JP3989810B2 - Granular or powdered radioactive waste containers - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a granular or powdered radioactive waste container suitable for use in containing, transporting and removing granular or powdered radioactive waste (hereinafter referred to as waste).
[0002]
[Prior art]
Various radioactive wastes are generated in the process of handling and handling radioactive materials performed at nuclear power plants and nuclear fuel processing plants. Radioactive waste is divided into radioactive gas, liquid and solid waste, and some radioactive solid waste is granular or powdery. Since this waste can be formed into a slurry using an appropriate liquid such as water as a medium, the waste is stored in a transport container for transporting such waste and is discharged from the transport container. The slurry is generally made into a slurry fluidized with water.
[0003]
In the usage form of the transport container for transporting such waste, the waste is accommodated in the transport container at the place where the waste is generated. Next, the transport container containing the waste is transported to a waste disposal site where the waste is discharged from the transport container. The transport container that has been emptied after the waste is discharged is returned again to the place where the waste is generated, and the above-described housing, transporting, and discharging operations are repeated.
[0004]
FIG. 6 is a longitudinal sectional view of a conventional waste transport container. The upper wall of the container body 1 having a radiation shielding structure for containing waste is provided with a waste input / extraction port 2 for inputting or taking out the waste, which is hermetically closed or opened. A waste-injecting / extracting lid 3 having a radiation shielding structure is provided with a fixing structure with a fastening bolt 4. The upper wall of the container body 1 is further provided with a vent nozzle 5 for exhausting the gas inside the container body 1 or press-fitting the air into the container body 1 with a fixing structure with a tightening bolt 7 via a vent cover 6. The outside of the container body 1 of the vent nozzle 5 (hereinafter referred to as an external gas introduction side) is closed by a quick joint 8. On the other hand, a discharge port 9 leading to the outside of the container body 1 is provided on the side wall adjacent to the bottom of the container body 1, a wire mesh 10 is provided at the inlet of the discharge port 9, and a drain nozzle 11 is provided at the outlet of the discharge port 9. A drain plug 14 with an O-ring having a screwed structure is attached thereto, and a drain cover 12 with an O-ring is attached to the outer side (discharge side) by a tightening bolt 13. However, the drain nozzle 11 is also used for discharging water which is a slurry medium when waste is charged in the form of water slurry.
[0005]
Next, a method for storing waste in the transport container will be described. FIG. 7 is a longitudinal sectional view of the transport container for explaining the storage method. The storage method will be described with reference to FIG. 7 and FIG. First, the drain plug 14 and the drain cover 12 are removed as preparation for discharging the water separated / generated from the waste inside the container body 1 when the waste is put into the container body 1 in the form of water slurry, A drainage metal fitting 15 for drainage is attached to the outlet of the drain nozzle 11, and a drainage hose 16 is connected thereto.
[0006]
On the other hand, on the upper wall of the container body 1, the vent cover 6 that closes the vent nozzle 5 is removed, the quick joint 8 on the external gas introduction side (upper end) of the vent nozzle 5 and the quick joint 17 on the tip of the vent hose 18. The vent hose 18 is connected via A compressed air supply mechanism (not shown) is connected to the upstream side of the vent hose 18.
