain.
(C)
L. Murray Rose has a B.Sc. and a Ph.D. in chemical engineering


of the production of SDI (Selective Dissemination
of Information) tapes. To rationalize the pro-
duction of the printed abstracts, the total ab-
stracts were coded onto magnetic tape. It was then
a small step to the distribution of these tapes to
institutions wishing to perform their own
searches electronically rather than waiting for
the printed versions to be posted and going
through them manually!
It is interesting for most chemical engineers
to know the principles on which the computer
searching is done. The availability of the ab-
stracts on tape, the need to have a thesaurus and
to invert the SDI tapes to be able to recover
which abstracts refer to each particular keyword
are important points to explain in the course.
There is a growing feeling among informa-
tion scientists that the engineer himself should
understand how computer searches are done. The
need to choose the individual keywords carefully
and to define a suitable search strategy, to know
the pitfalls of not including enough alternative
descriptions, and to know how to improve the
relevance by including further keywords. It is
particularly important that the chemical engi-
neer know which data bases are likely to be of
most use to him. Surveys in Europe have shown
Chemical Abstracts to be the most useful (al-
though it is far from ideal for most chemical engi-
neering problems). Chemical Abstracts needs
backing up with COMPENDEX or INSPEC,
where appropriate. Besides these three there are
many other data bases covering particular areas
of use to chemical engineers-part of the NIH-
EPA Chemical Information System for safety


from Birmingham University. Before joining the Systems Engineer-
ing Group of the Technical Chemistry Laboratory of the Swiss Federal
Institute of Technology (ETH) in 1971, he spent twelve years in in-
dustry. His efforts are toward instigating the sensible use of com-
puters in all branches of chemical engineering. (R)


SUMMER 1985









and chemical properties, DERWENT for patents,
PREDICAST for commercial information, DE-
CHEMA for equipment design and corrosion
problems, etc. The undergraduates should be
made aware of the scope and limitations of the
various fields.
It is also good for the undergraduates to be
informed on the component parts of the computer
literature searching system-the abstractors, the
files and inverted files, the hosts, the communica-
tions networks-that all need paying for every
character retrieved. And then, the multitude of
languages!
Numerical Data Banks: Parallel to computer
retrieval of bibliographic data, banks of physical
properties for use by chemical engineers have


The subject would be
given more status if it were a
short course in its own right, and not
simply squeezed into odd hours.

been developing and are now generally accessible
by any terminal connected to the telephone net-
work. Most normal chemicals in commerce
(-800) are now available on these banks which
store numerical physical property data, or use
predictive methods to give estimated values for
those not available. PPDS, EPIC and DECHEMA
systems are available in Europe, and PPDS in the
US.
For teaching purposes, a number of small
demonstration banks exist. CHEMCO is probably
the most widespread. There is no better way of
making a student realize that these modern tools
are available to him than to let him use them
during a design project.
Such data banks could be handled in an in-
formation and documentation course or in a
thermodynamics course, since they are excellent
for demonstrating enthalpies, chemical equilib-
rium, vapour-liquid equilibria (VLE), and equa-
tions of state. For them to be handled in both
courses would have the advantage of helping inte-
grate the whole curriculum.

SEARCH PROCEDURES
There are two fundamental types of litera-
ture searching
Retrospective searching, where a comprehensive
list of relevant literature published on a special
topic is sought


*Current awareness searching (SDI = Selective
Dissemination of Information), where the interest
concerns the current publications on the topic under
study.

The selection of information sources and the
mode of information retrieval will depend on the
type of search. For starting a systematic litera-
ture search, the problem and its limitations should
be clearly defined. In manual as well as in on-line
searches, the effectiveness of the study depends
on how well-prepared the search strategy is. To
get some experience in strategy preparation and
optimization, the library users should practice
manual searching techniques before starting on-
line searches.
A very useful start for undergraduate students
in chemical literature are small search exercises
in Chemical Abstracts using the printed indexes.
The user should become familiar with the Index
Guide and the Chemical Substance Index using
the Chemical Abstracts nomenclature. He should
also learn the concept and the limitations of the
Registry Numbers. These numbers, characteriz-
ing a single, well-defined chemical compound,
build a link between different bibliographic and
numerical data banks. The user should also prac-
tice how to select relevant keywords with all their
synonyms and truncations. He should also be
familiar with the linking concepts (and, or, not)
creating combinations of sets selected by the key-
words. For narrowing the search strategy the
user should also be aware of other possible limi-
tations such as language, document type, country,
or publication year.
Even with all these preparations, electronic
information retrieval continues to be a difficult
task for the average user without the assistance
of information specialists. For example, the
Chemical Abstracts (CA) SEARCH files are ac-
cessible from many host systems such as Lock-
heed, SDC, or Data Star. However, every host
system has its own software and its specific ad-
vantages and disadvantages, making different set
combinations and search strategies possible. The
fine structure of the programs are developing. An
average end-user making only a limited number
of on-line searches cannot be aware of all the pro-
gress made to reduce the search costs. Although
development in the direction of "user-friendly
systems" is progressing, at the moment the op-
timal combination seems to be co-operation be-
tween the information specialist who knows the
information systems and the end-user who knows


CHEMICAL ENGINEERING EDUCATION








the extent of his information requirements, so
that the on-line systems can be used efficiently as
an interactive system adapting the search strategy
to the given information. This need for teamwork
between the information specialist and the engi-
neer is ground enough for the undergraduate
engineer to be made aware of the principles of
information retrieval.

TEACHING EXPERIENCE
Experience in the Swiss Federal Institute of
Technology (E.T.H.)
In common with many other universities, the
time-table structure at E.T.H. makes it virtually
impossible to introduce new courses, so modern
methods of information and documentation have
to be squeezed into two hours borrowed from an-
other course, with practical exercises carried out
as part of a semester project. The introduction to
the semester project enables an additional two-
lecture-hours on manual searching to be given.
Because the particular semester project is con-
cerned with literature retrieval (four days), the
students get ample practical experience on manual
searching. The total of four lecture hours (which
includes a computer search demonstration) is not
really adequate to properly cover the material-
six to eight hours would be better. The four-day
manual search project is more than necessary for
the normal chemical engineering student. How-
ever, in the Technical Chemistry Department at
E.T.H. there is a strong emphasis on chemistry,
which is consistent with extended information re-
trieval exercises.
The subject would be given more status if it
were a short course in its own right, and not
simply squeezed into odd hours. This could con-
veniently be taught together with odd hours given
on communication (report writing, specification
writing, drawing standards, speaking and lectur-
ing) to provide sufficient material for an inde-
pendent course on communication.
Undergraduates do not carry out computer
searches, but postgraduates are allowed to carry
out some of the searches by computer in collabora-
tion with an information specialist.

Experience at the Instituto Quimico de Sarria
Since 1979 the Higher Technical Education
Centre for the formation of engineers has pro-
vided a course on Scientific and Technical Docu-
mentation for the fifth-year students (the last


Conferences

DESIGN CONFERENCE AT VPI
The ChE Department at Virginia Tech wishes to invite ChE edu-
cators to attend the Frank Vilbrandt Memorial Conference on Chemical
Process and Plant Design. The Conference is scheduled in celebration
of the 50th anniversary of the founding of the ChE Department at
Virginia Tech and will be held on October 10 and 11, 1985. Further
information can be obtained from Y. A. Liu, ChE Dept., Virginia
Tech, Blacksburg, VA 24061.


year of the chemical engineering curriculum). It
is compulsory for those students who opt for the
research course, at the end of which a Trabajo de
Fin de Carrera (final report on conclusion of
studies) has to be submitted before the degree
(in chemical engineering) can be awarded. It is,
however, optional for those students who do not
go for this research course and who will conse-
quently not complete their studies with this de-
gree.
The course is run for one week with two hours
every day, giving a total of ten hours for the
presentation of the various topics. The exercises
are done on an individual basis outside the regu-
lar course time, which means an average extra
time requirement of three hours for the practical
exercises. In the presentation of the material,
emphasis is put on practical application, the im-
portance of one-line systems demonstrated, and
extensive use of visual material like slides and
transparencies is made. The course contents are
remarkably similar to Table 1, which is the pro-
posed curriculum we are recommending.
The experience with this course during the
last five years has been highly positive. The
students have learned or improved their ability
to handle basic documentary sources (like Chemi-
cal Abstracts, Beilstein, Science Citation Index).
They know the possible ways of using information
media in their search for information, how to ac-
cess them, and finally, and this is very important,
they realize the complexity of the process for
searching for information and are aware of the
assistance available from the specialist in in-
formation and documentation.

COURSE CONTENTS
The European Federation of Chemical Engi-
neering has had a Working Party on Information
Continued on page 142.


SUMMER 1985










Classroom


IMPROVEMENTS IN THE TEACHING OF

STAGED OPERATIONS


MARYAM GOLNARAGHI,
PAULETTE CLANCY AND
KEITH E. GUBBINS
Cornell University
Ithaca, NY 14853

T HE USE OF COMPUTER graphics to aid and im-
prove the teaching of chemical engineering
principles is an area of growing interest. Many
topics have the potential to be greatly improved
by utilizing the special capabilities of computer
graphics, with rewards such as greater instructor
efficiency and additional aid for educationally
weaker students. One such topic is the teaching
of staged operations, usually conducted within a
separations course. For studies involving distilla-
tion-the single most important separation tech-
nique-the graphical method of McCabe and
Thiele [1] is typically employed due to its con-
ceptually simple formulation. However, the
manual calculation of a single McCabe-Thiele
plot for one case study is a lengthy and laborious
procedure, as any junior will attest! In order to


investigate the effect of different design param-
eters on the resulting column, this time-consuming
procedure must be repeated for each new case.
The repetition involved is of limited educational
value, yet it is most important that the student
have a firm grasp of the interrelationship be-
tween the various operating parameters, e.g., the
reflux ratio and the condition of the feed. The
usual result is that a severely restricted number
of cases can be studied, with additional limita-
tions on the complexity of the system. The results
of other interesting designs must be presented to
the student already complete, dulling the sense of
discovery that their investigation might have pro-
duced. Computer graphics offers solutions to
these problems, removing the burden of compu-
tational effort while preserving the simple graphi-
cal representation which allows a ready compre-
hension of the situation. These advantages were
recognized by Calo and Andres [2]. However, their
McCabe-Thiele package was devised around the
older technology of direct view storage tube
graphics, which is unsuitable for interactive use.


Maryam Golnaraghi is cur-
rently a Ph.D. candidate in the
Theoretical and Applied Me-
chanics Department of Cornell
University studying non-equi-
librium properties of granular
materials using statistical me-
chanics. She received her B.S.
degree in Chemical Engineer-
ing at Cornell in 1984. (L)
Paulette Clancy is current-
ly an assistant professor in
chemical engineering and as-
sociate director of the Manu-
facturing Program at Cornell
University. She received her BS degree at the University of London
and a D.Phil. degree at the University of Oxford. She held fellowships
at Cornell University and at London University before joining the
faculty at Cornell in 1984. (C)
Keith E. Gubbins is currently the Thomas R. Briggs Professor of
Engineering and director of chemical engineering at Cornell Uni-
versity. He received his BS and PhD degrees at the University of


London, and was on the staff at the University of Florida from 1962-
76, when he moved to Cornell. He has held visiting appointments at
Imperial College, London, at Oxford University, and at the University
of California at Berkeley. He has co-authored two books, Applied
Statistical Mechanics (Reed and Gubbins) and Theory of Molecular
Liquids (Gray and Gubbins). (R)
Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION










Computer graphics offers solutions to these problems, removing the
burden of computational effort while preserving the simple graphical representation which
allows a ready comprehension of the situation.


In the graphics package developed at Cornell,
the software was written for a sophisticated
vector refresh graphics workstation offering su-
perior interactive capabilities with virtually im-
mediate response to user-interaction. This pack-
age was implemented in the fall semester of 1984,
and will be used in our separations course.

DESIGNING THE PROJECT: HARDWARE
AND SOFTWARE
The Computer Aided Design Instructional
Facility at Cornell's Engineering School has been
described in an earlier publication [3]. Of the
graphics workstations available, a vector refresh
Evans and Sutherland Multipicture System was
chosen for this application since software ex-
pertise for this type of system was available with-
in the department. However, the nature of the
application is such that it could equally well have
been set up on a raster graphics system; indeed,
the programs have been structured for such a
change if necessary. User interaction with the
package was made possible largely through the
use of an electronic tablet and stylus (or pen),
with a VT100 terminal for alphanumeric input.
An electrostatic plotter was available for 'hard
copy' output of the contents of the screen, a use-
ful feature for the preparation of homework as-
signments.
As with the graphics package to represent
phase diagrams developed at Cornell [3], the ap-
pearance of this software package was carefully
conceived so that the design criteria given below
would be fulfilled in the most effective and invit-
ing fashion-in other words, in what computer
scientists like to call a "top-down" approach. The
objectives of the software package were
For a complete set of user-supplied variables de-
scribing the system, a McCabe-Thiele plot should
appear on the monitor's screen, together with a
scaled diagram of the resulting distillation column.
Interaction with the software package to change
any of the design parameters should be easily
effected and should produce an almost instantaneous
response in recomputing the McCabe-Thiele plot
and the design of the column, redisplaying them
on the monitor. This interaction should be designed
so that qualitative trends in column design result-


ing from parameter changes could be viewed almost
continuously if desired, or that specific values for
these parameters could be entered if a quantitative
calculation is required.
Extensive help must be available to aid the con-
fused, while the ability to restore the original screen
display is essential for the computationally en-
tangled. Instructive messages should appear on the
screen to inform the user of the program's status--
for example, if some unavoidable delay in process-
ing the input is about to occur.
The program must be structured in such a way
that its extension to more complex problems can be
incorporated into the existing software in a straight-
forward manner. Thus, some long-range planning
of the possible modifications to the package had to
be considered.
As far as possible the software produced should
be portable, so thought had to be given to pro-
ducing a machine-independent code. The decision
to write the software in FORTRAN, still the most
widely used high-level language in engineering,
stemmed from this desire.
Last, but still important, the programs should be
"bomb-proof," even for the most inventive student
user! The most likely input errors, or miskeying,
must be anticipated wherever possible.
Should these objectives not be met, resulting
in a final product that was difficult or frustrating
to use, much of its educational impact would be
lost. Such attention to detail in designing the ap-
plication graphics package is extremely time-con-
suming in terms of software development, but the
effort is amply recompensed once its use is es-
tablished as a regular component of the course.

THE INTERACTIVE McCABE-THIELE PACKAGE
We believe that the final product does indeed
meet the criteria given above, satisfying both the
instructor's and the student's differing needs. It
is a routine matter to produce numerical sub-
routines performing the calculations for the Mc-
Cabe-Thiele plots, but more time-consuming to
incorporate the graphics software to display an
aesthetically pleasing picture on the screen and
an ergonomically attractive interaction with the
displayed image.
The layout for the display is as shown in Fig.
1. The master object displayed consists of a Mc-
Cabe-Thiele plot with appropriate equilibrium
and operating lines and the "ladder" of stages.


SUMMER 1985








This is supplemented by a scale diagram of the
corresponding design for the distillation column
(relative to a six-foot tall 'stick figure' standing
beside it). Above these diagrams information
about the current values of the various operating
parameters is displayed, while the space below is
reserved for the "menu." The menu provides a
selection of options to enable the user to interact
with the viewed image. The user may select a par-
ticular option by moving the pen across and slight-
ly above the tablet until the cursor (in the form
of crosshairs on the screen) lies within the re-
quired area (or window) designated for this
option. Pressing the tip of the pen down in con-
tact with the tablet activates the window to per-
form a specific task.
The menu options for interacting with the
package are listed below (the window names are
in bold face type)
1. Six windows allow input of both the com-
position and the flowrate of the feed, distillate, and
waste product. The program will prompt the user
for values of any four independent variables from
these six in order to completely define the prob-
lem. Values are entered by placing the pen down
at some point within the window. Each window
contains a potentiometer which allows the value
of the appropriate variable to decrease or increase
as the pen is moved left or right across the
window. The value given by the current position
of the pen may be read in the area above the
diagrams.
2. When the calculate window is selected, the
program checks to see if the mass balance was
satisfied by the user-supplied variables. If the
mass balance was not satisfied the user is in-
formed and will be prompted to re-enter all four
values. In this way the programs assure that the
student is capable of performing the mass balance
correctly. Assuming all is well, a McCabe-Thiele
plot is produced for "start-up" values of the
operating parameters, e.g. the reflux ratio.
3. The user may now alter these operating
parameters by selecting appropriate windows for
the reflux ratio, operating pressure and heat per
mole of feed. Again, moving the pen along the
length of the window alters their respective
values with immediate response from the pro-
grams, producing altered images for the McCabe-
Thiele plot and column design.
4. If the user desires to set an exact value
for any variable this can be done using the key in
option. This offers an alternative to using the po-


FIGURE 1


tentiometers within the windows, which are
more suited to observing qualitative trends in the
behavior of the McCabe-Thiele plot. The 'key in'
feature prompts for numerical input at the VT100
terminal.
5. The reset window sets all the flowrates and
compositions to zero and the operating paramet-
ers (p, R and q) back to their initial preset values.
6. The window marked economical analysis
allows the user to determine the optimum value
of the reflux ratio in cost effectiveness. This will
be explained in more detail in the following
section.
7. Snap triggers the production of a paper
copy of the current screen contents on a nearby
plotter.
8. Help invokes the display of information
pertinent to the operation of each of the windows
in turn.
9. Exit halts execution of the program.

COLUMN DESIGN
The McCabe-Thiele method is widely used as
an educational tool in teaching distillation column
design at the undergraduate level, and details of
the method need not be repeated here. In the
existing version of the program, a single column
involving only one feed of a binary mixture of
components is considered. Extension of the pro-
grams to multiple feeds and sidestreams is under-
way. The feed may be introduced into the column


CHEMICAL ENGINEERING EDUCATION


F

0 e Rt









in any fluid condition (i.e., saturated liquid, sub-
cooled liquid, etc). Antoine's equation is used to
obtain the saturated temperatures and pressures
of both components, and the x-y equilibrium
curve is obtained assuming ideal behavior. Op-
tional consideration of a variety of non-ideal de-
scriptions of the equilibrium curve is also
possible.
Routines are included which calculate the di-
ameter and height of the distillation column for
each case study in order to produce the scaled
diagram described earlier, including the correct
number of bubble-cap trays, a total condenser,
reboiler, and the location of the feed tray. This
is achieved by following the recipe outlined in
Treybal [4].
Some interesting aspects of column design
with regard to the economics involved are also in-
corporated by allowing the preparation of a graph
showing the relationship between a given reflux
ratio and the total cost involved, considering both
capital costs and estimated running costs over the
expected lifetime of the column. The minimum
of this parabolic curve allows the estimation of
an optimum reflux ratio for the most cost-effec-
tive operation of the column.

SUMMARY
The implementation of the computer graphics
package described has proved to be of consider-
able assistance in the teaching of staged opera-
tions. Instructors benefit from the increased
quantity and complexity of problems which can
be investigated in the allowed time, and students
welcome this novel and easy-to-use tool which
makes completing their assignments so much less
onerous. D

ACKNOWLEDGMENTS
M. G. would like to thank C. D. Naik and G.
Charos for many helpful discussions. It is a plea-
sure to thank the Gas Research Institute for
practical support of this work.

REFERENCES
1. McCabe and Thiele, Ind. Eng. Chem., 17, 605 (1925).
2. J. M. Calo and R. P. Andres, Comp. in Chem. Eng., 5,
197 (1981).
3. C. D. Naik, P. Clancy and K. E. Gubbins, Chem.
Eng. Ed., 19, 78, (1985).
4. R. E. Treybal, Mass Transfer Operations, 2nd edition
(1968), McGraw-Hill, NY, p. 131-135, 142-144.


I letters

More on Tubular Flow Reactors
Dear Editor:
Professor Asfour's two improvements (CEE
XIX, 2, 84, 1985) to the original design of a tubu-
lar flow reactor using crystal violet dye and
sodium hydroxide reactants (Hudgins and Cayrol,
CEE XV, 1, 26, 1981) are timely ones. This ex-
periment, to judge from a recent survey (E. 0.
Eisen, "Teaching of Undergraduate Reactor De-
sign," AIChE Meeting, San Francisco, Nov.
1984), is now incorporated into several reaction
engineering laboratory courses in North America.
I welcome the occasion of the Asfour article
to suggest several additional improvements that
arise out of our experience since 1981.
First, I concur with the footnote in the Asfour
paper. Tygon tubing is an unhappy choice for
the tubular reactor. In our experience, clear Tygon
tubing darkens within a few hours' use to a per-
manent deep violet. This obscures the pleasing
axial color change that is one of the main at-
tractions of the experiment. Polyethylene tubing,
though translucent rather than transparent, re-
sists the crystal violet dye for a much longer
time.
Calculating the reactor volume can be a prob-
lem. Certainly, the nominal value of the inside
diameter of the tubing is not sufficiently accurate.
Some students have improved on this value by
trying to fit the tubing using indexed drill bits.
Because of the flexibility of the tubing, however,
it is not certain that the cross-sectional area re-
mains undistorted when the tubing is wound on
the large spool. Weighing the spool with the re-
actor tubing empty and then filled with water ap-
pears to be the most rigorous way to obtain the
volume.
In both of the above CEE articles, the spool
is shown mounted on its side. This has proven to
be an unfortunate method of mounting since
bubbles often enter the reactor tubing (perhaps
from the mixer pump), become trapped in the
coils of the tubing, and grow. An effective remedy
is to remount the spool with axis perpendicular
to the lab bench and flow spiralling upward. Of
course, this does not eliminate bubbles but does
prevent their retention and growth sometimes to
several percent of the total reactor volume.
Continued on page 161.


SUMMER 1985










SP laboratory


RECYCLE WITH HEATING

A Laboratory Experiment


A. FOORD AND G. MASON
Loughborough University of Technology
Loughborough, Leicestershire, England

SOME OF THE BASIC methods of chemical engi-
neering (heat and mass balances, for example)
have analogies (such as money) in everyday life,
and freshman students rarely have any con-
ceptual difficulty when such basic ideas are intro-
duced. However, when heat and mass balances
are combined with recycle, students often have
difficulty in analysing the process. They have diffi-
culty not so much with the heat and mass balances
themselves as with the whole concept of the re-
cycle process. This is mainly because there is no
immediate everyday counterpart, although an-












i-
Tony Foord received his BSc and PhD degrees in chemical engi-
neering at the University of Birmingham (England) and was sub-
sequently employed in research and development by the U.K. Atomic
Anergy Authority and by the Distillers Company in London in process
development and project evaluation. In 1966 he joined the faculty at
the Loughborough University of Technology. His teaching interests
have been process economics and chemical engineering calculations,
and his principal responsibility has been the overall management
and development of the undergraduate courses. (L)
Geoff Mason graduated in chemistry at the University of Bristol
in 1962. He then worked for his PhD in the physics department at the
University of Bath before returning to Bristol as a research fellow. In
1970 he joined the faculty at Loughborough where, apart from a year
spent at the Petroleum Recovery Research Center (New Mexico), he has
been ever since. His research interests are mainly concerned with the
capillary properties of porous materials, particularly pore blocking
and network effects. (R)


In order to aid the
understanding of recycle we have
devised a simple apparatus in which water is
heated in a recycle loop

alogies can be attempted with taxis and people.
In order to aid the understanding of recycle
we have devised a simple apparatus in which
water is heated in a recycle loop. When operated
in the steady state, the apparatus permits both a
visual and an experimental appreciation of the
operation of a simple recycle loop. Moreover, in
the unsteady state the apparatus has a response
time of ten minutes or so, and thus, transient be-
haviour can be followed easily. The apparatus is
relatively simple, and since it is built from do-
mestic plumbing pipes and fittings it has a
familiar and easily grasped appearance. It is
mounted on a wallboard so that the flow path can
be seen at once. It uses only water and electricity
as consumables.

APPARATUS
Fig. 1 is a schematic diagram of the appara-
tus. The recycle is driven by a domestic central
heating pump of the type used to circulate water
around radiators. Ours is an SMC Commodore
and it consumes about 150 watts. The heater is a
modified instantaneous shower heater, in essence
a copper can containing a 3kW heating element.
The shower heater originally had two in-built
safety devices, one a water pressure switch and
the other an anti-scald thermal cut-out. The heater
could only be activated when there was pressure
(and hence water) in the can and the tempera-
ture was below 500C. We modified our heater to
increase the cut-out temperature to 80C and re-
moved a flow constriction in the pressure-sensing
circuit.
The pump drives the recycle at up to 8 litres/

Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION








Q+q


FIGURE 1. Schematic diagram of the apparatus. The inlet flow, Q
(maximum 3 litres/min), is ordinary mains water. A recycle loop,
flow q (maximum 8 litres/min) is driven by a pump through a do-
mestic shower heater (3kW). The temperature of the inlet water, the
outlet water and just after the heater in the recycle loop, are all
measured.

min, the highest reading of the recycle rotameter.
There is a rotameter (3 litres/min maximum) on
the inlet side measuring the inlet flow of tap
water and an identical one on the outlet side.
Mercury-in-glass thermometers (although digital
devices would be better) are used to measure the
water inlet temperature, the temperature after
the heater in the recycle loop and the outlet
temperature. The water flow rate of the feed
and also of the recycle loop may be adjusted and
set by means of valves. The complete rig is il-
lustrated in Fig. 2.
The tube sizes, although apparently arbitrary,
make a difference to the performance of the ap-
paratus. Air comes out of solution in the heater
and tends to accumulate in the pump which is
working here at less than its design flow. By using
28 mm tubing at a slightly rising angle for the
top tube of the recycle loop and 22 mm tube for
the descending tube to the pump, the air tends to
enter the outlet pipe rather than be carried down-
wards. In the 15 mm sections air bubbles are
easily carried along, either upwards or down-
wards.

EXPERIMENTS
Steady-State
Mass balances: The first experiment is trivial
but is a graphic illustration of the mass balance
principle: at various valve settings it is easy to
show that whatever the recycle rate the inlet flow
rate always equals the outlet flow rate.
Heat balances: a) With the heater switched


T, = To + (H/QC)


where H is the combined heat input of the pump
and heater and C is the specific heat capacity of
water.
Similarly one obtains


T. = To + (H/QC) + (H/qC)


from a heat balance across the shower heater,
after eliminating T1 by means of Eq. (1).
So, by measuring the outlet water tempera-
ture, T,, as a function of the through flow rate,
Q, it is possible to determine the combined heat
input of the heater and pump by the use of Eq.
(1). The experiment takes some time to perform
because it takes about fifteen minutes for the
steady-state to be reached after a change in flow
rate. By plotting (Ti To) against 1/Q, the gra-
dient (H/C) gives the power input (H) as shown
on Fig. 3. Alternatively, Eq. (2) can be used. In


FIGURE 2. A photograph of the apparatus. It is mounted on a wall
board so that the flow directions are obvious. The top pipe is slightly
angled to assist in purging the air which comes out of solution as
the water is heated.


SUMMER 1985


on and at a fixed input water flow rate, the ap-
paratus shows that the outlet water temperature
is independent of the recycle rate. Students often
find this observation disconcerting. They observe
a change in the temperature of the recycle water
when its flow rate is altered, but find that the out-
let temperature of the loop remains the same.
Only when they consider the overall heat balance
do they find it obvious that the outlet temperature
is unaffected.
b) Using the variables marked on Fig. 1 for
flows and temperatures for the steady-state, a
heat balance over the whole system shows that












50-


40-
I--

r 30-

0
S20-

E
- 10-


0


Gradient = 45.9 degree.litres/min

Heater power = x 4.2
= 3,21 kW *





./ *

iS


0 0.2 0.4 0.6
I/Q min/I


1.0 1.1


FIGURE 3. Results from the steady-state operation of the apparatus.
The temperature rise of the through stream is plotted against the
reciprocal of the through flow rate. The graph is a straight line through
the origin with a gradient determined by the combined energy input
of the heater and circulating pump.


this case T2 is plotted against 1/q, where q is the
recycle rate, and H is obtained from the same
gradient. This latter method has the advantage
of actually making use of the recycle flow.

Unsteady-State

In unsteady-state experiments both the inlet
flow and recycle flow are fixed, the system is al-
lowed to approach, but not necessarily reach, equi-
librium, and the heater is switched either on or
off as appropriate. The apparatus takes several
minutes to respond and the dynamic changes can
be monitored by hand. Typical examples of
temperature-time graphs are shown in Fig. 4 for
both rising and falling temperature. The recycle
rate was 5 litres/min and the inlet flow rates 1.0,
1.5, 2.0, 2.5, and 3.0 litres/min.
A heat balance on the system for a small time
interval, dt, in which the outlet temperature, T,
changes by dT gives

QCTo + H = QCT + VC (dT/dt) (3)

where V is the volume of the recycle circuit which,
as an approximation, is assumed to be perfectly
mixed. Using Eq (1) to eliminate H, and then
integrating from To at time 0, gives

In [(T1 T) / (T To)] = -Qt/V (4)
T thus rises exponentially to the steady-state
temperature T, when the heater is switched on


time sees
FIGURE 4(a)


RECYCLE RATE = 5 I/min
Heater switched off ot time = 0


3 I/min -2.51 /min


200 300
time, t scs
FIGURE 4(b)


400 500 600


Figure 4. Results from the unsteady-state operation of the apparatus.
The recycle rate was fixed at 5 litres/min and the response is only
slightly dependent upon it. Fig. 4(a) shows the effect of switching the
heater on at different through flow rates. Fig. 4(b) shows the effect
of switching the heater off at different flow rates. The temperature
rises in Fig. 4(a) and falls in Fig. 4(b) exponentially to the limiting
temperature. The different limiting temperatures in Fig. 4(b) are
caused by the heat input from the recirculating pump and also by
small changes in the feed water temperature. Note that the re-
sponse time is a function of the inlet flow rate.


and falls exponentially to the temperature To
when the heater is switched off. The time constant
is independent of the heater power and also of
the recycle rate but depends on Q, the inlet flow
rate, and the volume of the system. By plotting
the log arithmetic term of Eq. (4) against time,
the gradient (-Q/V) can be determined. If this
is repeated for several flows then a graph of these
gradients against Q gives a straight line of slope
1/V through the origin.
The volume of the recycle circuit so deter-
mined is only an effective volume rather than a


CHEMICAL ENGINEERING EDUCATION























FIGURE 5. Logarithmic plots of the results of Fig. 4(a).


-0.3
in
f T,-
t
-0.6-

minri


0, litres/min
I 2 3

Heating *
Cooling






Gradient= I/V = 0240

V = 4.17 litres equivalent


FIGURE 6. The effective volume of the recycle system determined
from the gradients of the lines in Fig. 5 by plotting the gradient
against the through flow rate. Values from the curves of Fig. 4(b) are
also shown although the straight line logarithmic plots have not been
reproduced.



true internal volume because the metalwork of
the system behaves as a heat sink. Its effect is
quite large because the pump weighs several
pounds but conduction is fast enough for the
metal and fluid in the recycle loop to have the
same temperature. The temperature profiles of
Fig. 4 demonstrate that, as predicted by Eq. (4),
the system reaches equilibrium faster for higher
inlet flow rates than it does for lower inlet flow
rates.
Figure 5 shows the straight lines given by Eq.
(4) for rising temperature using the typical data
given in Fig. 4. Note that there is a delay of be-
tween 10 and twenty seconds before the ther-
mometer responds to the heater being switched
on, due to the transit time of the water in the
pipes. Fig. 6 shows the gradients of the lines of
Fig. 5 plotted against Q, the inlet flow rate, and
it is from the gradient of Fig. 6 that the effective
volume, V, of the recycle loop can be determined.


S2-




4'
0)

a.
E
aD
I-


Gradient = 3.00 degree-litres/min
3.00
Heat input 3 x 4.2 0.21 kW
60
















0
0/ ._0


I I/Q min/litre

FIGURE 7. The temperature rise of water passing through the system
obtained from the limiting temperatures of the cooling curves. (Fig.
4(b)) and the feed temperature plotted against the reciprocal of the
through flow rate. This graph is equivalent to the steady state results
of Fig. 3 but with the only heat input coming from the energy of
the pump. The slight offset of the line from the origin is most likely
caused by a systematic error between the two separate thermometers
which were used to measure the temperature rise.


REFINEMENTS

The analysis of the behaviour of this appara-
tus is straightforward. The accurate interpreta-
tion of actual experimental results is not so simple
because of drift in the temperature of the water
feed and other small effects. Rough and ready
results and analysis may be adequate for routine
teaching, but to get the best from the apparatus
a more refined approach is necessary. For example
it is better to extrapolate the dynamic experi-
mental data to obtain the steady-state tempera-
tures. This gives students useful practice in analys-
ing an exponential rise to a limit as well as giving
the steady-state temperatures more accurately.
The falling temperature curves give limiting
temperatures which, because of the heat input
from the recycle pump, are not equal to the inlet
water temperature To. Indeed the temperature
rise between the inlet water temperature and the
extrapolated outlet water temperature with the
heater switched off can be used in a heat balance
to determine the energy input by the pump. Fig.
7 shows AT, the temperature rise of water through
Continued on page 143.


SUMMER 1985










class and home problems

The object of this column is to enhance our readers' collection of interesting and novel problems in
Chemical Engineering. Problems of the type that can be used to motivate the student by presenting a
particular principle in class or in a new light or that can be assigned as a novel home problem are re-
quested as well as those that are more traditional in nature that elucidate difficult concepts. Please sub-
mit them to Professor H. Scott Fogler, ChE Department, University of Michigan, Ann Arbor, MI 48109.




ONE MONTH PROBLEM...

An Exercise in Modelling


V. RAVICHANDRAN
Indian Institute of Technology
Kanpur-208016, India

IN APPLIED MATHEMATICS courses the emphasis
is usually on solving equations. There is very
limited discussion about problem-definition and
expressing it in terms of mathematically under-
stood phenomena. A mathematically understood
phenomenon is one which, at least in its simplest
form, can be expressed mathematically [1]. Once
the problem is interpreted, it requires only the
substitution of symbols for words before a rele-
vant equation is obtained. Teaching this missing
part of the story is difficult because it is a crea-
tive process. There are no set procedures avail-
able for such an exercise. The students can, at


V. Ravichandran is an assistant professor at the Indian Institute
of Technology, Kanpur, India. Prior to coming to Kanpur he was a
visiting assistant professor at the University of Notre Dame where
he obtained his PhD (1981). He received his BTech in ChE from the
University of Madras (1977) and MS from Oklahoma State University
(1978). His research interests include a variety of topics including
chemistry of catalysis, biochemical engineering, mathematical
modelling, and application of microprocessor to chemical engineering.


best, be helped to learn by themselves. With this
in view, in a course entitled "Applied Mathematics
in Chemical Engineering," the students are
given a 'one month problem.' The problem is a
real life situation which has to be defined in such
a way that it can be expressed and analyzed
mathematically.
The students are encouraged not to get into
complicated mathematical formulations. This
strategy helps the students to concentrate and to
appreciate the subtle nuances involved in prob-
lem definition and modelling strategies. Thus the
scope of the 'one month problem' is limited and
should not be confused with the regular modelling
exercises. Wherever possible, the simple model
obtained is evaluated against the existing data.
Near the end of the semester the problems are
assigned to the students (one each) as a project,
to solve as regular modelling problems. One such
problem is discussed below.

PROBLEM
You are going to spend the winter in the
middle of nowhere, say in the Himalayas or in
Alaska, where the temperature gets very cold.
You are going to stay in a cabin where there is
no heating. How will you decide whether the
sleeping bag you have will keep you warm enough
or comfortable?

Solution
The best way to find out is to ask somebody
who has experienced the same climate. In the ab-
sence of an experienced person, however, we have
Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION









to resort to mathematical modelling to determine
how much insulation is necessary to keep the
body warm and comfortable. Before we proceed
with the solution, the term "comfort" has to be
defined in the context of the problem.
"Comfort" depends largely on the skin
temperature. When the skin temperature is high,
sweating begins and the latent heat of evaporation
cools the body down. It is very uncomfortable
when one starts sweating inside the sleeping bag.
Hence the temperature at which sweating begins
marks the upper limit of the "comfortable" skin
temperature, which is 34.5C [2].
The skin temperature begins to fall when the
skin is exposed to cold temperature. The self-de-
fense mechanisms of the human body try to main-
tain the skin temperature; however the com-
pensatory measures fail below 32 C, which is
known as the shivering temperature [2].
As long as the skin temperature is between
the sweating temperature and the shivering
temperature the person feels comfortable, i.e.,

Tw > Ts > Tsh

where T,, = the sweating temperature
T. = the skin temperature
Tsh = the shivering temperature.

From the above discussion the problem can
be redefined as follows: At a given outside
temperature, calculate the insulation necessary to
maintain the body temperature between shivering
and sweating temperatures.
The following assumptions are necessary to
make the problem mathematically tractable

The heat production rate is at q kcal/m2.hr and the
skin temperature is uniform throughout.
The loss of heat by convection, radiation, and
evaporation is negligible, and the heat is lost only
by conduction.
The air pocket between the sleeping bag and the
body is neglected.

