Including spaces rational maintenance plan on decommissioning in FUGEN

ふげんにおける廃止措置中の原子炉施設の保全について

山本 恭士; 松尾 秀彦; 宮下 進市

Yamamoto, Takashi; Matsuo, Hidehiko; Miyashita, Shinichi

新型転換炉原型炉ふげんは、約25年間の運転実績を積み、2003年3月に運転を終了した。現在、廃止措置は第2段階(原子炉周辺設備解体撤去期間)に移行している。設備の保全は、使用済燃料の貯蔵に係る設備等、機能維持が必要な設備に対し点検計画に従った確実な点検の実施と共に、継続的な合理化を図っている。本件では、廃止措置中のふげん原子炉施設における、保守管理や設備維持に係る合理化及び改善等について報告する。

Fugen is a heavy water-moderated, boiling light water-cooled, pressure tube-type reactor with the electrical power of 165 MW. It had been operated for 25 years from March 1979 to March 2003. After ceasing its operation, decommissioning project started 2008. Currently, FUGEN is the second phase of decommissioning (Reactor Periphery Facilities Dismantling Period). Fugen in decommissioning has the risk decreased than in operation. Therefore, it have been rationalizing maintenance continuously. At the paper, report on the rationalization and improvements of the maintenance in decommissioning. After ceasing the operation, all of the spent fuels were removed from reactor to the spent fuel pool. And now, the spent fuels has low heat generation and it is not necessary to remove the heat. Therefore, we are continuing to rationalize the maintenance plan depending on the situation of decommissioning.