JP5866695B2 - Radioactive waste storage structure and radioactive waste storage method - Google Patents

Description

  The present invention can enclose various radioactive wastes contaminated with highly radioactive substances and store them safely for a long period of time. For example, it can be easily and stably stacked in a predetermined field. The present invention relates to a radioactive waste storage structure and a method for storing radioactive waste.

  Due to the earthquake and tsunami disaster on the Tohoku Pacific side in early March this year, a lot of highly radioactive materials (Cs, Sr, I, etc.) were scattered and contaminated by the highly radioactive materials due to the collapse of facilities in the Fukushima nuclear power plant. A large amount of radioactive debris and rubble are generated and collected, and are awaiting disposal and decontamination. However, the amount of radioactive waste and rubble is enormous, and there is a problem with the processing speed.

There is a natural desire for a treatment method to make radioactive waste contaminated with such highly radioactive substances as soon as possible, but rather than that, from the most important viewpoint of ensuring personal safety. There is a need for a structure that can safely store the enormous amount of radioactive waste described above. In addition, the application of the container disclosed in Patent Documents 1 and 2 proposed before the recent earthquake will be examined below.
Patent Document 1 assumes that spent fuel is stored in an internal radioactive substance storage container by closing the bottom and top of a thick concrete container formed into a substantially cylindrical shape.
Patent document 2 is a radiation shielding container provided with a stainless steel cylinder and a stainless steel lid that are used while being stored in a standard drum container, and there is also a description of using concrete as a container shielding body.

Japanese Patent Laid-Open No. 2004-144600 JP 2010-8224 A

However, the containers described in Patent Documents 1 and 2 are both substantially cylindrical and are not supposed to store a huge amount of radioactive waste as described above. No consideration was given to the work of performing the above or the stability thereof.
If a container with the above structure is installed in a predetermined field or the like and is left unattended, it is assumed with an extremely high possibility that an accident will occur in which the container falls over and falls. there were.

  Therefore, the present invention can enclose various radioactive wastes contaminated with highly radioactive substances and store them safely for a long period of time, for example, easily and stably piled up in a predetermined field or the like. The aim is to propose a radioactive waste storage structure.

The present invention has been proposed in view of the above, a concrete square-shaped main body that opens upward, a concrete lid that covers the open top of the main body, and a double that is disposed on the inner surface of the main body. A radioactive waste storage structure comprising a diffusion prevention film made of a laminated resin film , wherein the main body has an accommodating portion that is open at the top surrounded by a bottom surface and four side surfaces, and adjacent two each corner side surfaces intersect, with the inclined surface is provided for the second side to form the corners, the insert fitting into the interior of the inclined surface is embedded, from the outer surface side notch-like to the lower end of the total of four inclined surfaces recess is provided, the cover body, Takashi shaped portion facing the accommodating portion on the lower surface is provided at each corner, with the inclined surface is provided for the second side to form the corners, the inclined surface Insert metal fitting buried from inside Is made by, to accommodate the high-level radioactive waste into the interior of the diffusion preventing film arranged in the housing portion of the main body, the lid arranged so as to face the Takashijo portion accommodating portion, of the respective body and the lid By fixing the coupling metal so that it extends over each insert metal fitting on the inclined surface and the upper end protrudes upward from the upper surface of the lid, the inner surface side of the upper end of the coupling metal is stacked in the upper stage . relates storage structure of radioactive waste, characterized in that the outer surface of each recess of the lower end of the total of four inclined surfaces of the body of the storage structure can be respectively engaged.

In the storage structure according to the present invention, the radioactive waste storage structure can be lifted and moved in a state in which a wire lifted by a crane (hereinafter referred to as a suspension wire) is connected to the connection fitting. I also propose.

