In the Classroom
An Industrial Chemistry Course That Optimizes the Value of Plant Tours J. Stephen Hartman Department of Chemistry, Brock University, St. Catharines, Ontario L2S 3A1, Canada;
[email protected] The need for introducing chemistry students to the industrial applications of chemistry has been addressed in various ways (1, 2). Many chemistry departments offer a course in industrial chemistry, which can be aimed at students at any level from year one (3, 4) to year four and graduate level (5–7), and entire programs can have an industrial chemistry orientation (8, 9). Industrial chemistry courses can involve a wide range of formats: lectures plus class presentations, sometimes with emphasis on business aspects (7, 10, 11), lectures plus labs (1), or various combinations including features such as visiting speakers from industry (2, 12). Frequently, but not always, some use is made of visits to local chemical industries, that is, plant tours. “Students in tertiary education are effectively cocooned from the real world” (2, online abstract). A visit to an industrial chemistry site injects a much needed element of reality, since many students in traditional academic chemistry programs have no sense of the huge scale of modern chemical industry. The first tour of a major production facility is an
eye-opening experience for most students in an industrial chemistry course and, for some, it is mind-boggling. However plant tours, if done in isolation from other aspects of the course, can easily become merely a “gee whiz” experience for many students: a tourist experience with little long-term influence on how they think about chemistry. They can go on the tour and be impressed by the size of the operation, but still go home little the wiser. If plant tours are seen by students as an optional extra, an outing with hopefully some entertainment value, their value as a teaching tool is reduced and a number of negative effects can show up, such as students chattering to each other during the tour instead of being attentive to the tour guide. In our year three industrial chemistry course at Brock University I have experimented with ways to avoid the “tourist syndrome” in plant tours by getting the students more deeply involved in the process. I focus first on the plant tours and then on the course as a whole and how the tours are integrated into the overall course pattern.
Brock University Department of Chemistry Chemistry 3P60: Plant Tour Reports Visits to chemical plants are an important part of the course and take the place of laboratory work in other chemistry courses. Plant tour reports are therefore analogous to laboratory reports in other courses. Plant tour reports will be submitted in two parts: (i) Literature search: “Pre-tour report“, to be handed in before the tour A brief report on the chemistry involved in the process, and anything else from the literature that you find interesting and relevant (e.g., statistics on quantities produced; nature of the equipment normally used). One or more literature references on the process (e.g., from The Kirk–Othmer Encyclopedia of Chemical Technology) should be included. (ii) Plant Tour Report: to be handed in within a week, following the tour An account of the student's own observations of the plant. This should demonstrate an understanding of the process and of the way the particular plant functions. It should not be just a copy of the instructor's material or a company handout, although company handouts and flow charts can be included, perhaps in an appendix. This is a report on the specific chemical plant and process observed, which may differ significantly from information available in the literature (part i of the report). Describe any such differences. Key equations and a brief outline of the process should be included; use flow charts when possible. Some or all of the following might be included. Not all of these will apply in every case, and some information may be restricted. 1. Description of the source and quality of the raw material used. 2. Quantity of product produced from a given quantity of raw material; total output of the plant. 3. Description of the equipment and chemical process. (How closely is process control achieved; what sort of analyses are carried out, and at what stages of the process?) 4. Pollution control measures. (The student's own impressions of the trapping and disposal of by-products) 5. Economic viability. (Is this plant in danger of losing out to more advanced technologies elsewhere?) 6. Possible improvements. (Is the plant state-of-the-art; what could be done differently if it were being designed now?) 7. Quality of the work environment. (What would it be like to work there? Are there aspects that could be improved?) Figure 1. Student handout describing the plant tour report guidelines.
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The Plant Tours The plant tours have three components: (i) submission before each tour of a brief, preferably single-page, “pre-tour report” based on a literature search, including at least one literature reference; (ii) the tour itself; and (iii) submission one week later of a more extensive “post-tour” report, analogous to a lab report in laboratory-based courses, which emphasizes the chemistry of the process, whether the process is in accord with expectations based on the pre-tour literature search, and with a major emphasis on the student’s own personal impressions of the facility. The guidelines given to the students are shown in Figure 1. The tours and tour reports are an integral part of the course and together count for a significant fraction of the course grade.
