Ex-situ tritium removal from JET tiles using RF inductive heating

Radio-frequency (RF) inductive heating has been successfully used as an ex-situ technique for the detritiation of entire tiles retrieved from JET. The assessment of the detritiation process used three different techniques, namely autoradiography, calorimetry and full combustion assisted by the liquid scintillation analysis. Autoradiography showed that using the RF technique more than 99% of the total surface tritium inventory can be efficiently removed from a tile after several heating cycles at the average temperature of only 490 deg. C. On the other hand, a comparison of the combustion measurements obtained before and after RF heating has shown that the bulk tritium activity decreased significantly (95% of the bulk tritium was released), while at the same time more than 99% of the surface tritium was liberated. The three methods used to assess the RF detritiation process have their advantages and disadvantages. Calorimetry allows a rough estimation of the tritium content of the complete tile, whilst IP imaging allows an approximate estimation of the content before and after detritiation but only for the surface tritium. On the other hand, full combustion associated with scintillation analysis allows very accurate measurements but only for specific samples with reduced dimensions, therefore extrapolation is needed to estimate the tritium content of an entire tile