JP2010160160A - Radioactive material storage building, and ventilation method in radioactive material storage building - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radioactive material storage building and a ventilation method in the radioactive material storage building, performing efficiently natural ventilation in the building, and improving workability and earthquake resistance. <P>SOLUTION: This radioactive material storage building 1 is provided with: a building body 20 arranged over a foundation 10 provided on the ground G, for storing a radioactive material A stored in a cask 41; and a base-isolation device 30 arranged between the foundation 10 and the building body 20. An underfloor space X for circulating the outside air to the underfloor space is formed between foundation concrete 11 of the foundation 10 and a floor board 211 of the building body 20 by a receiving base part 11 of the foundation 10 and the base-isolation device 30. An air introduction port 215 for introducing the outside air into the building body 20 through the underfloor space X is formed in the floor board 211. An air discharge port 212A for discharging the air in the building body 20 to the outside is formed in an upper part of the building body 20. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a radioactive substance storage building and a ventilation method in the radioactive substance storage building.

  It is planned to store spent nuclear fuel generated at nuclear power plants in an intermediate storage facility until it is brought into a reprocessing plant and reprocessed. Since this spent nuclear fuel contains radioactive substances and has a large impact on the environment, it is stored in a cylindrical cask as a storage container with high sealing performance and excellent radiation shielding properties. Stored in an intermediate storage facility. Since spent nuclear fuel generates high heat, a natural ventilation structure is provided to take outside air into the intermediate storage facility and discharge this outside air to the outside of the intermediate storage facility to cool the spent nuclear fuel ( For example, see Patent Document 1).

As such a natural ventilation structure of the intermediate storage facility, for example, a natural ventilation structure of the intermediate storage facility 100 of radioactive material as shown in FIG. 7 is known.
As shown in FIG. 7, the radioactive substance intermediate storage facility 100 includes a foundation 110 as a direct foundation provided directly on the ground G, and a building body 120 provided on the foundation 110. However, when the ground G is soft ground, a pile foundation is used.
The building body 120 is a box-shaped building that stores spent nuclear fuel A stored in a cylindrical cask 101 for a long period of time, and includes an outer wall 102 and a ceiling 103.
At a position near the ceiling 103 of the outer wall 102, an air discharge port 102A for discharging the air in the building main body 120 to the outside is formed. In addition, an air inlet 102 </ b> B for introducing outside air into the building main body 120 is formed in the lower portion of the outer wall 102.
On the other hand, an inner wall 104 that covers the air inlet 102B along the outer wall 102 is formed on the inner side of the outer wall 102 with a predetermined space B from the outer wall 102. An opening 105 is formed at the lower end of the inner wall 104.

For this reason, as shown by an arrow Z in FIG. 7, the outside air for heat removal outside the building main body 120 flows into the space B between the outer wall 102 and the inner wall 104 via the air inlet 102B, and then the opening 105 It flows into the building main body 120 via. The air that has flowed into the building main body 120 flows toward the ceiling 103 in the building main body 120 and is discharged out of the building main body 120 through the air discharge port 102A. With such a structure, natural ventilation of the cask 101 and shielding of radiation are performed.
Japanese Patent Laid-Open No. 9-1113679

  However, such an intermediate storage facility has a problem that since the wall body has a double structure of an inner wall and an outer wall, the structure of the wall body is complicated and workability is not good. Moreover, since the air inlet which is an opening is formed on the lower side of the outer wall, there is a problem that the rigidity of the outer wall is low and the earthquake resistance of the intermediate storage facility is not good.

  The objective of this invention is providing the ventilation method in the radioactive substance storage building which can perform natural ventilation in a building efficiently, and can improve workability | operativity and earthquake resistance, and a radioactive substance storage building.

  The present invention is a radioactive material storage building for storing radioactive material, and has a floor plate supported spaced apart upward from the foundation, and an outer wall for shielding radioactivity, and the floor plate includes: An air inlet for introducing outside air into the building through the underfloor space with the foundation is provided, and air for discharging the air inside the building to the outside is provided above the building. A discharge port is provided.

