Internationalization of the Nuclear Fuel Cycle Goals, Strategies, and Challenges (2009) / Chapter Skim
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3 FUEL REGENERATION OPTIONS TO SUPPORT AN INTERNATIONAL NUCLEAR FUEL CYCLE
3 FUEL REGENERATION OPTIONS TO SUPPORT AN INTERNATIONAL NUCLEAR FUEL CYCLE
Pages 57-88
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From page 57... ...
, the plutonium and uranium recovery by extraction (PUREX) process, and other processes being considered by the Russian Federal Agency for Atomic Energy for separation of fissile and other materials from spent or irradiated nuclear fuel.
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From page 58... ...
Each system can be compared based on its life-cycle electricity cost. Additional criteria may include the degree of uncertainty of those cost estimates; the system's contribution to the costs of spent fuel and nuclear waste management; initial capital costs and the resulting level of financial risk in implementing and operating a system; the variability and reliability of the electrical output; and the system's attractiveness or unattractiveness to the private sector (along with the scope of required government subsidies or regulations needed to make the system competitive)
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From page 59... ...
2 For a discussion of similar criteria, see Bunn 2007, and Nuclear Energy Agency for the Generation IV International Forum, 2006.
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From page 60... ...
Advanced safeguards and security technologies could play a critical role in pursuing the nonproliferation goals mentioned above. In particular, in providing increased capabilities to detect covert nuclear facilities; highly accurate near-real-time monitoring of material flows in bulk processing plants with reduced intrusiveness, increasing confidence that any diversion would be detected; low-cost real-time monitoring that would set off an immediate alarm if stored nuclear material were tampered with or removed; effective protection against sophisticated outsider and insider theft and sabotage threats at reduced cost; and design of facilities to simplify and increase the effectiveness of safeguards.
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From page 61... ...
term "unirradiated direct-use material," which refers to direct-use material (including chemical mixtures such as MOX) "which does not contain substantial amounts of fission products; it would require less time and effort to be converted to components of nuclear explosive devices" than would, for example, plutonium in spent nuclear fuel.
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From page 62... ...
EVALUATING CURRENTLY PROPOSED SYSTEMS Nations that have led technological development of nuclear fuel cycles, including France, Japan, Russia, the United Kingdom, and the United States, have developed a variety of technological options for processing spent nuclear fuel. Some processes, including the only ones deployed on a large scale, initially were developed and optimized for the military purpose of extracting plutonium for nuclear weapons.
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From page 63... ...
U.S. process: Spent fuel, if oxide, is reduced to a metallic form and immersed in a bath of molten salt floating on a liquid cadmium cathode, which attracts plutonium and the minor actinides.
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From page 64... ...
- UREX+3 LWR mixed oxide Glovebox High UREX+3 FR mixed oxide or metal Glovebox High UREX+3 Am/Cm transmutation target Remote, hot cell Low UREX+4 LWR mixed oxide Glovebox High UREX+4 FR mixed oxide or metal Glovebox High UREX+4 Am transmutation target Remote, possibly Low glovebox UREX+4 Interim storage of Cm - † SOURCE: Finck, 2006.
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From page 65... ...
The material recovered from the Russian process, sometimes called dirty fuel in Russia, includes 4 "The characteristics, treatment, and final disposition requirements of several waste streams from spent fuel reprocessing is not completely known at this time. This is because (a)
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From page 66... ...
The joint committees' statement of task also calls for a comparison of the Russian BN600 and BN-800 fast reactors to the types of fast reactors under consideration in the U.S. Global Nuclear Energy Partnership (GNEP)
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From page 67... ...
Recommendation 8 Developers of nuclear fuel cycle technologies should assess the technologies' proliferation risks and projected economic costs and benefits as critical elements of design. As new technologies are developed, it will be important for developers to consider the proliferation hazards and work with the IAEA to develop appropriate safeguards.
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From page 68... ...
A reactor using fuel initially loaded with 15 percent plutonium that reaches high fuel burn-up, for example, 135,000 MWd/MTHM (around 15 percent burn-up) , may still have substantial amounts of plutonium and other actinides in the spent fuel.
