AC : A PROJECT-BASED APPROACH TO TEACHING THE NUCLEAR FUEL CYCLE

Transcription

1 AC : A PROJECT-BASED APPROACH TO TEACHING THE NUCLEAR FUEL CYCLE Erich Schneider, Dr. Schneider received his PhD in Theoretical and Applied Mechanics from Cornell University in During the final two years of his graduate study at Cornell, he held the position of Lecturer. From , he was a Technical Staff Member in the Nuclear Systems Design Group at Los Alamos National Laboratory. In January, 2006, Dr. Schneider joined the Mechanical Engineering faculty at the University of Texas at Austin. He is affiliated with the Nuclear and Radiation Engineering Graduate Program at that institution. American Society for Engineering Education, 2007 Page

2 Abstract A Project-Based Approach to Teaching the Nuclear Fuel Cycle The nuclear fuel cycle defined as the series of processes through which materials pass in the course of electricity generation is accepted as a subject in which graduating nuclear engineering students should be well-versed. While a technology-based, water reactor-based approach to teaching the fuel cycle has a great deal of validity, it can be argued that other approaches can offer students superior preparation to participate in today s national (e.g. the Advanced Fuel Cycle Initiative and Global Nuclear Energy Partnership) and international debate regarding the future direction of the fuel cycle. The concepts generated by these and other research programs are evolving rapidly, as are the tools used to assess them. Hence, no single text can function as a comprehensive resource for a course that seeks to provide an up-to-date treatment of the fuel cycle. A new course taught in Fall, 2006 at The University of Texas, Austin takes the systems analyst s perspective as opposed to that of the traditional technologist. This perspective emphasizes understanding how each element of the fuel cycle contributes to the functionality of the system as a whole. The course is unique in that it draws readings, examples and case studies entirely from the contemporary literature. It also features a semester project a fuel cycle system analysis that requires on-campus and distance learning students to collaborate. Introduction This is a watershed era in the enterprise of nuclear energy production. A great number of advanced reactor technologies and fuel cycles are being proposed and debated. When considering fuel cycles, policymakers require input that is not solely technical in nature, but rather folds technical factors, along with those that are economic and geopolitical in nature, into a balanced, comprehensive picture of how a fuel cycle would impact the international energy production milieu. The intention of this paper is to present an approach to teaching the fuel cycle that prepares graduate students to engage in cross-cutting, systems-level analysis of this nature. While fuel cycle systems analysis courses are offered at some institutions, this author found that no up-to-date text one that draws upon very recent work by the Advanced Fuel Cycle Initiative, Global Nuclear Energy Partnership, Organization for Economic Cooperation and Development (OECD) Nuclear Energy Agency and others is available. Therefore, a curriculum that draws upon recent works by these programs and agencies, using their publications in lieu of a textbook, was prepared. An extensive bibliography of these papers and reports is presented. Objectives and Approach Page

3 The course objective was conveyed to the students via the following text, which appeared on one of the first slides presented: Many buzzwords circulate in the literature and the media. The buzzwords serve a purpose, but by themselves they obfuscate the science. Go to and you will find this menu of features that the Global Nuclear Energy Partnership (GNEP) promises to fulfill: Proliferation-Resistant Recycling Minimize Nuclear Waste Advanced Burner Reactors Reliable Fuel Services Small-Scale Reactors Nuclear Safeguards The objectives of the class are: to convey the science behind buzzwords like these, to give students the tools needed to understand, analyze and compare fuel cycles. To explain the structure of the course to the students, Figure 1 was used. The figure shows a cartoon of the components of the fuel cycle at top; crosscutting elements that must be considered in systems analysis are shown. The figure is intended to emphasize that a basic grasp of the individual technologies, in the context of how they affect the cross-cutting factors, is one fundamental aim of the class. The second fundamental aim is to equip students with the analytical tools they need to assess the cross-cutting factors in a manner that is technically sound as well as communicable to nonspecialists. Economics Proliferation Resistance/ Safeguards Repository Impact Resource Sustainability Figure 1. The Nuclear Fuel Cycle: Components (top) and Crosscuts The course schedule is presented in Table 1. Crosscuts and case studies occupy twothirds of the instruction time, with a contextual review of the component technologies comprising the remainder. Homework assignments were completed by students on an individual basis; they consisted of a conventional problem-solving component plus a literature review element. The literature review involved information-gathering on Page

