Spent nuclear fuel storage container structured to reduce internal pressure

Abstract

The present invention relates to a spent nuclear fuel storage container structured to reduce internal pressure, the storage container having at least one recess formed on the outer surface of a canister in which at least one spent nuclear fuel assembly is accommodated, and a support coupled to the inner surface of a cask, in which the canister is accommodated, and inserted in the recess, thereby reducing the internal pressure of the storage container.

Description

Spent nuclear fuel storage vessel with internal pressure reduction structure

[0001] The present invention relates to a spent nuclear fuel storage container having an internal pressure reduction structure, and more specifically, to a storage container capable of reducing internal pressure generated while storing spent nuclear fuel for a long period of time.

[0002] Spent nuclear fuel, which is nuclear fuel used in nuclear power plants, contains radioactive materials and must be safely disposed of in a separate storage container.

[0003] Typically, spent nuclear fuel assemblies are stored on the nuclear power plant site for a certain period of time, then loaded into specially designed storage containers and transported to an interim storage facility.

[0004] However, when spent nuclear fuel assemblies are stored in a storage container for a long period of time, radioactive gases are generated due to radioactive decay of the spent nuclear fuel assemblies, and as these gases accumulate inside the container, the pressure inside the storage container increases.

[0005] This poses a risk of cracking or damage to the container walls, potentially shortening the container's design life.

[0006] Additionally, there is a problem that the radioactive gas accumulated inside the storage container may leak to the outside.

[0007] [Prior Art Literature]

[0008] [Patent Document]

[0009] Korean Patent Publication No. 10-2615120 (registration date: June 15, 2023)

[0010] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a spent nuclear fuel storage container having an internal pressure reducing structure capable of reducing the internal pressure of the storage container by forming at least one concave portion on the outer surface of a canister containing at least one spent nuclear fuel assembly therein, and inserting a support body into the concave portion by bonding the support body to the inner surface of a cask containing the canister.

[0011] A spent nuclear fuel storage container having an internal pressure reduction structure according to the present invention may include a canister having at least one spent nuclear fuel assembly accommodated therein and including at least one concave portion formed concavely in the direction of the spent nuclear fuel assembly on an outer surface, a cask having the canister accommodated therein, and a support coupled to an inner surface of the cask and inserted into the concave portion.

[0012] Additionally, the concave portion may be formed at the lower end based on the longitudinal direction of the canister.

[0013] Additionally, the support may have a shape corresponding to the shape of the concave portion.

[0014] Additionally, the canister may have a plurality of concave portions formed in the direction of the spent nuclear fuel assembly, and the support may have a plurality of convex portions formed in the direction of the spent nuclear fuel assembly.

[0015] Additionally, the concave portion may have one of a cylindrical shape, a prism shape, and a hemispherical shape.

[0016] Additionally, the support may include a first support in contact with the concave portion and a second support coupled to the inner surface of the cask.

[0017] Additionally, the first support and the second support may be made of a thermally conductive material.

[0018] Additionally, the thermal conductivity of the first support may be greater than the thermal conductivity of the second support.

[0019] Additionally, the strength of the first support may be less than the strength of the second support.

[0020] According to the present invention, there is an advantage in that the internal pressure of a storage container can be reduced when storing spent nuclear fuel for a long period of time.

[0021] FIG. 1 is a cross-sectional view showing a spent nuclear fuel storage container having an internal pressure reduction structure according to various embodiments of the present invention.

[0022] FIGS. 2A to 2C are perspective views showing the shapes of a concave portion and a support of a spent nuclear fuel storage container having an internal pressure reduction structure according to the first, second, and third embodiments of the present invention.

[0023] FIG. 3 is a perspective view showing the shape of a concave portion and a support of a spent nuclear fuel storage container having an internal pressure reduction structure according to a fourth embodiment of the present invention.

[0024] FIG. 4 is a cross-sectional view showing the shapes of the first support and the second support of a spent nuclear fuel storage container having an internal pressure reduction structure according to the fifth embodiment of the present invention.

