RU2461U1 - Spent Nuclear Fuel Storage - Google Patents

Abstract

1. A storage facility for spent nuclear fuel, including a water basin, a slotted beam ceiling, canisters with spent nuclear fuel, located on the beams of the slotted ceiling, characterized in that the canisters are filled with chemically inert gas with a pressure exceeding the static pressure of the water column of the pool. The storage facility according to claim 1, characterized in that radiation protective means are placed in the cavities of the canisters above the spent nuclear fuel.

Description

STORAGE OF WASTE ONE FUEL.

The utility model relates to nuclear engineering, in particular, to spent nuclear fuel storage facilities having slotted beam ceilings and can be used at nuclear power plants.

The type of storage facility, in which canisters with spent nuclear fuel are located only in the inter-beam space is described in the work: K.A. Ostryanin et al., - Storage of spent fuel at nuclear power plants, in the collection of materials of the fifth symposium of the CMEA member countries, Czechoslovakia, Marianske Lazne , April I98I. Research in the field of generalized fuel processing and waste neutralization, p. 14-12.

The closest analogue of the claimed technical solution is the storage described in c. in the aforementioned collection. The storage facility consists of a water basin, a slit girder floor, canisters with spent nuclear fuel (SNF) placed directly on the beams by means of flanges.

The disadvantages of the technical solution for the closest analogue is that the water from the canisters during storage evaporates under the influence of residual heat. To restore the level, topping up water is required. As a result, impurities accumulate in the canisters (halogen1ra1), the formation of nitrates of radiolytic origin occurs, and their concentration becomes stagnant R. The above leads to the development of corrosion processes of structural materials of fuel assemblies and canisters. As a result, the storage on QUQ. safe conditions

storage since corrosion of the material of the fuel assemblies leads to their depressurization, and corrosion of the canisters leads to the leakage of highly active water from the canister into the pool.

The problem solved by this technical solution is to eliminate the noted deficiencies.

The essence of the proposed technical solution consists in the fact that in the spent nuclear fuel storage facility including a water pool, slotted beam overlap, spent nuclear fuel canisters placed on slotted beams, the canisters are filled with chemically inert gas with a pressure exceeding the static pressure of the pool water column, and over fuel assemblies in canisters placed radiation protective equipment. The use of chemically inert gas instead of water in canisters will protect fuel assemblies and canisters from corrosion damage and increase the environmental safety of the storage facility. As a chemically inert gas, for example, L or another known gas can be used. The gas pressure in the canister is set to the pressure of the pool water, in order to prevent water from entering the canister when it is depressurized. I use radiation protection means 1 xg 1 yaayaaaSh1PYaP © "ionizing radiation of fuel assemblies. A protective cork made of radiation absorbing material, for example, metal, concrete, and other known material, can be used as a radiation protective agent installed in a pencil case.

The technical solution is illustrated by drawings. FIG. Figures 1, 2 and 3 show fragments of SNF storage options.

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H - Fig. 4 shows a case with a PC. Figs. 5 and 6 show sealing options for a canister cover. Fig. 7 option to install spent fuel in a pencil case.

SNF storage (Fig. 1) consists of a water basin I, a bottom 2, slit beams 3, suspensions 4, canisters 5 with covers 6, datac tanks 7 for monitoring gas parameters in canister 5. Fig. 2, 3 shows a variant of storage SHT, containing a collector 8 for supplying chemically inert gas to the cavity of the canisters 5. Case 5 (Figs. 4,5,6) contains a housing 9, with a sealed lid 10, and a fitting II for supplying gas and connecting sensors 7 for monitoring gas parameters. Inside the canister 5 there is a fuel assembly (SNF) 12 with a transport liner 13 on which protective equipment is placed (plug ) 14, On (figure 5) shows a variant of sealing the lid Yu on the pencil case 5 by means of a sealing connection. On Fig.6) shows a variant of sealing krevpki 10 on the pencil case 5 by means of a weld seam 15. On (Fig.7) shows a variant of the installation of protective means (plugs) 14 on the shank 13 of the fuel assembly 12 through the connecting element 16.

The storage is used as follows (Fig. 1,7). The fuel assembly 12 is installed in the case 5 with a protective agent (stopper) 14. The case 5 is sealed with a cap Yu, chemically inert gas is supplied through the nozzle II to the cavity of the case 5 and the pressure sensor 7 is connected. By means of suspension 4, case 5 is installed by a vehicle (not shown in FIG.) Into the water volume of basin I. Therefore, suspension 4 is placed on the beams 3 of the slotted floor. According to the sensor 7 pressure-2, the pressure is checked for the tightness of the case during storage of SNF. measures to restore the gas pressure in the canister 5. In the embodiment shown in FIG. 2, the gas supply manifold 8 is constantly connected to the cavities of the canisters; in the event of depressurization in any of the canisters 5, the gas pressure will be maintained at a predetermined level, which eliminates the ingress of water into the pencil case 5. The presence of gas in the cavity of the pencil case 5 can be controlled by any other known devices.

The implementation of the utility model will increase the zcological safety of the storage of the CT.

- 4 FORMULAS

Claims (2)

1. A spent nuclear fuel storage facility including a water basin, a slit girder floor, spent nuclear fuel canisters placed on slit girder beams, characterized in that the canisters are filled with chemically inert gas with a pressure exceeding the static pressure of the pool water column.  2. The storage facility according to claim 1, characterized in that radiation protective equipment is placed in the cavity of the canisters above the spent nuclear fuel.