4 subjects relevant to that week s topic: for instance, when uranium supply being covered, each student was assigned a uranium mine (drawn from the top twelve by total reserves). The assignment consisted of researching the history of the facility, the nature, ore grade and geologic morphology of the uranium deposit, and the mining technique(s) used to recover it. It was turned in as a one page writeup or three slides. Table 1: Course Schedule Time Topic / Activity HW / Test / Project Week 1: Introduction; Fuel Cycle Overview 8/31/06 Week 2: 9/5, 9/7 History, Hot Topics: the AFCI, GNEP, Transmutation Week 3: 9/12, 9/14 The Front End: Uranium Mining and Supply, Conversion Week 4: 9/19, 9/21 The Front End: Enrichment, Fuel Fabrication 9/19: Written Proposal Due Week 5: The Reactor as a Component of the Fuel Cycle: 9/26: HW 1 Due 9/26, 9/28 Types, Objectives Week 6: 10/3, 10/5 The Reactor: Fuel Burnup, Linear Reactivity Model Week 7: 10/10, 10/12 The Back End: Open Fuel Cycle Group Presentations 10/10: HW 2 Due 10/12: Presentations Week 8: 10/17, 10/19 The Back End: Closed Fuel Cycle: Reprocessing, Disposal 10/17: Org Chart Due Week 9: Crosscuts: Economics 10/24: HW 3 Due 10/24, 10/26 Discounting, Cost Benefit Analysis Week 10: 10/31, 11/2 Crosscuts: Economics Fuel Cycle Economics, Externalities Week 11: Crosscuts: Repositories and Disposal 11/7: HW 4 Due 11/7, 11/9 Yucca Mountain and Transmutation Case Study Week 12: 11/14, 11/16 Crosscuts: Proliferation Resistance Crosscuts: Resource Sustainability 11/16: Progress Report Due Week 13: Examination: 11/21 Includes Material Covered Through 11/2 Week 14: Prospects for Gen-IV and Beyond 11/30: HW 5 Due 11/28, 11/30 Transmutation, France and Germany: Case Study Week 15: 12/5, 12/7 Team Presentations Textbooks 1 treating the fuel cycle from a technologist s perspective are available. This author could not, however, identify a text that was both up-to-date covering the very significant developments that have taken place under programs such as the Advanced Fuel Cycle Initiative (AFCI) and GNEP and systems analysis oriented. Therefore, most reading and reference material for the class was drawn from the current literature: class readings included technical reports and journal articles. Reviewing the Page

5 contemporary literature in the field and selecting readings appropriate for use by learners proved to be the most time-consuming aspect of curriculum development for the class. Hence, the bibliography of readings presented in Table 2 may afford substantial time savings to future instructors of fuel cycle systems analysis courses. We have attempted to organize these readings into major headings; however, a number of them address more than one of the subject areas. Table 2: Partial Bibliography for Fuel Cycle Course Reactor Characterization for Systems Analysis Blue Ribbon Commission Report on Proliferation Resistant Characteristics of Light Water Reactor Fuel, Driscoll et al., The Linear Reactivity Model for Nuclear Fuel Management, OECD, Physics and Safety of Transmutation Systems, High Level Systems Analyses Schneider et al., Nuclear Fission, GNEP, Report to Congress: Spent Nuclear Fuel Recycling Program Plan, Advanced Fuel Cycle Initiative Comparison Report, 2003 and , 8 Comprehensive Systems Analyses Generation IV Roadmap: Report of the Fuel Cycle Crosscut Group, DOE Report, Accelerator Driven Systems and Fast Reactors in Advanced Nuclear Fuel Cycles, OECD Nuclear Energy Agency, NEA-3109-ADS, The Future of Nuclear Power, Massachusetts Institute of Technology Study, Resource Sustainability Schneider, Long Term Uranium Supply Estimates, MacDonald, Uranium: Sustainable Resource or Limit to Growth? Neff, Insights Into the Future: Uranium Prices and Formation , International Atomic Energy Agency, Analysis of Uranium Supply to 2050, Disposal / Storage Impact Wigeland, Criteria Derived for Geologic Disposal Concepts, Bunn et al., Interim Storage of Spent Nuclear Fuel, Bunn et al., The Economics of Reprocessing vs. Direct Disposal of Spent Nuclear Fuel, DOE, Total System Life Cycle Cost of Civilian Radioactive Waste Management, Economics Bunn et al., The Economics of Reprocessing vs. Direct Disposal of Spent Nuclear Fuel, Smith et al., Estimated Cost of an ATW System, The Economics of the Nuclear Fuel Cycle, OECD Report, Proliferation Resistance Bragin et al., Integrated Safeguards: Status and Trends, Charlton et al., Proliferation Resistance Assessment Methodology for Nuclear Fuel Cycles, Yim, Nuclear Non-Proliferation and the Future Expansion of Nuclear Power, Page

