Community Research and Development Information Service - CORDIS


The Exhaust Detritiation System (EDS) of the JET Active Gas Handling Plant has operated continuously for the last three years. The system has been used during the active commissioning phase, during the DTE1 deuterium-tritium experiment and subsequently during the Remote Tile Exchange (RTE) operation. The Exhaust Detritiation System is one of the key safety systems which permits the operation of the JET machine with tritium. This paper describes the experience gained of operating The erosion of soft a C:D films by heat treatment in air and under vacuum is studied by ion-beam analysis. When the films are heated in air above 500 K, the film thickness and the areal densities of C and especially D decrease, and oxygen is incorporated in the films. The initial atomic loss rates of carbon and deuterium from the films are 2.6 x 10 (17) C atoms cm (-2)h (-1) and 4.8 x 10(17) D atoms cm(-2)h(-1) at 550 K. However, after D depletion the films show a resistivity against further erosion due to annealing in air. When the films are heated under vacuum erosion starts at about 600 K and all components including D decrease proportionally to the film thickness. Thermal desorption spectroscopy of the films reveals the evolution of CxDy type hydrocarbons. Infrared analysis shows that the incorporated oxygen is chemically bonded to carbon. The thermally-activated decomposition of the soft a C:D films is compared to that of hard a C:D films and a reaction scheme is suggested.the Exhaust Detrititaition System throughout the tritium operations at JET. The design [1] and the construction and commissioning [2] of the Exhaust Detritiation System have been discussed previously.

Additional information

Authors: JET (GB), JET Joint Undertaking, Abingdon (GB)
Bibliographic Reference: Article: JET Papers presented at the 20th Symposium on Fusion Technology (SOFT-20), JET-P(1998)60, 1-183
Record Number: 199910519 / Last updated on: 1999-03-26
Original language: en
Available languages: en