Patent Number: 053496159
Section: abstract

The device (4) for the retention of core melt-through in light-water reactors by means of a crucible (40) disposed beneath the reactor pressure vessel (2) comprising of a vat (41) and a plurality of sack-like protuberances (42) on its underside and also of a metal lid (43). The lid forms a water-tight upper seal for the crucible and has a reinforcement (43b) to absorb the kinetic energy of the impact of the core melt-through. The crucible consists of a metal wall (40a), which is lined with a ceramic material (40b)--preferably made from high-temperature isostatic pressed boron nitride. The device (4) is disposed in a water-filled cooling basin (32), which forms the lowest part of the containment sump and which can be constructed as a cavity in the containment foundation. The water vaporized during cooling if the requirements are met condenses on the walls of the containment and flows back into the containment sump.