6 Exams and homeworks were de-emphasized in favor of student group projects. The following section is excerpted / paraphrased from the document prepared to convey the project objectives to the students. The Project Assignment: Excerpt Whether we as engineers like it or not, the choice of a nuclear fuel cycle is a matter of national and international policy. Witness Iran, North Korea, India and Pakistan as well as the debates in this country over Yucca Mountain and nuclear fuel reprocessing. As engineers, we must of course understand the technologies that comprise the nuclear fuel cycle. But we are also called upon to explain to policymakers how the system produced by this combination of technologies will function. what will it cost? Would it be competitive and practical? what is its impact on national and global proliferation concerns? what is the strategy for handling spent fuel or other waste forms? what are the downsides? What R&D is needed to get from here to there? As specialists in fuel cycle systems engineering, you have proposed that your country consider a new fuel cycle policy. Your government has responded with a request that you conduct a systems study outlining the mechanics of your proposed fuel cycle: what are the mass flows of nuclear material? What infrastructure (government or privately financed and owned) would be required to implement it? the technologies that would need to be developed. For example, if reprocessing is necessary, would aqueous or dry processes be used? Flowsheets and other plant specifications must be given. Process efficiencies need to be calculated. metrics defined and computed: why would this fuel cycle be a good choice as compared to a continuation of current practice? Cost, resource sustainability, security of supply, feasibility, public acceptance, proliferation and waste disposal concerns could all factor in. This project is motivated by the national and international dialogue concerning the future of nuclear power that has of late occupied utilities and policymakers and spilled over into the popular media. The question of which fuel cycle to adopt is intimately tied to this issue. There s a strong feeling in some quarters that the once through fuel cycle currently practiced in most countries is not sustainable for the indefinite future. We are casting about for options. There are plenty of examples of systems studies comparing the options to be found in the technical literature. Page

7 You ll notice that many of these studies run to hundreds of pages and include detailed calculations made using sophisticated computer codes. I m not expecting that level of depth or comprehensiveness. You definitely need to cover: background: present-day nuclear fuel cycle (the basis for comparison) objectives your fuel cycle strategy is intended to meet, specified clearly and (where possible) quantitatively the mechanics of your scheme: reactor and fuel cycle material balances advanced or other not-yet-deployed technologies (reactors, fuel cycle facilities, fuel forms, separations processes with flowsheets, etc.) that would need to be developed under your scheme: prospects, capacity or number of facilities comparative analysis of crosscuts: economics, intrinsic and extrinsic proliferation resistance, resource needs, etc. Finally and most importantly, you must draw conclusions: to what extent does the fuel cycle meet the goals you defined? What are the obstacles standing in the way of its deployment? Even this is a lot of content. I don t expect you to thoroughly cover every point. One of your early tasks will be to choose areas on which to focus (or perhaps you ve found some existing research and are filling in the blanks). I ll advise you early on if I think you re omitting anything crucial. Project Administration At the beginning of the semester, the students were given a questionnaire that solicited their level of interest in various aspects of a fuel cycle systems analysis. A portion of the questionnaire is reproduced in Table 3. Table 3. Questionnaire for Group Project: Areas of Student Interest Rate, on a scale of 1=most interested to 4=not very interested, Topic Reactor Modeling and Physics Economics and Cost Benefit Analysis Rating Fuel Cycle Systems (Fuel Fabrication & Reprocessing technologies etc) Nuclear Power Sustainability (Resource Supply, Nonproliferation, Waste Disposal) In Fall, 2006, there were three four-person teams. They produced projects entitled Thorium-Based Fuel Cycle Strategy for India, Arcadian Energy: A Review of Nuclear Power Options for Developing Nations, Fast Breeder Reactors for the Next Century of India s Nuclear Future. Page

