JP2013148434A - Radioactive material storage facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suitably prevent radiation linearly leaked from radioactive materials to the outside and to efficiently cool the radioactive materials in a radioactive material storage facility.SOLUTION: The radioactive material storage facility includes: a building 21 having a hollow shape and capable of arranging a plurality of casks 10 on its inner installation floor 12; suction ports 22a, 22b arranged on an upper part of a sidewall 14 of the building 21; exhaust ports 26a, 26b formed on a center part of a ceiling wall 13 of the building 21; and a shield plate 27 arranged in areas Sa, Sb connecting the plurality of casks 10 arranged on the installation floor 12 to the exhaust ports 26a, 26b.

Description

  The present invention relates to a radioactive material storage facility for storing radioactive materials such as spent nuclear fuel after combustion.

  As one of nuclear power plants, for example, there is a pressurized water reactor. In this pressurized water reactor, light water is used as a reactor coolant and a neutron moderator, and high-temperature and high-pressure water that does not boil throughout the primary system is used. High-temperature high-pressure water is sent to a steam generator to generate steam by heat exchange, and this steam is sent to a turbine generator for power generation.

  At the end of the nuclear fuel cycle, nuclear fuel assemblies (spent nuclear fuel) that have become unusable after combustion have been installed in nuclear power plants because they contain highly radioactive materials and need to be cooled thermally. The cooling pool is cooled for a predetermined period. Thereafter, when the spent nuclear fuel is cooled to a predetermined temperature or lower, it is stored in a cask that is a radioactive substance storage container, transported to a radioactive substance storage facility by a truck or the like, and stored in a cooled state for a long period of time.

  Examples of such a radioactive substance storage facility are described in the following patent documents. The radioactive waste storage described in Patent Document 1 is capable of arranging a plurality of articles to be stored in a storage building, forming an outside air intake at the outer periphery, and providing an exhaust at the top. In addition, the cask storage facility described in Patent Document 2 allows a plurality of casks to be arranged inside the tower, forms an outside air inlet at the lower outer periphery, forms a ceiling opening at the upper outer periphery, and uppers above the cask. A shielding wall is arranged. In addition, the cask storage facility described in Patent Document 3 is configured such that a plurality of casks can be arranged in the storage chamber, an intake port and an exhaust port are formed in the upper outer periphery, and the intake port and the storage chamber are connected by an intake duct. is there.

No. 07-049440 Japanese Patent Publication No. 04-44958 Japanese Patent No. 3881545

  Although the cask has a neutron shield on the outer periphery of the trunk body to prevent radiation leakage, a small amount of radiation is emitted, and the radioactive substance storage facility stores multiple casks while cooling them. In addition, it is necessary to devise so that radiation does not leak outside the facility during storage. In the conventional radioactive material storage facility described above, the position is devised so that radiation does not come out of the cask from the intake and exhaust ports, but the circulation of the air flowing inside becomes insufficient, There exists a problem that the cooling efficiency of a cask will fall.

  This invention solves the subject mentioned above, and provides the storage facility of the radioactive substance which can cool a radioactive substance efficiently while preventing the radiation which leaks linearly from a radioactive substance to the exterior appropriately. Objective.

  In order to achieve the above object, the radioactive substance storage facility of the present invention comprises a building having a hollow shape and capable of arranging the radioactive substance on the inner floor surface, and at least the side walls and the ceiling having a radiation shielding function, An air inlet provided in the upper part of the side wall in the building, an air outlet provided in the center of the ceiling in the building, and a shielding plate provided in a region connecting the radioactive substance disposed on the floor and the air outlet, It is characterized by providing.

  Therefore, by providing a shielding plate in the area connecting the radioactive material arranged on the floor and the exhaust port, the radiation from the radioactive material is shielded by the shielding plate, so that the radioactive material passes through the exhaust port to the outside. Radiation that leaks linearly to the outside can be properly prevented, and an air inlet is provided in the upper part of the side wall, while an air outlet is provided in the center of the ceiling, so that the outside air that has entered from the air inlet is radioactive inside the building. After the substance is cooled, the substance is discharged from the exhaust port, and the radioactive substance can be efficiently cooled by arranging the radioactive substance in the outside air passage.

  In the radioactive substance storage facility according to the present invention, the side wall includes first and second side walls that face each other, and first and second air inlets are provided on top of the first and second side walls, respectively. First and second air intake ducts are provided to communicate the first and second air inlets with the floor side of the building.

