FaCT Phase I evaluation on the advanced aqueous reprocessing process, 5; Research and development of uranium crystallization system

Shibata, Atsuhiro  ; Yano, Kimihiko ; Sambommatsu, Yuji; Nakahara, Masaumi; Takeuchi, Masayuki ; Washiya, Tadahiro ; Nagata, Masanobu*; Chikazawa, Takahiro*

JAEA has been developing a U crystallization process. The development targets were DFs of over 100, confirmation of mechanical performance of crystallizer, and so on. Fundamental data were obtained by beaker-scale experiments with actual dissolver solution. DFs for most of the FPs are improved by washing. However the formation of Pu-Cs double salt causes low DF of Cs. To confirm the mechanical performance of an annular type crystallizer and a crystal separator, some experiments were carried out. The crystallizer and the separator have good performance. However washing of UNH crystals by the separator did not have the intended effect for solid impurities. We discussed the application of crystal purification technology to improve the purity and selected KCP. UNH crystal purification tests were carried out using bench-scale KCP apparatus with simulated solid impurities. The purifier has good performance on the decontamination of not only liquid impurities but also solid impurities.