JP2003340428A - Cleaning construction method for contaminated ground and water circulator used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning construction method for contaminated ground capable of cleaning the entire part of the contaminated ground by uniformly circulating water in the contaminated ground, and a water circulator used for this construction method. <P>SOLUTION: Water circulating pipes 2 of the water circulator 100 provided with a plurality of expandable packers 3 disposed apart prescribed intervals in the depth direction of draw wells DW and injection wells IW and a plurality of water flow ports 7 formed between the packers 3 to inject or suck the water into or from the contaminated ground G are respectively inserted into the injection wells IW and the draw wells DW. The packers 3 are expanded to compartmentalize the contaminated ground G to multiple stages in the depth direction and the water cleaned in a pollution treatment apparatus 9 is injected into the ground G from the ports 7 of the pipes 2 inserted into the injection wells IW and the water in the ground G is sucked from the ports 7 of the pipes 2 and is sent to the apparatus 9, by which the water is circulated in the routes independently by each of the ground stages G compartmentalized to the multiple stages and the contaminated ground G is cleaned. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a purification method for purifying contaminated ground by circulating water purified by a pollution treatment device in the contaminated ground, and a water circulation device used in this method.

[0002]

2. Description of the Related Art In recent years, it has become a serious problem that harmful substances such as organochlorine compounds and heavy metals are accumulated in the ground due to landfilling of waste materials and leakage of factory wastewater, etc. Therefore, as a measure against pollution of contaminated ground, conventionally, the water contained in the contaminated ground is pumped to the ground to be purified, and the purified water is circulated again by returning the purified water to the ground. Purification methods for purification have been proposed.

8 and 9 are views showing a cleaning device for carrying out a conventional method for cleaning contaminated ground, FIG. 8 is a side view of the same, and FIG. 9 is a plan view of the same. In FIG. 8, G is a contaminated ground contaminated with a harmful substance, and contains water in which the harmful substance is dissolved in the ground G. DW is a pumping well provided by excavating the contaminated ground G to a predetermined depth.
As shown in, a plurality of them are arranged on the contaminated ground G. This pumping well DW is a well for pumping the water that has permeated into the pumping well DW from the ground G to the pollution treatment device C by the pump P provided at the bottom. IW is a water injection well provided by excavating the contaminated ground G to a predetermined depth, and as shown in FIG. 9, a plurality of IWs are arranged in the contaminated ground G around the plurality of pumping wells DW. The water injection well IW is a well for injecting into the ground G water that is pumped from a pollution treatment device C installed on the ground by a pump (not shown) provided inside the pollution treatment device C. In addition to the pumps described above, the pollution control device C is composed of a heavy metal ion treatment device, an organic matter / microorganisms treatment device, a wastewater treatment device, a water replenishment device, etc., and purifies water through the pumping well DW to these devices. Then, the purified water is pumped to the water injection well IW. In addition, the pollution control device C
The purified water contains microorganisms that decompose harmful substances, nutrients that activate these microorganisms, agents that promote separation of harmful substances from the ground G, and chemical agents that cause chemical reactions with harmful substances to render them harmless. ing. L1 and L2 are the water levels of the water in the contaminated ground G, and the arrows show the flow of water.

In the above structure, when the water purified by the pollution treatment device C is pumped into the water injection well IW, the water is injected from the water injection well IW into the contaminated ground G and, at the same time, into the contaminated ground G. The contained contaminated water permeates into the pumping well DW due to the head difference between the injection well IW and the pumping well DW.
Then, the water that has permeated into the pumping well DW is pumped up to the pollution treatment device C by the pump P, is purified inside the pollution treatment device C, is pumped to the water injection well IW, and is injected into the contaminated ground G again. It When water is reinjected into the contaminated ground G from the water injection well IW in this way, the previously injected water releases microorganisms into the contaminated ground G or harmful substances are released into the ground G.
While permeating through the soil, it penetrates into the contaminated ground G and seeps into the pumping well DW again. Then, the water that has soaked into the pumping well DW is again pumped up to the pollution treatment device C by the pump P, purified, and then pumped to the water injection well IW and injected into the contaminated ground G. Therefore, by continuously circulating the water as described above, the harmful substances contained in the contaminated ground G are gradually removed and the contaminated ground G is gradually purified.