  Accordingly, the first and second intake ports provided on the upper portions of the first and second side walls communicate with the floor side of the building through the intake duct, so that the outside air that has entered from the first and second intake ports is The air flows through the first and second air intake ducts to the floor of the building, and the radioactive material arranged here is cooled down reliably and then discharged from the exhaust port, thereby improving the cooling efficiency of the radioactive material. it can.

  In the radioactive substance storage facility of the present invention, the building is characterized in that first and second radioactive substance arrangement regions are provided on the floor surface adjacent to the first and second side walls with an intermediate portion therebetween. .

  Therefore, by providing the first and second radioactive substance arrangement areas on the first and second side walls with the intermediate part opened, the radioactive substances in each radioactive substance arrangement area are arranged efficiently and the cooling efficiency of the radioactive substance is improved. can do.

  In the radioactive substance storage facility of the present invention, the shielding plate includes a first shielding plate provided in a region connecting the radioactive material arranged in the first radioactive material arrangement region and the exhaust port, and the second radioactive material. It has the 2nd shielding board provided in the area | region which connects the said radioactive substance arrange | positioned in a substance arrangement | positioning area | region, and the said exhaust port.

  Therefore, by providing the first shielding plate corresponding to the first radioactive substance arrangement region and the second shielding plate corresponding to the second radioactive substance arrangement region, the internal air is efficiently made with the space between the first and second shielding plates as a space portion. Can be led to the exhaust port.

  In the radioactive substance storage facility of the present invention, the first and second shielding plates are each composed of an upper shielding plate and a lower shielding plate which are divided into upper and lower parts.

  Therefore, by dividing the first and second shielding plates into the upper shielding plate and the lower shielding plate, the shielding area is reduced, and the manufacturing cost can be reduced.

  In the radioactive substance storage facility of the present invention, a non-radioactive substance arrangement area where the radioactive substance is not arranged is provided between the first and second radioactive substance arrangement areas, and the non-radioactive substance arrangement area and the exhaust port are provided. A cooling air passage is provided so as to be connected.

  Therefore, by providing the cooling air passage that communicates from the non-radioactive material arrangement region to the exhaust port, the air in the vicinity of the radioactive material can be efficiently guided to the exhaust port.

  The radioactive substance storage facility according to the present invention is characterized in that the floor of the building is provided with a step portion on which the exhaust port side is higher than the intake port side and on which the radioactive substance can be arranged.

  Therefore, by providing the step portion on which the radioactive substance can be arranged, the shielding area is reduced, and the manufacturing cost can be reduced.

  According to the radioactive substance storage facility of the present invention, an air inlet is provided in the upper part of the side wall of the building, an exhaust port is provided in the center of the ceiling of the building, and the region connecting the radioactive substance arranged on the floor and the exhaust port is provided. Since the shielding plate is provided on the surface, radiation that leaks linearly from the radioactive substance to the outside can be prevented appropriately, and the radioactive substance can be efficiently cooled.

FIG. 1 is a longitudinal sectional view showing an internal structure of a radioactive substance storage facility according to Embodiment 1 of the present invention. FIG. 2 is a horizontal sectional view showing the internal structure of the radioactive substance storage facility according to the first embodiment. FIG. 3 is a longitudinal sectional view showing the flow of cooling air in the radioactive substance storage facility according to the first embodiment. FIG. 4 is a perspective view illustrating the radioactive substance storage facility according to the first embodiment. FIG. 5 is a longitudinal sectional view showing the internal structure of the radioactive substance storage facility according to the second embodiment of the present invention. FIG. 6 is a longitudinal sectional view showing the internal structure of a radioactive substance storage facility according to Example 3 of the present invention. FIG. 7 is a longitudinal sectional view showing a flow of cooling air in the radioactive substance storage facility according to the third embodiment. FIG. 8 is a longitudinal sectional view showing the internal structure of a radioactive substance storage facility according to Embodiment 4 of the present invention.

  Exemplary embodiments of a radioactive substance storage facility according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example, Moreover, when there exists multiple Example, what comprises combining each Example is also included.

  FIG. 1 is a longitudinal sectional view showing the internal structure of a radioactive substance storage facility according to Embodiment 1 of the present invention, and FIG. 2 is a horizontal sectional view showing the internal structure of the radioactive substance storage facility according to Embodiment 1. These are the longitudinal cross-sectional views showing the flow of the cooling air in the radioactive substance storage facility of Example 1, and FIG. 4 is the perspective view showing the radioactive substance storage facility of Example 1. FIG.

