JP2000056071A - Spent fuel storage module, auxiliary block and spent fuel storage facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide spent fuel storage modules capable of arranging many spent fuel storage canisters in the horizontal and vertical directions to store them on a small site and capable of efficiently discharging the heat of spent fuels. SOLUTION: A module 3 horizontally storing a canister 2 sealed with a spent fuel in it is stackably formed into a protruded shape at the upper section and a recessed shape at the lower section. A canister cooling air passage 6 communicated with a storage chamber in the module 3 is formed in the vertical direction, both side walls are formed into shielding walls 7, the inlets of the canister cooling air passage 6 are laterally opened on both the right and left inside faces of the recessed lower section, and the outlets are laterally opened on both the right and left outside faces of the protruded upper section. When the spent fuel storage modules 3 are stacked, the inlets and outlets are communicated with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a module for storing spent fuel of a nuclear power plant, an auxiliary block, and a spent fuel storage facility.

[0002]

2. Description of the Related Art As a conventional spent fuel storage facility of this kind, Japanese Patent No. 2502121 (registered March 1996
13) is a horizontal modular spent fuel storage system. The horizontal storage module in this system
As shown in FIG. 13, the I-shaped steel 7 embedded in the housing 68 provided on the support base 70 is basically in a block shape.
4 supports the spent fuel storage canister 112 inserted from the port 76 into the housing 68. The port 76 is provided with a shutter door 80 that can be lifted upward. Horizontal storage modules include:
The air-cooling system 82 has a plurality of ports disposed below the port 76, and the ports of the air-cooling system 82 are connected to a ventilation chamber 86 via a cooling air flow path 88 of a bypass pipe. The air in the ventilation chamber 86 is transferred to the cylindrical passage 9.
2 surrounding the canister 11 and arranged inside the canister 11
2 to remove the decay heat of the stored spent fuel, and the resulting hot air is supplied to cooling air passages 90 and 9 connected to exhaust manifolds 94 and 96.
2 through which the air is exhausted through exhaust ducts 98 and 100. Staggered connecting portions 102 and 104 are provided at the upper ends of both sides of the housing 68 so that when the housings 68 are adjacent to each other, they are overlapped and connected.

Since the horizontal storage module is presumed to be additionally installed only in the horizontal direction, a large site is required to store a large number of spent fuel storage canisters, and a site for storing spent fuel is required. Use efficiency was poor.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to make it possible to arrange a large number of spent fuel storage canisters not only in a horizontal direction but also in a vertical direction so that they can be stored on a small site, and to efficiently remove spent fuel. An object of the present invention is to provide a spent fuel storage module and an auxiliary block which can be heated and a spent fuel storage facility including them as basic components.

[0005]

According to a first aspect of the present invention, there is provided a spent fuel storage module according to the present invention, wherein a module for horizontally storing a canister in which spent fuel is sealed is provided with an upwardly projecting stackable stack. A canister cooling air passage is formed in the vertical direction, communicating with the storage chamber in the module, is formed in a vertical direction, and both side walls are formed as shielding walls, and an inlet of the canister cooling air passage is formed in a concave lower portion. The opening is opened laterally on both left and right inner surfaces, and the outlet is opened laterally on both left and right outer surfaces of the convex upper portion, so that the inlet and the outlet communicate when the modules are stacked.

[0006] One of the spent fuel storage facilities of the present invention is one in which the spent fuel storage modules are installed continuously in the lateral direction.

The auxiliary block according to the present invention is a short block installed on an upper surface of the spent fuel storage module, wherein the block is formed in an upper concave shape and a lower concave shape,
Cooling air passages are formed on both sides in the vertical direction, the inlet is opened laterally on both left and right inner surfaces of the concave lower part, and the outlet is opened laterally on the left and right inner surfaces of the concave upper part. It is assumed that.

