Development of the cover gas clean-up system for experimental fast reactor 'JOYO'

In Experimental Fast Reactor JOYO, the RTCB (Run To Cladding Breach) test has been planning in the part of fast reactor fuel development. In the test, FP (Fission Product) is released to the primary cooling system, and a most of novel FP gas such as Xe, Kr moves to argon cover gas in the reactor vessel. The CGCS (Cover Gas Clean-up System) employing cryogenic adsorption method is developed to condense FP was with high efficiency and to reduce the load of gaseous waste treatment disposal system. In the development of CGCS, it is important that to prevent circulation flow blockade of reactor cover gas with liquid argon, to reduce employment quantity of liquid nitrogen and to extend operating time. These problem were solved by mixing of liquid nitrogen with nitrogen gas and by improvement of the pressure control method. As a result of this study, high efficiency is achieved by extention of operating time. (author)