  In the radioactive substance storage facility according to the first embodiment, as shown in FIG. 4, the storage facility 11 is entirely constituted by a concrete wall, and has an installation floor 12, a ceiling wall 13, and a plurality of side walls 14. In the storage facility 11, a large number of casks 10 are arranged on the installation floor 12 at predetermined intervals. Each cask 10 contains an assembly (radioactive material) of spent nuclear fuel. Further, the storage facility 11 is provided with a loading pit 16 having a loading gate 15 on one side, and the cask 10 is carried into the storage facility 11 from the loading pit 16 by a carrying vehicle (not shown). . The storage facility 11 is provided with a cask transfer crane 17 in the upper portion, and the cask 10 carried into the carry-in pit 16 is transferred by the cask transfer crane 17 and arranged at a predetermined position.

  The storage facility 11 will be described in detail. As shown in FIGS. 1 and 2, the building 21 is provided with first and second side walls 14 a and 14 b facing each other on the four sides of the installation floor 12, and the first facing each other. 3, 4th side wall 14c, 14d is provided, and the ceiling wall 13 is provided in the upper end part of each side wall 14a, 14b, 14c, 14d, and is comprised. The building 21 has a hollow shape, and the installation floor 12, the ceiling wall 13, and the side walls 14 (14 a, 14 b, 14 c, 14 d) have a radiation shielding function. A plurality of caskes 10 can be arranged.

  Moreover, the building 21 is provided with first and second air inlets 22a and 22b on top of the first and second side walls 14a and 14b. The building 21 is provided with first and second partition walls 23a and 23b facing the inner surface sides of the first and second side walls 14a and 14b, respectively. The first and second partition walls 23a and 23b are fixed at the upper end to the ceiling wall 13, while the lower end is positioned with a predetermined gap from the installation floor 12, thereby the first and second intake ducts 24a. , 24b are provided. The first and second air intake ducts 24 a and 24 b communicate the first and second air intake ports 22 a and 22 b with the installation floor 12 side in the building 21.

  The building 21 is provided in a central portion of the ceiling wall 13, that is, an intermediate position between the first side wall 14 a and the second side wall 14 b of the ceiling wall 13 so that the ventilation tower 25 protrudes upward. The ventilation tower 25 communicates with the interior of the building 21 and is provided with first and second exhaust ports 26a and 26b on the side walls on the first and second side walls 14a and 14b side.

  The building 21 has a first radioactive substance arrangement region A1 adjacent to the first side wall 14a with a middle portion between the first side wall 14a and the second side wall 14b, and a second adjacent to the second side wall 14b. Radioactive substance arrangement | positioning area | region A2 is provided. A non-radioactive substance arrangement area B is provided between the first radioactive substance arrangement area A1 and the second radioactive substance arrangement area A2. In this case, the cask 10 is placed in the first and second radioactive substance arrangement areas A1 and A2, but the cask 10 is not placed in the non-radioactive substance arrangement area B.

  And in the building 21, the shielding board 27 is arrange | positioned in the area | region which connects the some cask 10 arrange | positioned on the installation floor 12, and the 1st, 2nd exhaust port 26a, 26b. Specifically, the shielding plate 27 is arranged in a region connecting the first and second radioactive substance arrangement regions A1 and A2 and the first and second exhaust ports 26a and 26b. The shielding plate 27 is formed of a concrete wall so that the radiation from each cask 10 is blocked, and is supported by a plurality of beams 28 installed on the third and fourth side walls 14c and 14d.

  That is, the plurality of caskes 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, and radiation is emitted upward. In this case, the radiation area Sa surrounded by the area lines La1 and La2 that linearly go from the respective cask 10 in the first radioactive substance arrangement area A1 to the second exhaust port 26b, and the respective cask 10 in the second radioactive substance arrangement area A2. The radiation region Sb surrounded by the region lines Lb1 and Lb2 linearly extending from the first exhaust port 26a to the first exhaust port 26a is formed, and the shielding plate 27 is disposed horizontally in the two radiation regions Sa and Sb. Yes.

  Accordingly, the plurality of casks 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, so that radiation is emitted upward from each of the casks 10, but straight to the exhaust ports 26a and 26b. Directly directed radiation is shielded by the ceiling wall 13, the side wall 14, the ventilation tower 25, and the like. And the radiation which goes straight from each cask 10 to each exhaust port 26a, 26b is shielded by the shielding plate 27 arranged in each radiation area Sa, Sb.