Let us assume the body is rectangular in cross


Insulation



Body
Ts


FIGURE 1


section, and a sleeping bag of thickness t is cover-
ing it uniformly as shown in Fig. 1 (a). Since the
skin temperature is uniform throughout, a simple
one-dimensional model is sufficient to describe the
system, as shown in Fig. l(b). Under steady
state conditions the rate at which heat is pro-


4


E
S3

C
-2
o
O
0 2


-30 -20 -10 0 10 20
Surrounding temperature To, C
FIGURE 2


duced should equal the rate of
through the sleeping bag. Thus


heat conducted


dT
q = KA dx
dx-

and the integrated form is

t Kp(T,-T) K Ta + (KT) (1)
q q q


where A
T,
t
Kp


= 1
= surrounding temperature
= thickness of the sleeping bag
= thermal conductivity of the
packing material


For a given outside temperature and the
thermal conductivity of the insulator, the re-
quired thickness of the sleeping bag can be com-
puted using Eq. (1).
Fig. 2 shows the relationship between the sur-
rounding temperature and the bag thickness for
a man whose average basal metabolic rate is 40
kcal/m2 hr [2]. In the absence of any other in-
formation, the thermal conductivity of the bag
is assumed to be the same as that of animal wool,
i.e. 0.0315 kcal/m-hr-C [3]. It is very obvious
that this model fails closer to the ambient tempera-


SUMMER 1985









TABLE 1
Average basal metabolic rate for males and females
of various ages [2]


AGE


MALE


Kcal/hr.m2
FEMALE
43.0
35.0
35.0
35.0
34.0


ture because of 'no air pocket' assumption.
It can be easily shown that the required thick-
ness does not change with various age groups as
the heat production rate is not significantly differ-
ent (Table 1). In cases where the ground tempera-
ture is cooler than the atmospheric temperature,
we can make a conservative estimate of the bag
thickness by taking both the ground temperature
itself as the surrounding temperature and the
thermal conductivity of the compressed packing
material.
It was found that the assumption of cylindri-
cal shape for the body does not alter the result
significantly. O

ACKNOWLEDGMENT
Contributions of Umesh K. Jayaswal, Atul
Bansal, and V. L. N. Murthy are gratefully
acknowledged.

REFERENCES
1. Ravichandran, V., "Chemically Processed Mathe-
matics," to be published.
2. Bell, George H., J. N. Davidson and D. E. Smith,
Textbook of Physiology and Biochemistry, 8th Ed.,
1972.
3. Foust, A., L. A. Wenzel, C. W. Clump, L. Maus, and
L. B. Anderson, Principles of Unit Operations, 2nd
Ed., 1980.

INFORMATION TRAINING
Continued from page 131.
and Documentation in existence for a number of
years, with the objective of assisting the intro-
duction of new methods into the chemical engi-
neering profession. As part of this work they have
developed a suggested curriculum for a course in
information and documentation for chemical
engineers. This is given as Table 1. This table
could be taken as the basis for any new course de-
veloped for chemical engineers.
CONCLUSIONS
The aim of this paper has not been to give a


quick course on information and documentation,
but simply to mention the trends in this quickly
moving area and to indicate that there is sufficient
material relevant to a chemical engineer to form
a short course on the subject. If the reader is left
confused, but impressed, then we have achieved
our aim and suggest he get together with his own
information scientist (librarian) to develop a
course for his undergraduates.
We believe a course of about nine to twelve
hours would be ideal. This would enable about
three hours of exercises in the library to be made
and a computer retrieval demonstration to be at-
tended. If this amount of time is not available,
then two hours of lectures could survey the
material and practical experience could be gained

TABLE 1
Proposed Curriculum for Basic Information
Science Training
SOURCES OF INFORMATION
Printed
a) Primary Sources: Journals and reports, con-
ference reprints, patents, dissertations.
b) Secondary Sources: Chemical, Chemical Engi-
neering and Engineering Abstracts; SCI.
c) Tertiary Sources: Handbooks, encyclopedia,
books. Advances in List important
ones.
Computer Data Bases
a) Bibliographic data bases.
b) Numerical data banks.
SEARCH PROCEDURES
a) Manual: Indexing, Search Techniques; Biblio-
graphic, Data.
b) Computer Searching:
Bibliographic: files, networks, host computer; data
base selection; searching techniques; costs
Numeric Data Banks: available banks; procedure,
cost
c) The role of libraries and information scientists

in association with laboratory work and project
work. At least, practical experience should be
planned and guided-not simply left as a random
search for the student to undertake when all else
has failed. O

ACKNOWLEDGMENTS
The authors wish to express their thanks to
those members of the E.F.C.E. Working Party
on Information and Documentation who comment-
ed on the draft outlines of this paper. Their com-
ments were gratefully received and incorporated


CHEMICAL ENGINEERING EDUCATION










into the final text.

REFERENCES
Baltatu, M. E., "On-Line Information," Chem. Eng. (NY),
p. 69 (1984).
Fidel, R., D. SSrgel, "Factors Affecting On-Line Biblio-
graphic Retrieval: A Conceptual Framework for Re-
search," J. Am. Soc. Inform. Sci. 34 (3), pp. 163-180
(1983).
Fries, J. R., "Data Base Searching in Chemical Engi-
neering," Chem. Eng. (NY) 88 (26) p. 71 (1981).
Graham, M. H., A. B. Lamy, B. Lawrence, and L. Y.
Stroumtsos, "Information Retrieval," in Kirk-Othmer,
3rd. ed., 13, pp. 278-336, (1981).
Hall, J. L., M. J. Brown, "On-Line Bibliographic Data
Bases." An International Directory, 2nd. ed., Aslib,
London (1981).
Henry, W. M., J. A. Leigh, L. A. Tedd, and P. W. Williams,
On-Line Searching: An Introduction, Butterworths,
London (1980).
Kaback, S. M., "On-Line Patent Searching: The Realities,"
Online 7 (4), pp. 22-31 (1983).
Rasmussen, P., "Data Banks for Chemical Engineers,"
Danmarks Tekniske Hojskole, Lyngby, Denmark
(1980).
Rose, L. M., "Uebersicht iiber die gegenwiirtig ver-
fiigbaren Datenbanken fir physikalische Eigen-
schaften," CHIMIA 33, p. 256 (1979).
Stanley, W. G., "Unique Information Resources for the
Chemical Engineer," Chem. Eng. Prog. 77 (6), pp. 80-
82 (1981).


RECYCLE WITH HEATING
Continued from page 139.

the apparatus, plotted against 1/Q. The energy in-
put of the pump is found from the gradient to be
about 210 watts. The intercept (about 0.3C)
probably represents the scale reading difference
between the two thermometers.
A further refinement that is possible with the
apparatus is to run the dynamic experiment in the
limiting case of recycle with no through-flow.
With no through-flow the apparatus is analogous
to a well-mixed batch reactor, whereas it is an-
alogous to a CSTR when through-flow is present.
Fig. 8 shows results for this case for three differ-
ent recycle rates. The three lines do not coincide
because different starting temperatures were used.
The results show that after 30 seconds or so
there is, as expected, a linear temperature rise
with time. The temperature rises with no limit
at least until the safety cut-out of the shower
heater operates. The gradients of the lines on Fig.
8 are all the same and by using the combined
heater and pump energy input of 3.21 kW it is
possible to estimate the effective recycle volume.


This is 3.95 litres for the results shown, about 5%
less than the value obtained using the through-
flow method. The most likely cause is the time
taken to heat up parts of the metalwork of the
pump; this experiment lasts only four minutes,
compared to ten for the through-flow method.
Students always say that the apparatus could
be improved by lagging the pipework to reduce
heat losses, but simple measurements on a cool-
ing curve indicate that the heat losses are very
small. Also, for some of the temperature response


80-

70-

60-
-
50-

w40-
0
a.
E
1 20-

10-


Recycle Rate
* 3 litres/min
* 5 litres/min
S7 litres/min


Gradients = 0.193 "C/sec

If energy input is 3.21 kW then
3.21
the effective volume is 3.21
4.2 x 0.193


= 3.95 litres


U-
0 100 200 300
Time sees

FIGURE 8. With no through flow the recycle loop temperature rises
without limit as can be seen above. Using the combined energy input
of the heater and pump (determined on Fig. 3) the effective volume of
the recycle loop can be determined using the gradient of the lines.
This volume can be compared with the value determined on Fig. 6
(4.17 litres equivalent). The lines are for different recycle rates which,
as expected, have no effect. Different initial temperatures were used.
Up to the first minute it can be seen that the system is not well.mixed.

curves the water temperature is below the am-
bient air temperature and so the system is gain-
ing heat rather than losing it.

CONCLUSION

Our apparatus has been in service for several
years without giving trouble, perhaps a conse-
quence of using well proven domestic components.
The recycle experiments performed with it can
range from simple mass and heat balances right
through to the dynamics. Its main purpose, how-
ever, is to provide a vivid demonstration of basic
mass and heat balances in a system with re-
cycle. E


SUMMER 1985












IMPACT OF PACKAGED SOFTWARE


FOR PROCESS CONTROL ON


CHEMICAL ENGINEERING EDUCATION & RESEARCH


BRIAN BUXTON
Teesside Polytechnic
Middlesbrough, United Kingdom

IN AUGUST 1982 THE Department of Chemical
Engineering, Teesside Polytechnic, UK, took
delivery of a Ferranti Argus 700GL process
control computer system. The system was supplied
in accordance with a detailed enquiry specification
which defined precisely the objectives and scope
of the system (Table 1). The objectives of the
system are
To assist departmental research into varied chemi-
cal engineering topics by providing a compre-
hensive and flexible data logging and plant control
system
To provide a teaching facility for the department


The availability of packaged software
transforms this situation, enabling the engineer
(student or practitioner) to produce useful
process control software in a matter
of days rather than months.


by live demonstrations of plant monitoring and
control applications, simulation, and implementation
by students of control strategies.

It is now timely to report on the extent to
which these objectives have been realized. At the
time this paper is being written, the system is
capable of controlling two pilot plants and has
also been substantially integrated into our teach-
ing programmes. Computer control is now taught


TABLE 1
Enquiry Specification


1. Objectives and scope of the system
2. Extent of supply
3. Exclusions from supply
4. Functional specification
Data acquisition
Data logging
Pilot plant control
Operator interface
Data links
Development facilities
Teaching facilities
5. System hardware configuration
Configuration
Equipment specification
Control system description
Maintenance facilities
Availability/reliability
6. Supply of software
Standard systems software
Standard packaged application software
Special to project software for a) plant control
b) data links
High level language
Operator facilities


Management/engineer facilities
Failure/recovery
Expansion capability
7. General electrical & electronic design requirements
Equipment housing
Power supplies
Cable schedules
Environmental requirements
Safety requirements
Expansion capability
8. Acceptance tests
System hardware/software
Packaged software
Application software
System robustness
System loading
9. Installation and commissioning requirements
10. Documentation
11. Project time schedule
12. Maintenance and training requirements
13. Project management
Project organisation
Project communications and control
14. Commercial requirements


Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION













X C_7
,,., MU.I
ii raRE Lourro arxr
irsrr~ COI~OLE
m rlror PWKISI


DRIVES

(>!
\ ?
AINT INPUT/o0Tr
1OU-P-NT


Brian Buxton is a senior lecturer in the Department of Chemical
Engineering, Teesside Polytechnic, UK. He studied at the University
of Aston in Birmingham, receiving his BSc degree in 1967 and
his PhD in 1971. He spent 10 years in industry with both ICI and
the British Steel Corporation. During this period, he was responsible
for the specification, installation and commissioning of several com-
puter control systems. He joined Teesside Polytechnic in 1981 and
was responsible for the specification and procurement of the Ferranti
Argus computer control system featured in this article. His research
interests include the implementation of adaptive control techniques
on chemical processes.

in all the higher education courses offered by the
department
Higher Diploma
BEng Honours Degree Courses
Post Graduate Degree Courses (MSc and PhD)

as well as providing a key facility for our post-
graduate research teams.
It is emphasized that all the teaching pro-
grammes involve a substantial proportion of
practical experience on the computer system
coupled with live demonstrations of on-line com-
puter control. It has been found that this new
approach to teaching process control stimulates
considerable interest from the students who are
readily able to relate to these practical situations.
Furthermore, the experience gained on such


FIGURE 1. Computer System Configuration.


systems is much more directly applicable to the
industrial environment than the classical control
theory or the modern control theory commonly
taught in higher education courses.
The configuration of the computer system is
illustrated in Fig. 1 and defined in Table 2.
Sufficient industrial interface equipment has been
purchased to enable the system to control several
pilot plants simultaneously. It also provides con-
nection to simulation equipment.
The simulation equipment facilitates both teach-
ing and testing of research software. The mono-
chrome VDU's may be sited alongside pilot plants
to provide local operator display and control facili-
ties. Software development may also take place
at these locations if required. Further colour
graphics terminals will be added to the configura-
tion in the future.
The pilot plants are accommodated in three
module rooms. These rooms extend from the
ground to the top floor of the building and can ac-


TABLE 2
Computer System Configuration


EQUIPMENT

Argus 700 GL processor
Semiconductor stores (256 Kb)
Monitor and control console


QUANTITY
1
2


Peripherals
Monochrome VDU's (15 inch display
heads and keyboards)
20 inch colour monitor and functional
keyboard
Matrix printers (180 cps)
Keyboard for printer
Plus drive cards for all peripheral de-
vices and serial input/output cards


for data links
Storage Media
Twin cartridge disc storage system
(10 Mb) (one exchangeable, one fixed)
Twin floppy disc storage system
(1.0 Mb)
Industrial Interface Equipment
Analogue inputs
Analogue outputs
Digital inputs
Digital outputs
Pulsed digital outputs
Plus usual power supplies, fans, pack-
aging, etc.


SUMMER 1985


/



/


- --TXoN ..NE


\-








commodate large column type processes. A pair
of reactor bays is also provided on each floor of
the building. Multicore cables have been laid to
link the computer to pilot plants in all of the above
locations.

CONTROL PACKAGES
The standard system software P.M.S. (Pro-
cess Management System) encompasses all the
facilities required to implement, operate, and
manage a computer controlled process. Software
packages have been provided by the computer
manufacturer which greatly assist the engineer
in building the application software required to
operate his particular plant. It is this facility
which enables the teaching of the subject within
the time scale and context of a higher education
course.
Prior to the availability of control packages,
the general approach of computer system suppli-
ers was to provide "tailor made" software for a
specific application in the form of a so-called
"turn key" contract. The software was written in


Ferranti computer control system.


a real-time high level language such as CORAL.
This meant that engineers were either required to
learn in depth a high level language and the as-
sociated operating system of the host computer
system, or to define their system requirements to
a programmer, who in turn implemented the re-
quired functions in software. Either of these op-
tions was time consuming, costly, and therefore
inefficient. The time scale required to learn such
programming skills can be measured in months,
rather than weeks, of dedicated work, which makes
it impossible for it to be incorporated as part of a
higher education course.


The task of the engineer is then
to select which operations are needed for
a specific case and to link them
together accordingly.


The availability of packaged software trans-
forms this situation, enabling the engineer
(student or practitioner) to produce useful pro-
cess control software in a matter of days rather
than months.
Specifically, the packages assist the engineer
in implementing the following functions in soft-
ware
Interfacing of plant signals to and from the com-
puter
Continuous control
Sequence control
Operator interface: a means of display and modi-
fication of process and control information.

All are clearly essential for the commission-
ing of any computer control system. The packages
are based on the principle that certain operations
are common to all process control applications,
while the order in which they are applied is spe-
cific to the particular application in question.
The task of the engineer is then to select
which operations are needed for a specific case
and to link them together accordingly. The pack-
age provides considerable assistance with this
linking "construction" by providing a conversa-
tional facility for the engineer in the form of
displayed messages (prompts). The task is then
reduced from one of detailed programming to
one of deciding on a control strategy and then de-
fining a series of operations and associated
parameters to implement the strategy. Thus, vir-
tually no programming skills are required and the
problem of programming errors which normally
arise in the programming of complex software is
largely avoided.

TEACHING PROGRAMS
In the context of control packages, the teach-
ing of control system design, from initial strategy
to implementation and testing of software using
hardware and software simulators, is entirely
practicable.
Every opportunity has been taken to incorpor-
ate our computer control facilities in our teaching
programmes. These include
Laboratory Practicals for the Higher Diploma


CHEMICAL ENGINEERING EDUCATION









students: e.g., interfacing of plant measurements.
This requires that the student generate the software
to condition and convert electrical signals into
engineering units. The operation of the software is
then tested by means of simulation panels.
*Short Course (10h) for the final year of the BEng
course. The course includes several practical sessions
on building software to interface signals, continu-
ous control loops, and operator displays. The pro-
ject used to assess the students in the current
academic year requires that the students work as
a project team to generate the entire software to
monitor, data log, and control a fermenter. The
facilities will include sequence control of the plant
and a colour graphic display of the process pro-
viding a live mimic of the plant operation. This is
no artificial project since the software produced by
the undergraduates will ultimately be used by the
department's biotechnology research team to imple-
ment computer control on a newly acquired fer-
menter.
Mention should also be made of the allocation
of a limited number of research projects to second-
year degree students which involve the computer
control of laboratory scale apparatus. Current
projects involve the control of pH and level.
Chemical engineering also offers service teach-
ing to other Polytechnic departments. The op-
portunity has, therefore, been taken to offer com-
puter control of a pilot plant as a case study.
This academic year, students from both the Com-
puter Science Department (Information Tech-
nology MSc Course) and the Department of
Electrical, Instrumentation and Control (BSc2),
have received a concentrated study on computer
control of a specific pilot plant. Like the other
courses offered, the courses include a substantial
proportion of practical experience on the com-
puter system and live computer control demon-
strations.

POST GRADUATE RESEARCH
With regard to research, the main thrust has
been directed toward the commissioning of direct
digital control of a gas absorption column. This
work involved the use of adaptive control (the
self tuning regulator) which has been used to
optimise the operation of a cascade loop on the
column. This research is reported in a separate
paper [1] and will not be considered further here.
However, it is worth noting that the speed with
which this research was implemented owes a great
deal to the availability of packaged software on
the system. While the self tuning regulators were
in fact programmed in a high level language, the
interfacing of this software with the control


packages (which are responsible for all other
control facilities) was straightforward and
rapidly achieved. It should be noted that apart
from this one specialized application, all our soft-
ware requirements to date have been easily imple-
mented by the control packages.
Future research effort will be directed to the


Graphics display of gas absorption column pilot plant.

implementation of computer control on a novel
catalytic reactor which has been developed within
the department over a number of years [2]. The
control system will facilitate prolonged operation-
al runs and assist in further research into com-
mercial application and scale up of this unique
reactor. The plan is to apply the adaptive control
techniques (recently proven on the gas absorption
column) to this reactor. This process lends itself
particularly well to these techniques in view of
its time varying nature due to the decaying
catalyst. This is the main target for the research
team.
In conclusion, it is clearly important to recog-
nise the potential of packaged software in the
teaching and research environment. (There are
also considerable implications for the industrial
applications, but that is beyond the scope of this
paper.) Packages are rapidly gaining recognition
as vital tools for the modern chemical engineer.
In an environment of continuously falling com-
puter hardware costs, coupled with the ever-rising
costs of producing "tailor made" software, it is
essential that the engineer makes full use of com-
mercially available packages. The cost of plant de-
sign, implementation and operation of chemical
processes and their associated automation systems
can be considerably reduced by judicious use of
Continued on page 161.


SUMMER 1985










S classroom


ESTIMATION OF


FLUID PROPERTIES AND PHASE EQUILIBRIA
M. HERSKOWITZ
Ben-Gurion University of the Negev
Beer-Sheva, Israel


N UMERICAL VALUES OF physical, thermodynamic,
and transport properties of pure compounds
and mixtures are necessary for the development
of chemical processes and the design of chemical
plants. Experimental data available in the litera-
ture are limited but the need for the estimation of
such properties is crucial in calculations carried
out by chemical engineers. The study of correla-
tions for estimating various properties is an inte-
gral part of courses in transport phenomena and
thermodynamics.
Considering the importance of the subject, a
course designed to cover the theoretical and practi-
cal aspects of properties estimation was intro-
duced into the curriculum. The course is given to
junior and senior students who have a strong back-
ground in thermodynamics and transport phe-
nomena.
Throughout the course, two fundamental
methods for estimating properties are emphasized
Corresponding states principle (CSP)
Equations of state (EOS)
Another method is the group contribution
method. This approach is used for estimating
thermodynamic properties of ideal gases (no
intermolecular forces) and also for estimating
critical points of pure compounds [1] and activity
coefficients in the liquid phase [7].
The outline of the course is listed in Table 1.
Since this field is very dynamic, the outline is up-
dated every year according to new developments.
All correlations and samples of calculation are
organized in a manual distributed to the students.
During the lectures the theoretical basis of the
correlations is discussed and the advantages and
disadvantages of various correlations are pointed
out.
In the first lecture the students receive a list
of primary, secondary, and tertiary literature
sources which are useful during the course. The


M. Herskowitz completed his PhD in chemical engineering at the
University of California, Davis, in 1978, and since 1979 has been a
faculty member at the Ben-Gurion University of the Negev, Beer-
Sheva, Israel. His principal interests are multiphase reactor design,
synthetic fuels, and estimation of thermodynamic properties. In
1984-85 he is spending a sabbatical with Exxon Research and Engi-
neering Co. and at the University of Delaware as a visiting professor.

book of Reid et al [1] is recommended as an excel-
lent reference to correlations published until 1976.
Other books [2, 3, 4] are used as references to the
theoretical basis in properties estimation. The
proceedings of the International Conference on
Phase Equilibria and Fluid Properties [5, 6] are
also valuable references. The students are en-
couraged to read original papers in order to gain
some insight into the limitations of the various
correlations.
The material studied during the course is
practiced in homework problems which include ap-
plications of the correlations. For this purpose
computer programs are available in topics such as
Phase equilibria calculations by the UNIFAC
method
Phase equilibria calculations by EOS
Calculation of critical points of mixtures
Some of the programs were provided by Ras-
mussen [8].
The students are also required to work on a
project. Each student selects a certain property
and prepares a report which includes
A literature search that covers a period of the last
three years, based mainly on Chemical Abstracts


CHEMICAL ENGINEERING EDUCATION


Copyright ChE Division, ASEE, 1985










but also on current journals.
Selection of two papers dealing with general cor-
relations, a summary of the basic approach, and the
conclusions.
Selection of a limited database from the literature
for testing the correlations. Only primary sources
are used with proper estimation of the experimental
accuracy of the data.
A comparison of the correlations and practical con-
clusions.

Working on this project, the students gain ex-
perience in the literature search, the understand-
ing of correlations, and their proper applications.

TABLE 1
Course Outline*

INTRODUCTION: 5 Lectures**
a. Corresponding states principle (CSP): theoretical
background [2, 9]
b. Classification of fluids: simple, normal, polar and
quantum [9]
c. Critical points of pure compounds: Lydersen [1],
Ambrose [10]
d. Equations of state (EOS) [11]: cubic EOS, the
virial EOS, mixing rules
e. Critical and pseudocritical properties of mixtures,
mixing rules

PHYSICAL AND THERMODYNAMICAL PROPERTIES:
18 Lectures
a. Molar volume of gases and liquids
1) CSP: Lee-Kesler [12], Teja et al [13]; COS-
TALD [14], Gunn-Yamada [1] for liquids
2) EOS: Redlich-Kwong [1], Soave-Redlich-Kwong
[1], Peng-Robinson [15]
3) Virial EOS: Tsonopoulus [1], Hayden-O'Connell
[16], Orbey-Vera [19]
b. Enthalpy, entropy, fugacity, and heat capacity
1) CSP: Lee-Kesler [12], Tyagi [20]
2) EOS: RK [1], SRK [1], PR [15]
3) Construction of diagrams such as the Mollier
diagram
c. Vapor pressure and heat of vaporization: Lee-Kesler
[12], Riedel [1], Vetere [17]
d. Thermodynamic properties of ideal gases: Thinh-
Trong [18] for hydrocarbon, Benson [1]
PHASE EQUILIBRIA-VLE, LLE, SLE, GAS-
SOLUBILITY: 9 Lectures
a. Theoretical background [2, 3]
b. EOS [3]: SRK [1], PR [15]
c. Group Contribution Methods: UNIFAC method [7]
TRANSPORT PROPERTIES: 10 Lectures
a. Theoretical background [4]
b. Viscosity: Reichenberg [1], Ely-Hanley [21]
c. Thermal conductivity: Ely-Hanley [22], Euken [1],
Roy-Thodos [1], Robbins-Kingrea [1]
d. Diffusion coefficients: Wilke-Chang [1], Scheibel [1]

*Only part of the references are listed.
**Each lecture lasts 50 minutes.


This is also an opportunity to test the reliability
of experimental data. Some projects have yielded
interesting results which stimulated further re-
search.
The course is a good opportunity to review and
emphasize the practical aspects of fundamental
principles in thermodynamics and transport phe-
nomena. Five classes of students have already com-
pleted this course. They found it useful in practical
courses such as plants design, unit operations lab,
and the senior project. Furthermore, it provides
some of the tools a practicing chemical engineer
needs. O

REFERENCES
1. Reid, R. C., J. M. Prausnitz and T. K. Sherwood, The
Properties of Gases and Liquids, McGraw Hill, 3rd
Ed., N.Y. (1977).
2. Prausnitz, J. M., Molecular Thermodynamics of Fluid-
Phase Equilibria, Prentice-Hall, Englewood Cliffs,
N.J. (1969)
3. Van Ness, H. C. and M. M. Abbot, Classical Thermody-
namics of Nonelectrolyte Solutions, McGraw-Hill,
N.Y. (1982).
4. Hirschfelder, J. 0., C. F. Curtiss and R. B. Bird,
Molecular Theory of Gases and Liquids, J. Wiley, N.Y.
(1954).
5. Sandler, S. I. and T. S. Storvick, eds., "Phase Equilib-
ria and Fluid Properties in the Chemical Industry,"
ACS Symp. Ser. 60, Washington (1977).
6. Renon, H., ed., "Fluid Properties and Phase Equi-
libria for Chemical Process Design", Fluid Phase
Equilibria, 13, 14 (Special ed.) (1983).
7. Fredenslund, A., J. Gmehling and P. Rasmussen,
Vapor-Liquid Equilibria Using UNIFAC, Elsevier,
Amsterdam (1977).
8. Rasmussen, P., Private communication (June 1983).
9. Leland, T. W. and P. S. Chappelear, Ind. Eng. Chem.,
60 (7), 15 (1968).
10. Ambrose, D., NPL Reports 92 and 98, NPL, Tedding-
ton (1979).
11. Abbott, M. M., Adv. Chem. Ser. 182, 47 (1979).
12. Lee, B. I. and M. G. Kessler, AIChE J., 21, 510 (1975).
13. Teja, A. S., S. I. Sandler and N. C. Patel, Chem. Eng.
J. 21, 21 (1981).
14. Hankinson, R. W. and G. H. Thomson, AIChE J., 25,
653 (1979).
15. Peng, D. Y. and D. B. Robinson, Ind. Eng. Chem.
Fund., 15, 59 (1976).
16. Hayden, J. G. and J. P. O'Connell, Ind. Eng. Chem.
Proc. Des. Dev., 14, 209 (1975).
17. Vetere, A., Chem. Eng. J., 17, 157 (1979).
18. Thinh, T. P. and T. K. Trong, Can. J. Chem. Eng.,
54, 344 (1976).
19. Orbey, H. and J. H. Vera, AIChE J., 29, 107 (1983).
20. Tyagi, K. P., Ind. Eng. Chem. Proc. Des. Dev., 14,
484 (1975).
21. Ely, J. F. and H. J. M. Hanley, Ind. Eng. Chem. Fund.,
20, 323 (1981).
22. Ely, J. F. and H. J. M. Hanley, Ind. Eng. Chem.
Fund., 22, 90 (1983).


SUMMER 1985









S laboratory


AN INNOVATIVE CHE PROCESS LABORATORY


SKIP ROCHEFORT, STANLEY MIDDLEMAN
AND PAO C. CHAU
University of California, San Diego
La Jolla, CA 92093

T HE CHEMICAL ENGINEERING Program has re-
cently been introduced into the Department of
Applied Mechanics and Engineering Sciences
(AMES) at the University of California, San
Diego (UCSD). The first courses in chemical engi-
neering were offered in the fall of 1979. The
strategy was to integrate the new discipline into
the previously existing engineering curriculum
(fluid mechanics, thermodynamics, engineering
mathematics, etc.) while gradually introducing
traditional chemical engineering courses. A
genuine chemical engineering program was
achieved in the fall of 1982.
Initially targeted as one of the major priori-
ties was the establishment of a chemical engineer-
ing undergraduate unit operations laboratory to
be given at the senior level. We also determined
at an early stage that we should develop the in-
novative skills of the students and not follow the


typical cookbook recipe formats so prevalent in
many chemical engineering departments. During
the past four years, the laboratory has evolved as
a setting in which our seniors refine the classroom
skills they have acquired and attack problems
under circumstances similar to industrial ex-
perience. Under space, faculty, and financial re-
straints typical of many academic programs, we
have developed what we feel is a unique approach.
The Chemical Engineering Process Laboratory is
taught at the senior level over two quarters, and
has proven to be successful for a class size under
forty, with the involvement of two faculty mem-
bers and a teaching assistant.
PHILOSOPHY
Our main goal is to provide an environment in
which the students have a large degree of control
over the direction of their work. Students are
skilled at following instructions and obtaining
solutions to well-posed problems, situations which
are not likely to occur in industry. We would like
them to develop the ability to formulate a problem
in process analysis and design, design and perform


Skip Rochefort received his BS from the University of Massachusetts,
his MS from Northwestern University, and is currently working toward
his PhD at the University of California, San Diego. He also worked
at the AT&T Bell Research Labs after receiving his MS. (R)
Stanley Middleman earned his baccalaureate and doctoral degrees
at The Johns Hopkins University and was a professor of chemical engi-
neering at the University of Massachusetts before coming to the


-
University of California, San Diego. His major research interests are
in the areas of fluid dynamics, especially rheology and polymer pro-
cessing. (C)
Pao Chau is an assistant professor at the University of California,
San Diego. He received his BS from the University of Delaware and
his PhD from Princeton University. (L)


Copyright ChE Division, ASEE, 1985


CHEMICAL ENGINEERING EDUCATION









experiments to elucidate the problem, analyse the
data and present pertinent results in a concise
form, and draw conclusions in support of recom-
mendations of further action.


STRUCTURE


The structure of each lab group is similar to
that of an industrial process research and develop-
ment group, with a project head (faculty advisor),
group leader and group members, and technical
support staff. A fairly general problem statement
is presented by the project head and the students
are instructed to arrive at the "best solution" to
the problem given constraints in funds, equipment,
and time (ten weeks). An example of a typical
problem statement is shown in Fig. 1. (Blax/
Beech, Inc. is a pun on Black's Beach, a local nude
beach and prime surf spot.)
The students are expected to outline an experi-
mental approach to the problem, design and build
the necessary experimental apparatus, perform
appropriate experiments, and analyze the data.
The design and construction process includes se-
lection of material, pumps, valves, fittings, etc.,
and interaction with the technical support staff
who do most of the machining. The lab group also
has to select appropriate analytical and measuring
devices (e.g., gas chromatograph, viscometer, pH
meter, thermocouples, etc.), as well as proper data
acquisition procedures (e.g., IBM PC with A/D
card, multichannel DVM, strip chart recorder,
etc.). Once they have selected a device, the students
are expected to learn from instruction manuals
provided by the manufacturers, and to perform
all necessary calibrations. No exceptions are made
with the more expensive equipment such as gas
chromatographs, a Brookfield viscometer, or IBM
personal computers. The technical staff is avail-
able for consultation but only intervenes when
procedures undertaken by students may endanger
the equipment or themselves.
During the planning phase, the students are
encouraged to contact local industry for ideas, and
to consult equipment manufacturers and field
representatives when necessary. They are also
urged to examine and keep abreast of the current
research literature in their problem area over
the project duration. During the second quarter
of the laboratory, they are encouraged to apply
what they have learned in computer-aided design
and process design courses to the modeling and
design of their experiments.


During the past four years, the
laboratory has evolved as a setting in which
our seniors refine the classroom skills they have
acquired and attack problems under circumstances
similar to industrial experience.




Blax / Beech Inc.
Design Consultants to the Chemical Process Industries
La Jolla, California



Date: January 10, 1985
To: CVD Reactor Group
From: Stanley Middleman, Director
Re: Mass Transfer in a CVD Reactor
Chemical Vapor Deposition (CVD) is a heterogeneous reaction process by
which various chemical species may be deposited as very thin films on silicon
wafers. In the manufacture of semiconductor materials, CVD reactors provide a
means of contact of a gas mixture with a set of wafers. One problem in design of
such reactors lies in the fact that mass transfer may affect the deposition rate, and
that the rate of mass transfer may not be spatially uniform in a CVD reactor.
You are to design an experimental system with which you can explore factors
that affect the rate and degree of uniformity of mass transfer in a CVD reactor.
Beginning January 17, and each week thereafter, I expect to receive a typed
progress report. We shall also have a weekly meeting at which time your group
will make a twelve minute oral presentation to the class on progress and plans for
future work. A final presentation is to be given during the week of March 13 and
a final report is to be in my hands on March 19.
Please do not hesitate to contact me if you need any technical or administra-
tive help in facilitating your progress.
FIGURE 1. Problem statement to CVD lab group.


Strong emphasis is given to oral and written
communication skills. Each week the group meets
with the project head to discuss the project and
present a written progress report. Project goals
may be modified if justified by preliminary experi-
mental results or other extenuating circumstances.
The group also has to give weekly oral presenta-
tions to the entire class.


COURSE ORGANIZATION
Students work in groups of three or four. After
receiving their problem statement, they have two
weeks to research the problem area, check out the
available resources, consult with the project head,
specify the goal and postulate the strategy to solve
the problem. The project head mainly serves to
provide insights as to whether the proposed pro-
ject is feasible, trivial, or too ambitious for a ten-
week period.
The next four weeks are spent either in con-


SUMMER 1985








struction of new equipment or in modification of
an existing apparatus, in performing preliminary
experiments and in making further equipment
modifications as required. Students are required
to submit a mock purchase order for supplies and
a job order requesting the assistance of the techni-
cal staff in building equipment. To avoid time lag,
the lab has to stockpile common items such as
rotameters, glassware, valves and fittings. Pre-
liminary experiments usually entail equipment
calibration, determination of necessary thermo-
dynamic and physical properties data, solution
preparation, and at least several trial runs of the
experiment. The main purpose of these prelimin-
ary experiments is to allow the students to become
familiar and comfortable with the new equipment
and to develop clean and efficient techniques. In
the process they also learn the importance of care-



Chemical Process Laboratory
Oral Presentation Evaluation
Speaker:
Lab Group: Date:
Category Poor Good

1. Presence 1 2 3 4 5
(Posture, Voice,
Eye contact, Delivery)
2. Visual Aids 1 2 3 4 5
(Effectiveness, Clarity)
3. Length of Talk 1 2 3 4 5
4. Audience Contact 1 2 3 4 5
(Audience stimulation,
Response to questions)
5. General Organization 1 2 3 4 5
(Introduction, Body,
Summary, Clarity)
6. Technical Content 1 2 3 4 5
(Was any work done?
Data presentation and
analysis)
7. Overall Effectiveness 1 2 3 4 5
8. If you were this person's boss,
would you give him/her a raise?
Would you continue funding for the
project?
9. Comments:


FIGURE 2. Oral presentation evaluation form.


ful planning of experiments and the validity of
Murphy's Law in experimental research.
The remainder of the ten-week quarter is used
to perform final experiments, analyze data, and
prepare final oral and written reports.
During the course of the quarter, the groups
are required to submit a weekly progress report
(five to eight pages). The grading of the report is
broken down into technical content and style. Ex-
tremely strong emphasis is given to proper writing
style at the beginning of the first quarter. As the
writing improves, the grading emphasis moves
more toward technical content, much like a
refereed journal article might be critiqued. The
group leader, who rotates every week, has to edit
the report and do the rewriting if requested. Be-
cause report revisions are often requested, word
processing of the reports is encouraged, using the
CATT system on VAX or WordStar on the IBM
PC. Over two quarters and including the final re-
ports, each student should have participated in
writing sixteen reports.
For the weekly oral report, students are re-
quired to give a twelve- to fifteen-minute presenta-
tion in which the use of visual aids (either trans-
parencies or slides) is mandatory. The presenta-
tions are critiqued immediately after each session
by the instructor for the benefit of all. Evaluation
forms (Fig. 2) from classmates are passed on to
the speaker after the instructor has reviewed them.
Students sometimes find that the harshest com-
ments come from their peers.
We schedule two separate oral presentation
sections per week, each under the supervision of
one of the instructors assigned to the laboratory.
Lab groups are rotated in a staggered fashion
through these sessions over the quarter. Thus each
student faces a different audience for each talk.
Moreover, the entire class is exposed to all the
different experiments being conducted in the lab.


