JP2003227897A - Refilling device for vertical loading of spent fuel of reactor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a refilling device for the vertical loading of spent fuel of a reactor which can prevent beforehand the temperature of a fuel cladding tube or a concrete storage container in a canister from excessively rising and can maintain the integrity of the canister even if refilling work continues for a long time. <P>SOLUTION: A natural air-cooling duct 1 which can release the heat in the main body 12 of the refilling device and can shield it from radiation is placed in the upper part of the main body 12 of the refilling device. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refueling device for vertical loading of spent fuel in a nuclear reactor.

[0002]

2. Description of the Related Art Conventionally, spent fuel of a nuclear reactor in a nuclear power plant was stored by submerging it in a pool filled with water to cool decay heat. For those whose decay heat has decreased, dry storage has been adopted in which they are stored in a special container and then stored in the air.

The dry storage includes a so-called concrete cask system, in which a spent fuel covered with a fuel cladding tube is loaded into a metal canister, and the canister is carried into a transportation cask for storage. The canister is transported to a facility, and the canister is refilled from a transportation cask to a concrete storage container by using a refilling device in the storage facility, and the concrete storage container is stored. The heat emitted from the spent fuel is circulated through the inside of the air supply duct provided in the concrete storage container and naturally discharged from the exhaust duct to the outside while preventing the radiation emitted from the outside from leaking to the outside. It is designed to cool.

FIG. 4 shows an example of a conventional refueling device for vertical loading of spent fuel in a nuclear reactor. The refueling device 11 for vertical loading is a tubular refilling device having an open lower surface. A canister suspending tool 14 for suspending a metallic canister 13 in which a spent fuel covered with a fuel cladding tube is loaded is disposed inside the main body 12 so as to be capable of being hoisted and lowered by driving a hoisting device 15. The canister 1
When refilling the concrete storage container 18 of No. 3,
After the canister 13 is transferred from the transport cask (not shown) to the inside of the refilling device main body 12, the yoke 16 hung from the crane (not shown) is hooked on the trunnion 17 of the refilling device main body 12 to refill the refilling device main body 12. And the lower end opening of the refilling device main body 12 is connected to be placed on the upper end opening of the concrete storage container 18, and in this state, the hoisting device 15 is driven to drive the canister lifting device 1
The canister 13 hung on the No. 4 is lowered and dropped into the concrete storage container 18, and then the refilling device main body 12 is separated from the concrete storage container 18 and lifted, and the upper end opening of the concrete storage container 18 is cut off. Are to be closed.

An air supply duct 19 is provided below the concrete storage container 18, and an exhaust duct 20 is provided above the concrete storage container 18, and the exhaust duct 20 is installed in the canister 13. The heat emitted from the spent fuel is cooled by the ventilation that flows through the inside of the concrete storage container 18 from the air supply duct 19 and is naturally discharged from the exhaust duct 20 to the outside.

[0006]

However, in the conventional refilling device for vertical loading of spent fuel of the nuclear reactor as described above, when the canister 13 is refilled into the concrete storage container 18, the canister is placed in the refilling device main body 12. If the refilling work continues for a long time for some reason while the 13 is suspended, the natural heat radiation from the outer surface of the refilling device body 12 does not sufficiently remove the heat, and the inside of the canister 13 is not removed. An excessive temperature rise of the fuel cladding tube and the concrete storage container 18 occurred, which was not preferable.

In view of the above situation, the present invention can prevent the excessive temperature rise of the fuel cladding tube and the concrete storage container in the canister even when the refilling work is continued for a long time. An object of the present invention is to provide a refueling device for vertical loading of spent fuel of a nuclear reactor which can maintain soundness.

[0008]

SUMMARY OF THE INVENTION The present invention provides a refill device for vertical loading of nuclear reactor spent fuel for refilling a canister loaded with spent fuel into a concrete storage container for refilling. The present invention relates to a refueling device for vertical loading of spent fuel in a nuclear reactor, characterized in that a natural air cooling duct capable of releasing heat inside the refueling device body and shielding radiation is provided on the refilling device body.

According to the above means, the following effects can be obtained.

When the canister is refilled into a concrete storage container, even if the refilling work continues for a long time due to some reason, not only the heat is naturally radiated from the outer surface of the refiller body but also the natural air cooling duct inside the refiller body Since the heat is released, the heat can be removed satisfactorily, and the temperature of the fuel cladding tube and the concrete storage container in the canister does not rise excessively.

