Fuel Cycle Aspects

As with all other nuclear supplies, fuel is also subject to the non-proliferation constraints laid down in intergovernmental agreements. 

A bilateral agreement will have to exist with the government of each supplier, i.e. of uranium, enrichment services (when needed), fuel fabrication and heavy water supplies. The conditions in bilateral agreements are expressions of national policies and these have been known to be subject to change, which, for example, caused some uncertainties in 

Both these factors, the (in practice) limited number of fuel fabricators and changing national policies, have led some countries to make national self-sufficiency in fuel supply a high priority, calling for the early establishment of uranium prospecting and mining and fuel fabrication. It can also lead to the choice of a power plant type which can be fuelled with natural uranium (HWR or MAGNOX). Fuel fabrication is a fairly easy technology, but its introduction locally for an SMPR is hardly justifiable from an economic point of view. 

It is a paradox associated with nuclear power that domestic uranium resources do not constitute an energy resource for the country without a major investment in nuclear power plants and their associated technology. The feasibility of introducing nuclear power is unrelated to domestic uranium availability and is based on entirely different factors. 

More detailed information on the fuel supply situation can be found for example, the IAEA Bulletin, Vol. 26, No. 3, September 1984 and 

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To illustrate the consequences of any of these policies a few representative examples were selected, and all capital investments, operating costs, fissile material requirements, and other fuel cycle aspects are calculated using the reactor model described in Section IV. The most important characteristics of the selected examples are given in Table III. It should be borne in mind that none of these examples represents a very likely development, but that all are extreme representatives of the three different philosophies described above. These examples are only meant to illustrate... 

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. 

The coordination chemistries of the elements considered in this chapter have already been the subject of detailed discussion in earlier sections of these volumes. Consequently, it is the purpose of this chapter to review, in general terms, the nuclear fuel cycle, the production of metal radionuclides and subsequently their incorporation into radiopharmaceutical formulations. Within this framework, specific aspects of coordination chemistry which are relevant to the application in question will be considered. 

Ionova, G., Ionov, S., Rabbe, C., Hill, C., Madic, C., Guillaumont, R., Modolo, G., Krupa, J.C. 2000. The problem of Am(III)/Eu(ni) separation in the frame of hardness of cations and softness of cations and softness of extractants Theoretical aspects. ATALANTE 2000 Scientific Research on the Back-end of the Fuel Cycle for the 21st Century, October, Avignon, France. 

Akiba, K. and Nakamura, S., Transport of metal species through supported Uquid membrane containing dihexyl-A,A-diethylcarbamoyl methylenephosphonate. in Chemical Aspects of Down Stream for Thorium Fuel Cycle, Suzuki, S., Mitsugashira, T., Hara, M., Satoh, I., and Shiokawa, Y., Eds., Atomic Energy Society of Japan. Tokyo (Japan), 1987, pp. 85-90. 

Actinide separation techniques and methods play a very important role in analysis and production of nuclear materials, reprocessing of nuclear fuels, nuclear waste management, and other aspects of the nuclear fuel cycle. Professionals from several disciplines—analytical chemists, chemical engineers, process chemists, etc.—make much use of this technology. 

Wymer, R.G. Vondra, B.L. Chemical aspects of LWR fuel reprocessing. In Light Water Reactor Nuclear Fuel Cycle CRC Press, Inc. Boca Raton, FL, 1981 77-78. 

Guidelines to Ensure Health and Safety of Workers and General Public. Operations of an oil shale industry will introduce a new set of industrial working conditions and possible public health risks as a result of plant operations or product distribution. The research directed toward this need will examine the potential health and safety risks to workers and the general public. All aspects of the fuel cycle will be examined from the mine and retort to the refinery and end use of the shale oil products. Protective measures, whether they be through controls, process modifications, or isolation of high risk areas, will be evaluated and effective measures will be applied. 

Since that time the objects of the industry have changed from military to civil applications and three generations of plant have been constructed and operated. The United Kingdom reasonably can claim to have technical and industrial competence in all of the aspects of the nuclear fuel cycle, although the experience of the final disposition of highly radioactive waste is limited and affected necessarily more by social and political factors than by technology. 

The main objection against nuclear power is the risk of spread of "radioactivity" (radioactive elements) to the environment where it may cause health effects in humans. We have already discussed such effects (Ch. 18). Here, we are concerned with the chemical aspects of the sources of releases and of the migration of the radionuclides in the environment. Their chemical properties, together with hydrology, determine how fast they will move from their point of entry into the groundwater to water resources used by man this is schematically illustrated in Figure 22.1. In particular we discuss actinide behavior as these elements have the most hazardous radionuclides which may be released in the different steps of the nuclear fuel cycle, and, especially, from nuclear waste repositories. 

