著者

池田 佳隆 岡野 文範 逆井 章 花田 磨砂也 秋野 昇 市毛 尚志 神永 敦嗣 清野 公広 久保 博孝 小林 和容 笹島 唯之 助川 篤彦 千葉 真一 西山 友和 三代 康彦 柳生 純一 横倉 賢治 JT-60 チーム

出版者

Atomic Energy Society of Japan

雑誌

日本原子力学会和文論文誌 (ISSN:13472879)

巻号頁・発行日

vol.13, no.4, pp.167-178, 2014 (Released:2014-11-15)

参考文献数

14

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The upgrade of JT-60U to the superconducting tokamak “JT-60SA” has been carried out as a combined project of JAEA's program for national use and the Satellite Tokamak Program in collaboration with EU and Japan fusion communities. The JT-60U torus was dismantled so as to install the new JT-60SA torus at the same position in the torus hall. JT-60U used deuterium for 18 years, so the neutron yield reached about 1.5×1020 (n) in total. The dismantling project of JT-60U was the first decommissioning experience of a fusion device with radioactivity in Japan. The project was intended to demonstrate decommissioning technologies and work activities, and to acquire experience and data on the technologies as well as to implement the dismantling project safely. Moreover, all disassembled components were stored with the data such as dose rate, weight and kind of material being recorded, so as to apply the clearance level regulation in the future. The lessons learned from the dismantling project indicated that the cutting technologies and storage management of disassembled components were the key factors in conducting the dismantling project efficiently. After completing the dismantling project, efforts have been made to analyze the data for characterizing disassembling activities, so as to contribute to the estimation of manpower needs and the radioactivity of the disassembled components from other fusion devices.