JP3735944B2 - Exothermic waste storage facility - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an exothermic waste storage facility for storing an exothermic waste such as a vitrified body obtained by vitrifying radioactive waste and a container containing spent fuel.
[0002]
[Prior art]
In recent years, it has been studied to store exothermic waste bodies such as vitrified bodies obtained by vitrifying radioactive waste liquid and containers containing spent fuel for a long period of time until the decay heat of radioactive substances is removed.
[0003]
FIG. 3 and FIG. 4 show an example of a natural-air-cooled heat-generating waste storage facility. Reference numeral 1 denotes a reinforced concrete structure, and the casing 1 is provided in the ground near the ground surface.
[0004]
Inside the housing 1 is a pit 4 in which a storage tube 3 capable of storing a waste heat generation body 2 such as a vitrified body or a container storing spent fuel is suspended in a plurality of rows in order from the front end side to the rear end side. And a cooling air inflow shaft 5 provided in front of the pit 4 and extending in the vertical direction.
[0005]
The storage tube 3 is formed in a cylindrical shape whose lower end is closed, and a plurality of heat generating waste bodies 2 can be stacked and stored in the inside in the interior thereof.
[0006]
Further, the housing 1 includes a cooling air inlet channel 6 communicating from the ground outside the housing 1 to the upper end of the cooling air inflow shaft 5, and the front end of the pit 4 from the lower end of the cooling air inflow shaft 5. An air inflow port 7 communicating with the lower part and an air outflow port 8 communicating with the ground outside the housing 1 from the rear end upper part of the pit 4 are provided.
[0007]
Further, the casing 1 has an exothermic waste insertion port 9 that penetrates from the outside of the casing 1 to the pit 4 substantially vertically so as to correspond to the upper end of the storage tube 3.
[0008]
The heat generating waste insertion port 9 is closed by a plug 10 and a lid 11.
[0009]
The storage tube 3 is embedded in a portion constituting the ceiling of the pit 4 of the housing 1 so that the upper end portion communicates with the heat generating waste insertion port 9 described above, and is embedded in the ceiling portion of the storage tube 3. The lower part of the pit 4 is located inside the pit 4.
[0010]
On the outside of the portion of the storage tube 3 located inside the pit 4, a ventilation tube 13 that forms an air flow passage 12 between the outer periphery of the storage tube 3 is arranged in the vertical direction. 13 is supported concentrically with the storage tube 3 by a stay 14, and the outside of the ventilation tube 13 is coupled to each other by a support frame 15 and fixed to the inner surface of the pit 4.
[0011]
The lower end of the ventilation pipe 13 opens at the lower part in the pit 4, and the upper end of the ventilation pipe 13 opens at the upper part in the pit 4.
[0012]
A plate-like lower plenum forming plate 16 is provided over the entire surface between the outside in the vicinity of the lower portion of the ventilation pipe 13 and the inner peripheral surface of the pit 4. It is shut off.
[0013]
In addition, a plate-like upper plenum forming plate 17 is provided over the entire surface between the outside in the vicinity of the upper portion of the ventilation pipe 13 and the inner peripheral surface of the pit 4. Blocked up and down.
[0014]
In the exothermic waste storage facility shown in FIGS. 3 and 4, when the exothermic waste 2 is stored in the storage tube 3, the decay heat of the radioactive material contained in the exothermic waste 2 is transmitted to the air in the air flow passage 12. As the temperature of the air in the air flow passage 12 rises, an air flow that flows out of the housing 1 through the air flow passage 12, the upper part of the pit 4, and the air outlet 8 is generated, and from the outside of the housing 1. An air flow that flows into the air flow passage 12 through the cooling air inlet flow path 6, the cooling air inflow shaft 5, the air inlet 7, and the lower part of the pit 4 is generated, and is built in the heat generating waste body 2 by this air flow. The decay heat of the radioactive material will be removed.
[0015]
[Problems to be solved by the invention]
However, in the exothermic waste storage facility shown in FIG. 3 and FIG. 4, even when the exothermic waste 2 is stored only in a part of each storage pipe 3, it is almost evenly distributed in each of the air flow passages 12. Since the air flow circulates, for example, when the exothermic waste body 2 is stored only in a very small number of storage tubes 3, the amount of air flow inflowing into each air flow passage 12 tends to decrease. Present.
[0016]
Therefore, even when the exothermic waste body 2 is stored only in a very small number of storage tubes 3, in order to be able to remove the decay heat of the radioactive substance contained in the exothermic waste body 2 without any trouble, It is necessary to limit the radioactive material to be installed in the heat generating waste body 2 according to the flow rate of the air flow in each of the air flow passages 12 assumed when the heat generating waste body 2 is stored only in a very small number of storage tubes 3. is there.