[0005]

However, in the conventional method for cleaning the contaminated ground G, the water injected from the injection well IW permeates the contaminated ground G due to the head difference between the water injection well IW and the pumping well DW. Then, the water permeates into the pumping well DW and is pumped up by the pump P installed at the bottom of the pumping well DW, so that water is pumped from the injection well IW to the pumping well DW.
Pumping well D without penetrating horizontally into the contaminated ground G
Permeate around W in the direction toward pump P in pumping well DW. For this reason, the water level in the contaminated ground G was initially the same level L1 around the water injection well IW and around the pumping well DW. The water level becomes L2, which drops in the vicinity,
There is a problem that water cannot be circulated in the contaminated ground G above the water level L2 and the contaminated ground G above this cannot be purified. When a layer such as a gravel layer where water easily penetrates and a layer such as a clay layer where water hardly penetrates are distributed in the depth direction of the contaminated ground G, the water is gravel layer. Focus on the layer that is easy to penetrate and penetrate,
Since it circulates, there is a problem that the entire contaminated ground G cannot be purified.

The present invention is intended to solve the above-mentioned problems, and its object is to purify a contaminated ground by uniformly circulating water in the contaminated ground and purifying the entire contaminated ground. And to provide a water circulation device used in this method.

[0007]

According to the method for purifying contaminated ground according to the present invention, a plurality of expandable packers provided at predetermined intervals in the depth direction of a pumping well and a water injection well, and between the packers are formed. And a water circulation device with a plurality of water inlets for injecting or sucking water into the contaminated ground,
By inserting each into the water injection well and the pumping well and expanding the packer, the contaminated soil was divided into multiple stages in the depth direction, and was purified by the pollution treatment device from the water inlet of the water circulation device inserted in the water injection well into the ground. By injecting water and sucking the water in the ground from the water inlet of the water circulation device inserted in the pumping well and sending it to the pollution control device, the water can be circulated through independent paths for each ground divided into multiple stages. Purify contaminated ground.

[0008] By doing so, the water purified by the pollution control device is circulated by an independent path for each of the grounds divided into multiple stages in the depth direction by the packer, so that the water level in the ground is pumped up. Water can be uniformly circulated in the contaminated ground while maintaining the same level of water level from the injection well to the pumping well without lowering the water around the well, and the entire contaminated ground can be purified. Also,
Purified water is injected from the water inlet of the water injection well for each ground divided by the packer in multiple stages, and the water in each ground is sucked from the water inlet of the pumping well.
The penetration speed of water that penetrates into each ground becomes faster,
It is possible to circulate water quickly and shorten the period for cleaning contaminated ground.

Further, in the method for purifying contaminated ground according to the present invention, water purified by the pollution control device is injected into the ground through the filter from the water inlet of the water circulation device inserted in the water injection well, and the water is pumped into the pumping well. From the water inlet of the inserted water circulation device, it is preferable to suck the water in the ground through a filter.

By doing so, it is possible to prevent sand, gravel, etc. contained in the water in the ground from being filtered by the filter and intruding into the inside of the water circulation device through the water inlet of the water circulation device inserted in the pumping well. Therefore, it is possible to constantly and stably inject and suck water from the water inlet of the water circulation device inserted in the water injection well or the pumping well.

Further, in the method for purifying contaminated ground according to the present invention, the water purified by the pollution treatment device is injected into the ground at a low pressure from the water inlet of the water circulation device inserted in the water injection well, and the water is inserted into the pumping well. It is preferable to naturally suck the water in the ground through the water passage of the water circulation device. In addition, the natural suction is to lower the atmospheric pressure inside the water inlet than the atmospheric pressure in the ground outside the water inlet, and to naturally move the water in the ground from the water inlet to the pollution control device by this pressure difference. Is.

By doing so, the water injected at a low pressure from the water inlet of the water circulation device inserted into the water injection well gradually permeates into the entire ground divided by the packer in multiple stages, and the entire ground is spread. The infiltrated water gathers around the water inlet of the water circulation device inserted in the pumping well and naturally moves to the pollution treatment device, so that water can be evenly circulated to every corner of each ground. , Can be purified.

Further, in the method for purifying contaminated ground according to the present invention, a plurality of water injection wells are provided in the contaminated ground, and a plurality of pumping wells are provided so as to surround each of the plurality of water injection wells.
It is preferable to insert a water circulation device in each of the water injection well and the pumping well.