LIST OF EXPERIMENTAL PROJECTS

We have listed in Table 1 the experimental
projects that were carried out during the 1984-85
academic year (2 quarters; 20 weeks). The ob-
jectives listed are a synopsis of the general prob-
lem statement which was presented to each lab
group at the start of the project.
Several of these experiments are interrelated
and provide an opportunity for productive com-
munication between groups. The gas-lift reactor
experiment permits examination of gas-liquid


CHEMICAL ENGINEERING EDUCATION








mass transfer in a reactor uniquely designed for
the algae growth experiment. The effects of sparg-
er design, bubble size, gas flow rate, and solution
electrolyte content on oxygen mass transfer are
examined, with special attention given to their
role in algae growth.
The aerated stirred-tank experiment keys on
mixing and oxygen mass transfer problems in
microbial exopolysaccharide production, which is
of interest to a local company (Kelco). Through
pre-arrangement on the part of the instructors,
specific members of the technical staff of Kelco are
available to meet with students and provide con-
sultation.
In the gas absorption experiment, in-line static
mixers are used to study carbon dioxide absorp-
tion into a dilute sodium hydroxide solution in a
cocurrent pipe flow configuration, as might be
applied to an industrial "gas sweetening" pre-
treatment process. The system was donated by
Komax, which is interested in obtaining perform-
ance data for its Komax Mixers in this type of ap-
plication.
Engineers at Chevron Oil Field Research
(COFR) in nearby LaHabra first stimulated our


interest in the use of dilute polymer solutions in
enhanced oil recovery. Using information they pro-
vided, the students were able to set up an experi-
mental study of the effects of polymer configura-
tion in dilute solution on the removal of oil from
packed beds. Cylindrical and two-dimensional
planar beds with various bead and sand packing
have been used. Typical oil recovery polymers,
supplied by Kelco and Dow Chemical Co., have
been used in both pure water and brine solutions.
A variety of experiments have been conducted
over the past several years, ranging from single
"oil blob" movement in a bed with a monolayer
of uniform glass bead packing, to bulk oil dis-
placement from a cylindrical sand packed bed.
Parameters of interest are polymer concentration
necessary for oil displacement, polymer degrada-
tion and adsorption in the packed beds, and the
effect of salts on these results.
The chemical vapor deposition (CVD) experi-
ment required the design of a model of an in-
dustrial CVD reactor for the purpose of studying
mass transfer effects on the vapor deposition pro-
cess. The development of this experiment was
greatly influenced by contacts with researchers in


TABLE 1
Experimental Projects in 1983-84


PROJECT

1. Mass Transfer in CVD:
To study the role of mass transfer in chemical vapor
deposition processes.
2. Enhanced Oil Recovery/Porous Media Flow:
To study efficiency of polymers in enhanced oil re-
covery. To look into effects of theology, polymer
degradation and adsorption. Flow visualization of
oil "blob" movement in porous bed.
3. Mass Transfer in gas-lift Reactor:
The analysis of oxygen mass transfer in fermenta-
tion systems. Effect of electrolytes and fluid proper-
ties on bubble dynamics. Reactor and sparger design.
4. Aerated Stirred Tank Mixing:
The study of mixing and gas-liquid mass transfer
in an aerated stirred tank with non-Newtonian
fluids. The application of novel impeller geometries.
5. Gas Absorption:
To obtain design data for a cocurrent pipe flow gas
absorber using in-line static mixers.
6. Heterogeneous Catalytic Reactor:
Kinetics of heterogenous catalytic reactions. To
assess mass and heat transfer effects in catalytic
CO oxidation and methanation reactors.
7. High Fructose Syrup Production:
The study of immobilized enzyme kinetics, enzymatic
reactor design, and ion-exchange column operation
in the production of high fructose corn syrup,


8. Mixing in Chemical Reactors:
To study the effect of non-ideal mixing in the per-
formance of tubular and stirred-tank reactors.
9. Ethanol Fermentation:
Ethanol production in batch and continuous fer-
mentation. Fermentation kinetics and bioreactor de-
sign.
10. Algae Growth:
The use of algae in biomass production. Effect of
mass transport and bubble dynamics on the kinetics
of algae growth.
11. Hollow Fiber Membrane Separation:
To study the design problems of hollow fiber separa-
tion of biomass in application to microbial systems.
12. Distillation:
Batch and continuous azeotropic distillation prob-
lems with an isopropanol/water mixture.
13. Liquid-Liquid Extraction:
The mass transport phenomena and design of a
liquid-liquid extraction column with soybean oil as
the organic phase.
14. Plate Heat Exchanger:
To design, construct and operate a plate heat ex-
changer system for use with viscous gelatin solu-
tions.
15. Wetted Wall Column:
Study of gas-liquid mass transfer in falling films
of viscous fluids and in the presence of surface-
active agents.


SUMMER 1985








the local semiconductor industry who were drawn
to UCSD, in part, through the spring quarter
Chemical Engineering Seminar Series, which was
developed with the theme "Applications of Chemi-
cal Engineering in Semiconductor Technology."
An experimental system was built in which
naphthalene in a nitrogen carrier gas was de-
posited on the surface of an acrylic disc. The
elimination of chemical reaction from the process
served to isolate the mass transfer phenomena.
In the catalytic reactor set-up we have pro-
visions for either CO oxidation or methanation re-
actions in either packed-bed, recycle, or single-
pellet reactor configurations. All recording equip-
ment, including thermocouples and the gas chroma-
tograph, are interfaced to an IBM PC. A BET ap-
paratus is also available for surface area and
chemisorption experiments. The combination of
all these options allows for a variety of interesting
experiments for the students to plan and design.
A biochemical application of the principles of
kinetics and reactor design is investigated in the
high fructose corn syrup production experiment.
This experiment was implemented with the help
of information supplied by Staley Co., using im-
mobilized enzymes and ion-exchange resins donat-
ed by Novo and Dow Chemical Co., respectively.
The goal of the project is to look at more rational
reactor and process design procedures. Computer
modeling of the reaction/deactivation kinetics is
also included.
Classical chemical engineering kinetics and re-
actor design experiments are conducted by study-
ing mixing in stirred-tanks and tubular reactors.
Mixing, as well as mixing with chemical reaction,
has been studied in any number of reactor
geometries-batch, stirred-tanks in series, tubu-
lar flow with static mixers or packed-beds, and
any combination of these. Residence time distribu-
tions are studied with colored dye tracer and a
spectrophotometer with a flow-through cell.
Along with some of the previously mentioned
experiments which have a biochemical twist to
them, we have a series of experiments which are
more directly oriented towards biochemical engi-
neering. Ethanol production is carried out by fer-
mentation using both single and multiple substrate
growth media. The extensive cell growth, substrate
utilization, and ethanol production data are com-
pared to data generated using classical biochemi-
cal kinetic rate models in computer simulations.
The algae growth experiment was initiated
due to the interest of a group of scientists at


We also have a lab which allows our
students to get acquainted with new industrial
developments, such as microelectronic fabrication and
biotechnology, and with the integration of new
technology... into laboratory experiments.


Scripps Institute of Oceanography. They have
studied the optimum biological growth conditions
(i.e., pH, light, growth medium, and temperature),
while our engineering students concentrated their
efforts on the role of mass transport in algae
growth. As mentioned previously, we have de-
signed a two-dimensional, gas-lift reactor in which
both algae growth and mass transfer experiments
are conducted. The two-dimensional geometry is
useful for flow visualization experiments to deter-
mine bubble dynamics and mixing in the reactor.
The goal is the optimization of algae growth with
respect to mass transfer limitations, while keep-
ing biological parameters constant.
We have used hollow fiber modules donated by
Asahi Medical Co. to conduct simple membrane
separation experiments. The goal is to examine a
process technology for concentrating cell mass in
either cell recycle or biomass production processes.
We do have some conventional chemical engi-
neering unit operations experiments in the lab.
In the distillation experiment, the students have
had to design their own plumbing and control
schemes to convert a three inch diameter, six stage
batch bubble cap column to continuous operation.
The column feed is a cleaning solution provided by
the university glassblower (a 35/65% isopropanol/
water mixture with some minor impurities). Ex-
tractive distillation techniques (e.g. the addition
of a salt into the column) has been applied to pro-
duce an isopropanol/water distillate of 85-90%
purity. The students must also generate their own
thermodynamic data. A gas chromatograph is used
for data analysis and computer simulations of the
distillation column are also conducted.
The liquid-liquid extraction experiment uses
soybean oil as the organic phase, mainly due to
cost and safety reasons, but also because of the
novelty of the process. The operation of the column
for such a viscous continuous phase is quite differ-
ent from conventional extraction processes. The
students must design experiments to examine
transport phenomena in the column (e.g. droplet
coalescence and break-up) and they must deter-
mine solubility data before they can design and
conduct the extraction experiment.


CHEMICAL ENGINEERING EDUCATION







The plate heat exchanger experiment was initi-
ated and financed through a contract received from
Eastman Kodak Co. The interest of Kodak is in
the use of a plate heat exchanger to heat and cool
photographic gelatin solutions. The students must
design and construct the experimental apparatus
and then obtain the heat transfer and design data
required by Kodak. The experimental and logisti-
cal novelty of this project is that the process fluid
is a gelatin solution and the students act as if in
a consulting capacity to a contracting employer.
This program will continue over several quarters
and will require that students study the reports
of preceding groups, building upon their progress.
The wetted-wall column is a standard counter-
current gas/liquid contacting device. The students
are able to change tube dimensions and gas and
liquid Reynolds numbers to examine mass transfer
coefficients in different flow regimes. Water/air
mass transfer data are compared to classical cor-
relations. The use of the column with surface ac-
tive agents and to concentrate viscous aqueous
solutions has also been investigated.

DISCUSSION
Since our students only work on one project
each quarter (compared with the more standard
rotation of four to six experiments), it appears
that we are sacrificing breadth of exposure to
different processes for in-depth studies of two
topics. However, a single project quite often in-
volves learning how to use several equipment items
or performing experiments (such as generation
of fluid property data) which are frequently used
as separate experiments in rotation-type lab
courses. In addition, students can learn from the
oral presentations and laboratory interactions
with classmates. It has been our experience that
the present system stimulates inter-group inter-
action. Feedback from our graduates reinforces
our opinion that the uniqueness of the present ex-
perience far outweighs it drawbacks.
The two major constraints on the lab are
those that are common to many industrial and
academic projects: time and money. Experimental
set-ups are taken apart every year and, not infre-
quently, even after each quarter. New experi-
ments are frequently introduced and old experi-
ments are rotated in and out depending on student
interest. In the second quarter the students are
allowed to select new experiments of particular
interest to them from among those we have the
facilities to implement. As for old experiments,


objectives often are changed for a new lab group
in the second quarter, and may be different enough
that modifications of the apparatus are required.
To this end, we strike a cautious compromise be-
tween our available resources and our creative
urges.
Over the years we have also noticed a certain
latency period in the first quarter of the lab. It
usually takes the students several weeks to adjust
from the cookbook-trained mentality to the point
where they gain the confidence to rely on them-
selves. In several isolated cases we also have to deal
with individuals who are over-enthusiastic and put
unreasonable demands on the technical staff.
Gradually, they all learn to deal with independence,
bureaucracy, lab techs, and fellow group members
who may not have the same motivation or philoso-
phy.
Group dynamics are more obvious in the pres-
ent environment, since the lab group has to go
through so many oral and written reports in ad-
dition to interactions with the project head.
Students with leadership qualities, characters with
nonchalent attitudes, goferss," and any possible
strains within a group are quite observable.

CONCLUSION
We feel that we are successful in developing
the oral and written communication skills of our
students, while providing a forum for innovative
thought. We also have a lab which allows our
students to get acquainted with new industrial
developments, such as microelectronic fabrication
and biotechnology, and with the integration of new
technology, such as microcomputer applications,
into laboratory experiments.
The progress in oral communication skills is
particularly significant and rewarding. We feel it
is a direct result of the fact that each student has
to give a minimum of six talks. (There are ad-
ditional opportunities for oral presentations in the
computer-aided design and process design
courses.) The emphasis is on the student making
a very professional presentation. We have received
quite a number of comments from industrial em-
ployers commending us on the speaking abilities
of our graduates.
The improvement of the writing skills is a
little harder to gauge, even though the students
show obvious progress through the two quarters.
As anyone who has taught a writing class knows,
students have a notoriously high rate of reversion
Continued on page 161.


SUMMER 1985










o M classroom


FUNDAMENTALS OF CHEMICAL PROCESSES

WILLIAM R. MOSER
Worcester Polytechnic Institute
Worcester, MA 10609


THIS COURSE TEACHES the fundamental scientific
principles controlling most chemical, petro-
chemical, and refining processes. The student popu-
lation consists mainly of junior and senior chemi-
cal engineers, but the information is of equal value
to advanced chemistry majors. A few mechanical
engineers interested in plant construction also take
the course. The objective of the course is to pro-
vide the student with a fundamental understand-
ing of the chemical, catalytic and engineering
sciences relating to the chemical reactions taking
place in a variety of reactors of different configura-
tions. Although many major commercial processes
are discussed in the course, the emphasis is not on
an enumeration of all of the major processes, but
the direction is placed on understanding how and
why the chemical transformations occur. This
science is then merged with the technology of the
two dozen or so reactors of radically different de-
signs and configurations currently used com-
mercially. Thus, the student gains an understand-
ing not only of the process fundamentals but also
of the devices used to successfully perform the
processes. The course is kept current each year by
introducing new processes which are in commercial
development. Synthesis gas generation and utiliza-
tion are discussed to address a long range techno-
logical need of engineering and science students.
For the chemical engineering students the course
serves the specific function of allowing them to be-
come more conversant with chemical phenomenon.
This is purposely done in response to the criticism
from both industrial and academic scientists who
feel that the current U.S. training of chemical
engineers is deficient in chemistry. This course has
a chemical orientation but it is placed in the con-
text of learning all of the fundamental sciences
which govern the major commercial processes
which they will deal with in the future. The student
should gain enough fundamental understanding of
the chemical phenomena occurring inside of re-
actors of different designs so that in their future


William R. Moser has been a professor in the chemical engineering
department at Worcester Polytechnic Institute since 1981. Since earn-
ing his graduate degree in 1964 at MIT he has been active in the area
of chemical processing at CIBA, Exxon, and Badger. His research
interests are in mechanistic studies of heterogeneous and homo-
geneous catalyzed reactions using kinetic and in situ spectroscopic
techniques. He has several publications and patents and holds mem-
bership in a number of professional societies.

work they will be able to execute superior process
designs and controls for these or other new pro-
cesses.

COURSE DESCRIPTION
The prior requirements for the course are a
fundamental organic chemistry course, an intro-
ductory inorganic chemistry course (usually in-
cluded in the freshman chemistry series), and a
keen interest in chemical engineering and chemical
processes. Since the course is descriptive and
qualitative, prior chemical engineering courses in-
volving quantitative engineering calculations are
not required.
A successful presentation of the technology de-
scribed by this course requires the application of
several principles of chemical engineering, organic,
inorganic and physical chemistry, thermo-
dynamics, kinetics and mechanical engineering.
Thus, the instructor must make a careful choice
as to the degree of review of these subjects which
is adequate for the understanding of the chemical
process technology. The approach currently used
at WPI is to provide a concise review of just those
principles which are required to master the chemi-
Copyright ChE Division. ASEE, 1985


CHEMICAL ENGINEERING EDUCATION









cal process concepts presented in the lecture of
the day.

LECTURES

The technology presented in the course is ac-
complished in 24 lectures of 50 minute duration.
In addition to outside reading from a list of 89
references taken from the original technical litera-
ture, three term papers are required on topics
which are not discussed in the classroom lectures.
Three one-hour, closed note and closed book exams
are usually given during the duration of the
course. The textbook currently used for the course
is Chemistry of Catalytic Processes by Gates,


Katzer and Schuit (McGraw Hill, 1979).
The course is divided into the following eight
major topics:

1. Survey of Major Chemical and Refining Processes
2. Homogeneous Catalytic Process Fundamentals
3. Heterogeneous Catalytic Process Fundamentals
4. Survey of Modern Commercial Reactor Configura-
tions
5. Synthesis Gas Generation
6. Synthesis Gas Processes for Fuels and Chemicals
7. Technology of Major Advanced Chemical Processes
8. Major Refining Processes

The division of lecture time committed to each
topic may be seen in Table 1. The timing of exams
and due dates for term papers is also shown. A


Lecture
Number
1
2


TABLE 1
Chemical Technology: Course Schedule

13 Reactor Configurations for Major Processes


Subject


Survey Major Chemical Processes
Homogeneous Metal Catalysis
(A) Major Processes


3 Homogeneous Metal Catalysis
(B) Co-ordination Chemistry
(C) Bonding
(D) Reactivity
4 Homogeneous Metal Catalysis
(E) Metals
(F) Stereochemistry
(G) Key Intermediates
5 Homogeneous Metal Catalysis
(H) Key Transformations
6 Homogeneous Metal Catalysis
(I) Ligand Effects on Reactivity
(J) Classification of Reactions
7 Heterogeneous Catalysis
(A) Major Processes
EXAM-HOMOGENEOUS CATALYSIS
FUNDAMENTALS
8 Heterogeneous Catalysis
(B) Surface Adsorption
(C) Surface Kinetics
9 Heterogeneous Catalysis
(D) Surface Chemistry
Problem Set #1 Due-Ziegler-Natta Catalysis

10 Heterogeneous Catalysis
(E) Types of Catalysts

11 Heterogeneous Catalysis
(F) Zeolites and Their Structures

12 Heterogeneous Catalysis
(G) Zeolites and Their Catalysis


14 Synthesis Gas Catalysis and Synthetic Fuels
15 Synthesis Gas Production Processes
(A) Reforming
EXAM-HETEROGENEOUS CATALYSIS
FUNDAMENTALS
16 Synthesis Gas Production Processes
(B) Gasification
(C) Downstream Processing
17 Synthesis Gas for Chemicals and Fuels
(A) Methanol Synthesis
Problem Set #2 Due-Catalytic Cracking
18 Synthesis Gas for Chemicals and Fuels
(B) Methanol to Aromatic Gasoline
(C) ZSM-5 Catalysis
19 Synthesis Gas for Chemicals and Fuels
(D) Fischer-Tropsch Catalysis
20 Synthesis Gas for Chemicals and Fuels
(E) New Syngas Processes for Ethanol, Vinyl
acetate, and acetic anhydride
Problem Set #3 Due-Heterogeneous Partial
Oxidation
21 Synthesis Gas for Chemicals and Fuels
(F) New Syngas Processes for Ethylene Glycol,
Styrene, Xylenes
22 Advanced Technology for Chemical Intermediates
(A) Acetic Acid
EXAM-SYNTHESIS GAS TECHNOLOGY
23 Mature Technology for Chemicals
(A) Wacker Process
(B) Butane Oxidation
(C) Hydroformylation
24 Refining Processes
(A) Hydrodesulfurization
(B) Reforming


SUMMER 1985









brief description of the topics treated in the lec-
tures for the eight major areas listed above
follows.

1. Survey of Major Chemical and Refining Processes
The topic is introduced with a definition of the
four principal types of reactions utilized in com-
mercial reactors, e.g. heterogeneous catalyzed,
homogeneous catalyzed, gas phase catalytic and
non-catalytic, stoichiometric reactions in solution
with their individual variations. Examples are
given for each class. Also terms like conversion,
selectivity, yield, etc., are defined.

2. Homogeneous Catalytic Process Fundamentals
Examples are given of the top fifteen com-
mercial processes using homogeneous catalysts.
The student would be expected to know the re-
actants, products, catalysts, and approximate re-

The objective of the course is to
provide the student with a fundamental
understanding of the chemical, catalytic and
engineering sciences relating to the chemical
reactions taking place in a variety of reactors
of different configurations.

action conditions for each process. Several new
processes which are currently being considered for
commercialization are also listed.
This section includes the important funda-
mental information on homogeneous catalysis.
Thus, the key coordination chemistry principles
required to understand the homogeneous catalyzed
process (to be described later on) are tightly re-
viewed and discussed. A few of the concepts dis-
cussed are: elements of crystal field-molecular
orbital theory; metal d-orbitals; d-electron activa-
tion of coordinated ligands; coordination stereo-
chemistries of transition metal complexes; count-
ing d-electrons; eighteen electron rule; key inter-
mediates in homogeneous catalysis like metal car-
bonyls, hydrides, alkyls, etc.; key transformations
in homogeneous catalysis like oxidative addition,
insertion, electron transfer, etc.; ligand electronic
and steric effects such as pi-acceptors, sigma-
donors, cone angles, etc. Then the basic sub-classi-
fication of homogeneous metal catalyzed reactions
like main group and transition metal catalysis, bio-
catalysis, phase transfer catalysis, polymer sup-
ported catalysis, etc., are briefly described. The
typical kinetic treatments and methods for spectro-
scopic analysis are also illustrated.


3. Heterogeneous Catalytic Process Fundamentals
Fifteen examples are given of major com-
mercial processes in terms of reactants, products,
catalysts, and conditions, along with a brief dis-
cussion of a dozen other processes.
The fundamental aspects of heterogeneous
catalyzed processes are discussed by reviewing
principles of the chemistry and physics of surfaces
and surface adsorption, e.g. macro- and micro-
pores, Knudsen diffusion, chemisorption and physi-
cal adsorption; Langmuir-Hinshelwood and Ri-
deal-Eley surfaces kinetic models, competitive
chemisorption and catalyst poisoning; surface
intermediates and surface chemistry.
This section also discusses the major sub-
categories of heterogeneous catalysts like support-
ed and unsupported reduced metals, solid state in-
organic catalysts, carbon catalysts, clays and zeo-
lite catalysts. Several examples are given for each
class.
A detailed discussion is devoted to the struc-
ture, physical and chemical properties, and cataly-
tic properties of zeolites. Some of the topics dis-
cussed are X- and Y-type zeolites and ZSM-5 struc-
tures, modifications and molecular build up; pore
openings and crystal structure; super acidity and
super basicity; and a four component model for
rationalizing the unusual activity of zeolite cata-
lysts. The student is also introduced at this point
to the relationship of shape selectivity and con-
straint index to the crystal and catalytic proper-
ties of zeolites. An assortment of several classes
of zeolite structures is illustrated with 35 mm
slides and three dimensional molecular models.
Support materials used in heterogeneous catalyzed
processes and their criteria for selection are briefly
discussed.

4. Survey of Modern Commercial Reactor Configurations
Drawings of fourteen of the reactor configura-
tions used commercially in both heterogeneous and
homogeneous catalyzed processes are supplied to
the student, and an example is given of a com-
mercial product produced using each configura-
tion. Within the discussion of these reactor con-
figurations, the various thermodynamic, heat
transfer, kinetic, reactor stability, mixing and
other factors giving rise to the selection of a spe-
cific configuration, are examined. Specific
examples of reactor configurations (process ap-
plications) are as follows: tube and shell (Lurgi
methanol and ethylene oxide process) ; tray re-


CHEMICAL ENGINEERING EDUCATION









actor with interstate cooling (ICI methanol syn-
thesis) ; riser tube (catalytic cracking) ; fluidized
bed (SOHIO acrylonitrile); slurry tank (poly-
propylene) ; radial bed (styrene synthesis) ; and
others.

5. Synthesis Gas Generation

The major processes used in the production
of synthesis gas are discussed along with their
feedstocks and gaseous product compositions. The
thermochemistry of each process is related to
thermal and pressure effects on the syngas pro-
duct ratios and to its consequence on the reactor
design. Drawings for several process reactors such
as methane reforming, partial oxidation, Lurgi
non-slagging gasifier, Koppers-Totzek gasifiers
and the Bi-Gas slagging gasifier are provided to
the student along with a discussion of each. A
survey of next generation gasifiers is given.
Post gasifier processing of raw syngas through


water gas shift, bulk and trace sulfur removal pro-
cesses, CO, removal and CO separation from H2
is discussed. The chemistry of a Claus plant and
Stretford plant is summarized.

6. Synthesis Gas Processes for Fuels and Chemicals

A survey of all commercial and potential fuels
and chemicals processes using a syngas feedstock
is given with reactants, products, catalysts, and
reaction conditions. Details of the thermochemis-
try of methanol synthesis and its consequence on
the evolution of the ICI, Lurgi and Chem Systems
reactor and process configurations are discussed.
The student is introduced to conventions used in
process stream notations. The low pressure
catalyst structure and syngas to methanol surface
reaction mechanism are presented.
A detailed discussion is given to the conversion
of methanol by the Mobil M process to aromatic
fuels. The details of the ZSM-5 catalyst structure,


TABLE 2
Exam: Heterogeneous Catalysis Fundamentals and Commercial Reactor Configurations


Part 1. Describe the following commercial processes using
structural formulae of starting materials, major
products and heterogeneous catalysts required in
the process
(A) Sohio Ammoxidation
(B) Styrene Process (Two Steps)
(C) Maleic Anhydride Process
(D) Catalytic Hydrodesulfurization Process
(C) Fischer-Tropsch Process
(D) Mobil M Process
Part 2. A. Describe the following adsorption processes
for gaseous molecules on catalytic solid surfaces.
Give examples of each.
1. Physical Adsorption
2. Chemisorption
3. Competitive Chemisorption
B. Briefly describe how a Langmuir-Hinshelwood
surface kinetic mechanism differs from a Rideal-
Eley mechanism. Give an example of each.
Part 3. Draw the structural formulae of the following
heterogeneous catalytic surface intermediates
(A) Surface alkyl
(B) Selective surface oxidant
(C) Non-selective surface oxidant
(D) Surface hydroxy Carbene
(E) Bronsted acid surface site
Part 4. Discuss the following properties of zeolites
(A) Compare the 3A, 4A and 5A molecular
sieves in terms of
(1) ions used to modify these zeolites
(2) size of pore opening for each


(3) example of molecules absorbed by each
(B) Briefly compare the structures and differ-
ences in composition of the X- and Y-type zeo-
lites.
(C) Describe the "Supercage" in a com-
mercial catalytic cracking catalyst in terms of
(1) its geometric form and number of sides
(2) size of its largest pore opening and (3)
internal cage size.
(D) Why are zeolite catalysts as much as
10,000 times more reactive than amorphous
aluminosilicates in catalytic cracking?
Part 5. (A) Sketch the reactor section for a commercial
radial bed reactor showing the inlet reactant and
product effluent locations and catalyst bed con-
figuration.

(B) Why would one use such a complex reactor
configuration in a commercial process?

(C) Sketch the reactor configuration for a typi-
cal trickle bed reactor used in catalytic hydro-
sulfurization in a refinery.

(D) What essential task does the trickle bed re-
actor perform which other designs do not ac-
complish.
(E) What is a typical contact time in a riser
tube reactor and which of the following catalysts
would a refiner use in this reactor for catalytic
cracking: (a) ZSM-5, (b) X-type zeolite, (c) Ca-
Y-type or (d) rare earth-Y-type?


SUMMER 1985








acidity, and shape selectivity are merged with a
detailed evaluation of an intercrystalline surface
mechanism to understand the product distribution
and catalyst stability.
A thorough discussion is devoted to the ARGE
fixed bed and fluidized bed SASOL processes for
the direct conversion of syngas to fuels. Catalysts,
reactor configurations, slides of the Sasol II Plant,
surface reaction mechanistic models, Schulz-Flory
kinetics and thermochemistry of syngas conver-
sion to various products are parts of these lec-
tures.
The lectures on the conversion of synthesis gas
to chemicals is less oriented toward reactors and
total processes; rather, they concentrate more on
the detailed reaction mechanisms, using the per-
tinent coordination chemistry intermediates, to
rationalize the conversion of syngas to various
products. This is the first opportunity that the
student has in the course to apply the funda-
mentals learned earlier to homogeneous and
heterogeneous catalyzed processes. Some of the
processes discussed are: acetic anhydride, acetic
acid, ethylene glycol, vinyl acetate, and ethanol.

7. Technology of Major Advanced Chemical Processes
This section also concentrates on reaction
mechanisms for both homogeneous and hetero-
geneous catalyzed processes. Aromatic side chain
oxidation and butane oxidation to acetic acid are
described by listing each of the proposed indi-
vidual, elementary reactions required to form pro-
ducts. The coordination chemistry of the Wacker
process, Carbide and Shell oxo-processes, Halcon
propylene oxide process and others are illustrated.
Likewise, the proposed surface mechanisms for the
super basic zeolite catalyzed conversion of toluene
and methanol to styrene and ZSM-5 zeolite
catalysts for p-xylene production are explored
along with several other.

8. Major Refining Processes
The principal processes utilized in a modern
refinery are surveyed. A few of the processes like
hydrodesulfurization are described in detail by
way of an examination of the crystal chemistry of
the catalyst, processing of various feedstocks, and
reactor configuration. Most of the students' under-
standing of catalytic reforming, and catalytic
cracking comes from assigned textbook reading.
Several of the processes are viewed by 35 mm
slides of various refinery units.


TERM PAPERS

Three term papers are assigned for the purpose
of examining the details of several important
areas of chemical and petroleum processing tech-
nology which are not covered in class. The empha-
sis in the papers is to provide a concise descrip-
tion of the major scientific and engineering aspects
of the technology. In the past, Ziegler-Natta
catalysis, catalytic cracking, and technology of
heterogeneous, hydrocarbon partial oxidation
were assigned.


EXAMS
Three one-hour exams are usually given which
cover all material discussed in class. These exams
are closed notes and books and are given soon
after the subject matter is discussed in class.
No comprehensive final has been given until now.
Table 2 shows a typical exam, given in March of
1982. The high grade was 99, the low was 41, and
the class average of 53 students was 70. O


JUNIOR YEAR LAB
Continued from page 127.

thanks go to Colin Pritchard, Norman Macleod,
Mike Davidson, Jack Ponton, Don Glass, Leong
Yeow and Jeff Lewis.


REFERENCES
1. Macleod, N., and R. B. Todd, Int. J. Heat Mass
Transfer, 16, 485, 1973.
2. Kapur, D. N., and N. Macleod, Ibid, 17, 1151, 1974.
3. Paterson, W. R., R. A. College, J. I. Macnab, J. A.
Joy, to be submitted to ibid, 1985.
4. Paterson, W. R., A. K. Banerjee, N. P. Clark, D. C.
Knott, N. P. Wooley, to be submitted 1985.
5. Scholtz, M. T. and O. Trass, AIChE J, 9, 548, 1963.
6. Bennett, C. 0. and J. E. Myers, Momentum, Heat
and Mass Transfer, 3rd ed., McGraw-Hill, Japan,
p 516-7, 1982.
7. Gover, T. A., J. Chem. Educ., 44, 409, 1967.
8. Crosby, E. J., Experiments in Transport Phenomena,
Wiley, NY, p 139, 1965.
9. Bird, R. B., W. E. Stewart, E. N. Lightfoot, Trans-
port Phenomena, Wiley, NY, p 594, 1960.
10. Williams, R. D., Chem. Eng. Educ., Winter, 28, 1974.
11. Paterson, W. R. and D. L. Creswell, Proc. 4th Int./
6th Europ. Symp. Chem. Rn. Eng., Heidelberg, p
121, 1976.
12. Creswell, D. L. and A. M. Santos, Chem. Eng. Sci.,
35, 283,1980.


CHEMICAL ENGINEERING EDUCATION








LETTER TO THE EDITOR
Continued from page 135.
Another important refinement is to modify the
impeller in the "mixer" which is a small centri-
fugal pump that blends together the reactant
streams entering the reactor tube. In our particu-
lar reactor geometry, the impeller of the pump
sent rapid pressure pulses back to the dye rota-
meter causing violent fluctuations of the bead in
the dye rotameter. Our solution was to replace the
impeller blade with a flat disc. The rotation of the
disc generates sufficient shear to blend the
streams.
R. R. Hudgins
University of Waterloo


PACKAGED SOFTWARE
Continued from page 147.
these packages. To this end an increased student
awareness and familiarity with these facilities
can only be beneficial. OE

ACKNOWLEDGMENTS
The author wishes to acknowledge assistance
and co-operation from the following members of
staff: A. M. Gerrard, J. Notman (Department of
Chemical Engineering), P. R. Bunn (Department
of Electrical, Instrumentation and Control Engi-
neering), and research students J. C. Cheow, S.
Acey, and C. K. Goh.

REFERENCES
1. "Control of a Gas Absorption Column using the
Self Tuning Regulator," C. K. Goh, J. C. Cheow,
P. R. Bunn, and B. Buxton. Paper presented at Insti-
tute of Measurement and Control Symposium "Ap-
plication of Multivariable System Techniques", 31
October to 2 November 1984, Plymouth, UK.
2. Annual Research Meeting, Bath, 4 April 1984. Heat
Transfer, Catalysis and Catalytic Reactors, 247.
Heavy Oil Cracking. S. Acey, J. C. K. Lee, J. R. Walls.


PROCESS LAB
Continued from page 155.
to bad habits as soon as they stop writing regular-
ly.
The feedback from the students has been ex-
tremely positive. They fully enjoy the opportuni-
ty to work on what they regard as their own
problems. We have not come across a course which


puts so much demand on the students but receives
so few complaints. (The actual lab work extends
well over the regular six hours per week scheduled
in addition to the time required for report writing
and preparing oral reports.)
The support from industry has also been en-
couraging. We continually receive financial aid and
equipment donations as well as new ideas for ex-
periments. In the next year we expect to receive
an industrial scale CVD reactor, a spin coating ap-
paratus and an experiment to perform membrane
separation of gasses. Our lab course would not
have been so successful without this continued
support. D

ACKNOWLEDGMENTS
We would like to thank our industrial support-
ers-Chevron, Kelco, Eastman Kodak, and Komax
-for their donations of equipment, materials, in-
formation, and money. Finally, we are indebted
to the AMES department technical support staff-
Joe Robison, Paul Engstrom, Ray Hummer, and
Jon Haugdahl-for their continued help and
understanding (both with students and instruc-
tors!).



REVIEW: Cost Engineering
Continued from page 119.
other new topics added to the first edition such
as an analysis of overtime costs, information on
rework costs, and the handling of back charges.
These topics are illustrated by actual industrial
examples. Additional new information on bulk
material control, monitoring construction field
labor overhead, labor productivity, and forecast-
ing direct labor are illustrated with other in-
dustrial examples. The chapter on contingency
estimating and its application to cost control has
been rewritten to reflect recent developments. The
treatment of estimate types and accuracies like-
wise has been updated. Because of the omnipres-
ent computer, an introduction to computerized
estimating has been added since the first edition.
Advice is provided on how to go about computeriz-
ing routine estimating tasks.
This edition is the first book in a planned
series of about 20 which concern cost engineering
and related topics. Of the twenty, six have al-
ready been published. This series will cover the
whole gamut of cost engineering topics for the
student and for the practicing cost engineer. D


SUMMER 1985









views and opinions


ADJUNCT POSITION

One Way to Keep Up With Technology and Education


RICHARD D. NOBLE
University of Colorado
Boulder, CO 80309

A GREAT DILEMMA IN engineering education is
how an individual can become an excellent
teacher and also keep up with the latest technical
developments in his field. This is especially diffi-
cult during this present period of rapid techno-
logical advance in many fields, such as computers,
and the emergence of new fields, such as biotech-
nology.
What are some of the problems associated with
an academic professional keeping up in both
technology and education? An instructor normally
has had little or no formal training in educational
skills. Also, at many schools there is a lack of
emphasis and a lack of rewards for good teaching.
This makes it difficult for an individual to develop
the necessary skills to be a good teacher. In
technical research, the emphasis at many universi-
ties is to obtain contract research. This in itself
is a difficult task. Once the funding is obtained,
it may be very difficult to perform good work due
to a lack of graduate students, poor laboratory
and/or computer facilities, or an inadequate li-
brary.
There are many possible avenues to solving
this problem. Sabbaticals, leaves of absence, con-
sulting, and graduate research are all possible
means for keeping up with technical advances,
while attending educational meetings and semi-
nars can help to improve teaching skills. This paper
describes an approach that the author has used
to keep up with both technology and education:
combining technical work at a national labora-
tory with an adjunct faculty position at a uni-
versity.
At a time when there are still many unfilled
faculty positions, this approach provides one
method to deal with the problem. Some faculty

Copyright ChE Division, ASEE, 1985


TABLE 1
Some Benefits of An Adjunct Position
PROFESSOR
Develop teaching skills
Conduct technical research
Modern facilities
Interaction with students
Publications
12 month salary
EMPLOYER
Employee morale
Public relations
Highly skilled employee
Student labor
Recruitment of students
UNIVERSITY
Inexpensive labor
Additional faculty
Public relations
Added technical skills
STUDENTS
Exposure to modern technology
Work with modern facilities


may view an adjunct position as a temporary (one-
to three-year) method to develop research skills
while still "keeping up" educationally.

THE POSITION AND BENEFIT
I currently have a position as a chemical engi-
neer doing research in mass transfer separations
at a national laboratory. My job description also
allows me to teach one course per semester as an
adjunct faculty member. I teach one graduate
course and one undergraduate course in transport
phenomena (the same subject area as my techni-
cal work). The laboratory allows me time to per-
form my teaching duties and to attend education-
al meetings such as the ASEE annual meeting.
The chemical engineering department pays my
travel expenses to these educational meetings in
lieu of salary. An outline of some benefits is shown
in Table 1.


CHEMICAL ENGINEERING EDUCATION






















Richard D. Noble received his B.E. degree in 1968 and M.E. de-
gree in 1969 from Stevens Institute of Technology. In 1976, he received
his PhD degree from the University of California, Davis. His current
research in liquid membranes, transient heat transfer, and problem
solving skills.


What are the benefits to me? I can continue to
use and improve my teaching skills by continued
teaching and by attendance at educational meet-
ings. I keep up with the material in the area of
transport phenomena by continued teaching and
technical research, and I keep up with the techni-
cal advances in my field by conducting research
and attending technical meetings. I can use up-
to-date facilities to conduct research. I get to inter-
act with both undergraduate and graduate
students and work with them on research projects.
Continued educational and technical work allows
me to publish in educational and technical
journals. I also have a 12-month salary, so I do
not have to develop additional summer support
for myself.
What are the benefits to my employer? First,
they have a happy employee. If I am enjoying my
job, they benefit. They also get the public relations
benefit of demonstrating their support for higher
education by having an adjunct faculty on their
staff. They have an employee who is technically
"up" in his field through continued teaching in his
subject area, and they enjoy the benefits of
"cross-fertilization" through interaction with uni-
versity colleagues. The employee also develops
communication skills through teaching. Students
work at the laboratory for a small salary or for
credit (no salary), so the labor force is inexpensive
and usually productive. Some of the students may
decide to work for the employer upon graduation
because of their work experience, so there is also
a recruitment aspect for the employer.
What are the benefits to the university? They


get "cheap" labor in a time of fiscal restraints and
they get a faculty member in a time of faculty
shortages. They get the public relations benefit of
having teachers who have up-to-date technical
knowledge, and they also get additional technical
skills in their department.
Last, but not least, what are the benefits to the
student? Students are exposed to modern tech-
nology as it is introduced in the classroom by the
adjunct instructor. They have an instructor who
is "up-to-date" and who can translate the concepts
learned in class to new developments in technology.
For students who work with the adjunct professor,
there are added benefits. They get to use modern
"state-of-the-art" equipment, and through their
work they can gain experience in certain jobs and
determine if they wish to pursue them after
graduation. For graduate students, working with
modern facilities can make their work more pro-
ductive since they spend less time reducing data
and maintaining equipment.
There can also be negative aspects to this type
of arrangement. Adjunct faculty have little or no
time to meet with students outside of class. If the
adjunct has had limited training in teaching, the
communication of information between faculty
and students can be impaired. A job such as I
have described requires the full and continuing
support of both the employer and the university.
If that support is lacking, it would be very difficult
to do a good job.

