Detritiation of JET tiles by laser cleaning

The retention of tritium (T) by carbon based deposits on tokamak surfaces is of increasing concern to the fusion community as the scale of tritium retention by this mechanism could be a limiting factor for the operation of fusion reactors, such as ITER. Hence there is a need to investigate ways of mitigating T retention and also for detritiating surfaces by either desorption of T or removal of tritiated deposits. The results of the removal of codeposits from CFC tiles by pulsed laser ablation are reported here. The results show that it is possible to completely remove a 300μm thick hydrogen isotope rich carbon film at a rate of 12x10-3m2/hr by this method and that with optimisation of the laser parameters there is scope to improve the treatment rates to provide a useful tool for managing T inventory in tokamaks