JP4324765B2 - Method of placing radioactive waste in disposal hole and cylindrical sleeve used for placement method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, in geological disposal of high-level radioactive waste, TRU waste, etc. (hereinafter referred to as “radioactive waste”) generated by reprocessing nuclear fuel, the geological disposal container storing the waste is subjected to predetermined disposal. The present invention relates to a method for placement in a hole and a sleeve with a guide portion used in the placement method.
[0002]
[Prior art]
Since radioactive waste contains radionuclides with an extremely long half-life, it is necessary to treat radionuclides so that they do not leak out for an extremely long time.
Therefore, when disposing of radioactive waste, it has been studied to store it in a sealed container and bury the geological disposal container in the bedrock deep underground (hereinafter referred to as “geological disposal”).
[0003]
Specifically, in the radioactive waste receiving facility 1A installed on the ground as shown in FIG. 1, first, a vitrified solid body that is radioactive waste is, for example, a cylindrical carbon steel thick container ( The cover is welded and sealed after it is housed in an overpack and covered. Such a geological disposal container in which the vitrified body is stored is hereinafter referred to as “waste body”.
[0004]
The waste body 2 passes through the resist 1B connected to the deep underground disposal site after undergoing inspection and the like, and is transferred to the underground underground disposal site by a dedicated transport device having a shielding function. The geological disposal site has a large number of disposal tunnels 1C drilled in the bedrock 8, and the floor is provided with cylindrical bottomed disposal holes 3 vertically at regular intervals as shown in FIG. The waste body 2 is placed in the disposal hole 3 by a placement device (not shown). At this time, a buffer material 4 for preventing leakage of radionuclide from the waste body 2 and diffusion to the surroundings is provided. Installed at the top, bottom, and surroundings. Here, the arrangement of the buffer material 4 and the waste body 2 in the disposal hole 3 or the receiving holes 5A and 5B described later by insertion or the like is referred to as “stationary”.
[0005]
Eventually, the disposal tunnel 1C itself is also backfilled with buffer material or rock, and the disposal is completed.
For example, the following procedure is assumed for placing the cushioning material and the waste in the disposal hole.
First, it is a bottomed cylindrical shape as a cushioning material, has an opening at one end thereof, and an integrated cushioning material capable of storing one waste body in the cylindrical inner space is opened in the disposal hole by a stationary device. Insert and place with face up.
[0006]
Next, the waste body is inserted and placed in the fixed integrated cushioning material by another prepared fixing device. Furthermore, a lid cushioning material is inserted and placed on the waste, and when these series of operations are completed, the same operation is performed in the next disposal hole (for example, see Patent Document 1).
Also, as an alternative, first insert a thick disk-shaped bottom cushioning material that is slightly smaller in diameter than the disposal hole at the bottom of the disposal hole and place it horizontally, and then place the outer diameter slightly smaller than the disposal hole than the diameter of the waste body. A method of stacking a plurality of thick annular side cushioning materials having a large inner diameter on the bottom cushioning material at the bottom of the disposal hole and placing the waste body and the lid cushioning material after reaching an appropriate height has also been studied.
[0007]
These operations are performed in an environment where the radiation dose rate from the waste inside the waste body is high to some extent, even if shielding is necessary. It is assumed that it is basically performed by remote control for the work in the tunnel.
[0008]
[Patent Document 1]
Japanese Patent Laid-Open No. 9-211196 (2nd page)
[0009]
[Problems to be solved by the invention]
By the way, since the buffer material 4 is for preventing the leakage of radionuclides and diffusion to the surroundings, the buffer material 4 and the disposal material are disposed at the stage where the buffer material 4 and the waste body 2 are installed in the disposal hole 3. If there is a very large gap between the body 2 and the effect, the effect may be lost. However, on the other hand, if there is no gap at all, the waste body 2 cannot be inserted and placed in the space in the installed cushioning material 4. As described above, since these operations are assumed to be performed remotely, it is assumed that such a stationary operation is extremely difficult.
[0010]
Moreover, since the buffer material 4 currently assumed is a mixture of a kind of clay (bentonite) and silica sand, a part of the buffer material 4 is caused by the collision of the waste body 2 and the buffer material 4 during the placement operation. It may be assumed that the function is not sufficient.
Further, when it takes a long time from placing the cushioning material 4 to placing the waste body 2, the inner side surface of the cushioning material 4 exposed in the accommodation hole 3 is damaged due to falling rocks or the like. In some cases, the function cannot be performed sufficiently.
