JPH0961596A - Radioactive waste storage and disposal facility and method for geological disposal of radioactive waste using the facility - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To cool and store radioactive waste until the decay heat is removed, and after the decay heat is removed, the radioactive waste can be disposed of underground. A sealed container storage chamber (1) capable of storing a plurality of radioactive waste sealed containers (4) formed inside an underground rock (3) and sealed with radioactive waste, and a sealed container extending from a ground surface (2) to the sealed container storage chamber (1). The container transport pit 10, the air supply pit 14 connected from the ground surface 2 to the sealed container storage chamber 1, and the exhaust pit 15 connected from the sealed container storage chamber 1 to the ground surface 2 are provided.
After the decay heat of the radioactive waste inside the radioactive waste enclosure 4 stored in is removed, the interior of the enclosure storage room 1 is filled with a bentonite-based filler to dispose the radioactive waste underground. .

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a radioactive waste storage / disposal facility and a method for geological disposal of radioactive waste using the facility.

[0002]

2. Description of the Related Art When a fuel used in a nuclear reactor of a power plant is used for about three to four years, fission products accumulate in the fuel to limit combustion, and are replaced with new ones.

Further, radioactive substances such as fuel, which has a limit of combustion, are stored in a radioactive waste storage pool provided in a power plant while being immersed in water.

[0004] This radioactive waste contains unburned uranium and plutonium generated during combustion of fuel in a state mixed with fission products, and is used to recover unburned uranium and the like from the radioactive waste. Processing operations are being carried out, and the resulting uranium and the like will be reused as fuel for nuclear reactors.

[0005]

However, the reprocessing work of radioactive waste has not been carried out in earnest at the present time, and the total amount of radioactive waste stored in the radioactive waste storage pool is It is increasing every year.

Therefore, about 10% of the radioactive waste is collected from the surface of the earth.
It is considered to perform geological disposal by burying it in underground rock of about 00 m, but it takes about 30 to 50 years until the decay heat of radioactive waste is removed. For disposal, it is necessary to cool and store radioactive waste until the decay heat is removed.

The present invention has been made in view of the above-mentioned circumstances, and the radioactive waste can be cooled and stored until the decay heat is removed, and after the decay heat is removed, the radioactive waste can be disposed in the geological formation. It is an object of the present invention to provide a storage and disposal facility so that radioactive waste can be geologically disposed in a stable state by using the radioactive waste storage facility.

[0008]

To achieve the above object, in the radioactive waste storage / disposal facility according to claim 1 of the present invention, a plurality of radioactive wastes are formed inside the underground rock and are filled with radioactive wastes. Enclosure for storing radioactive waste enclosures, an enclosure transport pit that extends from the surface to the enclosure storage room, an air supply pit that connects the surface to the enclosure storage room, and an enclosure storage room to the surface It has a series of exhaust shafts.

In the radioactive waste storage / disposal facility according to the second aspect of the present invention, there is provided a container fitting hole which is formed inside the underground rock and into which the radioactive waste enclosing container enclosing the radioactive waste can be loosely fitted. A plurality of enclosed container storage chambers on the inner bottom, an air passage formed inside the underground rock so as to communicate with the bottom of the container insertion hole, and an enclosed container transfer hole extending from the ground surface to the enclosed container storage chamber. And an air supply pit connected from the ground surface to the air flow path, and an exhaust pit connected from the enclosed container storage chamber to the ground surface.

Further, in the method for geological disposal of radioactive waste using the radioactive waste storage / disposal facility according to claim 3 of the present invention, the radioactive waste in the radioactive waste enclosing container stored in the enclosing container storage room is disposed. After the decay heat of the object is removed,
A bentonite-based filler is filled in the storage chamber of the sealed container.

According to a fourth aspect of the present invention, in the method for geological disposal of radioactive waste using the radioactive waste storage / disposal facility, in the radioactive waste enclosing container loosely fitted in the container insertion hole of the enclosing container storage chamber. After the decay heat of the radioactive waste is removed, a bentonite-based filler is filled inside the air flow path, the container fitting hole, and the sealed container storage chamber.

In the radioactive waste storage / disposal facility according to claim 1 of the present invention, air is supplied from the outside to the enclosed container storage chamber through the air supply pit, and at the same time from the enclosed container storage chamber through the exhaust pit to the outside. The air is discharged to remove the decay heat of the radioactive waste enclosed in the radioactive waste enclosure stored in the enclosure storage room.

