JPH11326588A - Canister and facility for storing spent fuel, and cask for transporting the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase storage density and compact a facility by equipping a canister with a cylindrical body with an opening at one end and a lid for the canister used to block the opening, and shaping the body of the canister like a prism. SOLUTION: A body 12 of a canister and a lid 13 for it is made of metal materials so as to increase the efficiency in the removal of decay heat, and the body 12 is shaped like a prism. Since the body 12 is shaped like a prism, an unnecessary space does not appear between the inner face of the body 12 and spent fuels 15. Therefore, storage density can be increased in a storage facility and more spent fuels 15 can be stored efficiently in a pit of the facility. As an opening of the pit is shaped like a rectangle so as to fit the outer form of a canister 11, the area surrounded by four pits can be made smaller than conventional methods. This makes it possible to compact a storage facility, reduce the materials required for the construction of it and the volume of excavation, and decrease construction costs of the storage facility.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spent fuel storage canister, a spent fuel transport cask, and a spent fuel storage facility used for storing nuclear fuel used in a nuclear power plant.

[0002]

2. Description of the Related Art Nuclear fuel used in a nuclear power plant (hereinafter referred to as spent fuel) is usually transferred from a nuclear power plant to a reprocessing plant for reprocessing. Due to the balance between the amount of spent fuel generated and the processing capacity of reprocessing plants, there is an increasing need to store and store spent fuel for a long time.

When a spent fuel is stored and stored for a long period of time, one of the points to keep in mind is decay heat generated from the spent fuel. As an example of a facility for safely storing and storing the spent fuel, a spent fuel storage facility as shown in FIGS. 9 to 11 has been conventionally known.

The spent fuel storage facility shown in FIGS. 9 to 11 has a plurality of vertical pits 1 underground, and above these pits 1 is a steel container containing spent fuel 2. A mobile crane (not shown) for storing a canister (hereinafter referred to as a canister) 3 in the pit 1 is provided.

The pit 1 is surrounded by concrete 4 and an air intake 5 is provided in the vicinity of the pit 1. The air intake 5 communicates with an air introduction passage 6 provided below the pit 1, and air (outside air) flowing from the air intake 5 into the air introduction passage 6 passes through the inside of the pit 1 from below to above. After ventilating, the pit 1 is discharged from an air discharge port formed in a shielding lid 7 that shields the upper end opening of the pit 1 with radiation.

In the above-mentioned storage facility, the canister 3 containing the spent fuel 2 is cooled by the air passing through the pit 1, so that the decay heat generated from the spent fuel 2 can be removed. is there.

[0007]

However, in the above-mentioned prior art, as shown in FIG. 12, since the canister 3 has a cylindrical shape, the spent fuel 2 contained in the canister 3 and the canister 3 are not included. A useless space 8 is generated between the wall surface 3a. For this reason, the storage density (storage amount per unit area) of the storage facility described above has been reduced, and it has been difficult to store a large number of spent fuels in one pit. Further, an area (hatched portion in FIG. 13) surrounded by the four pits 1 becomes unnecessarily large, so that a useless space is generated.

The present invention has been made in view of the above problems, and has as its object to increase the storage density of a spent fuel storage facility and reduce the cost required for the construction of the facility by making the facility compact. Is what you do.

[0009]

To achieve the above object, according to the present invention, there is provided a cylindrical canister body having an opening at one end, and a canister lid for closing the opening of the canister body. Wherein the canister main body is formed in a rectangular cylindrical shape. The invention according to claim 2 comprises a cylindrical cask main body having an opening at one end for taking in and out a canister containing spent fuel, and a cask lid for closing the opening of the cask main body. In the used fuel transport cask, a positioning member for positioning and fixing the canister at a central portion of the cask main body is provided on an inner peripheral surface of the cask main body. The invention according to claim 3 is characterized in that the positioning member is formed of a metal material. According to a fourth aspect of the present invention, in the spent fuel storage facility for regularly placing canisters containing spent fuel, the opening of the underground pit is formed in a rectangular shape in accordance with the outer shape of the canister. And

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show an embodiment of the present invention. FIG. 1 is a partially sectional side view of a canister for storing spent fuel according to an embodiment of the present invention, and FIG. It is arrow sectional drawing along a line. As shown in FIG. 1, a canister 11 for storing spent fuel according to an embodiment of the present invention has a cylindrical canister body 12 having an opening at one end, and an opening of the canister body 12 is hermetically closed. A canister lid 13 and a hanging member 14 provided on the upper surface of the canister lid 13 are provided. Inside the canister body 12, a lattice-like basket 16 for vertically supporting a spent fuel 15 is provided. I have.

The canister body 12 and the canister lid 13
Is formed of a metal material such as iron in order to enhance the heat removal effect of the decay heat, and the canister body 12 is formed in a rectangular tube shape as shown in FIG.

FIG. 3 is a longitudinal sectional view of a spent fuel transport cask used when transporting the canister 11 shown in FIG. 1 from a nuclear power plant to a storage facility, and FIG. 4 is a BB of FIG.
It is arrow sectional drawing along a line. In the figure, reference numeral 17 denotes a cylindrical cask main body.
An opening is formed for taking in and out the canister 11 containing the spent fuel. Reference numeral 18 denotes a cask lid for closing the opening of the cask main body 17, and the cask lid 18 includes an inner lid 18a and an outer lid 18b.

