JP6344595B2 - Air blast cutting machine - Google Patents

Description

  The present invention relates to an air blast cutting apparatus applied when collecting an overpack in which high-level radioactive waste is mainly enclosed.

  High-level radioactive waste generated by reprocessing spent fuel from nuclear power plants is a natural barrier several hundred meters below ground that is confined in an artificial barrier made of vitrified material, overpacks and cushioning materials. It is planned to dispose deep underground in the bedrock.

  Subsurface disposal requires the management of more than 10,000 years due to the extremely long half-life of the target radioactive materials. However, new disposal technology has been established after disposal or the disposal site has been changed. In that case, proposals have been made to make it possible to collect high-level radioactive waste.

  On the other hand, conventionally, since it is not assumed that high-level radioactive waste is recovered during the disposal period, new technical development for recovery has become necessary.

  As described above, the high-level radioactive waste is embedded in the buffer material in a state of being enclosed in the overpack, and in order to collect the high-level radioactive waste, it is necessary to take out the overpack from the buffer material. As the cushioning material, bentonite is selected that exhibits water-stopping properties by swelling itself even when groundwater enters.

  In response, a method has been proposed in which the bentonite is disintegrated and removed with salt water without swelling the bentonite (Patent Document 1, Non-Patent Document 1).

JP 2010-008375 A

"Buffer material removal technology using salt water for waste collection", Japan Society of Civil Engineers 65th Annual Scientific Lecture (September 2010) "Examination of bentonite barrier removal by ice blasting method", Spring Meeting of the Atomic Energy Society of Japan (March 2008)

  However, in the above-described method of breaking down bentonite using salt water, it is necessary to separately process a large amount of bentonite slurry generated at that time, and above all, a new radioactive waste such as bentonite slurry is generated.

  Moreover, in order to solve this, the method of grind | pulverizing and removing this bentonite by spraying dry ice on bentonite as a blast material is also proposed (nonpatent literature 2).

  However, the cushioning material in which the overpack is embedded has an outer diameter of 2 m or more and a height of 3 m or more.

  That is, only the above-mentioned crushing removal is exposed only in the vicinity of the top portion of the overpack, and even if an attempt is made to pull up the overpack using the exposed portion, the portion other than the vicinity of the top portion remains embedded in the bentonite. Along with the pulling, a large shear adhesive force acts on the peripheral surface from bentonite, and there is a concern that the overpack may be unexpectedly damaged.

  Therefore, a considerable part of the bentonite surrounding the overpack has to be pulverized and removed, which causes a problem that a long pulverizing and removing operation is required.

  The present invention has been made in consideration of the above-described circumstances, and provides an air blast cutting device that can safely and quickly remove an overpack from a cushioning material without generating new radioactive waste. The purpose is to do.

In order to achieve the above object, an air blast cutting apparatus according to the present invention, as described in claim 1, is an injection mechanism configured such that a granular material is injected together with compressed air through an injection nozzle; The injection nozzle is configured to be rotated or rotated around an axis extending in a position substantially parallel to the injection direction and separated from the material axis of the injection nozzle, and to be advanced along the material axis of the injection nozzle. in Rukoto a drive mechanism, in which the surface of the cutting object along a circle centered on the said axis so that the annular cutting groove is formed on the cutting object while being cut .

  The air blast cutting device according to the present invention may be configured such that the drive mechanism includes a rotating shaft disposed along the axis, a turning arm connected to the rotating shaft, and a tip attached to the tip of the turning arm. The nozzle or the injection nozzle is composed of a feed mechanism that holds the rod attached to the tip thereof so as to be capable of moving forward.

  Moreover, the air blast cutting device according to the present invention comprises the rod as a hollow tube, the blast material supply hose to which the granular material is supplied, and the compressed air supply hose to which the compressed air is supplied. And connected to the injection nozzle in a state of being inserted into the internal space.

  Further, the air blast cutting device according to the present invention includes a blast material supply hose in which the jet nozzle is formed at the distal end side and the granular material is supplied to the proximal end side, and the compressed air is supplied with the compressed air. It consists of a hollow rod-shaped injection nozzle connected to a supply hose.

  The air blast cutting device according to the present invention includes a discharge mechanism capable of sucking cutting waste through a suction tube and a suction tube feed mechanism for holding the suction tube so as to be movable forward in the ejection direction. It is.

  In the air blast cutting device according to the present invention, the granular material is dry ice.