Further, the present invention comprises a concrete square-shaped main body that opens upward, a concrete lid that covers the open upper portion of the main body, and a double laminated resin film disposed on the inner surface of the main body. A method for storing radioactive waste using a storage structure comprising a diffusion prevention film , wherein the upper part surrounded by the bottom surface and the four side surfaces has an open storage part, and each corner where two adjacent side surfaces intersect in part, the inclined surface is provided for the second side to form the corners, is embedded an insert fitting into the interior from the inclined surface, the notch-like recess from the outer surface side is provided on the lower end of the total of four inclined surfaces A first step of installing a prismatic main body having a structure, and disposing a diffusion prevention film while being double-layered in a housing portion of the main body; and a step of accommodating high radioactive waste inside the diffusion prevention film. Step 2 and bottom surface The receiving portion faces Takashi shaped portion is provided, at each corner, with the inclined surface is provided for the second side to form the corners, the cover structure the insert fitting into the interior from the inclined surface is buried The third step of arranging the ridges so as to face the inside of the main body, and the upper end of the upper part projecting upward from the upper surface of the lid so as to straddle the insert fittings on the inclined surfaces of the main body and the lid. A fourth step of attaching the connecting bracket to the first, a fifth step of installing the storage structure having the above-mentioned configuration at a predetermined position, and an upper end of the connecting bracket of the lower storage structure by repeating the first to fifth steps. Also proposed is a method for storing radioactive waste, characterized in that the upper storage structure is stacked so that the inner surface side of the main body engages with the outer surface side of each recess at the lower end of a total of four inclined surfaces of the main body. It is.

The radioactive waste storage structure of the present invention can be safely stored for a long period of time by enclosing wastes such as various types of radioactive waste contaminated with highly radioactive substances. It can be easily and stably stacked.
Specifically, since the radioactive waste stored in the storage part of the storage structure of the present invention is surrounded by a double diffusion prevention film and a concrete layer composed of a main body and a lid, It will not diffuse or penetrate outside the storage structure and will be stored very safely.
In addition, the storage structure of the present invention has a structure in which the connecting fitting that connects the main body and the lid is fixed to the insert fitting embedded in the notch formed on the outside of the square. Half of the metal fittings are sufficient compared to the case, and even in the work of stacking with a crane etc., the suspension wire is half as compared with the case of fixing two places on four sides, so it is excellent in workability . Moreover, since the upper end of the coupling metal fitting can be engaged with the recess at the bottom of the upper storage structure, it can be stably stacked and placed, even if an earthquake or the like occurs, Misalignment can be prevented.
Furthermore, the raised portion of the lid is arranged so as to face the accommodating portion, and plays a role of position regulation when placing the lid on the upper part of the main body. In addition, it is possible to suppress the deviation after the lid is installed.

  In addition, when the hoisting wire can be lifted and moved in a state where the connecting metal is connected to the connecting metal, specifically, the hook may be fixed to the connecting metal and indirectly connected to the hanging wire, or a hole may be formed in the connecting metal. It may be formed and the suspension wire may be directly connected.

  Furthermore, the method for storing radioactive waste according to the present invention is to store using the storage structure having the above-described structure, and the radioactive waste stored in the storage structure is composed of a double diffusion prevention film, a main body, Surrounded by a concrete layer composed of a lid, it can be stored very safely without diffusing or penetrating outside the storage structure during storage.

It is a front view of the 1st example of the storage structure of the present invention. It is a top view of the storage structure. It is a bottom view of the storage structure. It is a right view of the said storage structure. It is sectional drawing in the VV line in FIG. It is sectional drawing in the VI-VI line in FIG. It is an expanded sectional view which shows the corner | angular part of the said storage structure. It is a front view which shows only the main body which comprises the said storage structure. It is a top view which shows only the main body which comprises the said storage structure. It is a bottom view which shows only the main body which comprises the said storage structure. It is a right view which shows only the main body which comprises the said storage structure. It is a front view which shows only the cover body which comprises the said storage structure. It is a top view which shows only the cover body which comprises the said storage structure. It is a bottom view which shows only the cover body which comprises the said storage structure. It is a right view which shows only the cover body which comprises the said storage structure. It is a perspective view of the storage structure. It is a disassembled perspective view of the said storage structure. It is a perspective view which shows the suspended state which attaches a cover body with respect to a main body. It is a perspective view which shows the suspended state at the time of stacking the said storage structure in multistage.