By doing so, the water injected from a plurality of water injection wells can be circulated in the ground around the water injection well, so that the contaminated ground can be purified over a wide range, and Since a wide range of purification work can be performed at one time, the work period can be shortened.

Further, in the method for purifying contaminated ground according to the present invention, an injection step of injecting the water purified by the pollution treatment device into the ground from the water inlet and a suction step of sucking the water in the ground from the water inlet. And may be alternately switched by water circulating devices inserted in the water injection well and the pumping well.

[0016] By doing so, the directions of water infiltrating into the respective grounds divided by the packer in multiple stages are the direction from the injection well to the pumping well and the direction from the pumping well to the injection well. Since it can be switched to and, water can be circulated evenly in the ground around the water injection well and the pumping well, and purification can be performed. Also, when water is sucked from the water passage through the filter for a long period of time, the filter may be clogged with sand or gravel in the ground, but by doing the above, the filter will be Since the clogged sand, gravel and the like are removed from the filter in the pouring process, the water can be circulated in the ground for a long period of time and can be purified.

Further, the water circulation device used for carrying out the method for purifying the contaminated ground according to the present invention is provided on the outer peripheral surface at a predetermined interval, and expands to divide the contaminated ground into multiple stages in the depth direction. Multiple packers and a plurality of passages for injecting the water formed on the outer peripheral surface between the packers and purified by the pollution control device into the contaminated ground or sucking the water in the contaminated ground and sending it to the pollution control device. A water inlet, a packer expansion passage that is a fluid passage for inflating a plurality of packers, and a water passage that communicates with each of the plurality of water passages and the pollution control device and is injected or sucked from the plurality of water passages. And a plurality of independent water circulation flow paths.

By inserting such a device into each of the water injection well and the pumping well provided in the contaminated ground, the fluid is sent through the packer expansion passage to expand the packer,
The contaminated ground can be divided into multiple stages in the depth direction, and purified water is injected into the ground through the water circulation passage from the water circulation port of the water circulation device inserted into the water injection well, and the water circulation port of the water circulation device inserted into the pumping well. By sucking the water in the ground through the water circulation flow path, it is possible to circulate the water in an independent path for each of the ground divided in multiple stages. As a result, water can be uniformly circulated in the contaminated ground, and the entire contaminated ground can be purified.

Further, the distribution state of strata having different soil properties in the depth direction in the contaminated ground is investigated in advance, and packers are provided at predetermined intervals on the outer peripheral surface of the water circulation device based on the result of the investigation, whereby The contaminated ground can be divided into multiple stages according to the distribution of strata in the depth direction. Then, by circulating water in each soil, water can be uniformly circulated in the entire contaminated soil and can be purified regardless of the distribution state of the stratum in the polluted soil. Furthermore, in order to send the water in the ground from the water inlet of the water circulation device to the pollution treatment device through the water circulation passage for each contaminated soil divided into multiple stages, by checking the degree of contamination of the water passing through each water circulation passage, You can check the degree of purification in the contaminated ground that is divided into
Based on this result, it is possible to circulate the water by adjusting the injection amount and the suction amount of the water and clean the contaminated ground.

Further, in the water circulating apparatus according to the present invention, it is preferable that a plurality of filters are provided so as to cover the outer peripheral surface between the packers, and this filter is provided with a spacer between the outer peripheral surface and the filter.

By providing such a filter, the water injected from the water inlet of the water circulating device inserted in the water injection well is filled in the gap between the outer peripheral surface of the water circulating device formed by the spacer and the filter, and from here Since the water leaks out through the ground to the ground, water can permeate from the entire surface of the filter to the ground in all directions of the water injection well. Also,
The water in the ground that is sucked from the water circulation port of the water circulation device inserted in the pumping well permeates from the entire surface of the filter into the gap between the outer surface of the water circulation device formed by the spacer and the filter, and the permeated water is passed through. Since the water is sucked from the water mouth, sand and gravel in the ground can be prevented from entering the inside of the water mouth, and water can be sucked from the ground in all directions of the pumping well. As a result, it is possible to circulate the water throughout the ground while minimizing the number of water passages formed in the water circulation device, and to efficiently clean the contaminated ground.

