Residual Tritium Amount Estimation in the Components and Pipes of Lithium Target System for A-FNS After Its Operation

It is necessary for the determination of the design requirements of the detritiation system for the A-FNS to estimate the residual tritium amount in the components and pipes of the lithium target system for the A-FNS, where tritium would exist in residual lithium on the surface and dissolve in the structural materials. The residual lithium amount in each of the components and pipes of the Engineering Validation and Engineering Design Activities (EVEDA) Lithium Test Loop was measured to estimate that amount for the A-FNS, and the dissolved tritium amount in each of them was calculated numerically. As a result, the maximum tritium amounts for the residual lithium and that dissolved in the structural material for one component of the A-FNS were estimated as approximately 80 TBq and 2 GBq, respectively. It was also found that a hydrogen trap is necessary to decrease the concentration of the tritium dissolved in the materials below the clearance level.