8 Placing the study in the context of a real economy was required for the assignment. Two of the groups chose India for this, as its pursuit of thorium fuel cycles is both unique and relatively poorly studied. While both groups considered the Th-232 U-233 cycle, one team chose to utilize only existing or near-future technology (Canada Natural Deuterium Uranium (CANDU) reactors and Indian derivatives thereof), while the other looked at a fast reactor based U-233 breeding economy. The third group chose to address the options available to a developing country considering the nuclear energy option under the framework of the Global Nuclear Energy Partnership. In this context, the team compared three fuel cycles: the traditional Gen-III+ LWR cycle, a variant involving small modular battery reactors, and the option of hosting a small number of Integral Fast Reactor (IFR)-type modular transmuters on their soil. The strong distance learning component of the graduate program at UT-Austin placed the group projects in a unique situation. Each of the teams had at least one distance learning participant; one of the teams had two. While it was felt that this component should not have placed an undue strain on the groups: at the national laboratory level, for instance, systems and other studies are conducted as multi-laboratory efforts, with the attendant obstacles that poses for collaboration. In practice, however, it proved difficult for the students to collaborate effectively, and time management for a project of this magnitude was also a challenge. Quoting from student comments: I'm not sure exactly how the other groups feel, but I think most of the burden (per person) of the project gets put on the on campus students. This project was very difficult for me because my group members were hard to get in touch with to coordinate the presentations and reports. On top of that, [the distance learner] often submitted [his/her] contribution (both the final presentation and paper) last minute despite requests to get it sooner. I understand it is hard to juggle a full time career and class - but we didn't get any s asking for deadline extensions or help. So, to summarize, I feel like [Distance Learner] didn't do a proportionate amount of work (ZERO calculations/analysis), and the work [he/she] did do was not the best, and it was usually submitted too late for us to fully edit it. We all did equally poorly on project planning. I did poorly allotting enough time for this project in my schedule, but several other group members didn't finish their work and sections had to be redone at the last minute and it came out poorly throughout the semester. In spite of the negative aspects of the collaborative experience for the students, the quality of work produced was for the most part high. The students pulled together reactor analysis, time dependent fuel cycle material balance calculations, fuel cycle material characterization and crosscuts such as economics and repository impact to produce solid systems studies. One of the projects was presented to the GNEP Systems Analysis Page

9 Working Group at INL on January 8, The writeup for this project is being submitted to Progress in Nuclear Energy; portions of the other two projects are being submitted as conference papers to GLOBAL Conclusions This paper has discussed a new Nuclear Fuel Cycle course taught at UT-Austin in Fall, While fuel cycle classes have been taught at other institutions from the technologists perspective as well as (to a lesser extent) that of the systems analyst, this offering was unique in that is was taught almost entirely from the contemporary literature. The dearth of modern textbooks that teach fuel cycle systems analysis, coupled with the rapid strides in thinking within this field achieved by the AFCI, Generation-IV and GNEP programs, led us to choose this path. The documents that were utilized as teaching materials are given in this paper. We also made a full-scale, cross-cutting systems study the centerpiece of the new course. This study, which consisted of an American Nuclear Society style extended abstract, 1 hour presentation and 50 page written document, was conducted by each of three fourperson teams. The teams selected a country and fuel cycle(s) that interested them; for each candidate fuel cycle, they analyzed and compared the evolution of the nuclear enterprise in that country. The studies required the application of reactor physics and burnup calculations, cost benefit economics, quantitative proliferation resistance analysis, and other analytical methods. While project integration proved a challenge to most groups, the quality of the projects was sufficiently high to warrant presentation at national laboratories and conferences; publication of one of the final reports in a refereed journal is planned. The issues raised by on-campus students regarding difficulties coordinating their projects with the distance learning students suggest that long-distance collaboration on a project with a research flavor is difficult to pursue within the classroom milieu. That is, distance learners schedules and availability conflict with resident students in ways that cannot easily be resolved, certainly not when the collaborative effort faces deadlines driven by the academic calendar. Therefore, in the future we plan to offer a much more loosely collaborative project to the distance learning students. The distance learners will be given one of the projects submitted in an earlier year and asked to conduct their own analysis of an element of the work that they choose (e.g., cost benefit analysis, fuel burnup simulation, fuel cycle facility characterization). The interdependence between on-campus and distance students will be removed, but at the cost of isolating the distance learners to an extent. This course was intended to train students to participate in fuel cycle systems analyses as they are carried out today by GNEP, the OECD Nuclear Energy Agency and other leading government funded projects and organizations. It is our hope that the approach and reading list presented here will be of value to other instructors in preparing similar offerings. Page