  The radioactive waste storage structure of the present invention includes a concrete square-shaped main body that opens upward, a concrete lid that covers the open upper portion of the main body, and a double structure disposed on the inner surface of the main body. It is the structure which consists of a laminated | stacked diffusion prevention film.

  As the main body and lid constituting the storage structure in the present invention, any concrete such as fiber reinforced concrete mixed with steel fiber, glass fiber, etc., resin impregnated concrete in which the surface is impregnated with resin to increase the density, etc. Alternatively, reinforced concrete provided with reinforcing materials such as reinforcing bars may be used.

The main body is a molded body formed in a substantially square-shaped shape, and has a shape having an accommodating portion that is open at the top surrounded by the bottom surface and the four side surfaces, and the outside of each corner portion where two adjacent side surfaces intersect. A notch is provided in the insert, and an insert fitting is embedded from the notch into the inside. This notch is formed so as to be inclined by about 45 degrees with respect to the two side surfaces forming each corner, and an insert metal fitting is embedded inward from the notch. The size of the notch and the insert metal fitting are not particularly limited, and can be appropriately designed and selected. The provision of the “notch” in the present invention means that the molded body (the main body and the lid body) is formed in a shape that is notched, and the molded body is notched after some processing. Rather, it means adding notch molding to the concrete formwork.
Moreover, the recessed part is provided in four corners of the bottom face, respectively. This recessed portion corresponds to a locking receiving portion that locks the upper end of the connecting fitting described later, and can be appropriately designed and selected according to the size and shape of the upper end of the connecting fitting of the locking receiving portion.
The shape of the accommodating portion of the substantially square-shaped main body is not particularly limited. However, as shown in the illustrated embodiment described later, the corners ( It is desirable to form in a shape in which the corner portion inner surface protrudes inward.

The lid is a molded body formed in a substantially square disk shape, and a notch is provided on the outside of each corner, and an insert metal fitting is embedded from the notch to the inside. The notches and the insert fittings are the same as those provided at the corners of the main body, and thus the description thereof is omitted.
In addition, the lower surface of the lid is a surface facing the main body housing portion, but this lower surface is composed of a portion placed on the upper end of the main body and a portion not placed on the inside, and is not placed. The configuration in which the portion protrudes (raises) downward is referred to as a “provided with a raised portion facing the housing portion”. And, when the lid body is installed on the main body, the position restriction is achieved by making the planar shape of the raised portion substantially the same as the planar shape of the housing portion, and the installation work is easy. And it can carry out reliably, and after installing a cover body, a shift | offset | difference can be suppressed.

Since the connecting fittings are attached to the corners of the storage structure, four pieces are required. The connecting fitting is a fitting for connecting the main body and the lid, and the storage structure is stacked up and down. Also serves as a metal fitting (locking metal fitting) to prevent misalignment.
That is, this connecting bracket is attached so as to straddle each insert bracket embedded in the interior from each notch of the main body and the lid body, but the upper end protrudes above the lid body, so that the storage structure stacked in the upper stage is attached. It also serves as a locking metal fitting that locks into each recess at the bottom of the main body.
Therefore, as this connection metal fitting, a steel material formed into a U-shaped cross section as in the illustrated embodiment described later may be used, or a high strength steel bar, square steel, or the like may be used.

Further, a suspension wire may be directly or indirectly coupled to the coupling fitting, and the entire storage structure may be lifted and moved by a crane or the like.
When the suspension wire is directly connected to the connection fitting, a hole may be formed at the upper end to attach the suspension wire. When the connection wire is indirectly connected, the connection fitting is as shown in the illustrated embodiment described later. A hook or the like may be attached to the hook, and a hanging wire may be attached to the hook.

  Anti-diffusion film is used for the purpose of preventing the diffusion of radioactive substances as much as possible, and does not limit the material or thickness in particular. For example, it is versatile such as polypropylene, polyethylene, polyvinyl chloride, etc. A high resin film is thickly formed and further laminated in a double layer. For example, you may use what formed the thick sheet | seat used for a tent roof etc. in the bag shape. Also, if a film with extremely high shielding properties is found, it can be used as a matter of course.