[0011]
As a means for solving these problems, an invention has been proposed in which a metal cover is provided on a housing hole for housing a waste body of an integrated cushioning material (see, for example, Patent Document 1). Since the covering member cannot be recovered and remains in the cushioning material, it is necessary to evaluate the influence of the metal covering member after disposal, which may cause problems such as cost.
Moreover, when stacking annular side cushioning materials, it becomes difficult to insert and place the waste body unless the centers of all the stacked side cushioning materials are aligned.
[0012]
The present invention makes it possible to easily insert and place the waste body in the space in the cushioning material even by remote control without increasing the gap between the waste body and the cushioning material so as to reduce the effect of the cushioning material. In addition, it is possible to prevent damage to the cushioning material due to collision between the waste body and the cushioning material, etc., to protect the cushioning material installed for a certain period of time, and to correct the position of the side cushioning material, It is an object of the present invention to provide a radioactive waste disposal method that does not leave a metal-coated member in a cushioning material, and a cylindrical sleeve that can be suitably used in the method.
[0013]
[Means for Solving the Problems]
  In order to solve the above-described problem, according to the invention of claim 1, a buffer material is placed in a disposal hole provided in a geological disposal site, and the geological disposal container is radioactively disposed in a storage hole formed inside the buffer material. A method for placing radioactive waste into a disposal hole for placing a waste containing waste, before placing the wasteA main body that is a cylinder with openings at both ends, and a funnel-shaped gas that is located at the upper end opening of the main body.Cylindrical sleeve with idIn the receiving holeWearingThe main body is substantially in close contact with the side wall of the receiving hole.In addition, after the waste body is guided by the guide portion of the cylindrical sleeve and placed in the accommodation hole, the tubular sleeve is pulled out and collected, and a method for placing the radioactive waste in the disposal hole is provided. Is done.
[0014]
  In the present invention, a cylindrical threeThe main body of theThe cushioning material is attached to the side wall of the accommodation hole so that the cushioning materialIn the main body of theTherefore, since there is no risk of damage to the buffer material due to the collision between the waste body and the buffer material, the gap between the waste body and the buffer material can be set to a minimum. Also, when inserting wasteIs a funnel-shaped gasThe id portion guides and the waste body can be smoothly inserted into the cylindrical sleeve, and remote operation becomes easy. Further, after the waste body is placed or after the waste body and the lid cushioning material are placed, the sleeve can be pulled out and collected to be used repeatedly.
[0015]
As a method of mounting the cylindrical sleeve in the accommodation hole formed in the cushioning material, a method of inserting the cylindrical sleeve into the accommodation hole after placing the integrated cushioning material in which the accommodation hole is formed in the disposal hole (claim) 2) Or a method of placing an integrated cushioning material in which a cylindrical sleeve has been inserted into the accommodation hole in advance into the disposal hole (Claim 2), a disk-like bottom cushioning material placed on the bottom of the disposal hole and the bottom cushioning material A method of fitting a cylindrical sleeve into an accommodation hole formed by an annular side cushioning material stacked on the bottom cushioning material (Claim 3), a cylindrical shape standing on the bottom cushioning material and the bottom cushioning material Any of the methods (Claim 4) for putting the buffer material into the space formed by the sleeve and the disposal hole may be used. In addition, the guide portion of the cylindrical sleeve has a replaceable structure, and the cylindrical sleeve having the guide portion through which the side cushioning material is fitted is erected on the bottom cushioning material, and a plurality of annular side cushioning members are provided. It is also possible to replace only the guide portion with one that can be used for placing the waste body after forming the accommodation hole by inserting and stacking the cylindrical sleeves. Further, in order to make the operation easier when inserting the cylindrical sleeve into the formed accommodation hole, a cylindrical sleeve that can be divided in the axial direction is attached to the accommodation hole for each divided sleeve piece. Alternatively, the divided sleeves may be bundled and inserted into the accommodation hole, and after the insertion, each divided sleeve piece may be pressed against the inner wall of the accommodation hole and attached (Claim 7).
[0016]
  When placing the waste body as described above, as a cylindrical sleeve that can be suitably used, both endsOpeningThe main body is a thin metal cylinder, and is placed and fixed on the upper end opening of the main body,It has a funnel shape that expands upward toward the waste to be accommodated,A cylindrical sleeve (Claim 8) is provided, characterized by comprising a guide portion for guiding the waste body into the accommodation hole.