In the refueling device for vertical loading of the spent fuel of the nuclear reactor, the natural air cooling duct can be a screw duct.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an example of an embodiment for carrying out the present invention. In the figure, the parts designated by the same reference numerals as those in FIG. 4 represent the same parts, and the basic structure is the same as that of the conventional example shown in FIG. However, as shown in FIG. 1, the feature of the illustrated example is that the refill device main body 12 is provided on the upper part of the refill device main body 12 as shown in FIG.
Natural air-cooled duct that can release heat inside and shield radiation
There is a point.

In the case of this illustrated example, a screw duct as shown in FIG. 2 is adopted as the natural air cooling duct 1,
This is arranged on the upper surface of the main body 12 of the refill device.

Next, the operation of the illustrated example will be described.

When the canister 13 is refilled into the concrete storage container 18, even if the refilling work continues for a long time for some reason, not only the natural heat radiation from the outer surface of the refilling device body 12 but also the concrete storage container 18 The refilling device main body is formed by natural ventilation from the air supply duct 19 and the exhaust duct 20 through the concrete storage container 18 and the refilling device main body 12 to the outside from the natural air cooling duct 1 formed of the screw duct. Since the heat in 12 is released, the heat is removed satisfactorily, and the temperature of the fuel cladding tube and the concrete storage container 18 in the canister 13 does not rise excessively.

Thus, even when the refilling work is continued for a long time, it is possible to prevent an excessive temperature rise of the fuel cladding pipe in the canister 13 and the concrete storage container 18, and maintain the soundness. obtain.

FIG. 3 shows another example of the embodiment of the present invention, in which a natural air-cooled duct is provided at the upper part of the side surface of the refilling device main body 12 for radiating the heat in the refilling device main body 12 and shielding the radiation. 1 is provided.

In the case of the configuration shown in FIG. 3, as in the case of the example shown in FIG. 1, when the canister 13 is refilled into the concrete storage container 18, it is assumed that the refilling work has continued for a long time for some reason. Also, not only the natural heat dissipation from the outer surface of the refill device body 12 but also from the air supply duct 19 and the exhaust duct 20 of the concrete storage container 18 through the concrete storage container 18 and the refill device body 12,
The air naturally discharged from the natural air cooling duct 1 releases the heat in the refilling device main body 12, so that the heat can be removed satisfactorily, and the fuel cladding pipe in the canister 13 and the concrete storage container The temperature of 18 does not rise excessively, and the soundness can be maintained.

The refueling device for vertical loading of the spent fuel of the reactor of the present invention is not limited to the above-mentioned illustrated example, and the natural air cooling duct 1 can remove the heat in the refilling device main body 12. Not only the screw duct but also a zigzag duct can be used as long as it can escape and radiation can be shielded. In addition, various modifications can be made without departing from the scope of the invention. Is.

[0021]

As described above, according to the refueling apparatus for vertically loading the spent fuel of the reactor of the present invention, even if the refilling work is continued for a long time, the fuel in the canister is refueled. It is possible to prevent the excessive temperature rise of the cladding tube and the concrete storage container, and it is possible to obtain the excellent effect that the soundness can be maintained.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of an example of an embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of a screw duct as a natural air cooling duct in an example of an embodiment of the present invention.

FIG. 3 is a partially cutaway perspective view of another example of an embodiment of the present invention.

FIG. 4 is a partially cutaway perspective view of a conventional example.

[Explanation of symbols]

1 Natural air cooling duct 11 Vertical loading refill device 12 Refill device body 13 canister 14 Canister hanging equipment 15 Hoisting device 18 Concrete storage containers 19 Air supply duct 20 exhaust duct

Claims (2)

[Claims] 1. A refill device for vertical loading of a spent fuel of a nuclear reactor for refilling a canister loaded with a spent fuel so as to be hung down into a concrete storage container. A refueling device for vertical loading of spent fuel of a nuclear reactor, which is provided with a natural air cooling duct capable of radiating heat inside the refueling device body and shielding radiation. 2. The refueling device for vertical loading of spent fuel in a nuclear reactor according to claim 1, wherein the natural air cooling duct is a screw duct.