In the radioactive waste storage / disposal facility according to claim 2 of the present invention, air is supplied to the sealed container storage chamber from the outside through the air supply pit, the air flow path, and the container fitting hole.
Air is discharged from the enclosure storage room to the outside through the exhaust pit, and the decay heat of the radioactive waste enclosed in the radioactive waste enclosure stored in the enclosure storage room is removed.

Further, the air passage is regulated by the container fitting hole, so that the decay heat of the radioactive waste enclosed in the radioactive waste enclosure can be easily removed.

In the method of geological disposal of radioactive waste using the radioactive waste storage / disposal facility according to claim 3 of the present invention,
After the decay heat of the radioactive waste is removed, the radioactive waste enclosure container containing the radioactive waste is geologically disposed by filling the inside of the enclosure storage room with a bentonite-based filler.

In the method for geological disposal of radioactive waste using the radioactive waste storage and disposal facility according to claim 4 of the present invention,
After the decay heat of the radioactive waste is removed, a bentonite-based filling material is filled inside the air flow path, the container fitting hole, and the sealed container storage chamber to form the radioactive waste sealed container in the stratum. dispose.

[0017]

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

1 and 2 show a first example of an embodiment of the radioactive waste storage / disposal facility of the present invention.

Reference numeral 1 denotes an enclosed container storage chamber. The enclosed container storage chamber 1 is made of a carbon steel plate or a stainless steel plate on the inner wall surface of a space excavated in the underground rock 3 about 1000 m from the ground surface 2. It is formed by stretching a liner member.

Between the liner member forming the enclosed container storage chamber 1 and the underground rock 3, a bentonite-based filler excellent in water-stopping property is filled.

Most of the inner bottom surface of the enclosure storage room 1 is adapted to be used as a container storage floor 6 for storing the radioactive waste enclosure 4.

The remaining portion of the inner bottom surface of the enclosure storage room 1 is the radioactive waste enclosure 4 on the container storage floor 6.
Is a work floor 7 for carrying out the transfer preparation work, and the work floor 7 is provided with a carrier truck 8.

An overhead crane 9 is provided on the ceiling of the enclosed container storage chamber 1 so as to be located directly above the work floor 7 and above the container storage floor 6.

As shown in FIG. 3, the radioactive waste enclosing container 4 has an enclosing container body 4a having an opening at the top and capable of containing the radioactive waste S therein, and an opening part of the enclosing container body 4a. It is constituted by a lid 4b which can be fitted into.

Reference numeral 10 denotes a sealed container transport pit, which is made of a carbon steel plate or a stainless steel plate on the inner wall surface of the space opened and cut from the ground surface 2 toward the work floor 7 of the sealed container storage chamber 1. Is formed by stretching the liner member.

A bentonite-based filler excellent in water-stopping property is filled between the liner member forming the enclosed container transport pit 10 and the underground rock 3.

Reference numeral 11 is an elevator, and the elevator 11 is built inside the enclosed container transport pit 10 on the surface 1 of the building 1.
It is arranged so as to be able to move up and down between 2 and the work floor 7.

The tip end of a wire rope 13 hung from the hoisting device 5 provided inside the building 12 to the enclosed container transport pit 10 is connected to the elevator 11.

Reference numeral 14 is an air intake pit, and the air intake pit 14 is a liner made of a carbon steel plate or a stainless steel plate on the inner wall surface of the space opened and cut so as to communicate from the ground surface 2 to the lower part of the enclosure storage room 1. It is formed by stretching a member.

Reference numeral 15 denotes an exhaust pit, which is provided with a liner member made of a carbon steel plate or a stainless steel plate on the inner wall surface of the space opened and cut so as to communicate with the upper surface of the sealed container storage chamber 1 from the ground surface 2. It is formed by stretching.

Between the liner members forming the air intake pit 14 and the exhaust pit 15 and the underground rock 3, a bentonite-based filler excellent in water stopping property is filled.

Further, on the surface of the earth 2, an air supply tower 16 for supplying ground air (outside air) to the air supply pit 14 and an exhaust tower 17 for exhausting the air inside the sealed container storage chamber 1 from the exhaust pit 15. Is being built.