  In addition, as shown in FIG. 3, the outside air is taken in from the first and second intake ports 22a and 22b, descends through the first and second ducts 24a and 24b, and is disposed on the installation floor 12. The cask 10 is cooled. Then, each cask 10 is cooled and the air rises so as to bypass the shielding plate 27 and is discharged to the outside from the first and second exhaust ports 26a and 26b. In this case, the air heated by cooling the cask 10 rises and is discharged to the outside through the first and second exhaust ports 26a and 26b, so that the inside of the building 21 becomes negative pressure and the outside air is the first, The air is sucked from the second intake ports 22a and 22b and taken into the first and second ducts 24a and 24b.

  As described above, in the radioactive substance storage facility according to the first embodiment, the building 21 having a hollow shape and capable of arranging a plurality of casks 10 on the installation floor 12 inside, and the upper portion of the side wall 14 in the building 21 are provided. Region Sa connecting the plurality of cask 10 and the exhaust ports 26a, 26b arranged on the installation floor 12, the exhaust ports 26a, 26b provided in the central portion of the ceiling wall 13 in the building 21; A shielding plate 27 provided on Sb is provided.

  Therefore, the shielding plate 27 is provided in the areas Sa and Sb connecting the cask 10 and the exhaust ports 26a and 26b arranged on the installation floor 12, so that the radiation emitted from the cask 10 is shielded by the shielding plate 27. Radiation that leaks linearly from the cask 10 to the outside through the exhaust ports 26a and 26b can be appropriately prevented. In addition, air inlets 22 a and 22 b are provided at the upper part of the side wall 14, while air outlets 26 a and 26 b are provided at the center of the ceiling wall 13, so that outside air that has entered through the air inlets 22 a and 22 b can be 10 is cooled and then discharged from the exhaust ports 26a and 26b, and the plurality of casks 10 are arranged in the outside air passage, whereby each of the casks 10 can be efficiently cooled.

  In the radioactive substance storage facility according to the first embodiment, the first and second intake ports 22a and 22b are provided on the upper portions of the first and second side walls 14a and 14b constituting the building 21, respectively. First and second intake ducts 24a and 24b are provided to communicate the intake ports 22a and 22b with the installation floor 12. Accordingly, the outside air that has entered through the first and second intake ports 22a and 22b flows to the installation floor 12 side of the building through the first and second intake ducts 24a and 24b, and passes through the plurality of casks 10 disposed therein. After cooling reliably, it will be discharged | emitted from exhaust port 26a, 26b, and the cooling efficiency of each cask 10 can be improved.

  Moreover, in the radioactive substance storage facility of Example 1, the building 21 opens first and second radioactive substance arrangement areas A1 and A2 on the installation floor 12 adjacent to the first and second side walls 14a and 14b with an intermediate portion therebetween. Is provided. Therefore, it is possible to efficiently arrange each cask 10 in each radioactive substance arrangement region A1, A2 to improve cooling efficiency.

  FIG. 5 is a longitudinal sectional view showing the internal structure of the radioactive substance storage facility according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  In the second embodiment, as shown in FIG. 5, the building 21 of the storage facility 11 has upper ends of first and second side walls 14 a and 14 b and third and fourth side walls (not shown) provided on four sides of the installation floor 12. A ceiling wall 13 is provided at the part, and a plurality of caskes 10 can be arranged on the upper surface of the installation floor 12. The building 21 is provided with first and second intake ports 22a and 22b at the top of the first and second side walls 14a and 14b, and the first and second intake ports 22a and 22b communicate with the first and second intake ports 22a and 22b. Second intake ducts 24a and 24b are provided. Further, the building 21 is provided with a ventilation tower 25 at an intermediate position between the first side wall 14a and the second side wall 14b in the ceiling wall 13, and the ventilation tower 25 is provided with first and second exhaust ports 26a and 26b. Yes.

  Moreover, the building 21 is provided with a first radioactive substance arrangement area A1 and a second radioactive substance arrangement area A2 on the installation floor 13, and a non-radioactive substance arrangement area B is provided therebetween. In the building 21, a plurality of shielding plates 31a, 31b, 33a, 33b are arranged in a region connecting the plurality of casks 10 arranged on the installation floor 12 and the first and second exhaust ports 26a, 26b. Has been. Specifically, a plurality of shielding plates 31a, 31b, 33a, 33b are arranged in regions connecting the first and second radioactive substance arrangement regions A1, A2 and the first and second exhaust ports 26a, 26b. The shielding plates 31a, 31b, 33a, 33b are made of concrete walls so that the radiation from each cask 10 is blocked, and a plurality of beams 32a, 32b, 34a, 34b installed on the third and fourth side walls. It is supported by.

