JP2006322894A - Spent fuel storage facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spent fuel storage facility capable of compacting the storage facility by forming the storage facility provided with a container conveying means separated from structure of a building, and capable of carrying out efficient exhaust heat ventilation in an inside of the storage facility. <P>SOLUTION: The spent fuel storage facility 10 is constituted of the building 1, a conveyer 2 for conveying a cask (a) to a prescribed position while moving on a floor of the building 1. The conveyer 2 rail-travels on a plurality of rails 12 provided on the floor, and a traverser 13 is provided on the floor to be extended along a direction orthogonal to the rails 12. Rails 12a, 12b are further provided on an external conveying route 5 provided in an outside of the building 1, the conveyer 2 rail-traveling on the rails 12a, 12b carries the cask (a) into the building 1, and the cask (a) is conveyed/mounted in a proper position, by the movement of the traverser 13 and the rail-traveling of the conveyer 2 in the building on the rails 12a, 12b. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a storage facility for storing containers for storing spent fuel such as radioactive materials generated from nuclear power plants, and in particular, by providing a storage facility with container transport means separated from the structure of a building. The present invention relates to a spent fuel storage facility that can reduce the size of the storage facility and that can perform efficient exhaust heat ventilation in the storage facility.

  Spent fuel generated from nuclear power plants needs to be stored in a safe state without being released to the outside for a period until reprocessing. As a method for storing spent fuel, there are a storage method using a water pool and a dry storage method using a storage container called a steel or concrete cask. Spent fuel contained in the cask contains fission products and transuranium elements in addition to residual fuel such as uranium and plutonium, so it emits radiation and generates heat due to decay heat. Therefore, the cask must have functions such as criticality prevention, radiation shielding, cooling, and sealing.

  In the conventional dry fuel storage method, spent fuel is stored in a transport cask at a nuclear power plant, and the cask is transported to a storage facility by land or sea transport. There are a method of refilling fuel from a cask into a metal canister and storing it in a sealed state, and a method of storing a cask directly in the facility. Whichever method is applied, the conventional storage facility has a facility structure in which the transported cask or canister is transported to a predetermined placement place by an overhead crane provided in the storage facility. . For example, Patent Documents 1 and 2 disclose inventions related to spent fuel storage facilities. In any facility, a cask or canister is transported to a predetermined position of the facility by an overhead crane provided in the facility.

JP 2004-45230 A JP 2001-91683 A

  According to the spent fuel storage facility disclosed in Patent Documents 1 and 2, in order to transport the cask or canister to a predetermined position in the facility by the overhead crane, the structure of the building constituting the facility is subject to various restrictions. It will be. For example, pillars and walls cannot be constructed within the working range so as not to obstruct the traveling of the overhead crane, and therefore the flat dimensions of the building are limited. In addition, the use of the overhead crane system inevitably increases the structural members of the building frame including the ceiling, which increases the cost required for building construction. Furthermore, according to the overhead crane system, the height of the machine such as the suspension allowance and the garter height is required, and therefore, the building structure has an eave height much higher than the height of the spent fuel container. As a result, the structural members of the building frame have become large.

  The spent fuel storage facility according to the present invention has been made in view of the above-described problems, and is configured not to apply a method of transporting a cask or canister to a predetermined position in the facility by an overhead crane method. It is an object of the present invention to provide a spent fuel storage facility that can be constructed without being affected by the topography of the site. In addition, the height of the eaves of the building can be made as low as possible. Furthermore, since the construction of pillars and walls is not restricted when the cask or canister is transported in the building, the building components can be made smaller. The purpose of the present invention is to provide a spent fuel storage facility that can reduce the construction cost of the facility as compared with the conventional one.

  In order to achieve the above object, a spent fuel storage facility according to the present invention is a spent fuel storage facility for storing a containing container containing spent fuel made of a radioactive substance, and the spent fuel storage facility is a building. And a transport device for transporting the container to a predetermined position while moving on the floor constituting the building.

  The structure type of the building may be a wall structure or a ramen structure, and a conventional building for a spent fuel storage facility can be applied as it is. However, a ramen structure is preferable from the viewpoint of more effectively using the internal space of the building and increasing the degree of freedom in transporting the storage container. In the present invention, an overhead crane for transporting the storage container to the building is not provided. Therefore, not only the structural member of the building is downsized, but also its planar shape is flexible to the topography of the building construction point. It is possible to select a shape adapted to the above. Moreover, since the container is not transported by the overhead crane, the eave height of the building can be made as low as possible. The installation of the storage container at a predetermined position in the building is performed by an appropriate transfer device that moves on the floor of the building. Although embodiment of a conveying apparatus is not specifically limited, For example, a storage container can be mounted and a self-propelled cart can be used.

