Nuclear reactor equipped with a device for recovering the core after its accidental meltdown

摘要

In order to recover and confine the core of a nuclear reactor such as a pressurised water nuclear reactor, in the event of a serious accident leading to its meltdown, it is proposed to place, above the vessel (16) of the reactor, a receptacle (20) capable of removing the water accumulated below the vessel (16) in the initial phase of the accident and, in a second stage, to collect the debris of the melted core. The water flows automatically through devices with overspills and siphons (46, 50) into a cooling space (40) located below the receptacle. If meltdown of the core (18) is detected, the water contained in tanks (56) flows under gravity into the space (40), so as completely to immerse containers (26) placed in this space. The melted core passing through the bottom of the vessel (16) flows into the receptacle (20) then into the containers (26) through fusible plugs (32) and a natural convection circulation is established between the tanks (56) and the space (40) in order to provide the cooling. Drop shock absorbers (76) are placed in the receptacle (20) in case the bottom of the vessel (16) should fall as a single block. IMAGE