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From page 69... ...
The present commercial nuclear fuel cycle includes the mining and extraction of uranium, the purification of uranium ore, the conversion to uranium hexafluoride, uranium enrichment, fuel fabrication (including the conversion of uranium hexafluoride to uranium dioxide)
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From page 70... ...
First among the observations is that these topics are not areas of technology that will advance without directed research specifically focused on the nuclear fuel cycle; advances in other areas of science and engineering will help, but are not sufficiently linked to nuclear fuel cycles to solve the technical challenges described here. Research is needed in the areas of processing of irradiated nuclear fuel and nuclear fuel design, as well as in improved approaches to disposal of wastes or spent fuel, and reduced-cost recovery of uranium from low-grade sources.
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From page 71... ...
; thorium fuel cycles; dry methods for fuel separations; and economic new sources of uranium. IMPROVED FAST REACTORS It may be possible to show that some fast-reactor designs would not require some of the safety systems required for LWRs.
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From page 72... ...
All commercial, light-water power reactors worldwide have historically been built at the site of operation and are refueled by opening the reactor, removing fuel that is spent and placing it in temporary storage, and loading the reactor core with fresh fuel. For a typical light-water reactor core, the reactor must be shut down every 18 or 24 months to change out one-third of the fuel.
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From page 73... ...
A remote community in Alaska in the United States is considering purchasing one of these power systems.12 TABLE 3-1 Small Reactors Power Capacity Small NPP Electricity, Cogeneration Refueling Fuel MW interval, years enrichment, % Electricity, Heat, Gcal/h MW ABV-6 2x8.5 2x6 2x12 12 19.5 SVBR-10 2x12 2x6 2x25 12 18.7 Uniterm 2x6.6 2x2.5 2x17.2 25 19.5 KLT-40C 2x38.5 2x19.5 2x73 3 17.4 Ruta - - 60.2 3 3 VVER-300 300 220 450 2 3.3 VBER-300 2x340 2x215 2x460 1.5 19.5 VK-300 - 250 400 2 4 SVBR-100 4x101.5 4x95 4x130 8 16.5 4S 1x10 30 Pu-10% SOURCE: Adapted from IAEA 2005a. HIGH BURN-UP FUELS Advanced fuel technologies could have an impact on the options available for nuclear fuel cycles in that they are essential to the technical feasibility of several of the options.
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From page 74... ...
Setting aside economic viability of these systems, design and fabrication of such fuel has been identified as the greatest technical challenge for fuel cycles considered under the advanced nuclear energy development program proposed in the United States in recent years. A system that retains the higher actinides within the fuel materials to reduce the direct usability of the materials streams in weapons and to reduce the actinide content of the waste streams faces the challenge of creating fuels that have never been fabricated and run before.
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From page 75... ...
However, this success is relevant only to a metal fuel alloy that is thermodynamically stable when in contact with sodium, which illustrates the point about a systemsdesign approach. In addition to the fuel matrix itself, other fuel materials must be able to perform reliably throughout the fuel's residence within the reactor core.
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From page 76... ...
Introduction of thorium fuel cycles would tap those resources for power generation and could reduce the waste disposal and proliferation hazards of nuclear power engineering, depending on how such cycles were implemented. Neither uranium-233 nor plutonium is found in significant quantities in nature, and so they must be produced in a reactor to acquire enough material to fuel a reactor.
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From page 77... ...
"Dry" technologies of a thorium fuel cycle can be based on the following processes: • hydrogenation of metallic fuel • chlorination of metallic and oxide fuel • sublimation and vacuum distillation of thorium and uranium tetrachlorides • electrolysis of molten salts • concentration of minor actinides and fission products • production of fuel compositions, fuel elements, and fuel assemblies These options are summarized in Table 3-2, which presents the types of reactors to be implemented during both stages of thorium fuel cycle development in Russia, and the purpose of reprocessing the blanket and core fuel.
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From page 78... ...
