Evaluation and improvement on external-hazard proof of JSFR fuel handling system

JSFR燃料取扱設備における外部起因事象耐性評価

加藤 篤志 ; 近澤 佳隆  ; 鵜澤 将行*

Kato, Atsushi; Chikazawa, Yoshitaka; Uzawa, Masayuki*

福島事故を受けて、地震及び津波に対するJSFRの燃料交換設備の耐性評価を実施した。耐震評価では、福島地震を包絡する条件で機器の健全性を評価し、津波評価では、安定した冷却状態に導くシナリオを評価するとともに、全電源喪失時の実力評価を実施した。評価の結果、これら外部事象が襲った際も、外部への放射性物質の放出を防ぐ実力がJSFRにはもともと備わっていたことが明らかにされた。

Responding to the Fukushima Dai-ichi Nuclear Power Plant (1F-NPP) accident, the earthquake and the tsunami proof of the fuel handling system (FHS) in Japan Sodium-cooled Fast Reactor (JSFR) is studied. In the earthquake proof estimation, the margin of seismic resistance against the earthquake of the 1F-envelop condition and the sloshing behavior in the EVST is estimated. In terms of the tsunami proof, the scenario to lead fuel subassemblies into the stable cooling state and the potential of the cooling system is introduced in case of loss of the emergency power supply. As a result, it is clear that JSFR FHS originally could already be prepared to have the potential to prevent the release of radioactive material.