Development of tritium production technology in nuclear fusion research program of Japan

Gaseous tritium was extracted from neutron-irradiated lithium aluminum alloys (6LiAl), containing 1% of 6Li enriched to 95%, by the use of Tritium Extraction System (TREX), a small scale test plant, constructed in the Japan Atomic Energy Research Institute (JAERI). TREX is a vacuum system made of stainless steel and consists of a vacuum furnace, a purifier, a tritium getter trap, and constant volumes to which analytical equipments are connected. The system was set in an airtight box surrounded with lead bricks of 5 cm thick. For the safe operation, Tritium Removal System (TRS) was furnished in the laboratory. TRS can remove tritium diffusing out of TREX into the atmosphere in the box by converting tritiated species to HTO, which is adsorbed on molecular sieves. TRS was operated at the flow rate between 1 and 7 m3h-1 and the appropriate decontamination factor of 104 was obtained in the test operation of a once-through mode