  In order to facilitate the placement of the waste body in the accommodation hole, the cylindrical sleeve includes a guide portion that guides the waste body to the accommodation hole and is also used as a grip for collection, and a waste body and a cushioning material. To prevent damage to the cushioning material due to contact, and to protect the side surface of the side of the exposed hole inside the cushioning material, or to correct the misalignment of the central axes of multiple side cushioning materials, between the installation of the cushioning material and the placement of the waste body A cylindrical main body is provided.
[0017]
  Furthermore, in consideration of the case where the cylindrical sleeve is installed on the bottom cushioning material after placing the bottom cushioning material and the side cushioning material is subsequently inserted, the guide portion 1 and the side cushioning material that facilitate the insertion of the side cushioning material are used. It is good also as a structure which can replace | exchange the guide part 2 which makes insertion of a waste body easy after placement..
That is, in the present invention according to claim 9, the cylindrical sleeve is selectively and detachably placed and fixed and inserted into the main body part which is a thin metal cylinder with both end openings and the upper end opening of the main body part. A first guide portion having a reverse funnel shape toward the side cushioning material, and a funnel that is selectively and detachably placed and fixed to the upper end opening of the main body portion, and expands upward toward the waste body to be accommodated When the side cushioning material is inserted into the space formed between the main body portion placed in the disposal hole and the side wall of the disposal hole, the first guide portion is configured with a second guide portion having a shape. When the waste body is placed in the receiving hole formed by inserting the side cushioning material, the second guide portion is placed and fixed on the main body portion. To.
  Alternatively, in the case where the cylindrical sleeve is inserted and mounted in the accommodation hole, a cylindrical sleeve that can be divided in the axial direction may be used in order to facilitate such an operation.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 3 shows an example of a cylindrical sleeve 10 having a guide portion used for carrying out the method of the present invention. The cylindrical sleeve 10 is composed of a main body portion 10a having a thin cylindrical shape and open at both ends, and a guide portion 10b having a funnel shape mounted and fixed on the upper opening of the main body portion 10a and expanding upward. Is done. The inner diameter of the main body 10 a is slightly larger than the diameter of the waste body 2, and the outer diameter is set slightly smaller than the diameter of receiving holes 5 </ b> A and 5 </ b> B described later formed by the buffer material 4. The height of the main body portion 10a is substantially the same as the depth of the accommodation holes 5A and 5B, but the height at which the guide portion 10b and the cushioning material 4 do not interfere when the cylindrical sleeve 10 is inserted into the accommodation holes 5A and 5B. To do. Of course, the inner diameter and the outer diameter of the lower end of the guide portion 10b match those of the main body portion 10a, and the inner diameter, height and shape of the upper end guide the waste body smoothly when the waste body 2 is inserted. In consideration of being able to be inserted into the receiving holes 5A and 5B.
[0019]
The material of the cylindrical sleeve 10 is not particularly limited, but even when it is thin, when it is inserted into the receiving holes 5A, 5B, or when the waste body 2 is inserted into the mounted cylindrical sleeve 10, resistance or resistance It is desirable to have a metal material that has a strength that does not cause buckling or deformation against force, has a smooth surface that does not easily generate frictional resistance, and is excellent in corrosion resistance in a tunnel atmosphere. Stainless steel is preferably used.
[0020]
The lower end portion of the guide portion 10b may be fixed to the main body portion 10a by welding or the like, but may be structured to be removable by fitting to the main body portion 10a instead. In the case of the fitting structure, the lower end portion of the guide portion 10b can be fitted to the main body portion 10a separately, and a guide portion 10c having a reverse funnel-like structure is prepared, and the guide portions 10b and 10c are appropriately replaced. Therefore, it can be used as in the third embodiment described later.
[0021]
Next, a method of placing the cushioning materials 4A to 4C, the lid cushioning material 4D and the waste body 2 using the cylindrical sleeve 10 will be described.
A first embodiment according to the present invention will be described with reference to FIGS.
FIG. 4 shows an example in which an integrated cushioning material 4A is inserted and placed in a disposal hole 3 drilled in the disposal tunnel 1C, and the waste body 2 and the lid cushioning material 4D are placed in the cushioning material 4A using a cylindrical sleeve 10. It shows the inserted and placed state.