  Moreover, the air blast cutting device which concerns on this invention makes the cutting object by the injection of the said granular material and the said compressed air the buffer material by which the overpack formed by enclosing high level radioactive waste was embedded. .

  In the air blast cutting apparatus according to the present invention, the injection nozzle can be rotated or rotated about an axis extending in a position substantially parallel to the injection direction and separated from the material axis of the injection nozzle and can be advanced in the injection direction. When the cutting object is cut, the driving mechanism is positioned so that the above-mentioned axis is substantially perpendicular to the surface of the cutting object. While rotating or rotating the nozzle around the above-mentioned axis, the granular material is injected from the injection nozzle together with the compressed air.

  If it does in this way, the granular material and compressed air which were injected from the injection nozzle will cut the surface of a cutting target object along the circle centering on the above-mentioned axis line, and will form an annular cutting groove in the cutting target object. .

  Therefore, if the injection nozzle is appropriately advanced in the injection direction so as to dig down the bottom surface of the cutting groove, the object to be cut expands to a cylindrical region (hereinafter referred to as an inner region) that extends inside the annular cutting groove and to the outside. Divided into regions (hereinafter referred to as outer regions).

  Therefore, by taking out only the inner region while leaving the outer region described above, the recovered object embedded in the cutting object can be recovered from the cutting object without receiving any shear adhesion force.

  As long as the drive mechanism can rotate or rotate around the axis and advance in the injection direction, the configuration thereof is arbitrary, and the drive force may be performed by a motor or manually, for example, A rotating shaft arranged along the above-mentioned axis, a swivel arm connected to the rotating shaft, and a spray nozzle attached to the tip of the swivel arm or a rod attached to the tip of the swivel arm are held forward. The structure comprised with the feed mechanism to perform can be employ | adopted.

  The above-described rotating shaft may be connected to the rotating shaft of the electric motor via a speed reducer, or may be connected to a rotation operation handle.

  As described above, the feed mechanism may be configured to hold the injection nozzle or the rod attached to the tip of the injection nozzle so as to be able to advance, but the injection nozzle may be configured to hold the rod attached to the tip of the advancement freely. In the case of the above configuration, cutting can be performed even when the cutting groove is deep, by appropriately adjusting the length of the rod.

  Here, for example, when the injection nozzle is attached to the tip of the rod via a bracket, there is interference between the bracket and the cutting groove, or interference between the compressed air supply hose extending from the injection nozzle or the granular material supply hose and the cutting groove. In order to avoid this, it is necessary to increase the width of the cutting groove. However, the rod is composed of a hollow tube, and the blast material supply hose to which the granular material is supplied and the compressed air supply to which the compressed air is supplied If the hose is configured to be connected to the injection nozzle while being inserted into the internal space of the rod, the blast material supply hose and the compressed air supply hose are accommodated in the internal space of the rod. There is no risk of interference.

  Further, instead of the above configuration, the injection nozzle is connected to a blast material supply hose in which a jet outlet is formed on the distal end side and a granular material is supplied to the proximal end side, and a compressed air supply hose to which compressed air is supplied It is possible to adopt a configuration in which the hollow rod-shaped injection nozzle is configured to be held forward by a feed mechanism, and the length of the hollow rod-shaped injection nozzle can be adopted. As the cutting groove is deep, cutting is possible and the compressed air supply hose and the dry ice supply hose are connected to the base end side of the hollow rod-shaped injection nozzle. There is no risk of interference with the cutting groove.

  In these configurations, a configuration is provided in which a rack gear along the axial direction of each rod is attached to each peripheral surface of a rod or a hollow rod-shaped injection nozzle, and a motor having a pinion gear that meshes with the rack gear is provided in the feed mechanism. According to this configuration, the rod or the hollow rod-shaped injection nozzle can be advanced by operating the motor of the feed mechanism.

  The cutting waste generated when cutting the object to be cut may be appropriately discharged from the annular cutting groove. For example, the surface of the object to be cut is covered with an airtight cover, and an exhaust pump is connected to the internal space of the airtight cover. This can be realized by a connection structure, but if it has a discharge mechanism capable of sucking cutting scraps through the suction pipe and a suction pipe feed mechanism for holding the suction pipe in a forward direction in the spraying direction of the spray nozzle. For example, the tip of the suction pipe can always be positioned in the vicinity of the bottom surface of the cutting groove by advancing the suction pipe as the cutting groove is dug down, so that the cutting waste can be discharged smoothly.

  The suction pipe feeding mechanism may be a mechanism different from the above-described feeding mechanism. For example, the above-mentioned feeding mechanism is configured so that the suction pipe can be held forward together with the injection nozzle or the rod so as to be a dual-purpose mechanism. It is also possible.

