Research and development of crystal purification for product of uranium crystallization process

Yano, Kimihiko ; Nakahara, Masaumi; Nakamura, Masahiro  ; Shibata, Atsuhiro  ; Nomura, Kazunori  ; Nakamura, Kazuhito*; Tayama, Toshimitsu; Washiya, Tadahiro ; Chikazawa, Takahiro*; Kikuchi, Toshiaki*; Hirasawa, Izumi*

The behaviors of impurities and applicability of sweating and melting-filtration operations to the purification for UNH crystal were investigated experimentally on a beaker and an engineering scale. With regard to behaviors of impurities, the conditions of cesium and barium precipitation were surveyed and it was clarified that there were most impurities on the outside of UNH single crystal and that they make no eutectoid with UNH. On the other hand, it is confirmed that sweating and melting-filtration operations were effective in principle by the experiment with uranium and simulated FP system. After that, its effects verified by beaker scale experiments with the system including plutonium and irradiated fuel. Additionally, engineering scale tests were carried out with a Kureha Crystal Purifier (KCP) type testing device to evaluate that its performance was suitable for UNH purification. This work was supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan (MEXT).