Chemical engineering education ( Journal Site )

Material Information

Chemical engineering education
Alternate Title:
Abbreviated Title:
Chem. eng. educ.
Physical Description:
v. : ill. ; 22-28 cm.
American Society for Engineering Education -- Chemical Engineering Division
Chemical Engineering Division, American Society for Engineering Education
Publication Date:
annual[ former 1960-1961]


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


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-

Record Information

Source Institution:
University of Florida
Rights Management:
All applicable rights reserved by the source institution and holding location.
Resource Identifier:
oclc - 01151209
lccn - 70013732
issn - 0009-2479
sobekcm - AA00000383_00032
lcc - TP165 .C18
ddc - 660/.2/071
System ID:

Full Text

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-- ----


Your parents didn't put you through school

to work for the wrong company.

We think we're the right company.
We're big, but not too big.
We've climbed halfway up Fortune's
Directory of 500 Largest Corporations.
But compare the share of sales that
paper companies plow back into research.
Suddenly, we're no less than second.
What does this mean when you're
considering a career in paper production?
It means that production engineering
at Westvaco is influenced by continuous
research feedback. It means lots
of development work. Diversification.
Excitement. Research has given us
processes and equipment to make better

papers for printing, packaging, and
structures. But we need to continually
improve our processes. Speed them up.
Make them more efficient. That's your job.
Research has given us useful by-products,
too. High-grade specialty chemicals for
coatings, pharmaceuticals, inks and waxes.
And activated carbon adsorbents and
systems to alleviate water pollution.
But we need good engineers to recover
these by-products more efficiently. To
improve them. To find new uses for them.
In our company, working with paper
and paper by-products can mean good
careers in design engineering,

fluid dynamics, specialty chemicals,
process control, process R & D
and product development. And more.
Chances are, whatever you liked
and did best in college, we're doing
right now. And doing it well.
But find out for yourself. See our
campus representative, or contact
Andy Anderson, Westvaco,
299 Park Avenue, New York 10017.
Remember, all your parents want for
you is the best of everything. The least
you could do is join the right company.

An equal opportunity employer


t ,-

Department of Chemical Engineering
University of Florida
Gainesville, Florida 32601

Editor: Ray Fahien
Associate Editor: Mack Tyner
Business Manager: R. B. Bennett

Publications Board and Regional
Advertising Representatives:
CENTRAL: James H. Weber
Chairman of Publication Board
University of Nebraska
Lincoln, Nebraska 68508
Richard S. Mayer
Ohio University
Athens, Ohio 45701
WEST: William H. Corcoran
California Institute of Technologjy
Pasadena, California 91109
SOUTH: Charles Littlejohn
Clemson University
Clemson, South Carolina 29631
University of Houston
Houston, Texas 77004
EAST: Robert Matteson
College Relations
Sun Oil Company
Philadelphia, Pennsylvania 19100
G. Michael Howard
University of Connecticut
Storrs, Connecticut 06268
George D. Keeffe
Newark College of Engineering
Newark, New Jersey, 07102
Peter Lederman
Brooklyn Polytechnic Institute
Brooklyn, New York 11201
Thomas W. Weber
State University of New York
Buffalo, New York 14214
NORTH: J. J. Martin
University of Michigan
Ann Arbor, Michigan 48104
NORTHWEST: R. W. Moulton
University of Washington
Seattle, Washington 98105
D. R. Coughanowr
Drexel University
Philadelphia, Pennsylvania 19104
Stuart W. Churchill
University of Pennsylvania
Philadelphia, Pennsylvania 19104
University of California
Santa Barbara, California 93106
Secretary's Department
E. I. du Pont de Nemours
Wilmington, Delaware 19898

Chemical Engineering Education

55 Views and Opinions
Relevance of Academic Chemical Engineer-
ing Research, S. G. Bankoff.
57 Letters from Readers
58 Departments of Chemical Engineering
"Mr. Jefferson's Academical Village,"
V. W. Uhl
64 The Educator
Professor Alan Randolph
72 International Chemical Engineering
Soviet Education: from Detsky Sad to
Aspirant, Alan and Irmgard Myers
The Laboratory
78 Stability of Reaction Systems
J. B. Anderson
82 A Demonstration Experiment in Non-
Newtonian Flow, F. Rodriguez
88 The Curriculum
M. S. Core Courses in Air Pollution,
R. B. Grieves
90 The Classroom
Process Dynamics, without Control,
J. C. Friedly
96 AIChE Annual Reports
Education Projects Committee,
L. Bryce Andersen
Continuing Education Committee,
K. D. Timmerhaus
98 Book Review
99 Problems for Teachers
Simplified Approach to Polytropic
Processes, F. M. Tiller and Fred Lowry
75 News
Feature Articles
68 Improving the Lecture:
Semi-notes Can Help, R. A. Mischke

CHEMICAL ENGINEERING EDUCATION is published quarterly by the 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 DeLand, Florida. Correspondence
regarding editorial matter, circulation and changes of address should be addressed
to the Editor at Gainesville, Florida 32601. 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 Printing Co., P. 0. Box 877,
DeLeon Springs, Florida 32028. Subscription rate U.S., Canada, and Mexico is $10 per
year to non-members of the ChE Division of ASEE, $6 per year mailed to members
and $4 per year to ChE faculty in bulk mailing. Individual copies of Vol. 2 and 3
are $3 each. Copyright c 1971, Chemical Engineering Division of American Society
for Engineering Education, Ray Fahien, Editor. 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.




We have a lot to do in the next few years if man is to survive. The key prob-
lem is overpopulation. The U.S. population is gaining 6,035 daily, 82% babies.
In order to live, we have to obtain certain things from the Earth. In order to
have meaningful, happy lives, we have to preserve the quality of our environment.
We have already suffered irretrievable losses. No matter what we do now, no
matter how wise we are, there will be great future losses.
The only long-range solution is population stability achieved by the one or
two child family.

Some population-related problems

Air: smog, noise, fallout
Water: sewage, thermal, industrial
Land: garbage, litter, junkyards, mining, roads
Biological Systems: pesticides, bioactive chemi-
cals, radioactivity

Indifference-cheapening of life
Jams-traffic, airways
Congested parks

Space-hiking, thinking

Energy-oil, gas, coal, uranium
Land-open space, forests, agriculture, recreation

Schools-higher education
Hospitals-medical care
Services-fire, police, courts
Transportation-highways, mass transit, airports

296 million in U.S. and 6 to 7 billion on earth by
2,000 A.D.
Without ZPG, mass famine with 25 billion by
2,070 A.D.

Recommended reading on population and environmental problems:
1. The Population Bomb by Paul Ehrlich (Sierra Club-Ballantine).
2. Moment in the Sun by Robert Rienow and Leona Train Rienow (Sierra Club-
(Above 2 books available from ZPG, postpaid $1.00 each)
3. Famine-1975! by William & Paul Paddock (Little, Brown).
4. Population, Evolution, and Birth Control-A Collage of Controversial Ideas,
assembled by Garrett Hardin (Freeman).

litical action organization whose purpose
is to bring about population stability in
the United States, then in the rest of the
world. We will achieve this end by po-
litical and educational means.
* ZPG has chapters throughout the
United States. These chapters are working
units. Many are in college communities.
* Our earth is burdened by 8,292 addi-
tional people per hour-all infants.

To join ZPG and receive the monthly Newsletter, fill out this
form and return to:
Zero Population Growth
330 Second St.
Los Altos, California 94022



D Set of Literature $1.50
D General: $10 annually
D Student: $4 annually

State (zip)



B views and opinions



Northwestern University
Evanston, Illinois 60201

The word "relevance" has taken on many hues
and shades of meanings in recent years, and it has
been particularly overused in academic circles. It
denotes, however, a valid concept with relation
to engineering, which must be relevant to the
needs of society if it is to fulfill its mission, and,
in fact, if it is properly to remain a professional
activity. Chemical engineering has expressed its
awareness of societal needs mainly through the
chemical industry, which employs engineers to
translate the discoveries of science (principally
chemistry) into useful products at a price which
is attractive to large segments of society. In
recent years the role of the chemical engineer has
been broadened to include contributions to envir-
onmental, health, and food and energy production
problems of society at large, but the principal
channel for his efforts has been, and remains, the
chemical industry. The relations between aca-
demic departments of chemical engineering and
industry are, therefore, still of prime concern, as
discussed recently in the Wilke report.1 This re-
port makes a number of recommendations of a
general nature for strengthening the ties between
chemical engineering academia and industry, such
as personnel exchange programs, advisory
boards, etc., but does not concern itself with the
nature of the research bond between the two
groups. This bond has become progressively
weaker in the past twenty years, for perhaps
very understandable reasons.
One factor is the increasing role of techno-
logical obsolescence among practicing engineers
of all ages, due to the highly scientific and mathe-
matical directions in which engineering research
has developed, and the accelerating pace of that
development. These are facts which cannot be
blinked away, and which call for greatly expanded
programs, both on the part of universities and

1. Wilke, C. R., Chem. Eng. Progress 65, 20 (1969).

Professor Bankoff writes: "The relevant part of my
autobiography would be that I have spent six years with
DuPont and Sinclair before entering teaching, that I and
my students have been prolific contributors to the chemi-
cal engineering research literature, and that I have been
Chairman of the Education and Accreditation Committee
of AIChE, as well as AIChE Observer for the Engineer-
ing and Accreditation Committee of E.C.P.D. for nearly
three years. In 1967, I was a Shell Visiting Professor at
Imperial College, London, and a Fulbright Lecturer in
Scandinavia and Israel. Purdue named me a Distinguished
Engineering Alumnus in 1970. I have four children rang-
ing in age from 10 to 25, and from a student of the violin
to a lawyer. I prefer squash, but also play handball (viz.
the tournament held at Northwestern during the Chicago
AIChE meeting for visiting chemical engineering pro-

professional societies, for continuing education at
all levels, and geared to a variety of needs. Less
easy to overcome are management attitudes
towards monitoring the academic chemical engi-
neering literature, on the grounds that the cost is
not worth the likely return on investment. This is
manifested in the opinion, sometimes stated by
middle management, that if several of the chemi-
cal engineering research journals were to be de-
layed in publication for two years, little would
be lost.
There are, of course, some elements of truth
in these assertions, and to that extent they must
be treated with serious concern. There is also
clearly an atrophy of communication channels,
and this cannot help but damage the profession.
As an example, there has been a considerable
effort in academic circles on chemical reactor de-
sign, including stability analysis, optimal design
by variational methods, and, most recently, a num-
ber of papers on optimal operating policies for
decaying-catalyst reactors (which include virtu-
ally all real reactors). However, an informal sur-
vey of design and computer groups of several


. . one should not lose sight of the fact that academic research should be relevant, not solely to the needs
of industry, but basically to those of society, which supports it through tax dollars. The engineer has a respon-
sibility to consider, therefore, the social consequences of his work, and insofar as he can, to guide it in a
direction which will add to, rather than subtract from, the sum total of human happiness.

major companies recently turned up the informa-
tion that this work had had very little impact,
if any, on their current operating or design pro-
Why has this isolation into separate compart-
ments come about? In Europe academic chemical
engineering research is much more practically
oriented, and this points to a principal element in
the present syndrome. It is as true now as in earl-
ier times that he who pays the piper calls the
tune, and less than 10% of current chemical engi-
neering research support in American universi-
ties is obtained from industry. Professors have
oriented their research proposals towards impress-
ing their peers and their colleagues in the funding
agencies, and this, in turn, has led to an emphasis
on scientific innovativeness, rather than applied
Now all this is not necessarily bad. One of the
oldest complaints of the man who cannot under-
stand current research is that it is all imprac-
tical, which is invariably accompanied by the as-
sertion that the old problems are still important.
Historically, there has always been a lag between
academic engineering research and practical ap-
plication, although of late this has become shorter
and shorter. Thus, there was an exponential in-
crease in the number of papers devoted to thin-
shell theory in the late forties, until in the early
fifties the first monococque airplane wing was in-
troduced. More recently, the development of op-
timal control theory and the design of space
vehicle trajectories have proceeded almost simul-
taneously. Academic engineering research is sel-
dom of lasting value when it addresses itself di-
rectly to industrial development or production
problems. On the other hand, it should not lose
sight of these problems, and, in some sense, it
should be motivated by them. One distinction that
has been made between the applied mathemati-
cian and the theoretical engineer is that the engi-
neer solves specific theoretical problems of an
engineering nature, while the applied mathema-
tician tries to generalize these problems by study-
ing their mathematical structure. In the same
way, academic chemical engineering research
should rarely deal with specific chemical process
developments, but instead should be concerned

with basic principles and generalizations of in-
dustrial and societal problems. To the extent that
this connection is lost, to that extent the research
tends to become isolated and sterile.
What can be done to bridge the gap? Clearly,
new and more effective means of communication
must be set up. One avenue which has not been
fully exploited in chemical engineering is the
specialist conference, dealing with a particular
area of technical interest, and usually lasting sev-
eral days. These should feature leading contribu-
tors, both academic and industrial, to the field,
and the program should allow for a thorough re-
view and discussion of current aspects and future
goals. The Gordon Research Conferences and the
Engineering Foundation Conferences are examples
of useful specialist conferences, but the central
areas of chemical engineering have rarely been
touched. A considerable expansion of these spe-
cialized conferences, designed on a regular and
periodic basis to attract participants, both aca-
demic and industrial, on an international basis,
would be most helpful in providing a forum for
concerned research and design persons from both
sides of the fence to get together in a critical and
constructive fashion.
It may also be that a new type of journal or
newsletter should be initiated, in order to bring
the methods and results of current chemical engi-
neering research to both industrial and academic
readers in understandable, uncomplicated lan-
Finally, one should not lose sight of the fact
that academic research should be relevant, not
solely to the needs of industry, but basically to
those of society, which supports it through tax
dollars. The engineer has a responsibility to con-
sider, therefore, the social consequences of his
work, and insofar as he can, to guide it in a direc-
tion which will add to, rather than subtract from,
the sum total of human happiness.

from our READERS
Sir: In response to your Editorial (Winter 1971)
I must agree with your statement that papers
published in CEE would not have been published in CEP.


The whole rationale of the development of CEE was
that papers of the type you have been publishing were
not being published. Now that you have done this suc-
cessfully, the obvious conclusion is that these papers
should have been published in the past elsewhere. That
is not sufficient reason as far as I am personally con-
cerned to discontinue CEE.
If everyone agrees that the publishing of the papers
of the type you have published is a good idea, either
there should be more support from AIChE for the pro-
gram, or AIChE taking over the program in its present
form, or rearrangement of the plans for CEP to include
papers like the ones you have been presenting. My per-
sonal feeling is that CEP and CEE are complementary
and do not interfere with each other.
I hope that there will be an opportunity to continue
CEE with its present focus. One way to enhance its
impact is, like you say, to be sure that all people who
are concerned with chemical engineering know that it
exists. I do not believe that is the case with many of
the industrial engineers at the present time. Those that
have seen the magazine, in my opinion, have been very
interested in reading it subsequently. We need to get
the magazine before those people. That is one of our
major problems at the moment.
Wm. H. Corcoran
California Institute of Technology

Editor's note: We appreciate this and similar indications
of support that we have received.


Sir: The following is a short announcement of a
summer program at Massachusetts Institute of Tech-
nology, June 22 through July 1, 1971, on "NEW DEVEL-
This special summer program will present basic
principles necessary to understand and apply new tech-
niques for computer-aided design and control of indus-
trial-scale chemical processes. Topics to be covered include
steady-state process stimulation, optimization techniques,
unsteady-state process simulation, computer-oriented
methods for estimation and correlation of physical
properties, and comprehensive problem-oriented comput-
ing systems for chemical process design. Contact: Direc-
tor of the Summer Session M.I.T., Room E19-356
Cambridge, Massachusetts 02139.
L. B. Evans
Massachusetts Institute of Technology.

Sir: Since the advent of Transport Phenomena, the chem-
ical engineer has become increasingly aware of the
proper use of conservation laws in the lumped and
distributed parameter simulation of physical systems.
Coupled with the computer revolution, the chemical en-
gineer has, for the first time, really begun to look at the
variability in the system parameters as a means of in-

creasing the validity of the simulation. A classic example
of this trend is in the use of the temperature variable
heat capacity term in the analysis of unsteady-state
stirred tank processes. Despite the ready availability of
transport-oriented textbooks, we still see some throw-
backs to "pre-Birdian" methods of analysis when faced
with the problem of what to do with the variable param-
eter terms. There is hardly a chemical engineering text-
book on the market today, with the exception of Aris'
new chemical reactor analysis book, which has not in
some way erroneously incorporated the variable heat
capacity term into the unsteady-state thermal energy
balance. Should the variable heat capacity term be inside
or outside of the temperature derivative term in the
energy balance? We wish to pin-point the origin of the
question by referring to an example from Himmelblau
and Bischoff, "Process Analysis and Simulation," page
30, Example 2.5-1, 1968. We would like to make it
abundantly clear that this example from Himmelblau
and Bischoff in no way detracts from their otherwise
excellent textbook. Their example 2.5.1, page 30, is only
slightly in error. It is the things not said that are of
great consequence in the general use of their example
problem for variable heat capacity cases. To ease the
burden of the presentation, we shall use their nomen-
clature exclusively and commence our derivation using
their equations (a) and (b), page 30, Thus,
t- (pvS)in (>)

^= [( +P. i)pvS]V (+)
By letting K = Et = Ut, and (pvS)in = v equations (a) and (b)

Tt- Oi + pi)(O) = 0 (b1)

The initial condition in equation (bi) reflects the idea
that the walls of the tank are radiating at Ti, initially.
The walls have no heat capacity. Basically, the system
equations (a') and (bl) describe the unsteady-state fill-
ing of an insulated evacuated tank with helium gas.
Equation (a') represents the unsteady-state mass bal-
ance and equation (bh) describes the unsteady-state ther-
mal energy balance. The thermodynamic system is the
mass of helium gas in the tank at any time. The system
boundary is the wetted surface of the tank.
The reference temperatures are rarely needed expli-
citly in a derivation of this kind. At any time,
=-t v0 + (c)
dt + 1i3V
Using equation (al), we can unfold equation (c) into
ait -
mt -- = ii t) + Vipi (a)

The term pVi is given for an ideal gas by
P 7= (M-W.) (e)
Therefore, equation (d) becomes
d-t = iw RTi
t + w. (r)
(Continued on page 66)



"Mr. Jefferson's Academical Village"
Professor Vincent W. Uhl
discusses chemical engineering "This institution will be based on the illimitable freedom
at the University of Virginia. of the human mind. For here we are not afraid to follow
truth wherever it may lead, nor to tolerate any error so
long as reason is left free to combat it."-T. Jefferson

