Study on Tritium Release Behavior from Li₂ZrO₃

The present authors have developed the tritium release model to represent the tritium release behavior from solid breeder materials (Li₂ZrO₃, Li₂TiO₃, Li₄SiO₄, LiAlO₂ and Li₂O). It has been found that water is released from solid breeder materials into the purge gas due to desorption of physically and chemically adsorbed water and water generation reaction and that this water affects the tritium release behavior. In this study, the amount of adsorbed water and its desorption rate for Li₂ZrO₃ were quantified. It was found in this experiment that Li₂ZrO₃ has the largest adsorption amount among the solid breeder candidates. It was also observed that Li₂ZrO₃ has the largest water generation capacity among the solid breeder candidates. A unique reaction at around 550°C which made up approximately 80% of the capacity of water generation was also observed. It is considered that the phase change of ZrO₂ at around 550°C supplies oxygen to promote water generation reaction. Tritium release behavior from Li₂ZrO₃ blanket was estimated using the properties obtained in this study under the operational condition of ITER or a commercial reactor.