  That is, the plurality of caskes 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, and radiation is emitted upward. In this case, the radiation area Sa surrounded by the area lines La1 and La2 that linearly go from the respective cask 10 in the first radioactive substance arrangement area A1 to the second exhaust port 26b, and the respective cask 10 in the second radioactive substance arrangement area A2. A radiation region Sb surrounded by region lines Lb1 and Lb2 linearly extending from the first exhaust port 26a to the first exhaust port 26a is formed. The first upper shielding plate 31a and the first lower shielding plate 33a are formed corresponding to the radiation region Sa. Are arranged horizontally, and the second upper shielding plate 31b and the second lower shielding plate 33b are arranged horizontally corresponding to the radiation region Sb.

  In this case, the first upper shielding plate 31a and the first lower shielding plate 33a intersect the region line La3 linearly extending from each cask 10 of the first radioactive substance arrangement region A1 to the second exhaust port 26b, so that there is a gap. And the radiation region Sa can be shielded. Further, the second upper shielding plate 31b and the second lower shielding plate 33b intersect the region line Lb3 linearly extending from each cask 10 of the second radioactive substance arrangement region A2 to the first exhaust port 26a, so that there is no gap. The radiation region Sb can be shielded. Further, a cooling air passage 35 is provided so as to connect the non-radioactive substance arrangement region B and the first and second exhaust ports 26a and 26b.

  Accordingly, the plurality of casks 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, so that radiation is emitted upward from each of the casks 10, but straight to the exhaust ports 26a and 26b. Directly directed radiation is shielded by the ceiling wall 13, the side wall 14, the ventilation tower 25, and the like. And the radiation which goes straight from each cask 10 to each exhaust port 26a, 26b is shielded by the shielding plates 31a, 31b, 33a, 33b arranged in each radiation region Sa, Sb.

  The outside air is taken in from the first and second intake ports 22a and 22b, descends through the first and second intake ducts 24a and 24b, and cools the plurality of casks 10 disposed on the installation floor 12. . Then, each cask 10 is cooled and the air rises so as to bypass the shielding plates 31a, 31b, 33a, 33b, rises through the cooling air passage 35, and the first and second exhaust ports 26a, 26b. Is discharged to the outside.

  As described above, in the radioactive substance storage facility according to the second embodiment, the plurality of shielding plates 31a, 31b, and the regions Sa and Sb connecting the plurality of casks 10 and the exhaust ports 26a and 26b arranged on the installation floor 12 are provided. 33a and 33b are provided.

  Accordingly, the plurality of shielding plates 31a, 31b, 33a, and 33b are provided in the areas Sa and Sb that connect the cask 10 disposed on the installation floor 12 and the exhaust ports 26a and 26b, so that the radiation emitted from the cask 10 is shielded. By being shielded by 31a, 31b, 33a, and 33b, radiation that leaks linearly from the cask 10 to the outside through the exhaust ports 26a and 26b can be appropriately prevented.

  Further, in the radioactive substance storage facility of Example 2, the first shielding plates 31a and 33a provided in the area Sa connecting the cask 10 arranged in the first radioactive substance arrangement area A1 and the second exhaust port 26b, and the first 2nd shielding board 31b, 33b provided in area | region Sb which connects the cask 10 arrange | positioned in 2 radioactive substance arrangement | positioning area | region A2 and the 1st exhaust port 26a is provided. Therefore, by dividing into the first shielding plates 31a and 33a and the second shielding plates 31b and 33b, the space between the first and second shielding plates 31a, 31b, 33a and 33b is used as a space portion, so that the internal air can be efficiently used. To the first and second exhaust ports 26a, 26b.

  In the radioactive substance storage facility of Example 2, the first upper shielding plate 31a, the first lower shielding plate 33a, the second upper shielding plate 31b, and the second lower shielding plate 33b are provided. Therefore, by arranging the plurality of shielding plates 31a, 31b, 33a, and 33b to be shifted vertically and horizontally, the shielding area along the horizontal direction that shields the radiation regions Sa and Sb is reduced, and the manufacturing cost is reduced. Can do.

  In the radioactive substance storage facility of the second embodiment, the cooling air passage 35 is provided so as to connect the non-radioactive substance arrangement region B and the first and second exhaust ports 26a and 26b. Therefore, the air in the vicinity of the cask 10 can be efficiently guided to the first and second exhaust ports 26a and 26b.