  Here, as the foundation, for example, a direct foundation or a foundation using a pile foundation in combination with the direct foundation can be employed. Moreover, as a floor board, the thing made from concrete, etc. can be employ | adopted, for example, In this case, the thing which introduce | transduced the prestress for the deterioration prevention and strength improvement of the crack etc. of a floor board can also be employ | adopted. Moreover, as a radioactive substance, what is contained in a spent nuclear fuel, what is contained in another nuclear fuel, etc. can be considered.

  According to the present invention, the outside air flowing in the underfloor space is introduced into the building through the air inlet formed in the floor board, and the introduced air removes heat from the container in which the radioactive substance is stored. However, it flows upward in the building and is discharged out of the building through an air outlet formed in the upper part of the building. For this reason, the natural ventilation in a building can be performed and, thereby, a radioactive substance can fully be cooled.

Further, since the air inlet is formed in the floor board of the building, it is not necessary to form an air inlet that is an opening at the wall position facing the side surface portion of the container. Therefore, radiation that may be emitted from the container. Can be reliably shielded. Therefore, since sufficient shielding properties can be ensured in this way, it is not necessary to adopt a conventional double wall structure for the wall constituting the building, so the workability of the wall can be improved and the wall material Can be reduced.
Furthermore, since the air discharge port is formed in the upper part of the building, the rigidity of the outer wall constituting the building can be increased, and the earthquake resistance of the storage building can be improved.

In the above radioactive substance storage building, the floor board may be supported above the foundation via a seismic isolation device.
Here, as a seismic isolation device, various systems, such as what contains various elastic bodies, such as lamination rubber, a coil spring, and an air spring, and a thing using an oil damper, are employable, for example.
When such a seismic isolation device is adopted, the earthquake resistance of the storage building can be further improved. For this reason, the container stored in the storage building can be reliably prevented from overturning, and the input of high vibration components from the ground can be suppressed. It can be improved.

In the above radioactive material storage building, it is arranged on the ceiling inside the building, and has a transportation means for suspending and transporting a container in which the radioactive material is stored, and the air discharge port is located above the outer wall or The structure provided in the protrusion part which protrudes upwards from the ceiling part of the said building is employable.
With such a configuration, the container can be transported to an arbitrary position in the storage building by the transportation means arranged on the ceiling, so that the space in the storage building can be used efficiently and the heat removal efficiency can be further improved. The arrangement of the containers can be increased.

In the radioactive substance storage building, the air discharge port includes a conveying means for conveying a container storing the radioactive substance along a floor surface, and a protruding part protruding upward from a ceiling part of the building. Can be configured to be provided in the protruding portion.
Here, as this transportation means, it is generally called an air pallet or the like, and a device capable of transporting the pallet along the floor board upper surface by forming a thin air layer between the floor surface and the like can be adopted. With such a configuration, the ceiling can be formed at a lower position as compared with the case where the carrying means is provided on the ceiling, so that the amount of building materials used can be reduced and the manufacturing cost of the building can be reduced. In addition, since the air outlet is provided in the protruding part that protrudes upward from the ceiling, a sufficient difference in height between the air inlet and the air outlet can be ensured, and natural ventilation in the building can be performed efficiently. .

The above radioactive substance storage building may be provided with an outside air introduction member that is provided along the lower surface of the floor board from the outer wall of the building and guides outside air to the air introduction port.
With such a configuration, the outside air can be reliably guided to the outside air introduction port by the outside air introduction member such as a duct, so that the stored radioactive substance can be cooled more efficiently.

  The present invention is a method for ventilating a radioactive material storage building for storing radioactive material, and is provided on the floor plate through a subfloor space between the floor plate of the building and the foundation supported upwardly from the foundation. Outside air is introduced into the building from the air inlet, and air is discharged from an air outlet provided in the upper part of the building.

  As described above, according to the radioactive substance storage building and the ventilation method in the radioactive substance storage building of the present invention, it is possible to efficiently perform natural ventilation in the building and to improve workability and earthquake resistance. .