For example, when protrusions are provided at the four corners of the upper end surface of the main body and recesses are provided at the four corners of the lower surface of the lid body, the lid body is installed to cover the open upper portion of the main body. In addition, like the above-described ridge portion of the lid body, this projection portion also serves to regulate the position, and the effect of the lid body can be easily set as in the case of the ridge portion. Deviation after installation can be suppressed.
In addition, a water-stopping material such as natural rubber or chloroprene rubber is provided between the main body and the lid so as to prevent infiltration of rainwater and the like, and leakage of contaminated water to the outside. good.

  The storage structure of this invention is comprised from each member of the said structure, About a detailed structure, it carries out with description of the illustrated Example mentioned later.

  The present invention will be described based on the embodiments of the drawings. In addition, this invention is not limited to an Example, It can implement in any way, unless the structure as described in a claim is changed.

The main body 2 and the lid 3 constituting the storage structure 1 of the present invention are made of concrete, but it is preferable to use ordinary concrete or heavy concrete having a density of 2.3 t / m ³ or more. Arranged reinforced concrete may be used. Since ordinary concrete is relatively inexpensive, it is suitable when a large amount of this storage structure is required. However, if there is a large amount of radioactivity diffusion from radioactive waste, the concrete density is high. It is desirable to use heavy concrete with high radiation shielding properties. This heavy concrete is a concrete with a density of 3.0 to 5.0 t / m ³ using heavy aggregates such as iron, barite, and iron ore with high specific gravity, so it shields the radioactivity caused by gamma rays, X-rays, etc. can do.
Table 1 shows the materials used for the concrete, Table 2 shows blending examples, Table 3 shows the fresh properties of the concrete, and Table 4 shows the physical properties of each concrete after curing and curing.

FIG. 1 is a front view of a first embodiment of a storage structure 1 according to the present invention, showing a state in which a concrete lid 3 is fitted to a concrete square-shaped main body 2.
The main body 2 has an accommodating portion 23 that is open on the upper side surrounded by the bottom surface 21 and the four side surfaces 22, and a notch 24 is provided outside each corner where the two adjacent side surfaces 22, 22 intersect, An insert metal fitting 25 is embedded from the notch 24 to the inside, and recesses 26 are provided at the four corners of the bottom surface.
The lid 3 has a configuration in which a ridge 31 that faces the accommodating portion 23 is provided on the lower surface, a notch 32 is provided outside each corner, and an insert fitting 33 is embedded from the notch 32 to the inside.
The connection metal fitting 4 is a steel material having a U-shaped cross section, and extends over the insert metal fitting 25 of the main body 2 and the insert metal fitting 33 of the lid body 3, and its upper end is from the upper surface of the lid body 3. It is fixed so as to protrude upward. Further, as shown in FIG. 7, a hook 41 is fixed to the connection fitting 4 so as to bend the rod-shaped material into a substantially U shape and to fix the arcuate tip to protrude outward.
In the state where the lid 3 is fitted to the main body 2, the ridge 31 of the lid 3 is arranged so as to face (fit) the accommodating portion 23 of the main body 2, and the notch 24 of the main body 2 The connecting metal fitting 4 is fixed across the insert metal fitting of the main body 2 and the insert metal fitting 33 of the lid body 3 so as to be in contact with the notch 32 of the cover body 3.
In addition, the double line shape drawn on the outline of each member has shown the chamfered part of a square top part.

FIG. 2 shows a plan view of the storage structure 1.
As is clear from the figure, the connection fitting 4 fixed to the notch 24 of the main body 2 extends over the lid 3.

FIG. 3 shows a bottom view of the storage structure 1, and FIG. 4 shows a right side view of the storage structure 1. FIG.
As is clear from the figure, recesses 26 are provided at the four corners of the bottom surface of the main body 2.

