Limitations of actinide recycle and fuel cycle consequences: A global analysis part 1: Global fuel cycle analysis

Actinide recycle is realised in the conventional closed fuel cycle by reprocessing of spent LWR-UO₂ fuel and reuse of plutonium as LWR-MOX fuel. Recycling of actinides from spent LWR-MOX fuel is technologically more difficult because of the higher plutonium inventory and the occurrence of 5 times higher Pu238 levels and 10 times higher Cm244 concentrations. The minor actinides (Np, Am, Cm) resulting from reprocessing are transferred to the high level waste (HLW) and constitute the most important long term (> 500 years) radiotoxicity. Partitioning and transmutation (P&T) of minor actinides (M.A) is a very challenging option which could drastically reduce the long term radiotoxicity of vitrified HLW. Up to now very little attention has been given to the fate of uranium recovered from reprocessing or left over from the enrichment process. Though the separation of Np237 is technically possible its radiological significance is however negligible when compared to reprocessed or depleted uranium. Recycle of all trans uranium actinides is a very lengthy process, which may last up to 200 years, whose final outcome is compared with that of natural decay. In conclusion it is mentioned that within the P&T option emphasis should be put on the separation of the Am-Cm fraction from HLW which displays the highest radiotoxicity during the first 4000 years of disposal.