It is sectional drawing which shows the radioactive substance storage building which concerns on 1st Embodiment of this invention. It is a top view which shows the radioactive substance storage building in the said 1st Embodiment. It is sectional drawing which shows the radioactive substance storage building which concerns on 2nd Embodiment of this invention. It is a top view which shows the radioactive substance storage building in the said 2nd Embodiment. It is sectional drawing which shows the modification of the radioactive substance storage building of the said 1st Embodiment. It is sectional drawing which shows the modification of the radioactive substance storage building of the said 2nd Embodiment. It is sectional drawing which shows the conventional radioactive substance storage building.

  Hereinafter, an embodiment of a radioactive substance storage building according to the present invention will be described with reference to the drawings. In the following embodiments, the case where the present invention is applied to an intermediate storage facility of a nuclear power plant will be described.

[First embodiment]
FIG. 1 is a cross-sectional view showing a radioactive substance storage building 1. FIG. 2 is a plan view showing the radioactive substance storage building 1 with a part of the floor surface cut away.
As shown in FIG. 1, the radioactive substance storage building 1 includes a concrete foundation 10 provided in a recess G1 excavated in the ground G, a building body 20 disposed above the foundation 10, a foundation 10 and A plurality of seismic isolation devices 30 arranged between the building main bodies 20 are provided.

  As shown in FIG. 1, the foundation 10 is formed of a plate-shaped foundation concrete 11 formed on the upper surface of the recess G <b> 1 of the ground G, and a vertical rise from the upper surface 11 </ b> A of the foundation concrete 11. And a plurality of cradle units 12 to be installed. Each base 12 is provided with a seismic isolation device 30 on which a floor plate 211 of the building body 20 is supported. Accordingly, the floor plate 211 is disposed so as to be spaced upward from the foundation concrete 11 by the height of the foundation concrete 11 and the seismic isolation device 30. In this way, the underfloor space X is formed between the floor plate 211 and the foundation concrete 11 by the cradle unit 12 and the seismic isolation device 30. The underfloor space X is configured to communicate with the outside of the building main body 20, and therefore, outside air outside the building main body 20 flows through the underfloor space X.

The seismic isolation device 30 is a device for suppressing the shaking of the building body 20 with respect to the foundation 10, and for example, various types of seismic isolation devices such as laminated rubber and oil dampers can be used.
As shown in FIG. 1, the building main body 20 includes a building main body portion 21 and an overhead crane 22 as a transportation means arranged on the ceiling portion in the building main body portion 21.

  The building body 21 has a box shape for storing a plurality of casks 41 which are storage containers in which used nuclear fuel A as a radioactive substance is stored. An outer wall 212 that stands upright and shields radiation, a ceiling material 213 that covers the inside of the building body 20, and a cover member 214 that is installed outside the outer wall 212.

The spent nuclear fuel A is generated at a nuclear power plant, stored in the building main body 21 for several decades, and then carried into a reprocessing plant for reprocessing.
The cask 41 is a concrete or steel container. As is well known, the cask 41 has a sealing mechanism for confining the spent nuclear fuel A contained therein, a shielding mechanism for shielding radiation such as gamma rays emitted from the spent nuclear fuel A, and heat generation of the spent nuclear fuel A. And a heat dissipating mechanism for effectively dissipating heat.

  As shown in FIG. 1, the floor plate 211 is arranged over the upper surfaces of the plurality of seismic isolation devices 30 and constitutes the floor surface of the building body 20. The floor plate 211 is formed with a plurality of air introduction ports 215 as openings that penetrate the front and back surfaces, and the underfloor space X and the interior of the building main body 21 communicate with each other through the air introduction ports 215. ing. For this reason, the outside air in the underfloor space X is introduced into the building main body 21 through the air inlet 215.

In the example of FIG. 2, the air introduction port 215 is formed in a gap portion between the rectangular introduction port 215 </ b> A formed in the outer peripheral portion and the substantially central portion of the floor plate 211 and the cask 41 arranged on the floor plate 211. A circular inlet 215B is provided. Note that the configuration and the opening shape of the air inlet 215 are not limited to this, and it is only necessary that the underfloor space X communicates with the building body 21.
As described above, since the floor plate 211 is provided with the air introduction ports 215 that are a large number of openings, prestress may be introduced to reinforce the floor plate 211.