  As long as the granular material is capable of cutting the cutting object by being injected onto the cutting object together with the compressed air, the material, form, size, etc. are arbitrary, and are appropriately selected from known blasting materials such as sand. Although it can be selected, when this is dry ice, it is not necessary to separate the blast material from the cutting waste after cutting.

  The air blast cutting apparatus according to the present invention can be applied to all cases where a predetermined recovery object is taken out from an embedded cutting object. However, the cutting object is filled with high-level radioactive waste. A typical example is a buffer material having an overpack embedded therein.

The schematic block diagram of the air blast cutting apparatus 1 which concerns on this embodiment. Explanatory drawing which showed a mode that the overpack 21 embed | buried under the shock absorbing material 22 using the air blast cutting device 1 was collect | recovered. Explanatory drawing which showed a mode that the overpack 21 was collect | recovered continuously. The schematic block diagram which showed the air blast cutting apparatus which concerns on a modification. The schematic block diagram which showed the air blast cutting apparatus which concerns on another modification.

  Embodiments of an air blast cutting apparatus according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a view showing an air blast cutting apparatus according to the present embodiment. As shown in the figure, an air blast cutting apparatus 1 according to this embodiment is parallel to an injection mechanism 3 that injects dry ice as a granular material together with compressed air via an injection nozzle 2 and an injection direction of the injection nozzle 2. And a drive mechanism 4 that holds the injection nozzle so that the injection nozzle 2 can rotate around the axis 9 extending away from the material axis of the injection nozzle and can advance and retreat in the injection direction. It is configured.

  The injection mechanism 3 includes a dry ice supply machine 5 for producing and supplying dry ice and a compressor 6 for supplying compressed air, and the dry ice supply machine 5 is connected via a dry ice supply hose 7 as a blast material supply hose. By connecting to the injection nozzle 2 and connecting the compressor 6 to the injection nozzle 2 via the compressed air supply hose 8, it is possible to inject dry ice together with the compressed air from the injection nozzle.

  The drive mechanism 4 is attached to the rotary shaft 10 disposed along the axis 9, the motor 11 connected to one end of the rotary shaft, the turning arm 12 connected to the other end, and the tip of the turning arm. The feed mechanism 13 is generally configured. A reduction gear (not shown) may be appropriately interposed between the motor 11 and the rotary shaft 10 as necessary.

  Here, the injection nozzle 2 is attached to the tip of a rod 14 formed of a hollow tube, and the feed mechanism 13 is configured to hold the rod 14 so as to be movable forward and backward, and the dry ice supply hose 7 and The compressed air supply hose 8 is connected to the injection nozzle 2 while being inserted into the internal space of the rod 14.

  The feed mechanism 13 has, for example, a rack gear (not shown) attached to the peripheral surface of the rod 14 along the material axis direction, and a motor (not shown) in which a pinion gear meshing with the rack gear is attached to the rotating shaft. Can be configured.

  What is necessary is just to set the length of the rod 14 suitably according to the depth of the cutting groove formed in a cutting target object by injection of dry ice and compressed air.

  2 and 3 show an overpack 21 embedded in the cushioning material 22 by cutting the cushioning material 22 made of bentonite with the air blast cutting device 1 according to the present embodiment. It shows how to collect the.

  In order to collect the overpack 21 using the air blast cutting device 1 according to the present embodiment, first, as shown in FIG. 2, the drive mechanism 4 is moved so that the axis 9 is substantially perpendicular to the surface of the cushioning material 22. In addition to positioning, the rod 14 is moved forward or backward by appropriately operating the feed mechanism 13 so that the rod 14 is held by the feed mechanism 13 in the vicinity of the lower end thereof.

  Next, the dry ice supply machine 5 and the compressor 6 are operated while rotating the spray nozzle 2 around the axis 9 by operating the motor 11 to spray dry ice together with the compressed air from the spray nozzle 2.

  In this way, dry ice and compressed air injected from the injection nozzle 2 cut the surface of the cushioning material 22 along a circle centered on the axis 9, and the cushioning material 22 has an annular cutting groove 23. Since it is formed, the bottom of the cutting groove 23 is dug down by further operating the feed mechanism 13 to advance the rod 14 and consequently the injection nozzle 2 attached to the tip thereof.

  In this way, as shown in FIG. 3, the cushioning material 22 is divided into a cylindrical inner region 24 that extends inside the annular cutting groove 23 and an outer region 25 that extends outward.

