Chemical Effects in Containment Sump under Reactor Accident

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.