".1 We are reminded by quotations such as this, and also by the
buildings and grounds at the core of the University of Virginia
that Thomas Jefferson had a great deal to do with our institution.
His "academical village" was founded in 1819; it was his major
preoccupation when he retired from public life. Mr. Jefferson
designed its first curriculum, recruited faculty, laid out the grounds
and served as architect for its buildings. They were designed in a
classical, peculiarly American Style, which set the pattern for the
buildings to follow. In fact, his neo-classic mode had a profound
effect on architecture in the United States in the nineteenth
The growth and influence of the University was seriously in-
terrupted by the Civil War; in the twentieth century it regained
its leadership and gradually increased its enrollment. At present
the student body, including Law and Medicine total about 11,000,
a number which might be considered modest particularly for a
state university. Many feel that this size is ideal, but the growth
is now accelerating toward an estimated size of 18,000 a decade
SMany rich, live customs and traditions contribute to provide
a unique character. Outstanding is the effective Honor System,
which has been student controlled and administered since its in-
ception in 1842. Our legendary "coat and tie" has almost vanished,
but most students are still neat in appearance. And there have
been drastic changes; beginning this year, we have become, like
most state schools, totally co-educational. Needless to say the
immediate effect has been pleasant and the engineering students
applaud it.
Visitors are impressed by the overall aspect of the university
and its location. The buildings and grounds, both the central
6 "academical village" and their considerable extensions, present


a fine environment. This is the result of inspired
original planning and conscientious efforts to
retain the original beauty. Many of the buildings
were designed to present vistas of the beautiful,
rolling countryside. In addition, the university
is located on the edge of a city of 36,000, cos-
mopolitan in character yet somewhat isolated.
Charlottesville is 115 miles southwest of Wash-
ington, and 70 miles west of Richmond in central
Virginia; the Blue Ridge mountains are a few
miles west. We find that the general resulting
atmosphere not only makes for good living, but
is also conducive to scholarly discussion and

Engineering has been offered since 1836. At
present about 1350 students are enrolled in the
School of Engineering and Applied Science, 350
of whom are doing graduate work. We have the
usual major engineering departments, plus Ma-
terials Science for only graduate work, and
Nuclear Engineering. Biochemical Engineering
also deserves mention. Representing a coopera-
tive effort by the Engineering and Medical
Schools, it currently has a staff of 13, 23 graduate
students, and two postdoctorates; it offers only a
doctoral program. Over the years, the School
has also set up divisions to offer undergraduate
courses of the quality and emphasis needed in
Graphics, Applied Mathematics and Humanities;
the latter, formed almost 40 years ago under
Dr. Joseph Vaughan, is unusual and will be men-
tioned again. Applied Mathematics now includes
Computer Science, and within the last five years
has become a degree-granting department offer-
ing first a graduate and now also an undergrad-
uate program.
The Engineering School has been conspicu-
ously successful in promoting cooperation be-
tween departments, in teaching courses and in
interdisciplinary research. This appears to be
due somewhat to our moderate size, but it prob-
ably results also from the close relationship and
good technical awareness that exists between
many of our staff and among most departments.
Inter-school cooperation, with Medicine, Archi-
tecture, and the College of Arts and Sciences has
also been good.
Bachelor degrees have been awarded in chemi-
cal engineering since 1913. In the early years

Joseph C. Elgin and Lauren B. Hitchcock taught
in the department. J. Henry Rushton became
chairman in 1937; first Virgil C. Williams and
then Darrell E. Mack was his associate. Dr.
Rushton was followed by Robert M. Hubbard in
1946. Early during Bob's chairmanship funds
for a new building were secured and an excep-
tionally functional facility with a floor area of
20,000 square feet was completed in 1950. Al-
though it was then commodious, we are now
making full use of this building; the remarkable
thing is that most of the space is being used for
the purpose for which it was originally intended!
Also under Dr. Hubbard's leadership the Chemi-
cal Engineering Department pioneered in grad-
uate study in the Engineering School introducing
a master's program in 1949 and doctoral work in
1956. When Bob Hubbard arrived he was the
department. Beginning with Otis L. Updike, who
also joined the department in 1946, Bob gradually
built a fine teaching staff. This has included
John W. Eldridge, who left in 1962 to become
Chairman of the Department of Chemical Engi-
neering at the University of Massachusetts, and
James H. Gary, now Chairman of Chemical and
Petroleum Refinery Engineering at the Colorado
School of Mines. In 1963, Bob Hubbard stepped
down and Vincent W. Uhl came from Drexel In-
stitute of Technology to assume the chairman-
The teaching interests of our present staff
of seven embrace the basic subject areas of chem-
ical engineering. Each member teaches graduate
and undergraduate courses, in addition to involve-
ment in graduate research. Newcomers to the
department are encouraged and aided in develop-
ing their own niche and specialty. Some inter-
action has developed in departmental research;
this is evidenced in joint direction of dissertation
research, both within and across departmental
lines. The staff all have contact with the indus-
trial scene, some from former employment, others
from consulting, or both.

Our aspiration for our undergraduate stu-
dents has been stated as "to develop competence
in attacking new engineering problems and in
securing optimum solutions to existing problems
in chemical and allied fields. This competence is
based on a sound understanding of fundamentals,
on familiarity with experimental methods, on
general engineering background, and on the de-


veloped power to marshal these elements with
proficiency to handle problems, many of which
are quite complex". We feel that these goals
are largely realized by a bachelor's program
within the span of four or five years.* The in-
gredients supporting this accomplishment are our
faculty, the quality and attitude of our students,
and the resources-several of which are unique-
of the School of Engineering and Applied Science.
Our undergraduate curriculum happens to
correspond closely in subject weighting to the
current survey average in Barker's report**,
with the exception of our greater emphasis on
humanities (Table I).

TABLE I. Distribution of Subject Areas for CHE
ChE Curricula
Barker's Avg. Univ. of Va.
Communicative skills 5.0 6
Humanities 18.3 21

Subtotal 23.3 27
Mathematics 16.7 16
Chemistry 23.8 26
Physics 9.7 10

Electrical Engineering

Chemical Eng. (required)
Chemical Eng. (elective)
Technical Electives

Total semester credit hrs.




One of the unique aspects of our curriculum
is a program of four courses, two in the first and
two in the last year, taught by our Division of
the Humanities. This program is based upon an
interaction of many disciplines, and is intended
to challenge the student to face the modern world

*A five-year program is optional. The student may
be enrolled for a minimum of 15 credit hours each semes-
ter; more humanities and technical electives are taken.
**Barker, D. H., "Reduction in Hours and Introduction
of Common Years into the Chemical Enineering Curri-
cula", Department of Chemical Engineering, Brigham
Young University, Provo, Utah. Report received July,

. . our students enjoy a high degree of
individual attention . .

from a broad perspective. It is roughly equival-
ent to two years of college English, but is faster-
paced and includes many areas beyond rhetoric
and literature. Articulation skills are cultivated
effectively in this program. In addition, five elec-
tive humanities courses are chosen to develop or
enhance knowledge in fields such as economics,
psychology, sociology, philosophy, history, relig-
ion, and literature. This elective program,
planned by the student with his advisor, generally
has two areas of emphasis.
Since 1965 the Engineering School has had a core pro-
gram, extended in 1970 to the first two years. These have
been some of the salient guidelines: a maximum of 17
or 18 credit hours per semester; a maximum of six or
if possible five required courses per semester; the elim-
ination of needless duplication of course material. First
year students are introduced to computer programming
in the BASIC language, which is then applied to the
solution of simple engineering problems followed by a
series of short engineering projects. Because of the
chemistry requirements of chemical engineering, some
exceptions are necessary in the second year from this
core curriculum. As part of this core program all stu-
dents take a minimum four of seven elective courses in
the engineering science: mechanics (3 courses), electrical
science (2 courses), thermodynamics, and science of
materials. All competent departments participate in the
planning and teaching of these core courses. Our depart-
ment participates in teaching the materials science, ther-
modynamics, computer programming, and engineering
problems courses. We have in fact taken a leadership
role in the formulation and direction of the core thermo-
dynamics course, and are proud of its thoroughness.
The physical operations are taught from the trans-
port viewpoint; in addition a weekly lecture, which is
part of the two-semester chemical engineering laboratory
course, emphasizes the relation of the transport theory
to experiment and practice. These lectures also introduce
new topics for which there are special laboratory exer-
cises. Some aspects of mass transfer operations will
now also be considered in a two-semester, third-year
course in Equilibrium Processes. This course will bring
together stoichiometry, thermodynamics, phase equilibria
and stagewise operations. Our conviction is that these
topics should be related for effective instruction. Back-
ground in industrial chemistry and plant practice is
provided by plant inspection trips and a seminar course
in the senior year. Here the students learn on their own
about some processes and each presents certain ones to
the class. The student gets practice in oral reporting
and learns how to become the expert on a topic. In pre-
paring for these talks the students are guided to and
required to use established library searching techniques.
Some (but admittedly limited) flexibility is provided
by three technical electives, two of which are taken in
a given field such as biomedical engineering, chemistry,


materials science, mathematics, or other areas of chemical
engineering. Such areas include equipment design for
which there is a course, based on extensive notes by
Dr. Hubbard plus selections from Perry. Another popu-
lar departmental elective is applied surface chemistry,
taught by Dr. John Gainer. It, along with the required
kinetics course, reflects the strong inclination of some of
the staff to emphasize applied chemistry to our students.
All seniors take reaction kinetics, process control, and
plant design. The process control course has a balance of
hardware emphasis with theory, and makes use of six
elaborate teaching aids, modules which demonstrate the
modes of control and the characteristics of different
devices used to sense and control temperature, flow, and
pressure. In the plant design course the elements of tech-
nical economics are emphasized, using material developed
by Dr. Uhl for his AIChE TODAY SERIES short
course. A process design is completed by students work-
ing in teams of three on one of the problems first de-
veloped by Washington University in cooperation with
Monsanto. Generally the seniors also attack the AIChE
Student Contest Problem on an individual basis.
We are particularly proud of our two undergraduate
laboratory courses, which have been a prime and con-
tinuing interest of Dr. Hubbard. Much of the apparatus
and equipment is specially designed or modified to facili-
tate instruction. Many pieces are transparent so that
the action can be visually observed. Some experiments
are on pilot scale units, relatively heavily instrumented,
some with quite sophisticated controls. Recently a pilot
plant was completed for the catalytic reaction of
methanol and steam to produce hydrogen and carbon
monoxide. The unit reaches steady state quickly, the
reactants are cheap and available, and the products are
disposable. This unit is already proving useful in pro-
viding a process experience and in generating raw
kinetic data for analysis. Perhaps the outstanding
feature of the laboratory is that the equipment works
smoothly and predictably.
Our students enjoy a high degree of individual
attention. This is feasible because our classes
are small and possible because our staff are gen-
erally on hand and interested. Only staff mem-
bers are used for lecture courses; graduate stu-
dents such as NDEA trainees, however, direct
problem sessions and occasionally run a section
of the laboratories. We are very conscious of, and
stress, good teaching. Classrooms in our building
are equipped with (or for) the usual teaching
aids and we use them, particularly the overhead
Between ten and twenty receive bachelor's
degrees in most years. A high proportion go
directly to industry. We are pleased with reports
which we receive about our recent graduates:
"immediately useful", "not bewildered by indus-
try", "know what is expected of them". About a
quarter of our students continue their education
in chemical or other branches of engineering.
Generally a couple of students from each class


continue in other fields such as graduate business,
law, or medicine.
Because of the varied teaching and research
interests of our faculty we consider we have
achieved a good balance, one in which our grad-
uate program effectively complements under-
graduate work.

The areas of interest and special research fields of
our staff members range broadly over almost the full
breadth of process engineering.
Dr. Charles Barron works primarily on problems
which involve the integration of chemical reaction theory
into the analysis of complex process systems.
Dr. Gainer's original research interest in liquid dif-
fusion, diffusion in polymer solutions and transport
through membranes has now been extended to mass trans-
fer in biological systems.
Dr. Robert Hubbard's research interests have been in
the fields of continuous ion exchange, extended surface
heat transfer, process dynamics and the measurement
and control of process variables.
Dr. Donald Kirwan, who recently joined the faculty,
has research interests in the general field of unusual
separation techniques.
Dr. Lembit Lilleleht's interest lies primarily with
the fluid mechanics of multiphase systems.
Dr. Vincent Uhl has long had interests in mixing,
heat transfer and technical economics; his current re-
search is concerned with mechanically aided heat transfer.
Dr. Otis Updike has long been interested in computers
and their application to chemical engineering problems-
initially analog machines, later digital and hybrid.
Despite the breadth of research interest exhibited by
our faculty, the areas are effectively complementary, as
with process dynamics, fluid mechanics and mass trans-
fer. Some research has involved collaborators from other
departments: nuclear engineering, mechanical engineer-
ing, materials science, biomedical engineering. We antici-
pate that this cooperation will grow, in particular in the
area of materials science with work on blood clotting.
About one-third of the present research is concerned with
life processes: the development of blood-mimic fluids,
blood flow modeling, diffusion studies in biological fluids,
reactions related to the absorption of oxygen in the lungs,
enzyme kinetics and protein separation methods.


In recent years we have built an active com-
munity of graduate students which numbers more
than twenty, over half of whom are engaged in
doctoral work. We very seldom keep our own
undergraduates; because we are convinced that
students benefit greatly from a change of scene,
we insist that they go elsewhere to continue their
studies. While we welcome students from other
countries, we strive for diversity and balance.
Foreign student enrollment is now about 30 per-
cent of the total. We currently graduate about

Our aspiration for our undergraduate students: to develop competence in attacking new engineering
problems and in securing optimum solutions to existing problems in chemical and allied fields.

eight masters and four doctoral students each
Almost all graduate students are supported
financially by fellowships which allow them to
devote full time to study and research, or on
assistantships for research only. In addition to
the usual sources of support such as NSF Fellow-
ships, NDEA Traineeships, industrial fellowships
and research grants, we receive a substantial sum
each year from the bequest of Christopher Mem-
minger which supports several students each year
and departmental research. Mr. Christopher
Memminger, the donor, was a graduate of the
University of Virginia and founder of the Cor-
onet Phosphate Company.
Our entering masters students normally take
courses in fluid mechanics, thermodynamics, re-
action kinetics, three elective courses and two
courses in mathematics, one of which may be the
applied mathematics course taught in the depart-
ment. Heat transfer courses are taught by mem-
bers of the Mechanical Engineering, Nuclear En-
gineering or Chemical Engineering Departments.
Although a non-thesis master's program is on the
books for engineering, we usually require a thesis
for chemical engineering students. We encourage
students to complete work for the masters within
twelve months and this has been possible in most
Our doctoral program has a traditional em-
phasis, except for the interdisciplinary atmos-
phere. A requirement of special interest is selec-
tion and development of a proposition in an area
different from that of the dissertation to demon-
strate ability to do original work. This must be
completed in a month, and students are then
orally examined on their reported solutions as
well as on their general knowledge; this consti-
tutes their comprehensive examination as doc-
toral candidates. Reading proficiency is required
in one foreign language.
We also work with our graduate students to
cultivate the ability to organize and present tech-
nical matter effectively. Each student speaks
several times at our graduate seminars and we
encourage them to speak at local and national
meetings when practical. We want our graduates
to be articulate.

The department has been continuously aware

of the educational needs of the chemical engi-
neers in the many chemical and process indus-
tries in Virginia. For several years we have
offered a part-time graduate program; by now
this has served the needs of a number of chemical
engineers working in nearby plants. To be of
broader service, beginning in 1968, we have
offered about three short courses each year; each
staff member has developed a course in one of
his specialties. These have had the extra advan-
tage of increasing our awareness of the problems
of industry and improving our contacts with
working engineers. It is a program which we
hope to continue.
For the future, we expect to continue offering
a four-year undergraduate program based on a
strong background in chemistry (as well as
physics and mathematics) in which the student
will gain adequate proficiency with analysis,
synthesis (from process design), and computa-
tion, and cultivate one or more humanistic areas.
Research will probably become still more inter-
disciplinary in character and will grow in its
emphasis of living processes. To balance the
theory, the graduate program, at least for some
students, will continue to emphasize practical
What are some of the marks of our depart-
ment? Diversity of research interests. Collabora-
tion in research. Research concerned with life
processes. Balance between undergraduate and
graduate programs. Concern about good teach-
ing. For the undergraduate: stress on funda-
mentals; sound chemistry background; develop-
ment of computational prowess; excellent labora-
tory experiences; promotion of some feel for the
practice of engineering. For graduate students:
programs with traditional research emphasis;
development of creativity, analytical ability, and
articulation; conversancy with fundamentals;
the power to apply knowledge to practice. In
this we feel we are fulfilling this dictum of our
"A University on a plan so broad and liberal and modern
as to be worth patronizing with the public support, and to
be a temptation to the youth of other states to come and
drink of the cup of knowledge and fraternize with us."-
T. Jefferson



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synthetic fuels. Or making our ocean water
drinkable. Or developing high efficiency
nuclear cells to keep the lights on in the year
2000. The challenge of making a barrel of
crude oil work harder to conserve our
fossil fuel resources.
And these are only a few of the challenges
at Gulf. Meeting them requires top graduates
in every technical, scientific, managerial,
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If you're the type person who likes to
provide answers to make ours a better
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with Gulf. For additional information, write
Virgil Hanson, Gulf Oil Corporation,
P. O. Drawer 2100, Houston, Texas 77001.



This feature article was prepared for CEE by
Professor John C. Biery, University of Arizona.



Chemical engineering to Alan Randolph is a
profession which requires a balanced synthesis of
experimental and theoretical programs. His own
research in particulate systems and his profes-
sional career are outstanding examples of this
view. He feels very strongly about maintaining
this balance between theory and experiment for
the profession. He says, "Chemical engineering
must achieve this balance; otherwise, an ever
increasing split within the ranks of chemical en-
gineers will occur. This growing schism, which,
unfortunately and unnecessarily, often pits aca-
demician versus industrial technologist, is readily
observable at our national AIChE meetings."

At the University of Arizona, Alan has devel-
oped a program which contains strong elements
of experiment and mathematical theory in his
study of particle dynamics in crystallization and
grinding. For instance, he has two students who
have mathematically simulated these two types
of particulate processes in a total system simula-

Alan with son David
on Mt. Lemmon ski slope
near Tucson. 'Skiing is a
sometime-thing but you just
keep hoping."

tion using population balance models. Comple-
mentary to this program, two other students have
experimentally studied crystal nucleation kinetics
in a bench-scale crystallizer well-suited for simi-
lar industrial studies and more fundamental nu-
cleation mechanisms in realistic crystallization
environments by using very sophisticated auto-
matic particle counting techniques representing
the current state-of-the-art. Each of these experi-
mental and theoretical programs has assisted the
other. The experimental programs are designed
to seek basic mechanisms while the simulation
programs indicate the mechanisms that are re-
quired to predict behavior in large commercial
systems that cannot be studied experimentally.
Alan's career has been purposely directed
toward the welding of these two elements of
Chemical Engineering. After graduating from

Alan's involvement in the overall chemical engineering
by the following profiles by two of his graduate stuc

"Alan Randolph is a man engrossed in
the swirling, growing technology of crystallization. He
is smilingly thought of by his graduate students as a
generating source for new and innovating concepts which
originate from a scrap of paper signed ADR or preferably
from a coffee-stained napkin.
Each of his new students is properly initiated by a
formal introduction to Mr. Tuffy, Alan's least outspoken
graduate student. Mr. Tuffy is a three-foot wooden
Kachina make by San Juan Pueblo Indians and represents
Alan Randolph's often expressed love for the West. Alan
Randolph is truly admired for his dedication and inex-
haustible patience." Eric Nuttall

process on an exciting and interactive level is indicated

"Alan Randolph is in some ways similar to
the nucleating, growing crystals that he studies. He is
constantly generating new twists to old ideas and hav-
ing his graduate students check them out. Should the
graduate student generate a new idea, he must convince
Alan of its veracity and often finds him to be the roughest
critic. This process draws upon all the student's technical
and argumentative talents to produce a clear, concise
formulation of that idea. Alan continually admonishes
his students to consider the many facets of crystallization.
For example, during the winter months he doggedly tells
them to 'Think snow!' "-Mike Cise


Chemical engineering to Alan is a profession which requires a balanced synthesis of experimental and
theoretical programs. His own research in particulate systems and his professional career are
outstanding examples of this view.

the University of Colorado with a BS in 1956,
he worked for two years with Shell Chemical.
There he became involved with an ammonium
sulfate crystallizer that was having crystal-size
distribution (CSD) problems and was dynami-
cally unstable. This unstable behavior, poorly
understood at the time, was fascinating to him
and to others in the group.
In 1958, he entered Iowa State University and
obtained an MS and PhD by 1962. After complet-
ing an MS by studying entrainment in distilla-
tion, he decided that he wanted to study the types
of crystallization systems that he previously had
encountered, e.g. the system with unstable CSD
at Shell Chemical. To Dr. Mauri Larson he pro-
posed a program of study which was motivated
by an article by W. C. Saeman. This paper an-
alytically described the steady state CSD in a
single stage mixed crystallizer. Alan proposed
that he study the general dynamic problem of
crystal-size distribution using a population den-
sity function. In this PhD program, he success-
fully developed mathematical models to describe
the dynamics of CSD in such crystallization sys-
tems, and showed the process coupling that could
result in an unstable CSD. In addition, he quan-
titatively evaluated stability limits in terms of
system crystal growth and nucleation kinetics.
This PhD work resulted in development of a gen-
eral population balance for a dynamic mixed sus-
pension crystallizer with crystal-size distribution
characterized by the population density function.

