Tritium Removal from JET and TFTR Tiles by a Scanning Laser
Authors: C.H. Skinner, N. Bekris, J.P. Coad, C.A. Gentile, and M. Glugla
Date of PPPL Report: May 2002
Presented at: the 15th International Conference on Plasma Surface Interactions in Controlled Fusion Devices (PSI-15) (Gifu, Japan, May 27-31, 2002). Conference proceedings to be published by the Journal of Nuclear Materials.
Fast and efficient tritium removal is needed for future D-T machines with carbon plasma-facing components. A novel method for tritium release has been demonstrated on co-deposited layers on tiles retrieved from the Tokamak Fusion Test Reactor (TFTR) and from the Joint European Torus (JET). A scanning continuous wave neodymium laser beam was focused to approximately 100 W/mm2 and scanned at high speed over the co-deposits, heating them to temperatures approximately 2000 degrees C for about 10 ms in either air or argon atmospheres. Fiber optic coupling between the laser and scanner was implemented. Up to 87% of the co-deposited tritium was thermally desorbed from the JET and TFTR samples. This technique appears to be a promising in-situ method for tritium removal in a next-step D-T device as it avoids oxidation, the associated de-conditioning of the plasma facing surfaces, and the expense of processing large quantities of tritium oxide.