Plant design for undergraduate chemical engineers
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0 PLANT DESIGN FOR UNDERGRADUATE CHEMICAL ENGINEERS MAX S. PETERS The University of Illinois, Urbana, Illinois Om modern methods of engineering education involve exposing the u~dergraduate student to a wide variety of subjects. As the education process proceeds, the courses become more and more specialized until the student finally emerges as a mechanical, electrical, chemical, or other type of engineer. In many cases, the undergraduate engineer finishes his university training with a good grasp of the information presented in the individual courses he has taken, but he has not had the opportunity for a composite application of his knowledge. This situation may be remedied for the undergraduate chemical engineer by including a com- prehensive plant-design course in the senior-year pro- gram. The undergraduate chemical engineer takes courses in mathematics, calculus, English, chemistry, electrical and mechanical engineering, foreign languages, stoi- chiometry, unit operations, and industrial technology along with other related subjects. Each of these sub- jects is important within itself, but, before the student is sent out with a degree in chemical engineering, he should be given a chance to interrelate the various phases of his training. The course in chemical engi- neering plant design is ideal for this purpose. If the course is taught correctly, it finally gives the student a chance to apply the mass of theory that has been thrown at him for almost four years. Many of the seniors en- ter the plant-design course as boys fumbling with a variety of information which they are not too sure is practical, and they emerge as men confident of their ability to be real chemical engineers. Despite the obvious importance of the rounding-off course in plant design, many of our universities are graduating chemical engineers with no course of this type included in their training. Some schools attempt to make up for this deficiency by including subjects such as economics or having the students work one plant design problem a3 a part of their industrial teeh- nology course. These substitutes are inadequate and an injustice is being done to the students and to the industrial concerns which hire these men. The instruction in a good plant-design course should be handled by a chemical engineer who has had in- dustrial experience or, at least, strong contacts with industry so that he realizes the over-all type of work the students will be in when they leave the university. The instructor should recognize the importance of pre- senting the subject matter so that the students have the opportunity to develop a practical concept of chemical engineering and its applications. 61 ECONOMICS In this modern age of industrial competition, the engineer must realize that his work will he judged on the basis of its monetary return as well as its theoretical soundness. For this reason, the practical engineer should have a basic knowledge of economics. Since plant design is, in reality, the practical application of chemical engineering principles, it would be impossible to discuss plant design without also including economics. Some of our chemical engineering schools have tried to present economics as a subject independent of plant design. While such a treatment is better than no course at all, much of the value is lost since the emphasis is ordin&ly placed on pure economics rather than on the combination of economics with theoretical principles to give practical results. In chemical engineering work, economics and plant design are so closely interrelated that it is always advisable to consider economics and plant design as one combined subject. METHOD OF PRESENTATION The ideal plantdesign course consists of a series of integrated lectures and practice sessions combined with one major design problem of practical significance. Two or three one-hour lecture sessions per week permit the instructor to present the important information on economics and plant design. A weekly three-hour prac- tice session is very valuable for solidifying the students' understanding of the information presented in the lec- tures. The practice session should be used for class dis- cussion and solution of typical problems related to the lectures and discussions. Since the purpose of this course is to round off the students' training and pre- pare them for the industrial approach to chemical en- gineering, these practice-session problems should not be of the usual academic type. The problems should be completely practical and the economic implications should be strongly emphasized. The students should work on the problems in groups of two or more so that they can get the feeling for sharing ideas and cooperat- ing with their fellow workers. The practice sessions with the accompanying class discussions and problems are essential to a good plant- design course. The lectures by themselves would not he sufficient to achieve the goal of the course. How- ever, the lectures combined with the practice sessions give the students a chance to listen to the general in- formation, discuss it, and then apply it. One major plantdesign problem should also be 9
Transcript of Plant design for undergraduate chemical engineers
0 PLANT DESIGN FOR UNDERGRADUATE CHEMICAL ENGINEERS
MAX S. PETERS The University of Illinois, Urbana, Illinois
Om modern methods of engineering education involve exposing the u~dergraduate student to a wide variety of subjects. As the education process proceeds, the courses become more and more specialized until the student finally emerges as a mechanical, electrical, chemical, or other type of engineer. In many cases, the undergraduate engineer finishes his university training with a good grasp of the information presented in the individual courses he has taken, but he has not had the opportunity for a composite application of his knowledge. This situation may be remedied for the undergraduate chemical engineer by including a com- prehensive plant-design course in the senior-year pro- gram.