FIG. 5 is a sectional view taken along the line VV in FIG.
As is clear from the figure, the raised portion 31 formed on the lid 3 is disposed so as to face the accommodating portion 23 of the main body 2, and the position restriction when the lid 3 is placed on the upper portion of the main body 2. It plays a role and can be easily installed using a crane or the like.

  6 shows a cross-sectional view taken along line VI-VI in FIG.

FIG. 7 is an enlarged cross-sectional view showing a corner portion of the storage structure 1, in which the notch 24 of the main body 2 and the notch 32 of the lid body are brought into contact with each other, and the ridge portion 32 of the lid body 3 is fitted. Accordingly, the installation work of the lid body 3 with respect to the main body 2 can be easily performed, and the deviation after the installation of the lid body 3 can be suppressed.
And the connection metal fitting 4 can be easily attached so as to straddle the insert metal fitting 25 embedded inward from the notch 24 of the main body 2 and the insert metal fitting 33 embedded inward from the notch 32 of the lid 3. As described above, the hook 41 is fixed to the connection fitting 4 so that the arcuate tip protrudes outward.

  8 to 11 show a front view, a plan view, a bottom view, and a right side view of only the main body 2, and FIGS. 12 to 15 show a front view, a plan view, a bottom view, and a right side view of only the lid 3. The figure is shown.

  FIG. 16 shows the installed state of the storage structure 1. The radioactive waste (6) stored inside the dotted line is divided into the double diffusion prevention film 5, the main body 2 and the lid 3. Since it is surrounded by the constructed concrete layer, it does not diffuse or penetrate outside the storage structure 1 during storage, and is stored extremely safely.

FIG. 17 is an exploded perspective view of the storage structure 1, in which the main body 2 having the above-described configuration, the radioactive waste 6 accommodated therein, and the lid 3 having the above-described configuration are described.
The procedure for installing the storage structure 1 includes the following (1) to (5).
(1) First, the main body 1 is installed at a predetermined work place.
(2) Next, the double diffusion prevention film 5 is disposed on the inner surface of the storage portion 23 of the storage structure 1.
(3) The radioactive waste 6 is accommodated inside the diffusion preventing film 5 that is subsequently disposed.
(4) Thereafter, the surplus portion of the diffusion preventing film 5 is accommodated in the accommodating portion 23.
(5) Subsequently, the lid 3 is attached so as to cover the open upper portion of the main body 2.
(6) The connecting metal fittings 4 are attached and fixed to the corners of the main body 2 and the lid 3 respectively.
(7) Finally, in order to place the storage structure 1 in a predetermined storage position, the storage structure 1 is lifted and installed by a crane or the like.

The steps (1) and (2) can be easily performed because it is not necessary to consider the diffusion of radioactive materials. In connection with the installation of the main body 2, the connecting metal fitting 4 may be temporarily attached to the insert metal fitting 25 and lifted by a crane or the like to be installed at a desired location.
In the steps (3) to (6), it is necessary to consider the diffusion of the radioactive material from the radioactive waste 6, and therefore it is necessary to perform the work in a state where the worker is not as close as possible. Among these, at least the steps (3) and (5) can be carried out by lifting with a crane or the like, and can be carried out extremely safely.

FIG. 18 shows a state in which the lid 3 is lifted by a crane or the like (not shown) with respect to the main body 2 containing the radioactive waste 6 therein.
In the illustrated embodiment, the suspension wire 7 is attached to the insert fitting 33 and suspended. However, the connection fitting 4 having the above-described configuration is temporarily attached to connect the hook 41 of the connection fitting 4 to the suspension wire 7. It may be hung.
Thereafter, the lid 3 is attached to (insert metal fitting 25) so as to be disposed at a predetermined position of the main body 2 as in the above-described step (5), and in this state, as in the above-described step (6). In addition, the storage structure 1 is closed by fixing the connecting fitting 4 across the notch 24 of the main body 2 and the notch 32 (the insert fitting 33) of the lid 3.