As shown in FIG. 1, an air discharge port 212 </ b> A that discharges air in the building main body 21 to the outside of the building main body 21 is formed at a position in the vicinity of the ceiling material 213 of the outer wall 212.
The cover member 214 includes an entry preventing member 214A that prevents a person or the like from entering the underfloor space X and the like, and a rain protection member 214B that prevents rainwater from entering the underfloor space X.
The entry preventing member 214A is a plate-like member that is provided apart from the outer wall 212 to the outside. For this reason, an air passage Y for air circulation is formed between the outer wall 212 and the entry preventing member 214A.
The rain protection member 214B is a roof member that extends from the outer wall 212 in the outdoor direction, is formed at a position above the upper end of the entry preventing member 214A, and covers the upper side of the ventilation path Y. For this reason, the intrusion of rainwater into the ventilation path Y and consequently the underfloor space X is prevented.

  Further, since it is formed at a position higher than the upper end portion of the entry preventing member 214A, there is an air passage Y between the upper end portion of the entry preventing member 214A and the lower surface portion of the rain protection member 214B. The outside air introduction port 216 that is an opening that communicates with each other is formed. Note that a louver 217 is provided at each of the air outlet 212A and the outside air inlet 216 to prevent entry of birds and beasts.

  As shown in FIG. 1, the overhead crane 22 is installed in a space on the lower side (inside the room) of the ceiling material 213, which is a ceiling part in the building main body 21, and can be transported with the cask 41 suspended. It is a device to do.

Next, the natural ventilation structure of the radioactive substance storage building 1 will be described.
As indicated by an arrow V1 in FIG. 1, the outside air outside the radioactive substance storage building 1 reaches the underfloor space X through the air passage Y through the outside air inlet 216. The air in the underfloor space X flows into the building body 21 through the air inlet 215 formed in the floor plate 211. The air flowing into the building body 21 removes heat from the cask 41 and cools the spent nuclear fuel A. The warm air after the heat exchange rises in the building main body 21 and is discharged out of the building main body 21 through an air discharge port 212 </ b> A formed on the upper end side of the outer wall 212. Thereby, the natural ventilation structure of the radioactive substance storage building 1 is realized.

According to such 1st Embodiment, there exists an effect as shown below.
(1) As described above, the radioactive material storage building 1 is provided with a natural ventilation structure as shown by the arrow V1 in FIG. 1, and thus the spent nuclear fuel A can be sufficiently cooled.

  (2) Since the air inlet 215 is formed in the floor plate 211 of the building 1, no air inlet is formed at the wall position facing the side surface portion 41A of the cask 41. For this reason, the radiation which may be emitted from the cask 41 can be reliably shielded. Since sufficient shielding properties can be ensured in this way, it is not necessary to adopt a conventional double wall structure for the outer wall 212. Accordingly, the workability of the storage building 1 can be improved and the amount of wall material used can be reduced.

  (3) Since no opening is required in the outer wall 212, the rigidity of the outer wall 212 can be increased, and the earthquake resistance of the storage building 1 can be increased.

  (4) Since the seismic isolation device 30 is adopted, the earthquake resistance of the storage building 1 can be further improved. For this reason, since the fall of the cask 41 accommodated in the storage building 1 can be reliably prevented and the input of the high vibration component from the ground G can be suppressed, the vibration of the cask 41 and the like can be avoided. Can improve safety.

  (5) Since the seismic isolation device 30 is adopted, there is no need to worry about the site in the area where the construction is to be performed. It can be improved.

  (6) Since the overhead crane 22 which is a transportation means is adopted, the cask 41 can be transported to an arbitrary position in the storage building 1, so that the space in the storage building 1 can be used efficiently and the cooling efficiency is further improved. The arrangement of the cask 41 can be increased. Furthermore, there is an advantage that the space under the ceiling material 213 can be effectively used and the work on the floor plate 211 can be made unnecessary.

  (7) Since the cover member 214 is formed, it is possible to prevent the entry of birds and beasts and people, and to prevent rainwater from entering the underfloor space X, thereby improving the safety of the storage building 1.

[Second Embodiment]
Next, the radioactive substance storage building which concerns on 2nd Embodiment of this invention is demonstrated based on drawing. FIG. 3 is a cross-sectional view showing the radioactive substance storage building 2. FIG. 4 is a plan view showing the radioactive substance storage building 2, with a part thereof cut away. In addition, the same code | symbol is attached | subjected to the component which is the same as that of the said 1st Embodiment, or is equivalent, and description is abbreviate | omitted or simplified.