Another one of the spent fuel storage facilities of the present invention is such that the auxiliary blocks are stacked on an upper surface of each spent fuel storage module of the spent fuel storage facility, respectively, and a convex upper portion of each module is provided. And an outlet of the canister cooling air passage and an inlet of the cooling air passage of the auxiliary block are connected to each other.

[0009] Still another one of the spent fuel storage facilities of the present invention is that the same module is stacked in one or two stages on the upper surface of each spent fuel storage module of the spent fuel storage facility, and a lower module is provided. The concave lower part of the upper module is fitted to the convex upper part of the upper part, and the outlet and the inlet of the canister cooling air passage are connected to each other.

[0010] Still another one of the spent fuel storage facilities of the present invention is arranged adjacent to a longitudinal direction of each spent fuel storage module of any one of the spent fuel storage facilities. The module and the auxiliary block are arranged back to back in the same arrangement.

[0011] Still another one of the spent fuel storage facilities of the present invention is that the entire spent fuel storage module or the spent fuel storage module and the auxiliary block in which a large number of the above spent fuel storage facilities are arranged. It is characterized by being covered with a large earthquake-resistant wall.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a spent fuel storage module according to the present invention will be described with reference to FIG. 1. A concrete module 3 for horizontally storing one canister 2 in which spent fuel is sealed is stacked. If possible, the upper part 4 is convex and the lower part 5 is concave. Inside each module 3, canister cooling air passages 6 for cooling the canister 2 in the vertical direction are formed on the left and right sides, the entire side walls 7 are formed as shielding walls, and the inlet 8 of the canister cooling air passage 6 has a concave lower portion 5. Is opened laterally on both left and right inner surfaces of
Are opened laterally on both left and right outer surfaces of the convex upper part 4 so that the entrance 8 and the exit 9 communicate with each other when the modules 3 are stacked. The canister cooling air passage 6 is communicated in the middle with a storage room 10 that stores the canister 2 horizontally, and one or two liners 11 for heat shielding both side walls 7 are disposed on both left and right sides in the storage room 10. ing. Reference numeral 12 denotes a shielding door that closes a loading / unloading port 13 for taking in and out the canister 2 in the storage room 10.

In the spent fuel storage module 3 configured as described above, the naturally ventilated cooling air that has entered through the inlets 8 on the left and right inner surfaces of the concave lower portion 5 bends by 90 degrees to form the canister cooling air passage 6. Rises into the storage room 10 to cool the canister 2 and remove heat generated by the spent fuel sealed in the canister 2, and the resulting hot air is cooled from the storage room 10. The air passage 6 rises, bends at the upper end, and exits 9 on the left and right outer surfaces of the convex upper part 4.
It is exhausted from. This cooling air flows through the canister cooling air passage 6 in the vertical direction, so that the cooling air can flow uniformly over the entire length of the canister with little resistance and no stagnant flow. Is high. Therefore, the spent fuel storage module 3 is suitable for initial storage having a high calorific value.

One embodiment of the spent fuel storage facility of the present invention is shown in FIG. In this spent fuel storage facility 1, the spent fuel storage modules 3 are arranged continuously in the lateral direction, and each spent fuel storage facility 1 has high heat removal efficiency as described above. Therefore, it is effective for the initial storage of spent fuel having a high calorific value.

FIG. 3 shows an embodiment of the auxiliary block according to the present invention. The auxiliary block 21 is a short block installed on the upper surface of the spent fuel storage module 3, and has an upper portion 16 formed in a concave shape and a lower portion 17 formed in a concave shape. 18 are formed in the vertical direction,
An inlet 19 of the cooling air passage 18 is opened laterally on both left and right inner surfaces of the concave lower part 17, and an outlet 20 is formed in the concave upper part 16.
Are opened laterally on the left and right inner surfaces.

