Tritium Removal Experience in TFTR and JET

An excellent discussion of the various techniques used - and their effectiveness - to remove tritium from TFTR and JET during and subsequent to the D-T operation phases is available in [29]. Here we shall provide a brief summary. The techniques that were found to be effective in removing tritium from either one or both machines are listed in Table 10.1. 

The Tokamak Fusion Test Reactor was the first fusion facility with extensive experience with tritium fuelling and removal. During the 3.5 years of D-T operation, 3.1 g T was supplied to the plasma by neutral beam injection and 

1 g by direct gas puffs, for a total of 5.2 g T. There were three periods of 

Techniques of tritium removal from co-deposited layers in next-generation tokamaks, such as ITER, have an important impact on machine operation. Attempts are being made to develop in-situ co-deposit removal techniques that would not overly constrain machine operation, both in terms of T removal and plasma performance recovery after cleanup. In addition to machine operation considerations, the tritium in the co-deposited layers will also have safety implications. During a severe accident, the vacuum vessel of an operating tokamak can be breached. If a significant inventory of tritium in the form of a saturated layer is present, much of this tritium can be released as tritium oxide as the film reacts with oxygen. 

Laser heating Can be used without oxygen. Needs electro-mechani- 

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