Research on actinide elements related to nuclear fuel cycle in CRIEPI

In CRIEPI, research and development have been carried out on the basis of the fundamental strategy that as for technically ripe LWR fuel cycle. TRU is separated by dry process from the high level waste liquid generated by the reprocessing of LWR fuel as carried out currently, and as for FBR cycle, the nuclear fuel cycle is completed by dry process reprocessing of spent fuel as metallic fuel cycle. The feature of the fuel cycle the CRIEPI aims at is the confinement in metallic fuel FBR cycle including the TRU generated from LWR fuel cycle, accordingly, the fuel cycle becomes actinide fuel cycle. The dry process technology of separating TRU and its features, and the evaluation of the realizability of the metallic fuel containing minor actinides are described. The acquisition of thermodynamic data, the measurement of distribution coefficient, electrolytic separation test and the electrolytic processing technology for spent salt have been investigated. In the dry process separation, the quantity to be treated can be drastically reduced, and the scale of process can be made compact, and the construction cost is reduced. The characteristics and the irradiation test of minor actinide-containing fuel are reported. (K.I.)