  When the motor 11 and the feed mechanism 13 are operated, the motor 11 is operated so that, for example, the swivel arm 12 is reversed every 360 ° so that the bottom surface of the cutting groove 23 is dug down evenly in the circumferential direction. What is necessary is just to operate the feed mechanism 13 so that the rod 14 moves forward at the time of reversal.

  When the bottom surface of the cutting groove 23 reaches the edge cutting layer 26 provided in the vicinity of the bottom portion of the overpack 21, the cutting of the cushioning material 22 is finished.

  The edge cutting layer 26 is embedded in the cushioning material 22 in advance when the overpack 21 is installed so that the tensile force due to the adhesion of the cushioning material 22 does not act on the bottom of the overpack 21 when the overpack 21 is pulled up. It can be composed of sand or steel plate.

  Next, the overpack 21 embedded in the cushioning material 22 is recovered by taking out only the inner region 24 while leaving the outer region 25.

  As described above, according to the air blast cutting apparatus 1 according to the present embodiment, the dry ice and the compressed air injected from the injection nozzle 2 are applied to the surface of the cushioning material 22 along the circle centered on the axis 9. Since the annular cutting groove 23 is formed in the shock absorbing material 22 by cutting, the shock absorbing material 22 is made to advance in the injection direction as appropriate, and the bottom surface of the cutting groove 23 is dug down, so that the shock absorbing material 22 is made into a cylindrical inner region. 24 and the outer region 25 extending outside thereof, and by taking out only the inner region 24 while leaving the outer region 25, the overpack 21 embedded in the cushioning material 22 has no shear adhesive force. It becomes possible to collect | recover from this buffer material, without receiving.

  In addition, according to the air blast cutting device 1 according to the present embodiment, since the injection nozzle 2 is attached to the tip of the rod 14 and the feed mechanism 13 is configured so that the rod can be moved forward and backward, the rod 14 By appropriately adjusting the length, cutting can be performed even when the cutting groove 23 is deep.

  Moreover, according to the air blast cutting apparatus 1 which concerns on this embodiment, while comprising the rod 14 with a hollow tube, the dry ice supply hose 7 and the compressed air supply hose 8 are inserted in the internal space of the rod 14. Therefore, there is no possibility that the dry ice supply hose 7 or the compressed air supply hose 8 interferes with the cutting groove 23.

  Moreover, according to the air blast cutting apparatus 1 which concerns on this embodiment, since the granular material which is a blast material was made into dry ice, after cutting the buffer material 22, it is not necessary to carry out the separation process of the blast material from the cutting waste.

  In the present embodiment, in forming the annular cutting groove 23, the motor 11 is rotated so that the turning arm 12 turns in the opposite direction every 360 °, and the feed mechanism is moved so that the rod 14 moves forward when the turning is reversed. However, the method for forming the cutting groove 23 is arbitrary, and the dry ice supply hose 7 and the compressed air supply hose 8 are connected to each other via a water swivel or a similar fluid connection structure. If connected to the injection nozzle 2, the feed mechanism 13 is rotated so that the rod 14 moves forward at a constant speed while rotating the motor 11 in one direction to rotate the rotating arm 12 clockwise or counterclockwise without being reversed. May be activated.

  Further, in this embodiment, only one turning arm 12 is attached to the rotating shaft 10, but instead, for example, three turning arms 12 are attached to the rotating shaft 10 at intervals of 120 °, The feed mechanism 13, the rod 14 and the injection nozzle 2 are installed at the tip of the swivel arm, respectively, and the motor 11 is rotated so that the swivel arm 12 turns in the reverse direction every 120 °. The feeding mechanism 13 may be configured to operate as described above.

  In this embodiment, the turning arm 12 is turned by the driving force of the motor 11, but in some cases, the operation handle is connected to the rotary shaft 10 instead of the motor 11, and the operator turns the operation handle. Thus, the turning arm 12 may be turned. The feed mechanism 13 is the same, and a handle for raising and lowering the rod 14 may be provided in place of the motor built in the feed mechanism.

  In this embodiment, the injection nozzle 2 is attached to the tip of the rod 14, and the rod is advanced and retracted by the feed mechanism 13, but instead of this, as shown in FIG. Is configured with a hollow rod-shaped injection nozzle 41, and the feed mechanism 13 is configured so that the hollow rod-shaped injection nozzle can be moved forward and backward, and the hollow rod-shaped injection nozzle 41 is formed with an ejection port 42 at the tip side. The dry ice supply hose 7 and the compressed air supply hose 8 can be connected to the base end side.