[0007]
Next, the waste charging / unloading lid 3 is removed by loosening / extracting the tightening bolt 4 to open the waste charging / unloading port 2, and the waste charging hose 19 is inserted into the waste charging / discharging hose 19. Slurry waste 20 is put into the container body 1. On the other hand, the water slurry waste 20 is separated from the water slurry waste 20 through the wire mesh 10 and the drain nozzle 11 at the bottom of the container body 1 while the water slurry waste 20 is being introduced into the container body 1 from the drain hose 16 at the bottom. Drain the water. In this way, after a predetermined amount of waste is stored in the container main body 1, the waste input / extraction lid 3 is closed as it is, and further compressed air is introduced from the vent hose 18 into the container main body 1. The water intervening / mixed between the agglomerated waste is allowed to escape, and the water dehydrated from the waste is discharged from the drain hose 16 together with the compressed air through the wire mesh 10 and the drain nozzle 11 at the bottom of the container body 1. After this drainage process is completed, the drainage hose 16 and drainage fitting 15 are removed from the drain nozzle 11, the outlet of the drain nozzle 11 is closed with a drain plug 14 with an O-ring, and an O-ring is attached with a tightening bolt 13 as a secondary lid. A drain cover 12 is attached to ensure airtightness. Next, the vent hose 18 on the upper wall of the container body 1 is removed from the vent nozzle 5 by the quick joints 17 and 8, and the external gas introduction side of the vent nozzle 5 is closed by the vent cover 6. Thus, the operation of storing the waste in the transport container is completed.
[0008]
The transport container in which the waste is stored as described above is appropriately transported to a waste disposal site and then transferred from the transport container to a waste disposal container. For this purpose, the waste is removed from the shipping container.
[0009]
Next, a method for taking out the waste from the transport container will be described. FIG. 8 is a longitudinal sectional view for explaining a method for taking out waste, and the method for taking out will be described with reference to FIG. 8 and FIG. 6 described above. First, the waste loading / unloading cover 3 on the upper wall of the container body 1 is removed to open the waste loading / unloading port 2, and a high-pressure water supply hose 21 and a fluid suction hose 22 are placed inside the container body 1 from here. insert. Next, high-pressure water 23 supplied from a high-pressure water supply mechanism (not shown) connected to the upstream side of the high-pressure water supply hose 21 is supplied to the inside of the container body 1 in which waste is stored. It injects through the hose 21 and fluidizes the waste to form a water slurry waste. The obtained water slurry waste 24 is sucked by a fluid suction hose 22 through a suction pump (not shown), and the waste stored in the container body 1 is discharged.
[0010]
[Problems to be solved by the invention]
In the above-described conventional waste container, the work of taking out the waste from the container is a work that requires direct human work, which places a problem of placing a burden on the worker in a radiation and radioactive contamination environment. is there. Moreover, since the operation of taking out the waste from the transport container is to suck and discharge the slurry-like waste with a suction pump, it is difficult to completely discharge the waste from the transport container. Part remains. In addition, since a special suction pump is required to take out the waste from the transport container, the cost is high, and there are problems such as radiation exposure problems in maintenance, inspection and repair work. .
[0011]
The present invention has been made in view of such problems, and is intended to reduce the radiation exposure of workers handling waste containers and to simplify the method of handling the waste containers. An object of the present invention is to provide a granular or powdery radioactive waste container that can reduce the work load and can be handled at low cost.
[0012]
[Means for Solving the Problems]
A granular or powdered radioactive waste container according to the present invention includes a container main body for storing granular or powdered radioactive waste, an air nozzle for introducing compressed air provided at an upper portion of the container main body, and the container. A discharge port provided in a lower portion of the main body, a strainer disposed in the discharge port in the container main body, and suspended in the container main body and attached to the lower end of the strainer and supported by the container main body so as to be movable up and down And a drainage pipe and a drainage hose that are selectively attached to the discharge port, and a water injection pipe for injecting water into the container body.
[0013]
In the present invention, after introducing fluid waste containing moisture into the container body, by introducing compressed air into the container body through the air nozzle, the waste does not pass through the strainer. Only water can be drained from the outlet. When discharging waste from the container body, water is poured into the container body from the water injection pipe, the waste is fluidized, and the strainer is lifted through the rod to open the discharge port. The fluidized waste can be discharged from.
[0014]
As described above, according to the present invention, the operation of taking out the waste can be performed by remote operation outside the container, and the operator is not burdened with the work under the radiation and radioactive contamination environment. Moreover, since the operation of taking out the waste from the container is discharged from the discharge port provided in the lower portion of the container main body without passing through the strainer, the waste can be completely discharged from the container. Furthermore, a special suction pump is not required for discharging waste, and the cost is low, and there is no problem of radiation exposure during maintenance / inspection and repair work.
