DE102017108423B4 - METHOD FOR CREATING A SAFE INCLUSION OF AN ATOMIC POWER PLANT, A NUCLEAR PLANT OR AN INTERMEDIATE STORAGE PLANT - Google Patents

Abstract

It is a method for creating a secure enclosure of a disused nuclear power plant or an intermediate deposit disclosed, wherein the filled with air or water building voids of the decommissioned nuclear power plant or cavities of the intermediate storage is filled with polyurethane foam.

Description

Nuclear power plants (nuclear installations), after their decommissioning, can usually be directly dismantled, transferred to a safe containment or transferred to a safe enclosure for a limited period of time and dismantled after the limited period of time. In the case of safe enclosure, the nuclear power plant is separated from the biosphere by means of a concrete shell.

Both the immediate and later dismantling is associated with high costs and leaves due to the radiation exposure but a long-term unusable terrain. The permanent safe enclosure by means of concrete sheath requires permanent maintenance and repair work of the concrete structure.

It is therefore an object of the invention to provide an improved method for creating a secure enclosure that is more cost effective and associated with less maintenance and servicing.

According to the invention the object is achieved with the features of claim 1.

More particularly, the object is achieved by a method for creating a secure enclosure of a disused nuclear power plant, a nuclear facility or an intermediate storage facility, wherein the filled with air or water building cavities of the decommissioned nuclear power plant or nuclear facility or cavities of the intermediate storage with polyurethane foam, preferably well foam, be filled.

This procedure completely fills the building cavities of a decommissioned nuclear power plant so that the equipment inside it is sealed. Therefore, the systems are not exposed to external influences and do not rot. In intermediate storage facilities, the cavities are completely filled so that the components of former nuclear power plants stored therein are sealed.

Preferably, the building cavities include all cavities in lines, cooling towers, shafts and in the reactor building itself.

Preferably, the filling of the building cavities takes place from below, so that water or air in the building or in the intermediate storage site is safely displaced. The filling material (polyurethane foam, preferably fountain foam) can thereby be selectively introduced into the building cavities, so that it is ensured that no unwanted cavities remain. If, for example, there is water in the building or the intermediate storage, the filling material can be introduced under water, so that the water is displaced by introducing the filling material. As a result, the water does not have to be pumped out.

Preferably, in nuclear power plants before filling the cavities with polyurethane foam, the fuel rods are removed and the cooling water is pumped out.

In addition, filling the cavities of the nuclear power plant building creates a monolithic block, which also changes the static structure of the nuclear power plant building. As a result, higher loads can be applied to walls and roofs that were previously designed only for the usual loads. This makes it possible in turn to cover the filled nuclear power plant with debris (preferably gravel and concrete debris, but no organic matter) and thus to build a rubble mountain on it. Such a pile of rubble can be permanently created, so that a decommissioning of the nuclear power plant is not required. As a result, the dismantling costs can be completely saved. In addition, it is not necessary to build a structurally more demanding concrete shell, which further costs can be saved.

Preferably, the pile of debris is sealed after erection with a clay layer. The clay layer preferably has a thickness of about 20 cm and serves to seal the pile of debris.

Preferably, the clay layer is covered with cement mats. These cement mats are preferably cement-enriched mats that can be easily laid. The cement does not bind off until it comes into contact with water. The water gets the cement from the underlying clay layer and from rainwater during a rain event. The hardened cement mats seal the pile of debris in addition to the clay layer.

Preferably, the cement mats are coated with a humus layer. This humus layer can be planted in a suitable way, so that the vegetation by the action of its roots stabilizes the humus layer. Preferably, the humus layer has a thickness of 20 cm.

Alternatively, a mastic asphalt layer may be introduced between the cement mats and the humus layer. As a result, even more secure sealing of the pile of rubble can be achieved.

Preferably, the polyurethane foam is a so-called well foam, which is intended for use in civil engineering at permanently moist locations.