Another embodiment of the spent fuel storage facility of the present invention is shown in FIG. This spent fuel storage facility 15
The auxiliary block 21 of FIG. 3 is stacked on the upper surface of each spent fuel storage module 3 of the spent fuel storage facility 1 of FIG. The lower part 17 is fitted, and the outlet 9 of the canister cooling air passage 6 and the inlet 19 of the cooling air passage 18 of the auxiliary block 21 are connected as shown in FIG.

The spent fuel storage facility 15 configured as described above can be used when the heat generated by the spent fuel sealed in the canister 2 stored in the storage room 10 of each module 3 is very large. Effective heat removal. That is, when the auxiliary blocks 21 are stacked on the upper surface of each module 3, the height of the cooling air passages 6 and 18 as a whole increases, the cooling capacity is improved by the chimney effect, and the flow velocity is slow. The generated heat of the spent fuel is sufficiently removed. However, as shown in FIG. 6, in the spent fuel, the calorific value (decay heat) attenuates with the passage of the cooling years (storage time). The height with the auxiliary block 21 becomes excessive at the time when the calorific value is attenuated. Therefore, the auxiliary block 21 is removed to cope with the attenuation of the calorific value, and the spent fuel storage facility 15 is reduced to the spent fuel storage facility 1 shown in FIG.

In the spent fuel storage facility 22 shown in FIG. 7, the same module 3 is stacked on the upper surface of each module 3 of the spent fuel storage facility 1 shown in FIG. 2, and as shown in FIG. The concave upper portion 4 of the upper module 3 is fitted into the convex upper portion 4 of the module 3, and the outlet 9 of the canister cooling air passage 6 of the lower module 3 and the inlet of the canister cooling air passage 6 of the upper module 3. 8 are connected.

The spent fuel storage facility 22 configured as described above is suitable for the case where the heat generated by the spent fuel sealed in the canister 2 of the module 3 at each stage is low and after long-term cooling. That is, when the heat generated by the spent fuel in the canister 2 of the lower module 3 is low, the air that has contributed to the cooling even when the heat is removed by the cooling air does not reach a high temperature and is low. Therefore, the low-temperature air enters the inlets 8 on the left and right inner surfaces of the concave lower portion 5 of the upper module 3 from the outlets 9 on the left and right outer surfaces of the convex upper portion 4 of the lower module 3 and passes through the canister cooling air passage. 6 to enter the storage room 10 of the upper module 3 and remove the low heat generated by the spent fuel in the canister 2 to remove the canister cooling air passage 6
And is discharged from outlets 9 on both left and right outer surfaces of the convex upper portion 6. Therefore, the spent fuel storage facility 22 is suitable for medium-term long-term storage with a low calorific value.

As shown in FIG. 9, the module 3 is stacked in three stages, upper, middle and lower, and each canister cooling air passage 6 is connected to the respective outlet 9 and inlet 8, and these are installed continuously in the lateral direction. The spent fuel storage facility 23 is suitable for the last-stage storage in which the calorific value of the spent fuel in the canister 2 is extremely low.

Therefore, the spent fuel storage facility 1 shown in FIG.
When the calorific value is attenuated after the initial storage period in which the calorific value of the spent fuel in the canister 2 is high, the module 3 is lifted by a crane, and the module 3 of the spent fuel storage facility 22 shown in FIG. As shown in FIG. 9, the module 3 is stacked by two tiers and stored for a long period in the middle period with a low calorific value. Spent fuel storage facility 23
3) to provide a final storage with a very low calorific value. By doing so, the spent fuel storage facility can increase the number of storage units in the canister 2 in accordance with the decay of the calorific value with the gradual progress of the storage period.

The modules 3 of the spent fuel storage facilities 1, 15, 22, and 23 shown in FIGS. 2, 4, 7, and 9 are adjacent to each other in the longitudinal direction, and are arranged back to back in the same arrangement. By arranging the auxiliary blocks 21 as shown by a dashed line, the size of each facility can be increased. In this case, the reason why the modules 3 are arranged back to back is to position the shielding door 12 on the outer surface of the facility.