  By replacing the conventional overhead crane transportation system with the floor transportation system, it is possible to completely separate the building and the storage container transportation means, and therefore, as described above, to reduce the scale of the building, Since the restriction that the column cannot be constructed in the work range of the overhead crane is eliminated, it is possible to improve the degree of freedom of the building shape (planar shape or three-dimensional shape). In particular, the downsizing of the building scale leads to an increase in the possibility of constructing a spent fuel storage facility with a limited construction site.

  Further, in another embodiment of the spent fuel storage facility according to the present invention, the transfer device comprises at least an air caster which is a moving means of the device, an air supply unit, and a gripping means for gripping the storage container. It is characterized by being.

  The present invention shows an embodiment of a transfer device, for example, self-propelled, and holding means for holding containers are provided on four air casters so that stable running is possible. There is a form in which air can be supplied to an air caster from an air supply unit such as a compressor. For example, the gripping means chucks the side surface of the container at two locations.

  Since the transfer device can move freely on a flat building floor with an air caster, for example, the container can be transferred / installed at a predetermined mounting position without being affected by the position of the pillars constituting the building. It becomes possible to do.

  Moreover, in another embodiment of the spent fuel storage facility according to the present invention, the transfer device is composed of a frame body that travels in a rail or a tire in a posture in which the storage container is suspended.

  The present invention shows another embodiment of the transfer device. For example, a lifting jack is provided on the ceiling of a frame structure formed by connecting two frame frames with a horizontal member. This is a form in which the frame body freely moves in the building in a posture in which the storage container is suspended. Here, even if the moving means of the frame is a rail traveling system that travels on a rail provided on the floor of the building, it is a tire traveling system that travels with a tire (caster) provided at the lower part of the structural body. There may be.

  Further, in another embodiment of the spent fuel storage facility according to the present invention, the transfer device is a frame structure that travels in a rail or a tire in a posture in which the storage container is placed or suspended, and is separately installed on the floor. It is comprised so that it can drive | work on a floor with the attitude | position straddling the storage container of this.

  The present invention shows still another embodiment of the transfer device. For example, a jack that rolls over the container while lifting the container is mounted on the ceiling of the frame described above, and is provided at a predetermined level of the frame. The frame body travels in the building in a state in which the storage container in a posture of being lifted / rolled on the horizontal member is placed horizontally. The predetermined level of the horizontal member is at least a level equal to or higher than the height of the container so that the frame can run over a separate container placed vertically at an arbitrary position in the building. That is. In a building, since storage containers (casks and canisters) that normally store a plurality of spent fuels are arranged and placed in a row, the structure must be configured so that the frame can travel across the storage containers. Thus, even in a building in which a large number of storage containers are placed, the degree of freedom of travel of the frame can be significantly improved. In particular, it is suitable for the operation of taking out the storage container or the like placed in the back of the building.

  In another embodiment of the spent fuel storage facility according to the present invention, a plurality of rails are provided on the floor constituting the building, and a traverser is provided in a direction perpendicular to the rails, The transport device can travel along the rail, and the transport device can be moved in a direction perpendicular to the rail in a posture placed on the traverser.

  On the floor of the building, multiple sets of a set of rails composed of, for example, two rails are provided so that the storage containers can be arranged and placed, and the frame as a transport device runs on the rails on the rails. It can be configured. As described above, the frame moves on the rail in a posture in which the storage container is suspended or placed horizontally, and the storage containers are arranged and placed in the rail in order from the back of the building. The plurality of rails are provided, for example, in one direction of the building (in the case of a rectangular building in a plan view, the short direction thereof). Here, a traverser is provided in a direction orthogonal to the multiple rails (in the case of a rectangular shape in plan view and in the case where the rail extends in the short direction), the traverser is provided. This traverser is a self-propelled transport carriage provided in the floor, and a floor groove extending in a direction perpendicular to the rail is provided, and a carriage whose ceiling is at the same level as the floor surface is provided in the floor groove. It is self-propelled. By providing such a traverser on the floor, when transporting / positioning the transport device on a predetermined rail, the storage container can be moved to the end of the rail in a posture placed on the traverser, and the storage container It becomes possible to place the transporting device after placing on the traverser and transport / position to the next rail. The location and quantity of the traverser may be appropriately selected according to the plan view shape of the building, the installation status of the rails, the placement plan of the storage container, and the like.