  As shown in FIG. 3, the radioactive substance storage building 2 includes a building body 60 disposed above the foundation 10 and a plurality of seismic isolation devices 30 disposed between the foundation 10 and the building body 60.

The building body 60 includes a storage unit 61 that stores the cask 41 in which the radioactive substance A is stored, and a protrusion 62 that protrudes upward from the ceiling portion of the storage unit 61.
As shown in FIGS. 3 and 4, the storage unit 61 includes a box-shaped building main body 611 that stores a plurality of casks 41, and an air pallet 612 as a transportation means arranged in the building main body 611. Prepare.

The building body 611 has substantially the same configuration as the building body 20 of the first embodiment, but at least the height dimension of the outer wall 212 is lower than that of the building body 21, The difference is that an opening 61A is formed in a substantially central portion, and that a rectangular inlet 215A is formed only in the outer peripheral portion of the floor plate 211 as shown in FIG.
Although not specifically shown, the air pallet 612 discharges compressed air, which is a fluid, to the pallet as a mounting member on which the cask 41 is mounted, and to the opposite side of the pallet on which the cask 41 is mounted. And a compressed air discharge device.
The air pallet 612 provides a thin air layer between the lower surface of the pallet and the upper surface 211A of the floor plate 211 by blowing compressed air from the compressed air discharge device between the lower surface of the pallet and the floor plate 211. The cask 41 can be transported by reducing the friction coefficient.

  The protrusion 62 is a part that collects air in the building main body 611 and is formed to extend along the longitudinal direction of the building main body 611 (the front and back surfaces in FIG. 3). The protruding portion 62 includes an outer wall 621 that is a wall body and a ceiling member 622 that covers the space in the protruding portion 62.

  As shown in FIG. 3, an air discharge port 621 </ b> A that discharges the air in the building main body 611 to the outside of the building main body 611 is formed near the lower surface of the ceiling member 622 in the outer wall 621. Accordingly, the air discharge port 621A is formed at a position above the upper surface 41A of the stored cask 41. The air outlet 621A is provided with a louver 217 for preventing the entry of birds and beasts.

Here, as shown in FIG. 3, the space in the storage part 61 and the space in the protrusion part 62 are connected via the opening 61A. Therefore, the radioactive material storage building 2 is provided with the following natural ventilation structure.
That is, as indicated by an arrow V2 in FIG. 3, outside air outside the radioactive substance storage building 2 flows into the inside of the cover member 214 through the outside air introduction port 216, passes through the ventilation path Y, and enters the underfloor space X. To reach. The air in the underfloor space X flows into the storage unit 61 through the air inlet 215 and removes heat from the cask 41. The air after heat exchange rises in the storage unit 61 and flows into the protrusion 62 through the opening 61A. Then, it discharges | emits out of the building main body 60 from the air discharge port 621A formed in the outer wall 621 of the protrusion part 62, and the natural ventilation structure of the radioactive substance storage building 2 is implement | achieved.

According to the second embodiment, in addition to the same effects as (1) to (5) and (7) in the first embodiment, there are the following effects.
(8) Since the air pallet 612 can be transported by an air layer formed between the pallet and the upper surface 211A of the floor plate 211, the transport direction can be easily determined by applying a slight driving force. Thus, the cask 41 can be easily positioned.

  (9) The air pallet 612 has a relatively simple structure that only blows compressed air, and the equipment itself can be made small. For this reason, compared with the case where an overhead crane is employ | adopted like the said 1st Embodiment, the space under a ceiling can be made small and the manufacturing cost of the storage building 1 can be reduced.

  (10) Since the air pallet 612 for transporting the cask 41 along the floor surface is adopted as the transport means, the ceiling material 622 can be formed at a lower position than the case where the transport means is provided on the ceiling material 622 side. The manufacturing cost of the building 2 can be reduced by reducing the amount used. At this time, since the projecting portion 62 projecting upward from the ceiling material 622 is provided and the air exhaust port 621A is provided in the projecting portion 62, a sufficient height difference between the air introduction port 215 and the air exhaust port 621A can be secured. For this reason, natural ventilation in the building 2 can also be efficiently performed, and the radioactive material stored in the storage unit 61 can be efficiently cooled.