The undergraduate chemical engineer takes courses in mathematics, calculus, English, chemistry, electrical and mechanical engineering, foreign languages, stoi- chiometry, unit operations, and industrial technology along with other related subjects. Each of these sub- jects is important within itself, but, before the student is sent out with a degree in chemical engineering, he should be given a chance to interrelate the various phases of his training. The course in chemical engi- neering plant design is ideal for this purpose. If the course is taught correctly, it finally gives the student a chance to apply the mass of theory that has been thrown at him for almost four years. Many of the seniors en- ter the plant-design course as boys fumbling with a variety of information which they are not too sure is practical, and they emerge as men confident of their ability to be real chemical engineers.
Despite the obvious importance of the rounding-off course in plant design, many of our universities are graduating chemical engineers with no course of this type included in their training. Some schools attempt to make up for this deficiency by including subjects such as economics or having the students work one plant design problem a3 a part of their industrial teeh- nology course. These substitutes are inadequate and an injustice is being done to the students and to the industrial concerns which hire these men.
The instruction in a good plant-design course should be handled by a chemical engineer who has had in- dustrial experience or, a t least, strong contacts with industry so that he realizes the over-all type of work the students will be in when they leave the university. The instructor should recognize the importance of pre- senting the subject matter so that the students have the opportunity to develop a practical concept of chemical engineering and its applications.
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ECONOMICS
In this modern age of industrial competition, the engineer must realize that his work will he judged on the basis of its monetary return as well as its theoretical soundness. For this reason, the practical engineer should have a basic knowledge of economics. Since plant design is, in reality, the practical application of chemical engineering principles, it would be impossible to discuss plant design without also including economics.
Some of our chemical engineering schools have tried to present economics as a subject independent of plant design. While such a treatment is better than no course at all, much of the value is lost since the emphasis is ordin&ly placed on pure economics rather than on the combination of economics with theoretical principles to give practical results. In chemical engineering work, economics and plant design are so closely interrelated that it is always advisable to consider economics and plant design as one combined subject.
METHOD OF PRESENTATION
The ideal plantdesign course consists of a series of integrated lectures and practice sessions combined with one major design problem of practical significance. Two or three one-hour lecture sessions per week permit the instructor to present the important information on economics and plant design. A weekly three-hour prac- tice session is very valuable for solidifying the students' understanding of the information presented in the lec- tures. The practice session should be used for class dis- cussion and solution of typical problems related to the lectures and discussions. Since the purpose of this course is to round off the students' training and pre- pare them for the industrial approach to chemical en- gineering, these practice-session problems should not be of the usual academic type. The problems should be completely practical and the economic implications should be strongly emphasized. The students should work on the problems in groups of two or more so that they can get the feeling for sharing ideas and cooperat- ing with their fellow workers.
The practice sessions with the accompanying class discussions and problems are essential to a good plant- design course. The lectures by themselves would not he sufficient to achieve the goal of the course. How- ever, the lectures combined with the practice sessions give the students a chance to listen to the general in- formation, discuss it, and then apply it.
One major plantdesign problem should also be
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included in the course program. The class may be given one or two months for the solution of this problem, and it should be given during the last part of the course. This major problem should be based on a practical in- dustrial process, and it should involve a large amount of logical thinking as well as chemical engineering, eco- nomics, and plant-design principles. The short proh- lems in the practice sessions give the st.udents rounded ability in the various types of design applications while the major problem proves to the student that he can tackle a difficult chemical engineering subject and fol- low it through to completion.