  Further, in another embodiment of the spent fuel storage facility according to the present invention, a rail is provided so as to communicate from the outside to the inside of the building, and the transfer device travels on the rail, so that the inside from the outside of the building. The storage container is transported to the container.

  For example, in the embodiment in which the container is transported by sea and transported to the spent fuel storage facility, the rails are extended from the quay container yard to the spent fuel storage facility building, and loaded into the container yard. There is a form in which the storage container is suspended or placed on the transfer device, and the transfer device moves on the rails to carry the storage container into the building. The transport device that has entered the building is, for example, placed on the traverser described above, transported to an appropriate rail in the building, and transported / placed the container at an appropriate location by running on the rail. can do. In this way, by adopting a configuration in which the storage container is delivered outside the building, it is not necessary to provide a delivery area or delivery facility for the storage container in the building, so the building scale should be reduced as much as possible. Is possible.

  Furthermore, in another embodiment of the spent fuel storage facility according to the present invention, the ceiling constituting the building is a double ceiling in which an outer first ceiling and a second ceiling of the building interior are provided with an interval. The second ceiling is provided with an opening through which gas from the lower space can flow between the first ceiling and the second ceiling. The discharge port for discharging the gas flowing between the first ceiling and the second ceiling to the outside is provided, and is provided to the storage container placed on the floor, and the heat dissipation from the storage container The gas heated by is discharged between the first ceiling and the second ceiling through the opening, and discharged to the outside through the discharge port.

  There is a problem that it will be difficult to remove the decay heat of spent fuel by natural ventilation by reducing the size of the building of the spent fuel storage facility, especially by reducing the eave height of the building. Therefore, it is necessary to provide a gas (for example, outside air) evenly to a large number of containers arranged and placed on the floor of the building, and at that time, a method for efficiently releasing the gas warmed by the decay heat to the outside of the building is necessary. It becomes.

  Therefore, in the present invention, a double structure including two ceilings provided with a ceiling constituting the building is provided, and an opening is provided in the lower ceiling, thereby providing the structure from the lower side surface of the building. Outside air is provided to the storage container, and warmed outside air is discharged from the opening into the double-structure ceiling. The outside air discharged into the double-structure ceiling is discharged from a discharge port provided on the outside ceiling facing the outside. The discharge port may be provided with a ventilation tower, or may be provided with a fan near the discharge port for sucking outside air inside the building and releasing it outside.

  In the case of a configuration in which outside air flows from the opposite side walls of the building toward the center of the building, the opening provided in the ceiling is in the form of a slit parallel to the extending direction of the side wall near the center of the ceiling. It is preferable. In this case, by providing a slit-like discharge port on the ceiling on the opposite side wall, the outside air flowing into the double-structured ceiling through the slit opening is distributed to the two slit discharge ports. And efficiently discharged from both outlets to the outside.

  As can be understood from the above description, according to the spent fuel storage facility of the present invention, since the building and the container transport device are completely separated, the degree of freedom in the planar dimensions of the building is increased. Therefore, a spent fuel storage facility applied to the terrain of the site can be constructed. In addition, according to the spent fuel storage facility of the present invention, since the building and the container transport device are completely separated, the scale of the building can be reduced as much as possible, and the construction The cost can be reduced and the construction can be facilitated when constructing the facility whose construction is limited. Furthermore, according to the spent fuel storage facility of the present invention, the ceiling of the building has a double structure, and the outside air that has flowed into the building is guided to the inside of the ceiling and then released to the outside. Although the scale is reduced, the decay heat of spent fuel can be efficiently removed by natural ventilation.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an outline of an embodiment of a spent fuel storage facility according to the present invention, in which a part thereof is broken. FIG. 2 is a perspective view of an embodiment of a transfer device. FIG. 3: has each shown the perspective view which showed the traverser provided in the floor of the building. FIG. 4 is a schematic view showing the flow of outside air in the building, and FIGS. 5 and 6 are perspective views of other embodiments of the transfer device. It goes without saying that the rails and traversers provided in the building are not limited to the illustrated embodiment.