[0022]
More specifically, the disposal hole 3 is vertically drilled in the disposal tunnel 1C, and has a bottomed cylindrical shape corresponding to the cushioning material 4A. The integrated cushioning material 4A placed in the disposal hole 3 has a thick cylindrical structure with a bottom, and has an accommodation hole 5A having an opening 51a at one end. When the cylindrical waste body 2 is accommodated in the accommodation hole 5 </ b> A, the waste body 2 is positioned at a substantially central portion of the disposal hole 3. A thick disc-shaped lid cushioning material 4D is inserted into the opening 51a, and enters the waste body 2 placed in cooperation with the integrated cushioning material 4A or to the periphery of the radionuclide leaked from the waste body 2 The spread of The thickness of the lid cushioning material 4D is set in consideration of the thickness necessary for shielding. In this embodiment, a cylindrical sleeve 10 that can be inserted up to the receiving hole bottom 51b is prepared.
[0023]
  Next, a method for placing the waste body 2 according to the first embodiment will be described with reference to FIGS.
  The integrated cushioning material 4A is inserted and placed in the disposal hole 3 by a dedicated placing device (not shown) (FIG. 5A).
  Next, the cylindrical sleeve 10 is inserted into the lower end portion 10 of the main body portion 10a by a dedicated insertion device (not shown) from the accommodation hole opening 51a.dInsert until the bottom 51b of the hole is reached (FIGS. 5B and 5C). That is, before the waste body 2 is placed, the side wall of the accommodation hole 5AThe main body 10a is substantially omittedTo adhereTubeThe sleeve 10 is attached. At this time, since the guide portion 10b of the cylindrical sleeve 10 is above the upper surface of the cushioning material 4A, it does not touch and damage the cushioning material 4A. In this state, the inserted cylindrical sleeve 10 body part 10aIt acts as protection of the side surface of the accommodation hole 5A of the cushioning material 4A.
[0024]
Next, a dedicated placement device 6 for placing the waste body 2 in the accommodation hole 5A is installed on the disposal hole 5A (FIG. 5D). The stationary device 6 has a cylindrical shape to be shielded, and has a shielding door 6b that accommodates the waste body 2 suspended by a lifting device (not shown) in the internal space 6a and can be opened and closed by remote control at the bottom.
By moving the shielding door 6b horizontally, the internal space 6a accommodating the waste body 2 and the accommodation hole 5A are communicated, and the waste body 2 is lowered so that the central axis of the waste body 2 and the cylindrical sleeve 10 coincide. (FIG. 5 (e)), while guiding the guide 10b, insert and place the waste body 2 in the cylindrical sleeve 10 until the lower end 2a of the waste body 2 reaches the bottom 51b of the receiving hole 5A. It is made to detach | leave from an raising / lowering apparatus (FIG.5 (f)).
[0025]
At this time, for example, as shown in FIG. 6, when the waste body 2 is inclined or the opening 51 a of the accommodation hole 5 </ b> A and the central axis of the waste body 2 are shifted from each other, There is a possibility that it cannot be inserted by contact with the material 4A, or a part of the cushioning material 4A may be damaged (FIG. 6A). However, when the cylindrical sleeve 10 is present, the waste body 2 is lowered along the surface while being in contact with the guide portion 10b. Therefore, the inclination and the deviation between the central axes are corrected, and the waste body 2 is made cylindrical. It can be easily inserted into the sleeve 10 (FIG. 6B).
[0026]
Thereafter, the lid cushioning material 4D suspended by another lifting device (not shown) in the stationary device 6 is inserted into the space above the waste body 2 inside the cylindrical sleeve 10 (FIG. 5 (f), (G)), the shielding door 6b of the stationary device 6 is returned to the original position (FIG. 5 (h)), and the stationary device 6 is moved (FIG. 5 (i)).
Thereafter, the cylindrical sleeve 10 is extracted upward by an extraction device (not shown), removed, and collected (FIGS. 5 (j) and (k)). At this time, the cylindrical sleeve 10 can be easily pulled out by gripping the guide portion 10 b of the cylindrical sleeve 10.
[0027]
When the above operation is completed, the operation moves to the next disposal hole and the same operation is repeated. After the disposal of the waste body and the buffer material is completed for all the disposal holes, the disposal holes themselves are backfilled with the buffer material or rocks, and the disposal is completed.
