After-heat removal system for FBR type reactors

Purpose: To conduct economical operation during normal state and remove after-heat reliably by way of a safety vessel when required. Constitution: The present invention concerns an after-heat removal system for FBR type reactors capable of removing after-heat through a safety vessel. When the nuclear reactor is in the operation state, the safety vessel is heated, and water in heat absorption tubes in close conduct with the outer surface of the safety vessel to formed into steams, which are sent from a steam drum to drive a turbine. Accordingly, almost of the heat energy dissipated from the vessel can be recovered to enable economical operation. While on the other hand, if the reactor operation is shutdown upon emergency, steams generated in the boiler are not supplied to the turbine but sent by way of a bypass pipe to a condensator and water formed by condensation is sent again through a liquid pipe to the boiler for recycling. Accordingly, after-heat upon reactor shutdown can rapidly be removed. (Kamimura, M.)