  FIG. 1 shows an outline of the spent fuel storage facility 10. The spent fuel storage facility 10 includes a building 1, a transport device 2 for transporting a cask a for storing spent fuel, and a container yard on a quay in the X direction in the figure, which is not illustrated. It is generally composed of an external conveyance path 5 that leads to the building 1. In the present embodiment, the cask is transported from the nuclear fuel facility to the seawall near the place where the spent fuel storage facility 10 is constructed by sea transportation, and the cask unloaded at the seawall is transferred via the external transport path 5. The form which conveys in the building 1 is shown. In the case of land transportation, the cask is unloaded from the trailer or the like outside the building, and is transported into the building via the same external transportation path as shown in the figure.

  A rail 12a is provided in the external transport path 5, and the cask a is carried into the building 1 while the transport device 2 in a posture in which the cask a is suspended on the rail. The conveying device 2 that has entered the building 1 is provided on the floor of the building, and is placed on a traverser 13 that extends in the longitudinal direction of the building 1 in the vicinity of the side wall 17 of the building 1. The transport device 2 is transported to the ends of the appropriate rails 12 and 12 that extend in a direction orthogonal to the traverser 13 (extends in the short direction of the building 1) as the traverser 13 moves in the longitudinal direction of the building 1. / Positioned, the transfer device 2 is moved to the rails 12 and 12, and the cask a can be transferred / placed at a predetermined position by running on the rails 12 and 12.

  The building 1 is generally composed of a floor 11, side walls 17, 17,..., And ceilings 14a, 14b that are provided in a double structure and spaced apart from each other. The double ceilings 14a and 14b are connected by a truss frame 14c, but are not limited to such a configuration. In the building 1, columns 15, 15,... For increasing the degree of freedom of the internal space and supporting the ceiling are arranged in rows at intervals. Between the pillars 15 and 15, rails 12 and 12 on which the transport device 2 travels on a rail are disposed.

  The lower ceiling 14b is provided with a slit-like opening 14b1 extending in the longitudinal direction of the building 1 at the center. On the other hand, slit-like air outlets 14a1 and 14a1 extending in the longitudinal direction of the building 1 are provided at the end of the ceiling 14a facing the outside, and a ventilation tower 16 is provided on the outlet 14a1. . A configuration in which a fan (not shown) is provided in the vicinity of the discharge port 14a1 may be employed.

  The cask a carried into the building 1 by the transport device 2 is sequentially transported / placed between the pair of rails 12 and 12 by the transport device 2 and the traverser 13.

  FIG. 2 is an enlarged view of the transfer device 2 shown in FIG. The transport device 2 is a so-called low head type transport device that does not straddle the cask a placed on the floor and has a relatively low frame height. The top ends of the two frame frames 21 and 21 that run on the rail 12 are connected by a stage 22. A jack 23 for lifting a cask a on the stage 22, A generator 24 for driving and driving the conveying device itself is mounted. By using such a low-head type conveying device 2, the eave height of the building 1 can be made as low as possible, and the construction cost of the entire building can be reduced.

  FIG. 3 is an enlarged view of the traverser 13 that self-propels in the groove 11a provided on the floor surface. The top level of the traverser 13 is configured to be the same level as the floor surface. When the traverser 13 is positioned on the appropriate rails 12 and 12, the transport device 2 is placed on the floor surface from above the traverser 13. The upper rails 12 and 12 are movable.

  FIG. 4 is a diagram schematically illustrating the flow of outside air that has flowed into the building 1. The outside air that has flowed into the building 1 from the air supply ports 17a provided in the side walls 17 and 17 extending in the longitudinal direction of the building 1 is equally supplied to the casks a, a,. (In the direction of arrow X1), flows to the side walls 17 and 17 through the slit-shaped opening 14b1 provided in the lower ceiling 14b of the double structure in the center of the building 1 (in the direction of arrow X2), and the upper ceiling facing the outside It will be discharged | emitted outside via the ventilation towers 16 and 16 through the discharge ports 14a1 and 14a1 provided in 14a (arrow X3 direction). Such a flow of outside air can be generated at any time by appropriately moving a fan or the like (not shown).

  FIG. 5 shows another embodiment of the transport device. The transfer device 3 is configured to straddle the cask a placed on the floor, and is a so-called overhead type transfer device. The top ends of the two frame frames 31, 31 traveling on the rail 12 are connected by a stage 33, and the lower members thereof are connected by horizontal members 32, 32 connecting the two frame frames 31, 31. On the stage 33, there is mounted a jack 34 that lifts the cask a and rolls over the cask a. The level of the horizontal members 32, 32 is adjusted to a level at least equal to or higher than the height of the cask a so that it can straddle the casks a, a,. By using such an overhead type transfer device 3, even when the casks a, a,... Are placed in the building 1, it is possible to take out any placement cask a. It is possible to increase the degree of freedom of movement of the transfer device.