[0017]
The present invention has been made in view of the above-described circumstances, and even when a heat generating waste body is stored only in a very small number of storage pipes, the air flow passage associated with the storage pipe storing the heat generating waste body is provided. It is an object of the present invention to provide an exothermic waste storage facility that does not reduce the flow rate of the air flow.
[0018]
[Means for Solving the Problems]
In order to achieve the above object, in the heat generating waste storage facility of the present invention, a pit provided in the ground and a plurality of rows in order from the front end side to the rear end side of the pit are suspended inward from the pit. A storage pipe provided therein and capable of storing a heat-generating waste body therein, a ventilation pipe externally fitted to each of the storage pipes so that an air flow passage can be formed between the storage pipes, and a lower part of the ventilation pipe A lower plenum forming plate that closes between the outer peripheral surface in the vicinity and the inner peripheral surface of the pit, and an upper plenum forming plate that closes between the outer peripheral surface in the vicinity of the upper portion of the ventilation pipe and the inner peripheral surface of the pit. And an air inlet provided at the lower front end of the pit so as to be positioned below the lower plenum forming plate, and an air flow provided at the upper rear end of the pit so as to be positioned above the upper plenum forming plate. Under the exit and inside the pit And the longitudinal direction of the movable partition plate sections to and pit the space back and forth in the space below the plenum forming plate, and a moving mechanism for moving the partition plate in the longitudinal direction of the pits.
[0019]
In the exothermic waste storage facility of the present invention, when exothermic waste is stored only in a very small number of storage tubes, the exothermic waste is stored in the storage tube on the front end side of the pit, and the exothermic waste is stored. If the partition plate is moved to a position immediately below the boundary between the few rows of storage tubes and other rows of storage tubes that do not contain heat generating waste, the air flow flowing into the pit from the air inlet will generate heat. It flows into an air flow passage associated with a storage pipe storing waste.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described based on illustrated examples.
[0021]
1 and 2 show an example of an embodiment of the exothermic waste storage facility of the present invention. In the figure, the same components as those in FIGS.
[0022]
In the exothermic waste storage facility shown in FIGS. 1 and 2, the position of the lower plenum forming plate 16 is lowered as compared with those shown in FIGS. 3 and 4 described above, and the lower end of the storage pipe 3 and the ventilation pipe 13. Of the lower plenum forming plate 16 is positioned on substantially the same horizontal plane.
[0023]
Furthermore, on the floor surface 18 of the pit 4, a guide rail 19 is laid in parallel to each other at a predetermined interval in the width direction of the pit 4 and extending in the front-rear direction (AB direction shown in FIG. 1). A partition plate 21 that is movably mounted on the guide rail 19 via the wheels 20 and that can move in the front-rear direction of the pit 4 along the guide rail 19 is provided.
[0024]
In the space below the lower plenum forming plate 16 inside the pit 4, the partition plate 21 is separated from the floor surface 18 and the pit so that the space can be divided into front and rear (directions A to B shown in FIG. 1). 4 has a height that fits between the lower end surface of the storage tube 3 that is suspended in the length 4 and a length that fits the inner width of the pit 4.
[0025]
A moving mechanism 23 is disposed in a machine room 22 provided adjacent to the rear end side of the pit 4.
[0026]
The moving mechanism 23 includes a driving device 24 and drums 25 and 25 that are driven by the driving device 24 and arranged at symmetrical positions in the width direction of the pit 4 with the driving device 24 as a center.
[0027]
Rope pulleys 26 and 26 are arranged on the floor 18 near the lower side of the storage pipe 3 on the front end side of the pit 4 so as to face the drums 25 and 25, respectively. One end of each of the ropes 27, 27 is connected to the rear end side (B side in FIG. 1) of the pit 4 of the partition plate 21, and the other end of each of the ropes 27, 27 is the length of the partition plate 21. After passing through the vicinity of the direction end portion and being wound around the rope pulleys 26, 26, it is connected to the front end side (A side in FIG. 1) of the pit 4 of the partition plate 21.
[0028]
That is, when the driving device 24 is rotated in a direction in which one end side of each rope 27, 27 is wound around the drums 25, 25 and the other end side is unwound from the drums 25, 25, the partition plate 21 moves on the guide rail 19. It moves to the rear end side (B side in FIG. 1) of the pit 4 and drives in a direction to unwind one end side of each rope 27, 27 from the drum 25, 25 and wind the other end side to the drum 25, 25. When the device 24 is rotated, the partition plate 21 moves on the guide rail 19 to the front end side of the pit 4 (A side in FIG. 1).
[0029]
Next, the operation will be described.
[0030]
When the exothermic waste body 2 is stored only in a very small number of the storage tubes 3, the heat generation waste is sequentially discarded from the storage tube 3 close to the air inlet 7 with respect to the storage tube 3 arranged on the front end side of the pit 4. The body 2 is stored.
