Nuclear fuel cycles

Fuel and Heavy Water Hvailahility, Report of Working Group 1, International Nuclear Fuel Cycle Evaluation, Vieima, Austria, International Atomic Energy Agency STl/PUB/534, UNIPUB, Inc., New York, 1980, pp. 174-175. 

Fig. 6. The nuclear fuel cycle. HLW = high level waste.

The safety principles and criteria used ia the design and constmction of the faciUties which implement the nuclear fuel cycle are analogous to those which govern the nuclear power plant. The principles of multiple barriers and defense-ia-depth are appHed with rigorous self-checking and regulatory overview (17,34). However, the operational and regulatory experience is more limited. 

The sum total of risks of the nuclear fuel cycle, most of which are associated with conventional industrial safety, are greater than those associated with nuclear power plant operation (30,35—39). However, only 1% of the radiological risk is associated with the nuclear fuel cycle so that nuclear power plant operations are the dominant risk (40). Pubhc perception, however, is that the disposition of nuclear waste poses the dominant risk. 

R. G. Wymer and B. L. Vondra, Right-Water Reactor Nuclear Fuel Cycle, CRC Press, Boca Raton, Fla., 1981. 

The main technological uses for UO2 are found in the nuclear fuel cycle as the principal component for light and heavy water reactor fuels. Uranium dioxide is also a starting material for the synthesis of UF [10049-14-6] 6 (both critical for the production of pure uranium metal and... 

Nitrides. Uranium nitrides are weU known and are used in the nuclear fuel cycle. There are three nitrides of exact stoichiometry, uranium nitride [2565843-9], UN U2N3 [12033-85-1/ and U4N2 [12266-20-5]. In addition to these, nonstoichiometric complexes, U2N3, where the N/U ratio ranges... 

Fluorides. Uranium fluorides play an important role in the nuclear fuel cycle as well as in the production of uranium metal. The dark purple UF [13775-06-9] has been prepared by two different methods neither of which neither have been improved. The first involves a direct reaction of UF [10049-14-6] and uranium metal under elevated temperatures, while the second consists of the reduction of UF [10049-14-6] by UH [13598-56-6]. The local coordination environment of uranium in the trifluoride is pentacapped trigonal prismatic with an 11-coordinate uranium atom. The trifluoride is... 

In addition to these are studies prepared before President Carter stopped the GESMO (Generic Environmental Statement for Mixed Oxide) that addressed the chemical processing of fissionable material for the nuclear fuel cycle. Some references are Cohen (1975), Schneider (1982), Erdmann (1979), Fuliwood (1980), and Fullwood (1983). 

Chun, M. K. et. al., 1989, User s Manual for FTRIN - A Computer Code to Estimate Accidental Fire and Radioactive Airborne Releases in Nuclear Fuel Cycle Facilities, NUREG/CR 30 (PNL-4S 32). PNL, February. 

Schneider, K. J., Coordinator, 1982, Nuclear Fuel Cycle Risk Assessment, Vol 1 and 2, PNL-4306. 

The Safety of the Nuclear Fuel Cycle, Organization for Eeonomic Cooperation and Development, 1993, p. 206. 

Chemical Process, Power. Petrochemical, Telecommunications, Nuclear Fuel Cycle... 

Reliability for Phase 1 of the Probabilistic Risk An ysis DPST-37-642 Nuclear Fuel Cycle upper bounds exchangers, relays, tans for systems. ... 

Nuclear Fuel Cycle R D Group, Korea Atomic Energy Research Institute P.O. Box 105, Yuseong, Daejeon, 305-600, Korea (e-mail nhcyang kaeri.re.kr)... 

Kocher, D. C. (1977). Nuclear Decay Data for Radionuclides Occurring in Routine Releases from Nuclear Fuel Cycle Facilities, Report No. ORNL/NUREG/TM-102 (National Technical Information Service, Spring-field, Virginia). 

Nuclear fuel cycle, 77 545-547 safety principles and, 17 546-547 Nuclear fuel reprocessing, 10 789-790 Nuclear fuel reserves, 17 518-530 alternative sources of, 17 527 economic aspects of, 17 526-527 toxicology of uranium, 17 528-529 uranium mineral resources, 17 518-521, 522-525... 

The second part deals with applications of solvent extraction in industry, and begins with a general chapter (Chapter 7) that involves both equipment, flowsheet development, economic factors, and environmental aspects. Chapter 8 is concerned with fundamental engineering concepts for multistage extraction. Chapter 9 describes contactor design. It is followed by the industrial extraction of organic and biochemical compounds for purification and pharmaceutical uses (Chapter 10), recovery of metals for industrial production (Chapter 11), applications in the nuclear fuel cycle (Chapter 12), and recycling or waste treatment (Chapter 14). Analytical applications are briefly summarized in Chapter 13. The last chapters, Chapters 15 and 16, describe some newer developments in which the principle of solvent extraction has or may come into use, and theoretical developments. 

Fuel. The nuclear fuel cycle starts with mining of the uranium ore, chemical leaching to extract the uranium, and solvent extraction with tributyl phosphate to produce eventually pure uranium oxide. If enriched uranium is required, the uranium is converted to the gaseous uranitim hexafluoride for enrichment by gaseous diffusion or gas centrifuge techniques, after which it is reconverted to uranium oxide. Since the CANDU system uses natural uranium, I will say no more about uranium enrichment although, as I m sure you appreciate, it is a major chemical industry in its own right. 

Meanwhile AECL and other Canadian departnents and agencies are participating actively in the International Nuclear Fuel Cycle Evaluation (INFCE) to study all fuel cycle options. No decisions on expansion of the present research level on thorium fuels will be taken until information from INFCE has been evaluated by the Canadian Government. 

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