Patent Number: 
Section: description

Referring now to the single FIGURE of the drawing in detail, there is shown a containment containing a base slab 1 and walls 2 which stand perpendicularly thereon. In the containment there is a reactor pressure vessel 8, from which, in an unlikely scenario, a nuclear melt could escape. To catch and cool a melt of this type, a porous body 3 is disposed on the base slab 1. For cooling purposes, numerous coolant lines 4, which may be branched, end directly at the porous body 3. The coolant is in this case water. It reaches the coolant lines 4 via a cooling channel 5 that leads from a coolant reservoir 9. If the reservoir 9 is at a sufficiently high level, a coolant pump is not required. The coolant penetrates into cavities of the porous body 3, where it can spread out in various directions without large accumulations of coolant being formed. If the hot melt subsequently comes into contact with the porous body 3, the melt is reliably cooled by the pre-pressurized coolant which enters it without there being any possibility of a dangerous steam explosion with all the attendant consequences. The melt is fragmented and generally stops above, but at the latest within the porous body 3. Then, as a result of the fragmentation, it has cavities into which the cooling water penetrates, resulting in further cooling until complete solidification has occurred. The porous body 3 is covered by a layer of sacrificial material 6. The sacrificial material 6 is melted when the melt comes into contact with it, and a mixture of the melt material and the sacrificial material 6 is formed. The sacrificial material 6 is selected in such a way that the mixture has a consistency and stratified configuration which are favorable for the fragmentation and therefore for the subsequent cooling. Moreover, the hot melt has already been cooled to some extent by contact with the sacrificial material 6. The sacrificial material 6 may be formed, for example, of a low-melting concrete, by which the melting point and density of the mixture are reduced. In the example shown, a sealing layer 7 of metal or plastic is disposed between the porous body 3 and the sacrificial material 6. This serves primarily to keep the coolant that is situated in the porous body 3 away from the sacrificial material 6 in the undisturbed state, so that the properties of this material remain unchanged. The coolant lines 4 generally end at an underside 3a of the porous body 3. This ensures a sufficient supply of coolant to the porous body 3. To ensure an even better supply, some coolant lines 4 may also end at side faces 3b of the porous body 3. With the device shown, a hot melt solidifies on the porous body 3 or at the very least before it can reach the base slab 1. This process prevents the hot melt from simultaneously coming into contact with large quantities of coolant. Consequently, there is no possibility of a steam explosion, which could cause attendant damage.