  6 is a longitudinal sectional view showing the internal structure of the radioactive substance storage facility according to the third embodiment of the present invention, and FIG. 7 is a longitudinal sectional view showing the flow of cooling air in the radioactive substance storage facility according to the third embodiment. is there. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  In Example 3, as shown in FIGS. 6 and 7, the building 42 of the storage facility 41 includes an installation floor 43, a ceiling wall 44, and first and second side walls 45 a and 45 b and third, A plurality of caskes 10 can be arranged on the installation floor 43. In the building 42, first and second intake ports 46a and 46b are provided above the first and second side walls 45a and 45b, and the first and second intake ports 46a and 46b are provided by the partition walls 47a and 47b. First and second intake ducts 48a and 48b are provided in communication with each other. Further, the building 42 is provided with a ventilation tower 49 at an intermediate position between the first side wall 45a and the second side wall 45b in the ceiling wall 44, and the ventilation tower 49 is provided with first and second exhaust ports 50a and 50b. Yes.

  Further, the building 42 has a step portion 51 (52a, 52b, 53a, 53b, 54a) on the upper surface of the installation floor 43 where the exhaust ports 50a, 50b are higher than the intake ports 46a, 46b and the cask 10 can be placed. , 54b, 55). The step 51 has the same position as the installation floor 43 in the first step, and is higher at almost the same height from the second step 52a, 52b to the fifth step 55. The fifth step 55 is a ventilation tower 49. It is located below.

  In this case, the steps 51, 52a, 53a, 54a, 55 are set as the first radioactive substance arrangement area A1, and the steps 51, 52b, 53b, 54b, 55 are set as the second radioactive substance arrangement area A2, The non-radioactive substance arrangement region B is set in FIG. In the building 42, a plurality of shielding plates 56a and 56b are arranged in a region connecting the plurality of casks 10 arranged on the step portion 51 and the first and second exhaust ports 50a and 50b. Specifically, two shielding plates 56a and 56b are arranged in a region connecting the first and second radioactive substance arrangement regions A1 and A2 and the first and second exhaust ports 50a and 50b. The shielding plates 56a and 56b are made of concrete walls so that the radiation from each cask 10 is blocked, and are supported by a plurality of beams 57a and 57b installed on the third and fourth side walls.

  That is, the plurality of caskes 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, and radiation is emitted upward. In this case, the radiation area Sa surrounded by the area lines La1 and La2 that linearly go from the respective cask 10 in the first radioactive substance arrangement area A1 to the second exhaust port 50b, and the respective cask 10 in the second radioactive substance arrangement area A2. A radiation region Sb surrounded by region lines Lb1 and Lb2 linearly extending from the first exhaust port 50a to the first exhaust port 50a is formed, and the first upper shielding plate 56a is horizontally arranged corresponding to the radiation region Sa. The second upper shielding plate 56b is horizontally arranged corresponding to the radiation region Sb. Further, a cooling air passage 58 is provided so as to connect the non-radioactive substance arrangement region B and the first and second exhaust ports 50a and 50b.

  Accordingly, the plurality of casks 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, so that radiation is emitted upward from each of the casks 10, but straight to each of the exhaust ports 50a and 50b. Directly directed radiation is shielded by the ceiling wall 44, the side wall 45, the ventilation tower 49, and the like. And the radiation which goes straight from each cask 10 to each exhaust port 50a, 50b is shielded by shielding plates 56a, 56b arranged in each radiation region Sa, Sb.

  The outside air is taken in from the first and second intake ports 46a and 46b, descends through the first and second ducts 48a and 48b, and cools the plurality of casks 10 arranged in the step portion 51. Then, each cask 10 is cooled and the air rises so as to bypass the shielding plates 56a and 56b, rises through the cooling air passage 58, and is discharged to the outside from the first and second exhaust ports 50a and 50b. Is done.

  As described above, in the radioactive substance storage facility according to the third embodiment, a plurality of shielding plates are provided in the areas Sa and Sb connecting the plurality of casks 10 disposed on the stepped portion 51 of the installation floor 43 and the exhaust ports 50a and 50b. 56a and 56b are provided.

  Accordingly, the plurality of shielding plates 56a and 56b are provided in the regions Sa and Sb connecting the cask 10 disposed in the step portion 51 and the exhaust ports 50a and 50b, so that the radiation emitted from the cask 10 is transmitted by the shielding plates 56a and 56b. By shielding, radiation that leaks linearly from the cask 10 to the outside through the exhaust ports 50a and 50b can be prevented appropriately.

  Further, in the radioactive substance storage facility according to the third embodiment, the installation floor 43 of the building 42 is provided with a step portion 51 on which the exhaust ports 50a and 50b side is higher than the intake ports 46a and 46b and the cask 10 can be placed. Yes. Therefore, by disposing the cask 10 up and down, the radiation shielding area by the shielding plates 56a and 56b is reduced, and the manufacturing cost can be reduced.

