In-pile melts retention system after nuclear power station accident

The invention belongs to a reactor design technology, and concretely relates to an in-pile melts retention system after nuclear power station accident. A structure of the in-pile melts retention system comprises a pressure vessel placed in a pile, an IVR working medium high container is arranged at the position of the pile higher than the pressure vessel, the IVR working medium high container is connected to the pile through an injection line, a heat exchanger is arranged in a space between the pressure vessel in the pile and the exterior wall of the pile, the heat exchanger is connected to a displacement material water tank in the reactor through a circulation pipeline, and the IVR working medium employed by the system is metal gallium. The in-pile melts retention system can effectively avoid the risk of ebullition of the exterior wall of the pressure vessel, so that the system can ensure that a pile core can not melt through the exterior wall of the pressure vessel.