JP2013057189A - Soil surface decontamination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a soil surface decontamination device which allows water and soil to be reutilized on site.SOLUTION: A soil surface decontamination device which removes a contaminant deposited on a soil surface for decontamination comprises a soil surface collecting part 100 including a water injection part 102 which injects water to the soil surface to form a flow of slurry of a mixture of soil and water and a slurry pan part 103 which receives the slurry flow, and a soil decontamination part 200 including a separation part 204 which separates the slurry in the slurry pan part 103 into water and soil and a decontamination part 209 which removes the contaminant from the separated water.

Description

  The present invention scrapes the surface of contaminated soil with a water jet and separates and decontaminates the contaminants from the collected water and soil mixture, thereby reusing the separated water and soil in situ. The present invention relates to a soil surface decontamination apparatus that makes it possible.

  When a pollutant existing inside a specific facility is released into the atmosphere due to a natural disaster or the like, the pollutant diffuses within a certain area around the facility and accumulates on the soil surface. In this case, an operation for removing contaminants from the surrounding soil surface, a so-called decontamination operation is performed.

  In the conventional soil decontamination work, for example, the work of scraping the soil surface with a bulldozer or the like is performed. However, in such work, it is necessary to secure a transportation and storage place for disposal of the shaved soil. In reality, the scraped soil is piled up at one corner of the place where the decontamination work was performed, and the vinyl is piled up. It is often left with a sheet. In addition, it is necessary to transport and spread new soil to supplement the shaved soil from another location.

  Moreover, although it is not the soil surface, there exists an apparatus which collects earth and sand by injecting water on the road surface as an apparatus which collects the earth and sand on the road surface (for example, refer patent document 1).

JP2009-7823

  However, in the apparatus of Patent Document 1, water and earth and sand are separated, but contaminants are not separated. For this reason, when the soil surface is contaminated with contaminants, the collected soil and water cannot be reused. Therefore, it is necessary to isolate and store the collected soil by placing a blue sheet on the corner of the ground, for example, and to separate and store the water in a separate tank.

  The present invention has been made to solve such a conventional problem, and intends to provide a soil surface decontamination apparatus that enables reuse of water and soil on the spot while decontaminating the soil. Is.

  The present invention is a soil surface decontamination apparatus that removes contaminants accumulated on the soil surface and decontaminates the water, sprays water onto the soil surface, and generates a slurry flow in which soil and water are mixed, A soil receiving portion having a slurry receiving portion for receiving the slurry flow; a separation portion for separating the slurry in the slurry receiving portion into water and soil; and a decontamination portion for removing contaminants from the separated water. And a soil decontamination part.

  According to the soil surface decontamination device of the present invention, the collected water and soil are decontaminated, so that the water and soil can be reused. In addition, since the contaminants are only decontamination filters, the disposal of the contaminants becomes easy.

It is a figure which shows the soil surface decontamination apparatus of embodiment of this invention. It is a perspective view which shows the structure of the soil surface collection | recovery part of embodiment of this invention. It is a figure which shows operation | movement of the soil surface collection | recovery part of embodiment of this invention.

  Hereinafter, a soil surface decontamination apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. In the following explanation, the decontamination of the soil surface will be described as an example, but the present invention is not limited to this, and it can be applied to a surface on which pollutants such as roads, concrete, and asphalt are widely deposited. is there.

  FIG. 1 is a diagram illustrating a soil surface decontamination apparatus according to an embodiment of the present invention. As shown in the figure, the soil surface decontamination apparatus 1 of this embodiment is configured to be mounted and installed on a truck. Thereby, the soil surface decontamination apparatus 1 of this embodiment can move the contaminated soil surface arbitrarily.

  The soil surface decontamination apparatus 1 according to the present embodiment includes a soil (etc.) surface sampling unit 100 provided in front of the truck cab 2 and a soil decontamination unit 200 provided in the truck bed. . In this embodiment, the set of devices is loaded on a truck, but for example, the collection of the slurry can be separated by loading the slurry until the collection of the slurry and loading the subsequent system on another truck. Miniaturization is possible.

(Configuration of soil surface sampling unit)
The soil surface collection unit 100 according to the present embodiment includes a rake unit 101, a water jet tube 102, and a slurry tray unit 103.

  FIG. 2 is a perspective view showing the configuration of the soil surface collection unit 100 of the present embodiment. The rake portion 101, the water jet tube 102, and the slurry tray portion 103 are attached to the cab 2 by arms 104, 105, and 106, respectively. By swinging the arms 104, 105, 106, the height adjustment (clearance adjustment) of the rake portion 101, the water injection pipe 102, and the slurry receiving tray portion 103 with respect to the soil surface can be performed, and upward when not in use. It is also possible to evacuate.

  One end of a pipe P2 is connected to the water injection pipe 102, and a flow rate adjusting pressure pump 216, which will be described later, is connected to the other end of the pipe P2 and communicates with each other. One end of the pipe P1 is connected to the slurry tray 103, and a slurry recovery air vacuum pump 201 described later is connected to the other end of the pipe P1 and communicates with each other.