FIG. 19 shows a state in which the storage structure 1 containing the radioactive waste 6 is lifted by a crane or the like (not shown).
As described above, the connecting metal fitting 4 is attached across the main body 2 (the insert metal fitting 25) and the lid 3 (the insert metal fitting 33), and is attached to each of the four corners. Since the hook 41 is fixed so that the arcuate tip protrudes outward, the suspension wire 7 is connected to the arcuate tip and suspended as shown.

  And these operations (work) can be repeated and the storage structure 1 can be piled up in multiple stages. At that time, since the upper end of the connection fitting 4 can engage with the recess 26 at the bottom of the upper storage structure 1, it can be stably stacked and placed even if an earthquake or the like occurs. Misalignment of the storage structure 1 can be prevented.

DESCRIPTION OF SYMBOLS 1 Storage structure 2 Main body 21 Bottom surface 22 Side surface 23 Accommodating part 24 Notch 25 Insert metal fitting 26 Recess 3 Lid body 31 Raised part 32 Notch 33 Insert metal fitting 4 Connecting metal fitting 41 Hook 5 Diffusion prevention film 6 Radioactive waste 7 Suspension wire

Claims (3)

It consists of a concrete square-shaped main body that opens upward, a concrete lid that covers the open top of the main body, and a diffusion prevention film that is a double-layered resin film disposed on the inner surface of the main body. A radioactive waste storage structure,
The main body has a housing portion that is open at the top and surrounded by a bottom surface and four side surfaces, and is provided with inclined surfaces with respect to two side surfaces forming each corner portion at each corner portion where two adjacent side surfaces intersect. , is embedded an insert fitting into the interior from the inclined surface, will be cut-shaped recess is provided from the outer surface side at the lower end of the total of four inclined surfaces,
The lid is provided with a ridge-like part facing the housing portion on the lower surface, at each corner, with the inclined surface is provided, the insert fitting into the interior from the inclined surface embedded for second side forming the corners Being
The highly radioactive waste is accommodated inside the diffusion preventing film disposed in the accommodating portion of the main body, the lid is disposed so that the ridges face the inside of the main body, and each of the inclined surfaces of the main body and the lid is arranged. The main body of the storage structure having the above-described structure in which the inner surface of the upper end of the connecting metal fitting is stacked in an upper stage by attaching the connecting metal fitting so that the upper end protrudes above the upper surface of the lid body so as to straddle the insert metal fitting. A radioactive waste storage structure characterized in that it can be respectively engaged with the outer surface side of each recess at the lower end of the four inclined surfaces . The radioactive waste storage structure according to claim 1, wherein the radioactive waste storage structure can be lifted and moved in a state where a wire lifted by a crane is connected to the connecting metal fitting. A storage structure comprising a square hook-shaped main body that opens upward, a lid that covers the open upper portion of the main body, and a diffusion prevention film that is a double-layered resin film disposed on the inner surface of the main body is used. A method for storing radioactive waste,
Has a housing part upwards to release surrounded by the bottom surface and four side surfaces, at each corner adjacent two sides intersect, the inclined surface is provided for the second side to form the corners, the inclined surface Insert brackets are embedded from the inside to the bottom, and a square rod-shaped main body with a configuration in which notched concave portions are provided from the outer surface side at the lower ends of a total of four inclined surfaces, and are laminated in the housing portion of the main body. A first step of disposing a diffusion preventing film;
A second step of containing highly radioactive waste inside the diffusion preventing film;
Provided Takashi shaped portion facing the accommodating portion on the lower surface, at each corner, with the inclined surface is provided for the second side to form the corners, the configuration of the lid insert fitting into the interior from the inclined surface is buried A third step of arranging the body such that the ridges face the inside of the main body;
A fourth step of attaching the connecting bracket so as to straddle the respective insert brackets on the inclined surfaces of the main body and the lid, and so that the upper end protrudes upward from the upper surface of the lid;
A fifth step of installing the storage structure having the above configuration at a predetermined position;
By repeating the first to fifth steps, the inner surface of the upper end of the coupling fitting of the lower storage structure is engaged with the outer surface of each recess at the lower end of the total four inclined surfaces of the main body, respectively . A method for storing radioactive waste, comprising stacking storage structures.

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