  FIG. 6 shows still another embodiment of the transport apparatus. This transport device 4 is not a method of traveling on a rail on the floor, but is a device that freely travels on the floor with its own air-floating attitude, and has four air casters 41, 41, 41 having an air pallet on the lower surface. , 41 are connected to each other, and further, gripping members 43, 43 for gripping and fixing the cask a are provided. When the transporting device 4 moves up and down, compressed air is discharged from the lower surfaces of the air casters 41, 41,... By compressors 42, 42,. The driving source for the compressor 42 and the gripping member 43 is a generator 44 mounted on the apparatus.

  By using such an air caster type transfer device 4, it is not necessary to provide rails on the floor surface of the building 1, and the construction cost can be further reduced. Further, in order to enable proper transport / placement of the casks a, a,... On the floor surface, a distance sensor or the like (not shown) is installed in the transport device 4 so It is possible to ensure an appropriate separation when placing.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention. For example, the building and the transfer device of the present invention constitute a facility for storing a container for storing spent fuel, but not only the spent fuel storage facility but also a facility for storing any heavy objects. Is also applicable. That is, when a heavy object is transported / placed in a building, an overhead crane or the like has been conventionally used. However, by combining the building of the present invention and a transport device, the scale of the building can be reduced. It is possible to increase the degree of freedom in selecting the planar shape and the three-dimensional shape.

It is the perspective view which showed the outline | summary of one Embodiment of the spent fuel storage facility of this invention, Comprising: The figure which fractured | ruptured the part. The perspective view of one Embodiment of a conveying apparatus. The perspective view which showed the traverser provided in the floor of the building. The schematic diagram which showed the flow of the external air in a building. The perspective view of other embodiment of a conveying apparatus. The perspective view of other embodiment of a conveying apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Building, 11 ... Floor, 12, 12a ... Rail, 13 ... Traverser, 14a, 14b ... Ceiling, 14a1 ... Release port, 14b1 ... Opening, 15 ... Column, 16 ... Ventilation tower, 17 ... Side wall, 2, 3, DESCRIPTION OF SYMBOLS 4 ... Conveyance apparatus, 21 ... Frame frame, 22 ... Stage, 23 ... Jack, 24 ... Generator, 31 ... Frame frame, 32 ... Horizontal material, 33 ... Stage, 34 ... Jack, 41 ... Air caster, 41a ... Air pad, 42 ... Compressor (air supply unit) 43 ... Holding member 44 ... Generator 5 ... External transport path 10 ... Spent fuel storage facility a ... Casque (container)

Claims (7)

A spent fuel storage facility for storing a containment container containing spent fuel made of radioactive material,
The spent fuel storage facility comprises at least a building and a transport device that transports the storage container to a predetermined position while moving on a floor constituting the building. .   2. The spent fuel according to claim 1, wherein the transport device includes at least an air caster that is a moving unit of the device, an air supply unit, and a gripping unit that grips the storage container. Storage facility.   2. The spent fuel storage facility according to claim 1, wherein the transport device includes a frame body that travels in a rail or a tire in a posture in which the container is suspended.   The transport device is composed of a frame body that travels in a rail or a tire in a posture in which the storage container is placed or suspended, and is configured to be able to travel on the floor in a posture straddling a separate storage container placed on the floor. The spent fuel storage facility according to claim 1, wherein:   A plurality of rails are provided on the floor constituting the building, and a traverser is provided in a direction orthogonal to the rails, and the transport device can travel along the rails, and the transport device can be a traverser. The spent fuel storage facility according to claim 3 or 4, wherein the spent fuel storage facility is configured to be movable in a direction perpendicular to the rail in a posture placed on the top.   A rail is provided so as to communicate from the outside to the inside of the building, and the container is transported from the outside to the inside of the building by running the transport device on the rail. A spent fuel storage facility according to any of the above.   The ceiling that constitutes the building has a double structure in which an outer first ceiling and a second ceiling in the building are provided with an interval, and the second ceiling has a lower space. From which the gas from the first ceiling and the second ceiling can flow is provided, and the first ceiling has a gas flowing between the first ceiling and the second ceiling. Is provided to the storage container placed on the floor, and the gas heated by heat radiation from the storage container is connected to the first ceiling through the opening. The spent fuel storage facility according to any one of claims 1 to 6, wherein the spent fuel storage facility is configured to be discharged between the second ceilings and discharged to the outside through the discharge port.

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