CONCLUSION
Combining technical training with an adjunct
faculty position has been shown to be an effective
mechanism for maintaining technical and educa-
tional skills. Benefits to the individual, the employ-
er, the university, and the student are varied and
important. The particulars of an adjunct position
are often flexible and depend on the interests and
objectives of the parties involved. O

ACKNOWLEDGMENT
This paper was originally presented at the
ASEE Gulf Southwest Regional Conference, Uni-
versity of Houston, March 13, 1982. A revised
version was presented at the ASEE Summer
School for Chemical Engineering Faculty, Uni-
versity of California, Santa Barbara August 1-6,
1982. I am indebted to the many individuals who
have provided comments during these presenta-
tions.


SUMMER 1985









TEACHING PROCESS DESIGN
Continued from page 123.
The cold gas is warmed in the heat exchanger
to 650F and leaves with an enthalpy of 161 Btu/
lb. Since the mass flow is the same on both sides
of the heat exchanger, the enthalpy decrease of
the liquid CO, is the same as the enthalpy in-
crease of the cold gas, which is (161-148) or 13
Btu/lb. The enthalpy of the liquid going to the
valve (and entering the condenser) is now (65-
13) or 52 Btu/lb. So the refrigeration is
45,300(148 52) = 4,350,000 Btu/hr
The student recognizes that the high-pressure
heat exchanger might be expensive (he suggests
that the high pressure liquid would flow through
tubes and the 200 psia gas through the shell) and
doesn't know if the extra 590,000 Btu/hr of re-
frigeration would warrant the cost of this ad-
ditional piece of equipment (he hopes that he will
soon get a course which will enable him to answer
such questions).

DISCUSSION
The possible ramifications of this sort of de-
velopment of a thermo problem are enormous.
But this is a course in thermodynamics and must
move along-there is a lot more subject matter to
cover. The problem has been a good workout in
the use of a Mollier diagram and in the applica-
tion of the first law flow equation to heat transfer
equipment and to a Joule-Thomson expansion, as
well as the calculation of isentropic compression
power. The calculations are simple so as not to
divert the student from the ideas introduced. Ele-
mentary concepts of process design are encounter-
ed (possibly for the first time), and the student
has an opportunity to invent and compare alter-
native process schemes. There is a continuous
feedback from analysis to better design.
There are many angles which can be developed
in the discussion. The book and the course lec-
tures have seemed to suggest that reversible pro-
cesses are highly desirable. What are the ir-
reversible features of the fourth student's flow
sheet? Can they be reduced or eliminated? Can
the common work functions ("availability") be
used to calculate the operation of a wholly re-
versible process. Can a completely reversible pro-
cess be described? Could an expansion engine
be employed? Could the heat exchangers be made
reversible, even with a zero temperature differ-
ence at one end? Is counter-current flow in the


exchangers desirable or necessary? What is the
origin of the stipulation of a 5F minimum
temperature difference? The second student
found the high pressure gas to liquefy partially
in passing through the valve. Is this phenomenon
peculiar to C2,? Could the book formulas for the
Joule-Thomson coefficient be useful? What ex-
perimental procedures were employed to get the
data on which the Mollier chart is based? If we
had had no chart, could we have made useful
calculations? Could we make a similar analysis
for the case of a natural gas well (pure methane;
or 90% methane, 10% ethane)? Would it be
better to use a separate ammonia refrigeration
plant, or possibly some combination of ammonia
refrigeration plus Joule-Thomson expansion of
the gas stream? Where would cooling water come
from in New Mexico? What are water cooling
towers and how do they work? Why 200 psia in
the pipeline? Etc., ad infinitum.

DIFFICULTIES OF THIS APPROACH
The possibility of introducing design thinking
into theoretical subjects depends primarily on the
interest and competence of the instructor. It can
be done, for some M.I.T. instructors have been
doing it for years. My department's most success-
ful teacher, Dr. W. K. Lewis, has done this sort
of thing all his life. Students in engineering
generally like the approach and find that it helps
them greatly to understand the theory.
The instructor who worries continually about
the things he must "cover" hesitates to "take the
time out" for this sort of discussion. Instructors
often lack the practical engineering background
to do it successfully. Such background (and ma-
terial for good problems) often comes from high-
level engineering consulting work. The rise of
engineering science and the increased consult-
ing work by younger staff members may have
resulted in most of the staff's consulting being
devoted to the more scientific "analysis" kind of
activity, rather than to engineering design. It
might even be suspected that only about half of
the M.I.T. engineering staff are true engineers
in the sense of being competent in design, and that
the reactionn is getting smaller. The most im-
portant single thing M.I.T. can do to improve
the instruction in engineering design is to en-
gage more instructors who are enthusiastic about
the subject and who have not yet become so
enamoured of engineering science that they have
lost interest in design. O


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Full Text

PAGE 1

z 0 <( u ::::, 0 w C) z ci2 w w z (5 z w c,:: 2 w u z < u ci2 w <( u.. 0 z 0 V) > 0 c., z ci2 w w z c., z w _, < u w J: u VOLUME XIX NU MBE R 3 SUMM E R 1985 DENDY SLOAN of the Colorado School of Mines CHEAT UTAH Ar e We Participants or Victims? . WEI T eaching Process Design . . SHERWOOD Innovative Process Lab ROCHEFORT MIDDLEMAN CHAU Teaching Staged Operations . GOLNARAGHI CLANCY GUBBINS Fundamentals of Chemical Processes . . Ad j unct Position CEE INTERNATIONAL MOSER NOBLE ENGLAND : Impact of Packaged Software fo r Process Contro l BU XTON ENGLAND : A Junior ChE L a b . . . . . PATERSON ENGLAND : Recycle With Heating : A Lab Experiment . .. FOORD MASON ISRAEL : Fluid Propert i es and Phase Equilibria . INDIA : On e Month Problem : An Exercise i n Modelling SWITZERLAND SPAIN : I nformation Science . . HERSKOWITZ RAVICHANDRAN KUT QUERALT ROSE

PAGE 2

3M FOUNDATION CHEMICAL ENGINEERING EDUCATION

PAGE 3

EDITORIAL AND BUSINESS ADDRESS Department of Chemical Engineering University of Florida Gainesville, Florida 32611 Editor: Ray Fahien (904) 392-0857 Consulting Editor: Mack Tyner Managing Editor: Carole C. Yocum (904) 392-0861 Publications Board and Regional Advertising Representatives: Chairman: Lee C. Eagleton Pennsylvania State University Past Chairman: Klaus D. Timm erhaus University of Colorado SOUTH: Richard Felder North Carolina State University Jack R. Hopper Lamar University Jam es Fair University of Texas Gary Poehlein Georgia Tech CENTRAL: Robert F. Anderson UOP Process Division Lowell B. Koppel Purdue University WEST: Frederick H. Shair California Institute of Technology NORTHEAST: Angelo J. Perna New Jersey Institute of Technology Stuart W. Churchill University of Pennsylvania Raymond Baddour M.I.T. A. W. Westerberg Carnegie-Mellon University NORTHWEST: Charles Sleicher University of Washington CANADA: Leslie W. Shemilt McMaster University LIBRARY REPRESENTATIVE Thomas W. Weber State University of New York SUMMER 1985 Chemical VOLUME XIX Engineering NUMBER 3 Education SUMMER 1985 The Educator 110 Dendy Sloan of th e Colorado School of Min es, Brodi e Farquhar Department 114 The University of Utah, Norman W. Ryan Views and Opinions 120 162 Are We Participants or Victims?, Jam es Wei Adjunct Position: One Way to K eep Up With Technology and Education, Richard D. Nob l e Classroom 121 132 The Teaching of Process Design, T K. Sherwood Improvem e nts in the Teaching of Staged Operations, Maryam Golnaraghi, Pa u l ette Clancy, K eith E. Gubbins 148 Estimation of Fluid Properties and Phase Equilibria, M. H erskowitz 156 Fundamentals of Chemical Processes, William R. Moser Laboratory 124 136 A Junior Year ChE Laboratory, W R Pat erson Recycle With Heating: A Laboratory Experiment, A. Foord, G Mason 150 An Innovative ChE Process Laboratory, Skip Ro chefort, Stan l ey Middl em an, Pao C Chau Curriculum 128 Basic Information Science Training for Chemical Engine e rs, 0 M. Kut, R. Queralt, L. M. Ros e Feature 144 Impact of Packaged Software for Process Control on Chemical Engineering Education and Research, Brian B uxton Class and Home Problems 140 One Month Problem: An Exercise in Mod e lling, V. Ravichandran 113 Positions Available 118 Book Review 119 Division Activities 135 Letter to the Editor CHEMICAL ENGINEERING EDUCATlON is published quarterly by Chemical Engineering Division, American Society for Engineering Education. The publication is edited at the Chemical Engineering Department University of Florida. Second-class postage is paid at Gainesville, Florida, and at DeLeon Springs, Florida. Correspondence regarding editorial matter, circulation and changes of addre ss should be addressed to the Editor at Gainesville, Florida 326 11. Advertising rates and information are available from the advertising representatives. Plates and other advertising material may be sent directly to the printer: E. 0. Painter Printin g Co., P. 0. Box 877, DeL eo n Springs, Florida 32028. Subscription rate U.S., Canada, and Mexico is $20 per year, $ 16 per year mailed to members of AIChE and of th e ChE Division of ASEE. Bulk subscription rate s to ChE faculty on reque st Writ e for prices on individual back copi es. Copyright 19 86 Chemical Engineering Divis io n of American Socieiy for Engin e ering Education. The sta tements and opinions expressed in this periodical are those of the writers and not necessarily those of the ChE Division of the ASEE which body assumes no responsibility for them. Defective copies replaced if notified within 120 days. The International Organization for Standardization has assigned the code US ISSN 0009-2479 for the identification of this periodical. 109

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[eJ Na educator ~enr4 s~ of the Colorado School of Mines BRODIE FARQUHAR Colorado School of Mines Golden, CO 80401 ~~oENDY SLOAN IS AN academic man for all seasons," said Art Kidnay, department head of Chemical Engineering and Petroleum Re fining at the Colorado School of Mines. "He is one of those rare individuals who does every thing well." Professor Sloan is a renaissance figure, on a campus and in a discipline dominated by special ists. "Dendy is the most balanced, well-rounded faculty member I know," said Kidnay. "That is what sets him apart. Other faculty on campus and around the nation are equally competent in areas like teaching, committee assignments, re search, engineering education research, and work in the professional societies-but I don't know anyone quite as good in all areas." The shelves in Sloan's office contain the usual and the unexpected. Chemical engineering texts and journals dominate, as do two large models of hydrate molecules. What is different is the strong presence of books of philosophy and literature. Books like Zen and the Art of Motorcycle Main tenance by Robert Persig, and Whitehead's The Aims of Education nestle with books by William Shakespeare, Herman Hesse and Robert Frost. The hydrate molecular models represent the specialization Sloan has sought, while the philoso"We're still teaching like Saint Thomas Aquinas in the Thirteenth Century lecturing in front of a group of students. How do we integrate new tools like computers? They are no panacea, yet I believe that the key is in experiential learning, case studies, and real-life problem solving." Copyright ChE D ivisi on, ASEE, 1985 110 phy and literature books represent a curiosity that has never been satisfied with the comfort of settling into a familiar niche. "Dendy teaches a variety of courses," said Kidnay, "and by next year, he will have taught every undergraduate course in our department. He's done this voluntarily. Very few faculty can or would do something like that-most prefer to specialize near their own research interests which makes it easier to teach. I know that som~ schools have a policy to force faculty to rotate through the curriculum in the interest of balance and keeping up with all areas of your discipline. We don't have that policy, simply because most of us don't have the time. Dendy is the only one I know who could pull it off." Born in Seneca, South Carolina, in 1944, Dendy developed an early interest in math science, chemistry, and physics in high school'. He earned his BS in chemical engineering from Clemson University in 1965 and worked five years for duPont, working in Tennessee, Delaware West Virginia, and South Carolina. "In the cours~ o~ those four jobs with duPont," said Sloan, "I discovered that I enjoyed opportunities to be entirely self-motivated and directed. Teaching seemed like a good way to do that." CHEMICAL ENGINEERING EDUCATION

PAGE 5

In light of his later professional accomplish ments, getting into graduate school should not have been a problem. It was. "Dendy did not have outstanding grades as an undergraduate," said his Clemson uppergraduate advisor, Dr Jo seph Mullins. "As I recall, he was active in a band and still plays a pretty hot banjo. The depart ment chairman suggested he take some math courses and reapply Several night courses and A's later, Sloan entered the graduate program at Clemson. "Dendy was the most organized student I've ever had," said Mullins. "He came early and stayed late and ran during the lunch hour. Pretty soon he had most of the grad students chugging away, running with him (Sloan has run 12 marathons and typically has put in 40 miles per week over the past 20 years.) It was at Clemson University that S l oan's role models for teaching made their impact on his career. "Clemson had an unusually strong focus on education," said Sloan "People like Joe Mullins, Dick Harshman, and department chair man Charles Littlejohn had a real impact. As I got into graduate education, I realized that this was what I wanted to do with my life." Sloan earned his MS from Clemson in 1972, with the thesis title of "The Combined Effects of Natural and Forced Convection in a Dual Mem brane, Horizontal Parallel Plate Ultrafilter"; and his PhD in 197 4, with the thesis title of "Non ideality of Binary Adsorbed Mixtures of Benzene and Freon-11 on Highly Graphitized Carbon at 298 15 K and Pressures below 10 Torr." "I advised Dendy to get his PhD elsewhere," said Mullins, "but he insisted on getting it here I did persuade him on the wisdom of doing post doctoral work elsewhere." Elsewhere turned out to be Rice University, where Sloan encountered Dr. Riki Kobayashi and worked as a research fellow on determining the water content of natural gas in equilibrium with hydrates. "It was a very high pressure time and environ ment," said Kobayashi. "Dendy was responsible for measuring and setting the water content specs for a high pressure natural gas pipeline, from Alaska to the lower 48. Dendy, along with Jerry Holder ( currently at the University of Pitts burgh), is currently recognized as one of the primary researchers (in addition to Dr. Koba yashi) in the area of hydrates. The energy crisis really had us going so much so that I bought a rollaway bed for Dendy. He never complained." UMMER 1985 Methane hydrates are a molecular bond of water and natural gas, under pressure. Under certain conditions, hydrates can build up in a pipeline and plug it. From that initial focus on hydrates as a prob lem, Sloan eventually branched out to explore metha n e hydrates as an energy so l ution. R ich fields of methane hydrates exist in deep oceans, as we ll as in per m afrost regions of Canada, Alaska and Siberia. It is estimated that under United States land and territorial waters alone, Once a student l earns the process of learning and solving real-world open-ended problems, he or she will never have to worry about the half-life of his or her knowledge they'll be life-long learners ." there are e n ough hydrate deposits to provide natura l gas supplies for at least 150 years, or 15 times the known supply of conventional natural gas. This unconventional form of natural gas is currently thought of as a future resource, and some of Sloan's research stud i es is currently spon sored by the U.S. Depart m ent of Energy. Sloan ca m e to the Co l orado School of Mines in 1976. Here he taught most of the undergradu ate courses, specializing in ther m odynamics, phase equilibria, and stagewise process design at the graduate level. His research proceeded with natural gas hydrates and included adsorption, phase equilibria, and thermal conductivity. He came for the professional opportunities, the high caliber of st u dents, and the high degree of lati tude Mines offers its faculty, who enjoy both teaching and research. He has stayed for these and other reasons "This is small town America," said Sloan, re ferring to his nine years in Golden. "You have the friendliness of a small community-Cub Scouts, a good church-and access to a big city. This is a good fami l y place." That's important to Sloan and his wife, Marjorie, and his two sons -Trey, 13 and Mark, 10. Sloan has been active in the Scouting movement for six years and has served as an elder in the Presbyterian Church Marjorie is a second year law student at the Uni versity of Colorado. "I've had offers for other positions, yet I haven't been able to convince my self that I'd be happier elsewhere," said Sloan. Has he noticed any similarities between Cub Scouts and college studen t s? E ightto ten-year olds are bundles of unchanneled energy. You've

PAGE 6

got to plan things that will hold their interest; otherwise they climb the walls. Students 18-22 years old are generally very bright and very channeled," said Sloan. "Graduate student per sonalities typically mirror those of the professor, but undergraduates can be a substantially differ ent challenge. Working with undergraduates is one of the best motivators for coming into this profession, and when a school has as good Sloan and his Cub Scout troop getting ready for the big race. students as CSM does, it makes teaching doubly pleasurable." Evidently, his ability to hold an eight-year old's attentlon has rubbed off on his college teach ing style. Students consistently rank him as one of the best teachers on campus, year after year. His peers have also recognized his teaching skills by honoring him with the AMOCO Teaching Ex cellence Award at CSM, and with the Western Electric Award from ASEE. Currently, Sloan works with eleven graduate students in research focused on natural gas hydrates, vapor liquid equilibrium, and thermal conductivity. In 1982, Dr. Sloan acquired the first We8tern sample of methane hydrates when the Glomar Challenger brought up samples from the ocean floor off the coast of Guatemala. Shipped in chilled and pressurized containers to Sloan, the "dirty snowballs" have been divided up among laboratories at CSM and other schools. Sloan and his graduate students are trying to determine optimum in situ methods of releasing condensed methane molecules from the water molecules which surround them. One of the frustrations of running a success ful research operation is lack of time for personal, 112 hands-on research. "We come in as researchers and become research managers. There is no time for lab work. I find time for some theoretical and computer work, but I really miss working in the lab," said Sloan. In spite of these limitations, Sloan does find time for a number of other activities. These in clude professional service in the ASEE and other organizations, service on a variety of CSM com mittees, work with the innovative EPICS pro gram at Mines, plus pondering philosophies of engineering education. He even finds time to study the personalities of faculty and students, correlat ing results with their career tracks. Within the ASEE itself, Sloan is currently Chairman of the Educational Research and Methods Division and is Chairman-Elect for the Chemical Engineering Division. Within CSM, Sloan has served as chairman of the Honors Hu manities Tutorial Committee, and served on the Presidential Search Committee. "EPICS" stands for Engineering Practices Introductory Course Sequence. Because the best method for mastery of any skill is regular practice, EPICS has been designed by Sloan and other CSM faculty as a unique lab-type course, providing "real-world" environments to develop and practice engineering skills. "The emphasis is on the process of learning, not the content of engi neering facts and figures. All the facts, figures and cookbook procedures we pound into students' heads have a half-life, a limited time-span of value, due to the explosion of information and re search. Once a student learns the process of learn ing and solving real-world, open-ended problems, he or she will never have to worry about the half life of his or her knowledge-they'll be life-long learners," said Sloan. "We're still teaching like Saint Thomas Aquinas in the Thirteenth Century, lecturing in front of a group of students. How do we inte grate new tools like computers? They are no panacea, yet I believe that the key is in ex periential learning, case studies, and real-life problem solving. Mines and Harvey Mudd are two of the best places I know that are working toward this new approach of engineering education," said Sloan. The shift from content to process will not come easily, warned Sloan. "High school teachers put a great deal of emphasis on content (students regurgitating books and lectures), as do colleges, yet we expect colleges to produce leaders and inCHEMICAL ENGINEERING EDUCATION

PAGE 7

novators. Giving up emphasis on content is very threatening. It forces teachers to continually learn new materials, use new tools, and to do re search. It forces us to think." It also forces educators to look closely at how students feel about the process of learning. "I'm convinced that if a student leaves a course or a school feeling badly, then we've done permanent damage to that student. He / she won't be as good an engineer as someone who left a course or school excited about what they learned. As a profession, we're not doing a good job of addressing this issue." Sloan enjoys reading philosophy and does not see the discrepancy between the "real world" and the "world of ideas." For Sloan, engineering and philosophy are both concerned with open-ended problems. "I try to see things as part of a spec trum, not as different or isolated from the whole. Take Robert Persig's Zen and the Art of Motor cycle Maintenance. It presents the classic struggle between objective science and intuitive romance and shows that rather than being estranged from each other, they can be part of a whole," said Sloan. Personality types fit into this world view. Using the Myers-Briggs Type Indicator (MBTI), Sloan has found that different personalities have different world views and are attracted to differ ent disciplines (see "Applications of Psychologi cal Types in Engineering Education", February 1983, Engineering Education). Some people are attuned to the practical, hands-on, common-sense view of events, while others are more attuned to the complex inter actions, theoretical implications or new possi bilities of events. These two styles of information gathering, or perception, are known as Sensing and Intuition, respectively. "Since faculty are predominantly intuitive," said Sloan, "and students are evenly split, I'm concerned that we may be awarding grades based on personality characteristics, rather than per formance." Intuitives do better on exams prepared by intuitive type faculty while sensing types do less well-usually because they re-read every test problem in the interest of accurate compre hension, and run out of time. For Sloan, balance or integration is a key con cept. Just as a mature personality should be able to integrate intuitive and sensing methods of learning, a mature profession ( engineering edu cation) should be able to integrate content and SUMMER 1985 POSITIONS AVAILABLE MICHIGAN STATE UNIVERSITY Chemical Engineering ... Tenure system faculty positions. Doctorate in Chemical Engineering or closely related field. A strong commitment to teaching and the ability to de velop a quality research program is expected. Preference will be given to candidates with research interests in the areas of Biochemical Engineering, Surface Science, Solid State Phenomena, or Polymeric Materials. However, ap plicants with outstanding credentials and research interests in other fields related to Chemical Engineering are en couraged to apply. Teaching and / or industrial experience desirable but not essential. Michigan State University is an affirmative action-equal opportunity employer and wel comes applications from women and minority groups. Send applications and names of references to Chairperson, Faculty Search Committee, Department of Chemical Engi neering, Michigan State University, East Lansing, Michi gan 48824-1226. CHEMICAL ENGINEERING / MICHIGAN BIOTECHNI CAL INSTITUTE Assistant / Associate / Full Professor (full year, full time, tenure system). Biochemical engineer ing positions and Distinguished Research Professorship. The Chemical Engineering Department and the Michigan Biotechnology Institute have joint tenure system positions open. Rank, salary and incentives commensurate with qualifications. Applicants should have demonstrated ability in one or more of the following areas. Bioreactor Design and Scale-up; Product Separation and Recovery from Cell Culture Broths; Sensors, Controls and Computer Inter facing of Biological Processes; and Renewable Resource Technology. Strong commitment to applied research plus teaching limited to graduate training in biotechnology ex pected. Applicants with outstanding credentials and an active research program are encouraged to apply. The positions offer the excitement of sharing in both the understanding and rewards of developing new technology. Qualified women and minorities are encouraged to apply. Apply in writing to: Donald K. Anderson, Chairperson, Biotechnology Search and Selection Committee, Michigan State University, 173 Engineering Building, East Lansing, MI 48824-1226. Applications are requested by September 1, 1985, but will be accepted as long as necessary to fill the positions. PROJECT ENGINEERS, Specialty Chemical Manufactur ing Company in Southwest Pennsylvania seeks candidates to direct all process development activities for Emulsion Polymer project. Requirements: Resume, PhD Chemical Engineering plus 2 years experience as Project Engineer or Chemical Research Engineer, PhD and employment ex perience must be in polymer rheology and engineering. $47,088 / year. Full time. Send resume to Charles A. Wilson, Office of Employment Security, 300 Liberty Avenue, Room 1302, Pittsburgh, PA 15222. Job Order #3990818 DOT 4t 019.167-014. process methods of teaching. To all who know him, Dendy Sloan exemplifies a sense of balance and wholeness, as an individual and as a professional educator. 113

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The central part of the University of Utah campus viewed from the northwest. The Merrill Engineering building, glass and aluminum, is below and left of center [eJ n Ii department 1 CHE AT THE UNIVERSIT'I OF UTAH NORMAN W. RYAN Uni ve rsity of Utah Salt Lake City, UT 84112 THE UNIVERSITY OF UTAH, located in Salt Lake City, occupies 1,500 acres and is bounded on the east by the Wasatch Mountains. Founded in 1850, it is the oldest and, with a student popula tion of about 25,000, the largest institution in Utah's system of higher education. Its essential functions are served by a faculty of about 3,500, with roughly half being regular teaching faculty and half being adjunct, research, clinical, and visiting faculty. The governance of the university includes a Board of Regents and an Institutional Council (both appointed by the governor) to wh om the university president reports. The university is a complete university in the 114 sense that it contains a good library and a set of professional colleges (including a renowned medi cal school) with supporting general education and scholarly departments, housed mostly in the colleges of science, humanities, and fine arts. This proximity allows interesting collaboration among the diverse professionals and scholars. The Col lege of Engineering is one of the eleven academic colleges and consists of seven departments, one being the Department of Chemical Engineering. All seven departments of the college are pres ently housed in the Merrill Engineering Building except for what has spilled over as the college has outgrown its building space. Research has ex panded to fill the newly completed Energy and Minerals Research Laboratory Building, and a new classroom building (to be shared with anCopyright ChE D ivision, AS EE, 1 985 CHEMICAL ENGINEERING EDUCATION

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other college) will be available in about a year. The spillover will be reabsorbed, and current needs met. There are rumors about hazards said to exist in associating with the University of Utah; name ly, the seductiveness of the easily accessible out door life in mountains, canyonlands, and deserts. Other enticements to postpone one's urgent duties are afforded by the performances of a symphony orchestra, a ballet company, an opera company, a modern dance company, and several small theatre groups. All are resident in Salt Lake City, and most trace their genesis to the university campus. The locals tend to euphemize the risk of these "hazards" by praising the character-building effects of resisting temptation-but we tolerate (as we practice) yielding with moderation. HISTORY For the present purpose, history is either ancient (1905-1947) or modern (1947-present). In 1905, a program in chemical engineering was first listed among the offerings of the State School of Mines. The first B.S. in chemical engineering was awarded in 1907. By the middle 30's the Chemistry Department was administering the program, but the curriculum was still listed by the School of Mines and Engineering. In 1943 George W. Minard, the first chemical engineer to be recruited, joined the chemistry faculty to supervise the chemical engineering program. Because Selective Service shanghaied his clientele, he took leave to serve in a local war industry, returning full time to graduate the class of 194 7, and then resigning. Modern history begins in 1947 with the fission of the College of Engineering and Mines into the College of Engineering and the College of Mines and Mineral Industries. E. B. Christiansen was retained as head of the new department of chemi cal engineering and was given the choice of affiliating with either of the two colleges. He chose engineering and, despite the fact that some of the top administrators withheld their blessings, hind sight has confirmed the wisdom of the choice. Professor Christiansen, with some initial out side help in teaching, first concentrated on recruit ing faculty and building a projects laboratory. Parts of the apparatus were assembled from war surplus equipment and parts were designed and, to a large extent, built by undergraduate chemical engineering students. After two years the laboraSUMMER 1985 tory was creditable, two new faculty members had joined the faculty, and 37 new BS degrees and the first MS degree had been awarded. The department was ready to apply for accreditation, applied, and was accredited in 1952. During "Modern" times, the regular faculty has grown on the average of one every three years. Of the 15 members signed aboard, only two have left, one by resignation and the other by involun tary transcendental reassignment. Probably, un less the academic charter of the department is altered, the faculty will not be increased much more; future recruits will be replacing those who depart. There are rumors about hazards said to exist in associating with the University of Utah; namely, the seductiveness of the easily accessible outdoor life in mountains, canyonlands, and deserts. The department has attained maturity. Its corporate goals, internally generated, are being acted on competently; its facilities, and now its faculty, are in a steady state of evolution; and its composite personality, which is both varied and dynamic, is progressive FACULTY There are thirteen live bodies on the active faculty, eleven regular, one senior research pro fessor, and one emeritus still active in research. Since part of the efforts of several are devoted to nondepartmental duties, we report only about nine full-time-equivalent faculty. The thirteen mem bers of the faculty ( 14 including a newly hired Assistant Professor) have earned their doctor ates at ten respected universities. All have ex perience in industry and over half have taught elsewhere at the university level. With respect to professional recognition at the national level, one of the faculty, a member of the National Academy of Engineering, is a past presi dent of both the American Institute of Chemical Engineers and the American Institute of Mining and Metallurgical Engineers, two have been awarded the AIChE Founders' Medal, three have been directors of the AIChE, three are Fellows of the Institute, and one was the annual Institute Lecturer for the Institute's Diamond Jubilee year. One has received the NSF "Young Presidential Investigators" award 115

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The spirit has manifested itself in the last seven years in the regional AIChE student paper competition: first place five times, second place five times, third place four times. The Student Chapter Award of Excellence has come to Utah in seven of the last eight years. Two kinds of prized recognition within the university are the awards for outstanding teach ing, five to ChE faculty members, and outstanding research, three to ChE faculty members. All but the newest recruits have served in the less prestigious but important offices and com mittees, national or regional, of the Institute, other professional societies, and governmental agencies. As is appropriate in a university w here the principle of faculty governance of academic matters is nominally respected (though some times needing defense), all faculty serve, or have served, on policy, executive, and administrators' advisory committees. The present faculty members are: Richard C. Aiken (Associate Professor), PhD, 1973, Prince ton University; Alva D. Baer (Professor), PhD, 1959, University of Utah; Richard H. Boyd (Pro fessor), PhD, 1955, MIT; E. B. Christiansen (Pro fessor), PhD, 1945, University of Michigan; Donald A. Dahlstrom (Research Professor), PhD, 1949, Northwestern University; Noel de Nevers (Professor), PhD, 1959, University of Michigan; George R. Hill III (Eimco Professor), PhD, 1946, Cornell; Timothy Oolman (Assistant Pro fessor beginning Autumn 1985), PhD, 1985 University of California, (Berkeley) ; David W. Pershing (Professor), PhD, 1976, University of Arizona; Norman W. Ryan (Professor Emeri tus), ScD, 1949, MIT; Dale L. Salt (Professor), PhD, 1959, University of Delaware; J. D. Seader (Professor), PhD, 1952, University of Wisconsin; Edward M. Trujillo (Associate Professor), PhD, 1975, University of Utah; and A. Lamont Tyler (Professor and Chairman), PhD 1965, Uni versity of Utah. STUDENTS Aside from striving together for an education focused on chemical engineering, our undergradu ate students rely little on the campus to cultivate their social life. Most live off-campus, many have part-time employment in the city and a signifi cant fraction are married. Yet through their shared experiences in classes and in the under graduate seminar, managed by the student AIChE chapter officers, they develop an impressive esprit 116 d e c orps. The spirit has manifested itself in the last seven years in the regional AIChE student paper competition: first place five times, second place five times, third place four times. The national Student Chapter Award of Excellence has come to Utah in seven of the last eight years The chapter's advisor, A. L. Tyler, received one of the National Outstanding Student Chapter Counselor Awards in 1978 and again in 1983. Other interesting sightings of the spirit are made during the annual undergraduate student vs faculty (plus drafted graduate students) basketball game, the junior vs senior softball game, the annual student vs faculty doubles tennis match (in which the faculty remains undefeated), and the spring luncheon at which the seniors are guests of the faculty. On this last occasion the faculty experiences (and sometimes provokes), the students' traditional irreverence, which pass es from calmly suppressed to delicately expressed. With respect to statistical demography, we regularly graduate 35 to 40 students with the bac calaureate each year. The numbers of advanced degrees awarded during the last ten years were 81 Master of Engineering, 27 Master of Science, and 30 Doctor of Philosophy. Our present facili ties and faculty enable us to handle a greater flow of graduate students. UNDERGRADUATE PROGRAM That the curricula of all the chemical engi neering programs in the country are very similar follows from the wide consensus among faculties on the essential ingredients of the overall pro gram. Outside that core of consensus we find differences in emphasis, depth, or diversity. In Utah's chemical engineering, the most notable instance of emphasis is seen in the three quarter senior projects laboratory. Two or three students as a team captained alternately by the members, are assigned eight laboratory projects during the senior year. An assignment is typical ly a design problem which requires that the team operate laboratory equipment to generate the de sign data needed. With assignment in hand, the team identifies appropriate equipment ( or someCHEMICAL ENGINEERING EDUCATION

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times must assemble it), learns how to use it, and determines what data to take. Next they schedule a group oral examination by a faculty supervisor, and when they persuade him that they understand the project, they proceed to the final frustrations : producing the data, using the data, and writing the report. In the course of the year's projects, the student writes three detailed formal reports, a nd his other five reports are technical notes or letter reports. Every report is first read by a non-engi neer who grades it for the mechanics of com position and sometimes rejects it with sugges tions for improvement. When it finally passes the preliminary reading, it goes to the faculty supervisor who will judge its form and engineer ing content. A late report is downgraded sig nificantly. On the other hand, a report reflecting unusual ingenuity in experiment or design is awarded a grade bonus. Another emphasis, perhaps its distinctiveness already swept away by time's frantic broom, has been our use of computers in homework and laboratory instruction. In the laboratory, many experiments are monitored or controlled by microcomputers or minicomputers. In most de partmental courses, computer time is made avail able for the students on the computer center's mainframe computer, and techniques requiring its use have become an integral part of the course work. Of particular note has been leadership, through J. D. Seader, in instruction in the use of large process simulation programs such as ASPEN, FLOWTRAN, and CHEMSHARE. During the final quarter, each student is required to complete a technical and economic design op timization using one of these tools. We do not treat the diffusional processes col lectively as transport phenomena or under other non-descriptive titles. Rather we share with me chanical and civil engineering departments the teaching of common courses in engineering thermodynamics, fluid mechanics, and heat trans fer. The students' class scheduling problems are greatly reduced. The required mass transfer courses are taught only in chemical engineering. Many students desire some specialization, and we try to guide them in choosing the appropriate elective courses. To that end, we have established several informal options such as living systems digital control, and management; or we may ap~ prove alternative schemes of electives proposed by them. SUMMER 1985 GRADUATE PROGRAM Four advanced degrees are offered in the de partment: Master of Engineering (ME), Master of Science (MS), Master of Philosophy (MPhil), and Doctor of Philosophy (PhD) Each aspirant is limited with respect to which of the degrees he may apply for, depending on his performance in a combination diagnostic and screening examina tion. This preliminary judgment may be appealed later on the basis of the student's subsequent per formance. The ME degree, design-oriented, is popular with BS-ChE holders and graduates from related View in the undergraduate Projects Laboratory. fields who want advanced treatment of chemical engineering, with opportunity for further study in related fields or mathematics. Much the same can be said for the MS degree, except that it is research-oriented and it is sometimes a first step to the PhD. The PhD is a research degree for which candidacy is def erred until the aspirant passes a qualifying examination. That examination takes the form of preparing and defending a research proposal in which the prospective candidate is re quired to demonstrate originality and independent thought. The dissertation, with very rare ex ceptions, must exhibit an essential experimental component. RESEARCH Research in Utah's chemical engineering de partment is aimed at the education of degree candidates, with the faculty's role being maximal ly advisory, minimally supervisory. The benefits of the research in faculty development are regard117

PAGE 12

ed as a bonus. Most (if not all) single-author publications by the faculty have not been de signed to present new research findings, but rather have been intended to be either pedagogi cal, critical, or entertaining. A furnace used in research on air pollutant formation. The line of research of greatest longevity in the department has dealt with the rheology of non-Newtonian fluids, both the characterization of detailed fluid motion and its use in describing bulk flow. Related but independent projects have dealt with two-phase flow, with liquids and solids distributed in gases, with solids and gases dis tributed in liquids, and with fluid mechanics and heat transfer for flow in curved tubes with and without chemical reaction. In addition, a study of the fluctuating boundary layer in nominall y "steady-state flow" was made. The research having the longest period of continuous sponsorship, and consequently gener ating the largest number of advanced degrees, has studied the combustion of condensed fuels. The chief interest has been in the transients of ig nition, oscillating combustion, and extinguish ment. Much of the effort has involved the burning of solid composite rocket fuels, and some, the burning of the polymers and oxidants separate ly, with clear relevance to fires. This work quali fied the University of Utah to host the Thirteenth Symposium (International) on Combustion on our campus in 1970. The combustion research activity just men tioned has diminished in intensity. Meanwhile, another class of combustion projects has become the most active. This research involves coupled experimental and theoretical work on the control of acid rain pollutants (primarily NO, N0 2 S0 2 and SO s ) under conditions typical of thvse found 118 in coal-fired industrial furnaces, boilers, and kilns; the direct combustion of biomass fuels; and the incineration of hazardous industrial wastes in rotary kilns. As one would expect in a university so situ ated, there is active research, though with a lesser sense of urgency than expressed a few years ago, on coals, oil shales, and tar sands. They are characterized and variously processed to produce liquid fuels. A recent subject of research which has been a dvanced notably in this department is computer aided process synthesis and design. Methods have been developed for synthesizing multicomponent separation systems based on considerations of second-law analysis. Most recently, robust com putational procedures based on homotopy con tinuation have successfully been applied to inter linked separation systems, with the surprising discovery of multiple solutions. D POSTSCRIPT If the reader ha s residual questions about chemical engineering at the University of Utah, he is invited to correspond with the chairman of the department, Professor A. Lamont Tyler. [i) N :I book reviews APPLIED COST ENGINEERING, 2nd Edition by F. D. Clark and A. B. Loren z oni Marcel Dekker, Inc., 368 pages, $ 3 2 .50 (1985) Reviewed by James H. Black University of Alabama This book is a revised, updated, and expanded version of a very successful (six printings) pre decessor. It is of particular use in explaining how to develop and use cost estimating tools, how to manage and use estimating data, how to avoid estimating pitfalls, and how to solve estimating problems. It also covers such topics as the use of estimates for cost control functions during the conceptual engineering, the detailed engineering, and the construction stages of project develop ment. With the techniques described in this book, one can find out how to measure and forecast pro ductivity and to control, rather than just report, costs. The book emphasizes cost estimating and Continued next page. CHEMICAL ENGINEERING EDUCATION

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CHEMICAL ENGINEERING DIVISION ACTIVITIES TWENTY-THIRD ANNUAL LECTURESHIP AWARD TO DAN LUSS The 1985 ASEE Chemical Engineering Di vision Lecturer was Dan Luss of the University of Houston. The purpose of this award lecture is to recognize and encourage outstanding achievement in an important field of fundamental chemical engineering theory or practice. The 3M Company provides the financial support for this annual lec ture award. Bestowed annually upon a distinguished engi neering educator who delivers the Annual Lecture of the Chemical Engineering Division, the award consists of $1,000 and an engraved certificate. These were presented to this year's Lecturer at the Annual Chemical Engineering Division Ban quet, held at the Georgia Institute of Technology. ChE's RECEIVE HONORS A number of chemical engineering professors have been recognized for their outstanding achievements. Max Peters was the recipient of the Fred Merryfield Design Award, given annually to an engineering educator who exhibits excel lence in teaching engineering design, and the Senior Research Award was presented to Robert Brodkey in recognition of his significant contribu tions to engineering research. Friedrich G. Heffo. rich, Richard D. Noble, and Richard M. Feide r all received AT&T Foundation Awards, honoring cost control, two of the more important aspects of the field of cost engineering. This book would find application as an ad vanced undergraduate-graduate level text in such courses as Process Design and Economics, Cost Engineering, Cost Estimating, Project Manage ment, Project Control, and Construction Manage ment. The first edition has found application this way since its appearance seven years ago, and this revised edition will continue that tradition. Practicing engineers, entering cost estimating for the first time, would find this book an indispens able aid. For convenience, the book has been divided into three parts; namely, cost estimating, cost SUMMER 1985 them as outstanding engineering teachers, while the Dow Outstanding Young Faculty A ward was presented to Marc Donohue, James M. Peterson, and Mark E. Davis. The grade of ASEE Fellow Member was conferred on Ray W. Fabien in recognition of his outstanding achievements and important contributions. NOMINATIONS FOR 1985 AWARD SOLICITED The award is made on an annual basis with nominations being received through February 1, 1986. The full details for the award preparation are contained in the Awards Brochure published by ASEE. Your nominations for the 1985 lecture ship are invited. They should be sent to Professor Angelo J. Perna, New Jersey Institute of Tech nology, Newark, NJ 07102 (201-596-3616). NEW DIVISION OFFICERS The ChE Division officers are: Dendy Sloan, Chairman ; Deran Hanesian, Past Chairman ; Phillip C. Wankat, Chairman Elect; Bill Beckwith, Secretary-Treasurer; and A. Lamont Tyler, Gary Poehlein, and Carol Dedrick, Directors. NEW AWARDS Two new Divisional awards have been es tablished and will be presented at the annual meet ing each year. One, the William H. Corcoran Award, will honor an author for the most outstand ing paper published in Chemical Engineering Education during the preceding year. The second, the Joseph J. Martin Award, has been created to recognize authorship of the best paper published in the proceedings from the prior year. control, and case studies. Part Ill, the case studies, is a collection of ten examples to illustrate the principles of cost engineering. These case studies are designed to provide understanding of the underlying principles discussed in the first two parts of the book. The new features of this book include, in ad dition to the case studies and the latest develop ments and improvements in cost estimating and cost control, several new aspects of cost engi neering so that the book reflects recent advance ments in the field. A new chapter on control of subcontracts has been added because of the in creased importance of this topic today. There are Continued on page 161.