His choice of jobs after leaving Iowa State
University indicated that he had developed a
sense of direction for his chemical engineering
career. Instead of accepting some very tempting
positions in groups involved with process control
and transport phenomena, he joined American
Potash and Chemical Company at Trona, Cali-
fornia (located in a rather remote region next
to Death Valley in California's Mojave desert).
Although Alan at first had some misgivings
about the location, he soon learned to love the
desert climate and surrounding terrain, and both
he and his wife remember the years at Trona as
some of the most enoyable of their life.
Alan's chief motivation in choosing the Trona

job opportunity was to try out his population bal-
ance models on some large-scale industrial crys-
tallizers. These models were successful and be-
came the basis for analyzing size distribution per-
formance for a multitude of crystallizer systems
at American Potash. Before leaving, Alan be-
came head of the crystallizer research section.
Also, while at American Potash, he realized
the population balance models that he was using
could be generalized. He published a generalized
population continuity equation in particle phase
space that could be useful for simulation of multi-
dimensional particle distributions in a variety
of systems, e.g. microbial, macromolecular, cata-
lyst suspension, demographic, etc. Almost simul-
taneously, Hulbert and Katz also published a
paper which developed a generalized particle bal-
ance continuity equation and thus confirmed the
generality of the population balance approach
first applied to the CSD problem.

To be able to study fundamentally problems in
particle systems and to teach others of his phi-
losophy concerning the balance between theory
and experiment, Alan accepted a faculty position
in the Chemical Engineering Department of the
University of Florida in 1965. His efforts were
directed toward understanding the fundamentals
of nucleation and growth in crystallization sys-
tems and their interaction with process configura-
tion to determine the CSD. Since then, both at

Alan and graduate student Mike Cise examine crystals used as
seed in nucleation apparatus.


A fine point in particle classification is discussed with graduate
student Eric Nuttall.
Florida and after 1968, at the University of
Arizona, he has expanded his interests in particle
systems to include grinding, biological and dis-
persed phase populations.
Alan has found that the two elements of
research, experimentation and theoretical formu-
lation, reinforce each other. One element for a
time will lead the other, and then their relative
positions will reverse. For instance, the theory
first indicates what particle dynamics phenomena
needs to be measured, e.g. nucleation and growth
rate kinetics, particle breakage, particle classi-
fication, etc. Experimental data are then ana-
lyzed using the general CSD theory to back-out
and correlate these empirical particle dynamics
functions. Then, with numerical values and/or
reasonable empiricisms representing such particle
kinetics, the mathematical theory is utilized in
overall computer simulations to predict the be-
havior of large complicated systems that cannot
be studied directly. In this phase, CSD theory
leads experimental kinetics and motivates further
refinement of experimental measurements.
From the previous discussion, Alan's involve-
ment in the academic world would appear to be
totally one of a researcher. Actually, he has
equally involved himself in teaching at both the
graduate and undergraduate levels. He teaches
such courses as transport phenomena, process
control, unit operations, process dynamics, and
a special topics course in particulate systems.
He has been able to bring to these the same bal-
ance that he has displayed in his research. In
his area of specialization, together with Dr.
Larson of Iowa State University, he has written
a book that can be used as a graduate text in
courses concerned with crystallization in particu-
lar and particulate processes in general.

. . no student should go through to the PhD
without the awareness of how theoretical models
are tested and their necessary relationship to
the real world.

This balance between experiment and theory
has amplified a similar balance in the Chemical
Engineering Department at the University of
Arizona. The department has concentrated on
teaching computational theory, methods, and
techniques by utilizing transport phenomena, unit
operations, process control, thermodynamics, etc.
The desired end result is a capability to design
chemical engineering processes and equipment,
and to analyze chemical engineering data to
understand a given process. The effective chemi-
cal engineer must have a sound grasp of theory
plus an appreciation of the experimental process
to gain these ends. In this regard, the faculty at
the U of A feels strongly that every PhD can-
didate should have some experience in the plan-
ning or execution of an experimental program at
least once during his graduate career. Such ex-
perience can come at the MS level or in gathering
and organizing experimental data taken by
others, e.g. data made available by an industrial
organization or in a previous experimental study
by another student. The U of A faculty's main
concern in this area is that no student go through
to the PhD without awareness of how theoretical
models are tested and their necessary relationship
to the real world.

LETTERS (con't from p. 57)
It is a well know thermodynamic principle that for a
single component, nonreacting, single phase, ideal gas
system in a state of quasi-equilibrium, that
d5 S,(T)dT (g)
where C (T) is the heat capacity at constant volume per unit mass.
Usually, 8C(T) = a + bT + CT2 + - -.
Combining equations (f) and (g) yields

dTt TV 1 _T_
mt (T) i-W7 j vif 8 i (M.W.) (h)
At this Juncture, it is possible to effect a simplification by
letting 6C(T) be a constant. Thus,
d Tt ^ wiRTi
tt = 5?t [aTi Tt + Tmih-7V) (i)
which is the same as equation (b) of Himmelblau and
Now the reoccuring error associated with problems
of this kind is simply the fact that C,(T) is and should
remain outside, not inside, of the time derivative term
(Continued on page 71)


Beneath this soft and warm exterior,

there lies a heart of plastic.

So tar, it's only a valve. Fight-year-old
Janet Hemandez has one.
It may not be long before a whole
working heart will be made out of plastic.
Men in plastics research at Union
Carbide are working on the almost im-
possible job of designing plastics com-
patible with the body.
Their most crucial job is making an
ultra-thin polypropylene fabric for lining
the inside of the heart. A fabric coated
with parylene that will allow human tis-
sue to grow into and around it to keep
blood from clotting.
A plastic heart isn't the only part of
the body we're working on. Maybe some-
day there will be a little plastic in all of us.
Right now, we've got you surrounded

fore most people knew the word. We
make more plastics than anyone else. We
haven't scratched the surface yet.
Why is a great big company like Union
Carbide so concerned about a little bit of
plastic for the body?
Beneath our corporate exterior, there
beats a heart.


For additional information on our activities, write to Union Carbide Corporation, 270 Park Avenue, New York, New York 10017. An equal opportunity employer.



Virginia Polytechnic Institute
Blacksburg, Virginia 24061

T HE PAST FEW YEARS have seen a marked
increase in the emphasis on effective teaching
and in attempts to understand and to regulate
the learning process. Amidst the hardware and
software of the effective teaching movement, the
lecture stands condemned. The cry goes out that
"the lecture is dead."
In its original setting, the lecture format made
sense. We can see the medieval scholar standing
at his lectern, sharing the fruits of his scholar-
ship, as contained in the handwritten manuscript
before him, with his students. But with the in-
vention of the printing press and all of the ad-
vances in communication which have taken place
in the meantime, should the lecture remain un-
changed? Materials are now readily available to
students. No longer are they dependent upon the
physical presence of the scholar. They can read
and study for themselves and interpretations of
the original documents are readily available.
Textbooks and study guides are produced by the
carload. "Modern teaching methods" and "mod-
ern technology" are here to assist the student.
Why then do we have the usual college lecture-
often merely a reading of the textbook to the stu-
dents-persisting ?

If the lecture is indeed dead, why not let it
die a peaceful death and then bury it? While this
paper does not propose to be a defense of the lec-
ture, I might offer a couple of reasons why the
lecture is bound to be around for quite a while
yet. If the lecture is to remain with us, then
spending time and effort to improve it can be
The lecture will continue to exist because the
present educational process is self-perpetuating.
The new engineering teachers are the products of
the old system and technical competence is still

*Presented at the 1970 ASEE meeting at Ohio State

9milosti~ Ihe .1eda~e

Despite being attacked as inefficient and out-
moded, the lecture continues to be the most com-
monly used format for teaching. This paper out-
lines some of the lessons learned in applying a
technique for improving the educational value of
the lecture by capitalizing upon the student's in-
volvement in note-taking.
Semi-notes do not represent a cure-all for
educational ills, but if they are used within their
limitations they represent a convenient method
of increasing lecture effectiveness. Little addition-
al effort on the part of the instructor is required
for their implementation.

deemed to be adequate preparation for college
level teaching. By and large, therefore, college
teachers will perpetuate the system under which
they were taught, because they know of no other.
Add to this the fact that classrooms and univer-
sity facilities have been planned around the lec-
ture approach. Throw in the fact that the lecture
is very efficient in the use of the instructor's time
-his involvement with the students in mini-
mized, freeing large amounts of his time for "the
more important things" which revolve around
technical matters. Stir these attitudes and pres-
sures together, and it becomes evident that the
lecture is firmly entrenched and will not die
Another reason for the continued existence of
the lecture revolves around the fact that the lec-
ture approach is the one with which the students
are familiar and the one with which they feel
comfortable. Throughout their school years they
have been conditioned to believe that learning is
something that occurs in a classroom in the pres-
ence of someone called a teacher. If the teacher
does not show up one day, then that day is lost.
Nothing can be learned. Even at the graduate
level, where we are dealing with very capable and
highly motivated students, this attitude is readily
apparent. Try an experiment. Delay your arrival
in the classroom for fifteen or twenty minutes.
How often will you enter the room to join a dis-
cussion of the topic of the day? More than likely
you will find the students (if any have waited


Roland A. Mischke received his undergraduate degree
from Pratt Institute (B.Ch.E. '50) and worked for six
years as a design engineer with Chemical Construction
Corporation before returning to graduate school. Follow-
ing the completion of his graduate studies (Ph.D North-
western '61) he entered the teaching profession. He is
currently in his ninth year at Virginia Polytechnic Insti-
tute and State University, where he has been involved in
the teaching and direction of research in the fields of
reaction kinetics, fluid dynamics, thermodynamics and
heat transfer. In addition to his teaching responsibilities
in the Chemical Engineering Department, he is also Edu-
cational Technology Coordinator for the College of

around) chatting together and waiting for the
"show" to begin. The possibility of learning
something in the absence of the instructor never
occurred to them-that thought is completely
foreign to their upbringing. The lecture, then,
has two things going for it. The students want it
and the teachers want it.
A third reason for not burying the lecture ap-
proach is that we know too little of the learning
process to completely dismiss the lecture. Modern
approaches to teaching are becoming available in
the form of programmed instruction, computer-
aided instruction, television (closed circuit and
tape), audio-tutorial methods, etc., but we have
only incomplete evaluations of the ultimate worth
of these methods. Certainly many of these meth-
ods are more effective than the lecture in the
transmission of facts. But a lecture transmits
more than facts. Studying a book with a teacher
is more satisfying and more rewarding than
studying the book alone. Something else comes
across along with the factual information. Simply
equating education with factual knowledge could
be dangerous. Such a comparison ignores the
higher levels of the cognitive skills described by
Bloom (1)-those of analysis, systhesis and evalu-
ation. The sign which hangs in my office to remind

me of my job as a teacher says "Education is
what is left over after you have forgotten the
facts." Education and learning are more than ab-
sorbing facts and storing them away as a com-
puter does-to be retrieved and used mechanically
upon demand.
The stimulus-response approaches and even
the modern day "systems" approaches tend to
treat the student as an automaton or mechanism.
The basic premise seems to be that a certain
stimulus should produce a very predictable re-
sponse, and much testing and evaluation of teach-
ing methods is done on just such a basis. How-
ever, if we accept the concept (von Karman) that
"an engineer creates what never was," then crea-
tivity-the unique response to a stimulus-is
what we need to develop and not stifle. Engineers
trained in the traditional manner have been
showing some creativity, and until we know more
about how to effectively teach creativity and the
higher cognitive skills, we should be careful about
condemning the lecture.
Whether we like it or not, good or bad, the
lecture is going to be around for some time. The
lecture may be dead, but there is no reason for it
to be deadly.


T HE ATTENTION SPAN of a listening adult
is just about two minutes. That is, we can have
a person's undivided attention for only about two
minutes. If we fail to interest him (show the rele-
vance of the topic to his needs) in that period of
time, then his attention will wander. Therefore, a
lecture must involve a student (either mentally or
physically) at least once every two minutes if
we want to maintain his attention. The usual
techniques suggested for effective speaking make
use of just such planned involvements of the
listener, but we can capitalize on something else
in a classroom situation.
Working in our favor is the fact that a stu-
dent in a classroom is involved in one way in
which the usual listener is not-the student is
busy taking notes. Looking back over some of
the notes that I took in college, I find them to be
a pretty disorganized mess. Most of them are un-
decipherable now (and thinking back over my
attempts to review for tests, I'm not so sure that
they were decipherable even back then.) Glancing
at the notebooks kept by students today I find
much the same situation. If we stop to consider
just what is required of the student in producing


The lecture will continue to exist because: the present educational process is self-perpetuating; both the stu-
dents and the teacher want it; we know too little of the learning process to completely dismiss it.

a coherent set of notes, it is no wonder that the
results are what they are. A student must listen
to material (much of which is new to him), try
to follow the logic of the presentation, make value
judgments on this logic, sort out the relevant
points and organize them into a legible and co-
herent style. Certainly a formidable task.
Some years ago Zumwalt (2) presented the
concept of semi-notes or incomplete notes as an
aid to student learning. In this approach the stu-
dent is presented with the skeleton of a set of
notes, and he completes the picture by the ad-
dition of his own notes and comments during the
course of the lecture.
I have used semi-notes in several chemical
engineering courses over the past couple of years,
and I would like to share with you my impres-
sions of the advantages and disadvantages of
this approach.


From the student's point of view, these notes
come as a godsend. For once he can concentrate
on what is being said rather than spending a good
deal of his effort in organizing a set of notes.
At the end of the course, regardless of his ability
as a note-taker, he has:

1. ACCURATE NOTES. It is sometimes surprising
to see how often errors creep into student notes (this
in spite of the sterling and crystal clear presentations
that we make.) Having a roadmap to follow helps to
keep them on the right track, and the distractions from
such things as passing trucks, noisy lawnmowers, etc.
seem to produce fewer errors when semi-notes are
2. ORGANIZED NOTES. The notes are coherent and
organized around a logical development. This aspect is
important when the time for review comes around.
3. PERSONALIZED NOTES. Although the skeleton
or framework is supplied, much of the material in the
completed notes is in the student's own handwriting.
He has also had the opportunity to make special notes
and markings which will help him to interpret the
notes later on.
4. SIGNIFICANT NOTES. Not only are the notes
coherent, they also contain what the instructor con-
siders important. This is a definite plus value for the


From the instructor's point of view, the use

of semi-notes represents an additional burden.
The instructor must cope with:

1. PREPARATION OF NOTES. The notes must be
prepared and be ready for distribution to the students
before the lecture is given. Fortunately, the work that
is involved in preparing these notes is not much more
than that required to prepare a fairly complete set of
notes for lecturing. I ha;e found that by writing in
pencil on a Ditto master, the master is prepared for
duplication and a projection transparency can easily
be Thermofaxed if one is desired.
2. RIGIDITY OF STYLE. When following the notes,
the lecture presentation is not as free-flowing as it
could be. The instructor cannot easily deviate from
the pre-determined order of presentation. Perhaps the
most frustrating thing I have encountered here is a
lack of freedom in the choice of words. The words
suggested to fill in the blank spaces in the notes must
generally be very close to those in mind when the
notes were prepared. If a better way to say something
occurs to the instructor in the midst of his presenta-
tion, not only must it make sense when coupled with
what appears on the handout sheet, it must also fit
into the space provided. One soon learns to be care-
ful to consider alternate ways of saying things during
the initial preparation of the notes.


When considered from the pedagogical point
of view, semi-notes have strong and weak points.
These include:

aspect probably accounts for one of the largest im-
pacts that the use of the notes can provide on the
improvement of the lecture. THE INSTRUCTOR
cuff lectures can be made. The lectures become organ-
ized, not only within themselves, but between lectures
also, because that is the way that they must be under
this system.
dents must be awake and involved in order to com-
plete the notes. By supplying the connecting thoughts
and having the student write in the key thoughts, con-
siderable reinforcement of these key thoughts is pro-
vided for the student (he is involved in hearing, seeing
and doing-all at the same time.)
Because the semi-notes represent the "distilled essence
of knowledge" for the course, students will tend to
ignore the textbook and await the next "revelation"
unless they are forced to interpret the textbook by
some sore of assignment which requires a study of the


LOGICAL SET." By just following the organization
and development of a topic rather than being involved
in such a formulation, they may get into the habit of
saying yes ... that makes sense ... of course ... etc.
without really understanding the development. They
may say, "Yes, I see," when they don't really "see."
This process can lead to a false sense of security in the
student-and potential disaster at exam time.


Like most things, semi-notes turn out to be a
mixed blessing. With careful use and an aware-
ness of their shortcomings they can be a very
useful tool in teaching. The main advantages stem
from the fact that:

* The instructor must organize his presentation.
* The students must become involved with the
* The students like the notes and appreciate

The major disadvantages of semi-notes seems
to lie in presenting to the student a well-organ-
ized and seemingly simple explanation. If the
student accepts the logic unquestioningly, he may
learn little. Learning is an intensely personal ex-
perience-the result of a struggle of each indi-
vidual with himself, and a special effort must be
made to get the student involved in that struggle,
thereby making the notes as effective as possible.
The role of the teacher is often likened to that
of a guide. But what person would pay good
money to hire a hunting guide who invariably
said, "Come and watch me hunt." A person who
hires a guide wants that guide to take him to
where the game may be found, to give him some
pointers on technique, but not to down the game
for him.
Here, then, is the challenge of effective use
of semi-notes: to lead the student to and through
the subject and not cheat him of the fun of bag-
ging the game himself. Semi-notes will work. They
will work well within the framework of the exist-
ing lecture format. The challenge is to keep them
working for the student and not to let them
work against the best interests of his education.


