SERVICE INTERRUPTION EXHAUST APPARATUS

PURPOSE:To obtain a system capable of exhausting safely the remaining gaseous UF6 incorporated in the inside of a cascade even in such a case that a large- siized cooling collection apparatus is not provided to a main system by providing a vessel which is connected with a pipeline network and a pipeline and cooled with liquid N2. CONSTITUTION:A service interruption exhaust system unnecessitating an electric power source is constituted of a cryoexhaust system wherein a vessel cooled with liquid N2 is used. In other words, a cascade 1 is joined to a main system via the valves 2 in an ordinary operation period but connected to a service interruption exhaust apparatus 4 by closing automatically the valves 2 and opening a valve 3 in a loss period of an electric power source. On the other hand, since liquid N2 is ordinarily stored in a tank and press-sent with the pressure in the tank and the liquid feed is enabled even in case of the service interruption, the cooling of the service interruption exhaust apparatus 4 can be maintained. In this state, gaseous UF6 remaining in the inside of a cascade 1 can be cryo-exhausted to the service interruption exhaust apparatus 4.