Further, the water circulating apparatus according to the present invention preferably comprises a pressure supply source for supplying a pressure necessary for injecting water from the water passage or sucking water from the water passage.

When injecting water from the water inlet or sucking water in the ground for each ground divided into a plurality of stages in the depth direction by the packer, the atmospheric pressure in the ground changes depending on the depth at which the water inlet is arranged. By providing the pressure supply source as described above, it is possible to supply pressure to the water passage and the water circulation path communicating with the water passage according to the depth at which the water passage is arranged, and adjust the air pressure inside these. , It is possible to uniformly inject or suck water from all water passages.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are views showing a water circulation device used for carrying out a method for purifying a contaminated ground according to the present invention. FIG. 1 is a side view of the water circulation device, and FIG.
Is a diagram showing a state in which the water circulation device is installed in the water injection well, FIG.
FIG. 4 is a perspective view showing a filter provided in the water circulation device.

In FIG. 1, reference numeral 100 denotes a water circulation device, which includes a pressure supply source 1 installed on the ground and a water circulation pipe 2 inserted into a water injection well IW provided in a contaminated ground G as shown in FIG. Composed of. The water circulation device 100 is also installed in the pumping well DW provided in the contaminated ground G as shown in FIG. 5, similarly to the water injection well IW. In this case, the same water circulation pipe 2 for the injection well IW and the water circulation pipe 2 for the pumped well DW are used. CL is a center line of the water circulation pipe 2, a cross-sectional view of the water circulation pipe 2 is shown on the right side of the center line CL, and an outline view of the water circulation pipe 2 is shown on the left side. A metal material such as iron or stainless steel is used as the material of the water circulation pipe 2. Reference numeral 3 denotes an inflatable packer, and a plurality of packers 3 are provided on the outer peripheral surface 2a of the water circulation pipe 2 at predetermined intervals in the depth direction of the water injection well IW, as shown in FIG. Therefore, as the packer 3 expands, the contaminated ground G is divided into multiple stages in the depth direction. Moreover, if the predetermined intervals at which the packers 3 are provided are set based on the distribution state of the strata in the depth direction in the polluted ground G that has been investigated in advance, the packer 3 expands, and the polluted ground G becomes different for each stratum with different soil properties. It is divided into multiple stages. As the material of the packer 3, a material such as rubber having corrosion resistance is used.

Reference numeral 2b is an opening formed on the outer peripheral surface 2a of the water circulation pipe 2 so as to communicate with the inside of the packer 3. Reference numeral 4 denotes a fixing metal fitting for fixing both end portions of the packer 3 to the outer peripheral surface 2a of the water circulation pipe 2. If the opening 2b is in a range that allows communication with the inside of the packer 3, the fixing position by the metal fitting 4 is the water circulation pipe 2. It can be freely adjusted in the axial direction. Therefore, the installation position of the packer 3 in the depth direction of the water injection well IW can also be freely adjusted.
Reference numeral 5 denotes a hose having one end connected to the opening 2b and branched so as to communicate with each packer 3, and the other end communicates with a fluid supply source 10 installed on the ground. For this reason,
When the fluid is supplied from the fluid supply source 10 through the hose 5, the fluid enters the inside of the packer 3 through the opening 2b, and the packer 3 expands as shown in FIG. X is a space between the packers 3 formed by the packers 3 expanding and closely contacting the inner surface of the water injection well IW. Hose 5
The opening 2b of the water circulation pipe 2 constitutes the packer expansion channel in the present invention. As the fluid for inflating the packer 3, for example, water, air, or the like is used, but even a fluid such as cement milk that solidifies inside the packer 3 after the packer 3 is inflated. Good. Reference numeral 6 is a check valve provided in the opening 2b to prevent the fluid that has entered the inside of the packer 3 and expanded the packer 3 from flowing back to the hose 5.