[0031]
Further, by operating the driving device 24 of the moving mechanism 23 and rotating the drums 25 and 25 driven by the driving device 24 in a necessary direction, the heat generating waste body 2 is accommodated in the partition plate 21. It is moved along the guide rail 19 to a position immediately below the boundary between a row of a very small number of storage tubes 3 and the other storage tube 3 in which the heat generating waste body 2 is not stored, and the partition plate 21 is stopped at that position. Thus, the lower space inside the pit 4 is divided into front and rear.
[0032]
When the partition plate 21 is stopped at the above-described position, the decay heat of the radioactive material contained in the heat generating waste body 2 is transmitted to the air in the air flow passage 12, and the temperature of the air in the air flow passage 12 increases. The air flow passage 12, the upper part of the pit 4, the air flow flowing out of the housing 1 through the air outlet 8 is generated, and the cooling air inlet channel 6, the cooling air inflow shaft 5, the air flow from the outside of the housing 1 are generated. An air flow flowing into the air flow passage 12 through the inlet 7 and the lower portion of the pit 4 is generated. The air flow flowing into the lower portion of the pit 4 from the outside of the housing 1 is generated by the partition plate 21 by the heat generating waste body 2. Is prevented from flowing to the rear end side of the pit 4 rather than the storage tube 3 in which the heat generation waste is stored, so that most of the air flow from the outside of the housing 1 is stored in the storage tube 3 in which the heat generating waste body 2 is stored. Air flow passage 1 associated with It flows into, thus, in the case where the heat generating waste 2 in the housing tube 3 of very few are housed also the flow rate of the air flow to the air flow passage 12 associated with the housing tube 3 is sufficiently ensured.
[0033]
That is, in the exothermic waste storage facility shown in FIGS. 1 and 2, the partition plate 21 that can divide the lower space inside the pit 4 in the front-rear direction at an arbitrary position accommodates a very small number of exothermic waste bodies 2. If it is positioned slightly behind the pit 4 from the row of the storage tubes 3, the decay heat of the radioactive substance contained in the heat generating waste body 2 stored in the storage tube 3 can be removed without any trouble.
[0034]
The exothermic waste storage facility of the present invention is not limited to the above-described embodiment, and it is needless to say that various changes can be made without departing from the gist of the present invention.
[0035]
【The invention's effect】
As described above, according to the exothermic waste storage facility of the present invention, the following various excellent effects can be achieved.
[0036]
(1) When storing a very small number of exothermic wastes in the storage pipe, the storage pipe arranged near the air inlet is selected and stored, and the partition plate is located at the rear end of the pit nearest to the storage pipe. If it is located on the side, it is possible to sufficiently secure the flow rate of the air flow with respect to the air flow passage associated with the storage pipe.
[0037]
(2) Since the flow rate of the air flow with respect to the air flow passage associated with the storage pipe can be ensured as described above, the decay heat of the radioactive material contained in the heat generating waste housed in the storage pipe can be removed without any trouble. be able to.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing a concept of an example of an embodiment of an exothermic waste storage facility according to the present invention.
FIG. 2 is a view taken in the direction of arrows II-II in FIG.
FIG. 3 is a perspective view showing an example of a conventional exothermic waste storage facility.
4 is a longitudinal sectional view showing a concept of the exothermic waste storage facility of FIG. 3. FIG.
[Explanation of symbols]
2 Exothermic waste 3 Storage tube 4 Pit 7 Air inlet 8 Air outlet 12 Air flow passage 13 Ventilation pipe 16 Lower plenum forming plate 17 Upper plenum forming plate 21 Partition plate 23 Moving mechanism

Claims (1)

A pit provided in the ground, and a storage pipe that is provided so as to hang inward from the front end side to the rear end side of the pit in a plurality of rows and can store a heat-generating waste body therein, respectively. Closes the ventilation pipe fitted around each of the storage pipes so that an air flow passage can be formed between the storage pipe and the outer peripheral surface near the lower portion of the ventilation pipe and the inner peripheral surface of the pit. The lower plenum forming plate, the upper plenum forming plate closing the space between the outer peripheral surface near the upper portion of the ventilation pipe and the inner peripheral surface of the pit, and the front end of the pit so as to be positioned below the lower plenum forming plate An air inlet provided in the lower part, an air outlet provided in the upper part of the rear end of the pit so as to be positioned above the upper plenum forming plate, and a lower part than the lower plenum forming plate inside the pit. In the space And a partition plate that is movable in the longitudinal direction of the pits, heating waste storage facility, characterized by comprising a moving mechanism for moving the partition plate in the longitudinal direction of the pits.

Images