Development of a tritium release system for ceramic tritium breeder pebbles irradiated by high intensity DT fusion neutron Generator at INEST

For ceramic breeder pebbles used in fusion energy, the tritium release data under fusion neutron irradiation is very important and valuable. In this study, a tritium release system for ceramic tritium breeder is introduced, which is matched with the High Intensity DT Fusion Neutron Generator (HINEG-CAS). The HINEG-CAS has been built and operated by the Institute of Nuclear Energy Safety Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences (INEST, HFIPS, CAS), achieving a fusion neutron yield of 1012n/s since 2016. Innovative design and fabrication of sample container enables minimization of the unexpected tritium loss. The dedicated tritium release system can monitor the tritium release behavior over time for both tritiated water and tritium gas, using the bubblers-based tritium trapping system with automatic replacement technology, coupled with highly efficient catalytic oxidants and liquid scintillation counter (LSC). We have performed a tritium release experiment with the Li2TiO3 pebbles as ceramic tritium breeder, and obtained the tritium releasing data at room temperature over time and clarified the tritium chemical form in recovery. It is concluded that this newly established system can serve as a good sharing platform for evaluating prime candidate breeder materials, as well as facilitating detailed design or optimization of tritium involved systems (such as the tritium extraction system).