Detaching test on an irradiated mock-up contaminated with tritium from the core of JMTR

Tomita, Kenji; Tsuchiya, Kunihiko ; Onuma, Yuichi; Inoue, Shuichi ; Watanabe, Hiroyuki; Saito, Takashi; Kikuchi, Taiji; Hayashi, Kimio; Kitajima, Toshio

The second in-situ irradiation experiment using a mock-up (ORIENT-II, JMTR capsule Number: 99M-54J) with a tritium breeder (LiTiO) pebble bed in the Japan Materials Testing Reactor (JMTR) was finished on Aug. 1, 2006. Consideration on the detaching procedure of the irradiated mock-up contaminated with tritium with pebble bed and a detaching test of this mock-up was carried out. The tritium removal properties were examined in the irradiated mock-up, the sweep gas tube, the protective tube and the junction box, for the decreasing of the tritium release to the area of detaching test. Melting/enclosed tests of sealing plug were also carried out for the prevention of tritium leakage from sweep gas lines of pebble bed. Then, the detaching test of the pebble bed was carried out. This report describes the results of tritium removal tests, examination of the detaching procedure, and the detaching test, as well as knowledge obtained from these tests and works.