JP5653063B2 - Soil improvement method - Google Patents

Description

  The present invention is to improve contaminated soil, which is soil contaminated with chemical substances such as heavy metals, oils, dioxins, volatile organic compounds (VOC), pesticide residues, and persistent organic pollutants (POPs). It relates to the soil improvement method.

  If a building is built on contaminated soil such as a factory site contaminated with chemical substances, the chemical substances contained in the contaminated soil may cause health damage to those who use the building. . For example, the Law Concerning Soil Contamination Countermeasures is a law whose main purpose is to prevent the occurrence of such health damage, but it is not difficult to imagine that even without such a law, it is necessary to purify contaminated soil. I will.

Conventional cleaning of contaminated soil is realized by the following soil improvement method.
In the conventional soil improvement method, first, the space above the improvement range to be improved in the contaminated soil is airtightly covered with the first film material having a predetermined shape, and is covered with the first film material. Negative pressure. Further, adjacent to the first film material, the space above the predetermined range adjacent to the improved range is hermetically covered with the second film material having a predetermined shape, and the space covered with the second film material is covered. Negative pressure.
In that state, the soil is dug from the improved range in the space covered with the first film material. Then, the excavated soil is packed in a sealable container and conveyed from the space covered with the first film material to the space covered with the second film material. Next, in the second space, the chemical discharged from the container in the large tray is mixed with chemicals to be treated by decomposing, adsorbing, or immobilizing chemical substances contained in the contaminated soil, and after stirring. Leave for a while. In addition, mixing of a chemical | medical agent may be performed simultaneously with discharging soil from a container to a large sized tray. The soil is then transferred again from the large tray to a sealable container and shipped to be transported to a disposal facility that disposes of contaminated soil.

In the soil improvement method as described above, the main work is performed inside the space covered with the first membrane material and the airtight space covered with the second membrane material. Can be prevented. Therefore, there is an advantage that it can be implemented even in an environment where there are people in the vicinity.
However, the space required by the above-mentioned soil improvement method is usually made by a huge tent, but in the conventional soil improvement method, the space covered with the first film material and the second Since two airtight spaces, the space covered with the membrane material, are required, it takes time, cost and cost to set up two huge tents.

  This invention makes it the subject to improve the soil improvement construction method for improving a contaminated soil so that effort, time, and cost may become advantageous.

The present inventor proposes the following soil improvement method as an invention for solving such a problem.
In the soil improvement method of the present invention, the space above the improvement range to be improved among the contaminated soil contaminated with chemical substances is airtightly covered with a film material of a predetermined shape and covered with the film material. The process of negative pressure in the space, the process of sealing the container after filling the container excavated from the improved range in the space with a chemical that treats the chemical substance in a container that can be sealed, The process of stirring the soil and the drug inside the container carried out from the space covered with the membrane material together with the container, for transporting the stirred container to a disposal facility that disposes contaminated soil Including the process of shipping to.
In this soil improvement method, the above-described stirring process, which has been performed in an airtight space covered with the second film material, is performed in a sealable container. Is unnecessary. Therefore, in this soil improvement method, the second film material and the airtight space covered by the second film material are not required, so that labor, time, and cost are advantageous as compared with the conventional soil improvement method.
As described above, the agent in the present invention treats chemical substances contained in contaminated soil. The term “treatment” used herein refers to heavy metals, oils, dioxins, VOCs, contained in contaminated soil. This means general treatment for preventing at least one of residual pesticides and POPs from flowing out by decomposing, adsorbing, or immobilizing them.

  The container used in the present invention can be sealed as described above. Although details are not ask | required if it is such a container, a drum can can be used as a container, for example. This will increase the cost advantage.