  FIG. 8 is a longitudinal sectional view showing the internal structure of a radioactive substance storage facility according to Embodiment 4 of the present invention. In addition, the same code | symbol is attached | subjected to the member which has the function similar to the Example mentioned above, and detailed description is abbreviate | omitted.

  In the fourth embodiment, as shown in FIG. 8, the building 42 of the storage facility 41 includes an installation floor 43, a ceiling wall 44, first and second side walls 45a and 45b, and third and fourth side walls (not shown). The plurality of caskes 10 can be arranged on the installation floor 43. The building 42 is provided with first and second air inlets 46a and 46b at the upper portions of the first and second side walls 45a and 45b, and also communicates with the first and second air inlets 46a and 46b. Two intake ducts 48a and 48b are provided. Further, the building 42 is provided with a ventilation tower 49 at an intermediate position between the first side wall 45a and the second side wall 45b in the ceiling wall 44, and the ventilation tower 49 is provided with first and second exhaust ports 50a and 50b. .

  Further, the building 42 has a step portion 51 (52a, 52b, 53a, 53b, 54a) on the upper surface of the installation floor 43 where the exhaust ports 50a, 50b are higher than the intake ports 46a, 46b and the cask 10 can be placed. , 54b, 55). The step 51 has the same position as the installation floor 43 in the first step, and is higher at almost the same height from the second step 52a, 52b to the fifth step 55. The fifth step 55 is a ventilation tower 49. It is located below.

  In addition, the first radioactive substance arrangement area A1 is set in the step parts 51, 52a, 53a, 54a, 55, and the second radioactive substance arrangement area A2 is set in the step parts 51, 52b, 53b, 54b, 55. A non-radioactive substance arrangement region B is set. In the building 42, a plurality of shielding plates 61a, 61b, 63a, 63b are arranged in a region connecting the plurality of casks 10 arranged on the step portion 51 and the first and second exhaust ports 50a, 50b. Has been. Specifically, a plurality of shielding plates 61a, 61b, 63a, 63b are arranged in regions connecting the first and second radioactive substance arrangement regions A1, A2 and the first and second exhaust ports 50a, 50b. The shielding plates 61a, 61b, 63a, 63b are made of concrete walls so that the radiation from each cask 10 is blocked, and a plurality of beams 62a, 62b, 64a, 64b installed on the third and fourth side walls. It is supported by.

  That is, the plurality of caskes 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, and radiation is emitted upward. In this case, the radiation area Sa surrounded by the area lines La1 and La2 that linearly go from the respective cask 10 in the first radioactive substance arrangement area A1 to the second exhaust port 50b, and the respective cask 10 in the second radioactive substance arrangement area A2. A radiation region Sb surrounded by region lines Lb1 and Lb2 linearly extending from the first exhaust port 50a to the first exhaust port 50a is formed, and the first upper shielding plate 61a and the first lower shielding plate 63a are formed corresponding to the radiation region Sa. Are arranged horizontally, and the second upper shielding plate 61b and the second lower shielding plate 63b are arranged horizontally corresponding to the radiation region Sb.

  In this case, the first upper shielding plate 61a and the first lower shielding plate 63a cross the region line La3 that linearly extends from each cask 10 of the first radioactive substance arrangement region A1 to the second exhaust port 50b, so that there is a gap. And the radiation region Sa can be shielded. Further, the second upper shielding plate 61b and the second lower shielding plate 63b intersect the region line Lb3 linearly extending from each cask 10 of the second radioactive substance arrangement region A2 to the first exhaust port 50a, so that there is no gap. The radiation region Sb can be shielded. Further, a cooling air passage 65 is provided so as to connect the non-radioactive substance arrangement region B and the first and second exhaust ports 50a and 50b.

  Accordingly, the plurality of casks 10 are arranged in the first and second radioactive substance arrangement regions A1 and A2, so that radiation is emitted upward from each of the casks 10, but straight to each of the exhaust ports 50a and 50b. Directly directed radiation is shielded by the ceiling wall 44, the side wall 45, the ventilation tower 49, and the like. And the radiation which goes straight from each cask 10 to each exhaust port 50a, 50b is shielded by the shielding plates 61a, 61b, 63a, 63b arranged in each radiation region Sa, Sb.

  The outside air is taken in from the first and second intake ports 46a and 46b, descends through the first and second ducts 48a and 48b, and cools the plurality of casks 10 arranged in the step portion 51. Then, each cask 10 is cooled, and the air rises so as to bypass the shielding plates 61a, 61b, 63a, 63b, rises through the cooling air passage 65, and the first and second exhaust ports 50a, 50b. Is discharged to the outside.