In the present embodiment, the integrated cushioning material 4A is inserted into the disposal hole 3 and placed in a state where the cylindrical sleeve 10 is not inserted into the accommodation hole 5A. The cylindrical sleeve 10 may be inserted in advance into the accommodation hole 5A of the material 4A, and the integrated cushioning material 4A may be inserted into the disposal hole 3 and placed in a state where the cylindrical sleeve 10 is incorporated.
[0028]
In the present embodiment, the waste body 2 and the lid cushioning material 4D are inserted and placed by the same placing device 6, but each can be placed by a different placing device. Further, in this embodiment, not only the waste body 2 but also the lid cushioning material 4D is inserted and placed using the cylindrical sleeve 10, but the cylindrical sleeve 10 is placed before the lid cushioning material 4D is placed. It is also possible to extract and remove.
[0029]
Next, a second embodiment of the present invention will be described with reference to FIG. The cylindrical sleeve 10 used in the present embodiment is the same as that of the first embodiment, but as the cushioning material 4B, a bottom cushioning material 42a and a required number of annular side cushioning materials 42b are used. The side cushioning material 42b has an annular shape with a required thickness whose outer diameter is slightly smaller than the inner diameter of the disposal hole 3, and whose inner diameter is slightly larger than the outer diameter of the waste body 2. The thickness is set in consideration of the depth of the disposal hole 3, the thickness of the bottom cushioning material 42a, the height of the waste body 2, and the thickness of the lid cushioning material 4D placed on the disposal body 2.
[0030]
A thick disk whose diameter is slightly smaller than the inner diameter of the disposal hole 3 by a dedicated mounting device (not shown) at the bottom 3a of the bottomed cylindrical disposal hole 3 drilled in the disposal tunnel 3 (FIG. 7A). The bottom cushioning material 42a having a shape is horizontally inserted and placed (FIG. 7B).
Next, on the bottom cushioning material 42a in the disposal hole 3, a plurality of side cushioning materials 42b are sequentially inserted until they reach the required height by a dedicated placement device (not shown), stacked and placed (see FIG. 7 (d)).
[0031]
Next, the cylindrical sleeve 10 is inserted into the receiving hole 5B formed from the bottom cushioning material 42a and the stacked side cushioning material 42b, and the tip 10d of the main body 10a reaches the bottom cushioning material 42a by a dedicated insertion device. Is inserted and inserted (FIGS. 7E and 7F). At this time, as in the first embodiment, the guide portion 10b of the cylindrical sleeve 10 is above the upper end of the stacked cushioning material 42b, so that it does not touch and damage the cushioning material 42b. In the state, the inserted cylindrical sleeve 10 acts as a protection of the side surface of the accommodation hole 5B of the side cushioning material 42b.
[0032]
In the present embodiment, when the side cushioning material 42b is stacked, the side cushioning materials 42b are slightly shifted from each other in the horizontal direction, and are formed by the side cushioning material 42b in the stacked side cushioning material 42b. Since the central axis of the cylindrical space deviates from the central axis of the other cylindrical space, the side cushioning material 42b interferes with the waste body 2 when the waste body 2 is inserted, and there is a possibility that proper insertion and placement cannot be performed. Even in such a case, when the cylindrical sleeve 10 is inserted, the lower end portion 10d pushes the side cushioning material 42b in the radial direction, and the displacement of the cushioning material 42b is corrected. Placement can be performed easily.
[0033]
Thereafter, the waste body 2 is inserted and placed in the attached cylindrical sleeve 10, and the lid cushioning material 4 </ b> D is inserted and placed on the waste body 2, and then the cylindrical sleeve 10 is pulled out and removed. Is implemented by the same method as in the first embodiment.
Next, a third embodiment according to the present invention will be described with reference to FIG.
The cylindrical sleeve 10 according to the present embodiment has a structure in which the above-described guide portion 10b is detachable, and is used by appropriately fitting the guide portion 10b and the guide portion 10c to the main body portion 10a. As in the second embodiment, the bottom cushioning material 42a and the required number of annular side cushioning materials 42b are used.
[0034]
Similarly to the second embodiment, the bottom cushioning material 42a is horizontally inserted and placed in the bottom 3a of the bottomed cylindrical disposal hole 3 bored in the disposal tunnel 3 (FIGS. 8A and 8B). .
Next, the guide portion 10b of the cylindrical sleeve 10 is removed, and instead of the guide portion 10c fitted to the main body portion 10a, the centers of the guide portions 10b are aligned with each other on the bottom cushioning material 42a by a dedicated placement device. It stands up so that the part 10c may become upper (FIG.8 (c)).