1. Bloom, B. "Taxonomy of Educational Objectives: Cog-
nitive Domain," McKay, New York, 1963.
2. Zumwalt, G. W. "SEMI NOTES: An Aid for the En-
gineering Lecture," Journal of Engineering Educa-
tion, 54(5), 182 (1964).

The following picture and biographies, recently
received, are of the authors of "A Facility for
Education in Real-Time Computing" CEE, 5,
No. 1, p. 30-32 (1971).
James H. Christensen (right) is Assistant Professor
of Chemical Engineering, and of Information and Com-
puting Science, at the University of Oklahoma. He re-
ceived his PhD in Chemical Engineering from the Uni-
versity of Wisconsin in 1967, and was a Ford Founda-
tion Fellow in Engineering Design at Thayer School of
Engineering at Dartmouth prior to moving to Oklahoma
in July 1968. His main interests are in the application
of digital computers to chemical process design, optimiza-
tion, and control.
Paul M. Vargo (left) received his PhD from Case-
Western Reserve University in 1969. During the last
2 years, while a faculty member of the Electrical Engi-
neering School, University of Oklahoma, his activities
have included developing a Real-Time Computer System
to support education and research activities and initiat-
ing a research project exploring Man-Computer Com-

(Cont'd from p. 66)
in equation (h) even if it is a variable. One usually
sees various authors attempt to write, incorrectly, the

d using reference temperatures and other gimmicks. The
right-hand-side of equation (j) correctly accounts for
unsteady-state internal energy changes but the left-hand-
side is pure nonsense. To the unitiated, the l.h.s. of
equation (j) is, indeed, tempting.
The stirred-tank, energy design equations on page
4-23 of Perry's Handbook, 4th Ed. are in error.
Burton Davidson
Rutgers University





University of Pennsylvania
Philadelphia, Pa. 19104
I National Bureau of Standards and Bell Tele-
phone Laboratories in a single organization called
the U. S. Academy of Sciences. This hypothetical
research conglomerate would be comparable to
the Soviet Academy of Sciences. Our visit, for
five months of research at the Institute of Physi-
cal Chemistry of the Soviet Academy of Sciences
in Moscow, gave us an opportunity to observe
from the inside the working order of the Russian
scientific establishment.
Our plane landed at the Moscow International
Airport on a dreary Monday evening last year.
We had heard dismal stories about the experi-
ences of others and our excitement was dampened
as much by uncertainty as by the rain.
Prepared for a long wait and complicated
customs procedures, we were pleased to claim
our unopened baggage immediately. Exchange
scholars on the US-USSR Academies of Sciences
Program are practically free of political inter-
ference. The reason is that the Russians have the
same selfish motives that we have for keeping
open the lines of scientific communication. Within
an hour we checked into our new home for the
autumn and winter: the 14-story hotel of the
Academy of Sciences on Leninsky Prospect near
Gorky Park. The apartment, small but well-fur-
nished, had two rooms and a bathroom but no
kitchen. Luckily we had packed an electric skillet
which became the nucleus of a makeshift kitchen.
Borrowing an idea from the Russian housewife,
we used the interior of the double window for a
refrigerator. Nature did its best to keep the tem-
perature below freezing but occasionally we found
in our icebox an unexpected supply of defrosted
food. The bathtub turned out to be an all-purpose
fixture, serving as laundry tub, bathtub and
kitchen sink.
Our Russian colleagues at the Institute of
Physical Chemistry loaned us kitchenware and

small appliances and gave us useful shopping
tips. Still, for an American woman speaking little
Russian, shopping in Moscow was a full-time
job. Sign language and a sense of humor helped.
More often than not, curious shoppers joined in
to guess what the needed item might be. Usually
these guessing games ended in laughter and a
successful purchase. The Russian people are like
Americans, friendly and willing to help. Strang-
ers gave us their seats on buses for our children
and often showed concern about our children's
clothing. Russian housewives were astonished to
see our daughters dressed in a single coat for
the cold winter days. In Moscow, woolen or nylon
clothing articles are rare and the children wear
three or four layers of clothing to keep warm.
The streets of Moscow are literally lined with
buses, streetcars and minibuses. The fare is 3
to 5 kopecks (100 kopecks = 1 rouble) and the
passengers pay on the honor system by dropping
their fare into a machine and dialing their own
receipt. The fine for not paying is low, only 40
kopecks, so there is often someone trying to get
a free ride.
Stores in Moscow are specialized: bread stores,
dairy-product markets and vegetable stores but
only a few supermarkets. The stores are well-
stocked with staple items such a flour and sugar
but few luxury items or out-of-season fruits are
available. We quickly grew accustomed to stand-
ing in line. A single purchase is a complicated
transaction consisting of three steps: 1) find the
article and obtain its price at the counter, 2) pay
for the article and get a receipt at the nearby
cashier's desk and 3) return to the counter and
exchange the receipt for the article. This in-
efficiency is not amusing when you are in a hurry
to buy a loaf of bread.
Books are the best shopping bargain in Mos-
cow. The quality of the paper and the printing is
substandard but prices are very low. For ex-
ample, we purchased a hardbound copy of a popu-
lar course in physical chemistry (600 pages) for
$1.50. Comparable bargains are available in


Alan L. Myers graduated from the University of Cin-
cinnati with a BSChE '60. In 1964, he received his PhD
at the University of California at Berkeley. In 1964 he
joined the School of Chemical Engineering at the Univer-
sity of Pennsylvania. Alan Myers has consulted with the
Sun Oil Company and Atlantic-Richfield Company. His
research is in thermodynamics and surface chemistry.
His technical publications give the results of research
on adsorption from liquid mixtures, pulsed-adsorption
separation methods and sorption in molecular sieves. In
1969-1970 he was awarded a fellowship on the exchange
scientist program of the National Academy of Sciences.
fiction. The problem is that it is hard to find
copies of books by Bunin or Yevtyshenko, much
less Solzhenitsyn. The complete works of the
nineteenth century writers (Pushkin, Gogol,
etc.) are available in handsome and inexpensive
W E WERE OFTEN invited to Russian homes
where we became acquainted with the tradi-
tional Russian hospitality. No one we knew
owned a house; the apartments were small by
our standards. Often the grandparents share a
three-room flat with the young family. All of the
scientists and engineers whom we met own tele-
vision sets and refrigerators The Russians laugh
at our obsession about slimness. Food is not a
diversion in an evening of entertainment; it is
the main feature. Dinner lasts for hours and
hours and it is impossible to eat everything that
is served. The table totters under its load of
zakuski: cold meats, fish, salads, cheeses, breads
and sometimes caviar which, regretfully, is be-
coming scarce as pollution decimates the sturgeon
population of the Caspian Sea. These hours
d'oeuvres are delicious but, like a long-distance
runner, it is important to maintain restraint at
the beginning in order to finish. The next course
is borsch (cabbage and beet soup served with
sour cream) or another soup accompanied by
cabbage-filled cakes. Finally, almost too late to
enjoy it, the main course appears and is followed

leisurely by fresh fruit and assortments of cakes
and candy. Often, tea is served with a special
kind of jam which is eaten before each sip for
sweetening. Beverages with the meal include
Georgian wine, Armenian cognac and, of course,
We sampled the Moscow restaurants and
found the quality of the food and the service to
be occasionally very good but more often medi-
ocre. Tipping is considered somewhat belittling
and does not improve the service.
A typical wage in Moscow is 130 roubles (144
dollars at the official exchange rate) per month.
Usually husband and wife both work so that the
family earns 260 roubles per month. Russian
women, with equal pay, drive steamrollers, shovel
hot asphalt and are employed as doctors, scien-
tists and directors of collective farms.
A few weeks after we arrived in Moscow, we
enrolled our children in the State-run detsky sad
or kindergarten. The long school day, from 8:30
to 5, allows the Russian mother to work. Younger
children of working mothers attend the detsky
yasli or nursery schools. Our children's class of
twenty was cared for by four women. The daily
schedule included three meals and a long play
period or walk outside, even in the winter. A
three-hour nap (yes, three hours) ensures that
the children are full of energy when they return
home in the late afternoon.
T HERE ARE TEN years of school; Russian
children enter elementary school one year
later and finish high school one year earlier than
American children. More time is devoted to
physics, mathematics and chemistry in the Rus-
sian schools and, in Moscow, over half of the
children study English. For Russian teenagers

Moscow State University has an enrollment of 30,000 and is Russia's
finest university.


The primary function of Russian universities
is teaching . the basic research and
development is performed by the institutes
of the Soviet Academy of Sciences.

the heavy homework assignments provide little
spare time for dating and amusements. Even
though Russians love, almost idolize, their chil-
dren, they believe in strict discipline and the no-
nonsense approach that parents-know-best-
what's-good-for-their-children. The family life
is close and the generation gap is not taken very
The strength of the Soviet curricula in the
basic sciences has been well-known since the
launching of the first sputnik. Less well-known
is the Soviet emphasis upon foreign languages,
particularly English. The training begins early,
especially for the children of scientists. For ex-
ample, in 1958, when scientists and engineers
began to arrive in Novosibirsk to start the now-
famous scientific center in Siberia, one of their
first acts was the formation of an English reading
circle for their children. Programs like these
have achieved impressive results: a large per-
centage of Russian scientists and engineers speak
English and nearly all of them can read technical
Higher education in the USSR is divided into
two basic types: 1) universities and 2) special
educational institutions. The special educational
institutions have programs in agriculture, medi-
cine, pedagogy, etc. and include the technical
institutes which train the Russian engineers. The
duration of the engineering program is five years.
The engineering curricula at the technical insti-
tutes contain almost no courses in the humanities
and social sciences and there are no elective
courses. As a result, the Russian engineer re-
ceives a good but specialized technical education.
The Russians complain that their engineers do
not receive enough practical experience in the
laboratory, a complaint familiar to U. S. educa-
After obtaining a degree at a technical in-
stitute or at a university, the student, called an
aspirant, may work for the degree of Candidate
of Science. There is no formal course work for
the Candidate degree, which is based upon re-
search and requires the defense of a thesis. The
highest degree is Doctor of Science. It is tempt-
ing to equate the Russian degrees of Candidate
and Doctor with the U. S. degrees of MS and PhD
in the sciences. Actually the Russian degree of

Smolensky Cathedral in Moscow's Novodevichy Convent. In the con-
vent cemetery are the graves of the composer Scriabin and the
writers Gogol and Chekhov.

Doctor of Science requires much more work than
our PhD degree. For the Soviet doctorate, a
typical thesis is based upon a five- or ten-year
research program and dozens of publications.
The primary function of Russian universities
is teaching. Most of the basic research and de-
velopment is performed by the institutes of the
Soviet Academy of Sciences. This division of
teaching and research in the Soviet system con-
trasts sharply with the U. S. system, where most
basic research is done at the universities.
The research activities of the Soviet Academy
of Sciences are organized according to disciplines:
Institute of Organic Chemistry, Institute of
Mathematics, Institute of Geophysics, Institute of
Physical Chemistry, etc. Within each institute
authority is delegated to senior scientists called
academicians, who run research teams consisting
of several dozen scientists and technicians. The
rank of academician in the Soviet Union is a
cherished position which brings with it such
privileges as a chauffeur-driven car and virtually
unrestricted freedom to travel abroad.
The institutes in Moscow are quite crowded;
three scientists may share a small room. Only
academicians have private offices. Therefore it
was obviously no small sacrifice that I was given
a well-equipped private office. Dozens of Russian
scientists and engineers at the Institute of Physi-
cal chemistry work in the field of surface chemis-


St. Basil's Cathedral in Moscow, built during the reign of Tsar Ivan
the Terrible, has domes that resemble peppermint-striped onion bulbs.

try and the desire to learn about their research
was the reason for our trip to Moscow. Technical
discussions, sometimes in Russian and sometimes
in English, began a few days after our arrival.
Soon, the routine of daily discussions led to some
exchanges of ideas which were eventually pub.
lished in joint articles.
Besides the lack of space, Russian scientists
and engineers are faced with a scarcity of instru-
mentation and computing facilities. A Russian
scientist needing, say, a chromatograph for a
routine analysis may have to build it himself.
The computers (for example, the BESM 8) are
comparable in speed and storage capacity to the
latest American models but scientists complain
that the demand for computer time greatly ex-
ceeds the supply.
The most conspicuous weakness of the Soviet
scientific establishment is its technology. I heard
a lecture about the U.S. given by a Soviet scien-
tist, who said that the U. S. and Russia are equal
in strength of basic research but American tech-
nology is superior. He meant that the interlock-

ing and overlapping system of research and de-
velopment at U. S. universities and industrial
research laboratories has no counterpart in
Russia. In Russia, the universities teach, the In-
stitutes of the Academy of Sciences do basic re-
search and the industrial organizations do applied
research. This clear-cut division of responsibility
has obstructed the free exchange of ideas between
basic research and applied technology. The Rus-
sians are aware of this weakness and are experi-
menting now with plans for a more equitable
distribution of basic research among the institu-
tes, universities and industrial research labora-
Our trip to Russia was a rich and rewarding
experience. The exchange program sponsored by
the U. S. National Academy of Sciences has
accomplished the nearly impossible feat of open-
ing the lines of communication between the U. S.
and USSR. Unfortunately the number of scien-
tists and engineers exchanged each year is small
and it is hoped that agreements negotiated in the
future lead to a generous enlargement of the

The Kremlin Palace surrounded by the walls and towers of the
ancient Kremlin.

p news

The Relations with Industry Division of ASEE held
the 22nd Annual College-Industry Conference at the
University of Florida, Gainesville, Florida on February
5-6, 1970. The presentations at that conference are pub-
lished as Industry-Engineering Education Series 1-3,
The Current Campus Scene. Copies of this 77-page
paperback are $2.00. The booklet contains 13 papers
on the problems of the campus, the college-industry rela-
tionship, the student adjustment in industry and in gov-

ernment, the response of industry, and challenges to
higher education.
The Engineering School Libraries Division of ASEE
has published a Guide to Literature on Chemical Engi-
neering by V. E. Yagello, Head of Chemistry and Physics
Libraries, The Ohio State University. Single copies of
the 24 page guide are $1.00 but 250 if 10 or more are
This literature should be ordered from: Publication
Sales, ASEE, Suite 400, One Dupont Circle, Washington,
D. C. 20036.




The Wdlokuwi companUie hae dana/ed

.jau jk Me eap 4pot 4 CHEMICAL ENGINEERING EDUCATION dutin 1f971:





DEPARTMENTAL SPONSORS: h jolkowinf 133 depadmeUnteha

cnAdt d to &ke a"ppol, o4 CHEMICAL ENGINEERING EDUCATION in 1971

University of Akron
University of Alabama
University of Alberta
Arizona State University
University of Arizona
University of Arkansas
Auburn University
Brigham Young University
University of British Columbia
Bucknell University
University of Calgary
University of California, Berkeley
University of California, Davis
University of California, Santa Barbara
California Institute of Technology
Cambridge University, England
Carnegie-Mellon University
Case Western Reserve University
University of Cincinnati
Clarkson College of Technology
Clemson University
Cleveland State University
University of Colorado
Colorado School of Mines
Columbia University
University of Connecticut
Cooper Union
Cornell University
University of Delaware
University of Denver
University of Detroit
Drexel Institute of Technology
Ecole Polytech, Canada
Ecole Polytechnique, Switzerland
University of Florida
Georgia Institute of Technology
W. W. Holding Institute
University of Houston
Howard University
University of Idaho
University of Illinois, Chicago Circle
Illinois Institute of Technology
Iowa State University
University of Iowa

University of Kansas
Kansas State University
University of Kentucky
Lafayette College
Lamar State College of Technology
Laval University
University of Leeds
Lehigh University
Loughborough University of Technology
Louisiana Polytechnic Institute
Louisiana State University
University of Louisville
McGill University
McMaster University
University of Maine
Manhattan College
University of Maryland
University of Massachusetts
Massachusetts Institute of Technology
University of Michigan
Michigan State University
Michigan Technological University
University of Minnesota
University of Mississippi
University of Missouri, Columbia
University of Missouri, Rolla
Montana State University
University of Nebraska
Newark College of Engineering
City University of New York
University of New Mexico
New Mexico State University
University of New Brunswick
University of New Hampshire
North Carolina State University
University of North Dakota
Northwestern University
University of Notre Dame
Nova Scotia Technical College
Ohio University
Ohio State University
University of Oklahoma
Oklahoma State University
Oregon State University

University of Ottawa
University of Pennsylvania
Pennsylvania State University
University of Pittsburgh
Polytechnic Institute of Brooklyn
Princeton University
University of Puerto Rico
Purdue University
University of Quebec
Queen's University
Rensselaer Polytechnic Institute
University of Rhode Island
Rice University
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University of Saskatchewan
South Dakota School of Mines
University of Southern California
State University of N. Y. at Buffalo
University of Tennessee
University of Texas
Texas A & I University
Texas A & M University
Texas Technical University
University of Toledo
University of Toronto
Tufts University
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Tri-State College
Technion, Israel
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Virginia Polytechnic Institute
Wayne State University
University of Washington
University of Waterloo
University of Western Ontario
West Virginia Institute of Technology
West Virginia University
University of Wisconsin
Worcester Polytechnic Institute
University of Wyoming
Yale University
University of Windsor



The annual ASEE meeting will be held June
21-25, 1971 at U.S. Naval Academy, Annapolis,
Md. The ChE Program Chairman for the meeting
is Professor R. V. Jelinek, Syracuse University,
Syracuse, N.Y. 13210. The ChE Division program

12:00-Business Luncheon, Executive Committee
1:45-Workshop/Demonstration, W. D. Seider,
Computer Aids for ChE Education

10:00-Annual Lectureship Award
12:30-Division Business Meeting
1:45-Symposium/Conference, D. K. Anderson,
Recruiting High School Students into ChE

Speakers: Lloyd Berg; M. C. Hawley; W. R.
Kube; R. S. Schechter
6.30-Annual Division Banquet

8:00-Panel Discussion, A. E. Humphrey, presiding.
Departmental Administration
Panel: "How to Put Bioengineering into a ChE
Curriculum," K. B. Bischoff and R. L. Dedrick
Panel: "Guiding ChE Departments in Times of
Reduced National Funding," W. R. Marshall
and L. G. Mayfield.
10:00-Symposium, George Burnet, Chairman
Chemical Engineering Technology Education
"Associate Degree ChE Technology Program,"
John Kushner.
"Baccalaureate Degree ChE Technology Pro-
grams," Jesse DeFore.
"Peaceful Coexistence of Engineering and Tech-
nology in the University," M. A. Larson and
R. C. Seagrave.
Discussion led by panel of four speakers.

