Partitioned crucible melt out-of-pile catcher

Abstract

The invention relates to a partitioned crucible melt out-of-pile catcher. The partitioned crucible melt out-of-pile catcher comprises a melt transferring channel, a melt collection crucible and a cooling water tank, wherein a refractory material is laid on the inner wall surface of the bottom part of a reactor pit; the melt transferring channel is connected with the reactor pit and the melt collection crucible, and also comprises a melt plug used for plugging the reactor pit; and the melt collection crucible is connected with the cooling water tank. The partitioned crucible melt out-of-pile catcher provided by the invention has the following beneficial effects: (1) through the specially-designed melt collection crucible, direct contact between an early-stage reactor core melt and cooling water is completely eradicated, so the risk of steam explosion is eliminated; (2) through introduction of a plurality of specially-designed cooling pipes, the heat exchange area of melts is increased,and the heat exchange capacity of the melts is further reinforced; and (3) through filling of the melt collection crucible with a sacrificial material, the melts are guaranteed to fully react with thesacrificial material before contacting with trap structural membranes (i.e., the cooling pipes and the wall surface of a container), so the temperature, melting point and volumetric power density ofthe melts are reduced.

Description

technical field [0001] The invention relates to the design technology of reactor safety system, in particular to an external catcher for zoned crucible molten matter. Background technique [0002] A severe accident at a nuclear power plant begins with a massive meltdown of the reactor's fuel assemblies, at which point the fuel cladding, the first barrier of defense in depth, has failed. If timely cooling cannot be obtained, the related internal components of the reactor will also be melted and form core melt, which will fall into the lower head of the reactor pressure vessel (RPV). In the case of insufficient external cooling of the RPV lower head, the RPV lower head will be melted, that is, the pressure boundary of the second barrier and the primary circuit is broken, and the core melt enters the containment vessel. After the pressure vessel melts through, the molten matter is directly sprayed onto the raft foundation of the containment to interact with the structural conc...

AI Technical Summary

Problems solved by technology

[0011] Regardless of the scheme of the deep water pool or the shallow water pool, there is a risk of steam explosion; the simple injection of water on the top of the molten material and submersion have a poor cooling effect on the molten material; the core catcher applied to EPR requires a large expansion chamber, and The melt migration path is long and there are many links; the problem of requiring a large layout space also exists in the core catcher scheme of ESBWR and EU-APR1400, while the relatively compact VVER1000 core catcher is arranged in the After melt retention is achieved, it takes at least 10 months for the melt to finally cool

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