• 1 eine schematische Ansicht eines Atomkraftwerks zur Veranschaulichung eines ersten und eines zweiten Verfahrensschritts;
• 2 eine schematische Ansicht des Atomkraftwerks zur Veranschaulichung eines dritten Verfahrensschritts;
• 3 eine schematische Ansicht des Atomkraftwerks zur Veranschaulichung eines vierten Verfahrensschritts;
• 4 eine schematische Ansicht des Atomkraftwerks zur Veranschaulichung eines fünften Verfahrensschritts;
• 5 eine schematische Ansicht des Atomkraftwerks zur Veranschaulichung eines sechsten Verfahrensschritts;

Now, an embodiment of the invention will be described with reference to figures. In the figures:

• 1 a schematic view of a nuclear power plant for illustrating a first and a second method step;
• 2 a schematic view of the nuclear power plant to illustrate a third method step;
• 3 a schematic view of the nuclear power plant to illustrate a fourth process step;
• 4 a schematic view of the nuclear power plant to illustrate a fifth method step;
• 5 a schematic view of the nuclear power plant to illustrate a sixth method step;

In the embodiment of the invention, a nuclear power plant 1 as it is in 1 is shown, first shut down and the fuel rods are removed and the cooling water is pumped out. There will also be a chimney 3 of the nuclear power plant 1 dismantled and a cooling tower 2 is at least partially dismantled, as indicated by the dashed lines in 1 is indicated. The aim of this disassembly is to reduce the overall height of the nuclear power plant by simple means. As a guideline, the building height of the power plant except the cooling tower is used here.

After the preparatory dismantling work, the building cavities of the decommissioned nuclear power plant filled with water and / or air are then sealed from below with fountain foam. In any case, it is important that the fountain foam is introduced in such a way that it displaces the air and water that still remain in the building cavities. This ensures that the cavities are completely sealed and the building and existing installations are protected against corrosion and weathering. In addition, the static load-bearing capacity of the building structure is increased by the backfilling, so that the loads of the later landfills can be safely removed.

It is also possible to fill only building cavities with fountain foam in which there are still corrosion-prone facilities, and to fill the remaining building cavities with gravel and / or rubble.

As in 2 can be seen, then a rubble mountain 4 erected above the backfilled building structure. The used debris penetrates into the areas between the individual parts of the building. The height of the rubble mountain depends on the height of the remaining parts of the building. All remaining parts of the building should be completely covered. As suitable materials, for example gravel and / or concrete debris can be used. However, no organic material may be used.

3 shows that the finished Schuttberg 4 with a clay layer 5 is sealed. The clay layer is at least 20 cm thick.

After building the clay layer, this is done with cement mats 6 covered, as in 4 is shown. In addition, the application of mastic asphalt is possible in order to better seal the pile of rubble overall.

5 finally shows that with clay 5 and cement mats 6 sealed rubble mountain 4 with a humus layer 7 is covered, which is then greened.

Thus, it is possible according to the invention to produce a safe enclosure of buildings which is more cost-effective than a complete demolition of the nuclear power plant.

Claims (7)

A method for creating a secure enclosure of a disused nuclear power plant, a decommissioned nuclear facility or an intermediate storage facility, wherein the filled with air or water building cavities of the decommissioned nuclear power plant or cavities of the intermediate storage with polyurethane foam, preferably fountain foam filled. Method according to Claim 1 , wherein the filling of the building cavities or the cavities of the intermediate deposit takes place from below, so that the water and / or the air are safely displaced. Method according to Claim 1 or 2 , whereby on the disused and filled nuclear power plant or the intermediate deposit a rubble mountain is established. Method according to Claim 3 , wherein after the construction of the rubble mountain this is sealed with a clay layer. Method according to Claim 4 wherein the clay layer is covered with cement mats. Method according to Claim 5 wherein the cement mats are coated with a mastic asphalt coating. Method according to Claim 5 or 6 in which the cement mats or the mastic asphalt coating are coated with a humus layer.

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