The Pre-Tour Report The students know in advance what type of industrial process is involved. They are required to go to the library or the Internet to find information on the industrial process and to hand in this information before the tour. In the first week there is an intensive session on how to use the library to find industrial chemistry-related information, and this background is helpful in finding information for the pre-tour reports. Often The Kirk–Othmer Encyclopedia of Chemical Technology (13) is sufficient. The pre-tour report is a key element because it ensures that the students have already thought about the process before the tour, so they are much more ready to ask penetrating questions during the tour. They tend to pay closer attention and seem to be better able to retain the information. Sometimes the process that we see at the plant is not the same as the one described in the literature sources that the students have found and this, itself, has educational value. There is more than one way to manufacture a product and questions arise naturally of why a particular process has been chosen over other possibilities. This leads naturally to thoughts about changing technology, the fact that many industrial chemistry literature sources are not up to date, and the advantages to companies of keeping knowledge of some advances in technology proprietary. Grades are not assigned to the pre-tour reports. They are returned to the students, with comments added if appropriate, to be resubmitted without modification as an appendix to the post-tour report. The students are not penalized if the process they find in the literature is not the same as the one we actually see at the plant, but they are expected to comment in their post-tour reports on any major differences between the actual process and the one described in the pre-tour report. In recent years it has become necessary to specify that the pre-tour report should be about the industrial process, rather than about the company to be visited. Otherwise pretour reports tend to consist of slick public relations material from the company Web site, with little or nothing about the actual chemistry and process equipment involved. The Tours We are fortunate that a variety of chemistry-related industries, old and new, and light and heavy, are located in the Niagara Peninsula of Ontario. Whenever possible we choose industries that are located within a one-hour drive from Brock www.JCE.DivCHED.org
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University. All of the plants we currently visit fit this criterion and carpooling has worked well. Along with numerous possibilities we do have some constraints: no oil refineries and a steel industry that does not normally allow tours. However, I invite one of our graduates who is employed in the steel industry to come to Brock University and give a technical presentation in place of a tour. Our region includes a thriving but relatively small-scale wine industry. We visit a winery partly for its contrast to the other industries but also for its connection to Brock University’s new Biotechnology and Oenology兾Viticulture programs. (Some of the students in the industrial chemistry course are biotechnology majors.) The large-scale facilities that we visit include a polyvinyl chloride production plant and a paper mill where production is totally based on newsprint and magazine recycling. Table 1 shows a typical group of tours and how they are interspersed with workshop and seminar sessions during the one-semester course. Most companies, when approached about setting up a tour, are supportive once the technical nature of the course is made clear, and provide a technically knowledgeable person to act as tour guide. This individual is usually a chemist or chemical engineer in a responsible position such as chief chemist, quality assurance manager, health safety and environment manager, or even plant manager. The format of the tour is worked out in collaboration with our host. Normally there is an initial presentation, sometimes with video clips and other aids, followed by a question and answer session, then the tour. Often a handout is provided to the students. There is usually a chance for further questions after the tour, especially when touring noisy facilities such as the paper mill where it is difficult to communicate during the tour.
Table 1. A Typical Seminar and Plant Tour Schedule Week
Tour or Seminar
01
Library workshop on the literature of industrial chemistry; Introduction to mass balance calculations
02
Plant tour: Oxyvinyls Canada Inc., Niagara Falls (polyvinyl chloride production)
03
Plant tour: St. Gobain Technical Fabrics, St. Catharines (fibreglass reinforced fabrics)
04
Workshop on mass balance calculations
05
Plant tour: Brock University's thermal storage– cogeneration plant; Introduction to industrial safety
06
Plant tour: Inniskillen Wines, Niagara-on-the-Lake (winery)
07
Plant tour: Abitibi Consolidated, Thorold (paper mill)
08
Student seminar presentations on safety
09
Plant tour: Cytec Canada Inc., Niagara Falls (phosphine chemicals)
10
Student seminar presentations on essay topics
11
Plant tour: INCO, Port Colborne (electrolytic cobalt refinery)
12
Plant tour: Casco, Port Colborne (corn starch and other corn products)
13
Presentation: steelmaking using the basic oxygen process
NOTE: As offered January to April 2003.
