JPH10290968A - Water barrier material for burying waste - Google Patents

Abstract

(57) [Summary] [Problem] To provide a water impermeable buffer material for burying waste material, which can improve tensile strength, prevent breakage during transportation, and contribute to improvement of workability. SOLUTION: A water-blocking buffer material 10 is composed of a hollow-bottomed cylindrical main body 11 opening upward and a disk-shaped lid 12 closing the opening, and each of the bentonite has gravel and silica sand as aggregate. The mixture is formed by compressing and molding a mixture of glass fibers as a fibrous reinforcing material and glass fibers mixed into the whole.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an interposition between an inner surface of a burial hole and an outer surface of a container when a container containing waste is inserted and buried in a burial hole formed in a rock. The present invention relates to an impermeable buffer material for burying waste.

[0002]

2. Description of the Related Art As one method of disposing of hazardous waste,
Recently, it has been considered to be housed in a container and buried deep underground. That is, waste is stored in a container made of a corrosion-resistant and pressure-resistant metal, and this container is inserted into a burial hole formed in a rock to be buried.

However, when the container is buried in the ground as described above, the container is exposed to groundwater containing salt or the like for a long period of time. Such a situation is not preferable even for a corrosion-resistant and pressure-resistant container. Absent. In addition, the container may be damaged by displacement of the crust.

For this reason, a water-impervious cushioning material mainly composed of bentonite is interposed between the inner surface of the burial hole and the outer surface of the container,
It is conceivable that this water-blocking material blocks groundwater from the container and absorbs displacement of the crust to prevent damage to the container.

[0005] The impermeable buffer material is formed into a predetermined shape by mixing bentonite with an aggregate such as gravel and compression molding.

[0006]

However, as described above, a water-impeding cushioning material obtained by compression-molding a mixture of aggregate and bentonite can be integrally formed into a desired shape, thereby improving workability. However, there is a problem that transport is difficult due to low tensile strength and easy breakage. In particular, when the content of bentonite is reduced to increase economic efficiency, the strength is significantly deteriorated, and therefore, it must be used to stack those formed into small blocks and thus cannot enjoy the advantages of integral molding. Met.

[0007] The present invention has been made in view of the above problems, and can improve the tensile strength.
It is an object of the present invention to provide a water-impeding buffer material for burying waste, which can prevent damage during transportation and contribute to improvement of workability.

[0008]

A water impermeable buffer material for burying waste according to the present invention, which achieves the above object, is buried by inserting a container containing waste into a burial hole formed in rock. At this time, a mixture of aggregate, fibrous reinforcing material such as glass fiber and bentonite is formed into a predetermined shape by compression molding, which is interposed between the inner surface of the burial hole and the outer surface of the container. It is characterized by being constituted.

[0009] The fibrous reinforcing material is characterized in that the fibrous reinforcing material is intensively mixed in a high tensile force acting portion.

[0010]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is an external perspective view of a water impermeable buffer material for embedding waste according to the present invention, and FIG. 2 is a cross-sectional view showing an embedded state of a waste storage container which is a usage mode of the water impermeable buffer material.

The illustrated water-impervious cushioning material 10 is composed of a hollow-bottomed cylindrical main body 11 opening upward and a disk-shaped lid 12 closing the opening, and as shown in FIG. The mixture is formed by compressing and molding a mixture of gravels and silica sand as a material and glass fibers as a fibrous reinforcing material, so that glass fibers are mixed into the whole.

In the compression molding, as shown in FIG. 4, an example of the main body 11 is filled in a cavity 21 formed of an elastic material such as rubber with a mixture 20 obtained by mixing bentonite with aggregate and glass fiber. Core 2 corresponding to the empty part
2 is inserted and the hydraulic pressure is uniformly applied to the outer surface from the outside of the cavity 21.

[0013] The impermeable cushioning material 10 thus configured is
As shown in FIG. 2, the main body 1 is inserted into a buried hole 2 formed in the ground 1.
After the waste storage container 3 is inserted into the hollow portion of the main body 11, the lid 12 is disposed so as to cover the opening of the main body 11. Inner peripheral surface of hollow portion of main body 11 and waste container 3
Is filled with bentonite to form a bentonite layer 4.

As described above, the water-impervious cushioning material 10 in which the glass fiber as the fibrous reinforcing material is mixed has a high tensile strength due to the glass fiber, and is hard to be broken. Can be prevented. That is, in the shape of the main body 11 of this configuration example, when the upper part is supported and lifted, the maximum stress is generated on the side wall part near the bottom part, and if the glass fiber is not mixed, the part is easily broken at the part. Although transport is difficult, this configuration does not have such a risk and can be transported easily. Further, since the strength is improved by the glass fiber, the content of bentonite can be reduced, and the cost can be reduced.

The above configuration example is an example in which glass fiber is used as the fibrous reinforcing material. However, the fibrous reinforcing material is not limited to this, and other fibers such as carbon fiber may be used. .

Also, an example has been shown in which the fibrous reinforcing material is mixed into the entire water-impervious cushioning material. However, as shown in the main body 11 'of FIG. The material may be selectively mixed. That is, when filling the cavity with the mixture at the time of molding, by positioning the mixture in which the fibrous reinforcing material is mixed in the bottom corner 11A, it is possible to reinforce only a portion where a large stress acts. . According to this, reinforcement can be more efficiently performed as compared with the case where a fibrous reinforcing material is mixed in the whole, and it can contribute to cost reduction.

Further, the shape of the water-impervious buffer material is not limited to the shape of the above-described configuration example, but can be set as appropriate. Is also good.

[0018]

As described above, according to the impermeable buffer material for burying waste according to the present invention, the mixture of the aggregate, the fibrous reinforcing material and the bentonite is formed into a predetermined shape in advance by compression molding. By doing so, the tensile strength can be improved and breakage during transfer can be prevented. Therefore, it is possible to use a product integrally formed in a desired shape, and it is possible to improve workability.

Further, by improving the strength, the content of bentonite can be reduced, and the cost can be reduced.

Further, since the fibrous reinforcing material is intensively mixed into the high tensile force acting portion, the cost can be further reduced.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a water impermeable buffer material for burying waste according to the present invention.

FIG. 2 is a cross-sectional view showing an embedded state of a waste storage container, which is a usage mode of a water-impeding buffer material.

FIG. 3 is a view showing a manufacturing process of a water-impervious cushioning material.

FIG. 4 is a view showing a step of forming a water-impervious buffer material.

FIG. 5 is a cross-sectional view of a different configuration example of a water-impervious cushioning material.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 rock 2 burial hole 3 waste container 10 water barrier material (water barrier material for waste burial) 11 body (water barrier material for waste burial) 11 'body (water barrier material for burial waste) 11A Bottom corner (high tensile force action area) 12 Lid (impervious buffer for burying waste)

Claims (3)

[Claims] When a container containing waste is inserted and buried in a burial hole formed in a bedrock, the container is interposed between an inner surface of the burial hole and an outer surface of the container. A water impermeable buffer material for burying waste, wherein a mixture of aggregate, fibrous reinforcing material and bentonite is formed into a predetermined shape by compression molding in advance. 2. The impermeable cushioning material for burying waste materials according to claim 1, wherein the fibrous reinforcing material is configured to be concentrated and mixed in a portion where high tensile force acts. 3. The impermeable buffer material for burying waste materials according to claim 1, wherein the fibrous reinforcing material is glass fiber.