Transient extraction behavior analysis of reprocessing plant with SAFE code

SAFEコードによる再処理抽出過渡挙動解析

内山 軍蔵 ; 阿部 仁 

Uchiyama, Gunzo; Abe, Hitoshi

原子力機構では再処理施設の抽出工程において想定される異常な過渡変化事象の安全解析コードとしてSAFEコードを開発している。本報では、抽出工程、特にPu精製サイクルについてPu濃度異常上昇事象の発生とさまざまな運転操作条件変動との関係をSAFEコードを用いて検討した結果について報告する。

The simulation code, SAFE (Simulation code of anticipated transients formed extraction process), was developed in JAEA (Formerly JAERI) to obtain a highly functional tool based on a refined model that allows reliable safety assessment with reasonable safety margin of anticipated transient extraction behavior in reprocessing. Anticipated transient extraction behaviors of U and Pu have been studied with the SAFE code to understand the effect of process parameters in solvent extraction cycles in current large-scale reprocessing plants. In this paper the analytical results of transient extraction behaviors of Pu in the Pu purification cycle are mainly described. It was found that the concentration of Pu in the Pu stripping and Pu scrubbing steps increased with decreasing of the flow rate of nitric acid solution, which caused a Pu leakage from the Pu stripping to the Pu scrubbing and then the U stripping steps.