Advancement of radioactive material removal system by silver zeolite (Quantitative evaluation of noble gas adsorption characteristics by XeA and construction of noble gas adsorption system)

In nuclear power plants, measures against radioactive noble gases are required. Until now, special activated carbon that easily adsorbs noble gases has been used in some nuclear facilities. However, activated carbon has a small adsorption capacity and is greatly affected by other gases and environmental humidity. Therefore, it is necessary to develop a new adsorbent with high adsorption performance. At emergency response stations, it is also necessary to take measures using air cylinders. It was confirmed that the newly developed silver zeolite XeA has more than 10 times adsorption efficiency of activated carbon for noble gas adsorption. In this paper, we will report on the basic noble gas adsorption performance of XeA and compare the adsorption performance between XeA and activated carbon. In addition, some applications of the noble gas adsorbent XeA are recommend, for example, (1) applied to noble gas countermeasures at emergency response stations, (2) applied to activated carbon noble gas hold-up systems, and (3) applied to emergency gas treatment systems (SGTS). Since silver zeolite XeA has excellent noble gas retention performance, it is possible to reduce the size and simplification of equipment by using it instead of the existing activated carbon. Furthermore, since XeA is nonflammable, it can be expected to improve safety.