[0035]
While inserting the cylindrical sleeve 10 in which the thick ring-shaped side cushioning material 42b is set up horizontally by a dedicated stationary device (not shown), the disposal hole 3 is successively reached until the set height is reached. Insert, stack and place (Fig. 8 (d)). At this time, a gap is not generated between the bottom cushioning material 42a and the side cushioning material 42b or the side cushioning material 42b. When inserting the cushioning material 42b, it is possible to easily stack the side cushioning material 42a with the center axis of the other side cushioning material 42a by inserting the guide portion 10c having a reverse funnel shape and guiding the body portion 10a. (FIGS. 8D and 8E).
[0036]
After the insertion of the cushioning material 42b, the guide part 10c exposed above the upper end of the cushioning material 42b is removed and the guide part 10b is fitted to the main body part 10a by a dedicated exchanging device (not shown) (FIG. 8 (f )). That is, the guide part 10c and the guide part 10b are exchanged.
Thereafter, the waste body 2 is inserted and placed in the inserted cylindrical sleeve 10, and the lid cushioning material 4 </ b> D is inserted and placed on the waste body 2, and the tubular sleeve 10 is further pulled out and removed. Is implemented by the same method as in the first embodiment.
[0037]
Next, a fourth embodiment of the cylindrical sleeve 10 according to the present invention will be described with reference to FIG. In the present embodiment, as the cushioning material 4C, the same bottom cushioning material 42a and granular, gravel-like or pebbled cushioning material 43b as in the second embodiment are used.
Similarly to the second embodiment, the bottom cushioning material 42a is horizontally inserted and placed in the bottom 3a of the bottomed cylindrical disposal hole 3 bored in the disposal tunnel 1C.
[0038]
Next, the cylindrical sleeve 10 is erected so that the centers thereof coincide with each other on the bottom cushioning material 42a and the guide portion 10b is located on the bottom cushioning material 42a by a dedicated placement device, and the disposal hole 3, bottom cushioning material 42a, and cylinder The cushioning material 43b is filled into the space 7 formed by the cylindrical sleeve 10 by a dedicated filling device (not shown) to a height set from the height of the waste body 2 and the thickness of the lid cushioning material to form the cushioning material. .
[0039]
Thereafter, the waste body 2 is inserted and placed in the fixed cylindrical sleeve 10, and the lid cushioning material 4 </ b> D is inserted and placed on the waste body 2, and the cylindrical sleeve 10 is further pulled out and removed. Is implemented by the same method as in the first embodiment.
Next, an embodiment of the cylindrical sleeve 11 according to the present invention will be described with reference to FIGS. As in the first embodiment of the cylindrical sleeve 10, the cushioning material 4A is inserted and placed in the disposal hole 3 as shown in FIG. 11 (a) or FIG. 12 (a).
[0040]
Next, in the axial direction, for example, the cylindrical sleeve 11 divided into four parts is placed on the bottom surface 51b with a bottom side end as shown in FIG. 11 (c) or FIG. 12 (d) by a dedicated insertion device (not shown). Wear by inserting until it reaches. At this time, the parts (divided sleeve pieces) 11a to 11d of the sleeve 11 divided into four parts may be mounted by inserting one by one along the inner wall of the accommodating hole 5A formed in the cushioning material 4A. (FIG. 11 (b)) Four pieces may be bundled and inserted, and after insertion, the divided sleeve pieces 11a to 11d may be attached by being pressed against the inner wall of the receiving hole 5A (FIG. 12 (b)). (C)). More specifically, the divided sleeve pieces 11a and 11c are arranged so as to oppose each other at an interval that can be inserted into the receiving hole 5A, and the other divided sleeve pieces 11b and 11d are opposed to each other in a space sandwiched between 11a and 11c. (Fig. 13). At this time, the divided sleeve pieces 11b and 11d are held in a slightly floating state with respect to the divided sleeve pieces 11a and 11c so that the guide portions do not interfere with each other. The divided sleeve pieces 11a to 11d are inserted into the accommodation hole 5A while being bundled as described above, and are attached by pressing against the inner wall of the accommodation hole 5A so as to be expanded by a dedicated jig (not shown) after insertion.
[0041]
Thereafter, the waste body 2 is inserted and placed in the fixed cylindrical sleeve 11, and the lid cushioning material 4 </ b> D is inserted and placed on the waste body 2, and the cylindrical sleeve 11 is further pulled out and removed. Is implemented by the same method as in the first embodiment.