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Field Trip Safety – Brock University Department of Chemistr y In accordance with policy of the Faculty of Mathematics and Science at Brock University, the Department of Chemistry has established several principles and procedures that are designed to secure the health and safety of students and faculty while engaged in teaching or research activities at locations away from the Department on field trips. The extent and complexity of field trips vary considerably from afternoon sessions conducted at sites on university property, to extended periods of absence away from the university for work at local field sites. The sections listed below apply to all these cases with the understanding that more extensive precautions might be necessary under some circumstances. By receiving this sheet, it is understood that the receiver has read the contents, agrees to abide by the regulations stated herein, and will take full personal responsibility for his or her actions while on field trips associated with teaching or research work at the university. Basic Safety Regulations for Plant Tours in Chemistr y 3P60: 1. The instructor should advise all students that the trip is part of the course and that as adults they are expected to act responsibly. 2. Footwear and clothing should be in good condition and suitable for the working conditions. Open-toed, woven fabric, or high-heeled shoes are not appropriate footwear. 3. Safety equipment such as hard hats, safety glasses, and earplugs, as provided by the staff of the companies visited, must be worn as directed. 4. Each individual is responsible for always being prepared and aware of potential hazards and alert to maintaining appropriate safety precautions. This includes, for example, holding onto railings while ascending and descending stairways and taking appropriate care while walking along catwalks. 5. Whether or not group transportation is made available for a class, students have the option of using their personal vehicles to reach the tour site. Students who get to the site using their own vehicles, and other students who may be riding with them, are responsible for following the rules of the road and the laws of Ontario. This includes having a valid driver’s license, current car insurance, and a vehicle in safe condition. 6. Any accident, however trivial, should be reported as soon as possible. Figure 2. Student handout summarizing the safety regulations for plant tours.
In the question and answer sessions the value of the pretour report becomes evident. Because the students arrive at the plant already having some understanding of the process, the questioning tends to be more astute and the level of discussion tends to be high. The requirement to write a posttour report, and having the background from pre-tour report preparation to ask appropriate questions, provides a strong focus to the tour itself. The students quickly realize that it is far easier to write a tour report if the tour guides have been drawn out on a number of topics, and a lot of note-taking goes on as the tour guides enlarge on various points. No doubt the initial motivation for many questions is to get good grades on the tour reports, but the inherent novelty of the processes, and especially the expertise and enthusiasm of our tour guides when enlarging on the processes, generates genuine interest. We are very dependent on our hosts. The expertise and enthusiasm of the tour guides is important in motivating these
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sessions. The students appreciate the opportunity to talk to someone with major responsibility for a large-scale process, and the discussion often runs far beyond the actual industrial process into general aspects such as market conditions in the industry and the constraints under which the company operates. Our guides appear to enjoy the opportunity to discuss technical aspects of their work with technically knowledgeable students. Class size has been optimum, not exceeding 15 students in recent years, simplifying the logistics of plant tours as well as seminar and workshop sessions. An instructor planning plant tours should ensure that liability for accidents, either in transit or at the plant, is dealt with in some way. If carpooling is used, it is important to cover the requirements for students who are driving and for those who are passengers. Before the first plant tour I emphasize the requirement to behave responsibly and I distribute a summary of safety regulations for plant tours (Figure 2).
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The Post-Tour Report The “post-tour” report is analogous to a lab report in laboratory-based courses, and helps to ensure that the information gained on plant tours is retained and consolidated. The report emphasizes the chemistry of the process, the equipment involved, and the student’s impressions of the site. See Figure 1, which enlarges upon the tour report guidelines proposed by White (14 ). Labs versus Plant Tours The course as originally set up in 1979 had a weekly three-hour laboratory session in addition to three hours of lectures, with about four plant tours replacing lab sessions during the term. There was a lab grade, but no tour reports or grading related to the tours. Our initial concept was to simulate the lab environment in industry, but this was not straightforward in practice. Laboratory work in industry tends to involve repetitive procedures and there is a strong economic incentive to simplify them so they can be automated or done by staff who do not have formal chemical training. At the other extreme are major troubleshooting operations. Neither extreme fit well into our course. Labs can and do work well in industrial chemistry courses (1) and it is also possible to base a course on case studies of troubleshooting in industry (3), but our choice was to jettison the labs and put increased emphasis on plant tours along with workshops and seminar presentations. Employment Advantages for Students The introduction to local industries has been helpful to some of our students in finding summer employment. Moreover, a plant tour is commonly part of the interview process for a permanent position in industry. Our students, who have become accustomed to asking intelligent questions about industrial processes, tend to make a very good impression.
Table 2. A Typical Lecture Outline Week
Topic
01
Introduction: chemical processing ideas including batch versus continuous processes, unit operations, flow charts, profitability, et cetera
02
Free radical chemistry; introduction to polymer chemistry; polymer industries; condensation and addition polymers
03
Polyethylene; thermoplastics versus thermosets; plastics fabrication and recycling; petroleum refining: fractionation of crude oil
04
Petroleum refining (continued): free radical reactions and cracking; the chemistry of combustion; internal combustion engines
05
Catalytic cracking and petrochemicals; municipal water quality and emission control
06
Fermentation industries: wine and beer; biotechnology
07
Pulp and paper
08
Air quality and emission control; high temperature chemistry: slags, Lux acids and bases, methods of generating high temperatures
09
Heat exchangers; types of electric furnaces; high temperature industries: ceramics
10
High temperature industries (continued): refractories and abrasives; metals and metallurgy: ores and reducing agents
11
Metal oxide reduction at high temperatures; metallurgical industries, emphasizing iron and steel
12
Corrosion; refining of aluminum and nickel; new industrial materials and composites
13
Fuels and energy: prospects for the future. A survey of the strengths and weaknesses of possible energy sources: coal, nuclear fission, nuclear fusion, wind, and solar energy
NOTE: As offered January to April 2003.
