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[en] The paper reviews the technical status of plutonium recycle in thermal reactors in the Foratom countries and assesses the prospect for it becoming established in the future with the implicit assumptions that uranium oxide reprocessing capacity will be installed commensurate with the projected programmes for thermal reactor installation and that there will be no insuperable environmental, security or safeguards obstacles to the use of plutonium as a fuel. It is argued that the feasibility of using plutonium as an alternative to 235U as the fuel for thermal reactors, particularly LWRs, has been extensively demonstrated by a number of Foratom countries and the main problem areas are fuel fabrication and fuel reprocessing. Mixed-oxide fuel fabrication has been well established on the prototype plant scale using low-irradiation plutonium, but it is recognized that the future design of production-scale plants will need to cater for the significantly higher radiation levels from high burnup plutonium and meet stricter environmental requirements on operator dosage and waste arisings. The main constraint on the establishment of recycle up to now has been the lack of available plutonium owing to the absence of significant uranium-oxide fuel reprocessing capacity. An assessment of the plutonium arisings in Europe, based on the projected uranium-oxide reprocessing capacity, shows that by 1990 plutonium, surplus to FBR requirements, should be accumulating by about 10t/a, sufficient to fuel about 8000MW(e) of LWRs. A further constraint would then be the availability and technical problems of mixed-oxide reprocessing, which is one of the areas identified for international collaboration. It is concluded that whilst there is unlikely to be substantial recycle of plutonium in thermal reactors in the Foratom countries before the early 1990s, an incentive could possibly arise about that time. The strength of this incentive will depend on a number of factors including the status of the fast breeder reactor, the cost and availability of uranium ore and the desirability of recycling plutonium from security considerations. (author)
[en] The investigation of the thorium fuel cycle (ThFC) is a collaborative INPRO (International Project on Innovative Nuclear Reactors and Fuel Cycles) activity within its main area on global vision on sustainable nuclear energy for the 21st century. The current publication reports on the sustainability of nuclear power by re-examining the potential of thorium-based fuel cycles to support future large scale deployment of nuclear energy systems by increasing the availability of nuclear material. Special attention is paid to the thorium fuel cycle from the point of view of economics and proliferation resistance.
[en] Taking as their starting point the various power reactor construction programmes, the authors estimate in the first part of the paper the production of plutonium in the non-socialist world for the period up to 1980. They also estimate the plutonium requirements of the various fast reactor programmes. For the period up to 1970-71, it is found that United States requirements will be satisfied only by drawing on the United States Atomic Energy Commission's stocks and through the exchange agreement with the United Kingdom. For the rest of the world, resources and requirements will be more or less in equilibrium. From 1971 onwards production will greatly exceed the requirements of fast reactors, which will still only be at the prototype stage. If it is assumed that the large-scale construction of fast reactors will not begin until ten years later, the only outlet for plutonium, for which there will no longer be a guarantee of repurchase by the USAEC in the case of enriched uranium reactors, will consist of recycling in thermal reactors. Storage with a view to re-use in breeders at a more remote and indeterminate date would impose an intolerable financial burden on power reactor operators. The question thus arises whether a collapse in the price of plutonium will occur after 1970. In the second part of the paper the authors attempt to predict the course of such a price collapse, followed by a rise as breeders enter service on a commercial basis. They discuss the effects that the absence of plutonium stocks and die competition of recycling in thermal reactors might have on the commercial introduction of breeders. Finally, an attempt is made to determine by what mechanisms a harmonious market for plutonium could be assured during the next fifteen years. (author)