[0015]
This radioactive waste container has a water injection nozzle for attaching a water injection hose provided at the upper part of the container body, and the water supplied to the water injection nozzle through the water injection hose is connected to the water injection pipe. Can be injected into the container body through the water injection pipe. Thereby, water injection work becomes easy and fluidization of waste becomes easy.
[0016]
Moreover, the flange which is provided in the upper wall of the said container main body so that removal is possible, and in which the said rod, the said nozzle for air, and the said nozzle for water injection can be installed can be provided. Thereby, the nozzle for air, the rod and the strainer, the nozzle for water injection, and the water injection pipe can be removed from the container body all at once, and maintenance inspection becomes easy.
[0017]
Furthermore, by providing an opening / closing lid provided on the upper wall portion of the container main body and for introducing radioactive waste into the container main body, it becomes easy to input the waste into the container.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a waste container according to an embodiment of the present invention will be described. FIG. 1 (a) shows a longitudinal sectional view of a waste container according to an embodiment of the present invention, FIG. 1 (b) shows an enlarged view of a Q portion surrounded by a broken line circle in FIG. 1 (a), 2 shows a cross-sectional view taken along line AA in FIG. 1A, and FIG. 3 shows a view taken along line BB in FIG. The upper wall of the container body 1 composed of a cylindrical side wall, a disk-shaped bottom, and a disk-shaped upper wall is provided with a waste inlet 102 for charging waste. A waste charging lid 103 which can be hermetically closed or opened is fixed by a fastening bolt 4 so as to be detachable. The upper wall of the container body 1 is further provided with a disk-like flange 25 that is detachably fixed by a tightening bolt 35. The flange 25 has three through holes 26, 31, and 34 formed on the disk. It is provided at a substantially symmetrical position with respect to the center.
[0019]
The first through hole 26 is provided at a position closest to the center of the container body 1 among the three through holes 26, 31, 34, and the water injection pipe 30 is fixed thereto. Thereby, the water injection pipe 30 is suspended in the container main body 1. A water injection port 27 is provided at the lower end of the water injection pipe 30, and water injected from the water injection port 27 into the container main body 1 fluidizes waste inside the container main body 1. A water injection nozzle 28 for connecting a water injection hose is fixed to the first through hole 26, and the upper end portion of the water injection pipe 30 is connected to the lower end of the water injection nozzle 28. On the other hand, the connection between the water injection nozzle 28 and the water injection hose 37 (see FIG. 5 described later) is a quick coupler type. That is, a quick joint 29 is attached to the upper end of the water injection nozzle 28, and a quick joint 307 that matches the quick joint 29 is attached to the tip of the water injection hose 37. The water injection hose 37 can be attached to and detached from the nozzle 28 quickly and easily.
[0020]
The second through-hole 31 is provided at a position closest to the side wall of the container body 1 among the three through-holes 26, 31, 34, and the lifting rod 33 moves up and down with its longitudinal direction set to the vertical direction. The rod 33 can be moved up and down automatically or manually by a lifting device (not shown) via the upper end portion of the lifting rod 33. A strainer 32 that allows moisture contained in the waste to pass through but does not pass through the waste itself is provided at the lower end of the lifting rod 33, so that the moisture is separated from the waste. Yes.
[0021]
A discharge port 9 having an inlet on the bottom surface and an outlet on the bottom side wall is provided at the bottom of the container body 1 below the rod 33, and the rod 33 is lowered to connect the strainer 32 to the bottom of the container body 1. And by covering the inlet of the outlet 9 with the strainer 32, only the moisture is discharged from the outlet 9. By lifting the strainer 32 away from the inlet of the outlet 9, the outlet 9 is opened. Waste can be discharged. The rod 33 is guided by a slide type guide 30 a fixed to the middle portion of the hanging water injection pipe 30 and moves up and down, and the strainer 32 accurately descends to the inlet position of the discharge port 9.