The cask body 17 includes an inner cylindrical container 17a made of metal such as iron, a cylindrical γ-ray shield 17b provided on the outer periphery of the inner cylindrical container 17a, and an outer periphery of the γ-ray shield 17b. As shown in FIG. 2, a canister is provided on the inner peripheral surface of the inner cylindrical container 17a, and a cylindrical neutron shield 17d provided on the outer periphery of the outer cylindrical container 17c. A plurality of positioning members 19 are attached to position and fix the center 11 of the cask main body 17. These positioning members 19 are formed of the same metal material as the inner cylindrical container 17a, and are fixed by welding to the inner peripheral surface of the inner cylindrical container 17a. The positioning members 19 are formed in a plate shape, and the outer surfaces of the canister 11 containing the spent fuel are in contact with these positioning members 19.

[0014] Canister 11 containing spent fuel 15
Is stored in the spent fuel storage facility shown in FIGS. In other words, the spent fuel storage facility shown in FIGS. 4 to 8 has a plurality of vertical pits 20 underground. Above these pits 20, the canister 11 containing the spent fuel 15 is located. A mobile crane 21 is provided for storage in the interior.

The pit 20 is surrounded by concrete 22 and an air intake 23 is provided near the pit 20. The air intake 23 communicates with an air introduction passage 24 provided below the pit 20, and air (outside air) flowing from the air intake 23 into the air introduction passage 24 passes through the inside of the pit 20 from below to above. After ventilation, pit 20
Is discharged from an air outlet formed in a shielding lid 25 that shields the upper end opening of the radiation. The canister 11 containing the spent fuel 15 is housed in the pit 20 with its upper and lower parts sandwiched between an upper shield 26 and a lower shield 27 made of concrete.

In the above-described embodiment of the present invention, since the canister main body 12 is formed in the shape of a rectangular tube, there is no wasteful space between the inner surface of the canister main body 12 and the spent fuel 15. Therefore, the storage density of the storage facility described above can be increased, and more spent fuel can be efficiently stored in the pit of the storage facility.

In the above-described embodiment, the pit 20
Is formed in a rectangular shape in accordance with the outer shape of the canister 11, so that the area of the portion surrounded by the four pits 20 can be made smaller than before, so that the storage facility can be made compact, Materials needed for construction,
The amount of excavation can be reduced, and the construction cost of storage facilities can be reduced.

Further, by providing a plurality of positioning members 19 on the inner peripheral surface of the cask body 17, the canister 11
Can be positioned at the center of the cask body 17. Further, since the positioning member 19 is formed of a metal such as iron, the decay heat generated in the spent fuel 15 can be transmitted to the cask main body 17 and the decay heat generated in the spent fuel 15 is radiated to the outside. be able to.

[0019]

As described above, according to the present invention,
The storage density of the spent fuel storage facility can be increased, and more spent fuel can be efficiently stored in the pit of the storage facility.

[Brief description of the drawings]

FIG. 1 is a partially sectional side view of a spent fuel storage canister according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a longitudinal sectional view of a spent fuel transport cask used when transporting the spent fuel storage canister according to one embodiment of the present invention from a nuclear power plant to storage equipment.

FIG. 4 is a sectional view taken along line BB of FIG. 3;

FIG. 5 is a diagram showing a schematic configuration of a spent fuel storage facility for storing and storing a spent fuel storage canister according to one embodiment of the present invention together with spent fuel.

6 is a longitudinal sectional view of the storage facility shown in FIG.

FIG. 7 is a view taken in the direction of arrows along the line CC in FIG. 6;

FIG. 8 is a sectional view taken along line DD of FIG. 6;

FIG. 9 is a longitudinal sectional view of the spent fuel storage facility.

FIG. 10 is an arrow view along the line EE in FIG. 9;

FIG. 11 is a sectional view taken along the line FF of FIG. 9;

FIG. 12 is a cross-sectional view of a conventional spent fuel storage canister.

FIG. 13 is an enlarged view of a part of FIG. 10;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 12 Canister body 13 Canister lid 15 Spent fuel 16 Basket 17 Cask body 18 Cask lid 19 Positioning member 20 Pit 21 Mobile crane 23 Air intake 25 Shield lid

Claims (4)

[Claims] 1. A canister for storing spent fuel, comprising: a canister body having an opening at one end; and a canister lid for closing the opening of the canister body. A canister for storing spent fuel, wherein the canister is formed in a shape. 2. A use comprising: a cylindrical cask main body having an opening at one end for taking in and out a canister containing spent fuel; and a cask lid for closing the opening of the cask main body. A spent fuel transport cask, characterized in that a positioning member for positioning and fixing the canister at the center of the cask main body is provided on an inner peripheral surface of the cask main body. 3. The cask for transporting spent fuel according to claim 2, wherein said positioning member is formed of a metal material. 4. A spent fuel storage facility in which canisters containing spent fuel are regularly placed, wherein an opening of the underground pit is formed in a rectangular shape in accordance with an outer shape of the canister. Spent fuel storage facility.