Reference numeral 7 denotes a plurality of water passages formed on the outer peripheral surface 2a of the water circulation pipe 2 between the packers 3 and divided into multiple stages by the packer 3. Water is introduced into the contaminated ground G through the water passages 7. Or inhale the water in the contaminated ground G. One end of a plurality of independent hoses 8 is connected to each of the plurality of water passages 7, and the other ends of the plurality of hoses 8 are connected to a pressure supply source 1 and a pollution treatment device 9 installed on the ground. There is. In this embodiment, the pressure supply source 1 and the pollution treatment device 9 are integrated, and the pressure supply source 1 supplies pressure to the pollution treatment device 9. Multiple hoses 8
Constitutes the water circulation channel in the present invention. Injection well IW
In the above, each hose 8 and the water supply port 7 supply the pressure necessary for injecting water from the water supply port 7 into each ground G divided into multiple stages by the packer 3 from the pressure supply source 1.
Sourced from. In the present embodiment, the pressure of the pressure supply source 1 causes the water sent from the pollution control device 9 to be injected into the ground G from each water passage 7 through each hose 8 at a low pressure. Thus, the pressure source 1
As a result, water is injected at low pressure from each water passage 7, so that the injected water gradually permeates the entire ground G from the space portion X around the water passage 7. On the other hand, in the pumping well DW, the hose 8 and the water passage 7 are the same as the water passage 7
Is supplied from the pressure supply source 1 with the pressure required to suck the water in the ground G divided into multiple stages. In the present embodiment, the water supplied from the pressure supply source 1 causes the water in each ground G to be naturally sucked from the water passage 7 to the inside of the hose 8. In addition, the natural suction means that the air pressure inside the water passage 7 and the hose 8 is made lower than the air pressure inside the ground G outside the water passage 7, and the water in the ground G is contaminated from the water passage 7 due to this pressure difference. It is to move naturally to the processing device 9. Here, a predetermined vacuum pressure is applied to the inside of the water passage 7 and the hose 8 to suck the water in the ground G from the water passage 7. In this way, the water in each ground G is naturally sucked from each water passage 7 by the pressure supply source 1, so that the water that has permeated the entire ground G is surrounded by the space X around the water passage 7. And then naturally moves from the water passage 7 through the hose 8 to the pollution treatment device 9.

By the low-pressure injection of water into the ground G in the water injection well IW and the natural suction of the water in the ground G in the pumping well DW, each ground G is divided into multiple stages.
It is possible to circulate water evenly to every corner of the ground and to purify every corner of the ground G. Further, although the atmospheric pressure in the ground G changes depending on the depth of the ground G where the water passage 7 is arranged, the water supply port 7 and the hose 8 are connected depending on the depth of the ground G where the water supply port 7 is arranged by the pressure supply source 1. It is possible to uniformly inject or suck water from all the water passage ports 7 by supplying pressure to and adjusting the pressure inside these.

The pollution treatment device 9 installed on the ground is composed of a heavy metal ion treatment device, an organic matter / microorganisms treatment device, a wastewater treatment device, a water replenishment device, etc., and a water inlet 7 to a hose 8 in the pumping well DW. The contaminated water in the contaminated ground G that has been sucked in through is passed through each of the above devices to be purified. Then, the water purified by the pollution control device 9 is injected into the ground G through the water inlet 7 of the water injection well IW through the hose 8. The water purified by the pollution treatment device 9 is harmless because it promotes the separation of the microorganisms that decompose the harmful substances, the nutrients that activate the microorganisms, and the harmful substances from the ground G, or causes a chemical reaction with the harmful substances. It contains chemicals that turn into chemicals.

Reference numeral 11 is a plurality of filters installed so as to cover the outer peripheral surface 2a of the water circulation pipe 2 between the packers 3, and as shown in FIG.
1b and. A metal material such as iron or stainless steel is used as the material of the filter 11 and prevents sand, gravel, etc. contained in the water in the ground G from entering the hose 8 through the water passage 7. Therefore, it is possible to constantly and stably inject and suck water from the water inlet 7 of the water injection well IW or the pumping well DW. In addition, the spacer 11 of the filter 11
a is in contact with the outer peripheral surface 2a of the water circulation pipe 2 and the filter 1
1 and the outer peripheral surface 2a of the water circulation pipe 2 form a gap Y (FIG. 1). Therefore, in the water injection well IW, the water injected from the water inlet 7 is first filled in the gap Y, and oozes into the space X between the packers 3 from the gap Y through the entire surface of the filter 11 and from there. Since it penetrates into each ground G divided into multiple stages by the packer 3,
Water can be permeated to the entire ground G in all directions of the water injection well IW. On the other hand, in the pumping well DW, the water in the ground G first gathers in the space portion X between the packers 3 and soaks into the gap Y from the space portion X through the entire surface of the filter 11, and the soaked water is Since it is sucked from the water passage 7 to the inside of the hose 8, water can be sucked from the entire ground G in all directions of the pumping well DW. As a result, the water circulation pipe 2
While the number of water passages 7 formed on the outer peripheral surface 2a is minimized, water can be circulated in each of the grounds G divided in multiple stages, and the contaminated ground G can be efficiently purified.