[fr]Dans une première partie on procède - î partir des programmes de construction de centrales nucléaires - à une estimation de la production de plutonium dans le monde non socialiste jusqu'en 1980. On estime par ailleurs les besoins de plutonium des divers programmes de réacteurs de la filière rapide. On constate que dans une première période allant jusqu'en 1970 ou 1971 les besoins américains ne seront satisfaits que grâce aux stocks de la Commission de l'énergie atomique et au contrat de troc avec le Royaume-Uni. Pour le reste du monde, ressources et besoins sont à peu près équilibrés. A partir de 1971, la production dépassera très largement les besoins des réacteurs rapides, qui ne seront encore qu'à l'état de prototypes. Si l'on admet que leur construction en série ne commencera que 10 ans plus tard, le plutonium, qui pour les réacteurs a uranium enrichi ne bénéficiera plus de la garantie de rachat de la CEA des Etats-Unis, n'aura d'autre débouché que le recyclage dans les réacteurs thermiques. Le stockage en vue d'une réutilisation dans les surgénérateurs à une date lointaine et indéterminée constituerait en effet pour les exploitants de centrales une charge financière intolérable. Assistera-t-on à partir de 1970 à un effondrement du prix du plutonium? Dans la deuxième partie, on essaie de prévoir comment s'opérerait un tel effondrement, puis la remontée du prix lors du démarrage industriel des surgénérateurs et quelles conséquences pourraient avoir sur ce démarrage l'absence de stock de plutonium et la concurrence du recyclage dans les réacteurs thermiques. En conclusion, on essaie de définir les mécanismes qui pourraient permettre un fonctionnement harmonieux du marché du plutonium dans les 15 prochaines années. (author)
[en] Beginning in 1973, the USAEC started the analysis of the benefit/cost balance of Pu recycling in light-water reactors and the US Nuclear Regulatory Commission has continued this effort to the present time. A study of the United States nuclear industry from 1975 until 2000 was summarized in a final environmental statement called GESMO - Generic Environmental Statement on Mixed Oxide, NUREG-0002. Cumulative environmental and economic effects for several industry growth patterns were determined. Five alternatives were evaluated, covering the basic options of recycling uranium and plutonium; recycling uranium; and no recycling. The NRC findings, excluding consideration of proliferation and safeguards questions, are: the safety of reactors and fuel-cycle facilities are not significantly affected by recycle; excluding consideration of radiological effects, the environmental effects of recycle are slightly less than those from a non-recycle system; plutonium recycling extends uranium resources and reduces environmental impacts at the same time requiring reprocessing and Pu-handling facilities; despite uncertainties, recycling has probable economic advantages over other fuel concepts; differences in health effects attributable to recycling provide no basis for selecting a particular fuel-cycle option; no waste-management considerations appear that could be a basis for the selection of any particular option. The NRC studies on health, safety and environmental considerations of Pu recycling in the United States of America show that the differences in benefits/costs between the alternative fuel cycles are small and hence do not provide a clear basis for a decision on Pu recycle at this time. Safeguards and international proliferation implications appear to be the controlling factors in reaching a decision. President Carter's statement indefinitely deferring reprocessing and Pu recycle in the United States of America has resulted in a re-evaluation by NRC of its programme to reach a decision on whether or not to authorize Pu recycling. (author)
[en] A brief review is presented of the plutonium supply and demand position in the early 1970s. The possible range of requirements for thermal burning is considered in relation to the available supply of plutonium and in comparison with the alternative of storage for fast reactor fuelling. The scope for international trading is noted. Consideration is then given to the alternative processing, storage and fabrication routes which are likely to be available, taking account of the international trading involved. The facilities which will have to be created for the various processing, storage and fabrication operations are described, and the investment in plant and in plutonium hold-up is evaluated. Finally, consideration is given to the different ways in which the various aspects of plutonium trading can be handled, taking account of the serious financing problems involved. (author)
[en] It is clear that in the next decades there will be a substantial and increasing demand for uranium to fuel nuclear power stations. In a developing country, the discovery and development of uranium resources can be of importance either for the development of national nuclear power or for the commercial export of uranium. As the time taken between the start of a uranium exploration program and the uranium production stage.may be of the order of 6 - 10 years, it is now opportune to start new exploration so that advantage of the increased demand in the mid-1970s may be achieved. Thorium will also be of interest, but in the more distant future when the thorium cycle for advanced converters and breeder reactors is fully developed
[fr]Il est certain qu' au cours des prochaines décennies la demande d'uranium pour les centrales nucléaires sera importante et ne cessera de croître. Dans un pays en voie de développement, la découverte et la mise en valeur de ressources d'uranium peut avoir une grande importance, soit en vue de produire de l'énergie nucléoélectrique, soit en vue d'exporter l'uranium. Etant donné que les délais entre le démarrage d'un programme de prospection de l'uranium et le début de la production peuvent être de l'ordre de six ans, il est actuellement opportun de commencer les opérations d'exploration pour pouvoir profiter de la demande accrue qui s' affirmera vers le milieu de la prochaine décennie. Le thorium présentera aussi un certain intérêt, mais à plus long terme. Il faut pour cela que le cycle du thorium pour convertisseurs avancés et surgénérateurs ait été pleinement développé. (author)