from the STAFF
You will be pleased to learn that, due to the efforts
of Professor Stuart Churchill of the University of Penn-
sylvania, a total of 133 departments of chemical engineer-
ing have contributed to the support of CEE in 1971-as
compared to 126 in 1970 and about one hundred in 1969. It
is also gratifying to note that a large number of depart-
ments have increased sizably the number of bulk subscrip-
tions that they have ordered. In addition, Professor John
Myers at Santa Barbara and Ed Bartkus at Du Pont have
been quite successful in obtaining additional subscriptions
from university and industrial libraries. Hence our sub-
scription income for 1971 should be appreciably greater
than in 1970. The editors and staff of CEE would like to
thank these people and the many departments who have
supported us with bulk subscriptions. If your department
has not contributed for 1971, you may still order bulk
subscriptions and receive back copies of the issues you
missed (while they last.)
Another way that departments can contribute to the
support of CEE-and also benefit their graduate programs
-is to advertise in the Fall 1971 special graduate educa-
tion issue. This issue consists mainly of articles on gradu-
ate courses that are written by professors at various

universities and of advertisements placed by departments
of chemical engineering describing their graduate pro-
grams. Each department is provided with several free
copies to distribute to seniors who are interested in
graduate work and to some of their graduate students.
Last year 51 schools placed advertisements in
this issue as compared with 39 schools in 1969. However
so far this year we have received indications from only 31
schools that they will advertise in 1971. Since some schools
may not have received the letter we sent to department
chairmen in early March, we are extending the deadline for
receipt of advertising copy to June 1, 1971. With regard to
editorial content, we are pleased to announce that we have
received a good response to our request for papers on
graduate courses. However it may still be possible to add
one or two additional papers. If you would like to prepare
a paper for this issue, please contact us as soon as pos-
sible. Papers that cannot be published in the Fall will be
considered for publication in later issues. Our selection of
papers is based on the objective of achieving a balance
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-. Date

Title of course


0hiichdl Reacdet &UGo4at4 o


Princeton University
Princeton, N. J. 06520

T HIS IS THE first of a series of articles de-
scribing the development and operation of
several new experiments as part of an undergrad-
uate laboratory course for seniors in chemical
engineering. The course was initially offered at
Princeton as an elective for seniors in the spring
term following a fall lecture course in chemical
kinetics and reactor design. Recently, the number
of laboratory sessions was reduced and laboratory
and lecture courses were combined into a single
course required of all students majoring in chemi-
cal engineering.
Professor Richard H. Wilhelm provided in-
spiration and guidance for the successful develop-
ment of the reactor laboratory. Other members
of the faculty-Donald E. Jost, Ronald P.
Andres, and James B. Anderson-were directly
responsible for development of the experiments
and instruction of students. Most of the experi-
ments were designed, built and tested by grad-
uate students of the department serving as teach-
ing assistants.
The laboratory was designed to emphasize
reactor properties rather than reaction proper-
ties. Four main ideas are illustrated: 1) Modes
of operation (batch, CSTR, tubular flow), 2)
Regimes of operation (predominance of chemical
rates, mass transfer rates and heat transfer
rates), 3) Classes of reactions (homogeneous,
heterogeneous, biological), 4) Measurements of
pertinent physical rate processes. In several of
the experiments the coupling of chemical, thermal
and diffusional efforts are illustrated. Many of
the important experimental techniques for re-
actor studies are utilized.
Listed in Table I are a total of eleven experi-
ments developed and utilized in the course. A
number of the experiments have been used in
laboratory courses by other departments and
have been described in some detail previously
(1, 2). In this series we will consider only those

*Present address: Department of Engineering and
Applied Science, Yale University, New Haven, Conn.

experiments which are sufficiently new to war-
rant a full description. The first of these demon-
strates thermal effects for an exothermic reaction
occurring at the surface of a catalytic wires.

W WHILE THE PHENOMENA of stability of
reactor systems are familiar in everyday life
(ignition and extinction of matches, etc.), the
bridge between theory and practice needs consid-
erable reinforcement before students develop an
intuitive feel for stability phenomena in reactor
systems. This experiment provides a demonstra-
tion of reactor operation in two stable stationary
states together with ignition and extinction in a
system whose thermal characteristics can be
measured. Measurements of the heat generation
and removal characteristics are used by students
to predict the overall behavior of the system.
These predictions are compared with actual be-
havior observed. In this way the theory of re-
actor stability is directly related to experimental
The reaction system used stems from self-
lighting cigarette lighters in which catalytic
wires above an alcohol-saturated pad glow red
hot when exposed to the air-alcohol vapors and
ignite the alcohol on the pad. In the experiment
a helium-oxygen mixture saturated at 0C with
methyl alcohol is passed over a short length of
platinum wire in a heated chamber. Since the
alcohol concentration is below that for a flamm-
able mixture, reaction occurs only at the wire.
Wire temperature is determined from electrical
resistance measurements. The heat removal and
heat generation characteristics at the wire are
determined from measurements of electrical heat
input required to maintain various wire tempera-
tures at several chamber temperatures both with
and without methanol present. To determine
ignition and extinction temperatures for a neg-
ligible electrical heat input, the chamber tempera-
ture is varied slowly while the wire resistance is
monitored. Since the wire does not glow red hot
after ignition, all observations must be made by
way of the wire resistance.


Table I. Reactor Laboratory Experiments
1. Batch Reactors: Hydrolysis of Acetic Anhydride.
2. CSTR Systems: Hydrolysis of Acetic Anhydride.
3. Tubular Flow Reactors: Hydrolysis of Acetic
4. Gas Chromatography: Analysis of Alcohol-Ketone
5. Heterogeneous Catalysis: Isopropanol Dehydro-
genation and Dehydration.
6. Diffusion and Reaction in Catalyst Pellets: TCC
Catalyst Regeneration.
7. Stability of Reactor Systems: Methanol Oxidation
on a Platinum Wire.
8. Biological Reactions: Kinetics of Yeast Growth.
9. Fluidized Beds: Study of Major Characteristics.
10. Diffusion in Porous Media: Knudsen Flow in
Catalyst Pellets.
11. Diffusion in Packed Beds: Dye Tracer Studies.


the t h e r m a characteristics of reactors
have been admirably summarized by Denbigh4,
Aris5, Kramers and Westerterp6 and Frank-
Kamenetskii7. The methanol oxidation system
used corresponds in many respects to a CSTR
system. Except for end effects the wire tempera-
ture is essentially uniform. Reaction occurs at a
single temperature and the system need not be
considered a distributed-parameter system. A
plot of the rate of heat generation by reaction
against wire temperature has a sigmoid shape.
At lower temperatures the reaction is rate-con-
trolled while at higher temperatures the reaction
is diffusion/transport-controlled. Depletion of
reactants in the chamber is believed to be negli-
gible under the conditions used. The process of
transport of reactants and products is a combina-
tion of molecular diffusion with thermal and
forced convection. A plot of heat removal rate
against wire temperature shows the expected in-
crease with difference between wire temperature
and chamber temperature. The heat removal
corresponds to that in a CSTR with a heat trans-
fer surface. Heat removal from the wire occurs
by radiation in addition to conduction and convec-
tion. For the methanol oxidation system the
phenomena of multiple steady-states, ignition
and extinction by monetary heating or momen-
tary interruption of reaction, and spontaneous
ignition and extinction can be explained in terms
of the heat generation and heat removal curves.
The analysis for this system has a direct parallel
in the CSTR. Analysis of the transient behavior
of this system is undoubtedly considerably more
complicated than that of the CSTR and a direct

The laboratory was designed to emphasize reactor
properties rather than reaction

parallel may not exist. Transient behavior is not
examined with the present apparatus.

A schematic diagram of the system and a photograph
of the reactor are shown in Figures 1 and 2. The helium-
oxygen mixture is supplied from a cylinder, passed
through a rotameter and fed to a sparger immersed in
methanol at 0C. The saturated (or partially saturated)
gas passes through a coil to the air-jacketed reaction
chamber which contains the platinum wire. A by-pass
of the sparger is provided. Reactor exit gases are vented
within a fume hood. Hot air for the chamber jacket
is supplied by a hair-dryer type of heat gun. Resistance
of the wire is measured with a commercial Kelvin double
bridge circuit. Electrical current for resistance measure-
ments and for hating the wire is supplied by an auto-
mobile storage battery and a solid-state control circuit.

Figure 1. Schematic diagram of apparatus for determination of
thermal characteristics of methanol oxidation on a platinum wire.
The 90% helium-10% oxygen mixture is purchased
premixed in a conventional cylinder. The gas passes
through a pressure regulator, shut-off valve, rubber tub-
ing, control valve, and rotameter to the carburetor. Tygon
tubing ('/4-inch I.D.) is used downstream of the rota-
meter. The carburetor is a 2-inch I.D., 8-inch long
glass cylinder containing methanol in which a fritted-
glass sparger is placed. The carburetor is immersed in
ice water contained in a 4-inch I.D. wide-mouth
vacuum flask. The carbureted gas passes to the reactor.
A carburetor by-pass tube is provided with a pinch clamp.
The reactor chamber is a%/-inch I.D. glass tube, 6
inches long, contained at the top of a second glass tube
(2-inch I.D., 18 inches long) through which hot air from
a heat gun is blown. The reactor feed gas passes through
a tubing coil within the jacket for preheating prior to
entering the reactor. The platinum wire is suspended
in a horizontal loop at the center of the reactor. Exhaust
gases from the reactor and the jacket are vented at the
top of the reactor assembly. The heat capacity of the
system is deliberately low so that rapid temperature


Figure 3. Circuit diagram for current controller.

equilibrium can be obtained. The heat gun is wired for
control of its heating current with a variable transformer.
The platinum wire (0.003 to 0.005 inch diameter,
about 1.5 inches long) is spot welded to two copper rods
(3/32-inch diameter, tinned) held by a Teflon plug in-
serted (loose fit) in the top of the reaction chamber.
Holes in the plug allow gas exit and insertion of a ther-
mometer. Since wires are easily melted by overheating,
spare assemblies are kept on hand. Spot welding is
accomplished with a commercial spot-welding machine
common to vacuum tube shops.
A Kelvin double bridge circuit is required for meas-
uring the wire resistance because of the low resistance
and the high currents which are used. Since three resist-
ance ratios must be equal for balancing the bridge, a
mechanical linkage of two ratios is essential for rapid
measurements. With a slightly modified commercial
bridge (General Electric, No. 9069199G) resistance meas-
urements are made in a few seconds. The platinum wire
and the copper rods (negligible resistance assumed)
holding the wire are incorporated in the bridge.
The current control circuit is shown in Figure 3.
An automobile storage battery provides sufficient current
for more than five hours of experimentation. The circuit
provides smooth control of current to the wire (and
bridge) with the turn of a single dial. No feedback con-
trol is provided. Two ammeters, necessary for determin-
ing the power input to the wire, are included in the
control box.
For reasons of safety, the reactor assembly and car-
buretor are located behind Plexiglas shields located
within an exhaust hood. Provided the methanol concen-
tration in the helium-oxygen mixtures does not exceed
that corresponding to saturation at 0C, the carbureted
gas is not flammable at temperatures below 200C. With
higher methanol concentrations or at higher tempera-
tures, the mixture may be flammable and/or explosive.
To minimize the severity of a possible explosion, the
volumes of carbureted gas contained in the reactor and
in the carburetor are minimized.


Prior to measurements, the storage battery is charged
and the methanol flash is cooled to 0C. The platinum
wire is flashed at a yellow heat in air to remove any
contaminants. During experiments occasional flashing at
a yellow heat helps to maintain a constant catalytic
activity, but also risks melting the wire.
Initial observations of spontaneous ignition and ex-
tinction are made in order to check the activity of the
wire and set a gas flow rate for which these phenomena
are observable with chamber temperatures in the range
25-2000C. Usually flow rates in the range of 10 to 20
percent of full scale on the rotameter are suitable.
With a fixed flow rate and reaction chamber tempera-
ture the resistance of the wire is measured for a range
of wire currents. Measurements without methanol in the
feed give the heat removal-wire temperature curve since
the heat removal is equal to the electrical heat input.
If it is assumed that the heat removal for a given wire
temperature is unaffected by the presence of the methanol,
then the heat of reaction can, be taken as the difference
in electrical heat inputs with and without methanol
Measurements of heat removal and heat input by
reaction for a range of wire temperatures are taken at
several chamber temperatures. It is usually found that
heat input by reaction is dependent almost solely on wire
temperature and affected only slightly by chamber tem-
perature. The thermal characteristics of the system
under normal operating conditions make it impossible
to determine the heat input by reaction in the vicinity
of the steeply rising portion of the heat input-temperature
curve. Interpolation is necessary in this region.
The experiment is concluded with measurements of
the chamber temperatures for spontaneous ignition and
extinction. These points are located approximately at
first, then more accurately by changing chamber tem-
peratures at a slower rate to allow thermal equilibration
of the chamber-jacket assembly.


Students are in general able to obtain satis-
factory results in a 3-hour period. Because the
apparatus is simple, only a few minutes are re-
quired for examining it and preparing for opera-


0-IA 0-5A

Figure 2. Air-jacketed
reaction chamber.

tion. Students then seem baffled at the various
heat inputs and outputs involved and may spend
half an hour discussing these and arguing among
themselves over procedures. Once measurements
of heat removal and heat release by reaction are
underway, data accumulation is rapid. The
groups that plot the data immediately are able
to gain a full understanding of the thermal char-
acteristics of the system and predict stability be-
havior on the spot. Other groups may adopt and
follow a procedure without fully understanding
it and fail to determine the significance of their
data until after they leave the laboratory. Ques-
tions directed to the students during the labora-
tory help prevent this situation.
The initial confusion, even for well-prepared
students, in relating theory and practice in this
experiment indicates the need for the exercise.
In the course of the experiment this confusion is
usually replaced by understanding and an intui-
tive feel for this system, and it is hoped, for the
stability of reactors in general.
Thermal characteristics determined at the
ignition temperature in one experiment are shown
in Figure 4. Similar curves were obtained at
other temperatures. The ignition and extinction
temperatures could be predicted within 20-30C
from the room temperature measurements.



I- B

0. 1

.4 .6 .8 1.0 1.2 1.4 1.6 1.8
Figure 4. Thermal characteristics of reactor at the ignition tempera-
ture (1880C). Curve A-electrical heat input for helium-oxygen flow
without methanol. Curve B-electrical heat input with methanol
present. Curve C-heat released by methanol oxidation differencee
of curves A and B).
The system was first built for operation with
air saturated with methanol at 0C. The reaction
chamber was maintained at room temperature
only. Under these conditions reaction at an ele-
vated wire temperature was not sustained with-
out a large electrical heat input. Although meas-

urements of heat removal and heat released by
reaction could be made and transitions between
stationary operating points were observed, self-
ignition and extinction did not occur. The use of
a heated reaction chamber, which necessitates
the use of a less flammable gas mixture, allows
observations of ignition and extinction with a
negligible electrical heat input.
Experience indicates that an easily operated,
continuously variable current control and an
easily operated Kelvin bridge are essential to
rapid measurements. In an early version of the
apparatus, current was controlled by switching
resistors in series with the platinum wire and the
bridge lacked mechanical linkage of resistors.
Several minutes were required for each measure-
ment in this version.
1. B. E. Lauer, Chemical Engineering Laboratory
Problems, University of Colorado, Boulder, 1965.
2. K. B. Bischoff, Chem. Eng. Ed. 2, 126 (1968).
3. M. A. A. Cardoso and D. Luss, Chem. Eng. Sci. 24,
1699 (1969).
4. K. G. Denbigh, Chemical Reactor Theory, Cam-
bridge University Press, Cambridge, 1965.
5. R. Aris, Introduction to the Analysis of Chemical
Reactors, Prentice-Hall, New York, 1965.
6. H. Kramers and K. R. Westerterp, Elements of
Reactor Design and Operation, Academic Press, New
York, 1963.
7. D. A. Frank-Kamenetskii, Diffusion and Heat Ex-
change in Chemical Kinetics, Princeton University Press,
Princeton, 1955.

J. B. ANDERSON is an associate professor of chemi-
cal engineering in the Department of Engineering and
Applied Science at Yale University. He received his BS
from Pennsylvania State University, MS from the Uni-
versity of Illinois and PhD from Princeton University.
Professor Anderson taught at Princeton for four years
before joining Yale in 1968. His research interests are in
the fields of chemical kinetics and chemical reaction


eJ n laboratory

A Demonstration Experiment In

Cornell University
Ithaca, N.Y. 14850

for all solutions and melts of high polymers at
high shear rates, it is not an easy phenomenon to demon-
strate to a large number of people at once. Other aspects
of polymer solution behavior can be illustrated by using
extreme examples. Melt elasticity is shown by "Silly
Putty" which is readily available, and, in fact, already
familiar to most students. Flow birefringence and creep
recovery also can be shown,1. The elasticity of dilute
solutions of poly(ethylene oxide) giving rise to an
"uphill" flow of a liquid has been packaged as a demon-
stration experiment (Edmund Scientific Co.). Drag re-
duction in turbulent flow also is amenable to demonstra-
tion. However the non-linear dependence of stress on
rate-of-shear (or a viscosity which decreases on increas-
ing stress or rate of shear) usually involves using a
rotational apparatus with transducers connected to gauges
or recorders so that the results can be seen by a large
group at once.
There is one inexpensive type of capillary flow in-
strument which presents a range of stresses in a single
experiment. The variable-head viscometer2-4 consists
essentially of a cylindrical reservoir connected to a
capillary tube. When the liquid flows, the reservoir
empties in such a way that the logarithm of the height
in the reservoir (above the discharge enn of the tube)
decays linearly with time for a Newtonian liquid. Al-
though this can be used as the basis for a lecture
demonstration, there are inherent advantages to using a
triangular reservoir connected to a tube as in Fig. 1.

T O RUN THE experiment one fills the reservoir
first with a Newtonian fluid selected to give a flow
time of several minutes. Once the clamp is opened, mem-
bers of the class can call out a signal at equal intervals
of time, say 20 seconds. One of the students can mark
the liquid level on the front of the reservoir with a
crayon on each signal. If the reservoir is about 100 cm
high, the experiment is clearly visible to a class of over
100. Next, while the reservoir is being refilled with a
second (non-Newtonian) fluid, the points from the first
run can be plotted on a paper graph next to the reservoir
(as in Fig. 1). It is found that the points lie on a
straight line.
The same routine is followed for the second fluid. It
should be found that this time the reservoir does not

Ferdinand Rodriguez is a graduate of Case Institute
(BS '50; MS '54) and Cornell (Ph.D. '58). He has taught
at Cornell since 1958 in the area of polymeric materials
and rheology. He has published extensively in this area
and a text, Principles of Polymer Systems has recently
been published. A native of Cleveland, Professor
Rodriguez is a lay preacher in the Lutheran Church and
also a guitarist.

empty linearly with time. With proper selection, a non-
Newtonian fluid can be made to cross over the line for
the Newtonian fluid.

FOR A FLUID flowing through a capillary tube it
can be shown3 that the shear stress and rate of
shear (both referred to the wall) are:
Shear stress,
Tw 4L (1)
Rate of shear,

= 3 If ) l) (2)
4n It TOD31
where p is the fluid density, gm/cm3; h is height of fluid
in reservoir above the efflux point of the tube, cm; g, is
981 dynes/gm; D is tube diameter, cm; L is tube length,
cm; Q is rate of flow through tube, cm3/sec; and n is
Innr,/dlnyw (n = 1 for a Newtonian fluid).
Also, the viscosity (poise) is defined as
n = tw/Tw (3)
In the present apparatus, Q can be related to the change
of h with time by
Q = -A dh/dt (4)
where A is the cross-sectional area of the reservoir in
cm2 at a height of h. The reservoir is positioned so that
the apex of the triangle is at the same height as the
effluent point of the horizontal tube. This,

A =( ) h (5)
where B, W, and H are dimensions (in cm) of the reser-
voir in Fig. 1. Therefore, we have
T: = iYw (6)
w Y.


phgl n( 1+ 3n 2 BW) dh (7)
4L \ 4n (!L d(
For a Newtonian liquid all the terms are constant except
h, which cancels out, and n=l, which is the advantage
of the triangular reservoir. Now we have:
dh Trg \h l 4 BWJ (8)
dt l28JL)[ liBWj
The last three terms on the right are separate functions
of the fluid, the tube, and the reservoir. Of course, when
dh/dt is constant, h decays linearly with time.