  As described above, in the radioactive substance storage facility according to the fourth embodiment, a plurality of shielding plates are provided in the areas Sa and Sb connecting the plurality of casks 10 disposed on the stepped portion 51 of the installation floor 43 and the exhaust ports 50a and 50b. 61a, 61b, 63a, 63b are provided.

  Accordingly, the plurality of shielding plates 61a, 61b, 63a, 63b are provided in the regions Sa, Sb connecting the cask 10 disposed in the step portion 51 and the exhaust ports 50a, 50b, so that the radiation emitted from the cask 10 is shielded. By being shielded by 61a, 61b, 63a, 63b, radiation that leaks linearly from the cask 10 to the outside through the exhaust ports 50a, 50b can be prevented appropriately.

  Further, in the radioactive substance storage facility of Example 4, the first upper shielding plate 61a, the first lower shielding plate 63a, the second upper shielding plate 61b, and the second lower shielding plate 63b are provided. Therefore, by arranging the plurality of shielding plates 61a, 61b, 63a, 63b to be shifted vertically and horizontally, the shielding area along the horizontal direction that shields the radiation regions Sa, Sb is reduced, and the manufacturing cost is reduced. Can do.

  In each of the above-described embodiments, the number of shielding plates is one, two, or four. However, the number is not limited to this number, and may be appropriately set according to the size and shape of a building or the like. Is. In this case, the shielding plate may be arranged not only horizontally but also inclined.

  Moreover, in each Example mentioned above, although the 1st radioactive substance arrangement | positioning area | region and the 2nd radioactive substance arrangement | positioning area | region were provided in the building and the non-radioactive substance arrangement | positioning area was provided between them, the whole building is also used as a radioactive substance arrangement | positioning area | region. Often. In this case, in Examples 2 to 4, since the cask is also arranged in the non-radioactive substance arrangement region, the existing shielding plate is extended to the cooling air passage, or the cooling air passage is connected to the surrounding shielding plates. Alternatively, another shielding plate may be arranged by shifting up and down.

11, 41 Storage facility 12, 43 Installation floor 13, 44 Ceiling wall 14, 14a, 14b, 14c, 14d, 45a, 45b Side wall 21, 42 Building 22a, 22b, 46a, 46b Inlet 24a, 24b, 48a, 48b Intake Duct 26a, 26b, 50a, 50b Exhaust port 27 Shield plate 31a, 61a First upper shield plate 31b, 61b Second upper shield plate 33a, 63a First lower shield plate 33b, 63b Second lower shield plate 56a First shield plate 56b 2nd shielding board

Claims (7)

A building having a hollow shape and capable of disposing a radioactive substance on the inner floor surface and having at least a side wall and a ceiling having a radiation shielding function;
An air inlet provided in the upper side wall of the building;
An exhaust port provided in the center of the ceiling in the building;
A shielding plate provided in a region connecting the radioactive substance disposed on the floor and the exhaust port;
A radioactive substance storage facility comprising:   The side wall includes first and second side walls that face each other, and first and second air inlets are provided on top of the first and second side walls, respectively, and the first and second air inlets and 2. The radioactive substance storage facility according to claim 1, wherein first and second air intake ducts communicating with a floor side of the building are provided. 3.   3. The radioactive substance storage according to claim 2, wherein the building is provided with first and second radioactive substance arrangement regions on the floor surface adjacent to the first and second side walls with an intermediate portion therebetween. Facilities.   The shielding plate includes a first shielding plate provided in a region connecting the radioactive material arranged in the first radioactive material arrangement region and the exhaust port, and the radioactive material arranged in the second radioactive material arrangement region. The radioactive substance storage facility according to claim 3, further comprising a second shielding plate provided in a region connecting the exhaust port and the exhaust port.   5. The radioactive substance storage facility according to claim 4, wherein each of the first and second shielding plates includes an upper shielding plate and a lower shielding plate that are divided into upper and lower portions.   A non-radioactive substance arrangement area where the radioactive substance is not arranged is provided between the first and second radioactive substance arrangement areas, and a cooling air passage is provided so as to connect the non-radioactive substance arrangement area and the exhaust port. The radioactive substance storage facility according to claim 4 or 5.   7. The step according to claim 1, wherein the floor of the building is provided with a step portion on which the exhaust port side is higher than the intake port side and on which the radioactive substance can be arranged. Radioactive material storage facility.

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