JPH0570799B2 - - Google Patents

Description

[Detailed description of the invention] Industrial applications The present invention relates to a method for transporting radioactive waste.

Conventional technology In transportation methods in which radioactive waste such as radioactive equipment contaminated with radiation is removed from a cell and stored or destroyed at a radioactive waste processing facility, a large single container that can be shielded and sealed is used. It was meant to be used and transported. As shown in FIG. 11, for example, the transport container 71 includes a container body 72 having a thick shielding wall, a shielding wall 78 that can be raised and lowered, a shielding sheet 74, and a cover provided at the front opening of the main body 72. This container 71 is positioned in front of the cell port of the hot cell, and a manipulator or the like inside the cell is used to open the container 71.
Radioactive waste is inserted into the container 71, and the waste inside the container 71 is sealed and shielded by the blocking wall 73, the shielding sheet 74, and the cover body 75. Next, this transport container 71 was transported to a processing facility, and each container 71 was processed within the facility.

Problems to be Solved by the Invention According to the above-mentioned conventional method, shielding and sealing are performed using a single container, which results in a large and heavy transport container, which requires a crane or a transport trolley with large capacity. . Furthermore, if the container is damaged due to an accident during transportation, there is a risk that radioactivity will immediately leak and contaminate the surrounding area.

The purpose of the present invention is to provide a method for transporting radioactive waste that is low in cost, can significantly reduce radioactive contamination and exposure to the surrounding environment and workers, and is safe. .

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention uses a shielding container that removably stores a sealed container, and positions the shielding container main body at the front of the cell port. move the cell port to face the inside of the cell port, connect the cell port to the sealed container main body by a sealing member, and after inserting the radioactive waste into the sealed container main body through the cell port and the sealing member, maintain the sealing member in a sealed state. The sealed container body and the shielding container body are each attached with a lid and shielded, and then the shielding container is transported to an outside-of-cell facility, and within this outside-of-cell facility,
After removing the lid of the shielding container, the sealed container is taken out from the shielding container body, radioactive waste is disposed of together with the sealed container, and the shielding container is reused.

Effect: In the above method, a shielding container and a sealed container that is removably housed in the shielding container are used, the sealed container body is faced into the cell port, and the waste is inserted into the sealed container through the sealing member. Since radioactive waste is stored and transported in sealed containers and shielded containers, radioactive contamination to the surrounding environment can be reduced, and radiation exposure to workers can also be greatly reduced. In addition, since the sealed container is removed and processed with the lid still attached inside the facility outside the cell, the shielded container can be recovered and reused without radioactive contamination.

Embodiment An embodiment of the present invention will be described below based on the drawings.

1 to 4, 1 is a cylindrical shielding container consisting of a shielding container body 2 and a shielding container lid 3, and the shielding container body 2 has a peripheral shielding body 5 around a cylindrical body 4. a peripheral wall 7 attached by shield mounting bolts 6; a rear wall 11 attached to the rear surface of a rear plate 8 fixed to the rear part of the cylinder 4 by shielding bolts 6; a rear shield 9 and a bearing shield 10; and a front plate 12 fixed around the front end of the cylindrical body 4, and the shielding container lid 3
It is composed of a cover plate 13 and a cover shield 14 fixed to the front surface of the cover plate 13 by shield mounting bolts 6.
Hanging fittings 15 are provided at the upper and lower ends of the peripheral wall 7 for hanging the transport container with a crane or the like. The rear plate 8 and the front plate 12 are respectively formed with leg portions 8a and 12a extending downward from both sides, and a bottom plate 17 reinforced with ribs 16 is fixed to the lower end of the leg portions 8a and 12a, so that the shielding container 1 can be placed on the floor. It is now possible to place it on The shielding container lid 3 can be attached or removed by screwing a shielding container lid mounting bolt 19 inserted into a bolt hole 18 formed in the lid 3 into a screw hole 20 in the front end surface of the cylinder 4 of the shielding container main body 2. It can be taken freely. Reference numeral 21 denotes guide pins 21 for the shielding container lid that protrude from both sides of the front end of the cylindrical body 4, and are used to position the lid 3 when the lid 3 is attached. 22
A is a shielding plug that seals the bolt hole 18.

Reference numeral 23 denotes a sealed container housed within the shielding container 1, which includes an outer can body 24 having a cylindrical shape and an open front surface, an outer can lid body 25, and a sealed container that is slidably housed within the outer can body 24. It consists of 26 internal units. Around the opening of the outer can main body 24,
A PVC port 27 is formed and the outer can body 24
A vinyl chloride bag (hereinafter referred to as a PVC bag) 28a with an outer can covering the opening is attached. A flange 29 for attaching a lid is provided around the rear of this PVC port 27.

