Plutonium recycle

Concern about the potential diversion of separated reactor-grade plutonium has led to a reduction ia U.S. governmental support of development of both plutonium recycle and the Hquid metal reactor. This latter ultimately depends on chemical reprocessing to achieve its long-range purpose of generating more nuclear fuel than it bums ia generating electricity. 

Process Schematic. A schematic showing our main production sequence and residue recyle streams is seen in Figure 11. In addition on this figure, (shown in the pentagonal shaped boxes) are two proposed plutonium recycle streams which are under investigation but are not being used in the production sequence. 

Nenot JC, Stather JW. 1980. The toxicity of plutonium, americium, and curium Plutonium recycling in light water reactors. Oxford Pergamon Press. 

If nonproliferation considerations have not led to official opposition to nuclear power, their effect on fuel cycle policy has been profound. Although, its rhetoric and many of its implementating actions have been more restrained, the Clinton Administration has, in principle, adopted the Carter policy of opposition to reprocessing and plutonium recycle, hr at least one important area, however, it has inexplicably out-Cartered earlier policy by terminating work on proliferation-resistant firel cycles that involve recycle of still highly radioactive plutonium. 

Proliferation concerns have been and continue to be the basic cause ofthe official US. opposition to reprocessing and plutonium recycle, and have thus led to the official U.S. categorization of spent fuel as nuclear waste which should be permanently buried in geologic repositories. 

Fig. 16. Standard pattern of control assemblies in contemporary pressurized water reactor core. The pattern provides morc-than-sufficient control for self-generated plutonium recycle. For complete open-market plutonium recycle, 4-element control assemblies are added in positions marked S...

Two engineering system demonstrations were performed to reduce the uranium-from-ore requirements of LWRs recycle of the plutonium and conversion to the thorium-uranium cycle to achieve thermal breeding. The demonstration phase of the plutonium recycle development was carried out in seven power reactors. Several LWRs originally were started up on the thorium-uranium cycle, and a light... 

Figure 4. Fuel processing the flow sheets for lOOO-MW(e) pressurized water reactor (A) without and (B) with plutonium recycle. (After Ref. 8.)...

The concentration of plutonium in the filtrate, which is a measure of the completeness of precipitation and so the amount of plutonium recycle required, was determined coulometrical 1y. 

M. SPENT FUEL REPROCESSED, URANiUM AND PLUTONiUM RECYCLED Recovered Pu, 445 kg... 

Even with plutonium recycle, thus, this thermal reactor converts less than 1 percent of natural uranium to energy. This low uranium utilization results from the fact that the conversion ratio of to plutonium in a thermal reactor is less than unity. 

Because Fig. 3.31 without plutonium recycle shows a specific uranium consumption of 439.2 lb UgOg/(MWe year), plutonium recycle reduces UgOg demand by 27 percent. 

Because plutonium recycle makes possible the generation of 3074 MWe of electricity with only 2074 MWe nquiring enriched uranium, the reduction in separative work demand nude possible by plutonium recycle is (100X3074 — 2074)/3074 = 32.5 percent, and the specific separative work demand is (106,974X2.074)/3074 = 72.1 SWU/(MWe-year). This is to be compared with 106.974 SWU/(MWe year) without plutonium recycle. 

The specific consumption of UsOg and separative work in this HTGR cycle with recycle is compared in Table 3.16 with corresponding quantities for the LWR without or with plutonium recycle. 

The HTGR with recycle thus consumes about the same amount of separative work as the LWR with plutonium recycle, but uses only 65 percent as much natural uranium. 

The shorter time allowed for LMFBR fuel to cool is desirable for economic reasons to reduce the amount of plutonium inventory outside of the reactor. The rate at which plutonium is discharged from the LMFBR is eight times as high as from the uranium-fueled LWR (Fig. 3.31) and twice as high as from the LWR with plutonium recycle (Fig. 3.32). 

The effect of plutonium recycle is to increase the production of higher-mass isotopes of plutonium and of americium and curium, because the recycled plutonium is exposed to neutrons throughout the entire irradiation cycle. The actinide quantities calculated [PI] for the same 1000-MWe reactor operating on an equilibrium fuel cycle with self-generated plutonium recycle are shown in Table 8.5. The alpha activity of the plutonium processed yearly is increased by a factor of 14 by plutonium recycle, the americium activity is increased by a factor of 5, and the curium activity by a factor of 7. 

Because of the relatively small amount of high-mass plutonium nuclides produced in uranium-thorium fueling, the amounts of americium and curium produced are about two orders of magnitude less than in a uranium-fueled reactor with plutonium recycle. 

In a PWR operating with plutonium recycle the thermal-neutron flux is lower than for uranium fueling because of the hi er fission cross section for plutonium. As a result, less C is produced by thermal-neutron activation within the fuel, as drown in Table 8.11. 

Am will grow with time in plutonium recycled for fabricating reactor fuel, as discussed in Chap. 8. The gamma radiation accompanying the decay of Am will contribute external radiation and may require personnel protection. 

HLW from advanced fuel cycles. Advanced fuel cycles that will be considered are plutonium recycling and the LMFBR fuel cycle. There is little difference from LWR waste as far as fission... 

Nenot J, Stather J. 1979. The toxicity of plutonium, americium and curium. A report prepared under contract for the Commission of the European Communities within its Research and Development Programme on "Plutonium Recycling in Light Water Reactors." New York Pergammon Press, 1-9. 

Nevertheless, as in the long-term prospect the SNF reprocessing and plutonium recycling are necessary, the search and development of the most economically available, safe and ecologically pure processes of SNF reprocessing must be carried out within the required scales. 

Plutonium recycling is now an industrial reality in Europe. More than 20 reactors are already loaded with MOX fuel, representing more than 701 of Pu processed in Europe. 

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