Safety feed for borating system for a pressurized water reactor and

Abstract

In the event of an incident in a pressurized water reactor with a safety feed and borating system, it is necessary that sufficient primary cooling water be available in the reactor cooling system or be resupplied, and it must also be possible to render the reactor subcritical with added boron and to maintain it in that state. The invention is a safety feed and borating system for a pressurized water reactor with series-connected safety feed and additional borating pumps. The additional borating pump is connected downstream of the safety feed pump and it has a parallel-connected bypass line with a check valve. Both pumps have a common minimum quantity line with different and reversible throttle restrictions. Thus the feed level and throughput of the entire system can be adapted optimally to existing demands. It is no longer necessary to provide a separate high-pressure borating system. The method of operating the safety feed and borating system allows control over four different abnormal operating states of the pressurized water reactor.