At this time, the cylindrical sleeve 11 may be extracted by extracting the divided sleeve pieces 11a to 11d one by one, or by extracting four pieces at a time.
[0042]
In the present embodiment, the cylindrical sleeve 11 is mounted in the accommodation hole 5A formed using the same cushioning material 4A as the first embodiment related to the cylindrical sleeve 10. According to the method shown in the second embodiment, the cylindrical sleeve 11 may be attached to the accommodation hole 5B formed using the bottom cushioning material 42a and the side cushioning material 42b.
[0043]
【The invention's effect】
According to the method of the present invention, before placing the waste body, a cylindrical sleeve having a guide portion is attached so as to be in close contact with the side wall of the accommodation hole, and is guided by the guide portion of the cylindrical sleeve. After the waste body is placed in the receiving hole, the cylindrical sleeve is pulled out and collected. (1) Even if the gap between the waste body and the cushioning material is not increased so as to reduce the effect of the cushioning material, it can also be operated remotely. The waste body can be easily inserted and placed in the space inside the buffer material, (2) the buffer material is prevented from being damaged due to the collision between the waste body and the buffer material, and (3) the buffer installed for a certain period of time. The material is also protected, and (4) an effect is obtained that it can be collected and used repeatedly after the work is completed. In addition, when the side cushioning material is used, (5) position correction of each side cushioning material is also possible.
[0044]
Further, the above-mentioned effect can be obtained by using a structure in which the guide part for inserting the waste body can be replaced, and replacing another guide part for inserting the side cushioning material in the same manner as the replaceable structure. In addition to this, (6) the effect of facilitating the insertion of the side cushioning material and the placement is also achieved.
Furthermore, the cylindrical sleeve is divided in the axial direction, and each divided sleeve piece is attached to the receiving hole, or the divided sleeve pieces are bundled and inserted, and after insertion, they are attached by pressing against the inner wall of the receiving hole. It is possible to easily attach the sleeve.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an example of an entire geological disposal facility for radioactive waste.
FIG. 2 is a schematic cross-sectional view showing an example of a state of geological disposal of radioactive waste according to the prior art.
FIG. 3 is a schematic perspective view showing an example of a cylindrical sleeve 10 used in the method of the present invention.
FIG. 4 is a schematic cross-sectional view showing an example of a stationary state of a waste body and a buffer material according to the method of the present invention.
FIG. 5 is a flowchart showing a procedure of a first embodiment using a cylindrical sleeve 10, which is a method for placing a waste body and a buffer material according to the method of the present invention.
FIG. 6 is a schematic cross-sectional view for illustrating that placing the waste body by the method of the present invention facilitates the insertion of the waste body and does not damage the cushioning material.
FIG. 7 is a flowchart showing a procedure of a second embodiment that uses a cylindrical sleeve 10 as a method of placing a waste body and a buffer material according to the method of the present invention.
FIG. 8 is a flowchart showing a procedure of a third embodiment of the waste body and cushioning material placement method using the cylindrical sleeve 10 according to the method of the present invention.
FIG. 9 is a flowchart showing a procedure of a fourth embodiment of the waste body and cushioning material placement method using the cylindrical sleeve 10 according to the method of the present invention.
FIG. 10 is a schematic perspective view showing an example of a cylindrical sleeve 11 used in the method of the present invention.
FIG. 11 is a flowchart showing a procedure of a first embodiment of a method for placing a waste body and a buffer material according to the method of the present invention and using a cylindrical sleeve 11;
FIG. 12 is a flowchart showing a procedure of a second embodiment in which the waste body and the cushioning material are placed by the method of the present invention and the cylindrical sleeve 11 is used.