[0022]
A quick coupler type vent (air) nozzle 5 is fixed in the third through hole 34 (see FIG. 2). The lower end of the vent nozzle 5 opens into the container body 1, and a quick joint 8 is attached to the upper end thereof. The connection between the vent nozzle 5 and the vent hose 18 (see FIG. 5 to be described later) is a quick coupler type, and the quick joint 8 of the vent nozzle 5 and the quick joint 108 attached to the tip of the vent hose 18 matching the quick joint 8 Thus, the vent hose 18 can be quickly and easily attached to and detached from the vent nozzle 5. Compressed air can be introduced into the container body 1 or the gas inside the container body 1 can be exhausted through the vent hose 18. However, when the above operation via the vent hose 18 is not performed, the external gas introduction side of the vent nozzle 5 is normally closed with a vent cover 205 having a tightening bolt 305 structure.
[0023]
As described above, the water injection pipe 30 supported by the first through hole 26 supplies water for fluidizing the waste, and separately transports the waste previously fluidized with water in advance. It can also function as an introduction pipe for introduction into the main body 1.
[0024]
Then, by removing the fastening bolt 35 of the flange 25, the water injection pipe 30, the elevating rod 33 and the vent nozzle 5 supported by the flange 25 and the flange 25 can be easily taken out from the container main body 1. In addition to the water pipe 30, the lifting rod 33 and the vent nozzle 5, all components such as the strainer 32 and the water injection nozzle 28 can be inspected and maintained outside the container body 1 by a simple operation. Moreover, since the water injection nozzle 28 and the vent nozzle 5 are quick couplers, the water injection hose 37 (see FIG. 5 to be described later) and the vent hose 18 (see FIG. 4) can also be easily removed, so that they can be inspected easily. Can do.
[0025]
The discharge port 9 provided at the bottom of the container body 1 is equipped with a drain nozzle 11 on the outlet side. The outlet end of the drain nozzle 11 is usually closed by a drain plug 14 with an O-ring having a screwed structure to ensure airtightness, and a drain cover 12 with an O-ring is provided as a secondary lid on the outside of the drain nozzle 11 with a tightening bolt 13. Airtightness is secured by being fixed to.
[0026]
Next, a method for storing waste in the above-described waste container will be described. FIG. 4 is a longitudinal sectional view of a container for explaining a waste storage method. 4A is a longitudinal sectional view of the entire container body 1 and its related members including the CC line section in FIG. 3, and FIG. 4B is a DED line section in FIG. It is sectional drawing which shows the discharge | emission side (right side of FIG. 1) half of 1. FIG. First, the drain cover 12 and the drain plug 14 (see FIG. 1A) are removed, a drainage fitting 15 is attached to the outlet of the drain nozzle 11, and a drainage hose 16 is connected thereto.
[0027]
Next, the waste input lid 103 (see FIG. 1A) is removed to open the waste input port 102. The waste input hose 19 is inserted into the waste input hose 19, and the waste fluidized with water is supplied to the waste input hose. 19 to the inside of the container body 1. During the charging period of the water slurry waste 20, the lifting rod 33 is in the lower limit position, and the lower end of the lifting rod 33 presses the strainer 32 against the bottom of the container body 1 so that the strainer 32 covers the discharge port 9. . Thereby, the moisture contained in the waste is discharged from the drainage hose 16 through the strainer 32. By this drainage, the amount of waste stored in the container body 1 can be increased to increase the storage amount, or the storage amount can be secured. In this way, after a predetermined amount of waste is stored in the container body 1 (for example, the height indicated by the two-dot chain line L1 in FIG. 4), the waste input hose 19 is removed and the waste input port 102 is disposed of as waste. It is sealed with a charging lid 103 (see FIG. 1A). Next, the vent hose 18 is connected to the vent nozzle 5, and air is press-fitted into the container body 1 from this to discharge the water remaining in the waste through the strainer 32, and the waste passes through the strainer 32. Since it does not pass, the waste can be dehydrated. After the dehydration and drainage are finished, the drain hose 16 and drain fitting 15 are removed, the drain plug 14 and the drain cover 12 are attached, and the drain nozzle 11 is closed. With the above operation, the storage of the waste in the transport container is completed.
