Merits and Viability of Different Nuclear Fuel Cycles and Technology Options and the Waste Aspects of Advanced Nuclear Reactors (2023) / Chapter Skim
Currently Skimming:
2 Merits and Viability of Existing Nuclear Fuel Cycles for U.S. Light Water Reactors
2 Merits and Viability of Existing Nuclear Fuel Cycles for U.S. Light Water Reactors
Pages 31-52
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 31... ...
These multidecade investments have led to the development of more technically complex technologies; even then, it is still unclear that these technologies will be available by 2050. Some limited progress is apparent, such as Russia's BN-600 and BN-800 fast reactors and France's La Hague reprocessing facility for LWR spent fuel, but there are many more instances where development of alternatives to the LWR-based once-through fuel cycle has been halted or delayed for decades for various reasons, including cost proliferation and concerns.
|
From page 32... ...
spent fuel inventory remains the once-through nuclear fuel cycle, which is still not being fully implemented because of the political impasse over the Yucca Mountain geologic repository site in Nevada. No incentives presently exist for undertaking monorecycling in the United States, largely because of the high costs involved and the decreasing contribution by LWRs to the generation of electricity due to plant shutdowns; substantial challenges, based on past experience, for successful licensing and construction of spent fuel reprocessing and mixed oxide fuel fabrication installations; security and environmental concerns; and the abundance of natural uranium and uranium enrichment at relatively low costs for the foreseeable future.
|
From page 33... ...
The isotopic makeup of plutonium is a function of the composition of the starting material makeup and irradiation conditions. 5 The integral fast reactor would breed more fuel than EBR-II and would be distinguished by a nuclear fuel cycle that performs reprocessing via electrorefining (see Chapter 4)
|
From page 34... ...
Russia's experience with operating commercial-size fast reactors is described in Appendix H As noted above, recovery of plutonium from reprocessing spent LWR uranium oxide fuel is required to support the development and fueling of breeder reactors.
|
From page 35... ...
. 2.3 COMMERCIAL NUCLEAR FUEL CYCLE OPERATIONS SUPPORTING LIGHT WATER REACTORS The nuclear fuel cycle consists of the front end, which involves the preparation of the fuel; the service period, in which the fuel is used during reactor operations; and the back end, during which the spent fuel and nuclear waste is managed, stored, and disposed.
|
From page 36... ...
Nuclear Regulatory Commission to produce low-enriched uranium fuel that is sold worldwide: Global Nuclear Fuel-Americas in Wilmington, North Carolina; Westinghouse Columbia Fuel Fabrication Facility in Columbia, South Carolina; and Framatome, Inc., in Richland, Washington.
|
From page 37... ...
However, many of these utilities no longer use commercial reprocessing services, for a variety of reasons, including nuclear power phase-out policies and economic penalties deriving from the higher expense of reprocessing relative to spent fuel storage, the higher fabrication cost of plutonium-based mixed oxide fuels compared with uranium fuels, and the lack of prospects for plutonium reuse in fast reactors. Presently, France and Russia continue to reprocess, and Japan intends to do so in a facility located at Rokkasho.
|
From page 38... ...
. Loss of fissile plutonium-241 and buildup of americium-241 degrade the reactivity of the fuel in thermal and fast reactors, and increase worker dose during mixed oxide fuel fabrication.15 To mitigate the buildup of the plutonium inventory, reactor-grade plutonium can be substituted for enriched uranium, and fuel rods containing a mixture of depleted or natural uranium oxide and plutonium oxide (i.e., mixed oxide fuel)
|
From page 39... ...
As a result, some countries have chosen not to recycle reprocessed uranium and are storing it until its use becomes economically competitive.18 Countries that have exercised the fuel cycle option to reenrich and recycle reprocessed uranium in an LWR have successfully managed the radiological aspects of uranium-232 associated with handling reprocessed uranium during conversion, reenrichment, fuel fabrication for recycle, transportation, and fuel loading during reactor operations. Spent reprocessed uranium oxide is not presently scheduled for further reprocessing19 and will require storage until a decision is made to either reprocess or dispose of it in a geologic repository, when one becomes available.
|
From page 40... ...
Deterioration of the safety parameters21 beyond plutonium concentrations of ~12 percent becomes a safety barrier to multirecycling of plutonium in present-day LWRs.22 As a result, enriched uranium has to be added to the fuel for such a potential option. From the perspective of spent fuel assembly volume, each spent MOX assembly is obtained by reprocessing seven spent uranium oxide assemblies, thereby significantly reducing the number of spent fuel assemblies to be stored.
|
From page 41... ...
(2003) estimate that LLW handling and disposal could add several tens of dollars per kilogram of spent fuel, which is on the order of 1 percent of the cost of reprocessing (Bunn, 2021)
|
From page 42... ...
Spent fuel is stored as spent uranium oxide fuel, spent mixed oxide fuel, or spent reprocessed uranium oxide fuel, in either wet or dry environments, and either onsite with the reactor or at away-from-reactor sites. Interim storage of these spent fuel assemblies will be required until either a geologic repository is available for direct disposal or a decision is made to reprocess them.
|
From page 43... ...
FP = fission product; FR = fast reactor; LWR = light water reactor; MA = minor actinides; MOX = mixed oxide; UOX = uranium oxide; UrepOX = reprocessed uranium oxide. SOURCE: Icons adapted from MIT (2011)
|
From page 44... ...
See Chapters 3–5 for more details on sodium-cooled fast reactor technology. Reprocessing of fast reactor mixed oxide fuel: Fast reactor spent fuels will have higher fissile concentrations than LWR fuels and potentially higher burnups.
|
From page 45... ...
LIGHT WATER REACTORS 45 U.S. policies on reprocessing and recycling technologies: As mentioned in Section 2.2, abandonment of the commercial reprocessing of spent nuclear fuel in the United States in the mid-1970s, due to proliferation and economic concerns, set the path of U.S.
|
From page 46... ...
Past U.S. Department of Energy proposed justification for reprocessing and advanced fuel cycles: Around 1990, a new justification for reprocessing -- the benefit of waste disposal -- was promulgated for the U.S.
|
From page 47... ...
and the National Academies addressed the question "Would the benefits to radioactive waste disposal justify processing of existing spent LWR fuel and deploying liquid metal fast reactors to consume the separated transuranic elements? " Results from these studies tended to reach similar conclusions: • According to EPRI, adoption of a process-before-disposal policy for current spent fuel would accrue minimal benefits.
|
From page 48... ...
Thus, nuclear power contributes significantly to French industrial, energy, and environmental policies. Past experience and current policy on developing nuclear fuel cycles for multiple recycling of fissionable materials: Ensuring sustainable supplies of uranium has always been a top priority of French nuclear fuel cycle strategy.
|
From page 49... ...
separation and transmutation32 of long-lived radioactive materials in the spent fuel (including minor actinides and some fission products)
|
From page 50... ...
2.6 INSIGHTS ABOUT MERITS AND VIABILITY OF FUEL CYCLE OPTIONS FOR EXISTING LWR TECHNOLOGIES The two partial fuel cycles referred to as once-through and monorecycle were not anticipated to be options during the early days of nuclear power development and deployment. Spent LWR fuel was intended to be reprocessed rather than disposed of in a geologic formation, and recovered plutonium was intended to be recycled in fast reactors, rather than in LWRs, given the much better nuclear properties of plutonium in a fast neutron environment (i.e., in fast reactors)
|
From page 51... ...
existing spent fuel prior to disposal in a geologic repository. Similarly, storage approaches are being used for the spent mixed oxides, high-level waste, and other products created by monorecycling.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.