If the entire side of the module 3 and the entire module 3 and the auxiliary block 21 of each of the spent fuel storage facilities is covered with a large earthquake-resistant wall 25 as shown in FIG. You can be absolutely sure.

The stack of the spent fuel storage module 3 and the auxiliary block 21 in each of the spent fuel storage facilities 1, 15, 22, and 23 shown in FIGS. 2, 4, 7, and 9 has a convex shape. The convex and concave shapes of the upper part 4, concave lower part 5, concave upper part 16, concave lower part 17 are rectangular in cross section and stacked from above. However, in order to improve the seismic resistance of the spent fuel storage facility, As shown in FIG. 11 and FIG. 12, the convex upper part 4, the concave lower part 5, and the concave upper part 16, the concave lower part 17 of the auxiliary block 21 have the convex upper part 4, the concave lower part 17 of the spent fuel storage module 3 in a dovetail shape in cross section. It is preferable that the sheet be slid laterally from the longitudinal direction and stacked.

[0025]

As can be seen from the above description, the spent fuel storage module of the present invention can horizontally store one canister in which spent fuel is sealed and can be stacked into an upper convex shape and a lower concave shape. The canister cooling air passage is formed in the vertical direction, the inlet is opened laterally on the left and right inner surfaces of the concave lower part, and the outlet is opened laterally on the left and right outer surfaces of the convex upper part. Therefore, the natural ventilation of the air in the vertical canister cooling air passage can efficiently remove the heat of the spent fuel, which is effective for the initial storage with a high calorific value (decay heat) of the spent fuel.

Further, in one of the spent fuel storage facilities of the present invention, the spent fuel storage modules are arranged continuously in the horizontal direction, so that the efficiency of heat removal of spent fuel is high and the amount of heat generation is high. It is effective for the initial storage of spent fuel with high (decay heat).

The auxiliary block according to the present invention has an upper concave shape and a lower concave shape. Cooling air passages are formed vertically on both sides, and an inlet and an outlet are formed in the left and right portions of the concave lower portion and the concave upper portion. Since it is opened on the side, it is stacked on the spent fuel storage module, and by communicating both cooling air passages, the height of the entire passage can be increased,
The cooling effect is improved by the chimney effect, and the spent fuel can be sufficiently removed.

Further, another one of the spent fuel storage facilities of the present invention is that the auxiliary blocks are stacked on each spent fuel storage module of the spent fuel storage facility, respectively, and the cooling air of both is cooled. Because the passages are connected,
The height of the entire cooling air passage is increased, the cooling capacity is improved by the chimney effect, the flow velocity is slow, and the generated heat of the spent fuel can be sufficiently removed accordingly. When the calorific value has been sufficiently reduced, the auxiliary block can be removed to cope with the reduced calorific value.

Still another aspect of the spent fuel storage facility according to the present invention is that at least one same module is stacked on each module of the spent fuel storage facility to communicate a cooling air passage. Therefore, if used when the heat generated by the spent fuel is low, the air that contributed to the cooling even if the heat was removed by the cooling air does not reach a high temperature but is low. From the upper module to remove the low heat generated by the spent fuel. Therefore, it is effective for medium-term long-term storage or final-stage storage with a low calorific value. When the modules are stacked in one stage, two stages, and three stages in accordance with the decrease in the calorific value with the gradual progress of the storage period of the spent fuel, the storage base number of the canister increases. As a spent fuel storage facility, the utilization efficiency of the site will be extremely high.

In each of the spent fuel storage facilities of the present invention, if the modules and the like are arranged in the same arrangement and back to back in the longitudinal direction of each module and the like, the facility can be enlarged, and a large amount of spent fuel can be stored. Is possible.

In each of the spent fuel storage facilities of the present invention, the entire side surfaces of a large number of modules and the like are covered with a large-sized earthquake-resistant wall, so that radiation shielding can be ensured.