  FIG. 3 is a diagram illustrating the soil surface collection unit 100 of the present embodiment. As shown in FIG. 3, the rake unit 101 includes a plurality of rake blades 101 a, and when the rake unit 101 descends, the tip of the rake blade 101 a pierces the soil surface to plow the soil. The water injection pipe 102 is a substantially hollow pipe and includes a plurality of injection nozzles 102a, and water from the flow rate adjusting pressure pump 216 is injected from the injection nozzle 102a onto the soil surface. The slurry receiving tray 103 is a substantially plate-shaped member, has a projection 103a that dams up the recovered slurry in front of the slurry receiving tray 103, and has a container shape for receiving the recovered slurry behind it.

(Configuration of soil decontamination unit)
Returning to FIG. 1, the soil decontamination unit 200 of this embodiment includes a slurry recovery air vacuum pump 201, a slurry recovery tank 202, a slurry pump 203, a decanter centrifuge 204, a vortex pump 205, a recovery soil storage unit 206, a contamination Includes a water tank 207, a pressure pump 208, a decontamination filter 209, a temporary water storage tank 210, an extraction valve 211, a contamination monitor 212, a valve 213, a vortex pump 214, a water tank 215, and a flow rate adjustment pressure pump 216. Consists of.

  The slurry collection air vacuum pump 201 is connected to the slurry tray 103 via the pipe P 1 and is provided in the slurry collection tank 202. In this specification, the slurry is defined as a fluid in which water, contaminants, and soil are mixed. The air vacuum pump includes an ejector having a first insertion port connected to a compressed air generator such as a compressor and a second insertion port connected to the slurry recovery tank 202, and the compressed air is supplied to the first insertion port of the ejector. By inserting and discharging air from the discharge port of the ejector, negative pressure is generated in the slurry collection tank 202 and the slurry is sucked.

  The slurry pump 203 is connected to the slurry collection tank 202, and sends the slurry in the slurry collection tank 202 to the decanter centrifuge 204 through a pipe.

  The decanter centrifuge 204 centrifuges the slurry to separate it into water and soil. The centrifugation method is not limited to the decanter type, and a disk type or the like may be used.

  The vortex pump 205 is connected to the decanter centrifuge 204 via a pipe, and sends the water separated by the decanter centrifuge 204 to the contaminated water tank 207 via the pipe.

  The recovered soil storage device 206 is connected to the decanter centrifuge 204 through a pipe, and temporarily stores the soil separated by the decanter centrifuge 204.

  The contaminated water tank 207 is a tank that temporarily stores the contaminated water, and the contaminated water in the contaminated water tank 207 is sent to the decontamination filter 209 via the piping by the pressure pump 208.

  The decontamination filter 209 removes contaminants from the contaminated water and generates purified water. For the decontamination filter 209, for example, a reverse osmosis membrane filter type water purifier can be used. By using a reverse osmosis membrane filter, radioactive substances such as iodine, cesium, and strontium can be removed.

  The temporary water storage tank 210 is connected to the decontamination filter 209 via a pipe, and temporarily stores the water purified by the decontamination filter 209.

  The extraction valve 211 is provided in a pipe between the temporary water storage tank 210 and the contamination monitor 212, and can extract water to the outside. When it is confirmed by the contamination monitor 212 described later that contamination remains, decontamination is performed again through the decontamination filter 209.

  The contamination monitor 212 is a device for measuring the degree of contamination of water from the temporary water storage tank 210, and checks whether or not the decontaminated water can be treated as normal water (uncontaminated water). If the pollutant is a radioactive substance, a dosimeter can be used for the pollution monitor 212.

  The valve 213 is provided in a pipe between the contamination monitor 212 and the vortex pump 214, and can shut off the water from the contamination monitor 212 and make it conductive.

  The vortex pump 214 sends the water in the temporary water storage tank 210 to the water tank 215 via the contamination monitor 212, the valve 213, and the piping.

  Purified water is stored in the water tank 215, and the purified water is sent to the water injection pipe 102 via the pipe P 2 by the flow rate adjusting pressure pump 216.

(Device operation)
Next, the procedure of the decontamination method by the soil surface decontamination apparatus of this embodiment is shown. In this embodiment, land mainly composed of flat soil is targeted. In this embodiment, a radioactive substance will be described as an example of a contaminant in particular, but the contaminant is not limited to this, and the apparatus can be used as long as it removes a contaminant that does not chemically react with soil. .

  First, the contamination state of the surface of the land to be decontaminated is measured. Dosimeters are used in case of contamination by radioactive material. And the surface hardness of land is measured using a digital soil hardness meter. Next, dig the land locally and measure the pollution depth.

  FIG. 3 is a diagram illustrating the operation of the soil surface collection unit 100 of the present embodiment. According to the measured contamination depth, the digging depth by the tip of the rake blade 101a of the rake portion 101 is adjusted by the arm 104, and the land is plowed from the flat surface D to the tillage surface E to a fixed depth.