The outer can lid 25 includes a circular front plate 25a larger than the outer diameter of the outer can main body 24, and this front plate 2.
An annular peripheral plate 25 whose front end is fixed to the peripheral part of 5a
b, and a lid flange 25c fixed to the outer periphery of the rear end of the peripheral plate 25b, and the front plate 2
5a is removably attached to the rear surface of the lid plate 13 of the shielding container lid 3 via the lid fixing bolt 30, and the lid flange 25c is inserted into the female screw hole 29a of the lid attachment flange 29 of the outer can body 24. It is detachably attached using an outer can lid attaching bolt 31 that is screwed on. The front part of the outer can lid mounting bolt 31 is connected to the hole 25d of the lid flange 25c.
The shield container body 3 is rotatably held, and is configured to be detachable from a rotary tool through a through hole 32 formed in the shielding container body 3. 22B and 22C are through holes 32
and a shielding plug for sealing the fixing bolt 33 of the lid fixing bolt 30, 34 is a guide pin for the outer can lid, and 35 is a hanging bolt mounting hole formed in the center of the front surface of the front plate 25a.

The inner can 26 has a cylindrical shape that is slidably fitted into the outer can main body 24, and is open at the front and has a notch 26b continuous with the front opening 26a on the upper surface of the front.

The depth length of the outer can main body 24 is such that when the outer can main body 24 is completely housed in the shielding container main body 2, the outer can lid 25 is attached to the shielding container lid 3. The outer can lid 25 is set so that it can be set on the outer can main body 24 at the same time when the shielding container main body 2 is set. I can do it.

Reference numeral 37 denotes an outer can egress/exit device that supports the outer can main body 24 in a removable and retractable manner, and includes a front bearing 38 provided above the opening inside the cylinder 4 of the shielding container main body 2 and a front part provided above the front surface of the rear plate 8. A ball screw shaft 40 is rotatably supported at both ends by a rear bearing 39.
, a sliding boss 40 having a ball screw nut 41a screwed onto the ball screw shaft 40, and a disc-shaped bush 4 attached to the lower part of the sliding boss 41.
2, and a bushing mounting seat 43 from which a bushing retainer 43a that engages around the bushing 42 is removed and whose lower part is fixed to the upper surface of the outer can main body 24.
It consists of In the front bearing 38, a front bearing seat 44 that engages the bearing 38 is removably attached to the cylindrical body 4 with a bearing mounting bolt 45.
The rear end of the ball screw shaft 40 is connected to the rear bearing seat 4.
6, the rear plate 8 of the rear wall 11 and the bearing shield 10
Through holes 46a, 8b, 10 respectively formed in
a, the end surface of which is exposed to the surface of the shield 10, and an engagement hole 48 is formed through which the ball screw shaft 40 is rotated by a handle 47. Further, the rear end portion of the ball screw shaft 40 is removably fitted into the rear bearing 39 and supported. 49 is the shielding container body 2
It is a guide plate that guides the insertion of the outer can main body 24 inside, and its base end is fixed to the cylindrical body 4 on both sides and below of the outer can main body 24, and the tip is fixed to the cylindrical body 4 on both sides and below of the outer can main body 24.
It is configured so that it can be moved in and out in the axial direction of 4.

Next, referring to FIGS. 5 to 10, a method for transporting radioactive waste will be explained.

An extra-cell shield 52a that shields the area around the cell port 53 of the hot cell 52 is attached to the cell port 53.
Installed at the front, shielding container 1 and sealed container 23
The trolley 51 with each lid body 3, 25 removed
It is mounted on top and located in front of the cell port 53.

After removing the cell port cover body 53b, the ball screw shaft 40 of the outer can egress device 37 is rotated by the handle 47 to project the outer can main body 24 forward, and the inner can 26 is completely exposed with the notch 26b. pull it out to the desired position. Next, remove one end of the cylindrical PVC bag 28 from the PVC port 2 around the tip of the canon body 24.
7, and connect the other end to the cell PVC port 53a.
Comes with a primary cell that can be removed and covers the cell port 53 opening.
A PVC bag 54 is included, and the cell port 53 and the outer can main body 24 are communicated with each other. At this time, the loosened PVC bag 28 is secured near the PVC port 27 with a rubber band or the like. (Fig. 5) After removing the PVC bag 54 with the primary cell and inserting it into the inner can 26, open the PVC port shutter door 55, make the outer can main body 24 protrude further, and insert the front end of the inner can 26 into the cell inner shield. 5
Move it to just before 6.

After removing the cell internal shielding body 56 using a manipulator, the trolley 51 is moved forward and the front portions of the inner can 26 and the outer can main body 24 are inserted into the cell 52. At this time, the PVC bag 28 is rolled up and secured with a band or the like.

While lifting and transporting the contaminated equipment 57 with an in-cell crane, and lowering the contaminated equipment 57 through the opening 26a and cutout 26b of the inner can 26,
It is inserted into the inner can 26 using the manipulator 58. (FIG. 6) The lifting tool of the in-cell crane is removed from the contaminated equipment 57 by the manipulator 58, the contaminated equipment 57 is pushed deep into the inner can 26, and the inner can 26 is further pushed into the outer can main body 24. (FIG. 6) The outer can main body 24 is housed in the shielding container main body 2 by operating the outer can moving device 37, and then the trolley 51 is moved backward and the shielding container main body 2 is pulled out to the outside of the cell port 53.