FIG. 13 is a schematic perspective view showing an example of a state in which divided sleeve pieces are bundled in a second embodiment using a cylindrical sleeve 11;
FIG. 14 is a schematic plan view showing an example of a state in which divided sleeve pieces are bundled in a second embodiment using a cylindrical sleeve 11;
[Explanation of symbols]
2 Waste
3 disposal holes
4 cushioning material
4A Integrated cushioning material
4B cushioning material
4C cushioning material
4D lid cushioning material
42a Bottom cushioning material
42b Side cushioning material
43b cushioning material
5A accommodation hole
5B accommodation hole
10 Tubular sleeve
10a Body
10b Guide part (for waste)
10c Guide part (for side cushioning material)
11 Tubular sleeve
11a Split sleeve piece
11b Split sleeve piece
11c Split sleeve piece
11d Split sleeve piece

Claims (10)

A waste of radioactive waste in which a buffer material is placed in the disposal hole provided in the geological disposal site, and a waste containing radioactive waste is placed in the storage hole formed in the buffer material. A method of placing the material in the disposal hole,
Wherein prior to placing the waste, and the body portion is cylindrical at both ends opening, a tubular sleeve having a guide portion forming a funnel shape located at the upper end opening of the main body portion and instrumentation wear in the housing bore, aft by substantially close contact with the main body portion on the side wall of the accommodation hole,
A method for placing radioactive waste in a disposal hole, wherein the waste is guided by the guide portion of the cylindrical sleeve and placed in the accommodation hole, and then the cylindrical sleeve is pulled out and collected. 2. The method for placing radioactive waste in a disposal hole of a radioactive waste according to claim 1, wherein an integrated cushioning material in which a housing hole is formed is placed in the disposal hole. Place a disc-shaped bottom cushioning material at the bottom of the disposal hole,
A plurality of annular side cushioning materials are sequentially inserted into the disposal holes, stacked on the bottom cushioning material, and the cylindrical sleeve is fitted into a receiving hole formed by the bottom cushioning material and the plurality of side cushioning materials. The method of placing the radioactive waste in the disposal hole of the waste according to claim 1. Place a disc-shaped bottom cushioning material at the bottom of the disposal hole,
The cylindrical sleeve is erected on the bottom cushioning material with the guide portion facing up,
The buffer material is filled in a space defined by a disposal hole, a bottom cushioning material, and a cylindrical sleeve to form a cushioning material, and the radioactive waste to the disposal hole of the waste body according to claim 1, Placement method. The cylindrical sleeve is capable of appropriately replacing the first guide part for inserting the side cushioning material and the second guide part for inserting the waste body,
Place a disc-shaped bottom cushioning material at the bottom of the disposal hole,
The cylindrical sleeve on which the first guide part is mounted is erected on the bottom cushioning material with the guide part facing up,
A plurality of annular side cushioning materials are sequentially inserted into the disposal holes while being fitted into the cylindrical sleeve, and stacked on the bottom cushioning material,
2. The method of placing radioactive waste in a disposal hole of radioactive waste according to claim 1, wherein the waste is placed in a receiving hole after the guide portion is replaced with a second guide portion. The said cylindrical sleeve can be divided | segmented into the axial direction, and is mounted to the accommodation hole for every division | segmentation sleeve piece, The stationary placement to the disposal hole of the waste body of Claim 1 thru | or 3 characterized by the above-mentioned. Method. The cylindrical sleeve can be divided in the axial direction, and the divided sleeve pieces are bundled and inserted into the receiving hole, and after the insertion, the divided sleeve piece is pressed against the inner wall of the receiving hole and attached. A method of placing the radioactive waste according to claim 1 in a disposal hole of a waste body. A cylindrical sleeve used for a method of placing radioactive waste in a disposal hole of a radioactive waste according to claims 1 to 4 for placing a waste having a cylindrical outer surface shape,
A main body that is a thin metal cylinder with openings at both ends;
A cylinder mounted and fixed at the upper end opening of the main body, and having a funnel shape that expands upward toward the waste to be accommodated, and a guide portion that guides the waste to the accommodation hole Sleeve. A cylindrical sleeve used for a method of placing radioactive waste in a disposal hole according to claim 5 for placing a waste having a cylindrical outer surface shape, and is a thin metal cylinder having openings at both ends. The main body,
A first guide portion that is selectively and detachably mounted on the upper end opening of the main body portion , and has a reverse funnel shape toward the side cushioning material to be inserted ;
A second guide part having a funnel shape that is selectively and detachably mounted on the upper end opening of the main body part and expands upward toward the waste body to be accommodated ;
When inserting the side cushioning material into the space formed between the main body part placed in the disposal hole and the side wall of the disposal hole, the first guide part is placed and fixed on the main body part ,
A cylindrical sleeve characterized in that when a waste body is placed in an accommodation hole formed by inserting a side cushioning material, the second guide portion is placed and fixed on a main body portion . The cylindrical sleeve according to claim 8, wherein the main body portion and the guide portion can be divided in the axial direction.

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