In this invention, the said soil and chemical | medical agent are stirred with the said container. The agitation of soil and chemicals for each container may be done in any way. The container may be shaken in a predetermined direction such as up and down, left and right, the container may be rotated, or a combination thereof may be used. Of course, any device or apparatus may be used for stirring the container.
For example, when a drum can is used as the container, the drum can be detachably attached to rotate the container, and the attached drum can be rotated while reversing its top and bottom. An apparatus can be used.
In the case of using the stirring device as described above, a non-airtight tent for preventing the stirring device from rain can be further provided. Since the tent in this case does not need to be airtight, the labor, time, and cost for its setup can be reduced. The tent may be a simple structure that supports a horizontal roof with four pillars, for example.

The figure which shows roughly the equipment used with the soil improvement construction method by one Embodiment of this invention. The figure for demonstrating the operation | work performed in the airtight tent shown in FIG. The figure for demonstrating the operation | work performed in the simple tent shown in FIG.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 schematically shows equipment used in the soil improvement method of this embodiment.
In the soil improvement method of this embodiment, an airtight tent 1 and a simple tent 2 are used although not essential.

The airtight tent 1 is a tent having a floor surface open so as to maintain airtightness as a whole, and can be realized by a conventionally used highly airtight tent. The airtightness of the airtight tent 1 is not limited as long as dust of contaminated soil generated by the work described later performed in the airtight tent 1 does not leak out from the airtight tent 1.
The airtight tent 1 is built on contaminated soil contaminated with chemical substances. The contaminated soil exposed in the portion corresponding to the floor surface of the airtight tent 1 is the improved range in this application.
The airtight tent 1 of this embodiment includes columns and beams not shown in the figure, and a film material 11 that covers the columns and beams. Although the beam is not necessarily limited to this, in this embodiment, the beam is a metal pipe, and the film material 11 is a resin sheet material. The shape of the airtight tent 1 is not necessarily as shown in the figure, but is required to have a shape and size that can perform the work described later.
An air intake device 13 is connected to the airtight tent 1 through a tube 12. The intake device 13 sucks air in the airtight tent 1 through the tube 12 and discharges the sucked air through a filter (not shown) to the outside. The inside of the airtight tent 1 is made negative pressure by the intake device 13. Such negative pressure prevents the dust from the contaminated soil from leaking out of the airtight tent 1 to the outside caused by the work to be described later performed in the airtight tent 1.

The simple tent 2 is provided adjacent to the airtight tent 1. In this embodiment, the simple tent 2 has a very simple configuration in which a film material 22 is stretched over four columns 21. Under the membrane material 22 of the simple tent 2, the stirring device 3 is placed. The simple tent 2 is of a level that prevents the stirrer 3 placed outdoors from raining.
The column 21 and the film material 22 constituting the simple tent 2 of this embodiment are a metal pipe and a resin sheet material, respectively. The shape of the simple tent 2 does not necessarily have to be as illustrated, but the shape and size are such that the stirring device 3 can avoid rain.
As will be described later, the simple tent 2 may be a place for drums. In that case, the simple tent 2 has a shape and a size that can prevent the drum can from raining.

The soil improvement method of this embodiment is performed as follows.
In this soil improvement method, first, the contaminated soil is dug inside the airtight tent 1 and packed in a drum can D as shown in FIG. The drum D may be very common.
The excavation of the contaminated soil and the filling into the drum D can be performed manually or using heavy equipment.
In addition to the contaminated soil, the drum D is filled with chemicals and, if necessary, water. A chemical | medical agent processes the chemical substance which is contaminating the contaminated soil (it decomposes | disassembles, adsorb | sucks or fix | immobilizes), and can be suitably selected according to the chemical substance contained in the contaminated soil. Chemical substances contained in contaminated soil include heavy metals, oil, dioxins, VOCs, residual agricultural chemicals, and persistent organic pollutants (POPs). For example, if contaminated soil contains heavy metals, immobilize heavy metals. A known chelating agent can be used as a drug. The charcoal powder can adsorb oil and the like. Microorganisms that degrade oils, dioxins, VOCs, pesticide residues, and POPs are also known, but the drug may contain such microorganisms. The water added to the drum can D as needed together with the medicine is for softening the contaminated soil packed in the drum can D, so that the contaminated soil and the medicine are well mixed when the agitation described below is performed. is there. Water is not necessary when the medicine contains a lot of water. In addition, the medicine and water may be mixed in advance.
In this embodiment, the medicine is preliminarily mixed with water at a predetermined ratio, and is poured into the drum can D from a tank (not shown) using a hand gun. However, how to pack the medicine and water in the drum D may be appropriately selected.
Once the contaminated soil, chemicals, and water as needed are packed into the drum D, the lid D1 is fitted into the drum D. As a result, the drum D is sealed.