Figure 1. Variable-head viscometer with triangular reservoir.

The analysis of the non-linear plot for the non-
Newtonian fluid can be carried out several ways. The
easiest is to define an "apparent kinematic viscosity" as

(n/pa = it (9)

(II = fI U&L (10)
p dhl 128 L BwW
The apparent viscosity is inversely proportional to
the slope of the h, t plot, Most polymer solutions are
"pseudoplastic", that is, the viscosity decreases with
increasing shear stress (which is readily calculated from
equation 1).

THE SUCCESS OF a lecture demonstration is always
affected directly by the choice of materials and con-
ditions. A reasonable model made by joining a glass tube

to an acrylic reservoir by rubber tubing has the dimen-
sions: B = 20 cm; W = 1 cm; H = 100 cm; L = 21.5 cm;
D = 0.40 cm.
From equation 8 we learn that

-(dh/dt) 81 (0.40 )0.143 (p/n) (11)
8 L 21.5 20'i,
If a reasonable flow time for h going from 90 down
to 20 cm is two minutes, then

(n/p) = 0.143 (120/70) = 0.245 stoke
or about 25 times the viscosity of water. The shear stress
is given in dyne/cm2 by equation 1 when p is in gm/cm3
and h is in cm:

S481)= i )p 56ph (12)

Figure 2 shows a non-Newtonian polyacrylamide
solution (0.94 wt.%) crossing over the straight line for
a poly(vinyl alcohol) (4.0 wt.%) solution. The viscosity
of the Newtonian solution is 0.56 stoke since -dh/dt =
0.254 cm/sec. When the slope of the other curve is plotted
against h (Figure 3) a straight line results. This means
that the fluid can be represented by the "power-law"
model in this range of stresses.
w = K (13)
From equations 10 and 11 we can derive
(/P)a = 0.143 (-dh/dt) (14)
This, with equations 12 and 13 (and with p = 1.0 gm/
cm3) can be rearranged to give
(-dh/dt) = 0.Ol0 (4.56/K) 1/n (4n/3n+)h(-n)/n (15)
From the slope in Figure 3, n = 0.59, and from the
intercept, K = 4.73 dyne, sec. 0.*5/cm2. This is in good
agreement with the behavior of this same polymer solu-
tion in rotational viscometers5.
Most water-soluble polymers that have an intrinsic
viscosity less than two will give Newtonian solutions
under the conditions of this experiment. In addition to
poly(vinyl alcohol), some other materials are hydroxy-
ethyl cellulose, dextran, poly(vinyl pyrrolidone), poly-
acrylamide, glycerol, and the lower glycols. On the other

Poly(vinyl alcohol), 4.0 Wt.%

0.94 Wt. %

100 200
Time, sec.


Figure 2. Head decays linearly with time for the Newtonian solu-
tion but not for the pseudoplastic solution. Both aqueous solutions
were run at 250C with L = 21.5 cm, D = 0.40 cm, and (BW/H)
= 0.20.



MARTIN J. BUERGER, Massachusetts Institute
of Technology and the University of Connecticut.
McGraw-Hill Series in Materials Science and
Engineering. 224 pages, $12.50
The author, a distinguished crystallographer and
recipient of the 1971 Fankuchen Memorial
Award, has written a book that is authoritative
and rigorous yet still affords an easy introduc-
tion to crystal science for the undergraduate. It
develops the theory of order in crystals, homo-
geneous patterns, symmetry and symmetry of
elements, lattices, cells, indices, point groups,
crystal systems and space groups. The discussion
is illustrated by numerous line drawings, and the
results obtained are listed in many convenient

MARTIN J. BUERGER. McGraw-Hill Series in
Materials Science and Engineering. 384 pages,
This book (1) introduces the characteristic fea-
tures of crystals, (2) outlines the theory and
results concerned with their basic geometrical
features, and (3) analyzes the modern methods
of experimentally determining them. No knowl-
edge of advanced mathematics is assumed, al-
though some is introduced in easy stages as

HEAT TRANSFER, Second Edition
BENJAMIN GEBHART, Cornell University.
608 pages, $18.50
Beginning with a relatively rigorous examination
of fundamentals, this work progresses to an up-
to-date account of the state-of-the-art in several
very important new areas in heat transfer, e.g.,
radiation transport, and natural convection. More
detailed presentations of the following are also
offered in this new edition: conduction mechan-
isms, the nature of radiation processes, and,
particularly, the nature of flows and transport
in fluids.

C. JUDSON KING, University of California,
Berkeley. McGraw-Hill Series in Chemical Engi-
neering. 832 pages, $19.50
Departing from the classical approach to the sub-
ject, this text treats industrial separations as a

general problem, and stresses the many common
aspects of the functioning and analysis of differ-
ent separation processes, e.g., distillation, ab-
sorption, extraction, etc. The author's purpose is
to promote a basic understanding of the concepts
underlying the selection, behavior, and computa-
tion of separation processes, as well as to convey
the "flavor" of real process engineering.

GLEN E. MYERS, University of Wisconsin. 500
pages (tent.), $18.50 (tent.). Available April,
Instead of examining all existing classical solu-
tions, this book concentrates on a number of
analytical methods for solving conduction heat
transfer problems. The first half of the book
discusses exact techniques; the second half em-
phasizes computer methods. Material is devoted
to the finite-difference method, as well as the
finite-element method, a subject which has never
previously been presented in a heat transfer text.

RAYMOND B. SEYMOUR, University of Hous-
ton. 448 pages, $16.50
Completeness is the keynote; probably the only
modern textbook that describes all phases of
polymer chemistry. A unified approach is used
to describe the chemistry of all polymers, namely,
natural and synthetic polymers, fibers, elasto-
mers, plastics and polymer coatings.


OPTIMIZATION: Theory and Practice
GORDON S. G. BEVERIDGE, Heriot-Watt Uni-
versity, Edinburgh and ROBERT S. SCHECH-
TER, University of Texas. McGraw-Hill Series
in Chemical Engineering. 704 pages, $18.50
This book's purpose is threefold: (1) to offer a
unified theory of optimization, (2) to present
nonlinear programming algorithms to the con-
trol engineer, and (3) to introduce the nonlinear
expert to optimal control. Much of the material
contained in the book, specifically Chapters 2
through 4, 6 and 8, is original and has never
previously appeared in book form.


ROBERT D. KERSTEN, Florida Technological
University. 224 pages, $13.00
The objective of this book is to unite facets re-
quisite to solving engineering differential sys-
tems. The author explores this concept by stating
the system's essential and equally important
parts: (1) properly understood phenomena,
(2) correct mathematical models of the phenom-
ena, (3) a tentative solution, and (4) a proper
application of boundary or initial conditions or
both. A complete solution is achieved after these
four parts have been integrated through a rati-
onal engineering mathematical analysis.

PRAWEL, JR., both of the State University of
New York, Buffalo. 512 pages, $15.50
This volume presents an introduction to the field
of modern computational methods in terms in-
telligible to the second- or third-year student,
develops from these various methods the first
principles that are basic and/or in general usage
and indicates the interrelationships among them,
and views the material specifically but yet gener-
ally enough to give the student the background
he will need in numerical methods to cope with
future engineering courses.

ENGINEERING, Second Edition
WARREN L. McCABE, North Carolina State
University and JULIAN C. SMITH, Cornell Uni-
versity. McGraw-Hill Series in Chemical Engi-
neering. 832 pages, $16.50
While maintaining a balance between theory and
practice, this text covers the standard unit opera-
tions in chemical engineering. Specific topics that
have been improved and modernized in this
edition include: coordination of momentum, heat
and mass transfer, turbulent flow and its applica-
tion to fluid mechanics, compressible fluid flow,
nucleation, crystal growth, etc.

EDWARD L. McCAFFERY, Lowell Technologi-
cal Institute. 416 pages, $12.50
One of the first books to provide a complete pro-
gram for a polymer laboratory, this book in-
corporates topics in the organic, physical and
analytical chemistry of macromolecules. The
author offers both an elaborate theoretical intro-
duction to enable the student to comprehend the
principles involved in the experiment, and a de-
tailed presentation of the experimental instruc-
tions to facilitate the mechanical operations.

HAUS, both of the University of Colorado. Mc-
Graw-Hill Series in Chemical Engineering. 704
pages, $17.50
The first part of this text presents an overall
analysis of the major factors involved in process
design, emphasizing economics in the process in-
dustries and design work. Cost estimation, cost
accounting, optimum economic design methods,
and other relevant subjects are covered both
quantitatively and qualitatively. The remainder
of the book discusses methods and important ele-
ments in the design of plants and equipment

FERDINAND RODRIGUEZ, Cornell University.
432 pages, $18.50
Providing information on all important phases
of polymers, this text enables the student to des-
cribe polymers quantitatively and manipulate
quantitative data to predict and correlate the
behavior of real polymer systems. This is accomp-
lished by relating, where feasible, the qualitative
behavior of polymer systems to everyday ex-
amples; and including numerous problems that
give the student experience in the quantitative
behavior of these systems.

Second Edition
ROBERT E. TREYBAL, New York University.
McGraw-Hill Series in Chemical Engineering.
736 pages, $16.50
The basic approach, which treats the major sub-
jects in categories of gas-liquid, liquid-liquid, and
fluid-solid contact, has been retained in this
edition as has the application of modern theories
and data to the practical design of equipment.
This revision features new material on multi-
component gas absorption and distillation.

H. C. VAN NESS, Rensselaer Polytechnic Insti-
tute. 128 pages, $4.95, $2.95 (soft)
In this short book, the author has presented the
basic concepts of thermodynamics in a way that
demonstrates their usefulness and plausibility.
The book is not intended to supplant a textbook
in thermodynamics, but rather to act as a sup-
plement that will help the reader with the diffi-
cult ideas that he must grasp as a beginning
student of thermodynamics. The language is in-
formal; the treatment clear.
F McGraw-Hill Book Company
330 West 42nd Street
New York, N.Y. 10036






Poly (vinyl
alcohol) >


dh/dt 0.0 1O95hoA 0

I I I t I Ilt

10 20h,cm 50


Figure 3. The logarithm of the slope for the non-Newtonian solu-
tion taken from Figure 2 increases linearly with log h corresponding
to a power-law model.

hand, a non-linearity for the non-Newtonian material
demands a very high molecular weight. Poly(ethylene
oxide) is available which performs very well (Polyox
FRA, Union Carbide Corp.). The polyacrylamide used
here was made by placing a beaker containing a mixture
of 50 gm acrylamide, 50 gm water, and 0.001 gm ribo-
flavine-5'-phosphate sodium on the light table of an over-
head projector for 10 minutes6. The resulting polymer
gel dissolved in sufficient water to make a 1 wt.% solu-
tion while being gently rocked for one week.

Figure 4. Drag-reduction by a small addition of polymer to water
is shown in turbulent flow Nre = 2100 at about h = 20). For
this experiment at 250C, L = 91.5 cm, D = 0.30 cm, and (BW/H)
= 0.20.

ups in tandem so that both solutions can be run
at once. The effect of having the Newtonian fluid flow
more slowly than the other at first, but then catching up
and passing up the non-Newtonian fluid in tortoise-like
fashion illustrates the difference in behavior even without
recording the time dependence of head.
The same apparatus can be used for an experiment
in turbulent flow. The common parameters are the fric-
tion factor, f, and Reynolds number, N,,.
f = (hDgc)/(2L2) (16)

N = Dup/pr (17)
The average velocity, ii, is given by
u = (BW/H) (4/7T) (h/D) (-dh/dt) (18)
Since f changes slowly with N,,, the qualitative predic-
tion of equations 16 and 18 is
-dh/dt a (1/h)1/2 (19)
The increase in slope with decreasing h is borne out by
experiment (Figure 4) down to the point where laminar
flow sets in (N,,= 2100).
A small amount (56 parts per million) of the poly
(acrylamide) will make the reservoir empty even faster
due to the well-known phenomenon of drag-reduction7-..
From raw data of head versus time, the student should
be able to construct a friction factor, Reynolds number
plot. In turbulent flow experiments, end effects must be
taken into account to achieve agreement with literature
values of friction factors.
In all experiments with this apparatus, temperature
control is difficult so that there is an inherent limit to
the accuracy obtainable. Two other complications are the
drainage error and surface tension. The first is aggra-
vated by fast flows with viscous fluids. The second can
be compensated for by first dipping the flow tube in the
liquid and then aligning the apex of the triangular reser-
voir with the meniscus of the liquid in the tube rather
than with the effluent point.

1. F. Rodriguez, Principles of Polymer Systems, Mc-
Graw-Hill, New York, p. 512 (1970); F. Rodriguez,
J. Chem. Ed. 46, 456 (1969).
2. W. Ostwald and R. Auerbach, Kolloid-Z., 41, 56 (1927)
3. S. H. Maron, I. M. Krieger, and A. W. Sisko, J. Appl.
Phys., 25, 971 (1954).
4. F. Rodriguez and A. J. Berger, Proceedings of the
Fourth International Congress on Rheology, Part 3,
H. E. Lee, Ed., Interscience, New York, p. 41 (1965).
5. F. Rodriguez and L. A. Goettler, Trans. Soc. Rheology,
8, 3 (1964).
6. G. K. Oster, G. Oster, and G. Prati, J. Am. Chem.
Soc., 79, 595 (1957).
7. G. K. Patterson, J. L. Zakin, and J. M. Rodriguez,
Ind. and Eng. Chem., 61, (1) 22 (1969).
8. J. L. Lumley in Annual Review of Fluid Mechanics,
Vol. 1, Ed. by W. R. Sears and M. Van Dyke, Annual
Reviews, p. 367 (1969).


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mI iN curriculum


University of Kentucky,
Lexington, Kentucky 40506

background for graduate work in water pollu-
tion control engineering is open to question; both
chemical engineering and civil engineering have
certain advantages. However, for graduate work
in air pollution control engineering, there is vir-
tually no question concerning the most appropri-
ate background. The chemical engineer, with his
knowledge of chemistry, engineering thermody-
namics, diffusion and mass transfer, process con-
trol, and process design is best prepared, in com-
parison with BS degree holders in the other engi-
neering and physical science disciplines.
At the University of Kentucky, a specialized
MS program was initiated two years ago to give
advanced training in air pollution and its control.
The program is designed to prepare chemical en-
gineers and some mechanical engineers) for em-
ployment by municipal, state, or federal (Public
Health Service) control agencies, by industries
selling in the air pollution control market, and
by industries with air pollution problems. At
present there are eight full-time graduate stu-
dents in the program (not including those in the
"regular" chemical engineering MS and PhD pro-
grams), and eight MS degrees in chemical engi-
neering with specialization in air pollution have
been awarded in the past twelve months.
T HE MS PROGRAM consists of three parts.
First, an acceptable thesis is required on a
topic associated with atmospheric pollution and
its control. Thesis topics range from research on
chemical and physical processes for SOx and
NOx control to research on the transport of pol-
lutant gases through the human respiratory sys-
tem. Second, four graduate courses (3 semester
hours each) in chemical engineering and mathe-
matics fundamentals are required:
(1) Equilibrium Thermodynamics, (2) Transport
Phenomena or Advanced Transport, (3) Engineering
Statistics or Applied Calculus II, and (4) Chemical
Reactor Design or Advanced Reactor Design, or
Process Control or Advanced Process Control.

A/4 Pa1d4 ibo

The third requirement is a series of four
courses, constituting the air pollution core. In
the core, an effort is made to convey the breadth
of the field; however, by utilizing a total of 12
semester hours (one full semester of graduate
work) sufficient depth can be achieved in several
important facets of the field. A fifth course,
taught in mechanical engineering on fuels, com-
bustion, emission evaluation, and stack and auto-
motive sampling is often taken by chemical en-
gineering air pollution students. An air pollution
seminar, using both outside and in-house speak-
ers, attempts to alleviate some deficiencies in the
area of biological and health aspects.
the basis for the air pollution core. The overall
approach of the core is first the proper evaluation
of the effects of the numerous air pollutants, lead-
ing to the establishment of air quality standards;
and then a consideration of the reactions and
transport of pollutants in the atmosphere, which
provides the connection between air quality stan-
dards and emission standards. Based on emission
standards, the specific problem of air pollution
control can be put into perspective, first consider-
ing the design of control measures and gas clean-
ing devices and then the evaluation of the effec-
tiveness of the control.
oan materials
& effects of air pollutants-. vegetation
I an animals
(criteria) on humans
[ pollutant ; a. l ualitf standards -kinetics and equilibria of
c..etiome tt 9 l light and dark reactions
I) atmospheric reactions
2) micrometeorolagy
3) turbulent diffusion
{ thermodynamics and emissn standard
horizontal and vertical
rdton @ air pollution control
a) process and system control
b) gas cleaning
fparlticulete pollutants control effctlVeness
soluble pollutants air sampling and
b) legal and
ambient and stack
Figure 1. Design for air pollution core courses.

Each of the four numerals in Figure 1 indi-
cates one of the core courses. A specific text is
not used in any of the courses, principally because
there is no appropriate textbook in the field. In
the four courses extensive use is made of A. C.
Stern's Air Pollution (Academic Press, 1968)
which in its three volumes and 2200 pages covers


When compared with other BS degree holders
the chemical engineer is best prepared for
graduate work in air pollution control

the breadth of the field. For the most part, cur-
rent research papers (Stern has provided an ex-
cellent literature review through 1967), govern-
ment publications including the Air Quality Cri-
teria series and the Control Techniques series,
and handout material on such topics as reaction
mechanisms in photochemical smog and design
approaches for gas cleaning devices are adequate
substitutes for a text. A paper-bound text by
W. P. Lowry and R. W. Boubel, Meteorological
Concepts in Air Sanitation (published by the
authors at Oregon State University, 1968), is
used for about one third of the course on the
reactions and transport of pollutants. Outlines of
the four core courses are given in Table 1.

