Application of a Hydrothermal Treatment for the Decontamination from Tritium of Fusion Reactor Materials - Tritium Decontamination Using an Autoclave

A batch process concept for the decontamination from tritium of fusion reactor materials based on a hydrothermal treatment is under development at HRC. Essentially, tritium-loaded material is heated in a tightly closed vessel containing a defined amount of water. The objective of the water is to “capture” the released tritium in a small volume of liquid. For the detritiation, stainless steel temperatures in the range 393-473 K over a period of several days were found to be adequate. From the results it appears that by and large the released tritium accumulates in the purposely introduced water. The achieved degree of decontamination was estimated from the tritium concentration in the water and the tritium that remained in the decontaminated material. Tritium trapped in the surface layer of stainless steel was not reduced by the isochoric hydrothermal treatment in the same proportion as that in the bulk.