[Brief description of the drawings]

FIG. 1 is a partially sectional perspective view of a spent fuel storage module of the present invention.

FIG. 2 is a schematic perspective view showing one embodiment of a spent fuel storage facility of the present invention.

FIG. 3 is a partially sectional perspective view of an auxiliary block according to the present invention.

FIG. 4 is a schematic perspective view showing another embodiment of the spent fuel storage facility of the present invention.

FIG. 5 is a sectional perspective view of the spent fuel storage facility of FIG.

FIG. 6 is a graph showing an attenuation curve of a calorific value (decay heat) of a spent fuel.

FIG. 7 is a schematic perspective view showing still another embodiment of the spent fuel storage facility of the present invention.

FIG. 8 is a schematic sectional view of the spent fuel storage facility of FIG. 7;

FIG. 9 is a schematic perspective view showing still another embodiment of the spent fuel storage facility of the present invention.

FIG. 10 is a schematic perspective view showing still another embodiment of the spent fuel storage facility of the present invention.

FIG. 11 is an end view showing another shape of the spent fuel storage module of the present invention.

FIG. 12 is an end view showing another shape of the auxiliary block of the present invention.

FIG. 13 is a partially cutaway perspective view of a horizontal storage module in a conventional horizontal modular spent fuel storage system.

[Explanation of symbols]

 Reference Signs List 1,15,22,23 Spent fuel storage facility 2 Canister 3 Spent fuel storage module 4 Convex upper part 5 Concave lower part 6 Canister cooling air passage 7 Shield wall 8 Inlet 9 Outlet 10 Storage room 16 Concave upper part 17 Concave shape Lower part 18 Cooling air passage 19 Inlet 20 Outlet 21 Auxiliary block 25 Earthquake-resistant wall

Claims (7)

[Claims] 1. A module for horizontally storing one canister in which spent fuel is sealed and formed in an upper convex shape and a lower concave shape so as to be stackable, and canister cooling air communicating with a storage chamber in the module. A passage is formed in the vertical direction, the both side walls are formed as shielding walls, the inlet of the canister cooling air passage is opened laterally on the left and right inner surfaces of the concave lower part, and the outlet is formed on the left and right outer surfaces of the convex upper part. A spent fuel storage module, which is opened laterally so that an inlet and an outlet communicate with each other when the modules are stacked. 2. A spent fuel storage facility in which the spent fuel storage module according to claim 1 is continuously installed in a lateral direction. 3. A short block installed on an upper surface of the spent fuel storage module according to claim 1, wherein the block is formed in an upper concave shape and a lower concave shape, and cooling air passages are formed on both sides. An auxiliary block, which is formed in a vertical direction, has an entrance opening laterally on both left and right inner surfaces of a concave lower portion, and an exit opening laterally on both left and right inner surfaces of a concave upper portion. 4. The auxiliary block according to claim 3 is stacked on the upper surface of each spent fuel storage module of the spent fuel storage facility according to claim 2, and the auxiliary block is provided on the convex upper part of each module. While the concave lower part is fitted,
A spent fuel storage facility, wherein an outlet of a canister cooling air passage is connected to an inlet of a cooling air passage of an auxiliary block. 5. The same module is stacked on the upper surface of each spent fuel storage module of the spent fuel storage facility according to claim 2 in one or two stages, and the concave portion of the upper module is placed on the convex upper portion of the lower module. A spent fuel storage facility, characterized in that the lower part is fitted and the outlet and the inlet of the canister cooling air passage are connected. 6. A spent fuel storage module according to any one of claims 2, 4 and 5, which is adjacent to the longitudinal direction of each spent fuel storage module and which is back-to-back in the same arrangement.
A spent fuel storage facility comprising an auxiliary block. 7. The whole spent fuel storage module or a large number of spent fuel storage modules and auxiliary blocks of the spent fuel storage facility according to claim 6 are covered with large-sized earthquake-resistant walls. A spent fuel storage facility.