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EDITOR'S NOTE: A contro v ersy is brewing on the design content of the curriculum. The questions are 1) how much design should be required and 2) how does one define ".d~sign"? In order to air ~~ese important questions, CEE is publishing the following two papers. Additional comments are solicited from our readers. leJ;jpjviews and opinions ARE WE PARTICIPANTS OR VICTIMS? JAMES WEI Massachusetts Institute of Technology Cambridge, MA 02139 T HIS CONVERSATION, or something like it, t~ok place at the San Francisco AIChE meetmg among a group of distinguished professors and department chairmen of research universities. "They are making a mess at accreditation ( or choose one from: AIChE, NSF, ACS, ASEE, NAE, etc.). They are just a bunch of bean count ers who do not understand that we should have in novations and diversity. And besides, who are they to tell us that our program is below stand ards? Have they ever managed a first-rate depart ment themselves?" "Why don't you do something about it, suggest changes, organize a group, get involved?" "I am much too busy with my students and papers. Somebody else should do it." (i.e., some body else not as good as we are, say a politician who cannot hack it in research and teaching.) "But these are our own organizations that we depend on. If we won't fix them, who else would do it?" "We can send them an ultimatum, that if they do not shape up, we will quit." "We need to send them a detailed blueprint on how to reform their rotten organization. And if they cannot do it, we will have to start a new organization to administer accreditation to set up new rules, to train new visitors, and to evaluate results. That would be even more work than re form from within." "Of course not, that would take too much time and effort." "You are mad enough to complain, but not enough to do something constructive-like volun teer for service. Shouldn't we take the time to fix up our own organizations? No one else would have the knowledge or motivation to fix them to 120 James Wei received his BChE from Georgia Tech in 1952 and his ScD from M.I.T. in 1955. He graduated from the Advanced Man agement Program at the Harvard Business School in 1969 He is presently Warren K Lewis Professor and Department Head at the Massachusetts Institute of Technology our specifications." "But that would be politics." "For instance, the AIChE Council of 17 con tains only two professors. The accreditation com mittee and the ad hoc visitor list have very few professors from research universities. We believe in a trial by a jury of peers, and our peers are other research universities. If we will not sit on juries, we cannot be tried by a jury of peers-who understand us and are sympathetic to us. We should run for AIChE Council, or volunteer for ad hoc visitor in accreditation." "I am much too busy, and I am not interested in politics." "But politics affects us, and it has us riled up. If we are above politics, would we rather be victims or participants?" "Let us go to the Exxon suite to drown our sorrows." The moral of the story is that it is better to be mugged than to participate in government, or isn't it? Co p y ri ght ChE D ivisi on ASEE, 19 85 CHEMICAL ENGINEERING EDUCATION

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[j n I classroom THE TEACHING OF PROCESS DESIGN EDITOR'S NOTE: The following paper, authored by the late T. K. Sherwood in 1959 while he was a faculty member at M.I.T., was sent to CEE by W. H. (Bill) Manogue, a member of the AIChE Educar tion and Accreditation Committee. He credits E. L. Mongan, Principal Division Consultant in DuPont's Engineering Ser v ice Di v ision, for bringing it to his attention Professor Emeritus J. Edward Vivian of M.l.T. has w ritten Dr. Manogue that he and Professor Wei (Head, Department of Chemical Engineering at M.I.T.) ha v e re v iewed the manuscript and "while,, he agreed with me that Sherwood's conclusion is not current, he felt that as long as the publication ap peared with an Editor's note that this was a historical paper written in 1959, he had no objection to publication of the complete original manuscript." We are pleased to be able to share this historical document with our readers, with the comments above. T. K. SHERWOOD (Deceased) Former professor at Massachusetts Institute of Technology Cambridge, MA 02139 I T IS SUGGESTED that engineering design can be taught effectively by introducing design prob lems into various theoretical subjects. A sample thermo problem is presented in detail as the best means of explaining just how this approach can be used in a course such as engineering thermo dynamics. If this technique is to be more generally em ployed at M.I.T. it is necessary that a large fraction of the engineering faculty be as inter ested and competent in the design aspects of engineering as they are in the scientific or an alytical. The fraction so inclined is perhaps al ready too small and appears to be decreasing. INTRODUCTION The typical engineering accomplishment of importance results from a sequence of (a) recognition of a social need or economic oppor tunity, (b) a conception of a plan as to how the need may be met or the opportunity seized, (c) an analysis of the merits of the conception and of the consequences of proceeding with the plan, (d) the building or construction of the machine, plant or bridge as conceived, and ( e) its opera tion. Item (c) is a sort of go no-go step; if the Copyright C hE D iviBi on, A SEE, 1 985 SUMMER 1985 analysis is discouraging, the conception step and the analysis are repeated "Engineering science" is a phrase which has come into use in recent years to describe the analysis step. Good engineers today must be ex ceedingly proficient in analyzing a concept; quantitative mathematical analysis based on first principles is one of the good engineer's most powerful tools. But it no more constitutes engi neering than any one of the other four activities listed. In particular, it must be noted that con ception ("design") comes before analysis; the analyst must have something to analyze. As technology develops, it seems likely that those engineers who can recognize social needs or economic opportunities and who can conceive and plan will be the men most sought after. They will be the ones who will hire the analysts ( engi neering scientists), the constructors, and the operators. To a large degree this is true today. THESIS The concept ("design") ab ilities of the student may be developed in at least three ways : (a) through design courses, planned to meet the need directly through lectures and exercises ( this is the method used in architecture), (b) by subjects in which design problems are inter woven with the teaching of basic theory, and (c) by sticking to basic theory and the techniques of analysis, letting the student develop his own skill at inventive and conceptual thinking by exposure 121

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The teaching method I have in mind is best understood by studying an actual problem assignment. The example chosen is from engineering thermodynamics. to the ideas and accomplishments of the great creative scientists The teaching of design by method (a) has not been well developed, except in connection with machines, aircraft, and architecture. Method (c) offers little promise for engineering. My thesis is that the second method can and should be more widely used in engineering education. EXPLANATION The teaching method I have in mind is best understood by studying an actual problem assign ment. The example chosen is from engineering thermodynamics, partly because I teach this sub ject, but also because thermodynamics is one of the best examples of a subject that is often taught with no element of engineering design. It is a theo retical subject involving many abstract ideas and is normally expected to require rigorous thinking and exact calculations. ILLUSTRATIVE PROBLEM The following is a typical problem assign ment to juniors about the middle of the first term of a two-term course in chemical engineering thermodynamics. * * * Problem 10 A gas well in New Mexico produces essential ly pure CO 2 at 800 psia and 100 F. The pressure is reduced to 200 psia by flow through a partially closed ("cracked") valve and delivered by pipe line to a plant several miles away. The flow rate is steady at 10 million ft 3 / day (reported as ft 3 at 60 F and 1.0 atm). The Joule-Thomson expansion through the adiabatic valve causes the gas to cool. This cold gas is used to provide refrigeration for a natural gasoline plant located near the wellhead. The con denser to be cooled operates at 60 F, and the minimum temperature difference for heat ex change is 5 F (i.e., the warmed CO 2 leaves at 55 F). a) What is the temperature of the CO 2 leav ing the valve? 122 b) What is the attainable refrigeration load, expressed as BTU / hr? (Comment-note ho w the in stru c to r has made this sound like a practical p r oblem by the word ing. Th i s is pure c amouflage-th e solution is simple and st r aightfor w a r d. The student is not asked to think-only to kno w ho w to use the first la w and the Molli e r d i agram for CO 2 .) Solution From the book, the first law flow equation is found to be Q Wn = Lih As applied to an adiabatic valve Q and W n are zero, so the enthalpy leaving the valve is the same as upstream. This is read from the Mollier diagram to be 146 Btu / lb CO 2 At 200 psia CO 2 has this enthalpy at 5 F, which is the answer to (a). At 55 F and 200 psia the enthalpy is 158 Btu / lb, as read from the chart. In the condenser Lih is 158-146 or 12 Btu / lb CO 2 From the first law flow equation as applied to the condenser Q-0 = Lih so the refrigeration amounts to 12 Btu / lb CO 2 flowing. The specific volume of CO 2 at 60 F and 1.0 atm is read from the chart as 9.2 ft 3 / lb so the CO 2 flow rate is 10,000,000 / 9.2(24) = 45,300 lb / hr The refrigeration load is then 45,300 (12) = 543,000 Btu / hr This is the answer to (b) * * * USE OF THE PROBLEM TO TEACH DESIGN Now consider the problem so reworded as to invite the student to look at the design aspects of the situation. The CO 2 flow rate is specified to be the same as before. The pipe line pressure is 200 psia, as before. Cooling water is available which can be used to cool the CO 2 stream to 70 F. The condens er to be cooled now operates at 20 F ; the cold gas can be warmed only to l5 F so as to maintain the minimum temperature difference of 5 F. The student is now asked : how much refriger ation is attainable from the CO 2 stream? How would the necessary equipment be arranged (i.e., CHEMICAL ENGINEERING EDUCATION

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draw a flow sheet)? The routine M.I.T. "A" or "B" student sees the statement regarding available cooling water, notes that the feed gas is the only thing capable of being cooled to 70 F, and so refigures the prob lem with gas entering the valve at 70 F and 800 psia. Enthalpy values from Mollier chart: feed gas, 146; gas at 800 psia, 70 F, 126; gas at 200 psia, 15 F, 148. Refrigeration is then 45,300 (148-126) = 1,000,000 Btu / hr and 45,300 (146 126) = 906,000 Btu / hr are removed by the cooling wate r The flow sheet is shown in Fig. 1. FEED i CO OL ER ~A. L VE ~CONDENSER GAS ---+ ( ~}-=-=== --+ l 5 F 70 F 800 p sia l lOO O F WATER 2 0 0F FIGURE 1 A second student, probably a "B" or "C" man goes through this same calculation, but in doing so notices that the CO 2 leaving the valve is partly liquefied. This is evidently a good thing. If all the CO 2 could be liquefied, there would be a very large amount of refrigeration. But avail able cooling water limits cooling to 70 F. The chart shows that CO 2 could be liquefied at 70 F if the pressure we r e about 865 psia. The well pressure is only 800 psia. But it should not take much power to compress the feed gas to 865 psia; the pump might be expensive because of the high ope r ating pressure, but would be physically small because the gas density is high and the volu metric displacement low. The second student s flo w sheet is shown in Fig. 2. The compressor is assumed to operate adiabatically and reversibly and the pressure change is assumed to be isentropic. The first law gives the flo w work as -ah, which is read from the chart as approximately 2 Btu / lb. The theo retical power required is 45,300 (2) / 3412 = 26.7 kw 01' 35.6 hp which does not seem like much. The CO 2 now leaves the cooler completely liquefied at 70 F with an enthalpy of only 65 Btu / lb. ah is zero through the valve, so the re frigeration attainable in the condenser is 45,300 (148 65) = 3 760 000 Btu / hr SUMMER 1985 C O OLER CO N DENSER VA L VE -F=i--+ ;B)---r~ l 5 F BOO psia FIGURE 2 The student does not know much about the efficiency or cost of compressors, but he concludes that even if the actual power were twice the theo retical, the compressor installation would appear to be well worth while in view of the very large increase in refrigeration attainable. A third student follows the same reasoning and makes the same calculations as the second, but is troubled by the fact that the chart gives extremely poor precision in reading the ah of 2 Btu / lb in the compressor. He has learned that if kinetic and potential energy terms are neglected ah for reversible flow is given as f vdp Reading the chart, he finds the specific volume HEAT COO L ER EXCHA N GER ~~En' mo~ tl__j ll GAi 65F G A S TO Pl PELINE FIGURE 3 CO N DENSER ~; ~200psia of the feed gas to be 0.115 ft 3 / lb and that of the gas compressed isentropically to 865 psia to be about 0.105. An average value of 0.11 ft 3 / lb cannot be more than 5 % in error, so ah = 0.11 (865 800) (144 / 778) = 1.32 Btu / lb from which he calculates the theoretical (adi abatic reversible) compressor power to be 17.5 kw. A fourth student makes the same calculations as the second or third student, but hates to see the gas go to the pipe line at 15 F. Cannot this c old gas be useful? Water cooling to 70 F certain ly was. Using the cold gas to partially cool the feed gas would only save cooling water. The thing to do, then, is to use the 15 gas to cool the liquid CO 2 leaving the gas-water heat exchanger. His flow sheet is shown in Fig. 3. C ontinued on page 164. 123

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[j ;j a laboratory A JUNIOR YEAR CHE LABORATORY W. R. PATERSON Un iv ersity of Cambridge Cambridge, England CB2 3RA s OME EXPERIMENTS which the author ran in 1980-81 in the University of Edinburgh's third year chemical engineering laboratory are shown in Table 1. Fluid mechanics and thermo dynamics laboratories are taken separately. This is the major chemical engineering formal lab, since the student does research and design pro jects in the fourth year of the course. The students work in pairs, starting at 10 :00 a.m. and finish ing nominally at 5 :00 p m. (in practice, between about 3 :00 and 6 :00 p.m.). The lab runs for two terms. In the third term of the session the weekly lab is omitted and there is a 'lab week' instead where the students devote the whole of one week to an open-ended short project, such as the de velopment of a new lab experiment. This paper remarks on features of the experiments which might make them attractive for wider use. CONVECTIVE MASS AND HEAT TRANSFER Good convective mass transfer experiments are hard to find. This writer's experience with wetted wall columns, for instance, has not been happy. The purpose of this experiment is not the study of simultaneous heat and mass transfer, but the study separately of convective heat and mass transfer in the same geometry, to allow the j-factor analogy to be confirmed. The apparatus was originally a commercial heat transfer experi ment, consisting of a 12.5 cm square duct with a perspex test section, through which air is drawn by a blower. Transverse rods of 1.25 cm diameter The purpose of this experiment is not the study of simultaneous heat and mass transfer, but the study separately of convective heat and mass transfer in the same geometry, to allow the j-factor analogy to be confirmed. C opy ri gh t ChE D iviBi on A SEE, 19 85 124 TABLE 1 LIST OF EXPERIMENTS (1982) Topic: Principal Measurement Method; Ancillary Equipment 1. Plate Heat Exchanger: Thermocouple 2. Film and Nucleate boiling: Thermocouple; Ammeter 3 Double Pipe Heat Exchanger: Thermocouple; Wei g h Tank 4 Single Tube Condenser: Thermometer 5. Heat Transfer to a Jet: Liquid Crystal Sheet 6 Jacketed Pans: Thermometer; Weigh Tank 7. Process Control: Float; Micro-computer 8 Convective Mass and Heat Transfer: Balance Thermo couple; Chart Recorder 9. Continuous Still: Densitometer 10. Continuous Liquid-Liquid Extraction: Titration 11. Drying: Continuous Weighing; Anemometer 12. Filtration: Volumetric Cylinder; Filter Leaf 13. Packed Tower Hydraulics: Manometer 14. Fluidised Beds: Manometer; Weigh Scales 15. Diffusion-Closed System: Ga s Liquid Chromatography; Recorder and Integrator 16. Diffusion-open system: Katharometer; Chart Recorder 17. Measurement of Surface Area of Alumina: B.E.T. Ap paratus; Liquid N 2 18. Packed Bed Catalytic Reactor: Gas Liquid Chroma tography ; Recorder and Integrator 19. Adiabatic Batch Reactor: Thermocouple; M i cro-computer 20. Enzyme Catalysis: Polarimeter 21. C.S.T.R.: Spectrophotometer 22. Residence Time Distribution Study: Flame Ionisation Detector; Micro-computer 23. Coagulation: Pressure Transducer; Chart Recorder are introduced through holes in the wall, to simu late up to four rows of a heat e x changer tube bank: all the rods but one are pe rs pex dummie s The working rod is coppe r and has a thermo couple within it. This rod is heated electrically and then inserted into place at the start of the ex periment. From its cooling curve the gas-rod heat transfer coefficient is deduced, and the experi ment is repeated for different air velocities and test-rod positions Measured pressure drops are also logged. Next, the mass transfer runs are per formed. The adaption to mass transfer work exploits CHEMICAL ENGINEERING EDUCATION

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Bill Paterson lectured at Edinburgh after taking his BSc and PhD there. He has been a development manager with I.C.I. Petro chemicals Division and is now a University Lecturer i n chemical engineering and Director of Studies in chemical engineering at Corpus Christi and Sidney Sussex Colleges, Cambridge. His research interests include chemical reaction engineering, packed bed operations, flow sheet simulation and process synthesis Macleod's swollen polymer method [1, 2]. A thin film of commercial silicone rubber is deposited on the surface of the mass transfer working rod. This is swollen to equilibrium with some suitable volatile agent, e .g ethyl salicylate. When the rod is placed in the air stream the agent evaporates. There is a constant rate drying period during which the partial pressure of the swelling agent immediately above the polymer is sensibly con stant, equal to its saturated vapour pressure at the air temperature, and the controlling mass transfer resistance is rod-gas convection; diffu sion through the polymer does not intrude. Inter mittent withdrawal and weighing of the rod both establishes the mass transfer rate (and thus the mass transfer coefficient, for the partial pressure of swelling agent in the bulk gas is virtually zero) and confirms that the test is within the constant rate period. The rod can then be immersed in a test-tube of swelling agent for re-swelling to equilibrium, while a different test rod, ready pre pared, is used for the next run. Since saturated vapour pressure is sensitive to temperature, it is important to measure the air temperature with more accuracy (e.g., + 0.1 C) than the heat transfer experiment requires. The transfer coefficients are then nondimen sionalised, to show that the restricted j factor anology, h = jH, holds, while the presence of form drag falsifies the complete j factor analogy jn = jH = f / 2, where f is the friction factor. Alterna tive swelling agents, appropriate values of satur ated vapour pressure and diffusivity, and other simple experiments using the swollen polymer SUMMER 1985 method are reported elsewhere [3, 4]. HEAT TRANSFER TO A JET A flat horizontal sheet of plastic, of area A, incorporating a commercial liquid-crystal temp erature-sensitive film, is heated from below by direct contact with an electric heating mat. The relation between sheet temperature and colour is established in preliminary experiments. The mat sits on insulating material so that all its power, W, measured as current times voltage, passes through the sheet. The sheet quickly reaches a thermal steady state, so that, in still air, it has a uniform colour. A round, laminar air jet is then aimed at the centre of the sheet, normal to its surface. Then, since the solid-air heat transfer Good convective mass transfer experiments are hard to find. This writer's experience with wetted wall columns, for instance, has not been happy. coefficient, h, varies with position, r, so does the surface temperature of the film, T and coloured rings appear on the film. The heat transfer co efficient, as a function of r, is calculated from h(r) = W / A[T T (r)] and compared with theory [5] Nu(r) = 0.159 Pr 1 l 3 Re 3 l 4 (d / r) 5 / 4 where d is the diameter of the jet. The experiment is repeated with a square jet for which no theory exists, and the students ex plore the unexpected and interesting results. An improved and abbreviated (two hour) form of this experiment has been transplanted to the second-year fluid mechanics and transport pro cesses lab in Cambridge. Details may be had by writing to Mr. N. MacFadyen. DIFFUSION EXPERIMENTS Usefully accurate gas diffusivity measure ments can readily be made in a Stefan experi ment [6] where evaporation rates are measured from a long-necked flask. However, this experi ment does not involve the direct measurement of concentration profiles and is consequently found unsatisfactory by some students. The two ex periments used in this lab are selected to remedy this defect, to show the difference between equi molecular counter-diffusion and diffusion through 125

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a stagnant film, and to introduce the student to some moderately heavy mathematics and to some analytical instruments. The counter-diffusion experiment is Gover's [7]. About 5 ml of, e.g., acetone vapour is injected through a septum near the bottom of a vertical, lagged sealed glass tube ( length ca 60 cm, i.d. 2.5 cm) containing, as host gas, nitrogen traced with 3 % ethane. A subsequent series of analyses of samples withdrawn (by 100 l gas-tight syringes) at two sample points each located at one-sixth of a tube length from an end permits determination of DAB, the diffusivity of the va pour in nitrogen. The acetone concentration in counter-diffusion is described by the diffusion equation (Fick's second law) aC.A D 0 2 CA AB with t = 0, CA (Z) = CA O (Z) z = o,L, aCA / aZ = o where Z is the axial coordinate, t is time, and L is the tube length. The solution for t > 0 is obtained by separation of variables CA(Z,t)=Ao+ IAkexp{ {~f DABt )cosk~Z where the values of the coefficients A o ... Aoo de pend on the initial concentration CA O (Z), that is, on the particular Z-wise concentration profile set up on completion of injection (t = 0). Taking the difference of concentration be tween two points at the same time, the even terms cancel and the odd terms double. The lo cation of the sample points causes the term in A a also to vanish, while the decaying exponential factor causes the terms in A s and higher to be negligible for all but the shortest times. Hence [CA(l / 6L,t)-C A (5 / 6L,t)] is proportional to 1T 2 exp[L2 DAat] Thus the slope of a plot of the logarithm of that concentration difference against time yields DAB The unknown and unimportant A1 is includ ed in the intercept. Since a difference in vapour concentration is required, considerable error would result if the sample volumes were not identical. The purpose of the ethane tracer is to permit correction for differing sample volumes by use of: the areas of the ethane peaks from the 126 GLC. Note that calibration of the GLC is un necessary so long as peak area is proportional to the moles of species in the sample, since ace tone peak areas ( corrected using ethane peak areas) may be used in place of molar concentra tions in the difference term above: the intercept of the plot changes, but not its slope. The stagnant film experiment is Crosby's [8]. Here the film is arranged to be very thick-it occupies a diffusion cell about 0.4 m high. A pile of discs with a hole in each is assembled on a central pivot and can be arranged so that the holes are in line to form a vertical tube. At the bottom a reservoir carries a volatile liquid, e.g., acetone. At the top a cap has a stream of nitrogen flowing through it. It is assumed that the concentration of vapour at the bottom is due to the vapour pres sure at room temperature; at the top it is always zero. Starting with nitrogen only in the system, vapour is allowed access at zero time. At any sub sequent time, t, vapour will have diffused towards the top. At time, t, alternate discs are rotated to isolate each section of the cell. A stream of nitro gen is used to flush out each section in turn and a quantity proportional to the vapour mole frac tion is determined by a thermal conductivity cell (katharometer) attached to a chart recorder. The shape of the vapour concentration profile is thus established. The only important modification from Crosby's design is that 'O'-rings were recessed into the horizontal faces of the dural discs to seal them adequately. The mathematics is laid out in BSL [9]. In contrast to the 'long time' analysis above, the analysis here is for 'short' times so that there is no breakthrough of acetone into the top cell. Then a semi-infinite boundary condition is used (Z = oo, CA = 0), and solution is effected by Boltzmann's transformation or by Laplace trans form. The text is careful to draw attention to the error which could occur by naive application of Fick's second law. The measured value of diffu sion coefficient may be compared with that from the experiment above. ADIABATIC BATCH REACTOR An exothermic batch reaction is performed batchwise in a stirred Dewar flask, with progress followed by measurement of temperature, as de scribed by Williams [10]. However, in addition to the reactions he recommends (sodium thiosul fate with hydrogen peroxide, and acetic anhyCHEMICAL ENGINEERING EDUCATION

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dride hydrolysis), there is provision for study of the acid-catalysed hydrolysis of propylene oxide to the glycol [11 ] Assuming that this reaction is pseudo zero order in H 2 0, which is in great excess, and n t h order in propylene oxide, the heat and material balances yield the variation of tempera ture T with time t 1 dT = ( C 0 ) n-1 Aexp(-E / RT) (T r -T) n dt T rT o where subscripts f and O imply final and initial. For an assumed value of n, the values of the pre exponential factor, A, and the activation energy, E, may now be estimated either by (a) numeri cal / graphical differentiation of the measured T vs t curve followed by plotting the logarithm of the L.H.S. versus 1 / T [10] or (b) by a numerical integration method [11] in which experimental errors tend to be cancelled rather than amplified Both of these methods are readily programmed for the microcomputer which logs the T vs t curve (receiving a thermocouple signal ampli fied and digitised by a DVM). Also programmed is an ordinary differential equation ( o.d.e.) inte gration routine which permits integration of the o.d.e. above with the estimated values of A and E and the assumed value of n. Thus the student can plot the predicted T vs t profile to compare with the experimental values, and choose the value of n (from, say, 0, 1, 2) which gives the best fit. It is also possible then to predict profiles for different initial concentrations ( C 0 ) or tempera (T 0 ), and so to find initial values which will lead to very different predictions of the profile for different assumed values of n. A second experi ment allows easy discrimination of the best value of n [11]. A particular advantage of this reaction is that the order of reaction with respect to catalyst con centration, CH +> is easily found. From the o.d.e., writing A C H+m for A T 1 f dT (Tr T) 11 exp ( -E / RT) T o SUMME~ 1985 Consider two runs using different values of CH + but the same initial values C 0 T 0 and hence the same final temperature T r Choose some con venient intermediate temperature T 1 and note the corresponding values of t i for the two runs. Now, the LHS is the same for both runs. So (CH +m t i ) is constant too, so that the two pairs ( C H +> t 1 ) im mediately yield the value of m. As far as is known, this result is new. The values of n, m, E, A' obtained agree well with the literature [11, 12]. NOTES ON OTHER EXPERIMENTS The packed tower hydraulics experiment is a conventional study of loading and flooding in two six-inch diameter towers, one packed with Raschig rings and the other with glass helices. However, it has one pleasing feature: the first tower floods first at the top, followed by the flood ing moving downwards, whereas the second floods at the bottom and the flooded zone grows up wards. The cause of the former is presumably that the gas v olumetri c flow is highest at the top: of the latter, that the helices compress readily, so that the bed voidage is least at its base and resistance to flow is highest there. A remarkable number of students don't notice. The packed bed catalytic reactor is used to stud y the dehydration of 2-propanol to a mixture of propylene and di (2-propyl) ether over an alumina catalyst: this reaction is only mildly endothermic so that reactor isothermality may be assumed, the reactor and the feed preheater being in an oven. Catalyst particles are so small that pore diffusion limitations do not occur. The enzyme catalysis experiment is performed in a batch reactor made by modifying a spinning catalyst basket reactor of the Carberry type. Glucose is converted to fructose by an im mobilised enzyme "sweetzyme Q" manufactured by Nova A. S. of Copenhagen, used at 60 C and pH = 8.5. The constants in the Michaelis-Menten kinetic expression are determined. The rotational speed of the basket can be varied from run to run to permit investigation of external mass transfer effects. ACKNOWLEDGMENT This lab was assembled as a team effort, so Cnotinued on page 160 127

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(eJ ;j ?I curriculum BASIC INFORMATION SCIENCE TRAINING FOR CHEMICAL ENGINEERS* 0. M. KUT1, R. QUERALT2, AND L. M. ROSE 1 1 S w iss Federal Institute of Technology (E.T.H.) Zur i ch, Swit z erland. 2/nstituto Quimico de Sarria, Ba r celona, Spain. W ITH THE INCREASING amount of published in formation and improved methods of assessing this information, there is a new awareness within chemical engineering that systematic information retrieval from the literature is an important start ing point for any type of project. To match this awareness (already prevalent in industry), chemical engineering courses should include some instruction in the subject of information science. There is more to information retrieval than simply knowing where the library is and knowing how to use an index. It is possible to give students a more thorough background in information science in a comparatively short course-if it is well organised. The objective of this paper is to indicate the possible contents of such a course and to relate some experiences already gained in teach ing the subject to chemical engineering students. COURSE OUTLINE A modern information and documentation course for chemical engineers should cover print ed bibliographic information, numerical data, and methods of computer retrieval, both of numerical and bibliographic data. Available Printed Information Traditional literature searching has always concerned itself with searching the scientific journals-the primary publications. Since chemi cal engineering is a mixed discipline, it is often This paper was commissioned by the European Federa tion of Chemical Engineering, Working Party on In formation and Documentation 128 The objective of this paper is to indicate the possible contents of such a course and to relate some experiences already gained in teaching the subject to chemical engineering students. worthwhile to look in other specialized areas for relevant material-statistics, operations research, chemistry, mechanical engineering, computing, and electrical engineering all overlap with various chemical engineering subjects, particularly at the research level. Primary literature goes beyond the published journals; conference pre-prints, dissertations, and patents all belong to the primary literature, but are more difficult to obtain than the international journals. The difficulty in obtaining these very im portant publications is overcome by the develop ment of the secondary publications. The seconda r y publications are abstracts of the primary literature, the most famous of which is Ch e mi c al Abst r acts. Chemical Abst r acts is so important to the chemical engineer that he should be able to use it without difficulty understanding the concepts of its indexing and registry numbers for components. Chemical engineering has some lesser known abstracts of its own: Theoretical Chemical Engineering Abstra c ts (POB 146, Liver pool, England), Chemical Eng i nee ri ng Abstracts, (University, Nottingham, England), and DE CHEMA (PF 970 146, D-6 Frankfurt-97, W. Germany). Abstracts in overlapping fields (INSPEC for mathematics and control, Enginee r ing Inde x for heat exchange) can also be useful. Under secondary publications one can also list the S ci ence Citation Index (SCI) which enables forward searches to be made, and the ISi weekly publication of contents pages of the scientific journal, Current Contents, enabling the contents of most of the recent journal issues to be effectiveCopyri gh t C hE Di v ision AS EE 198 .5 CHEMICAL ENGINEERING EDUCATION

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ly followed. Finally there is the tertiary literature. This is an organised summary of the literature in each particular field: handbooks, monographs, data collections, and textbooks. Perry is, of course, the most important. Then there are the encyclo pedias of chemical technology of Kirk-Othmer and Ullmann. Numerical data are very important to the chemical engineer, and these are generally found in the tertiary publications. General data con cerning chemicals are best covered by Beilstein (organic) and Gmelin (inorganic). Though both these works were in German, new editions are now in English. Other publications concentrate on particular properties. Finally there are the monographs and text books. They often provide an excellent starting point for any search by summarizing the particu lar technology up to a certain point in time-which is often adequate for the needs of many problems. The graduating chemical engineering student should be aware of these facilities in his library. He should be able to carry out searches in Chemi cal Abstracts, know where to obtain numerical data, know how to use the subject and author catalogues in the library, and know that the li brarian is a trained professional, there to help him when he has difficulties. Computer Stored Informat i on Bibliographic Data Bases : The history of the development of computer readable bibliographic data bases is a fascinating opening to the subject Oemer M uhan Ku t received his M.Sc and Ph D degrees in chemical engineering from the Swiss Federal Institute of Technology (ETH) in Zurich Since 1972 he has been a re search associate at ETH His major research interests are in the areas of app l ied catalysis catalytic reaction engineering and modelling of multiphase reactors ( L ) Rafae l Qu era lt received h i s diploma in chemical engineer ing from IQS and since 1963 has been an assistant professor at the lnstituto Quimico d e Sarria He is also head of the Library and Documentation Services at IQS which is a pioneer ce n tre of automized chemical information in Spain ( C ) L. Murray R o se has a B.Sc. and a Ph.D i n chemical engineering SUMMER 1985 of the production of SDI (Selective Dissemination of Information) tapes. To rationalize the pro duction of the printed abstracts, the total ab stracts were coded onto magnetic tape. It was then a small step to the distribution of these tapes to institutions wishing to perform their own searches electronically rather than waiting for the printed versions to be posted and going through them manually! It is interesting for most chemical engineers to know the principles on which the computer searching is done. The availability of the ab stracts on tape, the need to have a thesaurus and to invert the SDI tapes to be able to recover which abstracts refer to each particular keyword are important points to explain in the course. There is a growing feeling among informa tion scientists that the engineer himself should under s tand ho w computer searches are done. The need to choose the individual keywords carefully and to define a suitable search strategy, to know the pitfalls of not including enough alternative descriptions, and to know ho w to improve the relevance by including further keywords. It is particularly important that the chemical engi neer know which data bases are likely to be of most use to him. Surveys in Europe have shown Ch e m ic al Abst r a c ts to be the most useful (al though it is far from ideal for most chemical engi neering problems). Ch e mical Abstracts needs backing up with COMPENDEX or INSPEC, where appropriate. Besides these three there are many other data bases covering particular areas of use to chemical engineers-part of the NIH EP A Chemical Information System for safety from Birmingham University Before joining the Systems Engineer ing Group of the Technica l Chemistry Laboratory of the Swiss Federal I nstitute of Technology (ETH) in 1 971, he spent twe l ve years in in dustry. His efforts are toward instigating the sensible use of com puters in all branches of chemical engineering. ( R ) 129

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and chemical properties, DERWENT for patents, PREDICAST for commercial information, DE CHEMA for equipment design and corrosion problems, etc. The undergraduates should be made aware of the scope and limitations of the various fields. It is also good for the undergraduates to be informed on the component parts of the computer literature searching system-the abstractors, the files and inverted files, the hosts, the communica tions networks-that all need paying for every character retrieved. And then, the multitude of languages! Numerical Data Banks: Parallel to computer retrieval of bibliographic data, banks of physical properties for use by chemical engineers have The subject would be given more status if it were a short course in its own right, and not simply squeezed into odd hours. been developing and are now generally accessible by any terminal connected to the telephone net work. Most normal chemicals in commerce (::::::800) are now available on these banks which store numerical physical property data, or use predictive methods to give estimated values for those not available. PPDS, EPIC and DECHEMA systems are available in Europe, and PPDS in the us. For teaching purposes, a number of small demonstration banks exist. CHEMCO is probably the most widespread. There is no better way of making a student realize that these modern tools are available to him than to let him use them during a design project. Such data banks could be handled in an in formation and documentation course or in a thermodynamics course, since they are excellent for demonstrating enthalpies, chemical equilib rium, vapour-liquid equilibria (VLE), and equa tions of state. For them to be handled in both courses would have the advantage of helping inte grate the whole curriculum. SEARCH PROCEDURES There are two fundamental types of litera ture searching Retrospective searching, where a comprehensive list of relevant literature published on a special topic is sought 130 Current awareness searching (SDI = Selective Dissemination of Information), where the interest concerns the current publications on the topic under study. The selection of information sources and the mode of information retrieval will depend on the type of search. For starting a systematic litera ture search, the problem and its limitations should be clearly defined. In manual as well as in on-line searches, the effectiveness of the study depends on how well-prepared the search strategy is. To get some experience in strategy preparation and optimization, the library users should practice manual searching techniques before starting on line searches. A very useful start for undergraduate students in chemical literature are small search exercises in Chemical Abstracts using the printed indexes. The user should become familiar with the Index Guide and the Chemical Substance Index using the Chemical Abstracts nomenclature. He should also learn the concept and the limitations of the Registry Numbers. These numbers, characteriz ing a single, well-defined chemical compound, build a link between different bibliographic and numerical data banks. The user should also prac tice how to select relevant keywords with all their synonyms and truncations. He should also be familiar with the linking concepts (and, or not) creating combinations of sets selected by the key words. For narrowing the search strategy the user should also be aware of other possible limi tations such as language, document type, country, or publication year. Even with all these preparations, electronic information retrieval continues to be a difficult task for the average user without the assistance of information specialists. For example, the Chemical Abstracts (CA) SEARCH files are ac cessible from many host systems such as Lock heed, SDC, or Data Star. However, every host system has its own software and its specific ad vantages and disadvantages, making different set combinations and search strategies possible. The fine structure of the programs are developing. An average end-user making only a limited number of on-line searches cannot be aware of all the pro gress made to reduce the search costs. Although development in the direction of "user-friendly systems" is progressing, at the moment the op timal combination seems to be co-operation be tween the information specialist who knows the information systems and the end-user who knows CHEMICAL ENGINEERING EDUCATION