  The drum D in which the contaminated soil, the drug, and water are sealed in a sealed state is carried from the airtight tent 1 to the simple tent 2. The drum D may be carried by any method.

In the simple tent 2, the contaminated soil enclosed in the drum can D and the chemical are agitated. For the stirring, the above-described stirring device 3 is used.
The agitating device 3 has a function of uniformly mixing the contaminated soil and the drug inside the sealed drum can D by shaking, reciprocating, or rotating the drum can D. Examples of the stirring device having such a function include “Drum Shaker” (trademark / product number: DS-200S) manufactured by Seiwa Giken Co., Ltd., “Hoop Shaker” (trademark / product number: SDHS-200) manufactured by Shiro Sangyo Co., Ltd. Since there is “Mazemaze Man” (trademark / product number: SKH-3000) of the company Misugi, the stirring device 3 may be used.
The stirrer 3 of this embodiment includes a main body 31, a shaft bar 32, and a fixed part 33, as schematically shown in FIG. The main body portion 31 is placed on the ground surface, and has a sufficiently stable weight and a highly stable shape even when the drum can D is fixed by the fixing portion 33 as will be described later. In addition, a drive device (not shown) which will be described later is built inside. The shaft rod 32 is a rod having a base end connected to the driving device inside the main body 31 and a tip connected to the fixed portion 33. The fixing part 33 is configured in a ring shape. The diameter of the fixing portion 33 is slightly larger than the diameter of the drum can D in a normal state, but can be slightly reduced as necessary. The fixing portion 33 can fix the drum can D by reducing the diameter in a state where the drum can D is inserted into the inner opening. The fixing of the drum can D by the fixing portion 33 is a detachable one that can be released by returning the diameter of the fixing portion 33 to a normal state.
When stirring is performed, the drum can D is fixed to the fixing portion 33 as shown in FIG. Then, the drum can D is in a suspended state. In this state, the driving device rotates the shaft 32 around the axis. Then, the drum D rotates while reversing the top and bottom, and the contaminated soil in the drum D and the medicine are mixed uniformly.
After stirring, the drum can D is shipped for transport to a disposal facility that disposes of contaminated soil. For example, when there is a time until such shipment is performed, or when it takes time for the medicine to be effective in the drum can D, the drum can D is placed under the membrane material 22 of the simple tent 2. It is possible to leave. Of course, it is possible to place the drum D before stirring under the membrane material 22 of the simple tent 2.

1 Airtight tent 2 Simple tent 3 Stirrer D Drum

Claims (5)

A process of airtightly covering a space above the improvement range of the contaminated soil contaminated with a chemical substance with a film material of a predetermined shape, and depressurizing the space covered with the film material ,
Among the space, in a container portable was dug from the improved range soil sealable and on its own, after filled with an agent for processing the chemical process of sealing the container,
The process of stirring the soil and the drug inside the container carried out from the space covered with the membrane material together with the container,
A process of shipping the agitated container for transportation to a disposal facility for disposal of contaminated soil;
Including soil improvement method. A drum can is used as the container.
The soil improvement construction method according to claim 1. In the process of stirring the soil and chemicals together with the container, the container is rotated.
The soil improvement construction method according to claim 1. While using a drum as the container,
In order to rotate the container, a drum can be detachably attached, and a predetermined stirring device capable of rotating the attached drum can while reversing its top and bottom is used.
The soil improvement construction method according to claim 1. Further providing a non-tight tent to prevent the stirring device from raining,
The soil improvement construction method according to claim 4.

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