I. Air Pollutant Effects
A. Effects of air pollutants on the atmosphere
Alterations to radiation
Effects on weather
Changes in the constituents of the natural
B. Effects on vegetation and foraging animals
Types of injury to plants, causative agents,
conditions of exposure
Ambient and laboratory bioassay
Susceptibility of livestock
C. Effects on man
History of acute episodes
D. Effects on materials
General deterioration and specific materials
Economic considerations
E. Airborne, waterborne, and solid wastes
Interrelationships of potential and of control
Ultimate disposal
II. Reactions and Transport of Pollutants
A. Atmospheric chemistry
Basic concepts; kinetics, photochemical re-
actions, heterogeneous reactions
Inorganic atmospheric reactions; scavenging
Organic reactions; photochemical smog
B. Atmospheric thermodynamics and stability;
pseudoadiabatic chart
Thermodynamics and psychrometry
Statics, lapse rates, stability
Applications of the pseudoadiabatic chart
C. Atmospheric motion
Scales of motion
Wind speed variation
Small scale vertical motion

Robert B. Grieves is Professor and Chairman of the
Department of Chemical Engineering at the University
of Kentucky and is director of a graduate training pro-
gram in air pollution control. He received MS and PhD
degrees in chemical engineering at Northwestern and has
taught at Northwestern and at the Illinois Institute of
Technology. His interests include membrane transport,
foam separation, and air and water pollution control

Air pollution climatology: air patterns, stag-
nation, and inversions
D. Diffusion in the atmosphere
Model of area-source diffusion
Single stack emission,; plume characteristics
Models for diffusion
E. Atmospheric radiation; energy budget
III. Air Pollution Control
A. Removal of soluble pollutants from air streams
Application of principles of mass transfer
Engineering considerations of absorber design
adsorption applications; the adsorption pro-
cess; design
B. Removal of particulate pollutants from air
Efficiency and selection of collectors
Cyclone separators
Gravity and impingement collectors
Electrostatic precipitators
C. Process and system control
Elimination of emissions
Minimization of emissions
Concentration of air pollutants at the source
Optimization of combustion
D. Use of current literature for control problems
IV. Effectiveness of Control
A. Broad considerations in sampling
Site criteria; sampling network; statistics
B. Review of analytical techniques
Radiation instrumentation; electrical; mass
spectrometry; chromatography
C. Passive effect devices
D. Sampling proper
Aerosol sampling; gas sampling absorption,
absorption, and condensation.


E. Analysis of particulates
Physical; inorganic chemical; organic chemical
F. Odor in ambient air
G. Analysis for gaseous pollutants
Inorganic gases; organic gases
H. Legal and administrative aspects
Students specializing in air pollution are
studying a problem and the approaches to its
solution. Consequently, two potential dangers
must be carefully watched and avoided: first, that
the core program can become too broad and too

qualitative. To overcome this danger, funda-
mentals are stressed whenever possible, for ex-
ample in considering atmospheric photochemis-
try or atmospheric diffusion, and engineering
design is introduced whenever possible, for ex-
ample in gas cleaning. The second concern is that
the problem and the approaches to its solution
change very rapidly. To overcome this danger,
the only answer is the use of the latest research
and development publications in the field.



University of Rochester
Rochester, N. Y. 14627
Process dynamics has traditionally been
closely associated with the field of process control.
Indeed it was a natural marriage. Control sys-
tems by their very nature modify the unsteady
state response of a process. However, process
dynamics need not be so restricted in application.
Clearly such diverse problems as dynamic meas-
urement of theological properties, batch process-
ing, molecular excitation and relaxation, periodic
operation of processes and the onset of hydro-
dynamic instabilities all have a common founda-
tion in process dynamics. Problems in stability,
for example, arise not only in analysis of control
systems, but also in thermodynamics, boiling heat
transfer, reactor analysis and hydrodynamics,
among others.
There is a need then for a common funda-
mental discipline concerned with unsteady state
problem is engineering. Presentation of dynamic
ideas may come in a rather natural context in
control system analysis. It is the writer's ex-
perience that more difficulties arise when pres-
ented in other surroundings. Chemical engineers
have been traditionally steeped in steady state
concepts. From the period when analytical de-
scription of processes became feasible, continu-
ous steady state operation was the ideal. Only
recently has this accepted norm been challenged.
Periodic operation of processes can prove to be
optimum in some economic sense. So ingrained
is the steady state concept though, it is often

difficult to get across the idea that a process cycle
is not necessarily a repeating sequence of differ-
ent steady states. This could be remedied by
proper exposure to the fundamental concepts of
process dynamics.
T HE NEED FOR A fundamental understand-
ing of process dynamics, divorced from specific
fields of application, increases each year. Engi-
neers are being called on to contribute their tech-
ology to important social problems. Blind appli-
cation of traditional chemical engineering tech-
niques to problems in biomedical and environ-
mental engineering, for example, might prove
disastrous. It is perhaps clear that processes
occurring in the human body vary continually
with time. The steady state concept may be vir-
tually nonexistent there. Application of steady
state analysis to environmental problems may be
more insidious. A large lake, for example, may
respond to changes with a time constant on the
order of months rather than minutes. Changes
with time may be so slow that the natural tempta-
tion would be to assume that a quasi-steady state
prevails. Serious errors may result in trying to
use steady state models to describe observed data.
The basic ideas of process dynamics must be
incorporated into any chemical engineer's educa-
tion. It is the writer's opinion that process dy-
namics should be taught in a core of funda-
mentals. Process control is an application of
these fundamentals, but only one of a variety of
applications. To a certain degree process dy-
namics is to process control as transport phe-
nomena is to diffusional operations.


John C. Friedly is a native of West Virginia. He was
educated at Carnegie Institute of Technology, Pittsburgh
and the University of California at Berkeley, receiving a
PhD in 1965. He has taught at the University of Rochester
and the Johns Hopkins University. Industrial exper-
ience includes three years with General Electric Com-
pany, as well as consulting activities. He is the author
of Dynamic Behavior of Processes which will be pub-
lished by Prentice-Hall in late 1971. Research interests
include process dynamics, automatic control, heat trans-
fer, combustion and systems analysis.

These ideas are continually being incorpor-
ated into a one semester graduate level course
entitled Process Dynamics taught at the Univer-
sity of Rochester. The course has evolved over
several years, first being taught by the writer on
the informal basis in an industrial environment
and then at The Johns Hopkins University. The
intent is to present a unified treatment of the
unsteady state behavior of processes. Emphasis
is on the physical interpretation of the time
responses as well as the mathematical methods
of analysis. Applications, in the form of ex-
amples, are taken from a spectrum of areas.
Students taking the course have a variety of
backgrounds. No previous exposure to process
dynamics or process control is required and in-
deed some have had none. The course is nor-
mally offered in the Spring semester so all stu-
dents are expected to have a degree of mathema-
tical maturity. Background in linear algebra,
Laplace transforms, and techniques for solution
of partial differential equations is built on. In
addition to first year and more advanced chemical
engineers both mechanical and electrical engi-
needs have enrolled. Full and part time students
are included.
No attempt is made to cover applications to
process control with any breadth. There is per-
haps a bias toward these problems, but no syste-
matic treatment. Students interested in advanced

control concepts are encouraged to take a course
in advanced servomechanisms taught in the Elec-
trical Engineering Department or optimal control
theory taught in the Mathematics Department
at Rochester. The course in Process Dynamics
provides sufficient motivation and background
material for either. At present no course on con-
trol of chemical processes is offered, although one
is currently being planned.

T ABLE I PRESENTS an outline of the course
content. It is divided into three major parts,
the first being a rather brief introductory and
motivational section. The remainder of the course
is divided roughly into equal parts, treating
problems described by ordinary differential equa-

Table I. Process Dynamics-Course Content
I. Motives and Methods of Process Dynamics
A. Introduction
Illustrative examples; dynamic versus static
B. Dynamic Process Models
Lumped and distributed parameter systems
C. Methods of Analysis
Perturbation methods, linearization; linear
algebra; Laplace transforms
II. Lumped Parameter Systems
A. Input-Output Representation
Transfer functions; time responses, short and
long time expansions; frequency response;
linear stability; Nyquist criterion
B. State Space Representation
Matrix exponential; eigenvalues, eigenvectors
and response modes; modal control; optimal
system responses
C. Nonlinear Responses
State plane response; perturbation methods;
periodic processing; stability in the sense of
Lyapunov, Lyapunov functions and system re-
III. Distributed Parameter Systems
A. Linear Constant Coefficient Problems
Wave and diffusion responses; simple time and
frequency responses; Riemann representation,
the method of characteristics; Laplace trans-
form techniques, short and long time expan-
sions; axial dispersion, Taylor diffusion; sta-
bility considerations; optimal responses
B. Variable Coefficient and Nonlinear Problems
Local linearization, relation to Riccati equa-
tions; some exact solutions; nonlinear prob-
lems, flow forcing problem, shockwaves; per-
iodic processing, the parametric pump; appli-
cation of modified lumped parameter methods
of analysis.
C. Approximation techniques
Relation between lumped and distributed sys-
tems, discretization; method of moments;
modal approximation; successive approxima-
tions; asympotic approximations.


tions and those arising from partial differential
equation models. These are termed lumped and
distributed parameter systems in control jargon.
As an introduction to the subject of process
dynamics several diverse examples are discussed
qualitatively. It is important to carefully dis-
tinguish between the true unsteady state and the
quasi-steady and steady states. Only the first is
a purely dynamic state in which there is a vary-
ing rate of accumulation of mass, energy or mo-
mentum. Then typical process models are con-
sidered as a basis for the general types of systems
to be considered. Since all involve simply appli-
cations of conservation equations, models in-
variably are coupled systems of first order differ-
ential equations or first order (in time) partial
differential equations.
Although an attempt is made to review or
introduce mathematical tools in the context of
the applications being considered, some introduc-
tion is given to the principal methods of analysis
used throughout the course. The application of
perturbation methods to general nonlinear equa-
tions is discussed to provide experience in obtain-
ing linearized models to analyze. Care is taken to
justify linearization not because real processes
are linear but because only then can general
analysis and interpretation be performed. Con-
sequently most methods of analysis of nonlinear
problems extend or build on the linear.
Treatment of lumped parameter systems is
begun with a quick review of standard Laplace
transform treatment of linear ordinary differen-
tial equations. Emphasis is placed on the physi-
cal, time domain, responses of these systems.
Both long and short time expansions of trans-
forms and their time responses are discussed.
Transfer functions and their frequency response
are treated only as they represent physical sys-
tem models and their time response to sinusoidal
disturbances. Typical example problems consid-
ered in this treatment might include the inter-
pretation of complex viscosities obtained in
theological measurements or the choice of a forc-
ing signal tending to amplify a system response
the most.
More time is spent treating the same general
Nt" order system of linear lumped parameter
equations from the state space point of view.
General solutions are written in terms of the
fundamental solution of the adjoint system of
equations. The matrix exponential and the system
eigenvalues, eigenvectors and response modes are
interpreted physically. At each step full compari-

son is made between the same results obtained by
general Laplace transform solutions and the state
space solution. The problem of feedback control
is introduced to illustrate that it is possible to
tailor the dynamic response of systems to suit
ones need. As a further example of the advantage
of using the state space point of view the optimal
control problem is considered. Elementary solu-
tions to the variational problem are considered in
Stability of linear systems is also treated from
both the frequency response and state space points
of view. Careful explanation of the feedback
nature of the problem, either inherent or im-
posed, is included. From a general treatment of
the analysis of roots of a characteristic equation
the frequency domain methods are derived. In
order to convey a physical feeling of the origin of
the instability problem, example problems from a
wide variety of areas are discussed. Both an-
alysis of multiplicity of steady state solutions
and of oscillatory storage and release of system
"energy" are discussed physically and demon-
strated mathematically.
The growth of a linearly unstable response to
the point at which the linear model is no longer
valid naturally introduces the analysis of non-
linear systems. The extensive work done on
stirred tank reactor analysis can be used to illus-
trate the methods of classical nonlinear mechanics
and the use of Lyapunov functions. Methods of
analysis are developed as needed and compared
with the limiting cases of linearized models. State
plane dynamics and the geometric interpretation
of stability in the sense of Lyapunov are rather
easily presented after the linear canonical state
space concept is grasped.
Although much of the material on lumped
parameter systems is available in a variety of
suggested textbook references, a conscious effort
is made to use papers available in the literature
for examples. It is felt that in this way the stu-
dent is given a better feeling that these are indeed
relevant problems of current research interest.
In addition the point of view is made as broad as
possible. Table II includes representative sug-
gested references. Currently lecture notes are
also distributed to the student to provide a unify-
ing summary of the literature.

B ECAUSE OF THE importance of partial
differential equation models in chemical en-
gineering an attempt is made to spend nearly half
a semester on distributed systems. The nature

of distributed systems dictates that examples
from research papers be used much more than
general analysis. In contrast to lumped systems
there are no adequate textbooks available with a
systematic treatment of distributed parameter
systems. The use of current research papers is
not only advisable but necessary.

Table II. Representative References
I. Motives and Methods
A. Himmelblau and Bischoff, Process Analysis and
Simulation; Bird, etal, Transport Phenomena
B. Collins, Mathematical Methods for Physicists
and Engineers; Amundson, Mathematical Methods
in Chemical Engineering.
II. Lumped Parameter Eystems
A. Coughanowr and Koppel, Process Systems An-
alysis and Control; Campbell, Process Dynamics;
Aris, Introduction to the Analysis of Chemical Re-
B. DeRusso etal, State Variables for Engineers;
Rosenbrock, CEP 58, No. 9, 43, (1962); Lapidus
and Luus, Optimal Control of Engineering Process
C. G. Davis, Introduction to Nonlinear Differential
and Integral Equations; Minorsky, Nonlinear Oscil-
tions; Douglas and Rippin, Chem. Eng. Sci. 21, 305,
(1966); Horn and Lin, IIEC Proc. Des. and Dev.
66, 21, (1967) ; Lasalle and Lefschetz, Stability by
Liapunov's Direct Method; Berger and Perlmutter,
AIChE J. 10, 233 (1964); Gurel and Lapidus, I/EC
61, No. 3, 30, (1969)
III. Distributed Parameter Systems
A. Gould, Chemical Process Control; Koppel, Intro-
duction to Control Theory; Courant and Hilbert,
Methods of Mathematical Physics, vol. II, Chap. V.,
Taylor, Proc. Roy, Soc. A219, 186, (1953) ; Hsu and
Gilbert, AIChE J. 8, 593, (1962); Yang, J. Heat
Trans. 86, 133, (1964); Carslaw and Jaeger, Con-
duction of Heat in Solids
B. Bilous and Amundson, AICHE J. 2, 117 (1956);
Crider and Foss AIChE J. 14, 77 (1968); Stermole
and Larson, I/EC Fund. 2, 62 (1963); Koppel,
I/EC Fund. 1, 131 (1962); Hart and McClure,
J. Chem. Phy. 32, 1501, (1959); Orcutt and Lamb,
Proc. 1st IFAC Congress, vol. 4, p. 274; Wilhelm
etal, I/ES Fund. 7, 337, (1968)
C. Rosenbrock, and Storey, Numerical Computation
for Chemical Engineers; Paynter and Takahashi,
Trans. ASME 78, 749 (1956); Gould, Chemical
Process Control; Schone, Proc. 3rd IFAC Congress,
p. 10, b. 1.
Dynamic distributed parameter systems are
classified naturally as either hyperbolic or para-
bolic. Flow problems are most frequently sim-
plified to the extent that they belong in the
former class. After first looking at some simple
examples of transformed solutions to distributed
systems, the striking contrasts with lumped para-
meter results are drawn. Complex transcendental

transforms, infinite series time responses, and
delays are the rule rather than being nonexistent.
It is felt that a useful introduction to the types
of linear responses expected from hyperbolic sys-
tems can be gained using the time domain Rie-
mann representatives for the solution. The Rie-
to the adoint system of equations and serves the
same function as the matrix exponential in the
standard state space analysis. The analogous in-
terpretation of the Lagrange multipliers or
adjoint variables of the calculus of variations
problem ties these three subjects together neatly.
Fig. 1 illustrates the utility of the Riemann
representation as applied to the simple counter-
flow double pipe heat exchanger. The solution at
any position and time M(Q, r) is written as a
linear functional of the initial and boundary con-
ditions given between the points P and Q, con-
nected with M by the characteristic lines PM and
QP. The natural appearance of delays and their
relation to domains of dependence and influence
can be readily interpreted graphically and physi-
cally. From this, appearance of reflected waves
can be easily explained. Since the responses tc
all hyperbolic systems can be interpreted in terms
of system waves, this conceptual aid has a great
deal of utility.
Once the expected wave behavior is under-
stood thoroughly, it is a much more straightfor-
ward task to obtain and interpret solutions for
hyperbolic systems both in the time and frequency
domains. Recurring resonance phenomena in fre-
quency responses of these systems is easily ex-
plained. Methods of expanding and inverting
transforms of hyperbolic systems can be tailored
to the physical interpretation. Short time (high
frequency) solutions emphasize the wave be-
havior; long time (Heaviside expansion) solu-
tions emphasize approach to steady state and
stability. Interpretation of time delays is
straightforward once they are expected. The
effect of time delays on stability can be readily
explained on physical grounds.
Problems arising with parabolic partial dif-
ferential equations are contrasted with hyper-
bolic, wave problems as well as lumped parameter
problems. The t-z diagram of Fig. 1 can also
be used to qualitatively interpret diffusion re-
sponses but with characteristics which are hori-
zontal, corresponding to infinite wave velocities.
The Riemann representation naturally reduces to
the Green's function solution. No delays are en-
countered. For these problems also both short and


long time solutions prove to be useful in inter-
preting the results. Typical example problems
treated in parabolic systems illustrate that real
systems, whether by virtue of Taylor diffusion,
axial disperson or whatever means, never achieve
the ideal limiting behavior of hyperbolic systems.
A physical interpretation of the effect of super-
imposing a small amount of diffusion into a purely
wave response is then given.


/ /
/ M(C,r) /
/ /
I / +/V
P I,,',uL i .J '," BOUNDARY AND
rl .r-aTa *,jLj I

-T- ---

T" ,vi

T2 IV 2

Fig. 1. Domains of dependence on initial and boundary data-double
pipe heat exchanger.
The above problems all arise from linear con-
stant coefficient distributed parameter models.
Much can be said in general about variable co-
efficients and nonlinear problems. The former are
treated by first transforming and making the
change of variable to the corresponding Riccati
equation. This illustrates the very real problem
that although linear and transformable, distri-
buted parameter systems do not always even yield
transfer functions, let alone meaningful expres-
sions for time responses. Several well known
problems which can be solved are illustrated and
discussed in terms of their peculiar characteris-
tics. Strictly nonlinear or semilinear problems
are treated in much less detail. Examples of solu-
tions by the method of characteristics and per-
turbation techniques are discussed. The para-
metric pumping concept is a useful illustration.
In view of the general complexity of dis-
tributed parameter problems when solvable and
the real possibility that some linear problems
cannot be solved, approximation methods are

Rather than following one wag's assessment that,
having lost control, one teaches process dynamics;
it is useful to teach process dynamics,
without control.

given special emphasis here. Available tech-
niques such as quantization, the method of mo-
ments, modal approximation, successive approxi-
mations and asymptotic approximations are all
introduced. Typical sample problems are used to
illustrate the low frequency applicability of the
first three and the high frequency utility of the
last two. The value of the approximations are
judged in terms of their utility in frequency re-
sponse, time response as well as the general phy-
sical interpretation of responses.

I N VIEW OF THE expressed intention of
applying process dynamics to as broad a spec-
trum of applications as possible the course con-
tent is evolving gradually as better and more
diverse illustrations become available. Problems
given as assignments are chosen to reflect the
breadth of application. To the extent possible
students are permitted a wide degree of choice
of examination problems and term paper topics
so that special interests can be accommodated.
One interested in control problems can specialize
his applications just as one interested in reactor
design and technology. Perhaps this breadth of
interest is reflected by the following selected term
paper titles: 'Noninteracting Control of Distilla-
tion Columns," "Analysis of the Filtration of a
Puff of Cigarette Smoke," "Relation between
Singular Perturbations and System Simplifica-
tion," "Analysis of an Electro-hydraulic Valve,"
"Thermal Regulation in the Human Body," and
"Physical Interpretation of the Oscillatory Sta-
bility Criterion in a Stirred Tank Reactor."
Process dynamics is a subject of infinite
variety. Like transport phenomena it consists of
a core of fundamentals applicable to diverse sit-
uations. Dynamics is not synonomous with con-
trol. "Processes" maybe interpreted as a piece
of equipment in a plant, a single molecule, or the
human body. The underlying principles of pro-
cess dynamics are common to all applications. A
combination of a unified treatment of these
fundamentals and illustrative examples of appli-
cations in a range of fields is the intent of this
course. Rather than following one wag's assess-
ment that, having lost control, one teaches pro-
cess dynamics; it is useful to teach process dy-
namics, without control.



