H-Isotope Removal from C-Based Co-deposits

It is evident that the removal of tritium from the torus of ITER-like machines requires the removal of tritium from the co-deposited layers, or perhaps - depending on the technique used - the removal of the co-deposits themselves. Notwithstanding the observation that tritium retention in short-pulse machines will be affected by mechanisms other than co-deposition, the experience gained from TFTR and JET - the only tritium-burning tokamaks in the world - is of paramount importance for gaining some understanding of the T-removal processes. Here we present a brief review of the T-removal experience with TFTR and JET, and then review controlled laboratory and 

D tokamak pulses Ineffective Tokamak pulses in D (few thousand) reduced the in-vessel inventory at end of DTE1 by a factor of 2. 

ICRF not applied Pulses with RF heating helped to remove significantly more T than ohmic pulses. Wall inventory was reduced from 4.4 to 2.9 g with 120 pulses. 

Vessel venting 718Torr air removed 220 mg T in 1 h, but it took about 24 h to process the air. 2 g T was released in 4 months of air ventilation of the torus at the end of the DTE1 campaign. 

Remote tile exchange (RTE) not applied Divertor tiles, carriers and flakes have been physically removed in the RTE - 0.6 g T. 

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