In FIG. 2, 18 indicates a bentonite type filler.

The procedure for storing the radioactive waste S in the radioactive waste storage / disposal facility shown in FIGS. 1 and 2 will be described below.

The radioactive waste S to be stored is housed in the sealed container body 4a, the lid 4b is fitted into the opening of the sealed container body 4a, and the inside of the sealed container body 4a is filled with argon (A).
r) Filling the gas, fixing the lid 4b to the enclosure container body 4a by mechanical fastening means (not shown) such as bolts, and further enclosing the entire outer peripheral portion of the lid 4b in the enclosure container body 4
The edge of the opening a is welded and sealed, and the radioactive waste S is sealed in the radioactive waste container 4 (see FIG. 3).

Further, by the air supply tower 16 and the exhaust tower 17,
Air is circulated by natural air cooling in the order of the air supply pit 14, the sealed container storage chamber 1, and the exhaust pit 15.

The radioactive waste enclosing container 4 in which the radioactive waste S (see FIG. 3) is enclosed by circulating the air as described above.
Is transferred from the ground to the work floor 7 of the enclosed container storage room 1 by using the elevator 11, and is transferred to the vicinity of the container storage floor 6 by the transfer carriage 8.

Further, the radioactive waste encapsulation container 4 is placed on the container storage floor 6 by the overhead crane 9 (see FIG. 1), and the exhaust pit 1 is passed from the air supply pit 14 through the encapsulation container storage chamber 1.
The air flowing to 5 removes the decay heat of the radioactive waste S (see FIG. 3) contained in the radioactive waste enclosure 4, and the air that absorbed the decay heat is discharged to the outside.

As described above, in the radioactive waste storage / disposal facility shown in FIGS. 1 and 2, since the radioactive waste enclosure 4 is stored in the underground enclosure storage room 1, the radioactive waste enclosure 4 is long. It is not necessary to construct a facility for storing over a period of time on the ground surface 2, and the ground surface 2 can be effectively used.

After the decay heat of the radioactive waste S (see FIG. 3) is removed, the equipment inside the enclosure storage room 1 such as the carrier 8 and the ceiling crane 9 is removed as necessary.

After removing these devices, the enclosed container storage pit 10, the air supply pit 14, the exhaust pit 15, and the enclosed container storage chamber 1 except the work floor 7 are formed. 1 is filled with a bentonite-based filler 18 (see FIG. 2), and the radioactive waste enclosing container 4 containing the radioactive waste S (see FIG. 3) is geologically disposed in a stable state.

As described above, in the radioactive waste storage / disposal facility shown in FIGS. 1 and 2, since the encapsulation container storage chamber 1 in which the radioactive waste encapsulation container 4 is stored is used for geological disposal, radioactive waste encapsulation is performed. The geological disposal of the radioactive waste encapsulation container 4 can be carried out very rationally without carrying out the transfer work of the container 4 again.

Further, since the enclosing container transport pit 10 is not filled with the bentonite type filler 18, the radioactive waste enclosing container 4 which has been geologically disposed is dug out to store the radioactive waste S (see FIG. 3). It is also possible to reprocess.

FIGS. 4 to 7 show a second example of the embodiment of the radioactive waste storage / disposal facility of the present invention. In the drawings, the parts designated by the same reference numerals as those in FIGS. Represent the same thing.

In the radioactive waste storage and disposal facility shown in FIGS. 4 to 7, a large number of container fitting holes 20 into which a radioactive waste container 19 to be described later can be loosely fitted are formed on the container storage floor 6 of the container storage room 1. , An air flow path 21 communicating with the bottom of each of the container fitting holes 20 in the formation below the enclosed container storage chamber 1.
Is provided, and the air supply pit 14 is communicated with one end of the air flow path 21 without directly communicating with the enclosed container storage chamber 1.

As shown in FIGS. 6 and 7, the container insertion hole 20 has a large diameter portion 20a extending downward from the container storage floor 6.
An annular supporting portion 20b that projects substantially horizontally from the lower end of the large diameter portion 20a toward the center in the radial direction, and a small diameter portion 2 that extends downward from the inner edge of the supporting portion 20b and continues to the air flow passage 21.
0c and 0c.