[0025] Hereinafter, a spent nuclear fuel storage container having an internal pressure reduction structure according to the present invention, as described above, will be described in detail with reference to the attached drawings. The drawings presented below are provided as examples to ensure that those skilled in the art can sufficiently understand the spirit of the present invention. Therefore, the present invention is not limited to the drawings presented below and may be embodied in other forms. Furthermore, like reference numerals designate like elements throughout the specification.

[0026] In this case, if there is no other definition in the technical and scientific terms used, they have the meaning commonly understood by a person of ordinary skill in the technical field to which this invention belongs, and the description of known functions and configurations that may unnecessarily obscure the gist of the present invention in the following description and attached drawings are omitted.

[0027] FIG. 1 is a cross-sectional view showing a spent nuclear fuel storage container having an internal pressure reduction structure according to various embodiments of the present invention, FIGS. 2a to 2c are perspective views showing shapes of a concave portion and a support body of a spent nuclear fuel storage container having an internal pressure reduction structure according to first, second, and third embodiments of the present invention, FIG. 3 is a perspective view showing shapes of a concave portion and a support body of a spent nuclear fuel storage container having an internal pressure reduction structure according to a fourth embodiment of the present invention, and FIG. 4 is a cross-sectional view showing shapes of a first support body and a second support body of a spent nuclear fuel storage container having an internal pressure reduction structure according to a fifth embodiment of the present invention. With reference to FIGS. 1 to 4, a spent nuclear fuel storage container having an internal pressure reduction structure according to various embodiments of the present invention will be described in detail.

[0028] A spent nuclear fuel storage container having an internal pressure reduction structure according to various embodiments of the present invention may include a canister (100), a cask (200), and a support (300), as illustrated in FIG. 1.

[0029] Let's take a closer look at each component:

[0030] The canister (100) may have at least one spent nuclear fuel assembly (10) accommodated therein and may include at least one concave portion (110) formed concavely in the direction of the spent nuclear fuel assembly on the outer surface.

[0031] At this time, the canister (100) may have at least one receiving space formed therein in which at least one spent nuclear fuel assembly (10) can be received, and may be formed in a shape corresponding to the shape of the spent nuclear fuel assembly (10).

[0032] In addition, the canister (100) may be made of a material that protects the spent nuclear fuel assembly (10) from external impact and shields radiation emitted from the spent nuclear fuel assembly (10). Examples thereof include stainless steel, carbon steel, copper, titanium, etc. However, the material of the canister (100) is not limited thereto, and any material capable of protecting from external impact and shielding radiation may be used.

[0033] In addition, the concave portion (110) may be formed at the lower end based on the longitudinal direction of the canister (100). However, in order to reduce the internal pressure of the storage container, which is the purpose of the present invention, the concave portion (110) is formed at the lower end based on the longitudinal direction of the canister (100), and the position of the concave portion (110) is not limited thereto, and any position that can reduce the internal pressure of the storage container is possible.

[0034] Here, the concave portion (110) can be formed in various shapes along the direction of the spent nuclear fuel assembly (10), which will be described in detail later.

[0035] The above cask (200) can accommodate the canister (100) inside.

[0036] At this time, the cask (200), like the canister (100), may be made of a material capable of protecting against external impact and shielding radiation, such as stainless steel, carbon steel, copper, titanium, etc. However, the present invention is not limited thereto.

[0037] The above support (300) can be combined with the inner surface of the cask (200) and inserted into the concave portion (110).

[0038] In detail, one side of the support (300) is bonded to the inner surface of the cask (200), and the other side can come into contact with the concave portion (110).

[0039] Additionally, the support (300) may have a shape corresponding to the shape of the concave portion (110).

[0040] Here, as the concave portion (110) is formed into various shapes, the support (300) can also be formed into various shapes, which will be described in detail later.

[0041] The concave portion (110) and support (300) of the spent nuclear fuel storage container having an internal pressure reduction structure according to various embodiments of the present invention can be formed in various shapes.

[0042] [Example 1]

[0043] Referring to FIG. 2a, the concave portion (110) of the spent nuclear fuel storage container having an internal pressure reduction structure according to the first embodiment of the present invention can be formed in a cylindrical shape.