  Even in such a configuration, as in the above-described embodiment, the length of the hollow rod-shaped injection nozzle 41 is appropriately adjusted so that cutting is possible even when the cutting groove is deep, and the dry ice supply hose 7 and compressed air are used. Since the supply hose 8 is connected to the base end side of the hollow rod-shaped injection nozzle 41, there is no possibility that each hose interferes with the cutting groove 23.

  In the present embodiment, the description has been made on the assumption that the edge cutting layer 26 is provided in the vicinity of the bottom of the overpack 21, but the edge cutting layer 26 may not be provided in some cases. Also in this case, the shear adhesive force from the buffer material 22 does not act on the peripheral surface of the overpack 21, and therefore the overpack 21 can be easily pulled up, as in the above-described embodiment.

  Although not particularly mentioned in the present embodiment, as shown in FIG. 5, the suction pipe 51 and an exhaust pump 52 connected to the suction pipe are connected to each other, and cutting waste can be sucked through the suction pipe. In addition to the discharge mechanism 53 configured as described above, the suction pipe feeding mechanism 54 that holds the suction pipe 51 so as to freely advance and retract in the injection direction of the injection nozzle 2 can be provided.

  As with the feed mechanism 13, the suction pipe feed mechanism 54 has, for example, a rack gear (not shown) attached to the peripheral surface of the suction pipe 51 along the material axis direction, and a pinion gear meshing with the rack gear is used as a rotation shaft. It can be set as the structure which incorporated the motor (not shown) attached.

  The suction pipe feeding mechanism 54 may be attached to the rotary shaft 10 via, for example, a revolving arm 55 extending on the opposite side of the revolving arm 12, that is, at an angular position 180 degrees away from the revolving arm.

  According to the discharge mechanism 53 described above, the tip of the suction pipe can be always positioned near the bottom surface of the cutting groove 23 by advancing the suction pipe 51 as the cutting groove 23 is dug down. It becomes possible to discharge smoothly.

DESCRIPTION OF SYMBOLS 1 Air blast cutting device 2 Injection nozzle 3 Injection mechanism 4 Drive mechanism 7 Dry ice supply hose (blast material supply hose)
8 Compressed air supply hose 9 Axis 10 Rotating shaft 12 Swivel arm 13 Feed mechanism 14 Rod 21 Overpack 22 Buffer material (cutting object)
23 Cutting groove 41 Hollow rod-shaped injection nozzle 42 Outlet 51 Suction tube 53 Discharge mechanism 54 Suction tube feed mechanism

Claims (7)

An injection mechanism configured to inject the granular material together with the compressed air through the injection nozzle, and an axis extending to the position where the injection nozzle is substantially parallel to the injection direction and separated from the material axis of the injection nozzle. in Rukoto is rotated or pivoted in around a along said timber axis of the injection nozzle is configured to be forward comprising the drive mechanism, the surface of the cutting object along a circle centered on the said axis An air blast cutting device characterized in that an annular cutting groove is formed in the object to be cut while being cut. The drive mechanism includes a rotary shaft arranged along the axis, a swing arm connected to the rotary shaft, and a nozzle attached to the tip of the swing arm or the jet nozzle attached to the tip. The air blast cutting apparatus according to claim 1, wherein the air blast cutting apparatus is configured with a feed mechanism that holds the head in a freely movable manner. The injection nozzle is configured such that the rod is formed of a hollow tube, and the blast material supply hose to which the granular material is supplied and the compressed air supply hose to which the compressed air is supplied are inserted into the internal space of the rod. The air blast cutting apparatus according to claim 2, which is connected to the air blast machine. A hollow rod-shaped injection nozzle in which the injection nozzle is connected to a blast material supply hose in which an outlet is formed on the distal end side and the granular material is supplied to the proximal end side, and a compressed air supply hose to which the compressed air is supplied The air blast cutting device according to claim 2, comprising: 5. The suction pipe feeding mechanism according to claim 2, further comprising a discharge mechanism capable of sucking the cutting waste through the suction pipe, and a suction pipe feed mechanism for holding the suction pipe forward in the ejection direction. Air blast cutting device. The air blast cutting device according to any one of claims 1 to 5, wherein the granular material is dry ice. The air blast according to any one of claims 1 to 6, wherein the granular material and the object to be cut by the jet of compressed air are buffer materials embedded with an overpack in which high-level radioactive waste is enclosed. Cutting equipment.

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