Speaker
Yasunori Iwai
(Department of Blanket Systems Research)
Description
Effect of halogenated gas on detritiation efficiency of the detritiation system was investigated. In order to accelerate tritium safety of the Japanese DEMO reactor, the detritiation system should be designed taking possible off normal events such as fire carefully into consideration. In an event of fire in a tritium processing room, halogenated gases such as hydrogen chloride, halogenated hydrocarbons and chlorine would be produced from the burning of the electric cables which insulation is made from polyvinyl chloride. In the presence of these gases, the detritiation system which key components are the catalytic reactor for the oxidation of tritium in combination with following tritiated vapor absorber should not lose their conversion and detritiation efficiencies. Concerning the activity of platinum catalyst for the oxidation of tritium, we evaluated the decrease in activity of platinum catalyst in the presence of halogenated gases. In order to avoid the steep decrease in activity, a noble catalyst alloyed with platinum and palladium showed an outstanding proof against halogenated gases. Turning to the effect of tritiated reactions in the catalytic reactor on conversion efficiency, formation of tritium chloride by the reaction between tritium and chlorine had an impact on conversion efficiency at temperature of catalyst below 373 K. As for water absorber, a molecular sieve moderately decreased its water absorbing capacity especially in the presence of chlorine. The results of this study reveal that the selection of catalyst is the key to preserve the detritiation efficiency of the detritiation system in the presence of halogenated gases.
Co-authors
Akiko Kondo
(Department of Blanket Systems Research, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan)
Katsumi Sato
(Department of Blanket Systems Research, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan)
Yasunori Iwai
(Department of Blanket Systems Research, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan)
Yuki Edao
(Department of Blanket Systems Research, Japan Atomic Energy Agency, Tokai, Ibaraki, Japan)