[0028]
In addition, the operation | work which throws in the slurry-like waste 20 fluidized with water is not restricted to inserting the waste input hose 19 in the waste input port 102, but taking out the waste from the container main body 1 mentioned later The water injection pipe 30 used at the time of work can also be utilized. In this case, fluidized waste is supplied from the water injection pipe 30 into the container body 1 by connecting a supply pipe for waste fluidized with water to the water injection nozzle 28. Thus, if the water injection pipe 30 is used, it is not necessary to remove the waste input lid 103 and open the waste input port 102, so that the operation is simplified and the radiation exposure dose of the operator is reduced. .
[0029]
The transport container for radioactive waste containing the waste as described above is transported to a predetermined radioactive waste disposal site by a predetermined transport means, and then the waste is taken out from the transport container.
[0030]
Next, a method for taking out the waste from the transport container will be described. FIG. 5 shows a longitudinal sectional view of a transport container for explaining a method for taking out waste. First, the drain cover 12 and the drain plug 14 (see FIG. 1A) are removed, and the drainage fitting 15 and the drainage hose 16 are attached to the drain nozzle 11.
[0031]
Also, the vent cover 205 (see FIG. 2) is removed, the vent hose 18 is connected to the vent nozzle 5 via the quick joints 8 and 108, and the water injection hose 37 is connected to the water injection nozzle 28 via the quick joints 29 and 307. To do. Next, while exhausting air that fills the space between the granular agglomerates accommodated in the container main body 1 by the vent hose 18, water is poured from the water injection hose 37 to fluidize the waste. At this time, the position of the strainer 32 is adjusted by the lifting / lowering position control mechanism (not shown) so as to cover the inlet of the discharge port 9 at the bottom of the container main body 1 and keep it pressed from above. . This is because a sufficient amount of water is interposed and retained between the agglomerated wastes to facilitate fluidization. Water is poured in this way, and when the water surface (indicated by a two-dot chain line L2 in FIG. 5) reaches the upper surface of the waste layer, water injection from the water injection hose 37 is stopped. Next, the strainer 32 is lifted to a specified height via the lifting rod 33 and held. Thereafter, water is again injected from the water injection hose 37 through the water injection pipe 30, and the waste is discharged from the discharge hose 16 while further fluidizing.
[0032]
As described above, by using the waste transport container of the present embodiment, the strainer 32 can be easily opened by an operation from the outside of the container body 1 when the waste is taken out. It can be discharged from the drain nozzle 11. In addition, since the waste contained in the container body 1 is discharged in this way, the waste can be completely discharged without remaining in the container body 1.
[0033]
In addition, if the container for transporting waste according to the present invention is used, the air between the agglomerated waste is sucked by the vent hose 18 and then poured into the agglomerated material to fluidize it. The fluidization performance of the agglomerates with water is very good. Thereby, the hydrostatic pressure of the slurry-like waste in the initial stage of discharge becomes extremely large. Therefore, a large driving force for discharging is obtained in the first half of the discharge period, and a large inertial force is obtained by the good discharge flow movement in the first half in the second half of the discharge period, and this inertial force is maintained until the end of discharge. And good discharge behavior is obtained. Therefore, waste can be taken out from the transport container by the above-mentioned taking-out method by remote operation without any remaining residue and without requiring manual work. In the above operation, the water injection from the water injection nozzle 28 for fluidizing the waste may be performed by supplying the water from the discharge hose 16 into the container main body 1 to fluidize the waste. It is possible to discharge without leaving any waste.
