EMERGENCY REACTOR CORE COOLING BACKUP SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an emergency reactor core cooling backup system capable of effectively using high-pressure water supplied from a control rod drive water pump (CRD pump) for system elements of an emergency core cooling system (ECCS) without the need to connect a new independent pipe to a nuclear core pressure vessel itself.SOLUTION: A backup water supply line BL 1 serves as bypasses between a downstream side of a CRD pump 14 on a drive water line L1 related to driving of a control rod and a downstream side of an aqueous boric acid supply pump 21 on an aqueous boric acid supply line L2, and a valve V3 is opened as needed so as to supply high-pressure drive water from a water source (condensed water storage tank) CST to the aqueous boric acid supply line L2 via the CRD pump 14 as cooling water, thereby making it possible to supply water to a lower portion of a nuclear reactor pressure vessel 10.