Development of high-level liquid waste conditioning technology for advanced nuclear fuel cycle, 9; A Wash test using real insoluble residue

Morita, Yasuji  ; Yamagishi, Isao ; Iijima, Takahiko

Development of high-level liquid waste (HLW) conditioning technology for advanced nuclear fuel cycle was conducted for the purpose of the reduction of potential problems in the verification process for HLW. It includes development of separation technology for Mo, Pd and Ru from HLW and development of separate treatment of the insoluble residue. The method of washing the insoluble residue before solidification of the residue was studied using real insoluble residue obtained by dissolution of spent nuclear fuel. Washing by nitric acid and oxalic acid was found to contribute to the reduction of contamination with Zr and -emitters. Metal alloy component in the insoluble residue, Mo, Tc, Ru, Rh and Pd did not change its composition even after the washing.