[en] The approach applied in the study is based on the internationally verified framework developed in the INPRO collaborative project “Global Architecture of Innovative Nuclear Energy Systems with Thermal and Fast Reactors and a Closed Fuel Cycle” (GAINS) GAINS project [XIV-1] includes 8 framework cases for Homogeneous and Heterogeneous (multi-group) world for high and moderate demand scenarios based on once-through and closed fuel cycle. The INPRO collaborative project SYNERGIES - Synergistic Nuclear Energy Regional Group Interactions Evaluated for Sustainability applies and amends the analytical framework developed in GAINS to model more specifically the various forms of collaboration among countries, assess benefits and issues relevant for collaboration and identify those collaborative scenarios and architectures that ensure a ‘win-win’ strategy to both, the suppliers and users. The GAINS framework classifies non-personified countries into three country groups according to their nuclear fuel cycle strategies: NG1 countries pursue fast reactor programme and perform recycling of SNF; NG2 countries either directly dispose of the SNF or send it to NG1 for reprocessing; and NG3 countries are LWR based newcomer countries that send the SNF back to NG1 or NG2. The analysis methodology in this study is based on varying the allocation of future nuclear energy generation share of each country group as function of time for assessment of different scenarios, in comparison to the GAINS studies where the NG1:NG2:NG3 ratio was kept fixed at 40:40:20. The sensitivity analysis is targetted on studying the behavior of global nuclear energy system shares in terms of its key parameters and stress limits under variations in country group. The GIANS studies were performed under fixed NG1:NG2:NG3 share ratio held at 40:40:20. This study explores possibility of transition of NG1 and NG2 groups under changes in NG1:NG2 proportion. The study also assesses impact of NG3 share variation on NG1/NG2 front end and back end fuel cycle requirements.The present study assumes high demand scenario established by the GAINS for nuclear power generation demand growth based on long term energy demand scenarios developed by the IAEA and IPCC. According to the adopted high demand scenario, the energy demand grows to 5000 GW(e).year in 2100 and flattens afterwards. The base case BAU-FR is considered with three reactor types namely LWR, HWR and FR (BR=1.0). Brief description of reactor characteristics used in the study is provided. The fast reactors are assumed to replace LWRs gradually upon introduction. The share of HWRs in nuclear energy mix is assumed to be constant at 6% and independent of FR introduction.
[en] This annex compiles the results of relevant French and Russian scenarios for closing the Plutonium cycle with the introduction of a number of fast reactors. The studies presented in this annex fall into SYNERGIES Task 1 on Evaluation of synergistic collaborative scenarios of fuel cycle infrastructure development. The objectives of the studies compiled in this annex are to address the problem of SNF accumulation from LWRs and to decrease natural uranium consumption based on possible closed fuel cycle scenarios involving the introduction of a number of fast reactors under development in France and Russia.
[en] Various factors have caused changes in the characteristics of nuclear fuel cycles from what was envisioned in many nations in the early days of commercial nuclear power development. Most notably, commercial deployment of fast breeder reactors has been substantially delayed, leading to a commercial demand for plutonium that is lower than once projected. Reprocessing of spent fuel to recover plutonium has progressed in some countries according to plans which were based on more extensive development of nuclear power in general and a foreseen need for plutonium fuelled breeders to ensure an adequate nuclear fuel supply. Plutonium recycling in thermal reactors is now being adopted in several countries. This analysis reviews the factors which have had the greatest influence on nuclear fuel cycle characteristics in the nations of the world outside centrally planned economies area (WOCA), and describes the resulting strategies of ten individual nations with respect to spent fuel management, plutonium and uranium recycling, and waste disposal. Country specific data are provided on spent fuel generation, reprocessing capacities, breeder development, mixed oxide fuel fabrication, and waste disposal plans and schedules. The analysis shows that the factors identified have not had a uniform impact on the nations surveyed, as some now plan once-through use of fuel while others are reprocessing and continuing efforts to demonstrate breeder technology. This situation highlights the need for nations with different fuel cycle strategies to coexist and accept the approaches in other nations as the most appropriate strategies for the individual energy needs of those nations. Such coexistence is essential for maintenance of positive international relations in nuclear energy and achievement of common non-proliferation objectives. (author). 12 refs, 1 fig., 5 tabs