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Master University, and P.T. Shannon
of Dartmouth College. Describes and
illustrates the strategy of simulation to
answer technical questions about non-
linear processes with realistic objec-
tives and industrial data and restraints.
Demonstrates the technique with the
sulfuric acid plant, and discusses other
experiments such as those which in-
volve pulp and paper processing, alkyla-
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systems and various petrochemical
processes. May 1971 330 pp. $16.95

Meissner, Massachusetts Institute of
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and quantitative study of factors de-
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ing chemical transformations. Simi-
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indicated, depending on whether the
reactions occurring are homogeneous
gas phase, gas-solid, gas-liquid and the
like. Problem emphasis is on the syn-
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given to the total operation rather than
only to the reactor and its design.
January 1971 386 pp. $14.95 (72332-0)

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Naturally chemical engineers need all the education they can get. At Mobil
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The 20th edition of the Committee's widely dis-
tributed publication, CHEMICAL ENGINEER-
ING FACULTIES, has been published at the
University of Texas under the guidance of David
Himmelblau. The directory, which lists faculties
and other information about chemical engineer-
ing departments in the United States, Canada,
Great Britain, and Australia, is published in co-
operation with the national office of AIChE. Cop-
ies are supplied to academic departments and to
Committee members. They are also available for
sale through the AIChE national office.
The Design subcommittee is sponsoring a full
day symposium on "Educational Programs in
Process Design" at the annual meeting in Chica-
go. The subcommittee is chaired by Howard E.
Turner of duPont and C. Judson King of the
University of California at Berkeley. Dr. King is
also responsible for developing a Design Educa-
tion Workshop as part of the 1972 Summer School
for Chemical Engineering Faculty being planned
by the Chemical Engineering Division of ASEE.
The chairman of the subcommittee on Under-
graduate Curricula, Clyde W. Balch, has carried
out a survey on undergraduate design education.
The results of this survey will be reported at the
session mentioned in the previous paragraph.
The subcommittee on One-Day Schools held
a session on "Chemical Engineering in the Phar-
maceutical Industry" at Merck and Company in
Rahway, New Jersey. Sixty-seven faculty mem-
bers from 14 academic departments attended.
While one-day schools continue to be successful in
the Middle Atlantic area, attempts to generate

Various AIChE Committees
concerned with educational mat-
ters have furnished CEE reports
of their activities.

such schools in other parts of the country have
The subcommittee on Graduate Study, C.
Michael Mohr Chairman, has prepared a question-
naire for a survey on outcomes of doctoral pro-
grams. It is hoped to complete the survey in the
year ahead.
The subcommittee on Films has been reor-
ganized with Robert M. Hubbard as chairman. He
is presently active in the development of films
for educational purposes and is trying to estab-
lish contact with other interested persons in che-
mical engineering.
The new subcommittee on Cooperative Educa-
tion has proposed a number of possible directions
for action. The chairman, W. H. Tucker, will lead
a discussion at the Education Projects Committee
meeting in Chicago.
The subcommittee on Chemical Engineering
Laboratory Experiments, W. H. Tucker, chair-
man, has been working with Professor B. E.
Lauer on a new volume of laboratory experiments.
A further survey of colleges is being contem-
plated, as is some coordination with the workshop
on laboratories to be held at the 1972 ASEE Sum-
mer School for Chemical Engineering Faculty.
The chairman of the Programmed Learning
subcommittee, Charles E. Wales, recommends dis-
banding the subcommittee because very few
chemical engineers are writing programmed in-
struction. He feels that this activity can be more
adequately handled by the ERM Division of

C. Judson King, University of California at Berkeley,
became chairman of the Committee January 1, 1971.



Engineering not only serves man but has assumed
a deep responsibility for the effect of its contribu-
tions on society. For the graduate of a well grounder
engineering program, continuing engineering studies

will be essential in order to remain informed and to
retain the ability to make appropriate decisions in this
rapidly advancing technological society. The engineer
must assume the responsibility for maintaining his
competence at the maximum level, but industry, gov-
ernment, universities and professional societies must


provide opportunities for continuing education. on-
tinuing engineering studies are a national obligation
of the entire engineering profession to the progress of
Similar thoughts by a forward looking nation-
al AIChE leadership motivated the initiation of
the AIChE Continuing Education Committee in
1963 under the capable leadership of W. R. Mar-
shall, Jr. From a modest beginning of two pro-
grams the AIChE Continuing Education Program
has now grown to the point where some fifty pro-
grams are annually scheduled in convenient lo-
cations across the country to provide assistance
to chemical engineers with their continuing edu-
cation programs.
TTHE PRESENT AIChE Continuing Education
Program involves four different types of pro-
grams. The Today Series is a tutorial short course
designed to update chemical engineers who have
not had the opportunity to become familiar with
material which is now part of the undergraduate
chemical engineering curriculum but was not so
ten or fifteen years ago. The AIChE Advanced
Seminar is a short course intended for the chemi-
cal engineer familiar in a specific area of chemi-
cal engineering but desiring to learn what is going
on in the research frontiers of the area. The Man-
agement Seminars are designed for chemical en-
gineers who are adequately trained technically
but are now experiencing the need to become more
acquainted with the latest management tech-
niques. Finally, the AIChE Continuing Educa-
tion Workshop individually involves the partici-
pating chemical engineer with both experts in a
certain field and others interested in the same
field. This latter technique has been successfully
employed for subjects like pollution, manage,
ment, computer use, etc.
During the past four years the Committee has,
with the gracious assistance of many dedicated
chemical engineering lecturers, developed thirty-
eight different Today Series, six AIChE Advanced
Seminars and four Management Seminars. (At
least six more programs are currently being con-
sidered by the Committee for 1971.) During 1970,
the Committee sponsored a total of thirty-four To-
day Series, three AIChE Advanced Seminars,
three Management Seminars and one Workshop.
All but three of the forty-eight programs were
two-day programs. These programs have been

**E. Weber, President of The Polytechnic Institute of
Brooklyn, presented at ASEE Continuing Engineering
Studies Conference, Dec. 12-13, 1966, Chicago, Ill.

scheduled principally at AIChE meetings. How-
ever, the more popular programs have also been
scheduled at other locations across the country
often with the support of the local AIChE section.
The list of programs developed by the Committee
includes such topics as mathematical modeling,
simulation, optimization, strategy in process en-
gineering, prediction of design data, automatic
control, transport phenomena, reaction engineer-
ing, catalysis, statistics, statistical design, tech-
nical economics, heat transfer, distillation, poly-
mer processing, instrumentation surface phe-
nomena, air pollution control, water quality con-
trol, legal aspects in engineering, etc. Printed lec-
ture notes for some of these programs are avail-
able from the New York AIChE office at nominal
cost to local AIChE sections desiring to present
these programs to their members.
To more clearly ascertain the specific needs of
chemical engineers in local AIChE sections the
Committee has recently formed a subcommittee
which will poll and interview key representatives
of local sections. This survey will be similar to the
one undertaken by the South Texas section in
1963. However, this survey will go beyond de-
termining the short course developments desired
by various individuals in that it will try to as-
sess what programs should be made available on
the national AIChE level and what programs
should be made available on the local section level.
In addition, the Committee will seek to determine
what types of programs and media are best suited
for individuals of large sections, small sections,
large companies, small companies, etc. Greater
emphasis will also be placed on locating key per-
sonnel in the various local sections who can serve
as focal points for that section's continuing edu-
cation program.
IN LINE WITH TRYING to develop different
types of continuing education programs, for the
varied interests of chemical engineers, the Com-
mittee with the kind assistance of the Union Car-
bide Corporation has just arranged to develop a
three hour video-tape presentation on "Funda-
mentals of Heat Transfer." This program is a
shortened version of a Today Series by the same
name which has been well received by attendees
of the two-day course. In attempting this video-
tape program, the Committee felt that it should
explore the reactions of local section members and
individuals pursuing a variety of continuing edu-
cation programs to determine if this media would
not only fill a need but also be accepted as an ad-


junct to their educational programs. Plans call
for making this video-tape available on a mini-
mal rental fee basis with an accompanying survey
of all viewers of the tape. From comments of the
viewers, the Committee should be able to deter-
mine whether a series of video-tape presentations
should be developed of the more popular programs
in the Today Series.
Because of the gradually increasing need for
continuing education by all chemical engineers,
the Committee has formulated a ten-point pro-
gram to guide it in its future operations. These
Constantly upgrade both present and future continu-
ing education programs.
Increase the quantity of published material from
various continuing education programs.
Develop better techniques for determining the con-
tinuing education needs of AIChE members.
Develop new programs which fill these continuing
education needs of AIChE members.
Assist local AIChE sections with development of
their own continuing education programs.
Increase acceptance of the continuing education con-
cept by industry.
Further the cooperation with continuing education
programs of educational institutions.
Develop closer working relationships with other
professional societies having continuing education
programs of interest to AIChE members.
Continue the exploration of new media to provide
continuing programs in a more convenient and usable
form for AIChE members.
Extend the publicity coverage of both AIChE and non
AIChE continuing education programs of interest
to AIChE members.

Available manpower in the New York AIChE
Office is directly related to the number of continu-
ing education programs that the Committee spon-
sors. This number, during the past two years, has
been established at approximately fifty. The Com-
mittee is, therefore, planning no more than this
number on a national level for both 1971 and 1972.
Greater emphasis will be placed on having the
local AIChE sections develop their own continu-
ing education programs with assistance from the
Committee. The nucleus of available programs is
now sufficient to give the local AIChE sections a
wide variety of choices to satisfy their continuing
education needs. However, as noted above, the
Committee will continue to develop additional
quality programs to meet the ever changing needs
of the AIChE membership.
The Education Projects Committee carries on
projects oriented toward chemical engineering
education. Suggestions for projects come from

various sources. The new activities are initiated
only if an interested person can be found to serve
as chairman of a new subcommittee. The projects
develop at various rates and subcommittees dis-
appear when projects are completed and no fur-
ther work is proposed.

to M book reviews J

Material and Energy Balance Computations.
E. J. Henley and E. M. Rosen. John Wiley &
Sons, Inc. (1969), pp xxx + 577, $14.95.
Henley and Rosen have undertaken a major
task in this book, that of combining the "new
stoichiometry" with the presentation of those
chemical and physical principles and manual cal-
culation methods usually taught in a beginning
chemical engineering course. The "new stoichio-
metry" consists of linear algebra, numerical
methods and machine computations plus some
changes in the traditional ways of formulating
the approaches to problem solutions.
A major judgment is that, to quote from the
Preface, "We recognize that there is more mate-
rial in this book than can be successfully incor-
porated in even a one-year course." It is this re-
viewer's opinion that critical deletion of material
would have better served the authors' aim of a
text emphasizing the new stoichiometry. To cite
only one example, the longest chapter in the book
is that on thermodynamics. Most of this chapter
deals with the second law and related functions,
material not essential to most material and energy
The authors' correctly point out that by select-
ing six of the nine chapters an instructor may
use the text as a classical stoichiometry book. In
this regard, the treatment of some topics is
judged to be less successful than that of some
other basic texts. One example is that major
bugaboo of the beginning course, units and di-
mensions. The section on units and dimensions
dwells more upon what units are not than what
they are, tending to obscure rather than clarify
their nature and use. Another example is that
the presentations and applications of the laws of
conservation of mass and energy do not empha-
size the value of a general (i.e. a word) statement
of these equations as a framework for setting up
the specific equations for a particular problem.
Still another example is that there is only a very
brief treatment of the unsteady-state.

The book is very inclusive in the treatment of
the chemical and physical principles that deter-
mine the behavior of substances in chemical pro-
cesses. There is much material on phase equili-
brium and material and energy balances in staged
systems. The book is liberally supplied with ex-
amples, problems and data tables.
The more likely reason for selecting this book
would be the desire to emphasize the new stoichio-
metry. The three unique chapters, then, are of
special interest. Of these, Chapter 5 deals with
"The Solution of Equations." In this chapter,
methods for solving sets of linear and non-linear
equations are presented. The methods are applied
to given equations, not to process problems in
this chapter. Especially worthy of note is that
an appendix includes complete FORTRAN IV
program listings for four of the methods dis-
cussed. They are: GMST, Gram-Schmidt method
of constructing orthogonal vectors for sets of
linear equations; GELG, Gaussian elimination
method for solving a set of linear equations;
ROOT, finds the root of a one-dimensional, non-
linear equation; and, BSOLVE, Marquardt's
method to solve a set of non-linear equations.
Each program includes the solution to an example
problem from the text. This chapter could be
useful in many contexts for it presents in a
reasonably clear and concise form several useful
algebraic-equation-solving techniques.
Chapter 8 emphasizes developing solution
algorithms for certain process calculations,
namely flash vaporization and equilibrium-
extent-of-reaction in both homogeneous and
heterogeneous systems. This chapter requires a
rather thorough understanding of the principles
of phase-and chemical-equilibria. A number of
excellent examples of problem formulation and
algorithm development are included.
Chapter 9 emphasizes process material and
energy balances by computer process simulation.
The building-block approach is clearly presented.
The contents of the building-blocks tend to be
somewhat obscure. Indeed an example illustrat-
ing the individual block calculations includes a
reactor where conversion is kinetically deter-
mined. The equations cannot be very meaningful
to a student, for nothing in the book has prepared
him for a non-equilibrium chemical reactor.
Chapter 9 presents and compares direct substi-
tution, the quasi-Newton method and an exten-
sion of Nagiev's method of split-fractions for
handling recycle loops. It represents a reasonably
good introduction to the rapidly developing field

of computer process simulation and design. The
level of chapters 8 and 9 would seem to be above
that of a first course, but they contain valuable
material for chemical engineering curriculum.
In summary, this book could be used as a traditional
stoichiometry book. It offers a very thorough treatment of
the physical and chemical bases of material and energy
balances, though in this reviewer's opinion the treatment
of some topics lacks clarity. It offers material unique in
this type of book in the way of the mathematics and the
use of a digital computer for solving sets of equations, the
development of algorithms for certain complex process
operations, and an introduction to computer simulation
of chemical processes. This new material is welcome in
textbook form, though much of it appears to be above the
level of the typical first course.
This book is sufficiently important that all teachers of
chemical engineering undergraduate courses should ex-
amine it. They might choose to use portions of it in
several courses.
Ronald E. West
University of Colorado

"[44 "problems for teachers

Simplified Approach to


University of Houston
Houston, Texas 77004

Q. Derive expressions for polytropic processes.
A. Little attention is given to developing new techniques
for teaching elementary concepts in thermodynamics in
comparison to emphasis on advanced research. When
new methods can be found which simplify and afford
clearer presentation of basic principles, the student can
proceed more rapidly and confidently to advanced aspects
of the subject. The authors believe that one of the surest
methods for providing more time and better understand-
ing of advanced topics arises from improving approaches
to the simpler topics of thermodynamics.
W e have explored a new way of deriving the well-
known expression pV" =- constant, which is straight
forward in approach and appealing to the student. The
proposed method can be restricted to processes, or it may
be broadened to include irreversible effects. The instructor
can take up the simpler reversible case or go into more
depth by treating lost work. While more explanation is
required when friction effects are included, a broader
understanding is produced; and an introduction to ir-
reversibility is commenced.
In the simpler reversible case, the method consists of
assuming that the polytropic specific heat for an ideal
gas is corstant and then deriving the expression pVn =
constant. This procedure is the reverse of that which is
usually encountered in textbooks, where it is first as-
sumed that the expression pVn = constant is valid; and
then the polytropic specific heat is shown to be constant.
In many texts, derivation of pVk = constant for a re-
versible adiabatic process is the first step toward the
more general expression. In the proposed method, the

more general pV" = constant is derived, and it is then
demonstrated that n = k is a special case.
In the second case involving lost work, it is possible
to introduce the concept of a quasi-equilibrium process
with friction, and then derive a more general expression
of the form pVni = constant. The exponent ni reduces
successively to n for a reversible operation and then to k
for the added constraint of adiabaticity.
In the reversible case, the first law of thermodynamics
d'Q = dU + d'W (1)
NCdT = NC dT + pdV (2)
with the assumptions of an ideal gas constant specific
heat, and reversibility. Introducing irreversibility, it is
possible to say
d'W = d'Wr + d'L = (1 r)pV (3)
r w
Various postulates concerning friction are possible. For
our purposes, we assume that the lost work is propor-
tional to the reversible work, because that assumption
leads to the answer we want in the form pVni = constant.
The sign prefixing the factor r is dependent upon whether
the process involves expansion or compression of the
gas as demonstrated in Figure 1.
Prefix r by Prefix r by +

For the irreversible case, the first law becomes
NC.dT = NC dT + (1 r)pdV (4)
where C, is an irreversible specific heat. Utilizing pV -
NRT, the differential dT can be eliminated from Equa-
tions (2 and (4) to give

dV (5)

p C j V-

p L'v-i/l vi vCJ

whose solutions are, respectively,
pV = Constant pVni = Constant


C -C Ic-c. /c-c\
where n P C and ni +=- r C

Various thermodynamic relations for irreversible pro-
cesses can similarly be developed for expansion and for
I T IS POSSIBLE to derive a series of equations for
Q, W, AU, AS, and pVT relationships gased on
Equation (7a,b). For example, the irreversible specific
heat is given by

Ci = Cv 11 rl R (8a)

for expansion and

Ci== C i R (8b)
1 V
for compression. The isobaric specific heat with n1 = 0
Cpi = (1 r)R = C + rR (9)
V p
For r = 1, corresponding to complete irreversibility in
an isobaric expansion,
Cpi = C R= c (10)
For an adiabatic process, the pV relation is
PVk r(k-1) = Constant (11)
When r =1, the process corresponds to an unrestrained
expansion, and the exponent in (11) becomes unity as
The entropy change offers a good opportunity to show
that dS 9 dQ1/T. The first law can be written as
d'Qi = dU + (1 r)pdV (12a)

= dU + pdV rpdV


where Q, is used to emphasize that the heat transfer
occurs in an irreversible operation. The quantity dU +
pdV can be replaced by TdS, thereby leading to

d'Qi d'Lw dT pdV
dS dT- NC ( r) T
Substituting NR/V = p/T leads to
AS = NCiln(T2/T,) ( r)NRln(V2/V )
For an adiabatic process, (14) reduces to
AS = rNRnV 2/VI




for an expansion.
It is possible to have an isentropic expansion which
is not reversibly adiabatic. By placing AS = 0 in (14),
manipulation leads to

(jr)Cijv2 r (16)

as the condition




for an isentropic process.

Reversible polytropic specific heat
Irreversible polytropic specific heat
Reversible specific heat at constant
Irreversible specific heat at constant
Specific heat at constant volume
Adiabatic exponent
Lost work
Reversible polytropic exponent
Irreversible polytropic exponent
Heat transferred
Heat transferred in irreversible process
Irreversibility factor
Universal gas constant
Internal energy
Reversible work


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