Opportunities to reduce consumption of natural uranium in reactor SVBR-75/100 when changing over to the closed fuel cycle
- FSUE SSC RF-IPPE, 1, Bondarenko sq., Obninsk, Kaluga rg., 249033 (Russian Federation)
The design of reactor SVBR-75/100 allows it to operate using different types of fuel and in different fuel cycles without changing its design and deteriorating its safety characteristics. Fuel-at-once refueling adopted in the design (lack of partial refueling) makes it possible to change the core content at each refueling by using the type of fuel that is the most economically effective at the current stage of nuclear power (NP) development. In the nearest future use of mastered oxide uranium fuel and operating in the opened fuel cycle with postponed reprocessing will be the most economically effective. Changeover to the mixed uranium-plutonium fuel and closed nuclear fuel cycle (NFC) will be economically effective in an event of increase of natural uranium costs when the expenditures for construction of the enterprises on reprocessing the spent nuclear fuel (SNF), re-fabrication of new fuel with plutonium and their operating are less than the corresponding costs of natural uranium, its enrichment costs, the costs of manufacturing fresh uranium fuel and long temporary storage of SNF. At this, it is possible to use both MOX fuel with weapon or reactor plutonium and mixed nitride fuel in case its usage is more profitable. As fast reactors (FR) using uranium fuel and operating in the opened NFC consume much more natural uranium in comparison with thermal reactors (TR), and at the expected high paces of NP development the cheap resources of natural uranium will be exhausted prior to the middle of the century that will cause increase in the uranium cost, the period of FRs operating in the opened NFC must be maximally reduced. However, it should be mentioned that it is difficult to forecast reliably the date when because of the increased cost of natural uranium the NP will lose its competitiveness with electric power using fossil fuel. This is conditioned by the fact that the cost of the NPP produced electricity is less sensitive to the cost of natural uranium in contrast to the cost of electricity produced by thermal power plants using fossil fuel. At the same time, the available resources of natural uranium are increasing progressively with increase of its cost. The expenditure caused by changeover to the closed NFC will be less, if plutonium extracted from the own SNF of uranium loads is used in fabrication of the first MOX fuel loads. If the oxide uranium fuel is used, by the end of the lifetime a comparatively high breeding ratio (BR) ({approx}0.84) provides a sufficiently high content of plutonium in the SNF that may be used in the next fuel lifetimes when organizing the closed fuel cycle. Moreover, the own SNF of starting loads from oxide uranium fuel contains large quantity of unburned uranium-235 that is expedient to use for forming load for the next lifetime. From the very beginning of realization of the extended program on implementation of reactors SVBR-75/100 in the NP, use of plutonium extracted from the TRs' SNF for forming the starting loads of those reactors for the purpose of total elimination of natural uranium consumption will be more expensive as compared with the considered variant of changeover from the opened NFC to the closed NFC. This is conditioned by the fact that for the plutonium extracted from the TRs' SNF, the plutonium cost determined by a volume of SNF reprocessing per ton of plutonium will be several times higher as compared with its cost in case of using the own SNF because of considerably less content of plutonium in the TRs' SNF. It should be taken into account that the organization of the enterprise on large-scale reprocessing of TRs' SNF and MOX fuel fabrication must precede the construction of NPPs with FRs. Thus, the demands in investments are increased. At the same time, for the proposed changeover from the opened NFC to the closed one the construction of the closed NFC enterprise may be long postponed from FR launching that reduces the investment demands. At this, as the assessments have revealed, the investment fund for construction of such enterprise could be formed during abo ut two years by including the corresponding component into the cost of electricity for the time after ending the pay-back period of the NPP at keeping the profitableness at the same level. That approach to organization of fuel cycles with full reprocessing of the own SNF will reduce considerably the integral consumption of natural uranium, and thus it will make the NPPs based on reactor installations (RI) of the SVBR type quite competitive with the NPPs based on TRs' RIs. In the closed NFC the TRs' SNF (both that of WWER and RBMK) can be used (utilized) as make-up fuel, instead of waste pile uranium without separation of uranium, plutonium, minor actinides and fission products (FP). The performed computations have revealed, that changeover to the closed NFC for FR SVBR-75/100 is possible to realize at the third lifetime i.e. in 16 years. At this, during the first 16 years the cumulative consumption of natural uranium calculated for 1 GWe will be {approx} 5670 tons. During the 60 years of the RI service lifetime, the consumption of natural uranium calculated for 1 GWe will be by 40 % less than its consumption by reactor WWER-1000 for the same time. The principal opportunity to use the TRs' SNF as make-up fuel when RI SVBR-75/100 is operating in the closed fuel cycle has been shown. At this, the TRs' SNF was only subjected to thermo-chemical processing with removal of gas and volatile FP. Adaptability of the SVBR-75/100 reactor relative to the fuel type and fuel cycle makes it possible to realize a timely and gradual changeover to the closed NFC, which will be economically justified. Simultaneously, the problems of utilization and radiation-equivalent burial of long-lived radioactive waste will be solved, with account that minor actinides are effectively burned in the FR. (authors)
- Research Organization:
- American Nuclear Society, 555 North Kensington Avenue, La Grange Park, IL 60526 (United States)
- OSTI ID:
- 20979687
- Resource Relation:
- Conference: Advanced nuclear fuel cycles and systems (GLOBAL 2007), Boise - Idaho (United States), 9-13 Sep 2007; Other Information: Country of input: France; 7 refs; Related Information: In: Proceedings of GLOBAL 2007 conference on advanced nuclear fuel cycles and systems, 1873 pages.
- Country of Publication:
- United States
- Language:
- English
Similar Records
The Complete Burning of Weapons Grade Plutonium and Highly Enriched Uranium with (Laser Inertial Fusion-Fission Energy) LIFE Engine
Use of Multi-Purpose Modular Fast Reactors SVBR-75/100 in Market Conditions