The Course as a Whole
Lecture Topics It is important to set the context of the course at the start: how industrial chemistry differs from academic benchscale chemistry. A major theme is “what a chemistry graduate should expect to find, once he or she gets out into industry”. I start by emphasizing aspects such as economies of scale and profitability; a comparison of batch versus continuous processes and why industry so often chooses continuous processes; the importance of flow charts in continuous processes; economic constraints and why “dumping” occurs; and so forth. Such topics are central to most industrial chemistry courses and the introductory chapter of Hocking (15), our course text, provides excellent background reading, as do many other industrial chemistry textbooks (14, 16–18). These concepts are immediately reinforced by our first plant tour. The content of industrial chemistry courses varies widely because the basic ideas of industrial chemistry can be illustrated in a huge variety of specific industrial processes. All industries chosen for study should be important economically and illustrate important general principles. Petroleum, petrochemicals, and the steel industry are so central to the
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modern economy that I include these topics regardless of the possibility of plant tours. Beyond this core, I choose topics with plant tours in mind, maintaining a balanced and diverse selection, and emphasizing wherever possible topics that are not adequately covered elsewhere in our undergraduate curriculum, such as polymer chemistry. A typical lecture outline is given in Table 2.
Essay and Seminars Each student submits a major essay that can be on any industrial chemistry topic not covered in the course or, when appropriate, on a personal experience in the chemical industry. Each student also presents a 10–15 minute seminar to the class, based on his or her essay topic, and fields questions from the audience. The seminar grade is based on participation in other students’ question sessions as well as on the student’s own presentation. Some of the most interesting essays and presentations have been by mature students who have worked in industry, and by students who have had part-time or summer jobs in industry that give them a different perspective. Such students may not be strongly academically inclined, but they are en-
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In the Classroom
livened by the chance to speak about their own real-life experiences. Their presentations are often outstanding, and it is gratifying to see their self-confidence grow as they handle the discussion following the presentation. Students need practice and advice in presenting seminars. Some have never presented a seminar in a university course and, for best results, it is helpful to provide a practice seminar session, a low-anxiety warm-up session, two weeks before their major presentation. This initial short seminar is on an industrial safety-related topic. By this time we have done tours of large-scale facilities, notably the polyvinyl chloride plant where large quantities of flammable and carcinogenic monomer are stored, and the students have become aware of safety issues at a gut level. I first introduce industrial safety, including a lesser known “horrible example” of what can happen when safety is neglected, and following this the students choose any aspect of industrial safety from sources which I provide (19). Chemical plant disasters, and how to avoid them, always generate interest and students frequently choose well-known disasters such as Bhopal. Presenting these intelligently requires appreciable background reading. Many lesser-known categories of hazards are well summarized by Kletz (19a) and choosing a topic from such a source is itself of educational value. For those who wish to dig deeper into the topic of safe design, I recommend books by Petroski (20), which are not chemistry oriented but provide a more general approach to the creative processes and the pitfalls in the design of major structures, and provide a number of thought-provoking tragic cases involving design errors, as well as success stories of innovative design. The safety seminar session is an effective way to deal with the important safety aspect of industrial chemistry, while serving as an “ice-breaker” to get the students accustomed to giving presentations and asking questions.
Following the workshop, simple mass balance problems are assigned in small doses over the next several weeks. There is always a mass balance calculation on the term test and on the final examination, representing about 10% of the test and exam grade. Many excellent examples of mass balance problems are available in sources such as Clausen and Mattsen (16) and Geankoplis (22).