  (11) Moreover, by adjusting the height dimension of the protrusion part 62, the height difference between the air discharge port 621A and the air introduction port 215 can be adjusted, and ventilation efficiency can be adjusted freely.

In addition, this invention is not limited to the said embodiment, Including other structures etc. which can achieve the objective of this invention, the deformation | transformation etc. which are shown below are also contained in this invention.
FIG. 5 is a cross-sectional view of the radioactive substance storage building 3 showing a modification of the radioactive substance storage building 1. As shown in FIG. 5, the radioactive substance storage building 3 includes a duct 70 as an outside air introduction member instead of the cover member 214 of the first embodiment.
The duct 70 is a member that introduces outside air outside the building body 20 into the building body 20. The duct 70 includes a vertical duct 71 arranged in the vertical direction along the outdoor side surface of the outer wall 212, a horizontal duct 72 connected to the vertical duct 71 and arranged in the horizontal direction in the underfloor space X, and the horizontal duct 72. And an indoor connection duct 73 connected to the duct 72 and disposed at the air inlet 215. On the upper end side of the vertical duct 71, an outside air introduction port 71A is formed.

  According to the above configuration, the outside air flows in from the outside air inlet 71A of the vertical duct 71, passes through the vertical duct 71, passes through the horizontal duct 72, and passes through the indoor connecting duct 73. Flows in. Thereafter, the inflowing air is discharged out of the building body 20 through the air discharge port 212A. Since such a duct 70 is employed, outside air can be reliably guided into the building body 20.

In addition, as shown in FIG. 6, a rectifying plate 81 that is an outside air introduction member may be disposed in the underfloor space X of the radioactive substance storage building 2 to guide outside air to the air introduction port 215. In this way, outside air can be reliably guided into the building body 20, and there is an advantage that the cooling efficiency of the cask 41 can be further improved.
Moreover, in each said embodiment, although the seismic isolation apparatus 30 was employ | adopted in order to ensure underfloor space, you may support apart from the foundation 10 with columnar or wall-like concrete.

Moreover, in each said embodiment, although the air inlet 215 was formed in the outer peripheral part etc. of the floor board 211, the position to form is not specifically limited, It can form in arbitrary positions with reference to heat removal efficiency etc. At this time, the cross-sectional shape of the air inlet 215 and the number of air inlets 215 are not particularly limited.
Moreover, in each said embodiment, although the foundation was directly employ | adopted as a foundation, it is not restricted to this, For example, you may employ | adopt other foundations, such as a pile foundation. If a pile foundation is used, storage facilities can be constructed even in areas with weak ground. Moreover, since the response of a building main body can be reduced if a pile foundation and a seismic isolation apparatus are used, the freedom degree of design of a pile foundation can also be improved.

  In the first embodiment, the air discharge port 212A is formed in the vicinity of the ceiling material 213 of the outer wall 212. However, the present invention is not limited to this, and a protruding portion that protrudes upward from the ceiling portion is provided as in the second embodiment. It may be provided and an air discharge port may be formed in the protruding portion. In addition, you may form an air exhaust port in both the ceiling material side and protrusion part of an outer wall.

1,2,3 Radioactive material storage building 10,110 Foundation 21A, 102A, 212A, 621A Air discharge port 22 Overhead crane as transport means 30 Seismic isolation device 41, 101 Cask as container 62 Projection part 70 Outside air introduction member Duct 102B, 215 Air introduction port 211 Floor plate 212, 621 Outer wall 612 Air pallet as a transport means A Used nuclear fuel containing radioactive material X Underfloor space

Claims (1)

A radioactive material storage building for storing radioactive material,
A floorboard supported upwardly spaced from the foundation, and an outer wall for shielding radiation;
The floor board is provided with an air inlet for introducing outside air into the building through the underfloor space between the foundation and the floor,
A radioactive substance storage building characterized in that an air discharge port for discharging the air inside the building to the outside is provided in the upper part of the building.

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