Advanced Nuclear Fuel Cycles And Nuclear Waste Disposal

Extracting transuranic elements from nuclear waste (partitioning - P) to burn them in dedicated nuclear reactors (transmutation - T) essentially holds the promise of reducing the one-million-year risk of highly radioactive nuclear waste disposal. That would solve one of the main conundrums of nuclear energy production. Here, we argue that P&T will not significantly change the safety requirements and risks of geologic disposal for spent fuel and high-level nuclear waste. We will assess the maturity of P&T technologies such as reactors, separation technologies and fuel fabrication plants. A sensitivity analysis will be presented on the time scale and effects of a P&T treatment of nuclear waste fuel cycle choices like fast reactor, molten salt reactors or accelerator driven systems. This will include an estimate of the number of required fuel cycle facilities, and the composition of the final waste stream, depending on separation and transmutation efficiency, irradiation and cooling down times and and the build-up of problematic fission products with very long half-lives. Emphasis will be on the isotopic changes in the actinide material streams especially the Plutonium isotopic vector during P&T cycles caused by multiple irradiation in a fast neutron spectrum. We compare homogeneous P&T strategies with improved proliferation resistance and heterogeneous P&T strategies with different actinides being treated separately in a more flexible fuel cycle design. The analysis will address proliferation and safety aspects.