After closing the PVC port shutter door 55,
Tie knots 59 at two points in the middle of the PVC bag 28, cut the center portions of the tied points 59,
PVC bag 28 with secondary cell PVC bag 28
Separate into b and PVC bag 28a with outer can.
(Fig. 7) The outer can cover 25 is fixed by an overhead crane, and the inside of the bolt holes 18, 33 and the through hole 3 are fixed.
2. Lift up the shielding container lid 3 with the shielding plug 22 set and transport it to the front of the shielding container main body 2, and align each lid 8 with the shielding lid guide pin 21 and the outer can lid guide pin 34. 25 to each main body 2, 24. (Fig. 8) Remove the shielding plugs 22A from the bolt holes 18 for attaching the shielding container lid one by one, insert and screw the shielding container lid attachment bolts 19, and then attach the shielding plugs 22A again. , the lid body 3 is fixed to the shielding container body 2.

Shielding plugs 22B for each through hole 32
Remove the outer can lid body mounting bolt 31 by screwing it into the female screw hole 29a of the lid body mounting flange 29 using a rotating tool, reinstall the shielding plug 22B, and attach the outer can lid body to the outer can body 24. 25 is fixed.

The transport container is transported from the experiment or manufacturing facility where the hot cell 52 is placed to the cell of the waste treatment facility using a trolley 51, a crane, etc., and is brought in in an upright state with the lid 3 positioned upward.

Remove the lid fixing bolt 30 that fixes the shielding container lid 3 and the outer can lid 25, then remove the shielding container lid mounting bolt 19, and then remove the front bearing mounting seat 44 of the ball screw shaft 40. Remove the bearing mounting bolt 45 that secures the.

The shielding container lid 3 is lifted up with an in-cell crane and removed from the shielding container main body. (FIG. 9) Screw the hanging bolt 60 into the hanging bolt mounting hole 35 of the outer can lid 25, and then tighten the hanging bolt 60.
Ball screw shaft 40 with in-cell crane through
Then, the sealed container 28 is lifted out from the front bearing seat 44, and the contaminated equipment 57 is stored or destroyed together with the sealed container 23.

A sealed container including another ball screw shaft and a front bearing seat is attached to the shielding container main body 2 carried out of the processing facility, and the container is used together with the shielding container lid 3 again to transport radioactive waste.

Effects of the Invention As described above, according to the present invention, since a transportation container consisting of a shielding container and a sealed container that is removably housed in the shielding container is used, radioactive contamination of the surrounding environment is reduced. It is possible and safe. Furthermore, since the sealed container main body faces into the cell port and the waste can be inserted from the cell port into the sealed container main body through the sealing member, the radiation exposure to workers can be greatly reduced. Furthermore, after being transported to a facility outside the cell, only the sealed container can be taken out, and the shielded container can be recovered and reused without radioactive contamination, thereby reducing costs.

[Brief explanation of the drawing]

1 to 10 show an embodiment of the present invention,
Fig. 1 is a side sectional view showing the transport container, and Figs. 2 and 3 are - sectional views and - shown in Fig. 1.
A sectional view, FIG. 4 is a partially cutaway plan view of the same part, and FIGS. 5 to 10 show the transportation method.
FIG. 6 is a partially enlarged sectional view showing the same operation, and FIGS. 7 and 8 are a side sectional view showing the insertion operation and a view taken along the arrow shown in FIG. Cross-sectional views shown in FIGS. 9 and 10
Each figure is a cross-sectional view showing the operation of taking out a sealed container, and FIG. 11 is a side cross-sectional view showing a conventional transport container. 1... Shielding container, 2... Shielding container body, 3
...shielding container lid, 23... sealed container, 24...
...Outer can body, 25...Outer can lid body, 25a
...Front plate, 25b ... Circumferential plate, 25c ... Lid flange, 25d ... Hole, 26a ... Front opening, 26b ... Notch, 28 ... PVC back,
51...Dolly, 52...Hot cell, 53...Cell port, 57...Contaminated equipment, 59...Tie point.

Claims (1)

[Claims] 1. When transporting radioactive waste inside a cell to a facility outside the cell, a shielding container that removably stores a sealed container is used, and the main body of the shielding container is positioned in front of the cell port and the sealed container is moved. The cell port is connected to the sealed container main body by a sealing member, and after inserting the radioactive waste into the sealed container main body through the cell port and the sealing member, the sealing member is cut while maintaining the sealed state. , after attaching lids to the sealed container main body and the shielding container main body for shielding, transporting the shielding container to a facility outside the cell, and removing the lid of the shielding container within the facility outside the cell. . A method for transporting radioactive waste, characterized in that the sealed container is extracted from the shielded container body, the radioactive waste is processed together with the sealed container, and the shielded container is reused.