[0044] Additionally, the support (300) can be formed into a cylindrical shape corresponding to the shape of the concave portion (110).

[0045] In other words, the surface where the above concave portion (110) and the above support (300) face each other is circular.

[0046] [Example 2]

[0047] Referring to FIG. 2b, the concave portion (110) of the spent nuclear fuel storage container having an internal pressure reduction structure according to the second embodiment of the present invention can be formed in a prism shape.

[0048] In addition, the support (300) can be formed in a cylindrical shape corresponding to the shape of the concave portion (110).

[0049] In other words, the surface where the above concave portion (110) and the above support (300) face each other has an N-gonal shape (N = 3, 4, 5...).

[0050] [Example 3]

[0051] Referring to FIG. 2c, the concave portion (110) of the spent nuclear fuel storage container having an internal pressure reduction structure according to the third embodiment of the present invention can be formed in a semicircular shape.

[0052] Additionally, the support (300) may be formed in a semicircular shape corresponding to the shape of the concave portion (110).

[0053] In other words, the surface where the above concave portion (110) and the above support (300) face each other is in the shape of an arc.

[0054] If we compare the internal pressure reduction effects of the concave portion (110) and the support (300) of the spent nuclear fuel storage container having the internal pressure reduction structure according to the first to third embodiments of the present invention, which are cylindrical, semicircular, and prism shapes,

[0055] First, the cylindrical shape of the concave portion (110) and the support (300) of the spent nuclear fuel storage container having an internal pressure reduction structure according to the first embodiment of the present invention is an axially symmetrical structure that can evenly distribute the load for external and internal pressures, thereby having the greatest effect of reducing internal pressure.

[0056] Next, the semicircular shape of the concave portion (110) and the support (300) of the spent nuclear fuel storage container having an internal pressure reduction structure according to the third embodiment of the present invention is less stable than the cylindrical shape, but has a curved surface, so that a certain degree of load distribution is possible, and thus, it has an intermediate level of internal pressure reduction effect.

[0057] Lastly, the prism shape of the concave portion (110) and the support (300) of the spent nuclear fuel storage container having the internal pressure reduction structure according to the second embodiment of the present invention has corners and planes, so pressure can be concentrated, and in particular, stress concentration occurs at the corner portion, making deformation likely to occur, and the internal pressure reduction effect is the lowest compared to the cylindrical shape and the semicircular shape.

[0058] [Example 4]

[0059] Referring to FIG. 3, the canister (100) of the spent nuclear fuel storage container having an internal pressure reduction structure according to the fourth embodiment of the present invention may have a plurality of concave portions (110) formed in the direction of the spent nuclear fuel assembly (10), and the support (300) may have a plurality of convex portions (310) formed in the direction of the spent nuclear fuel assembly (10).

[0060] In detail, the canister (100) has a plurality of concave portions (110) alternately formed in the direction of the spent nuclear fuel assembly (10) with a predetermined length, and the support (300) has a plurality of convex portions (310) alternately formed in the direction of the canister (100) with a predetermined length so as to correspond to the shape of the plurality of concave portions (110) formed in the canister (100), and the plurality of convex portions (310) are inserted into the plurality of concave portions (110).

[0061] Accordingly, the spent nuclear fuel storage container having an internal pressure reduction structure according to the fourth embodiment of the present invention also has the effect of allowing the internal pressure to be distributed over a wide area rather than being concentrated at a specific point.

[0062] In the present invention, the shapes of the concave portion (110) and the support (300) are described by dividing them into the first to fourth embodiments, but are not limited thereto, and any shape that can reduce the internal pressure of the storage container is possible.

[0063] The spent nuclear fuel storage container having an internal pressure reduction structure according to various embodiments of the present invention has the main purpose of reducing the internal pressure, but due to the characteristics of spent nuclear fuel, it is also necessary to minimize damage from radiation or heat emission.

[0064] Accordingly, the support (300) of the spent nuclear fuel storage container having an internal pressure reduction structure according to the fifth embodiment of the present invention may include a first support (320) in contact with the concave portion (110) and a first support (330) coupled to the inner surface of the cask (200), as illustrated in FIG. 4.