Further, each container fitting hole 20 and the air flow path 21
Is formed by tensioning a liner member made of a carbon steel plate or a stainless steel plate on the inner wall surface of the space excavated in the underground rock 3 as in the case of the enclosed container storage chamber 1 described above, A space between the liner member forming the container fitting hole 20 and the air flow path 21 and the underground rock 3 is filled with a bentonite-based filler excellent in water stopping property.

As shown in FIG. 8, the radioactive waste enclosing container 19 has an enclosing container body 19a having an opening at the top and capable of accommodating the radioactive waste S, and is fitted into the opening of the enclosing container body 19a. The sealed container body 19a is formed with a flange portion 19c projecting outward in the radial direction.

The outer diameter of the sealed container body 19a of the radioactive waste container 19 is smaller than the inner diameter of the small diameter portion 20c of the container fitting hole 20.

The outer diameter of the flange portion 19c is smaller than the inner diameter of the large diameter portion 20a of the container fitting hole 20 and larger than the inner diameter of the small diameter portion 20c.

Further, as shown in FIGS. 6 to 8, a plurality of (about 3 to 8) leg members 22 are fixed to the lower surface of the flange portion 19c of the radioactive waste container 19 at substantially equal intervals in the circumferential direction. When the radioactive waste enclosing container 19 is fitted into the container fitting hole 20, the leg member 22 comes into contact with the support portion 20b from above.

The procedure for storing the radioactive waste S in the radioactive waste storage / disposal facility shown in FIGS. 4 to 7 will be described below.

The radioactive waste S to be stored is placed inside the enclosure body 19a, and the lid 1 is attached to the opening of the enclosure body 19a.
After inserting 9b, the interior of the enclosure body 19a is filled with an inert gas such as helium (He), and the lid 19b is attached to the enclosure body 19a by mechanical fastening means (not shown) such as bolts. The lid 19b is fixed, and the entire outer peripheral portion of the lid 19b is welded and sealed to the opening edge portion of the enclosure main body 19a to enclose the radioactive waste S in the radioactive waste enclosure 19 (see FIG. 8).

Next, the radioactive waste enclosing container 19 enclosing the radioactive waste S (see FIG. 8) is transferred from the ground to the work floor 7 of the enclosing container storage chamber 1 by using the elevator 11.
It is transferred to the vicinity of the container storage floor 6 by the carrier truck 8.

Further, the radioactive waste enclosing container 19 is moved by the overhead crane 9 into the container fitting hole 20 of the container storage floor 6.
(See FIG. 4), and the radioactive waste S contained in the radioactive waste enclosing container 19 (FIG. 8) by the air flowing from the air flow path 21 to the enclosing container storage chamber 1 through the container fitting hole 20. Heat of decay).

As described above, in the radioactive waste storage / disposal facility shown in FIGS. 4 to 7, the radioactive waste enclosing container 19 is
Since it is stored in the underground container storage room 1, a facility for storing the radioactive waste container 19 for a long period of time is installed on the ground surface 2.
The ground surface 2 can be effectively used without the need to build it.

After the decay heat of the radioactive waste S (see FIG. 8) is removed, the equipment inside the enclosure storage room 1 such as the carrier 8 and the ceiling crane 9 is removed as necessary.

After removing these devices, the enclosed container storage pit 10, the air supply pit 14, the exhaust pit 15 and the enclosed container storage chamber 1 except for the work floor 7 are formed. 1, a container fitting hole 20, and an air flow path 21 are filled with a bentonite-based filler 18 (see FIG. 5), and a radioactive waste S (see FIG. 8) is contained in the radioactive waste container 19.
Geological disposal in a stable state.

As described above, in the radioactive waste storage / disposal facility shown in FIGS. 4 to 7, since the encapsulation container storage chamber 1 in which the radioactive waste encapsulation container 19 is stored is used for geological disposal, the radioactive waste encapsulation is performed. The geological disposal of the radioactive waste encapsulating container 19 can be carried out extremely rationally without carrying out the transfer work of the container 19 again.

Further, since the enclosed container transportation pit 10 is not filled with the bentonite type filler 18, the radioactive waste enclosed container 19 which has been geologically disposed is dug out to store the radioactive waste S (see FIG. 8). It is also possible to reprocess.

