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[en] This paper presents recent results from the USAEC's Plutonium Utilization Program conducted by Battelle-Northwest. The information will be presented at the Panel on Plutonium Utilization to be held by the International Atomic Energy Agency, September 2-6, 1968. A second paper ''United States Programs on Plutonium Utilization in Thermal Reactors'' presents a review of the plans of the program being conducted and, therefore, this paper will be primarily a status report on the technology of plutonium. The large number of water reactors purchased by U.S. utilities in the past few years will be put in operation in the late 1960's and early 1970's. These reactors will produce large quantities of plutonium and a plutonium excess for the United States is predicted for around 1973. Today it appears unlikely that fast reactors will develop soon enough to use this plutonium. Storing of the plutonium until fast reactors are developed does not appear economically feasible. Since the fuel cycle cost of the water reactors reflect a plutonium credit of 0.2 to 0.4 mils/Kwh, economic utilization of plutonium must be realized in order to effect this fuel cycle cost reduction. In the United States, water reactors will probably be the only reactors available in the 1970's in sufficient numbers to utilize the large quantities of plutonium available. Some plutonium will be required in the development of fast reactors and for loadings of the prototypes, but this is projected to be a small fraction of the total plutonium available in the 1970's. On this basis, the AEC's Plutonium Utilization Program objective is to develop by 1973 the base technology for safe and economic recycle of plutonium in thermal reactors, and more specifically in light water power reactors. The remaining technical uncertainties for plutonium recycle are primarily in the areas of fuels and physics. Consequently, these are the areas where the major research and development effort is being applied. These programs receive input from utilization studies which identify potential problem areas and incentives. The following sections of the report present recent results in fuels and physics development and plutonium utilization studies.
[en] This paper describes the experimental work undertaken in Italy on the irradiation of plutonium bearing fuel in thermal reactors. 16 MOX fuel assemblies were initially loaded into the Garigliano BWR and a further 46, a full reload, were loaded in 1975. Eight assemblies were loaded into the PWR at Trino Vercellese in 1976. Details of the fuel rod composition, burn up and post-irradiation examination results are given, together with a safety analysis
[en] It is currently accepted that plutonium must be recycled on a large scale in thermal power reactors in the period starting in 1974 even though the ultimate long term market for plutonium will be in breeder reactors. To meet this schedule, the economics and technology of plutonium recycle must be demonstrated on a commercial basis by 1971-1972 if fuel suppliers are to be in a position to supply warranted plutonium recycle assemblies for delivery in 1974. United Nuclear Corporation is conducting a research and development program to provide the base of analytical and experimental data, necessary for supplying plutoniumbearing reload assemblies in light water reactors. This program includes activities in the following areas: 1. Evaluations of plutonium recycle utilization strategy and core design. 2. Critical experiments on PuO2-UO2 lattices. 3. Demonstration of plutonium recycle in a utility power reactor. A summary of progress and plans in these areas is given in the following sections.
[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] Predictable effects of the recycle of plutonium and uranium recovered from spent LWR fuels were assessed in a final environmental statement (GESMO). Five alternative dispositions of LWR-produced plutonium ranging from prompt recycle of recovered plutonium and uranium to no recovery and no recycle are compared. The assessments consider cumulative effects for the period 1975 through 2000, and are centered on a conservative low growth rate resulting in about 500 LWR's in the U.S. in 2000. A more optimistic growth projection resulting in about 800 LWR's in 2000 is also analyzed in order to assess the effects of industry size upon the impacts. Demands for fuel cycle services were calculated with an ERDA program, NUFUEL, which was modified to include penalties for 236U and 242Pu. Unit cost data, including a simulation of market place reaction to supply-demand functions for uranium costs, were combined with the NUFUEL demand data in an economics code, NUCOST. Environmental impacts were also based upon NUFUEL demand data and were developed using a model plant industry concept. Using the most likely unit costs with a 10% discount rate, present worth incentives for prompt recycle over no recycle of $3.2 billion for the lower growth and about $6 billion for the higher growth were indicated. Present worth costs of delays in recycle of up to 5 years were less than $1 billion. Sensitivity of the economic assessments to unit cost variations and discount rates were also evaluated. Environmental impacts other than radiological were lowest for prompt Pu recycle and highest for no recycle. Radiological impacts for the total world wide total body exposure from U.S. industry for the 26 year period were estimated to be: - No recycle-8.2 million person-rem; U only recycle-9.5 million person-rem; Pu and U recycle-8.8 million person-rem. Comparison of the decreased radiological impact of the no recycle option with its increased costs relative to prompt plutonium recycle resulted in a cost/benefit ratio of 0.04. Thus, the benefits of prompt plutonium recycle appear to far outweigh its costs
[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] The paper is subdivided into four parts: the first considers the exploitation of the energy potential of nuclear fuel in proven-type reactors and in advanced converters; the second describes ENEL's program for plutonium recycle in thermal reactors; the third discusses the availability of plutonium from ENEL's reactors; and the fourth provides a few comments on the economics of plutonium utilization. The main interest in recycling plutonium in thermal reactors pending commercial operation of fast reactors undoubtedly lies in the possibility of using plutonium as an alternate fuel in lieu of enriched uranium and of increasing exploitation of the source material. The paper gives the natural uranium exploitation indexes expressed in MWYe/ton of Unat for a few proven-type reactors and converter reactors. The comparison of these indexes indicates that if plutonium recycling in thermal reactors is applied on a large scale, it will reduce natural uranium requirements for enriched uranium production by 30-40%. ENEL's program for the utilization of plutonium in thermal reactors is based on a research contract executed with EURATOM in 1966.
[en] In many countries, uranium is a major energy resource, fueling nuclear power plants that collectively generate about 17% of the world's electricity. With global demand for energy especially electricity projected to grow rapidly over the coming decades, the price and availability of all energy sources, including uranium, are key components in the process of energy planning and decision-making. Particularly affecting the uranium market were changing projections about nuclear power's growth and the consequent demand for nuclear fuel; the emergence of a more integrated free market system including former centrally planned economies; and the emergence into the civilian market of uranium released from dismantled nuclear weapons. All these factors contributed to uncertainties in the commercial uranium market that raised questions about future fuel supplies for nuclear power plants. Signs today indicate that the situation is changing. The world uranium market is moving towards a more balanced relationship between supply and demand
[en] This paper explains the reason for preferring in some instances figures collected by Working Group 6 for spent fuel arisings. A detailed table (Table 1) is attached. Table 2 makes a comparison between the figures given for cumulative WOCA spent fuel arisings in the OECD ''Yellow Book'' and from sub-group 1A/2A computer models