[0065] In detail, the support (300) may be arranged such that the first support (320) is positioned at the top and the first support (330) is positioned at the bottom, based on the longitudinal direction of the spent nuclear fuel assembly (10).

[0066] Here, the first support (320) and the first support (330) may be made of a thermally conductive material to discharge heat emitted from the spent nuclear fuel assembly (10) to the outside.

[0067] Additionally, the thermal conductivity () of the first support (320) may be greater than the thermal conductivity of the first support (330).

[0068] Additionally, the strength of the first support (320) may be less than the strength of the first support (330).

[0069] For example, the first support (320) may be made of copper, silver, aluminum, etc., and the first support (330) may be made of stainless steel, titanium, aluminum alloy, etc. However, the materials of the first support (320) and the first support (330) are not limited thereto, and any material may be used as long as both the first support (320) and the first support (330) are thermally conductive materials, the thermal conductivity of the first support (320) is greater than the thermal conductivity of the first support (330), and the strength of the first support (320) is less than the strength of the first support (330).

[0070] Due to this, the heat emitted from the spent nuclear fuel assembly (10) can be well released to the outside, and there is an effect of protecting it from external impact.

[0071] In summary, a spent nuclear fuel storage container having an internal pressure reduction structure according to various embodiments of the present invention has the advantage of being able to reduce the internal pressure of the storage container by forming at least one concave portion on the outer surface of a canister in which at least one spent nuclear fuel assembly is accommodated, and inserting a support body into the concave portion by combining the support body with the inner surface of a cask in which the canister is accommodated.

[0072] Although preferred embodiments of the present invention have been described above, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but rather to explain it. Therefore, the technical spirit of the present invention includes not only each disclosed embodiment but also combinations of disclosed embodiments, and further, the scope of the technical spirit of the present invention is not limited by these embodiments. Furthermore, those skilled in the art to which the present invention pertains may make numerous changes and modifications to the present invention without departing from the spirit and scope of the appended claims, and all such appropriate changes and modifications should be considered as equivalents and falling within the scope of the present invention.

[0073] [Explanation of symbols]

[0074] 10: Spent nuclear fuel assembly

[0075] 100: Canister

[0076] 110: Concave

[0077] 200: Cask

[0078] 300: Support

[0079] 310: Convex part

[0080] 320: First support

[0081] 330: Second support

Claims

1. A canister having at least one spent nuclear fuel assembly accommodated therein and including at least one concave portion formed concavely in the direction of the spent nuclear fuel assembly on an outer surface; a cask containing the canister therein; and A spent nuclear fuel storage container having an internal pressure reduction structure, comprising a support member coupled to the inner surface of the cask and inserted into the concave portion.

2. In paragraph 1, The above concave portion is, A spent nuclear fuel storage container having an internal pressure reduction structure formed at the lower end based on the longitudinal direction of the canister.

3. In paragraph 1, The above support is, A spent nuclear fuel storage container having an internal pressure reduction structure having a shape corresponding to the shape of the above concave portion.

4. In paragraph 3, The above canister, A plurality of concave portions are formed in the direction of the above-mentioned spent nuclear fuel assembly, The above support is, A spent nuclear fuel storage container having an internal pressure reduction structure in which a plurality of convex portions are formed in the direction of the spent nuclear fuel assembly.

5. In paragraph 3, The above concave portion is, A spent nuclear fuel storage container having an internal pressure reduction structure in one of the following shapes: cylindrical, prism-shaped, or hemispherical.

6. In paragraph 1, The above support is, A spent nuclear fuel storage container having an internal pressure reduction structure, the container including a first support in contact with the concave portion and a second support coupled to the inner surface of the cask.

7. In paragraph 6, A spent nuclear fuel storage container having an internal pressure reduction structure, wherein the first support and the second support are made of a thermally conductive material.

8. In paragraph 7, A spent nuclear fuel storage container having an internal pressure reduction structure, wherein the thermal conductivity of the first support is greater than the thermal conductivity of the second support.

9. In paragraph 6, A spent nuclear fuel storage container having an internal pressure reduction structure, wherein the strength of the first support is lower than the strength of the second support.

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