  Next, according to the depth of the cultivating surface E dug by the rake part 101, the angle and water pressure of the spray nozzle 102a of the water spray pipe 102 are adjusted and sprayed (A in the figure), and water and soil are mixed. Roll up the slurry (B in the figure). The slurry that bounces up at that time is received and collected by the slurry tray 103 (C in the figure). For example, since radioactive substances such as radioactive iodine and radioactive cesium are water-soluble, the radioactive substance dissolves in water when the slurry is rolled up with water, so that the pollutant can be efficiently recovered.

  Instead of digging with the rake portion 101, the water injection angle and water pressure of the injection nozzle 102a are adjusted according to the hardness of the soil, and when digging deeper, the angle to the soil is increased from the horizontal to the right angle, or Alternatively, the water pressure may be increased and decontaminated up to a certain depth.

  The slurry collected in the slurry receiving tray 103 is accumulated in the slurry collection tank 202 by the slurry collection air vacuum pump 201 and further moved to the decanter centrifuge 204 by the slurry pump 203.

  In the decanter centrifuge 204, the slurry is separated into water and soil. Since radioactive substances such as radioactive iodine and radioactive cesium are water-soluble, pollutants are transported to the next process together with water, and soil is decontaminated at this point.

  The water separated by the decanter centrifuge 204 is sent to the decontamination filter 209 via the vortex pump 205, the contaminated water tank 207, and the pressure pump 208, and the water is decontaminated. If the decontamination is insufficient as a result of the inspection by the contamination monitor 212, recontamination is performed. In addition, the filter used for decontamination is treated as a contaminant according to the degree of contamination.

  The soil separated by the decanter centrifuge 204 is collected in the collected soil storage device 206 and returned to the surface of the soil that is being decontaminated. Moreover, if it is not necessary to return the soil to the place, it can be stored as it is, or it can be transported to another place and used as normal soil.

  As explained above, according to the soil surface decontamination apparatus of this embodiment, the decontamination of the soil near the soil surface can be performed efficiently. Also, since the soil is returned to its original location, there is no need to transport new soil. In addition, since water can be reused, the water tank can be made smaller and resources can be saved.

  Further, in the conventional decontamination method using a bulldozer, the soil is shaved and removed, so the amount of contaminants becomes very large, which makes it difficult to treat. However, in the soil surface decontamination apparatus of this embodiment, the collected water Since soil is decontaminated and can be reused on the spot, the amount of contaminants is very small with only the filter, and the disposal of the contaminants is easy. Furthermore, soil that has already been cut and collected by a conventional decontamination method using a bulldozer is mixed with water to form a slurry, which is put into the slurry collection tank 202 and processed by the soil surface decontamination apparatus of this embodiment. By decontamination, you can return to the original place. In addition, contaminated sludge generated by sewage treatment and sludge collected in a side ditch etc. and scooped out with a scoop etc. should be decontaminated in the same way by applying to the soil surface decontamination device of this embodiment. Can do.

  Moreover, the soil surface decontamination apparatus of this embodiment is applicable not only to the soil surface but also to grassland. That is, after cutting the grass or removing the grass from the roots, it is possible to do the same.

1: Soil surface decontamination apparatus 100 of the present embodiment: Soil surface sampling unit 101: Rake unit 102: Water jet tube 103: Slurry receiving unit 200: Soil decontamination unit 201: Slurry recovery air vacuum pump 202: Slurry recovery tank 203 : Slurry pump 204: Decanter centrifuge 205: Swirl pump 206: Recovery soil storage 207: Contaminated water tank 208: Pressurized pump 209: Decontamination filter 210: Temporary water storage tank 211: Extraction valve 212: Contamination monitor 213 : Valve 214: Centrifugal pump 215: Water tank 216: Flow rate adjusting pressure pump

Claims (5)

A soil surface decontamination device that removes and decontaminates contaminants deposited on the soil surface,
A water injection unit for injecting water onto the soil surface and generating a slurry flow in which soil and water are mixed; and
A slurry pan for receiving the slurry stream;
A soil surface collection unit having
A separation part for separating the slurry in the slurry receiving part into water and soil;
A decontamination section for removing contaminants from the separated water;
A soil decontamination part,
A soil surface decontamination apparatus comprising:   The soil surface decontamination apparatus according to claim 1, wherein water decontaminated in the decontamination unit is sent to the water injection unit and reused as water for injection.   The soil surface decontamination unit according to claim 1 or 2, wherein the soil decontamination unit further includes a collected soil storage unit that returns the soil separated by the separation unit to the surface of the soil and reuses it. apparatus.   The soil surface decontamination device according to any one of claims 1 to 3, wherein the soil surface collection unit further includes a rake unit that plows the soil before the water injection unit injects water. 5. The soil surface decontamination apparatus according to claim 1, wherein the soil surface collection unit is provided in front of a cab of the vehicle, and the soil decontamination unit is mounted on the vehicle.

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