[0034]
【The invention's effect】
As described above in detail, according to the present invention, the operation of containing and taking out granular radioactive waste can be performed outside the container, forcing the worker to work in a radiation and radiation-contaminated environment. There is nothing. In addition, the waste can be completely discharged from the container, and the work load such as maintenance, inspection, and repair can be reduced, and the processing cost can be reduced.
[Brief description of the drawings]
1A is a longitudinal sectional view of a granular or powdered radioactive waste container according to an embodiment of the present invention, and FIG. 1B is an enlarged view of a portion surrounded by Q in FIG.
FIG. 2 is a cross-sectional view taken along line AA in FIG.
3 is a view taken along the line BB in FIG. 1. FIG.
4 is a longitudinal sectional view of the container for explaining a method of storing waste in the granular or powdered radioactive waste container of FIG. 1, and (a) includes a CC line section in FIG. It is a longitudinal cross-sectional view over the whole container, (b) is a longitudinal cross-sectional view over the discharge side (right side) half of a container including the DED line cross section in FIG.
5 is a longitudinal sectional view of the container for explaining a method of taking out the waste from the granular or powdered radioactive waste container of FIG. 1. FIG.
FIG. 6 is a longitudinal sectional view of a conventional granular or powdered radioactive waste container.
FIG. 7 is a longitudinal sectional view of a container for explaining a method of storing waste in a conventional granular or powder radioactive waste container.
FIG. 8 is a longitudinal sectional view of a container for explaining a method for taking out waste from a conventional granular or powdered radioactive waste container.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Container main body 2; Waste input / output 102; Waste input 3; Waste input / output lid 103; Waste input lid 4; Tightening bolt 5; Vent nozzle (nozzle for air)
6; Vent cover 7; Tightening bolt 8; Quick joint (upper end of vent nozzle)
9; Discharge port 10; Wire mesh 11; Drain nozzle 12; Drain cover 13; Tightening bolt 14; Drain plug 15; Drainage metal fitting 16; Drainage hose 17;
18; Vent hose 108; Quick joint (end of vent hose)
19; waste charging hose 20; water slurry waste 21; high pressure water feed hose 22; fluid suction hose 23; high pressure water 24; water slurry waste 25; flange 205; vent cover 26; 27; Water injection port 28; Water injection nozzle 29; Quick joint (top of water injection nozzle)
30; water injection pipe 30a; sliding guide 31; second through hole 32; strainer 33; elevating rod 34; third through hole 35; tightening bolt 305; vent cover tightening bolt 37; water injection hose 307; Hose tip)

Claims (4)

A container main body for storing granular or powdered radioactive waste, an air nozzle for introducing compressed air provided in an upper part of the container main body, a discharge port provided in a lower part of the container main body, and in the container main body A strainer disposed in the discharge port, a rod that is suspended in the container body and is attached to the lower end of the strainer and supported so as to be movable up and down, and injects water into the container body. A granular or powder radioactive waste container comprising a water pipe and a drainage fitting and a drainage hose that are selectively attached to the discharge port. A water injection nozzle for attaching a water injection hose provided at the upper part of the container body is provided, and the water supply pipe is connected to the water injection pipe and the water supplied through the water injection hose is connected to the water injection hose through the water injection pipe. 2. The granular or powdered radioactive waste container according to claim 1, which is injected into the container body. The granular or powder radioactive waste according to claim 2, further comprising a flange that is detachably provided on an upper wall of the container body and on which the rod, the air nozzle, and the water injection nozzle are installed. container. 2. An opening provided on an upper wall of the container main body for introducing granular or powdered radioactive waste into the container main body, and an opening / closing lid for opening and closing the opening. The container for granular waste or powdery radioactive waste of any one of thru | or 3.

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