次世代燃料サイクルのための高レベル廃液調整技術開発,19; 不溶解残渣の溶解速度の組成依存性

Development of high-level liquid waste conditioning technology for advanced nuclear fuel cycle, 19; Dependence of dissolution rate of insoluble residue on its composition

宇佐見 剛*; 塚田 毅志*; 山岸 功 ; 森田 泰治  

Usami, Tsuyoshi*; Tsukada, Takeshi*; Yamagishi, Isao; Morita, Yasuji

不溶解残渣を長時間、硝酸中に浸漬した場合の溶解速度と、残渣組成等の関係を、模擬不溶解残渣として、Ruを主とし、Mo, Pd, Rhを含む合金を用いて調べた。不溶解残渣中のPdが増加すると溶解速度は大きくなり、Ruが増加すると溶解速度は小さくなった。すなわち、不溶解残渣中のPdが溶解を促進し、Ruが溶解を抑制することが示された。

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. To evaluate characteristics of the insoluble residue, simulated residue of metal alloy composed of Ru, Mo, Rh and Pd was dissolved with heated nitric acid. The results showed that higher concentration of Pd in the alloy makes the alloy easier to be dissolved, and higher concentration of Ru makes the alloy more difficult to be dissolved.