The radioactive waste storage and disposal facility of the present invention and the method for geological disposal of radioactive waste using the facility are as follows:
The present invention is not limited to the above-described embodiment, and instead of attaching the leg member to the lower surface of the flange portion of the enclosure body, the leg member is attached to the upper surface of the support portion of the container fitting hole. Of course, various changes can be made without departing from the scope of the present invention.

[0062]

As described above, the radioactive waste storage and disposal facility of the present invention and the method for geological disposal of radioactive waste using the facility can exhibit various excellent effects as described below.

(1) In the radioactive waste storage / disposal facility according to claim 1 and claim 2 of the present invention, the radioactive waste enclosing container enclosing the radioactive waste is stored in the underground enclosing container storage room. , It is not necessary to construct a facility on the ground surface for storing radioactive waste encapsulation containers for a long time, and the ground surface can be effectively used.

(2) In the radioactive waste storage / disposal facility according to claim 2 of the present invention, since the air path is regulated by the container insertion hole, the decay heat of the radioactive waste enclosed in the radioactive waste enclosing container. Can be efficiently removed.

(3) In the geological disposal method for radioactive waste using the radioactive waste storage / disposal facility according to claim 3 and claim 4 of the present invention, the radioactive waste storage container is stored in an enclosed container. Since the room is used for geological disposal, the geological disposal of the radioactive waste encapsulation container can be extremely rationalized without carrying out a transfer operation of the radioactive waste encapsulation container again.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a state in which a radioactive waste enclosing container in which radioactive waste is enclosed is stored in the first example of the radioactive waste storage / disposal facility of the present invention.

FIG. 2 is a conceptual diagram showing a state in which a radioactive waste enclosing container in which radioactive waste is enclosed is geologically disposed in the first example of the radioactive waste storage / disposal facility of the present invention.

FIG. 3 is a conceptual diagram showing an example of a radioactive waste enclosure.

FIG. 4 is a conceptual diagram showing a state in which a radioactive waste enclosing container enclosing radioactive waste is stored in the second example of the radioactive waste storage / disposal facility of the present invention.

FIG. 5 is a conceptual diagram showing a state in which a radioactive waste enclosing container in which radioactive waste is enclosed is geologically disposed in the second example of the radioactive waste storage / disposal facility of the present invention.

6 is a partial cutaway view of a container insertion hole in the radioactive waste storage / disposal facility shown in FIGS. 4 and 5. FIG.

FIG. 7 is a view on arrow VII-VII in FIG.

FIG. 8 is a conceptual diagram showing another example of a radioactive waste enclosing container.

[Explanation of symbols]

 1 enclosure container storage room 2 ground surface 3 underground rock bed 4 radioactive waste enclosure container 10 enclosure container transportation pit 14 air supply pit 15 exhaust pit 18 bentonite filler 19 radioactive waste enclosure container 20 container fitting hole 21 air flow passage S radioactive waste

Claims (4)

[Claims] 1. A sealed container storage chamber that can store a plurality of radioactive waste sealed containers formed inside underground rock and sealed with radioactive waste, and a sealed container transport pit extending from the ground surface to the sealed container storage chamber. A radioactive waste storage / disposal facility comprising: an air supply pit connected from the ground surface to the enclosure storage room; and an exhaust pit connected from the enclosure storage room to the surface. 2. A sealed container storage chamber having a plurality of container fitting holes formed in the underground rock and having a radioactive waste sealed container in which radioactive waste is sealed and which can be loosely fitted, and an inside of the underground rock. An air passage formed so as to communicate with the bottom of the container fitting hole, an enclosed container transport pit extending from the ground surface to the enclosed container storage chamber, an air supply pit connected from the ground surface to the air passage, and an enclosed container A facility for storing and disposing of radioactive waste, characterized in that it comprises an exhaust pit extending from the storage room to the surface of the earth. 3. After the decay heat of the radioactive waste in the radioactive waste enclosure stored in the enclosure storage room is removed,
The method for geological disposal of radioactive waste using the radioactive waste storage and disposal facility according to claim 1, wherein a bentonite-based filler is filled inside the enclosure storage room. 4. After the decay heat of the radioactive waste in the radioactive waste enclosing container loosely fitted in the container inserting hole of the enclosing container storing chamber is removed, the air flow path, the container inserting hole, the enclosing container storing chamber The geological disposal method for radioactive waste using the radioactive waste storage and disposal facility according to claim 2, wherein the interior is filled with a bentonite-based filler.