Regular Articles

Full Text / References

Conceptual Design of Temporally Storage Area in Hot Cell for Fusion DEMO Reactor

Masatoshi KONDO¹⁾, Youji SOMEYA²⁾, Mitsuyo TSUJI³⁾, Satoshi YANAGIHARA⁴⁾, Hiroyasu UTOH²⁾, Takashi KATO, Kenji TOBITA²⁾ and Shinzaburo MATSUDA¹⁾

1)

Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8550, Japan

2)

Japan Atomic Energy Agency, 2-166 Omotedate, Obuchi, Rokkasyo, Aomori 039-3212, Japan

3)

Tokai University, 4-1-1 Kitakaname, Hiratuka, Kanagawa, 502-5292, Japan

4)

University of Fukui, Fukui 914-0055, Japan

(Received 22 November 2015 / Accepted 26 March 2016 / Published 30 June 2016)

Abstract

In the maintenance procedure of fusion DEMO reactor, used in-vessel components are removed from the reactor vessel to be replaced. The temporally storage area for the used blanket segments is necessary. In the present work, the temporally storage area is conceptually designed as the used segments are stored dispersively in the plural compartments in the hot cell for the following dismantling procedure. The space dose rate of the compartment, where more than one segment is installed, was evaluated by means of the gamma ray transport calculation with PHITS Monte Calro analysis code. The space dose rate in the compartment decreases with time. For example, by the temporally storage of five used segments in one compartment for 20 years, the space dose rate in the compartment becomes lower than 250 Gy/hr, which is the limited value proposed for the remote handling in the ITER. The decay heat of the segments during the temporally storage is removed by flowing He. The segments are cooled at the temperature lower than 550 °C. Then, the used back plates can be reused in the other operation of the reactor, since the mechanical properties of the back plates are not affected by the heat treatment during the temporally storage.

Copyright (c) 2016 The Japan Society of Plasma Science and Nuclear Fusion Research

Keywords

hot cell, segment, waste management, low-level waste, remote handling

DOI: 10.1585/pfr.11.2405077

Full Text

PDF format (1.7Mbytes)

References

• [1] Y. Seki, I. Yamauchi, K. Yamada and H. Kawasaki, J. Fusion Energy 3, No.4, 241 (1983).
• [2] Y. Seki, I. Aoki, N. Yamano and T. Tabara, J. Fusion Energy 16, No.3, 205 (1997).
• [3] K. Tobita, S. Nishio, S. Konishi and S. Jitsukawa, J. Nucl. Mater. 329-333, 1610 (2004).
• [4] Y. Someya, K. Tobita, S. Yanagihara, M. Kondo, H. Utoh, N. Asakura, K. Hoshino, M. Nakamura and Y. Sakamoto, Fusion Eng. Des. 89, 2033 (2014).
• [5] Y. Someya, K. Tobita, M. Kondo, S. Yanagihara, H. Utoh, N. Asakura, K. Hoshino, M. Nakamura and Y. Sakamoto, In proceedings of Plasma 2014, 21pE-1, Niigata, Japan, Nov. 18-21 (2014).
• [6] T. Maruyama, Y. Noguchi, N. Takeda and S. Kakudate, Plasma Fusion Res. 10, 3405010 (2015).
• [7] H. Utoh, K. Tobita, Y. Someya and H. Takase, Fusion Eng. Des. 87, 1409 (2012).
• [8] M. Coleman, N. Sykes, D. Cooper, D. Iglesias, R. Bastow, A. Loving and J. Harman, Fusion Eng. Des. 89, 2347 (2014).
• [9] Y. Torikai, R.-D. Penzhorn, in proceedings of 10th international conference on tritium science and technology, Nice, France, Oct. 21-25 (2013).
• [10] Repair/maintenance remote handling equipments design for tokamak experimental fusion reactor, JAERI-M 8370 (1979).
• [11] Draft guide line and review for concrete for container vessel of nuclear power plant, Architectural Institute of Japan (in japanese) (1978).
• [12] An experimental study on mechanical properties of concrete exposed to high temperature conditions for eight years, CRIEPI, Abiko Research Laboratory Report, No. U95037 (1996).