ISOLATION COOLING SYSTEM OF NUCLEAR POWER PLANT

PROBLEM TO BE SOLVED: To provide an isolation cooling system of a nuclear power plant, which effectively utilizes heat energy of steam generated on the body side of a condenser to control heat removal of destruction heat caused by the isolation cooling system.SOLUTION: The isolation cooling system of the atomic power plant includes: an introduction pipe for introducing steam from a reactor pressure vessel; a condenser for heat-removing steam introduced from the reactor pressure vessel through the introduction pipe; a return pipe for returning condensed water condensed by heat removal in the condenser to the reactor pressure vessel; and an exhaust pipe for exhausting steam generated on the body side of the condenser by heat removal in the condenser. The isolation cooling system further includes: a flash tank for flashing and condensing the steam exhausted from the condenser through the exhaust pipe, in which a pressure control valve is attached to the exhaust pipe and pressure gauges are attached to the condenser and the reactor pressure vessel; and a pressure control device for controlling opening/closing of the pressure control valve based on measured values of steam pressures of the condenser and the reactor pressure vessel detected by the pressure gauges and a set value set by a pressure set unit.