DRY METHODS FOR FUEL SEPARATIONS The Russian nuclear effort in dry methods for separation of nuclear fuel constituents is divided into two main categories: (1) pyroelectrochemical, which are the most compact, but provide only partial separation and purification; and (2)
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From page 79... ...
Russian pyrochemical reprocessing consists of three main stages: 1. dissolution of initial products or spent nuclear fuel in molten salts 2.
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From page 80... ...
Finding 10 Many of the technologies for improved nuclear fuel cycles are not areas that will advance without directed research specifically focused on the nuclear fuel cycle; advances in other areas of science and engineering will help, but are not sufficiently linked to nuclear fuel cycles to solve the technical challenges described here by themselves. Research is needed in the areas of processing of irradiated nuclear fuel and nuclear fuel design (beyond the incremental improvements in uranium oxide fuel for light water reactors)
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From page 81... ...
Although it is often argued that a closed fuel cycle reduces the volume of waste from nuclear energy, the amount of radioactive material requiring long-term storage depends upon the processes, the country's regulatory requirements, and even the definitions of waste.16 Pool storage for 5 years followed by dry cask storage has been approved by the U.S. Nuclear Regulatory Commission as being safe storage for many decades.
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From page 82... ...
COMPARISON OF PROCESSES FOR SEPARATION OF FISSILE AND OTHER MATERIALS FROM SPENT OR IRRADIATED NUCLEAR FUEL Currently operating reprocessing plants all use variations on the PUREX process. In this process, spent nuclear fuel is chopped and cladding hulls are separated.
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From page 83... ...
; see Box 3.5) with Russia and any other nation that is critical to the successful implementation of international fuel cycles involving transfer of spent nuclear fuel.
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From page 84... ...
law, such take-backs would require congressional approval, though they are not prohibited in principle; such approval is unlikely to be forthcoming, except in special cases, such as the ongoing return of irradiated research reactor fuel, which is part of a program to reduce proliferation risks by eliminating highly enriched uranium (HEU) from as many research reactors as possible.
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From page 85... ...
Section 123 of the AEA requires that the following key conditions and requirements be included in a U.S. agreement for peaceful nuclear cooperation:ª • a guarantee by the cooperating party that safeguards will be maintained with respect to all nuclear materials and equipment transferred, and with respect to all special nuclear material used in or produced through the use of such nuclear materials and equipment • a guarantee that no nuclear materials and equipment or sensitive nuclear technology will be used for any nuclear explosive device, or for research on or development of any nuclear explosive device, or for any other military purpose • except in agreements with nuclear weapon states, a stipulation that the United States shall have the right to require the return of any nuclear materials and equipment transferred to the recipient country and any special nuclear material produced through the use thereof if the cooperating party detonates a nuclear explosive device or terminates or abrogates an agreement providing for International Atomic Energy Agency safeguards • a guarantee that any material or any restricted data transferred pursuant to the agreement and, except in specific cases, any production or utilization facility transferred pursuant to the agreement or any special nuclear material produced through the use of any such facility or through the use of any material transferred pursuant to the agreement, will not be transferred to unauthorized persons or beyond the jurisdiction or control of the cooperating party without the consent of the United States • a guarantee that adequate physical security will be maintained with respect to any nuclear material transferred and with respect to any special nuclear material used in or produced through the use of any material, production facility, or utilization facility transferred • a guarantee that no material transferred and no material used in or produced through the use of any material, production facility, or utilization facility transferred will be reprocessed, enriched, or otherwise altered in form or content without the prior approval of the United States
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From page 86... ...
The Russian Federation and the United States signed an agreement on nuclear energy cooperation, which the United States considers a 123 agreement, on May 6, 2008. Approval and enactment of a 123 agreement does not require the approval of Congress, but Congress may enact legislation to disapprove the agreement.
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From page 87... ...
Both have invested a great deal of time and energy in developing concepts to advance the concept of a safer, more secure international nuclear fuel cycle program. Russia and the United States are able to conduct civilian nuclear energy cooperation with the other leaders in nuclear energy, but not with each other, and the lack of a U.S.-Russian agreement restricts those partners' cooperation on nuclear energy with Russia and the United States.
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