As part of the Ceaujescu s vision of self-reliance, Romania also developed perhaps the most technologically demanding aspect of a CANDU-6 fuel cycle the production of heavy water for reactor moderation and cooling. This activity is undertaken by the Romag-Prod facility in the south-west of the country. The Romag-Prod facility is a key part of the Regia Autonoma Pentru Activitati Nucleare (RAAN) (Romanian Authority for Nuclear Activities) of the Ministry of Economy and Finance. ... 

The ultimate program purpose is the assurance of safe operation at Russian nuclear materials industrial enterprises and sites associated with the treatment, storage, and disposition of excess HEU and Pu derived from various origins, including dismantled nuclear weapons. Efforts to benchmark safety management at select Russian defense fuel cycle facilities will be incorporated into all aspects of the... 

Scientific and technical aspects of the nuclear fuel cycles based upon MOX-fuel utilization ... 

AR251 Trends in the nuclear fuel cycle Economic, environmental and social aspects. Nuclear... 

This study aims at a comparison of future reactor concepts, paying particular attention to aspects of safety, of the fuel cycle, the economics, the experience-base and the state of development. Representative examples of typical development lines, that could possibly be of interesf within a time horizon of 50 years were selected for comparison. This can be divided into three phases ... 

The choice of the moderator material for a central-station powerplant is generally based on the economics involved. Obviously, many factors other than the cost per unit weight or volume, per se, enter into the economics. The neutron slowing-down capability of the material has an important effect on the size of the reactor core and, therefore, the capital cost of the plant, because of the investment in moderator, pressure vessel, shielding, etc. Containment requirements for the moderator (particularly liquid moderators) can affect both the capital cost of the plant and the fuel cycle economics, the latter because of possible neutron losses. Integrity and stability of the moderator material can, of course, have important implications on other aspects of the reactor design. The neutron absorption behavior of the moderator itself affects the potential conversion ratio of the reactor and, therefore, the fuel cycle economics of the reactor. The properties of the more important moderators and the implications of these properties on the choice and performance characteristics of gas-cooled reactors will be reviewed in this section. 

Moreover, there is a potential application of polymeric membranes for integrated gasification combined cycle (IGCC) power plants, some aspects of the integration of a membrane reactor with a fuel cell, the possibility to integrate a membrane reformer into a solar system, and the potential application of membrane integrated systems in the fusion reactor fuel cycle, which are attracting many scientists and so will also be introduced and discussed in this chapter. 

The intent of this review is to indicate how the methods of probabilistic safety can be applied to the analysis of potential accidents in the miclear fuel cycle, excluding reactors. There has been considerable effort spent in analyzing selected aspects of the fuel cycle from a probability viewpoint, but there has been little work done to analyze the complete cycle with die intent of either balancing the risks from the various components or quantifying the total risk. 

Thwgh relatively few students will eventually be employed iii the criticality safety field, those exposed to this program will have the valuable experience of seeing nearly all of the engineering and administrative aspects of one important part of the nuclear fuel cycle. This is sure. to. provide useful insight into any other area of nuclear, engineering in which they may choose to work. 

This section discusses several aspects of the nuclear fuel cycle and the life cycle of nuclear systems. It begins with a discussion of uranium, which is the basic fuel of the current generation of nuclear systems, and is presented in Chapter 10. Uranium-containing minerals are mined and purified so that they can be further processed. Uranium as found in nature is primarily made up of the U-238 isotope, and it contains about 0.7% U-235, which is the isotope that is the primary fuel in today s reactors. The fissioning of 1 g of uranium will yield 1 MW day of energy or 24,000 kW h. 

In Chapter 2, we take a more detailed look at the analytical chemistry pertaining to key commercial activities, that is, uranium mining and its utilization in the nuclear fuel cycle (NFC) first, in the milling process, uranium-containing deposits are processed to form uranium ore concentrates (UOC) that are then shipped to uranium conversion facilities (UCF), where the uranium is transformed into high-purity nuclear grade compounds. These can serve as fuel for nuclear power plants or as feed material for isotope enrichment. Then we discuss the analytical aspects of compliance with the strict specifications of the materials used in enrichment plants and in fuel fabrication facilities. Finally, we deal with the analytical procedures to characterize irradiated fuel and waste disposal of spent fuel. 

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