Mitigation of steam generator tube rupture in a pressurized water reactor with passive safety systems

摘要

The effects of steam generator tube (21) ruptures in a pressurized water reactor (1) are mitigated by reducing the pressure in the primary loop by diverting reactor coolant through the heat exchanger (37) of a passive heat removal system immersed in the in containment refueling water storage tank (35) in response to a high feed water level in the steam generator (11). Reactor coolant inventory is maintained by also in response to high steam generator level introducing coolant into the primary loop from core make-up tanks (43) at the pressure in the reactor coolant system pressurizer (31). The high steam generator level is also used to isolate the start-up feed water system (81) and the chemical and volume control system (85) to prevent flooding into the steam header (27).