FEEDING METHOD OF EMERGENCY CORE COOLANT SYSTEM OF PRESSURIZED WATER REACTOR

摘要

PURPOSE:To provide a feeding method of emergency core coolant system with respect to the piping break accident of pressurized water reactor enabling the effective core cooling to perform. CONSTITUTION:Now, when a break B is occurred at low temperature pipe which joins the circulation pump 3 connected with the steam generator 2 and the pressure vessel 1, the pressure and temperature of the primary system of the reactor are lowered. When the pressure is lowered below set pressure of 50-90 atg of the pressure accumulating feed system, the check valve 51 is opened automatically causing the coolant of the pressure accumulating feed system 41 to enter into the top plenum 6. The temperature of the coolant is set at comparatively high temperature of 80-200 deg.C, which causes low condensing capacity even the steam is generated in the top plenum 6. The suction of water remained in the core 7 is suppressed, which allows to continue cooling. When the pressure is further lowered, causing to lower below the set pressure pressure of 25-60 atg of pressure accumulating feed system 42, the check valve 52 is opened allowing the coolant to deliver to the bottom plenum.