反应堆事故下安全壳地坑水池的化学效应

Chemical Effects in Containment Sump under Reactor Accident

核电站失水事故下,化学碎片可能引起安全壳地坑滤网堵塞,影响专设安全设施正常运行。模拟了不同材料遭遇喷淋冲刷进入安全壳地坑后的溶解、沉淀特性。结果表明:不同材料的溶解腐蚀有较大差异,同种材料在不同pH环境中也表现出腐蚀区别。Al、Si是产生化学沉淀的主要元素,启动安全壳喷淋系统和触发安全壳TSP(磷酸三钠)调节篮均能促进化学沉积生成,增加地坑滤网堵塞风险。降低Al、Si等元素释放是缓解滤网堵塞的重要措施。

Under the loss of coolant accident(LOCA)in a nuclear power plants,chemical debris may cause blockage of the sump strainer in the containment pool,and affect the normal operation of safety facilities.The dissolution and precipitation characteristics of different materials after LOCA were simulated.The results show that the corrosion of different materials was quite different,and the same material also showed differences in different pH environments.Al and Si were the main elements that produced chemical precipitation.Starting the containment spray system and triggering the containment TSP(Trisodium phosphate)baskets would promote chemical deposition and increase the risk of the sump strainer blockage.Reducing the release of Al and Si was an important measure to relieve the sump blockage.