Transfer Phenomena of Tritium on Ceramic Breeder Materials

本文对不同锂陶瓷增殖材料的水捕获量进行了定量分析，并比较了包层中由于吸附而产生的氚存量与晶粒中扩散产生的氚存量。除非在高温包层中向吹扫气体中注入大量的H_2或H_2O，否则由于吸附而在包层处的氚库存要远远大于由于在晶粒中扩散而导致的氚库存。因此，可以认为从氚化水释放实验中得到的晶体中氚的扩散系数给出了包含表面传质阻力的值。本文还发现，在用氦扫气与氢同位素进行同位素交换实验的过程中，氧化锂床中水的形成是发生在同位素交换实验过程中。预计氚在繁殖毯循环中的行为在很大程度上受水的存在的影响。因此，了解在向包层吹扫气体中添加氢时发生的水形成现象是很重要的。

Present author has quantified the amount of water captured in various lithium ceramic breeder materials and compared the tritium inventory at the blanket due to sorption with that due to diffusion in the crystal grain. Tritium inventory at the blaket due to sorption is much larger than that due to diffusion in the crystal grain unless otherwise a large amount of swamping of H_2 or H_2O to the purge gas is applied in the high temperature blanket. Therefore, it can be considered that the diffusivity of tritium in the crystal grain obtained from the tritiated water release experiments gives the value including the mass transfer resistance at surface.It is also found by the present work that formation of water in the lithium oxide bed occurs in the course of the isotope exchange reaction experiments using He sweep gas with hydrogen isotopes.It is anticipated that behavior of tritium in the breeding blanket cycle is largely affected by existence of water. Accordingly, it is important to understand the water formation phenomenon occurs at addition of hydrogen to the blanket purge gas.