APPARATUS AND METHOD FOR CORRECTING INJECTION OF LOW-PRESSURE COOLING MATERIAL FOR BOILING WATER REACTOR

摘要

PURPOSE: To obtain a safety device which responds to a failure by injecting a necessary amount of coolant into a circulating loop for a necessary period of time by actuating a low-pressure coolant injecting(LPCI) pump and opening injection valves in both LPCI areas when a loss of coolant accident happens. CONSTITUTION: When a state of emergency requiring suppression pool cooling occurs due to an accident, valves 91a and 91a supply a heat exchange loop function by means of a shut-off valve 108a and a fluid by-pass to a heat exchanger 114a from a suppression pool 84 and header 86. The fluid flows to a conduit 126a through an opened LPCI valve 120a. Then an LPCI valve 124a is closed so as to branch the cooling fluid to the pool 84. When a high- pressure state occurs in a containment, the pressure boundary of a containment mechanism is protected by using quenching or spraying. A cross-tie valve 172a is left opened and an orifice combination 118a cools a reactor core 80 while the recirdulating time and quantity of a water coolant are limited by means of an independent recirculating loop 56.