10 1 Cocran, R. and N. Tsoulfanidis, The Nuclear Fuel Cycle: Analysis and Management, American Nuclear Society Press, LaGrange Park, IL, Waltar, A. and R. Omberg, eds., An Evaluation of the Proliferation Resistant Characteristics of Light Water Reactor Fuel with the Potential for Recycle in the United States, Technical Report, November Driscoll, M., Downar, T. and E. Pilat, The Linear Reactivity Model for Nuclear Fuel Management, American Nuclear Society Press, LaGrange Park, IL, OECD Nuclear Energy Agency, Physics and Safety of Transmutation Systems: A Status Report, OECD Report NEA-6090, Schneider, E. and W. Sailor, Nuclear Fission, Sci. Glob. Security, 14:183, US Department of Energy, Report to Congress: Spent Nuclear Fuel Recycling Program Plan, Technical Report, May US Department of Energy, Office of Nuclear Energy, Science and Technology, Advanced Fuel Cycle Initiative (AFCI) Comparison Report, FY 2003, DOE Report, October US Department of Energy, Office of Nuclear Energy, Science and Technology, Advanced Fuel Cycle Initiative (AFCI) Comparison Report, FY 2004, DOE Report, September Generation IV Roadmap: Report of the Fuel Cycle Crosscut Group, DOE Report, March OECD Nuclear Energy Agency, Accelerator Driven Systems and Fast Reactors in Advanced Nuclear Fuel Cycles, OECD Report NEA/3109-ADS, Massachusetts Institute of Technology, The Future of Nuclear Power: An Interdisciplinary Study, Technical Report, Schneider, E. and W. Sailor, Long Term Supply Estimates, LA-UR , Nucl. Tech., in review, C. MacDonald, Uranium: Sustainable Resource or Limit to Growth? Proc. World Nuclear Association Annual Symposium, London, September T. Neff, Insights into the Future: Uranium Prices and Price Formation , Proc. World Nuclear Association Annual Symposium, September International Atomic Energy Agency, Analysis of Uranium Supply to 2050, IAEA Report STI/PUB/1104, R. Wigeland, Criteria Derived for Geologic Disposal Concepts, Proc. 9 th OECD/NEA Information Exchange Meeting on Actinide and Fission Product Partitioning and Transmutation, Nimes, France, September M. Bunn et al., Interim Storage of Spent Nuclear Fuel: A Safe, Flexible and Cost-Effective Near-Term Approach to Spent Fuel Management, Harvard University and University of Tokyo Report, June Bunn, M., Holdren, J., Fetter, S. and B. Van Der Zwaan, The Economics of Reprocessing versus Direct Disposal of Spent Nuclear Fuel, Nuclear Technology, 150:209, June US Department of Energy, Analysis of the Total System Life Cycle Cost of the Civilian Radioactive Waste Management Program, DOE Report DOE/RW-0533, May Bunn, M., Holdren, J., Fetter, S. and B. Van Der Zwaan, The Economics of Reprocessing versus Direct Disposal of Spent Nuclear Fuel, Nuclear Technology, 150:209, June R. Smith et al., Estimated Cost of an ATW System, Pacific Northwest National Laboratory Report PNNL-13018, October OECD Nuclear Energy Agency, The Economics of the Nuclear Fuel Cycle, OECD Report, Bragin, V., Carlson, J. and R. Leslie, Integrated Safeguards: Status and Trends, The Nonproliferation Review, Summer W. Charlton et al., Proliferation Resistance Methodology for Advanced Fuel Cycles, submitted to Nucl. Tech., 2006, available: 25 M-S Yim, Nuclear Nonproliferation and the Future Expansion of Nuclear Power, Progress in Nuclear Energy 48:504, August Page