Development of argon gas cleaning for sodium-cooled reactor spent fuel

ナトリウム冷却炉の使用済燃料ためのアルゴンガス洗浄の開発

近澤 佳隆  ; 加藤 篤志 ; 小幡 宏幸*

Chikazawa, Yoshitaka; Kato, Atsushi; Obata, Hiroyuki*

JSFRは革新技術として簡素化燃料取扱システムを採用している。その中の一つの技術として使用済燃料洗浄には従来の水洗浄に代えてアルゴンガスによる乾式洗浄を採用している。本報告では模擬燃料集合体による乾式洗浄試験の結果をまとめた。また、試験の結果から不確かさ等を考慮し実機における洗浄後のナトリウム付着量を評価した。

Japan Sodium-cooled Fast Reactor (JSFR) is going to adopt an advanced fuel handling system. From the viewpoint of spent fuel cleaning, a new dry cleaning process instead of the conventional process with water rinse is under developing. In this study, drain performance tests on the JSFR subassembly inner duct and dry cleaning performance tests with a full-scale mockup subassembly are summarized. Based on the experimental data of the inner duct and mockup subassembly tests, residual sodium on the spent fuel subassembly after argon gas cleaning has been evaluated to be 400g. Water alkalinity and purification performance has been evaluated and the JSFR water pool system has shown capability to accept 400g residual sodium on the spent fuel subassembly after argon gas cleaning.