Workshops and Assignments A “library lab” workshop is very useful in the first week, to show students how to find chemical information efficiently in the library. A library tour with emphasis on the reference section is followed by a “scavenger hunt” type of exercise in which each student is assigned individualized questions on practical aspects of chemistry, to be handed in at the end of the session (sample question: “What is the source and alcohol content of tequila?”). The instructor is present, fulfilling a role analogous to that of lab demonstrator, helping to resolve difficulties as they occur. The workshop is followed by a library assignment, to be handed in a week later. Many students do not fully grasp the difference between batch and continuous processes until the three-hour workshop on mass balance calculations for continuous processes, normally in week 3 or 4. Time constraints limit our consideration of such calculations but it is important that students work through at least a few problems to get a feel for continuous processes. Even setting up a flow chart of a continuous process is difficult for some, and can be a useful class exercise (21). Some students have great difficulty with mass balance calculations. Their conceptual difficulties seem to be on a par with those that need to be overcome to solve ionic equilibrium problems. A workshop format with individual help available is the best approach when the students first encounter such problems.
Plant tours, when emphasized appropriately and fully integrated into an industrial chemistry course, are very useful in motivating students and deepening their understanding of the chemical industry. At Brock University the requirement for both pre- and post-tour reports has helped to achieve full integration. The pre-tour report in particular appears to be an important feature in the students taking ownership of the learning process. Most chemistry majors are exposed to very little of the chemistry of industrial processes, and may experience culture shock when they go into industry and find a very different rationale and mode of operation. Our emphasis on plant tours adds immediacy and a practical flavor to the course and is a good preparation for our graduates who move from university to industry.
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Writing Requirements and Course Load The requirement for frequent tour reports addresses a deficiency common in academic programs in many disciplines: too little practice in writing, with resulting weaknesses in communication skills. The “Writing Across the Curriculum” movement advocates making writing more central as a vehicle for active learning (23), and attempts have been made to increase the quantity of writing within chemistry courses (24–26). The industrial chemistry course provides a good opportunity to tackle this problem. However the development of writing skills requires time and effort. Our students typically are enrolled in several courses, and the writing requirement increases the course load so that many students feel overworked. Having to write six or seven full-scale tour reports during the term, plus corresponding pre-tour reports, is not popular with the majority of students who are not efficient writers. I emphasize to them that frequent report writing is one of the real-life aspects of the course as report writing is a valuable skill in industry, and employers frequently complain that recent graduates have inadequate writing skills. It is encouraging that in their course evaluations, even those students who feel overloaded have very positive things to say about the plant tours, which are the single most appreciated part of the course. Conclusions
Acknowledgments I thank the many individuals in various Niagara Region chemical industries who have given generously of their time to act as tour guides for our students, and the companies for hosting us on their premises. I also thank those who participated in developing Brock University’s Industrial Chemistry course: Mary Frances Richardson, Jack M. Miller, and the late Gordon R. Finlay and Herbert L. Holland. A number of students and former students have provided useful suggestions for plant tours and other aspects of the course as it has evolved.
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& Sons: New York, 1986; 2nd ed.; VCH Publishers: New York, 1992. (a) Kletz, T. A. What Went Wrong? Case Histories of Process Plant Disasters, 2nd ed.; Gulf Publishing Company: Houston, TX, 1988. (b) Withers, J. Major Industrial Hazards. Their Appraisal and Control; Halstead Press: New York, 1988. (c) Readings in Risk. Resources for the Future; Glickman, T. S., Gough, M., Eds.; Washington, 1990. (d) Carson, P. A.; Mumford, C. J. The Safe Handling of Chemicals in Industry; Longman Scientific and Technical: New York, 1988; Volumes 1 and 2. (e) Sanders, R. E. Management of Change in Chemical Plants. Learning from Case Histories; Butterworth-Heinemann: Oxford, 1993. (f ) Kletz, T. Lessons from Disaster. How Organizations have No Memory and Accidents Recur; Gulf Publishing: Houston, 1993. (g) Cutter, S. L. Living with Risk. The Geography of Technological Hazards; Edward Arnold: London, 1993. (a) Petroski, H. To Engineer is Human. The Role of Failure in Successful Design; St. Martin’s Press: New York, 1982. (b) Petroski, H. Design Paradigms. Case Histories of Error and Judgment in Engineering; Cambridge University Press: Cambridge, 1994. Semiat, R.; Grinbaum, B. J. Chem. Educ. 1998, 75, 583–586. Geankoplis, C. J. Transport Processes and Unit Operations, 2nd ed.; Allyn and Bacon: Boston, 1978. Bean, J. C. Engaging Ideas: the Professor’s Guide to Integrating Writing, Critical Thinking, and Active Learning in the Classroom; Jossey-Bass: San Francisco, 1996; pp 15–36. Bressette, A. R.; Breton, G. W. J. Chem. Educ. 2001, 78, 1626– 1627. Dybowski, C. J. Chem. Educ. 2001, 78, 1623–1625. Kovac, J.; Sherwood, D. W. J. Chem. Educ. 1999, 76, 1399– 1403.
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