The success of the chemical engineering plant-design course rests squarely on the shoulders of the instructor. Dr. L. E. Stout, Dean of Engineering a t Washington
Outline of Essential Dlateriel to be Covered in the Plant Desion Courae
I. Elementary Economic Considerations A. Costs'
1. Fixed costs 2. Direct production costs 3. General plant overhead 4. General sdministrstive and office overhead 5. Distribution costs 6. Contingencies
B. Investments 1. Fixed capital investment 2. Working capital investment 3. Total investment Depreciation 1. Obsolescenoe, service life, depletion, and scrap
value 2. Straight line method for determining depreciation 3. Reducing balance method for determining depreci-
atlon 4. Sinking fund method for determining depreciation
D. Return on investments E. Investment eampclrisons F. Cost estimates
1. Order-of-ma~nitude estimates 2. Preliminary estimates 3. Firm estimates 4. Labor and material indexes 5. Multidication factors
11. Generd Design Considerations A. Bateh versus continuous processes B. Insurance, health and safety requirements C. Fabrication of eqkipment D. Materials of construction E: Pitents F. Plant location G. Designs far special equipment H. Instrumentation I. Waste disposal J. Structural design
111. The Desim Project A. Prell'minarji designs B. Detailed estimate designs C. Firm nroeess desiens
E. Literatlire surveys F. Comparison of different processes G. Flow diagrams H. The desien reoart .> .
IV. Design Calculations and Methods A. Transfer of materials B. Heat transfer C. Mass transfer D. Chemical kinetics in design E. Miscellaneous
University, St. Louis, has made the following statement: "Few, if any, college professors are sufficiently well in- formed on industrial practices to teach a course in chemical engineering design which commands the re- spect of practicing engineers. . . . "' If this statement is correct, the teaching staffs of our chemical engineering schools are not adequate for the task of preparing our young men for gradkitiou with degrees in r h ~ m i r d en- rrineeriw. So coed srl~ool ~ l i ~ u l d C O I I P ~ ~ ~ itsellveonble - " - of granting bachelor's degrees in chemical engineering unless it has a t least one man on its staff with sufficient practical experience and understanding of industrial methods to permit him to present a respectable design course. The main point which Dr. Stout intended to bring out in his statement was that outside lecturers should be brought in from industry for the course in plant design. This suggestion has a great deal of merit and should be followed if at all possible. However, this does not mean that the entire course should be given over to a series of lectures by various industrial "experts" although this method has been used by some of our chemical engineering ~chools.~ A good plant- design teacher can organize his lectures so that a fine continuity runs through the entire course. If the classes are occasionally given over to appropriate talks by capable men from industry, the students will bene- fit from the direct contacts with industrial ideas and practices. These outside lectures can be arranged to fit in with the subject matter previously treated by the instructor and the new viewpoints will serve as an ideal balance for the course.
OUTLINE OF COURSE
The subject material which should be covered in the plantdesign course can be broken down into four gen- eral headings as follows:
I. Economic considerations. 11. General design considerations.
111. The design project. IV. Design calculations and methods.
The table presents an outline of the important suh- jects that should be included under each of these four general headings.
A treatment of chemical engineering economics should be presented at the beginning of the course. This gives the students an introduction to the financial side of chemical engineering and permits an immediate visuali- zation of the essential profit problems facing all indus- trial concerns. The various types of costs involved in industry along with methods for estimating these costs should be considered. Investments and return on investments are of particular importance and these two topics should be covered thoroughly before any design problems are attempted.
To present the over-all picture of plant design, it is necessary to include a number of specialized topics such as plant location, waste disposal, patents, and others
1 S T O ~ L. E., Am. Soe. Eng. Educ. address, June, 1951. 3 N ~ c n o ~ s , W. T., Chem. Eng. Prog., 48,201 (1952).
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methods and problems of industry become something Too many of our schools are graduating chemical tangible. After the student, following many stops and engineers without tying their training together and starts, finally completes the major design problem, he preparing them for industry. A good course in plant becomes a man confident of his ability to take his place design will remedy this situation. I t isup to our chem- in industry as a chemical engineer. ical engineering schools to supply such a course.
