Comparison of sodium-cooled reactor fuel-handling systems with and without an ex-vessel storage tank

EVST方式と水プール直接貯蔵方式の燃料取扱設備比較評価

近澤 佳隆  ; 鵜澤 将行*; 臼井 伸一*; 戸澤 克弘*; 小竹 庄司

Chikazawa, Yoshitaka; Uzawa, Masayuki*; Usui, Shinichi*; Tozawa, Katsuhiro*; Kotake, Shoji

ナトリウム冷却実用炉のための燃料取扱設備の比較評価を実施した。簡素化EVST方式と水プール直接貯蔵方式の比較評価を実施した。水プール直接貯蔵方式はEVSTを削除可能なものの新燃料,破損燃料のための専用貯蔵設備を要しシステム全体としては経済性はEVST方式と同等程度であることがわかった。このため従来技術の延長で水プール直接貯蔵方式と同等の経済性を達成可能なEVST方式を採用した。

JSFR is a concept of a commercial sodium-cooled fast reactor which has been being studied in Fast Reactor Cycle Technology Development (FaCT) project since 2006. For the JSFR fuel handling, various fuel handling systems (FHSs) were investigated and an advanced FHS with an ex-vessel storage tank (EVST) has been selected. The other FHS concepts investigated are evolutional FHSs without an EVST. The result has indicated that the construction cost of the evolutional systems do not reduce the construction cost dramatically, which is mainly due to additional safety measures required higher decay heat handling in gas atmosphere and due to the necessity of separated fresh and failed fuel storage. From an economical point of view, a longer plant outage of the evolutional systems offsets its advantage of the lower construction cost. On the basis of the results of this comparative study, JSFR has selected the FHS with an EVST.