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the extent of his information requirements, so that the on-line systems can be used efficiently as an interactive system adapting the search strategy to the given information. This need for teamwork between the information specialist and the engi neer is ground enough for the undergraduate engineer to be made aware of the principles of information retrieval. TEACHING EXPERIENCE Experience in the Swiss Federal Institute of Technology (E.T.H.) In common with many other universities, the time-table structure at E.T.H. makes it virtually impossible to introduce new courses, so modern methods of information and documentation have to be squeezed into two hours borrowed from an other course, with practical exercises carried out as part of a semester project. The introduction to the semester project enables an additional two lecture-hours on manual searching to be given. Because the particular semester project is con cerned with literature retrieval (four days), the students get ample practical experience on manual searching. The total of four lecture hours (which includes a computer search demonstration) is not really adequate to properly cover the material six to eight hours would be better. The four-day manual search project is more than necessary for the normal chemical engineering student. How ever in the Technical Chemistry Department at E.T.H. there is a strong emphasis on chemistry, which is consistent with e~tended information re trieval exercises. The subject would be given more status if it were a short course in its own right, and not simply squeezed into odd hours. This could con veniently be taught together with odd hours given on communication (report writing, specification writing, drawing standards, speaking and lectur ing) to provide sufficient material for an inde pendent course on communication. Undergraduates do not carry out computer searches, but postgraduates are allowed to carry out some of the searches by computer in collabora tion with an information specialist. Experience at the lnstituto Quimico de Sarria Since 1979 the Higher Technical Education Centre for the formation of engineers has pro vided a course on Scientific and Technical Docu mentation for the fifth-year students (the last SUMMER 1985 r,na conferences DESIGN CONFERENCE AT VPI The ChE Department at Virginia Tech wishes to invite ChE edu cators to attend the Frank Vilbrandt Memorial Conference on Chemical Process and Plant Design. The Conference is scheduled in celebration of the 50th anniversary of the founding of the ChE Department at Virginia Tech and will be held on October 10 and 11, 1985 Further information can be obtained from Y. A. Liu, ChE Dept., Virginia Tech, Blacksburg, VA 24061. year of the chemical engineering curriculum). It is compulsory for those students who opt for the research course, at the end of which a Trabajo de Fin de Carrera (final report on conclusion of studies) has to be submitted before the degree (in chemical engineering) can be awarded. It is, however, optional for those students who do not go for this research course and who will conse quently not complete their studies with this de gree. The course is run for one week with two hours every day, giving a total of ten hours for _the presentation of the various topics. The exercises are done on an individual basis outside the regu lar course time, which means an average extra time requirement of three hours for the practical exercises. In the presentation of the material, emphasis is put on practical application, the im portance of one-line systems demonstrated, and extensive use of visual material like slides and transparencies is made. The course contents are remarkably similar to Table 1, which is the pro posed curriculum we are recommending. The experience with this course during the last five years has been highly positive. The students have learned or improved their ability to handle basic documentary sources (like Chemi c al Abst r acts, Beilstein, Science Citation Index). They know the possible ways of using information media in their search for information, how to ac cess them, and finally, and this is very important, they realize the complexity of the process for searching for information and are aware of the assistance available from the specialist in in formation and documentation. COURSE CONTENTS The European Federation of Chemical Engi neering has had a Working Party on Information Continued on page 142 131

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tib a classroom IMPROVEMENTS IN THE TEACHING OF ST AGED OPERATIONS MARYAM GOLNARAGHI, PAULETTE CLANCY AND KEITH E. GUBBINS Co rne ll U n i ver sit y Itha ca, NY 14853 THE USE OF COMPUTER graphi c s to a id and improve the teaching of chemical engineering principles is an area of growing interest. Many topics have the potential to be greatly improved by utilizing the special capabilities of computer graphics, with rewards s uch as greater instructor efficiency and additional aid for educationally weaker students. One such topic is the teaching of staged operations, usually conducted within a separations course. For studies involving di s tilla tion-the single most important separation tech nique-the graphical method of McCabe and Thiele [1 ] is typically employed due to its con ceptually simple formulation. However the manual calculation of a single McCabe-Thiele plot for one case study is a lengthy and laborious procedure, as any junior will attest! In order to Maryam Golnaraghi is cur rently a Ph D cand i date in the Theoretical and Applied Me chanics Department of Cornell Univers i ty studying non equi librium properties of granular materials using statistical me chanics. She received her B S degree in Chemical Engineer ing at Cornell in 1984. (L) Paulette Clancy i s current ly an assistant professor in chemical engineering and as sociate director of the Manu facturing Program at Corne I I University. She received her BS degree at th e University of London and a D Phil. degree at the University of O x ford She h e ld fellowships at Cornell Univers i ty and at London University before j oining the facu l ty at Cornell in 1984 (Cl Keith E Gubb i ns is currently the Thomas R. Briggs Professor of Engineer i ng and dire c tor of chem i cal engineer i ng a t Cornell Uni versity. He received his BS and PhD degrees at the University of 132 investigate the effect of different design param eters on the resulting column, this time-consuming procedure must be repeated for each new case. The repetition involved is of limited educational value, yet it is most important that the student have a firm grasp of the inte r relationship be tween the various operating parameters, e.g., the reflux ratio and the condition of the feed. The usual result is that a severely restricted number of cases can be studied, with additional limita tions on the complexity of the system. The results of other interesting designs must be presented to the student already complete, dulling the sense of discovery that thei r investigation might have pro duced. Computer graphics offers solutions to these problems, removing the burden of compu tational effort while preserving the simple graphi cal representation which allows a ready compre hension of the situation. These advantages were recognized by Calo and Andres [2 ] However their McCabe-Thiele package was devised around the older technology of direct v iew storage tube graphics, which is unsuitable for interactive use. London, and was on the staff at the Univers i ty of Florida from 196276 when he moved to Cornell. He has held visiting appointments at Imper i al College London at Oxford University and at the University of California at Berkeley He has co-authored two books Applied Statistical Mechanics (Reed and Gubbins) and Theory of Molecular Liquids (Gray and Gubbins ). (R) Copyri gh t ChE D ivision, ASEE 1985 CHEMICAL ENGINEERING EDUCATION

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Computer graphics offers solutions to these problems, removing the burden of computational effort while preserving the simple graphical representation which allows a ready comprehension of the situation. In the graphics package developed at Cornell, the software was written for a sophisticated vector refresh graphics workstation offering su perior interactive capabilities with virtually im mediate response to user-interaction. This pack age was implemented in the fall semester of 1984, and will be used in our separations course. DESIGNING THE PROJECT: HARDWARE AND SORWARE The Computer Aided Design Instructional Facility at Cornell's Engineering School has been described in an earlier publication [3]. Of the graphics workstations available, a vector refresh Evans and Sutherland Multipicture System was chosen for this application since software ex pertise for this type of system was available with in the department. However, the nature of the application is such that it could equally well have been set up on a raster graphics system; indeed, the programs have been structured for such a change if necessary. User interaction with the package was made possible largely through the use of an electronic tablet and stylus (or pen), with a VTl00 terminal for alphanumeric input. An electrostatic plotter was available for 'hard copy' output of the contents of the screen, a use ful feature for the preparation of homework as signments. As with the graphics package to represent phase diagrams developed at Cornell [3 ] the ap pearance of this software package was carefully conceived so that the design criteria given below would be fulfilled in the most effective and invit ing fashion-in other words, in what computer scientists like to call a "top-down" approach. The objectives of the software package were For a complete set of user-supplied variables de scribing the system, a McCabe-Thiele plot should appear on the monitor's screen, together with a scaled diagram of the resulting distillation column. Interaction with the software package to change any of the design parameters should be easily effected and should produce an almost instantaneous response in recomputing the McCabe-Thiele plot and the design of the column, redisplaying them on the monitor. This interaction should be designed so that qualitative trends in column design resultSUMMER 1985 ing from parameter changes could be viewed almost continuously if desired, or that specific values for these parameters could be entered if a quantitative calculation is required. Extensive help must be available to aid the con fused, while the ability to restore the original screen display is essential for the computationally en tangled. Instructive messages should appear on the screen to inform the user of the program's status for example, if some unavoidable delay in process ing the input is about to occur. The program must be structured in such a way that its extension to more complex problems can be incorporated into the existing software in a straight. forward manner. Thus some long-range planning of the possible modifications to the package had to be considered. As far as; possible the software produced should be portable, so thought had to be given to pro ducing a machine-independent code. The decision to write the software in FORTRAN, still the most widely used high-level language in engineering, stemmed from this desire. Last, but still important, the programs should be "bomb-proof," even for the most inventive student user! The most likely input errors, or miskeying, must be anticipated wherever possible. Should these objectives not be met, resulting in a final product that was difficult or frustrating to use, much of its educational impact would be lost. Such attention to detail in designing the ap plication graphics package is extremely time-con suming in terms of software development, but the effort is amply recompensed once its use is es tablished as a regular component of the course. THE INTERACTIVE McCABE-THIELE PACKAGE We believe that the final product does indeed meet the criteria given above, satisfying both the instructor s and the student's differing needs. It is a routine matter to produce numerical sub routines performing the calculations for the Mc Cabe-Thiele plots, but more time-consuming to incorporate the graphics software to display an aesthetically pleasing picture on the screen and an ergonomically attractive interaction with the displayed image. The layout for the display is as shown in Fig. 1. The master object displayed consists of a Mc Cabe-Thiele plot with appropriate equilibrium and operating lines and the "ladder'' of stages. 133

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This is supplemented by a scale diagram of the corresponding design for the distillation column (relative to a six-foot tall 'stick figure' standing beside it). Above these diagrams information about the current values of the various operating parameters is displayed, while the space b~low is reserved for the "menu." The menu provides a selection of options to enable the user to interact with the viewed image. The user may select a par ticular option by moving the pen across and slight ly above the tablet until the cursor (in the form of crosshairs on the screen) lies within the re quired area (or window) designated for this option. Pressing the tip of the pen down in con tact with the tablet activates the window to per form a specific task. The menu options for interacting with the package are listed below ( the window names are in bold face type) 1. Six windows allow input of both the com position and the ftowrate of the feed, distillate, and waste product. The program will prompt the user for values of any four independent variables from these six in order to completely define the prob lem. Values are entered by placing the pen down at some point within the window. Each window contains a potentiometer which allows the value of the appropriate variable to decrease or increase as the pen is moved left or right across the window. The value given by the current position of the pen may be read in the area above the diagrams. 2. When the calculate window is selected, the program checks to see if the mass balance was satisfied by the user-supplied variables. If the mass balance was not satisfied the user is in formed and will be prompted to re enter all four values. In this way the programs assure that the student is capable of performing the mass balance correctly. Assuming all is well, a McCabe-Thiele plot is produced for "start-up" values of the operating parameters, e.g. the reflux ratio. 3. The user may now alter these operating parameters by selecting appropriate windows for the reflux ratio, operating pressure and heat per mole of feed. Again, moving the pen along the length of the window alters their respective values with immediate response from the pro grams, producing altered images for the McCabe Thiele plot and column design. 4. If the user desires to set an exact value for any variable this can be done using the ke y in option. This offers an alternative to using the po134 --~--~;i~7--~l~lrn ~ rmiftoflhr) l(D) OO fi ~r1hng Prn1PJr1{ATII) 1.00 011hlht1 50J.CIJ ld 10 R.t!1,1:1 R1ho 3.106 &tton, 5(1).00 SYSTEM BENZENE( 1 )_HEPTENE(2) Feed Rate Feed Compos l t l on Otstt I !ate Rate Bottoms Rate Bottoms Compos, t ,on FIGURE 1 tentiometers within the windows, which are more suited to observing qualitative trends in the behavior of the McCabe-Thiele plot. The 'key in' feature prompts for numerical input at the VTl00 terminal. 5. The reset window sets all the flowrates and compositions to zero and the operating paramet ers (p, R and q) back to their initial preset values. 6. The window marked economical analysis allows the user to determine the optimum value of the reflux ratio in cost effectiveness. This will be explained in more detail in the following section. 7. Snap triggers the production of a paper copy of the current screen contents on a nearby plotter. 8. Help invokes the display of information pertinent to the operation of each of the windows in turn. 9. Exit halts execution of the program. COLUMN DESIGN The McCabe-Thiele method is widely used as an educational tool in teaching distillation column design at the undergraduate level, and details of the method need not be repeated here. In the existing version of the program, a single column involving only one feed of a binary mixture of components is considered. Extension of the pro grams to multiple feeds and sidestreams is under way. The feed may be introduced into the column CHEMICAL ENGINEERING EDUCATION

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in any fluid condition (i.e., saturated liquid, sub cooled liquid, etc). Antoine's equation is used to obtain the saturated temperatures and pressures of both components, and the x-y equilibrium curve is obtained assuming ideal behavior. Op tional consideration of a variety of non-ideal de scriptions of the equilibrium curve is also possible. Routines are included which calculate the di ameter and height of the distillation column for each case study in order to produce the scaled diagram described earlier, including the correct number of bubble-cap trays, a total condenser, reboiler, and the location of the feed tray. This is achieved by following the recipe outlined in Treybal [4]. Some interesting aspects of column design with regard to the economics involved are also in corporated by allowing the preparation of a graph showing the relationship between a given reflux ratio and the total cost involved, considering both capital costs and estimated running costs over the expected lifetime of the column. The minimum of this parabolic curve allows the estimation of an optimum reflux ratio for the most cost-effec tive operation of the column. SUMMARY The implementation of the computer graphics package described has proved to be of consider able assistance in the teaching of staged opera tions. Instructors benefit from the increased quantity and complexity of problems which can be investigated in the alloted time, and students welcome this novel and easy-to-use tool which makes completing their assignments so much less onerous. ACKNOWLEDGMENTS M. G. would like to thank C. D. Naik and G. Charos for many helpful discussions. It is a plea sure to thank the Gas Research Institute for practical support of this work. REFERENCES 1. McCabe and Thiele, Ind. Eng. Chem., 17, 605 (1925). 2. J. M. Calo and R. P. Andres, Comp. in Chem. Eng. 5, 197 (1981). 3. C. D. Naik, P. Clancy and K. E. Gubbins, Chem. Eng. Ed., 19, 78, (1985). 4. R. E. Treybal, Mass Transfer Operations, 2nd edition (1968), McGraw-Hill, NY, p. 131-135, 142-144 SUMMER 1985 (ejijplll letters More on Tubular Flow Reactors Dear Editor: Professor Asfour's two improvements ( GEE XIX, 2, 84, 1985) to the original design of a tubu lar flow reactor using crystal violet dye and sodium hydroxide reactants (Hudgins and Cayrol, GEE XV, 1, 26, 1981) are timely ones This ex periment, to judge from a recent survey (E. 0. Eisen, "Teaching of Undergraduate Reactor De sign," AIChE Meeting, San Francisco, Nov. 1984), is now incorporated into several reaction engineering laboratory courses in North America. I welcome the occasion of the Asfour article to suggest several additional improvements that arise out of our experience since 1981. First, I concur with the footnote in the Asfour paper. Tygon tubing is an unhappy choice for the tubular reactor. In our experience, clear Tygon tubing darkens within a few hours' use to a per manent deep violet. This obscures the pleasing axial color change that is one of the main at tractions of the experiment. Polyethylene tubing, though translucent rather than transparent, re sists the crystal violet dye for a much longer time. Calculating the reactor volume can be a prob lem. Certainly, the nominal value of the inside diameter of the tubing is not sufficiently accurate. Some students have improved on this value by trying to fit the tubing using indexed drill bits. Because of the flexibility of the tubing, however, it is not certain that the cross-sectional area re mains undistorted when the tubing is wound on the large spool. Weighing the spool with the re actor tubing empty and then filled with water ap pears to be the most rigorous way to obtain the volume. In both of the above GEE articles, the spool is shown mounted on its side. This has proven to be an unfortunate method of mounting since bubbles often enter the reactor tubing (perhaps from the mixer pump) become trapped in the coils of the tubing, and grow. An effective remedy is to remount the spool with axis perpendicular to the lab bench and flow spiralling upward. Of course, this does not eliminate bubbles but does prevent their retention and growth sometimes to several percent of the total reactor volume. Continued on page 161. 13{>

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(eJ ;j I laboratory RECYCLE WITH HEATING A Laboratory Experiment A FOORD AND G. MASON Loughborough University of Technolog y Loughborough, Leicestershi re, England s OME OF THE BASIC methods of chemical engineering (heat and mass balances, for example) have analogies (such as money) in everyday life and freshman students rarely have any con ceptual difficulty when such basic ideas are intro duced. However, when heat and mass balances are combined with recycle, students often have difficulty in analysing the process. They have diffi culty not so much with the heat and mass balances themselves as with the whole concept of the re cycle process. This is mainly because there is no immediate everyday counterpart, although anTony Foord received his BSc and PhD degrees in chemical engi neering at the University of Birmingham (England) and was sub sequently employed in research and development by the U K Atomic Anergy Authority and by the Distillers Company in London in process development and project evaluation In 1966 he joined the faculty at the Loughborough University of Technology His teaching interests have been process economics and chemical engineering calculations and his principal responsibility has been the ov era ll management and development of the undergraduat e courses (L) Geoff Mason graduated in chemistry at the University of Bristol in 1962 He then worked for h i s PhD in the physics department at the University of Bath before returning to Bri stol as a research fellow In 1970 he joined the faculty at Loughborough where, apart from a year spe nt at the Petroleum Recovery Research Center (New Mexico) he has been ever since His research i nte rests are mainly concerned with the capillary properties of porous materials, particularly pore blocking and network effects (R) 136 In order to aid the understanding of recycle we have devised a simple apparatus in which water is heated in a recycle loop alogies can be attempted with taxis and people. In order to aid the understanding of recycle we have devised a simple apparatus in which water is heated in a recycle loop. When operated in the steady state, the apparatus permits both a visual and an experimental appreciation of the operation of a simple recycle loop. Moreover, in the unsteady state the apparatus has a response time of ten minutes or so, and thus, transient be haviour can be followed easily. The apparatus is relatively simple, and since it is built from do mestic plumbing pipes and fittings it has a familiar and easily grasped appearance. It is mounted on a wallboard so that the flow path can be seen at once. It uses only water and electricity as consumables APPARATUS Fig. 1 is a schematic diagram of the appara tus. The recycle is driven by a domestic central heating pump of the type used to circulate water around radiators Ours is an SMC Commodore and it consumes about 150 watts. The heater is a modified instantaneous shower heater in essence a copper can containing a 3kW heating element. The shower heater originally had two in-built safety devices, one a water pressure switch and the other an anti-scald thermal cut-out. The heater could only be activated when there was pressure (and hence water) in the can and the tempera ture was below 50 We modified our heater to increase the cut-out temperature to 80 C and re moved a flow constriction in the pressure-sensing circuit. The pump drives the recycle at up to 8 litres / Copyrig ht C hE DiviBion, ASEE, 1985 CHEMICAL ENGINEERING EDUCATION

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Q+q t t Q q H e c t er ( H kW) Pu m p t Q Q Qo 7j To RECYCLE W or m Cold water w a t e r i n ou1 FIGURE I Schematic diagram of the apparatus. The inlet flow, Q (maximum 3 litres / min), is ordinary mains water A recycle loop, flow q (maximum 8 litres / min) is driven by a pump through a do mestic shower heater (3kW). The temperature of the inlet water, the outlet water and just after the heater in the recycle loop, are all measured. min, the highest reading of the recycle rotameter. There is a rotameter (3 litres / min maximum) on the inlet side measuring the inlet flow of tap water and an identical one on the outlet side. Mercury-in-glass thermometers (although digital devices would be better) are used to measure the water inlet temperature, the temperature after the heater in the recycle loop and the outlet temperature. The water flow rate of the feed and also of the recycle loop may be adjusted and set by means of valves. The complete rig is il lustrated in Fig. 2. The tube sizes, although apparently arbitrary, make a difference to the performance of the ap paratus. Air comes out of solution in the heater and tends to accumulate in the pump which is working here at less than its design flow. By using 28 mm tubing at a slightly rising angle for the top tube of the recycle loop and 22 mm tube for the descending tube to the pump, the air tends to enter the outlet pipe rather than be carried down wards. In the 15 mm sections air bubbles are easily carried along, either upwards or down wards. EXPERIMENTS Steady-State Mass balan c es: The first experiment is trivial but is a graphic illustration of the mass balance principle: at various valve settings it is easy to show that whatever the recycle rate the inlet flow rate always equals the outlet flow rate. Heat balances: a) With the heater switched SUMMER 1985 on and at a fixed input water flow rate, the apparatus shows that the outlet water temperature is independent of the recycle rate. Students often find this observation disconcerting. They observe a change in the temperature of the recycle water when its flow rate is altered, but find that the outlet temperature of the loop remains the same. Only when they consider the overall heat balance do they find it obvious that the outlet temperature is unaffected. b) Using the variables marked on Fig. 1 for flows and temperatures for the steady-state, a heat balance over the whole system shows that T 1 = T o + (H / QC) (1) where H is the combined heat input of the pump and heater and C is the specific heat capacity of water. Similarly one obtains T 2 = T 0 + (H / QC) + (H / qC) (2) from a heat balance across the shower heater after eliminating T 1 by means of Eq. (1). So, by measuring the outlet water tempera ture, Ti, as a function of the through flow rate, Q, it is possible to determine the combined heat input of the heater and pump by the use of Eq. ( 1) The experiment takes some time to perform because it takes about fifteen minutes for the steady-state to be reached after a change in flow rate. By plotting (T 1 T 0 ) against 1 / Q, the gra dient (H / C) gives the power input (H) as shown on Fig. 3. Alternatively, Eq. (2) can be used. In FIGURE 2. A photograph of the apparatus It is mounted on a wall board so that the flow directions are obvious. The top pipe is slightly angled to assist in purging the air which comes out of solution as the water is heated. 137

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60 50 f--0 I 40 f-_., E 20 a. E 1 0 Grad i ent = 45 9 d egree li tres / m i n Heater p o wer = ';;5 0 9 X 4 2 0 --"""T"-----.----.-----0 0 2 0.4 0 6 0 8 1.0 I. I 1 /0 min / 1 FIGURE 3. Results from the steady-state operation of the apparatus The temperature rise of the through stream is plotted against the reciprocal of the through flow rate The graph is a straight line through the origin with a gradient determined by the combined energy input of the heater and circulating pump. this case T 2 is plotted against 1 / q, where q is the recycle rate, and H is obtained from the same gradient. This latter method has the advantage of actually making use of the recycle flow. Unsteady-State In unsteady-state experiments both the inlet flow and recycle flow are fixed, the system is al lowed to approach, but not necessarily reach, equi librium, and the heater is switched either on or off as appropriate. The apparatus takes several minutes to respond and the dynamic changes can be monitored by hand. Typical examples of temperature-time graphs are shown in Fig. 4 for both rising and falling temperature. The recycle rate was 5 litres / min and the inlet flow rates 1.0, 1.5, 2.0, 2.5, and 3.0 litres / min. A heat balance on the system for a small time interval, dt, in which the outlet temperature, T, changes by dT gives QCT o + H = QCT + VC (dT / dt) (3) where Vis the volume of the recycle circuit which, as an approximation, is assumed to be perfectly mixed. Using Eq (1) to eliminate H, and then integrating from T 0 at time 0, gives ln [(T 1 T) / (T 1 T 0 ) ] = -Qt / V (4) T thus rises exponentially to the steady-state temperature T 1 when the heater is switched on 138 60 50 4 0 30 20 10 5 0 .... .3 ~20 10 0 Throu ;h flo w I I/ m in RE CYCL E RA T E 5 I/ m in 1 00 100 -----1.5 I/min ---2 Vmin ~ ---=-= -=-=2 5 V m i n ---3 I/ m i n He a ter switched o n at time .. 0 200 300 4 00 500 ti m e I, secs FIGURE 4(a) R E CYCL E RATE 5 1 / min Heate r s w i tched o ft ot time O 1.5 I/ m i n 200 3 00 tim e, I secs 2 I m i n ---2 s 1/mi n 400 FIGURE 4(b) 500 600 600 Figure 4. Results from the unsteady-state operation of the apparatus The recycle rate was fixed at 5 litres / min and the response is only slightly dependent upon it. Fig 4(a) shows the effect of switching the heater on at different through flow rates. Fig. 4(b) shows the effect of switching the heater off at different flow rates. The temperature rises in Fig 4(a) and falls in Fig 4(b) exponentially to the limiting temperature. The different limiting temperatures in Fig. 4(b) are caused by the heat input from the recirculating pump and also by small changes in the feed water temperature Note that the re sponse time is a function of the inlet flow rate and falls exponentially to the temperature T 0 when the heater is s w itched off. The time constant is independent of the heater power and also of the recycle rate but depends on Q, the inlet flow rate, and the volume of the system. By plotting the log arithmetic term of Eq. ( 4) against time, the gradient (-Q / V) can be determined. If this is repeated for several flows then a graph of these gradients against Q gives a straight line of slope 1 / V through the origin. The volume of the recycle circuit so deter mined is only an effective volume rather than a C HEMICAL ENGINEERING EDUCATION

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-I [r, r ] 7j-To -2 3 t i me r secs 100 2 00 30 0 4 00 500 FIGURE 5. Logarithmic plots of the results of Fig 4(a). 0 -0. 3 n[lj-Tl 7i-Ta J 0 6 0.9 O I li t res / m in 2 He a t i ng C o ol ing Gradient = I / V = 0.2 4 0 V = 4 17 lit r e s e q uiv a lent 6 00 FIGURE 6. The effective volume of the recycle system determined from the gradients of the lines in Fig 5 by plotting the gradient against the through flow rate. Values from the curves of Fig. 4(b) are also shown although the straight line logarithmic plots have not been reproduced. true internal volume because the metalwork of the system behaves as a heat sink. Its effect is quite large because the pump weighs several pounds but conduction is fast enough for the metal and fluid in the recycle loop to have the same temperature. The temperature profiles of Fig. 4 demonstrate that, as predicted by Eq. ( 4), the system reaches equilibrium faster for higher inlet flow rates than it does for lower inlet flow rates. Figure 5 shows the straight lines given by Eq. (4) for r ising temperature using the typical data gi v en in Fig. 4. Note that there is a delay of be tween 10 and twenty seconds before the ther mometer responds to the heater being switched on, due to the transit time of the water in the pipes. Fig. 6 shows the gradients of the lines of Fig. 5 plotted against Q, the inlet flow rate, and it is from the gradient of Fig. 6 that the effective v olume V, of the recycle loop can be determined. SUMMER 1985 4) en ;: 4) :, C '4) C. E 4) I3 Gradient= 3 00 degree litres/ min / Heat input = 3 6 ~ 0 x 4 2 = 0 21 I I 0 5 1 0 I /o min/litre FIGURE 7. The temperature rise of water passing through the system obtained from the limiting temperatures of the cooling curves (Fig, 4(b)) and the feed temperature plotted against the reciprocal of the through flow rate This graph is equivalent to the steady state results of Fig 3 but with the only heat input coming from the energy of the pump. The slight offset of the line from the origin is most likely caused by a systematic error between the two separate thermometers which were used to measure the temperature rise REFINEMENTS The analysis of the behaviour of this appara tus is straightforward. The accurate interpreta tion of actual experimental results is not so simple because of drift in the temperature of the water feed and other small effects. Rough and ready results and analysis may be adequate for routine teaching, but to get the best from the apparatus a more refined approach is necessary. For example it is better to extrapolate the dynamic experi mental data to obtain the steady-state tempera tures. This gives students useful practice in analys ing an exponential rise to a limit as well as giving the steady-state temperatures more accurately. The falling temperature curves give limiting temperatures which, because of the heat input from the recycle pump, are not equal to the inlet w ater temperature T o Indeed the temperature rise between the inlet water temperature and the extrapolated outlet water temperature with the heater switched off can be used in a heat balance to determine the energy input by the pump. Fig. 7 shows liT, the temperature rise of water through Continued on page 143. 139

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[j;j#I class and home problems The object of this column is to enhance our readers' collection of interesting and novel problems in Chemical Engineering. Problems of the type that can be used to moti va te the student by presenting a particular principle in class or in a new light or that can be assigned as a novel home problem are re quested as well as those that are more traditional in nature that elucidate difficult concepts. Please sub mit them to Professor H. Scott Fogler ChE Department, University of Michigan, Ann Arbor, MI 48109. ONE MONTH PROBLEM ... An Exercise in Modelling V. RA VICHANDRAN Indian Institute of Technology Kanpur-208016, India IN APPLIED MATHEMATICS courses the emphasis is usually on solving equations. There is very limited discussion about problem-definition and expressing it in terms of mathematically under stood phenomena. A mathematically understood phenomenon is one which, at least in its simplest form, can be expressed mathematically [1]. Once the problem is interpreted, it requires only the substitution of symbols for words before a rele vant equation is obtained. Teaching this missing part of the story is difficult because it is a crea tive process. There are no set procedures avail able for such an exercise. The students can, at V Ravichandran is an assistant professor at the Indian Inst itute of Technology, Kanpur, India Pr ior to coming to Kanpur he was a visiting assistant professor at the University of Notre Dame where he obtained his PhD (1981) He received his BTech in ChE from the University of Madras (1977) and MS from Oklahoma State University (1978) His research interests include a variety of topics including chemistry of catalysis, biochemical engineering mathematical modelling, and application of microprocessor to chemical engineering 140 best, be helped to learn by themselves. With this in view, in a course entitled "Applied Mathematics in Chemical Engineering," the students are given a 'one month problem.' The problem is a real life situation which has to be defined in such a way that it can be expressed and analyzed mathematically. The students are encouraged not to get into complicated mathematical formulations. This strategy helps the students to concentrate and to appreciate the subtle nuances involved in prob lem definition and modelling strategies. Thus the scope of the 'one month problem' is limited and should not be confused with the regular modelling exercises. Wherever possible, the simple model obtained is evaluated against the existing data. Near the end of the semester the problems are assigned to the students (one each) as a project, to solve as regular modelling problems. One such problem is discussed below. PROBLEM You are going to spend the winter in the middle of nowhere, say in the Himalayas or in Alaska, where the temperature gets very cold. You are going to stay in a cabin where there is no heating. How will you decide whether the sleeping bag you have will keep you warm enough or comfortable? Solution The best way to find out is to ask somebody who has experienced the same climate. In the ab sence of an experienced person, however, we have Copyright ChE Di v ision, ASEE, 1985 CHEMICAL ENGINEERING EDUCATION

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to resort to mathematical modelling to determine how much insulation is necessary to keep the body warm and comfortable. Before we proceed with th~ solution, the term "comfort" has to be defined in the context of the problem. "Comfort" depends largely on the skin temperature. When the skin temperature is high, sweating begins and the latent heat of evaporation cools the body down. It is very uncomfortable when one starts sweating inside the sleeping bag. Hence the temperature at which sweating begins marks the upper limit of the "comfortable" skin temperature, which is 34.5 C [2 ] The skin temperature begins to fall when the skin is exposed to cold temperature. The self-de fense mechanisms of the human body try to main tain the skin temperature ; ho w eve r the com pensatory measures fail below 32 C, w hich is known as the shivering temperature [2 ] As long as the skin temperature is between the sweating temperature and the shivering temperature the person feels comfortable, i.e., T s w > T s > T s h where T sw the sweating temperature T s = the skin temperature T sh the shivering temperature From the above discussion the problem can be redefined as follows : At a given outside temperature, calculate the insulation necessary to maintain the body temperature between shivering and sweating temperatures. The follo w ing assumptions are necessary to make the problem mathematically tractable T h e heat production rate is at q kcal / m 2 hr and the skin temperature is uniform throughout. The loss of heat by convection, radiation, and evaporation is negligible, and the heat is lost only by co n duction. The air pocket between the s leeping bag and the body is neglected. Let us assume the body is rectangular in cros s ~ og ( a ) SUMMER1985 Insulation L Ta j_ 1/////ff Tt FI GUR E 1 B o dy Ts ( b) section, and a sleeping bag of thickness t is cover ing it uniformly as shown in Fig. 1 (a). Since the skin temperature is uniform throughout, a simple one-dimensional model is sufficient to describe the system, as shown in Fig. 1 (b). Under steady state conditions the rate at which heat is pro 4 E lJ 3 .. 1/) 1/) c,, C -"' 2 lJ (JI 0 ID 1 -30 Ts:32C k: 0 0315k col/ hr C q:35kcollm 2 hr -20 -10 0 10 Surrounding t<2mp<2rotur<2 To, C FIGURE 2 20 duced should equal the rate of heat conducted through the sleeping bag. Thus dT q = K p A dx and the integrated form is t = K p ( T T n ) = ( : p ) T a + ( K~T s ) ( l) where A 1 T n surrounding temperature t thickness of the sleeping bag K P thermal conductivity of the packing material For a given outside temperature and the thermal conductivity of the insulator, the re quired thickness of the sleeping bag can be com puted using Eq. (1) Fig. 2 shows the relationship between the sur rounding temperature and the bag thickness for a man whose average basal metabolic rate is 40 kcal / m 2 hr [2]. In the absence of any other in formation, the thermal conductivity of the bag is assumed to be the same as that of animal wool, i.e. 0 0315 kcal / mhrC [3]. It is very obvious that this model fails closer to the ambient tempera141

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TABLE 1 Average basal metabolic rate for males and females of various ages [2] Kcal / hrm 2 AGE MALE FEMALE 10 45.0 43.0 20 39.0 35.0 30 37.0 35.0 40 36.5 35.0 50 35.5 34.0 ture because of 'no air pocket' assumption. It can be easily shown that the required thick ness does not change with various age groups as the heat production rate is not significantly differ ent (Table 1). In cases where the ground tempera ture is cooler than the atmospheric temperature, we can make a conservative estimate of the bag thickness by taking both the ground temperature itself as the surrounding temperature and the thermal conductivity of the compressed packing material. It was found that the assumption of cylindri cal shape for the body does not alter the result significantly. ACKNOWLEDGMENT Contributions of Umesh K. Jayaswal, Atul Bansal, and V. L. N Murthy are gratefully acknowledged. REFERENCES 1. Ravichandran, V., "Ch e micall y Processed Mathe matics to be published. 2. Bell, George H., J. N. Davidson and D. E. Smith, T ex tbook of Phy si ology and B i och e mi s try, 8th Ed. 1972. 3. Foust, A., L. A. Wenzel, C. W. Clump, L. Maus, and L. B. Anderson, Princ i ple s of U nit Op e rat i on s, 2nd Ed., 1980. INFORMATION TRAINING Continued from page 131. and Documentation in existence for a number of years, with the objective of assisting the intro duction of new methods into the chemical engi neering profession. As part of this work they have developed a suggested curriculum for a course in information and documentation for chemical engineers. This is given as Table 1. This table could be taken as the basis for any new course de veloped for chemical engineers. CONCLUSIONS The aim of this paper has not been to give a 142 quick course on information and documentation, but simply to mention the trends in this quickly moving area and to indicate that there is sufficient material relevant to a chemical engineer to form a short course on the subject If the reader is left confused, but impressed, then we have achieved our aim and suggest he get together with his own information scientist (librarian) to develop a course for his undergraduates We believe a course of about nine to twelve hours would be ideal. This would enable about three hours of exercises in the library to be made and a computer retrieval demonstration to be at tended. If this amount of time is not available, then two hours of lectures could survey the material and practical experience could be gained TABLE 1 Proposed Curriculum for Basic Information Science Training SOURCES OF INFORMATION Printed a) Primary Sources: Journals and reports, con ference reprints patents, dissertations. b) Secondary Sources: Chemical, Chemical Engi neering and Engineering Abstracts; SCI. c) Tertiary Sources: Handbooks, encyclopedia, books. Advances in List important ones. Computer Data Bases a) Bibliographic data base s b) Numerical data bank s SEARCH PROCEDURES a) Manual: Indexing, Search Techniques; Biblio graphic, Data. b) Computer Searching: Bibliographic: files, networks, host computer; data base selection; searching techniques; costs Numeric Data Banks: available banks; procedure cost c) The role of libraries and information scientist s in association with laboratory work and project work. At least, practical experience should be planned and guided-not simply left as a random search for the student to undertake when all else has failed. ACKNOWLEDGMENTS The authors wish to express their thanks to those members of the E.F.C.E. Working Party on Information and Documentation who comment ed on the draft outlines of this paper. Their com ments were gratefully received and incorporated CHEMICAL ENGINEERING EDUCATION

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into the final text. REFERENCES Baltatu, M. E., "On-Line Information," Chem. Eng. (NY), p. 69 (1984). Fidel, R., D. Sorgel, "Factors Affecting On-Line Biblio graphic Retrieval: A Conceptual Framework for Re search," J. Am. Soc. Inform. Sci. 34 (3), pp. 163-180 (1983). Fries, J. R., "Data Base Searching in Chemical Engi neering," Chem. Eng. (NY) 88 (26) p. 71 (1981). Graham, M. H., A. B. Lamy, B. Lawrence, and L. Y. Stroumtsos, "Information Retrieval," in Kirk-Othmer, 3rd. ed., 13, pp. 278-336, ( 1981). Hall, J. L., M. J. Brown, "On-Line Bibliographic Data Bases." An International Directory, 2nd. ed., Aslib, London (1981). Henry, W. M., J. A. Leigh, L. A. Tedd, and P. W. Williams, On-Line Searching: An Introduction, Butterworths, London (1980). Kaback, S. M., "On-Line Patent Searching: The Realities," Online 7 (4), pp. 22-31 (1983). Rasmussen, P., "Data Banks for Chemical Engineers," Danmarks Tekniske H0jskole, Lyngby, Denmark (1980). Rose, L. M., "U ebersicht iiber die gegenwartig ver fiigbaren Datenbanken fiir physikalische Eigen schaften," CHI MIA 33, p. 256 (1979). Stanley, W. G., "Unique Information Resources for the Chemical Engineer," Chem. Eng. Prog. 77 (6), pp. 8082 (1981). RECYCLE WITH HEATING Continued from page 139. the apparatus, plotted against 1 / Q. The energy in put of the pump is found from the gradient to be about 210 watts. The intercept (about 0.3C) probably represents the scale reading difference between the two thermometers. A further refinement that is possible with the apparatus is to run the dynamic experiment in the limiting case of recycle with no through-flow. With no through-flow the apparatus is analogous to a well-mixed batch reactor, whereas it is an alogous to a CSTR when through-flow is present. Fig. 8 shows results for this case for three differ ent recycle rates. The three lines do not coincide because different starting temperatures were used. The results show that after 30 seconds or so there is, as expected, a linear temperature rise with time. The temperature rises with no limit at least until the safety cut-out of the shower heater operates. The gradients of the lines on Fig. 8 are all the same and by using the combined heater and pump energy input of 3.21 kW it is possible to estimate the effective recycle volume. SUMMER 1985 This is 3.95 litres for the results shown, about 5% less than the value obtained using the through flow method. The most likely cause is the time taken to heat up parts of the metalwork of the pump; this experiment lasts only four minutes, compared to ten for the through-flow method. Students always say that the apparatus could be improved by lagging the pipework to reduce heat losses, but simple measurements on a cool ing curve indicate that the heat losses are very small. Also, for some of the temperature response 80 70 60 (.) 50 40 ::, 0 30 a. E 20 10 0 0 Re c ycle Rate 3 litres/min 5 litres /min 7 litres /min .. 100 en e rgy input is 3.21 kW then 3.21 tne e ff e ctive volume is 4 2 x 0 1 9 3 200 Time secs = 3 95 litres 300 FIGURE 8 With n o through fl o w the recycle l oo p temperat u re rises with o ut limit as can be seen a b ove. Usi n g the c o mbined ene r gy inp u t of the heater and pu m p (determined on Fig. 3) the effecti v e v o lume of the recycle loop can be determined using the gradient of t h e lines. This volume can be compared with the value determi n ed on Fig. 6 (4.17 litres equivalent). The lines are for different recycle rates which, as expected, have no effect. Different initial temperatures were used. Up to the first minute it can be seen that the system is not well.mixed. curves the water temperature is below the am bient air temperature and so the system is gain ing heat rather than losing it. CONCLUSION Our apparatus has been in service for several years without giving trouble, perhaps a conse quence of using well proven domestic components. The recycle experiments performed with it can range from simple mass and heat balances right through to the dynamics. Its main purpose, how ever, is to provide a vivid demonstration of basic mass and heat balances in a system with re cycle. 143

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IMPACT OF PACKAGED SOFTWARE FOR PROCESS CONTROL ON CHEMICAL ENGINEERING EDUCATION & RESEARCH BRIAN BUXTON Teesside Polytechnic Middlesbrough, United Kingdom J N AUGUST 1982 THE Department of Chemical Engineering, Teesside Polytechnic, UK, took delivery of a Ferranti Argus 700GL process control computer system. The system was supplied in accordance with a detailed enquiry specification which defined precisely the objectives and scope of the system (Table 1). The objectives of the system are To assist departmental research into varied chemi cal engineering topics by providing a compre hensive and flexible data logging and plant control system To provide a teaching facility for the department The availability of packaged software transforms this situation, enabling the engineer (student or practitioner) to produce useful process control software in a matter of days rather than months. by live demonstrations of plant monitoring and control applications, simulation, and implementation by students of control strategies It is now timely to report on the extent to which these objectives have been realised. At the time this paper is being written, the system is capable of controlling two pilot plants and has also been substantially integrated into our teach ing programmes. Computer control is now taught TABLE 1 Enquiry Specification 1. Objectives and scope of the system 2. Extent of supply 3. Exclusions from supply 4. Functional specification Data acquisition Data logging Pilot plant control Operator interface Data links Development facilities Teaching facilities 5. System hardware configuration Configuration Equipment specification Control system description Maintenance facilities Availability / reliability 6. Supply of software Standard systems software Standard packaged application software Special to project software for a) plant control b) data links High level language Operator facilities Management / engineer facilities Failure / recovery Expansion capability 7. General electrical & electronic design requirements Equipment housing Power supplies Cable schedules Environmental requirements Safety requirements Expansion capability 8. Acceptance tests System hardware / software Packaged software Application software System robustness System loading 9. Installation and commissioning requirements 10. Documentation 11. Project time schedule 12. Maintenance and training requirements 13. Project management Project organisation Project communications and control 14. Commercial requirements Co p yright ChE D iviBi on, ASEE, 19 85 144 CHEMICAL ENGINEERING EDUCATION

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Brian Buxton is a senior lecturer in the Department of Chemical Engineering, Teesside Polytechnic, UK. He studied at the University of Aston in Birmingham receiving his BSc degree in 1967 and his PhD in 1971. He spent 10 years in industry with both ICI and the British Steel Corporation. During this period, he was responsible for the specification, installation and commissioning of several com puter control systems He joined Teesside Polytechnic in 1981 and was responsible for the specification and procurement of the Ferranti Argus computer control system featured in this article. His research interests include the implement atio n of adaptive control techniques on chemical processes. in all the higher education courses offered by the department Higher Diploma BEng Honours Degree Course s Post Graduate Degree Courses (MSc and PhD) as well as providing a key facility for our post graduate research teams. It is emphasized that all the teaching pro grammes involve a substantial proportion of practic;:il experience on the computer system coupled with live demonstrations of on-line com puter control. It has been found that this new approach to teaching process control stimulates considerable interest from the students who are readily able to relate to these practical situations. Furthermore, the experience gained on such SIMUIJITION l'AtU ;LS / \ 0 cJQCJ "' / MO NOC H JIOHEVDU'n () HO RELOCATEO N U TO l' ILO T PIJitmlJ I \ 00 'N INCARTRlOCf.lllS <: STORAGr. SYSTEl'I PROCE:SSOR HEMORY .\ND PERIPll!:IIAL \ VUIS / DJ E \ I PIJiNTINPllT /OIJ TFUT f'.(lllIPMENT FIGURE 1. Computer System Configuration. systems is much more directly applicable to the industrial environment than the classical control theory or the modern control theory commonly taught in higher education courses. The configuration of the computer system is illustrated in Fig. 1 and defined in Table 2. Sufficient industrial interface equipment has been purchased to enable the system to control several pilot plants simultaneously. It also provides con nection to simulation equipment. The simulation equipment facilitates both teach ing and testing of research software. The mono chrome VDU's may be sited alongside pilot plants to provide local operator display and control facili ties. Software development may also take place at these locations if required. Further colour graphics terminals will be added to the configura tion in the future. The pilot plants are accommodated in three module rooms. These rooms extend from the ground to the top floor of the building and can acTABLE 2 EQUIPMENT Argus 700 GL processor Semiconductor stores (256 Kb) Monitor and control console Peripherals Monochrome VDU's (15 inch display heads and keyboards) 20 inch colour monitor and functional keyboarli Matrix printers (180 cps) Keyboard for printer Plus drive cards for all peripheral de vices and serial input / output cards SUMMER 1985 Computer System Configuration QUANTITY 1 2 1 5 1 2 1 for data links Storage Media Twin cartridge disc storage system (10 Mb) (one exchangeable, one fixed) Twin floppy disc storage system (1.0 Mb) Industrial Interface Equipment Analogue inputs Analogue outputs Digital inputs Digital output s Pulsed digital outputs Plus usual power supplies, fans, pack aging, etc. 1 1 176 72 64 64 8 145

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commodate large column type processes. A pair of reactor bays is also provided on each floor of the building. Multicore cables have been laid to link the computer to pilot plants in all of the above locations. CONTROL PACKAGES The standard system software P.M.S. (Pro cess Management System) encompasses all the facilities required to implement, operate, and manage a computer controlled process. Software packages have been provided by the computer manufacturer which greatly assist the engineer in building the application software required to operate his particular plant. It is this facility which enables the teaching of the subject within the time scale and context of a higher education course. Prior to the availability of control packages, the general approach of computer system suppli ers was to provide "tailor made" software for a specific application in the form of a so-called "turn key" contract. The software was written in Ferranti computer control system. a real-time high level language such as CORAL. This meant that engineers were either required to learn in depth a high level language and the as sociated operating system of the host computer system, or to define their system requirements to a programmer, who in turn implemented the re quired functions in software. Either of these op tions was time consuming, costly, and therefore inefficient. The time scale required to learn such programming skills can be measured in months, rather than weeks, of dedicated work, which makes it impossible for it to be incorporated as part of a higher education course. 146 The task of the engineer is then to select which operations are needed for a specific case and to link them together accordingly. The availability of packaged software trans forms this situation, enabling the engineer (student or practitioner) to produce useful pro cess control software in a matter of days rather than months. Specifically, the packages assist the engineer in implementing the following functions in soft ware Interfacing of plant signals to and from the computer Continuous control Sequence control Operator interface: a means of display and modi fication of process and control information. All are clearly essential for the commission ing of any computer control system. The packages are based on the principle that certain operations are common to all process control applications, while the order in which they are applied is spe cific to the particular application in question. The task of the engineer is then to select which operations are needed for a specific case and to link them together accordingly. The pack age provides considerable assistance with this linking "construction" by providing a conversa tional facility for the engineer in the form of displayed messages (prompts). The task is then reduced from one of detailed programming to one of deciding on a control strategy and then de fining a series of operations and associated parameters to implement the strategy. Thus, vir tually no programming skills are required and the problem of programming errors which normally arise in the programming of complex software is largely avoided. TEACHING PROGRAMS In the context of control packages the teach ing of control system design, from initial strategy to implementation and testing of software using hardware and software simulators, is entirely practicable. Every opportunity has been taken to incorpor ate our computer control facilities in our teaching programmes. These include Laboratory Practicals for the Higher Diploma C HEMICAL ENGINEERING EDUCATION

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students: e.g., interfacing of plant measurements. This requires that the student generate the software to condition and convert electrical signals into engineering units. The operation of the software is then tested by means of simulation panels. Short Course (10h) for the final year of the BEng course. The course includes several practical sessions on building software to interface signals, continu ous control loops, and operator displays. The pro ject used to assess the students in the current academic year requires that the students work as a project team to generate the entire software to monitor, data log, and control a fermenter. The facilities will include sequence control of the plant and a colour graphic display of the process pro viding a live mimic of the plant operation. This is no artificial project since the software produced by the undergraduates will ultimately be used by the department's biotechnology research team to imple ment computer control on a newly acquired fer menter. Mention should also be made of the allocation of a limited number of research projects to second year degree students which involve the computer control of laboratory scale apparatus. Current projects involve the control of pH and level. Chemical engineering also offers service teach ing to other Polytechnic departments. The op portunity has, therefore, been taken to off er com puter control of a pilot plant as a case study. This academic year, students from both the Com puter Science Department (Information Tech nology MSc Course) and the Department of Electrical, Instrumentation and Control (BSc2) have received a concentrated study on computer control of a specific pilot plant. Like the other courses offered, the courses include a substantial proportion of practical experience on the com puter system and live computer control demon strations. POST GRADUATE RESEARCH With regard to research, the main thrust has been directed toward the commissioning of direct digital control of a gas absorption column. This work involved the use of adaptive control (the self tuning regulator) which has been used to optimise the operation of a cascade loop on the column. This research is reported in a separate paper [l] and will not be considered further here. However, it is worth noting that the speed with which this research was implemented owes a great deal to the availability of packaged software on the system. While the self tuning regulators were in fact programmed in a high level language, the interfacing of this software with the control SUMMER 1985 packages ( which are responsible for all other control facilities) was straightforward and rapidly achieved. It should be noted that apart from this one specialized application, all our soft ware requirements to date have been easily imple mented by the control packages. Future research effort will be directed to the Graphics display of gas absorption column pilot plant. implementation of computer control on a novel catalytic reactor which has been developed within the department over a number of years [2]. The control system will facilitate prolonged operation al runs and assist in further research into com mercial application and scale up of this unique reactor. The plan is to apply the adaptive control techniques (recently proven on the gas absorption column) to this reactor. This process lends itself particularly well to these techniques in view of its time varying nature due to the decaying catalyst. This is the main target for the research team. In conclusion, it is clearly important to recog nise the potential of packaged software in the teaching and research environment. (There are also considerable implications for the industrial applications, but that is beyond the scope of this paper.) Packages are rapidly gaining recognition as vital tools for the modern chemical engineer. In an environment of continuously falling com puter hardware costs, coupled with the ever-rising costs of producing "tailor made" software, it is essential that the engineer makes full use of com mercially available packages. The cost of plant de sign, implementation and operation of chemical processes and their associated automation systems can be considerably reduced by judicious use of Continued on page 161. 147

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ti Na classroom ESTIMATION OF FLUID PROPERTIES AND PHASE EQUILIBRIA M. HERSKOWITZ Ben-Gurion Uni ver s ity of the Negev Beer-Sheva, Israel NUMERICAL VALUES OF physical, thermodynamic and transport properties of pure compounds and mixtures are necessary for the development of chemical processes and the design of chemical plants. Experimental data available in the litera ture are limited but the need for the estimation of such properties is crucial in calculations carried out by chemical engineers. The study of correla tions for estimating various properties is an inte gral part of courses in transport phenomena and thermodynamics. Considering the importance of the subject, a course designed to cover the theoretical and practi cal aspects of properties estimation was intro duced into the curriculum. The course is given to junior and senior students who have a strong back ground in thermodynamics and transport phe nomena. Throughout the course, two fundamental methods for estimating properties are emphasized Correspo nding states principle (CSP) Equations of state (EOS) Another method is the group contribution method. This approach is used for estimating thermodynamic properties of ideal gases (no intermolecular forces) and also for estimating critical points of pure compounds [1] and activity coefficients in the liquid phase [7]. The outline of the course is listed in Table 1. Since this field is very dynamic, the outline is up dated every year according to new developments. All correlations and samples of calculation are organized in a manual distributed to the students. During the lectures the theoretical basis of the correlations is discussed and the advantages and disadvantages of various correlations are pointed out. In the first lecture the students receive a list of primary, secondary, and tertiary literature sources which are useful during the course. The Cop11rioht ChE Di 11 i8ia11, ASEE, 1985 148 M. Herskowitz comp l e t e d his PhD in chemical engineering at the University of California Dav is, i n 1978 and since 1979 has been a faculty member at the Ben Gurion Un iversity of the Negev, Beer Sheva, Israel. His principal interests are multiphase re actor de si gn synthetic fuels, and estimation of thermodynamic properties In 1984-85 he is spending a sabbatical with E xx on Research and Engi neering Co. and at the University of Delaware as a visiting professor. book of Reid et al [ l ] is recommended as an excel lent reference to correlations published until 1976 Other books [2, 3, 4] are used as references to the theoretical basis in properties estimation. The proceedings of the International Conference on Phase Equilibria and Fluid Properties [5, 6] are also valuable references. The students are en couraged to read original papers in order to gain some insight into the limitations of the various correlations. The material studied during the course is practiced in homework problems which include ap plications of the correlations. For this purpose computer programs are available in topics such as Phase equilibria calculations by the UNIFAC method Phase equilibria calculations by EOS Calculation of critical point s of mixtures Some of the programs were provided by Ras mussen [8]. The students are also required to w ork on a project. Each student selects a certain property and prepares a report which includes A literature search that covers a period of the last three years, based mainl y on Chemical Abstracts CHEMICAL ENGINEERING EDUCATION

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but also on current journals. Selection of two papers dealing with general cor relations, a summary of the basic approach, and the conclusions. Selection of a limited database from the literature for testing the correlations. Only primary sources are used with proper estimation of the experimental accuracy of the data. A comparison of the correlations and practical con clusions. Working on this project, the students gain ex perience in the literature search, the understand ing of correlations, and their proper applications. TABLE 1 Course Outline* INTRODUCTION: 5 Lectures ** a. Corresponding states principle (CSP): theoretical background (2, 9 ] b. Classification of fluids: simple, normal, polar and quantum [9] c. Critical points of pure compounds: Lydersen (1], Ambrose (10 ] d. Equations of state (EOS) (11]: cubic EOS, the virial EOS, mixing rules e. Critical and pseudocritical properties of mixtures, mixing rules PHYSICAL AND THERMODYNAMICAL PROPERTIES: 18 Lectures a. Molar volume of gases and liquids 1) CSP: Lee-Kesler [12], Teja et al [13]; COS TALD [14], Gunn-Yamada (1] for liquids 2) EOS: Redlich-K wong ( 1 ] Soave-Redlich-K wong [1], Peng-Robinson (15 ] 3) Virial EOS: Tsonopoulus (1], Hayden-O'Connell [16 ] Orbey-Vera (19] b. Enthalpy, entropy, fugacity, and heat capacity 1) CSP: Lee-Kesler (12 ] Tyagi (20] 2) EOS: RK [1 ] SRK [1 ] PR (15] 3) Construction of diagrams such as the Mollier diagram c. Vapor pressure and heat of vaporization: Lee-Kesler [ 12], Riedel [1], Vetere (17] d. Thermodynamic properties of ideal gases: Thinh Trong [18 ] for hydrocarbon, Benson [1] PHASE EQUILIBRIA-VLE, LLE, SLE, GAS SOLUBILITY: 9 Lectures a. Theoretical background (2, 3] b. EOS [3 ] : SRK [1], PR [15 ] c. Group Contribution Methods: UNIFAC method (7] TRANSPORT PROPERTIES: 10 Lectures a. Theoretical background [ 4 ] b. Viscosity: Reichenberg [1], Ely-Hanley [21] c. Thermal conductivity: Ely-Hanley (22], Euken [1], Roy-Thodos [1], Robbins-Kingrea [1] d. Diffusion coefficients: Wilke-Chang [1], Scheibe} [1] Only part of the references are listed. ** Each lecture lasts 50 minutes SUMMER 1985 This is also an opportunity to test the reliability of experimental data. Some projects have yielded interesting results which stimulated further re search. The course is a good opportunity to review and emphasize the practical aspects of fundamental principles in thermodynamics and transport phe nomena. Five classes of students have already com pleted this course. They found it useful in practical courses such as plants design, unit operations lab, and the senior project. Furthermore, it provides some of the tools a practicing chemical engineer needs. D REFERENCES 1. Reid, R. C., J. M. Prausnitz and T. K. Sherwood, The Properties of Gase s and Liquids, McGraw Hill, 3rd Ed., N.Y. (1977). 2. Prausnitz, J. M., Molecular Thermodynamics of Fluid Pha s e Equilibria, Prentice-Hall, Englewood Cliffs, N.J. (1969) 3. Van Ness, H. C. and M. M. Abbot, Classical Thermody namic s of Nonelectrolyte Solutions McGraw-Hill, N.Y. (1982). 4. Hirschfelder, J. 0., C. F. Curtiss and R. B. Bird, Molecular Theory of Gases and Liquids, J. Wiley, N.Y. (1954). 5. Sandler, S. I. and T. S. Storvick, eds., "Phase Equilib ria and Fluid Properties in the Chemical Industry," ACS Symp. Ser. 60, Washington (1977). 6. Renon, H., ed., "Fluid Properties and Phase Equi libria for Chemical Process Design", Fluid Phas e Equilibria, 13, 14 (Special ed.) (1983). 7. Fredenslund, A., J. Gmehling and P. Rasmussen, Vapor-Liquid Equilibria Using UNIFAC, Elsevier, Amsterdam (1977). 8. Rasmussen, P., Private communication (June 1983). 9. Leland, T. W. and P. S. Chappelear, Ind. Eng. Chem., 60 (7), 15 (1968). 10. Ambrose, D., NPL Reports 92 and 98, NPL, Teddington (1979). 11. Abbott, M. M., Adv. Ch e m. Ser. 182, 47 (1979). 12. Lee, B. I. and M. G. Kessler, AIChE J., 21, 510 (1975). 13. Teja, A. S., S. I. Sandler and N. C. Patel, Chem. Eng. J. 21, 21 (1981). 14. Hankinson, R. W. and G. H. Thomson, AIChE J., 2 5, 653 (1979). 15. Peng, D. Y. and D. B. Robinson, Ind. Eng. Chem. Fund., 15, 59 (1976). 16. Hayden, J. G. and J. P. O'Connell, Ind. Eng. Chem. Proc. Des. Dev., 14, 209 (1975). 17. Vetere, A., Chem. Eng. J., 17,157 (1979). 18. Thinh, T. P. and T. K. Trong, Can J. Chem. Eng., 54, 344 (1976). 19. Orbey, H. and J. H. Vera, AIChE J., 29, 107 (1983). 20. Tyagi, K. P., Ind. Eng. Chem. Proc. Des. Dev., 14, 484 (1975). 21. Ely, J. F. and H.J. M. Hanley, Ind. Eng. Chem. Fund., 20, 323 (1981). 22. Ely, J. F. and H. J. M. Hanley, Ind. Eng. Chem. Fund., 22 90 (1983). 149

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laboratory AN INNOVATIVE CHE PROCESS LABORATORY SKIP ROCHEFORT, STANLEY MIDDLEMAN AND PAO C CHAU University of California San Diego La Jolla, CA 92093 THE CHEMICAL ENGINEERING Program has recently been introduced into the Department of Applied Mechanics and Engineering Sciences (AMES) at the University of California, San Diego (UCSD). The first courses in chemical engi neering were offered in the fall of 1979. The strategy was to integrate the new discipline into the previously existing engineering curriculum (fluid mechanics, thermodynamics, engineering mathematics, etc ) while gradually introducing traditional chemical engineering courses. A genuine chemical engineering program was achieved in the fall of 1982. Initially targeted as one of the major priori ties was the establishment of a chemical engineer ing undergraduate unit operations laboratory to be given at the senior level. We also determined at an early stage that we should develop the in novative skills of the students and not follow the Skip Rochefort received his BS from the University of Massachusetts his MS from Northwestern University and is currently working toward his PhD at the University of California, San Diego He also worked at the AT&T Bell Research Labs after receiving his MS (R) Stanley Middleman earned his baccalaureate and doctoral degrees at The Johns Hopkins University and was a professor of chemical engi neering at the University of Massachusetts before coming to the typical cookbook recipe formats so prevalent in many chemical engineering departments. During the past four years, the laboratory has evolved as a setting in which our seniors refine the classroom skills they have acquired and attack problems under circumstances similar to industrial ex perience. Under space, faculty, and financial re straints typical of many academic programs, we have developed what we feel is a unique approach. The Chemical Engineering Process Laboratory is taught at the senior level over two quarters, and has proven to be successful for a class size under forty, with the involvement of two faculty mem bers and a teaching assistant PHILOSOPHY Our main goal is to provide an environment in which the students have a large degree of control over the direction of their work. Students are skilled at following instructions and obtaining solutions to well-posed problems, situations which are not likely to occur in industry. We would like them to develop the ability to formulate a problem in process analysis and design design and perform University of California San Diego His major research interests are in the areas of fluid dynamics especially rheology and polymer pro cessing. (Cl Pao Chau is an assistant professor at the University of California San Diego He received his BS from the University of Delaware and his PhD from Princeton University. (L) C o p yright ChE D ivisi on, A SEE, 19 85 150 CHEMICAL ENGINEERING EDUCATION

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experiments to elucidate the problem, analyse the data and present pertinent results in a concise form, and draw conclusions in support of recom mendations of further action. STRUCTURE The structure of each lab group is similar to that of an industrial process research and develop ment group, with a project head (faculty advisor), group leader and group members, and technical support staff. A fairly general problem statement is presented by the project head and the students are instructed to arrive at the "best solution" to the problem given constraints in funds, equipment, and time (ten weeks). An example of a typical problem statement is shown in Fig 1. (Blax / Beech, Inc. is a pun on Black's Beach, a local nude beach and prime surf spot.) The students are expected to outline an experi mental approach to the problem, design and build the necessary experimental apparatus, perform appropriate experiments, and analyze the data. The design and construction process includes se lection of material, pumps, valves, fittings, etc., and interaction with the technical support staff who do most of the machining. The lab group also has to select appropriate analytical and measuring devices (e.g., gas chromatograph, viscometer, pH meter, thermocouples, etc ), as well as proper data acquisition procedures (e.g., IBM PC with A / D card, multichannel DVM, strip chart recorder, etc.). Once they have selected a device, the students are expected to learn from instruction manuals provided by the manufacturers, and to perform all necessary calibrations. No exceptions are made with the more expensive equipment such as gas chromatographs, a Brookfield viscometer, or IBM personal computers. The technical staff is avail able for consultation but only intervenes when procedures undertaken by students may endanger the equipment or themselves. During the planning phase the students are encouraged to contact local industry for ideas, and to consult equipment manufacturers and field representatives when necessary. They are also urged to examine and keep abreast of the current research literature in their problem area over the project duration. During the second quarter of the laboratory, they are encouraged to apply what they have learned in computer-aided design and process design courses to the modeling and design of their experiments. SUMMER 1985 During the past four years, the laboratory has evolved as a setting in which our seniors refine the classroom skills they have acquired and attack problems under circumstances similar to industrial experience. Blax / Beech Inc. Design Consultants to the Chemical Process Industries La Jolla, California Dat e: January 10 1985 To : CVD Reactor Group From : St a nle y M i ddleman Director Re : Ma ss Transfer in a CVD Reactor Chemical Vapor Deposition {CVD) is a heterogeneou s reaction process by which various chemical specie s may be deposited as very thin films on silicon wafers In the manufacture of semicondu c tor materials, CVD reactors provide a means of contact of a gas mixture with a set of wafers One problem in design of such reactors lies in the fact that mass transfer may affect the depo s ition rate and that the rate of mass transfer may not be spatially uniform in a CVD rea c t o r You are to design an experimental system with which you can explore factors that affect the rate and degree of uniformity of m ass transfer in a CVD reactor. Beginning January 17, and each week thereafter 1 expect to receive a typed progress report We shall also have a weekl y meeting at which time your group will make a twelve minute oral presentat i on to the class on progress and plans for future work A final presentation is to be g i ven during the week of March 13 and a final report is to be in my hands on March 19 Please do not hesitate to contact me if you need any technical or administra tive help in facilitating your progress FIGURE 1. Problem statement to CVD lab group. Strong emphasis is given to oral and written communication skills. Each week the group meets with the project head to discuss the project and present a written progress report. Project goals may be modified if justified by preliminary experi mental results or other extenuating circumstances. The group also has to give weekly oral presenta tions to the entire class. COURSE ORGANIZATION Students work in groups of three or four. After receiving their problem statement, they have two weeks to research the problem area, check out the available resources, consult with the project head, specify the goal and postulate the strategy to solve the problem. The project head mainly serves to provide insights as to whether the proposed pro ject is feasible, trivial, or too ambitious for a ten week period. The next four weeks are spent either in con151

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struction of new equipment or in modification of an existing apparatus, in performing preliminary experiments and in making further equipment modifications as required. Students are required to eubmit a mock purchase order for supplies and a job order requesting the assistance of the techni cal staff in building equipment. To avoid time lag the lab has to stockpile common items such as rotameters, glassware, valves and fittings Pre liminary experiments usually entail equipment calibration, determination of necessary thermo dynamic and physical properties data, solution preparation, and at least several trial runs of the experiment The main purpose of these prelimin ary experiments is to allow the students to become familiar and comfortable with the new equipment and to develop clean and efficient techniques. In the process they also learn the importance of careChemical Process Laboratory Oral Presentation Evaluation Speaker: Lab Group: Date: Category Poor Good 1. Presence 1 2 3 4 5 (Posture, Voice, Eye contact, Delivery) 2. Visual Aids 1 2 3 4 5 (Effectiveness, Clarity) 3. Length of Talk 1 2 3 4 5 4. Audience Contact 1 2 3 4 5 (Audience stimulation, Response to questions) 5. General Organization 1 2 3 4 5 (Introduction, Body Summary, Clarity) 6. Technical Content 1 2 3 4 5 (Was any work done? Data presentation and analysis) 7. Overall Effectiveness 1 2 3 4 5 8. If you were this person's boss, would you give him / her a raise? Would you continue funding for the project? 9. Co mments: FIGURE 2. Oral presentation evaluation form. 152 ful planning of experiments and the validity of Murphy's Law in experimental research. The remainder of the ten-week quarter is used to perform final experiments, analyze data, and prepare final oral and written reports. During the course of the quarter, the groups are required to submit a weekly progress report (five to ei~ht pages). The grading of the report is broken down into technical content and style. Ex tremely strong emphasis is given to proper writing style at the beginning of the first quarter. As the writing improves, the grading emphasis moves more toward technical content, much like a refereed journal article might be critiqued. The group leader, who rotates every week, has to edit the report and do the rewriting if requested. Be cause report revisions are often requested, word processing of the reports is encouraged, using the CA TT system on VAX or WordStar on the IBM PC. Over two quarters and including the final re ports, each student should have participated in writing sixteen reports. For the weekly oral report, students are re quired to give a twelveto fifteen-minute presenta tion in which the use of visual aids (either trans parencies or slides) is mandatory. The presenta tions are critiqued immediately after each session by the instructor for the benefit of all. Evaluation forms (Fig. 2) from classmates are passed on to the speaker after the instructor has reviewed them. Students sometimes find that the harshest com ments come from their peers. We schedule two separate oral presentation sections per week, each under the supervision of one of the instructors assigned to the laboratory. Lab groups are rotated in a staggered fashion through these sessions over the quarter. Thus each student faces a different audience for each talk. Moreover, the entire class is exposed to all the different experiments being conducted in the lab. LIST OF EXPERIMENTAL PROJECTS We have listed in Table 1 the experimental projects that were carried out during the 1984-85 academic year (2 quarters; 20 weeks). The ob jectives listed are a synopsis of the general prob lem statement which was presented to each lab group at the start of the project. Several of these experiments are interrelated and provide an opportunity for productive com munication between groups. The gas-lift reactor experiment permits examination of gas-liquid CHEMICAL ENGINEERING EDUCATION

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mass transfer in a reactor uniquely designed for the algae growth experiment. The effects of sparg er design, bubble size, gas flow rate, and solution electrolyte content on oxygen mass transfer are examined, with special attention given to their role in algae growth. The aerated stirred-tank experiment keys on mixing and oxygen mass transfer problems in microbial exopolysaccharide production, which is of interest to a local company (Kelco). Through pre-arrangement on the part of the instructors, specific members of the technical staff of Kelco are available to meet with students and provide con sultation. In the gas absorption experiment, in-line static mixers are used to study carbon dioxide absorp tion into a dilute sodium hydroxide solution in a cocurrent pipe flow configuration, as might be applied to an industrial "gas sweetening" pre treatment process. The system was donated by Komax, which is interested in obtaining perform ance data for its Komax Mixers in this type of ap plication. Engineers at Chevron Oil Field Research (COFR) in nearby LaHabra first stimulated our interest in the use of dilute polymer solutions in enhanced oil recovery. Using information they pro vided, the students were able to set up an experi mental study of the effects of polymer configura tion in dilute solution on the removal of oil from packed beds. Cylindrical and two-dimensional planar beds with various bead and sand packings have been used. Typical oil recovery polymers, supplied by Kelco and Do w Chemical Co., have been used in both pure water and brine solutions. A variety of experiments have been conducted over the past several years, ranging from single "oil blob" movement in a bed with a monolayer of uniform glass bead packing, to bulk oil dis placement from a cylindrical sand packed bed. Parameters of interest are polymer concentration necessary for oil displacement, polymer degrada tion and adsorption in the packed beds, and the effect of salts on these results. The chemical vapor deposition (CVD) experi ment required the design of a model of an in dustrial CV D reactor for the purpose of studying mass transfer effects on the vapor deposition pro cess. The development of this experiment was greatly influenced by contacts with researchers in TABLE 1 Experimental Projects in 1983-84 PROJECT 1. Mass Transfer in CVD: To stu dy the role of mass transfer in chemical vapoi d eposition processes. 2. Enhanced Oil Recovery / Porous Media Flow: To stu dy efficiency of polymers in enhance d oil re covery To look into effects of rheology, polymer degradation and adsorption. Flow visu ali z ation of oil "blob" movement in porous bed 3. Mass Transfer in gas-lift Reactor: Th e analysis of oxygen mass trans/ er in f ermenta tion systems. Effect of e l ec trolytes and fl u id proper ties on bubble dynamic s Reactor and spar ger de sign 4. Aerated Stirred Tank Mixing: Th e study of mixing and ga s-liqui d mass transfer in an aerated stirre d tank with non-Newtonian fluids. Th e application of novel impeller geometrie s. 5. Gas Absorption: To obtain design data for a cocurrent pipe /low gas absorb er using in -lin e st atic mixers. 6. Heterogeneous Catalytic Reactor: Kinetics of heterogenous catalytic reactions. To assess mass and h eat trans/ er effects in catalytic CO oxidation and methanation reactors 7. High Fructose Syrup Production: The study of immobilized enzyme kinetics, enzymatic reactor d esi gn, and ion-exchange column operation in the production of high fructos e corn syrup. SUMMER 1985 8 Mixing in Chemical Reactors: To stu dy the e ff ect of non-ideal mixing in the per ormance of tubular and stirre d-tank reactors 9. Ethanol Fermentation: Ethanol production in batch and continuous fer mentation F ermentation kinetics and bioreactor d e sign 10. A lgae Growth: Th e use of algae in bioma ss production. Eff ect of mass transport and bubbl e dynamic s on the kinetics of algae growth. 11. Hollow Fiber Membrane Separation: To stu dy the d esign problems of hollow fiber separa tion of bioma ss in application to microbial systems 12. Distillation: Batch and continuous azeotropic distillation prob lems wit h an isopropano l j water mixture. 13. Liquid-Liquid Extraction: Th e mass transport phenomena and d esign of a liquid-liquid ext raction column with soy b ean oil as the organic phase. 14. Plate Heat Exchanger: To d esi gn, construct and operate a plate heat ex changer system for use with viscous gelatin s ol u tions. 15. Wetted Wall Colu mn: Study of gas-liquid mass trans/ e r in falling films of viscous fluids and in the presence of surface active agents. 153

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the local semiconductor industry who were drawn to UCSD, in part, through the spring quarter Chemical Engineering Seminar Series, which was developed with the theme "Applications of Chemi cal Engineering in Semiconductor Technology." An experimental system was built in which naphthalene in a nitrogen carrier gas was de posited on the surface of an acrylic disc. The elimination of chemical reaction from the process served to isolate the mass transfer phenomena. In the catalytic reactor set-up we have pro visions for either CO oxidation or methanation re actions in either packed-bed, recycle, or single pellet reactor configurations. All recording equip ment, including thermocouples and the gas chroma tograph, are interfaced to an IBM PC. A BET ap paratus is also available for surface area and chemisorption experiments. The combination of all these options allows for a variety of interesting experiments for the students to plan and design. A biochemical application of the principles of kinetics and reactor design is investigated in the high fructose corn syrup production experiment. This experiment was implemented with the help of information supplied by Staley Co., using im mobilized enzymes and ion-exchange resins donat ed by Novo and Dow Chemical Co., respectively. The goal of the project is to look at more rational reactor and process design procedures. Computer modeling of the reaction / deactivation kinetics is also included. Classical chemical engineering kinetics and re actor design experiments are conducted by study ing mixing in stirred-tanks and tubular reactors. Mixing, as well as mixing with chemical reaction, has been studied in any number of reactor geometries-batch, stirred-tanks in series, tubu lar flow with static mixers or packed-beds, and any combination of these. Residence time distribu tions are studied with colored dye tracer and a spectrophotometer with a flow-through cell. Along with some of the previously mentioned experiments which have a biochemical twist to them, we have a series of experiments which are more directly oriented towards biochemical engi neering. Ethanol production is carried out by fer mentation using both single and multiple substrate growth media. The extensive cell growth, substrate utilization, and ethanol production data are com pared to data generated using classical biochemi cal kinetic rate models in computer simulations. The algae growth experiment was initiated due to the interest of a group of scientists at 154 We also have a lab which allows our students to get acquainted with new industrial developments, such as microelectronic fabrication and biotechnology, and with the integration of new technology ... into laboratory experiments. Scripps Institute of Oceanography. They have studied the optimum biological growth conditions (i.e., pH, light, growth medium, and temperature), while our engineering students concentrated their efforts on the role of mass transport in algae growth. As mentioned previously, we have de signed a two-dimensional, gas-lift reactor in which both algae growth and mass transfer experiments are conducted. The two-dimensional geometry is useful for flow visualization experiments to deter mine bubble dynamics and mixing in the reactor. The goal is the optimization of algae growth with respect to mass transfer limitations, while keep ing biological parameters constant. We have used hollow fiber modules donated by Asahi Medical Co. to conduct simple membrane separation experiments. The goal is to examine a process technology for concentrating cell mass in either cell recycle or biomass production processes. We do have some conventional chemical engi neering unit operations experiments in the lab. In the distillation experiment, the students have had to design their own plumbing and control schemes to convert a three inch diameter, six stage batch bubble cap column to continuous operation. The column feed is a cleaning solution provided by the university glassblower (a 35 / 65 % isopropanol / water mixture with some minor impurities). Ex tractive distillation techniques (e.g. the addition of a salt into the column) has been applied to pro duce an isopropanol / water distillate of 85-90 % purity. The students must also generate their own thermodynamic data. A gas chromatograph is used for data analysis and computer simulations of the distillation column are also conducted. The liquid-liquid extraction experiment uses soybean oil as the organic phase, mainly due to cost and safety reasons, but also because of the novelty of the process. The operation of the column for such a viscous continuous phase is quite differ ent from conventional extraction processes. The students must design experiments to examine transport phenomena in the column (e.g. droplet coalescence and break-up) and they must deter mine solubility data before they can design and conduct the extraction experiment. CHEMICAL ENGINEERING EDUCATION

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The plate heat exchanger experiment was initi ated and financed through a contract received from Eastman Kodak Co. The interest of Kodak is in the use of a plate heat exchanger to heat and cool photographic gelatin solutions. The students must design and construct the experimental apparatus and then obtain the heat transfer and design data required by Kodak. The experimental and logisti cal novelty of this project is that the process fluid is a gelatin solution and the students act as if in a consulting capacity to a contracting employer. This program will continue over several quarters and will require that students study the reports of preceding groups, building upon their progress. The wetted-wall column is a standard counter current gas / liquid contacting device. The students are ~ble to change tube dimensions and gas and liquid Reynolds numbers to examine mass transfer coefficients in different flow regimes. Water / air mass transfer data are compared to classical cor relations. The use of the column with surface ac tive agents and to concentrate viscous aqueous solutions has also been investigated. DISCUSSION Since our students only work on one project each quarter ( compared with the more standard rotation of four to six experiments), it appears that we are sacrificing breadth of exposure to different processes for in-depth studies of two topics. However, a single project quite often in volves learning how to use several equipment items or performing experiments (such as generation of fluid property data) which are frequently used as separate experiments in rotation-type lab courses. In addition, students can learn from the oral presentations and laboratory interactions with classmates. It has been our experience that the present system stimulates inter-group inter action. Feedback from our graduates reinforces our opinion that the uniqueness of the present ex perience far outweighs it drawbacks. The two major constraints on the lab are those that are common to many industrial and academic projects: time and money. Experimental set-ups are taken apart every year and, not infre quently, even after each quarter. New experi ments are frequently introduced and old experi ments are rotated in and out depending on student interest. In the second quarter the students are allowed to select new experiments of particular interest to them from among those we have the facilities to implement. As for old experiments SUMMER 1985 objectives often are changed for a new lab group in the second quarter, and may be different enough that modifications of the apparatus are required. To this end, we strike a cautious compromise be tween our available resources and our creative urges. Over the years we have also noticed a certain latency period in the first quarter of the lab. It usually takes the students several weeks to adjust from the cookbook-trained mentality to the point where they gain the confidence to rely on them selves. In several isolated cases we also have to deal with individuals who are over-enthusiastic and put unreasonable demands on the technical staff. Gradually, they all learn to deal with independence, bureaucracy, lab techs, and fellow group members who may not have the same motivation or philoso phy. Group dynamics are more obvious in the pres ent environment, since the lab group has to go through so many oral and written reports in ad dition to interactions with the project head. Students with leadership qualities, characters with nonchalent attitudes, "gofers," and any possible strains within a group are quite observable. CONCLUSION We feel that we are successful in developing the oral and written communication skills of our students, while providing a forum for innovative thought. We also have a lab which allows our students to get acquainted with new industrial developments, such as microelectronic fabrication and biotechnology, and with the integration of new technology, such as microcomputer applications, into laboratory experiments. The progress in oral communication skills is particularly significant and rewarding. We feel it is a direct result of the fact that each student has to give a minimum of six talks. (There are ad ditional opportunities for oral presentations in the computer-aided design and process design courses.) The emphasis is on the student making a very professional presentation We have received quite a number of comments from industrial em ployers commending us on the speaking abilities of our graduates. The improvement of the writing skills is a little harder to gauge, even though the students show obvious progress through the two quarters. As anyone who has taught a writing class knows, students have a notoriously high rate of reversion Continued on page 161. 155

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(eJ n I classroom FUNDAMENTALS OF CHEMICAL PROCESSES WILLIAM R. MOSER Worcester Polytechn i c Inst i tut e Wor c ester, MA 10609 THIS COURSE TEACHES the fundamental scientific principles controlling most chemical, petro chemical, and refining processes. The student popu lation consists mainly of junior and senior chemi cal engineers, but the information is of equal value to advanced chemistry majors. A few mechanical engineers interested in plant construction also take the course. The objective of the course is to pro vide the student with a fundamental understand ing of the chemical, catalytic and engineering sciences relating to the chemical reactions taking place in a variety of reactors of different configura tions. Although many major commercial processes are discussed in the course, the emphasis is not on an enumeration of all of the major processes, but the direction is placed on understanding how and why the chemical transformations occur. This s cience is then merged with the technology of the two dozen or so reactors of radically different de signs and configurations currently used com mercially. Thus, the student gains an understand ing not only of the process fundamentals but also of the devices used to successfully perform the processes. The course is kept current each year by introducing new processes which are in commercial development. Synthesis gas generation and utiliza tion are discussed to address a long range techno logical need of engineering and science students. For the chemical engineering students the course serves the specific function of allowing them to be come more conversant with chemical phenomenon. This is purposely done in response to the criticism from both industrial and academic scientists who feel that the current U.S. training of chemical engineers is deficient in chemistry. This course has a chemical orientation but it is placed in the con text of learning all of the fundamental sciences which govern the major commercial processes which they will deal with in the future. The student should gain enough fundamental understanding of the chemical phenomena occurring inside of re actors of different designs so that in their future 156 William R Moser has been a professor in the chemical engineering department at Worcester Polytechnic Institute since 1981. Sinc e earn ing his graduate degree in 1964 at MIT he has been active in the area of chemical proces s ing at CIBA E x xon and Badger His research interests are in mechan i stic studies of heterogeneous and homo geneous catalyzed reactions us i ng kinetic and in situ spectroscopic techniques He has several publications and patents and holds mem bership in a number of professional societies work they will be able to execute superior process designs and controls for these or other new pro cesses. COURSE DESCRIPTION The prior requirements fo r the course are a fundamental organic chemistry course, an intro ductory inorganic chemistry course ( usually in cluded in the freshman chemistry series), and a keen interest in chemical engineering and chemical processes. Since the course is descriptive and qualitative, prior chemical engineering cour s es in volving quantitative engineering calculations are not required. A successful presentation of the technology de scribed by this course requires the application of several principles of chemical engineering, organic, inorganic and physical chemistry, thermo dynamics, kinetics and mechanical engineering. Thus, the instructor must make a careful choice as to the degree of review of these subjects which is adequate for the understanding of the chemical process technology. The approach currently used at WPI is to provide a concise review of just those principles which are required to master the chemiCo p y ri gh t ChE D ivision, A S EE 1985 CHEMICAL ENGINEERING EDUCATION

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cal process concepts presented in the lecture of the day. LECTURES The technology presented in the course is ac complished in 24 lectures of 50 minute duration. In addition to outside reading from a list of 89 references taken from the original technical litera ture, three term papers are required on topics which are not discussed in the classroom lectures. Three one-hour, closed note and closed book exams are usually given during the duration of the course. The textbook currently used for the course is Chemistry of Catalytic Processes by Gates, Katzer and Schuit (McGraw Hill, 1979). The course is divided into the following eight major topics : 1. Survey of Major Chemical and Refining Processes 2. Homogeneous Catalytic Process Fundamentals 3. Heterogeneous Catalytic Process Fundamentals 4. Survey of Modern Commercial Reactor Configurations 5. Synthesis Gas Generation 6. Synthesis Gas Processes for Fuels and Chemicals 7. Technology of Major Advanced Chemical Processes 8. Major Refining Processes The division of lecture time committed to each topic may be seen in Table 1. The timing of exams and due dates for term papers is also shown. A TABLE 1 Chemical Technology: Course Schedule Lecture Number Subject 1 Survey Major Chemical Processes 2 Homogeneous Metal Catalysis (A) Major Processes 3 Homogeneous Metal Catalysis (B) Co-ordination Chemistry (C) Bonding (D) Reactivity 4 Homogeneous Metal Catalysis (E) Metals (F) Stereochemistry (G) Key Intermediates 5 Homogeneous Metal Catalysis (H) Key Transformations 6 Homogeneous Metal Catalysis (I) Ligand Effects on Reactivity (J) Classification of Reactions 7 Heterogeneous Catalysis (A) Major Processes EXAM-HOMOGENEOUS CATALYSIS FUNDAMENTALS 8 Heterogeneous Catalysis (B) Surface Adsorption (C) Surface Kinetics 9 Heterogeneous Catalysis (D) Surface Chemistry Problem Set #1 Due~Ziegler-Natta Catalysis 10 Heterogeneous Catalysis (E) Types of Catalysts 11 Heterogeneous Catalysis (F) Zeolites and Their Structures 12 Heterogeneous Catalysis (G) Zeolites and Their Catalysis SUMMER 1985 13 14 15 16 17 18 19 20 21 22 23 24 Reactor Configurations for Major Processes Synthesis Gas Catalysis and Synthetic Fuels Synthesis Gas Production Processes (A) Reforming EXAM-HETEROGENEOUS CATALYSIS FUNDAMENTALS Synthesis Gas Production Processes (B) Gasification (C) Downstream Processing Synthesis Gas for Chemicals and Fuels (A) Methanol Synthesis Problem Set # 2 Due-Catalytic Cracking Synthesis Gas for Chemicals and Fuels (B) Methanol to Aromatic Gasoline (C) ZSM-5 Catalysis Synthesis Gas for Chemicals and Fuels (D) Fischer-Tropsch Catalysis Synthesis Gas for Chemicals and Fuels (E) New Syngas Processes for Ethanol, Vinyl acetate, and acetic anhydride Problem Set #3 Due-Heterogeneous Partial Oxidation Synthesis Gas for Chemicals and Fuels (F) New Syngas Processes for Ethylene Glycol, Styrene, Xylenes Advanced Technology for Chemical Intermediates (A) Acetic Acid EXAM-SYNTHESIS GAS TECHNOLOGY Mature Technology for Chemicals (A) Wacker Process (B) Butane Oxidation (C) Hydroformylation Refining Processes (A) Hydrodesulfurization (B) Reforming 157

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brief description of the topics treated in the lec tures for the eight major areas listed above follows. 1 Survey of Ma j or Chemical and Refining P r ocesses The topic is introduced with a definit i on of the four principal types of reactions utilized in com mercial reactors, e g. heterogeneous catalyzed, homogeneous catalyzed, gas phase catalytic and non-catalytic, stoichiometric reactions in solution with their individual variations. Examples are given for each class. Also terms like conversion, selectivity, yield, etc are defined. 2 Homogeneous Catalytic Process Fundamental s Examples are given of the top fifteen com mercial processes using homogeneous catalysts. The student would be expected to know the re actants, products, catalysts, and approximate reThe objective of the course i s to p r ovide the student with a fundamental understanding of the chemica l, catalytic an d e ngin e ering sciences r elating t o t he chemica l reaction s taking place in a va r iety of r eacto rs of different configurations action conditions for each process. Several new processes which are currently being considered for commercialization are also listed. This section includes the important funda mental information on homogeneous catalysis. Thus, the key coordination chemistry principles required to understand the homogeneous catalyzed process (to be described later on) are tightly re viewed and discussed. A few of the concepts dis cussed are: elements of crystal field-molecular orbital theory; metal cl-orbitals; cl-electron activa tion of coordinated ligands; coordination stereo chemistries of transition metal complexes; count ing cl-electrons; eighteen electron rule; key inter mediates in homogeneous catalysis like metal car bonyls, hydrides, alkyls, etc.; key transformations in homogeneous catalysis like oxidative addition, insertion, electron transfer, etc.; ligand electronic and steric effects such as pi-acceptors, sigma donors, cone angles, etc. Then the basic sub-classi fication of homogeneous metal catalyzed reactions like main group and transition metal catalysis, bio catalysis, phase transfer catalysis, polymer sup ported catalysis, etc are briefly described. The typical kinetic treatments and methods for spectro scopic analysis are also illustrated. 158 3. Heter oge ne o us C a t a l y tic Process F u ndame n t a ls Fifteen examples are given of major com mercial processes in terms of reactants, products, catalysts, and conditions, along with a brief dis cussion of a dozen other processes. The fundamental aspects of heterogeneous catalyzed processes are discussed by reviewing principles of the chemistry and physics of surfaces and surface adsorption, e.g. macroand micro pores, Knudsen diffusion, chemisorption and physi cal adsorption; Langmuir-Hinshelwood and Ri deal-Eley surfaces kinetic models, competitive chemisorption and catalyst poisoning; surface intermediates and surface chemistry. This section also discusses the major sub categories of heterogeneous catalysts like support ed and unsupported reduced metals, solid state in organic catalysts, carbon catalysts, clays and zeo lite catalysts Several examples are given for each class. A detailed discussion is devoted to the struc ture, physical and chemical properties, and cataly tic properties of zeolites. Some of the topics dis cussed are Xand Y-type zeolites and ZSM-5 struc tures, modifications and molecular build up; pore openings and crystal structure; super acidity and super basicity; and a four component model for rationalizing the unusual activity of zeolite cata lysts. The student is also introduced at this point to the relationship of shape selectivity and con straint index to the crystal and catalytic proper ties of zeolites. An assortment of several classes of zeolite structures is illustrated with 35 mm slides and three dimensional molecular models. Support materials used in heterogeneous catalyzed processes and their criteria for selection are briefly discussed. 4. Surv ey of M odern Com me r cial React o r C o nfi gu r at i on s Drawings of fourteen of the reactor configura tions used commercially in both heterogeneous and homogeneous catalyzed processes are supplied to the student, and an example is given of a com mercial product produced using each configura tion. Within the discussion of these reactor con figurations, the various thermodynamic, heat transfer, kinetic, reactor stability, mixing and other factors giving rise to the selection of a spe cific configuration, are examined. Specific examples of reactor configurations (process ap plications) are as follows: tube and shell (Lurgi methanol and ethylene oxide process) ; tray reCHEMICAL ENGINEERING EDUCATION

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actor with interstage cooling (ICI methanol syn thesis) ; riser tube ( catalytic cracking) ; fluidized bed (SOHIO acrylonitrile) ; slurry tank (poly propylene) ; radial bed (styrene synthesis) ; and others. 5. Synthesis Gas Generation The major processes used in the production of synthesis gas are discussed along with their feedstocks and gaseous product compositions. The thermochemistry of each process is related to thermal and pressure effects on the syngas pro duct ratios and to its consequence on the reactor design. Drawings for several process reactors such as methane reforming, partial oxidation, Lurgi non-slagging gasifier, Koppers-Totzek gasifiers and the Bi-Gas slagging gasifier are provided to the student along with a discussion of each. A survey of next generation gasifiers is given. Post gasifier processing of raw syngas through water gas shift, bulk and trace sulfur removal pro cesses, CO 2 removal and CO separation from H 2 is discussed. The chemistry of a Claus plant and Stretford plant is summarized. 6. Synthesis Gas Processes for Fuels and Chemicals A survey of all commercial and potential fuels and chemicals processes using a syngas feedstock is given with reactants, products, catalysts, and reaction conditions. Details of the thermochemis try of methanol synthesis and its consequence on the evolution of the ICI, Lurgi and Chem Systems reactor and process configurations are discussed. The student is introduced to conventions used in process stream notations. The low pressure catalyst structure and syngas to methanol surface reaction mechanism are presented. A detailed discussion is given to the conversion of methanol by the Mobil M process to aromatic fuels. The details of the ZSM-5 catalyst structure, TABLE 2 Exam: Heterogeneous Catalysis Fundamentals and Commercial Reactor Configurations Part 1. Describe the following commercial processes using structural formulae of starting materials, major products and heterogeneous catalysts required in the process (A) Sohio Ammoxidation (B) Styrene Process (Two Steps) (C) Maleic Anhydride Process (D) Catalytic Hydrodesulfurization Process (C) Fischer-Tropsch Process (D) Mobil M Process Part 2. A. Describe the following adsorption processes for gaseous molecules on catalytic solid surfaces. Give examples of each. 1. Physical Adsorption 2. Chemisorption 3. Competitive Chemisorption B. Briefly describe how a Langmuir-Hinshelwood surface kinetic mechanism differs from a Rideal Eley mechanism. Give an example of each. Part 3. Draw the structural formulae of the following heterogeneous catalytic surface intermediates (A) Surface alkyl (B) Selective surface oxidant (C) Non-selective surface oxidant (D) Surface hydroxy Carbene (E) Bronsted acid surface site Part 4. Discuss the following properties of zeolites (A) Compare the 3A, 4A and 5A molecular sieves in terms of (1) ions used to modify these zeolites (2) size of pore opening for each SUMMER 1985 (3) example of molecules absorbed by each (B) Briefly compare the structures and differ ences in composition of the Xand Y -type zeo lites. (C) Describe the "Supercage" in a com mercial catalytic cracking catalyst in terms of (1) its geometric form and number of sides (2) size of its largest pore opening and (3) internal cage size. (D) Why are zeolite catalysts as much as 10,000 times more reactive than amorphous aluminosilicates in catalytic cracking? Part 5. (A) Sketch the reactor section for a commercial radial bed reactor showing the inlet reactant and product effluent locations and catalyst bed con figuration. (B) Why would one use such a complex reactor configuration in a commercial process? (C) Sketch the reactor configuration for a typi cal trickle bed reactor used in catalytic hydro sulfurization in a refinery. (D) What essential task does the trickle bed re actor perform which other designs do not ac complish. (E) What is a typical contact time in a riser tube reactor and which of the following catalysts would a refiner use in this reactor for catalytic cracking: (a) ZSM-5, (b) X-type zeolite, (c) Ca Y-type or (d) rare earth-Y-type? 159

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acidity, and shape selectivity are merged with a detailed evaluation of an intercrystalline surface mechanism to understand the product distribution and catalyst stability. A thorough discussion is devoted to the ARGE fixed bed and fluidized bed SASOL processes for the direct conversion of syngas to fuels. Catalysts, reactor configurations, slides of the Sasol II Plant, surface reaction mechanistic models, Schulz-Flory kinetics and thermochemistry of syngas conver sion to various products are parts of these lec tures. The lectures on the conversion of synthesis gas to chemicals is less oriented toward reactors and total processes; rather, they concentrate more on the detailed reaction mechanisms, using the per tinent coordination chemistry intermediates, to rationalize the conversion of syngas to various products. This is the first opportunity that the student has in the course to apply the funda mentals learned earlier to homogeneous and heterogeneous catalyzed processes. Some of the processes discussed are : acetic anhydride, acetic acid, ethylene glycol, vinyl acetate, and ethanol. 7. Technology of Major Advanced Chemical Processes This section also concentrates on reaction mechanisms for both homogeneous and hetero geneous catalyzed processes. Aromatic side chain oxidation and butane oxidation to acetic acid are described by listing each of the proposed indi vidual, elementary reactions required to form pro ducts. The coordination chemistry of the Wacker process, Carbide and Shell oxo-processes, Halcon propylene oxide process and others are illustrated. Likewise the proposed surface mechanisms for the super basic zeolite catalyzed conversion of toluene and methanol to styrene and ZSM-5 zeolite catalysts for p-xylene production are explored along with several other. 8. Major Refining Processes The principal processes utilized in a modern refinery are surveyed. A few of the processes like hydrodesulfurization are described in detail by way of an examination of the crystal chemistry of the catalyst, processing of various feedstocks, and reactor configuration. Most of the students' under standing of catalytic reforming, and catalytic cracking comes from assigned textbook reading. Several of the processes are viewed by 35 mm slides of various refinery units. 160 TERM PAPERS Three term papers are assigned for the purpose of examining the details of several important areas of chemical and petroleum processing tech nology which are not covered in class. The empha sis in the papers is to provide a concise descrip tion of the major scientific and engineering aspects of the technology. In the past, Ziegler-Natta catalysis, catalytic cracking and technology of heterogeneous, hydrocarbon partial oxidation were assigned. EXAMS Three one-hour exams are usually given which cover all material discussed in class. These exams are closed notes and books and are given soon after the subject matter is discussed in class. No comprehensive final has been given until now. Table 2 shows a typical exam, given in March of 1982. The high grade was 99, the low was 41, and the class average of 53 students was 70. JUNIOR YEAR LAB Continued from page 127. thanks go to Colin Pritchard, Norman Macleod, Mike Davidson, Jack Ponton, Don Glass, Leong Yeow and Jeff Lewis. REFERENCES 1. Macleod, N and R. B. Todd In t J. H e a t Ma ss Tran s f e r, 16, 485, 197 3 2. Kapur, D. N., and N Macleod, Ibid, 1 7 1151, 1974. 3. Paterson, W R., R. A. Colledg e J. I. Macnab, J. A. Joy, to be submitted to ibid 1985 4. Paterson, W. R., A. K. Banerjee, N. P. Clark, D. C. Knott, N. P. Wooley, to b e submitted 1985. 5 Scholtz, M. T. and 0. Trass AI C hE J 9, 548, 1963. 6. Bennett, C. 0. and J. E. Myers, Moment u m, H e a t a nd Ma ss T r an s fer, 3 rd ed. McGraw-Hill, Japan p 516-7, 1982. 7. Gover, T. A. J. C h e m. Ed uc ., 44 409, 1967. 8. Crosby, E. J., Exp e r i ment s in T r an s port Ph e nom e na, Wiley, NY, p 139, 1965. 9. Bird, R. B., W. E. Stewart, E. N. Lightfoot, Tran s port Phenomena, Wiley, NY, p 594, 1960. 10. Williams, R. D., Ch e m. Eng. Ed u c. Winter, 28, 1974. 11. Paterson, W. R. and D L. Creswell, Proc. 4th Int. / 6th Europ. Symp Chem. Rn. Eng Heidelberg, p 121, 1976. 12 Creswell, D. L and A. M. Santos, C h e m. Eng. Sci 35 283, 1980. CHEMICAL ENGINEERING EDUCATION

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LETTER TO THE EDITOR Continued from page 135. Another important refinement is to modify the impeller in the "mixer" which is a small centri fugal pump that blends together the reactant streams entering the reactor tube. In our particu lar reactor geometry, the impeller of the pump sent rapid pressure pulses back to the dye rota meter causing violent fluctuations of the bead in the dye rotameter. Our solution was to replace the impeller blade with a flat disc. The rotation of the disc generates sufficient shear to blend the streams. R. R. Hudgins University of Waterloo PACKAGED SOFTWARE Continued from page 147. these packages. To this end an increased student awareness and familiarity with these facilities can only be beneficial. ACKNOWLEDGMENTS The author wishes to acknowledge assistance and co-operation from the following members of staff: A. M. Gerrard, J. Notman (Department of Chemical Engineering), P.R. Bunn (Department of Electrical, Instrumentation and Control Engi neering), and research students J. C. Cheow, S. Acey, and C. K. Goh. REFERENCES 1. "Control of a Gas Absorption Column using the Self Tuning Regulator," C. K. Goh, J. C. Cheow, P. R. Bunn, and B. Buxton. Paper presented at Insti tute of Measurement and Control Symposium "Ap plication of Multivariable System Techniques", 31 October to 2 November 1984, Plymouth, UK. 2. Annual Research Meeting, Bath, 4 April 1984. Heat Transfer, Catalysis and Catalytic Reactors, 247. Heavy Oil Cracking. S. Acey, J.C. K. Lee, J. R. Walls. PROCESS LAB Continued from page 155. to bad habits as soon as they stop writing regular ly. The feedback from the students has been ex tremely positive. They fully enjoy the opportuni ty to work on what they regard as their own problems. We have not come across a course which SUMMER 1985 puts so much demand on the students but receives so few complaints. (The actual lab work extends well over the regular six hours per week scheduled in addition to the time required for report writing and preparing oral reports.) The support from industry has also been en couraging. We continually receive financial aid and equipment donations as well as new ideas for ex periments. In the next year we expect to receive an industrial scale CVD reactor, a spin coating ap paratus and an experiment to perform membrane separation of gasses. Our lab course would not have been so successful without this continued support. ACKNOWLEDGMENTS We would like to thank our industrial support ers-Chevron, Kelco, Eastman Kodak, and Komax -for their donations of equipment, materials, in formation, and money. Finally, we are indebted to the AMES department technical support staff Joe Robison, Paul Engstrom, Ray Hummer, and Jon Haugdahl-for their continued help and understanding (both with students and instruc tors!). REVIEW: Cost Engineering Continued from page 119. other new topics added to the first edition such as an analysis of overtime costs, information on rework costs, and the handling of back charges. These topics are illustrated by actual industrial examples. Additional new information on bulk material control, monitoring construction field labor overhead, labor productivity, and forecast ing direct labor are illustrated with other in dustrial examples. The chapter on contingency estimating and its application to cost control has been rewritten to reflect recent developments. The treatment of estimate types and accuracies like wise has been updated. Because of the omnipres ent computer, an introduction to computerized estimating has been added since the first edition. Advice is provided on how to go about computeriz ing routine estimating tasks. This edition is the first book in a planned series of about 20 which concern cost engineering and related topics. Of the twenty, six have al ready been published. This series will cover the whole gamut of cost engineering topics for the student and for the practicing cost engineer. 161

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kift;lviews and opinions ADJUNCT POSITION One Way to Keep Up With Technology and Education RICHARD D. NOBLE Uni v ersity of Colorado Boulder, CO 80309 A GREAT DILEMMA IN engineering education is how an individual can become an excellent teacher and also keep up with the latest technical developments in his field. This is especially diffi cult during this present period of rapid techno logical advance in many fields, such as computers, and the emergence of new fields, such as biotech nology. What are some of the problems associated with an academic professional keeping up in both technology and education? An instructor normally has had little or no formal training in educational skills. Also, at many schools there is a lack of emphasis and a lack of rewards for good teaching. This makes it difficult for an individual to develop the necessary skills to be a good teacher. In technical research, the emphasis at many universi ties is to obtain contract research. This in itself is a difficult task. Once the funding is obtained, it may be very difficult to perform good work due to a lack of graduate students, poor laboratory and / or computer facilities, or an inadequate li brary. There are many possible avenues to solving this problem. Sabbaticals, leaves of absence, con sulting, and graduate research are all possible means for keeping up with technical advances, while attending educational meetings and semi nars can help to improve teaching skills. This paper describes an approach that the author has used to keep up with both technology and education: combining technical work at a national labora tory with an adjunct faculty position at a uni versity. At a time when there are still many unfilled faculty positions, this approach provides one method to deal with the problem. Some faculty C o p 11ri11ht ChE D ivisi on ASEE, 1985 162 TABLE 1 Some Benefits of An Adjunct Position PROFESSOR Develop teaching skills Conduct technical research Modern facilities Interaction with students Publications 12 month salary EMPLOYER Employee morale Public relations Highly skilled employee Student labor Recruitment of students UNIVERSITY Inexpensive labor Additional faculty Public relations Added technical skills STUDENTS Exposure to modern technology Work with modern facilities may view an adjunct position as a temporary (one to three-year) method to develop research skills while still "keeping up" educationally. THE POSITION AND BENEFIT I currently have a position as a chemical engi neer doing research in mass transfer separations at a national laboratory. My job description also allows me to teach one course per semester as an adjunct faculty member. I teach one graduate course and one undergraduate course in transport phenomena (the same subject area as my techni cal work) The laboratory allows me time to per form my teaching duties and to attend education al meetings such as the ASEE annual meeting. The chemical engineering department pays my travel expenses to these educational meetings in lieu of salary. An outline of some benefits is shown in Table 1. C HEMICAL ENGINEERING EDUCATION

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Richard D. Noble received his B E degree in 1968 and M E de gree in 1969 from Stevens Institute of Technology. In 1976, he received his PhD degree from the University of California Davis. His current research in liquid membranes, transient heat transfer and problem solving skills. What are the benefits to me? I can continue to use and improve my teaching skills by continued teaching and by attendance at educational meet ings. I keep up with the material in the area of transport phenomena by continued teaching and technical research, and I keep up with the techni cal advances in my field by conducting research and attending technical meetings. I can use up to-date facilities to conduct research. I get to inter act with both undergraduate and graduate students and work with them on research projects. Continued educational and technical work allows me to publish in educational and technical journals. I also have a 12-month salary, so I do not have to develop additional summer support for myself. What are the benefits to my employer? First, they have a happy employee. If I am enjoying my job, they benefit. They also get the public relations benefit of demonstrating their support for higher education by having an adjunct faculty on their staff They have an employee who is technically "up" in his field through continued teaching in his subject area, and they enjoy the benefits of "cross-fertilization" through interaction with uni versity colleagues. The employee also develops communication skills through teaching. Students work at the laboratory for a small salary or for credit (no salary), so the labor force is inexpensive and usually productive. Some of the students may decide to work for the employer upon graduation because of their work experience, so there is also a recruitment aspect for the employer. What are the benefits to the university? They SUMMER 1985 get "cheap" labor in a time of fiscal restraints and they get a faculty member in a time of faculty shortages. They get the public relations benefit of having teachers who have up-to-date technical knowledge, and they also get additional technical skills in their department. Last, but not least, what are the benefits to the student? Students are exposed to modern tech nology as it is introduced in the classroom by the adjunct instructor. They have an instructor who is "up-to-date" and who can translate the concepts learned in class to new developments in technology. For students who work with the adjunct professor, there are added benefits. They get to use modern "state-of-the-art" equipment, and through their work they can gain experience in certain jobs and determine if they wish to pursue them after graduation. For graduate students, working with modern facilities can make their work more pro ductive since they spend less time reducing data and maintaining equipment. There can also be negative aspects to this type of arrangement. Adjunct faculty have little or no time to meet with students outside of class. If the adjunct has had limited training in teaching, the communication of information between faculty and students can be impaired. A job such as I have described requires the full and continuing support of both the employer and the university. If that support is lacking, it would be very difficult to do a good job. CONCLUSION Combining technical training with an adjunct faculty position has been shown to be an effective mechanism for maintaining technical and educa tional skills. Benefits to the individual, the employ er, the university, and the student are varied and important. The particulars of an adjunct position are often flexible and depend on the interests and objectives of the parties involved. ACKNOWLEDGMENT This paper was originally presented at the ASEE Gulf Southwest Regional Conference, Uni versity of Houston, March 13, 1982. A revised version was presented at the ASEE Summer School for Chemical Engineering Faculty, Uni versity of California, Santa Barbara August 1-6, 1982. I am indebted to the many individuals who have provided comments during these presenta tions. 163

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TEACHING PROCESS DESIGN Continued from page 123. The cold gas is warmed in the heat exchanger to 65 F and leaves with an enthalpy of 161 Btu / lb. Since the mass flow is the same on both sides of the heat exchanger, the enthalpy decrease of the liquid CO 2 is the same as the enthalpy in crease of the cold gas, which is (161-148) or 13 Btu / lb. The enthalpy of the liquid going to the valve (and entering the condenser) is now (6513) or 52 Btu / lb. So the refrigeration is 45,300 (148 52) = 4,350,000 Btu / hr The student recognizes that the high-pressure heat exchanger might be expensive (he suggests that the high pressure liquid would flow through tubes and the 200 psia gas through the shell) and doesn't know if the extra 590,000 Btu / hr of re frigeration would warrant the cost of this ad ditional piece of equipment (he hopes that he will soon get a course which will enable him to answer such questions) DISCUSSION The possible ramifications of this sort of de velopment of a thermo problem are enormous. But this is a course in thermodynamics and must move along-there is a lot more subject matter to cover. The problem has been a good workout in the use of a Monier diagram and in the applica tion of the first law flow equation to heat transfer equipment and to a Joule-Thomson expansion, as well as the calculation of isentropic compression pow-or. The calculations are simple so as not to divert the student from the ideas introduced. Ele mentary concepts of process design are encounter ed (possibly for the first time), and the student has an opportunity to invent and compare alter native process schemes. There is a continuous feedback from analysis to better design. There are many angles which can be developed in the discussion. The book and the course lec tures have seemed to suggest that reversible pro cesses are highly desirable. What are the ir reversible features of the fourth student's flow sheet? Can they be reduced or eliminated? Can the common work functions ("availability") be used to calculate the operation of a wholly re versible process. Can a completely reversible pro cess be described? Could an expansion engine be employed? Could the heat exchangers be made reversible, even with a zero temperature differ ence at one end? Is counter-current flow in the 164 exchangers desirable or necessary? What is the origin of the stipulation of a 5 F minimum temperature difference? The second student found the high pressure gas to liquefy partially in passing through the valve. Is this phenomenon peculiar to CO 2 ? Could the book formulas for the Joule-Thomson coefficient be useful? What ex perimental procedures were employed to get the data on which the Mollier chart is based? If we had had no chart, could we have made useful calculations? Could we make a similar analysis for the case of a natural gas well (pure methane; or 90 % methane, 10 % ethane)? Would it be better to use a separate ammonia refrigeration plant, or possibly some combination of ammonia refrigeration plus Joule-Thomson expansion of the gas stream? Where would cooling water come from in New Mexico? What are water cooling towers and how do they work? Why 200 psia in the pipeline? Etc., ad infi ni tum. DIFFICULTIES OF THIS APPROACH The possibility of introducing design thinking into theoretical subjects depends primarily on the interest and competence of the instructor. It can be done, for some M.I.T. instructors have been doing it for years. My department's most success ful teacher, Dr. W. K. Lewis has done this sort of thing all his life. Students in engineering generally like the approach and find that it helps them greatly to understand the theory. The instructor who worries continually about the things he must "cover" hesitates to "take the time out" for this sort of discussion. Instructors often lack the practical engineering background to do it successfully. Such background (and ma terial for good problems) often comes from high level engineering consulting work. The rise of engineering science and the increased consult ing work by younger staff members may have resulted in most of the staff's consulting being devoted to the more scientific "analysis" kind of activity, rather than to engineering design. It might even be suspected that only about half of the M.I.T. engineering staff are true engineers in the sense of being competent in design, and that the :raction is getting smaller. The most im portant single thing M.I.T. can do to improve the illstruction in engineering design is to en gage more instructors who are enthusiastic about the subject and who have not yet become so enamoured of engineering science that they have lost interest in design. CHEMICAL ENGINEERING EDUCATION

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ACl{NOWLEDGMENTS Departmental Sponsors: The following 152 departments contributed to the support of CHEMICAL ENGINEERING EDUCATION in 1985 with bulk subscriptions. University of Akron University of Alabama University of Alberta Arizona State University University of Arizona University of Arkansas University of Aston in Birmingham Auburn University University of British Columbia Brown University Bucknell University University of Calgary California State Polytechnic California State University, Long Beach California Institute of Technology University of California (Berkeley) University of California (Davis) University of C a lifornia (Lo s A ngeles) University of California at San Diego Carnegie-Mellon University Case-Western Reserve University University of Cincinnati Clarkson University Clemson University Cleveland State University University of Colorado Colorado School of Mines Colorado State University Columbia University University of Connecticut Cornell University Dartmouth College University of Dayton University of Delaware Drexel University University of Florida Florida State University Florida Institute of Technology Georgia Technical Institute University of Houston Howard University University of Idaho University of Illinois (Chicago) University of Illinois (Urbana) Illinois Institute of Technology Institute of Paper Chemistry University of Iowa Iowa State University Johns Hopkins University University of Kansas Kansas State University University of Kentucky Lafayette College Lamar University Laval University Lehigh University Loughborough University of Technology Louisiana State University Louisiana Tech. University University of Louisville University of Lowell University of Maine Manhattan College University of Maryland University of Massachusetts Massachusetts Institute of Technology McMaster University McNeese State University University of Michigan Michigan State University Michigan Tech. University University of Minnesota University of Missouri (Columbia) University of Missouri (Rolla) Monash University Montana State University University of Nebraska University of Newcastle University of New Hampshire University of New Haven New Jersey Inst. of Tech. New Mexico State University City University of New York Polytechnic Institute of New York State University of N.Y. at Buffalo North Carolina State University University of North Dakota Northeastern University Northwestern University University of Notre Dame Nova Scotia Tech. College Ohio State University Ohio University University of Oklahoma Oklahoma State University Oregon State University University of Ottawa University of Pennsylvania Pennsylvania State University University of Pittsburgh Princeton University Purdue University Queen s University Rensselaer Polytechnic Institute University of Rhode Island Rice University University of Rochester Rose-Hulman Institute Rutgers University University of South Alabama University of South Carolina University of Saskatchewan South Dakota School of Mines University of Southern California Stanford University Stevens Institute of Technology University of Surrey University of Sydney Syracuse University Tees s ide Polytechnic Institute Tennessee Technological University University of Tennessee Texas A&I University Texas A&M University University of Texas at Austin Texas Technological University University of Toledo Tri-State University Tufts University Tulane University University of Tulsa University of Utah Vanderbilt University Villanova University University of Virginia Virginia Polytechnic Institute Washington State University University of Washington Washington University University of Waterloo Wayne State University West Virginia Col. of Grad Studies West Virginia Inst. Technology West Virginia University University of Western Ontario Widener University University of Windsor University of Wisconsin (Madison) Worcester Polytechnic Institute University of Wyoming Yale University Youngstown State University TO OUR READERS: If your department is not a contributor, please ask your department chairman to write CHEMI CAL ENGINEERING EDUCATION, c / o Chemical Engineering Department, University of Florida, Gainesville, Florida 32611.


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