Next, the steps of the method for cleaning the contaminated ground G, which is carried out by using the above-mentioned water circulating apparatus 100, will be described. Figure 4
~ Fig. 6 is a diagram for explaining the method for purifying contaminated ground according to the present invention, Fig. 4 shows an installation process for installing the water circulation device 100 in the water injection well IW, and Fig. 5 is a pumping well DW and water injection well IW.
The purification process of purifying the contaminated ground G by circulating water is shown. FIG. 6 shows a plan view of FIG.

In FIG. 4, the case of inserting the water circulation pipe 2 constituting the water circulation device 100 into the water injection well IW will be described as an example, but the water circulation pipe 2 is inserted into the pumping well DW (shown in FIG. 5). Also in the case, the following description is the same. In addition, here, the pressure supply source 1 that constitutes the water circulation device 100.
The fluid supply source 10 for supplying the fluid for expanding the packer 3 and the pollution treatment device 9 for purifying the water in the ground G are not shown (all shown in FIG. 5). Figure 4 (a)
The state where the water circulation pipe 2 is inserted in the water injection well IW provided in the contaminated ground G is shown. First, the contaminated ground G is excavated to a predetermined depth by a boring machine or the like (not shown) using the casing pipe 12 to provide a water injection well IW. Next, as shown in FIG. 4A, the casing pipe 1
Insert the water circulation pipe 2 into 2. When the water circulation pipe 2 is inserted into the casing pipe 12 as shown in FIG. 4B, only the casing pipe 12 is pulled out from the water injection well IW, and the water circulation pipe 2 (shown in cross section is shown in FIG. 4C). ) Is exposed inside the water injection well IW. And
The fluid is simultaneously sent from the fluid supply source 10 (FIG. 5) installed on the ground through the hose 5 into the plurality of packers 3, and the plurality of packers 3 are expanded as shown in FIG. 4 (d). The plurality of expanded packers 3 are in close contact with the inner surface of the water injection well IW to form the space X between the packers 3, and
The contaminated ground G is divided into multiple stages in the depth direction. With the above steps, the installation of the water circulation device 100 in the water injection well IW is completed.

As described above, the water circulation device 1 is installed in the water injection well IW.
No. 00 is installed at the same time, as shown in FIG. 5, the water circulation device 100 is also installed in the pumping well DW in the same process as in FIG. It should be noted that a plurality of pumping wells DW are provided so as to surround a plurality of water injection wells IW provided in the contaminated ground G as shown in FIG. 6, and in the present embodiment, a plurality of water injection wells IW and pumping wells DW are provided. Are arranged in a staggered pattern. The parts surrounded by broken lines are the injection well IW and the pumping well DW shown in FIG. By arranging a plurality of water injection wells IW and pumping wells DW in the contaminated ground G in this way, water can be circulated in the ground G over a wide area. Moreover, since a wide range of cleaning work can be performed at one time, the period for cleaning the contaminated ground G can be shortened.

In FIG. 5, a pollution treatment device 9 is installed on the ground side by side with the pressure supply source 1 and the fluid supply source 10. When the water purified by the pollution treatment device 9 is sent by the pressure supply source 1 through the plurality of independent hoses 8 to the water circulation pipe 2 inserted in the water injection well IW, the purified water is supplied to each of the plurality of water passages 7. Is injected at low pressure into the ground G.
The water injected at a low pressure is filled in the gap Y between the filter 11 and the outer peripheral surface 2a of the water circulation pipe 2, and passes through the entire surface of the filter 11 through the gap Y to form each space X formed by the expansion of the packer 3. After bleeding out to fill the space X, the packer 3 penetrates into the ground G divided into multiple stages in the depth direction. At this time, water permeates horizontally into the ground G in all directions of the water injection well IW.

When water permeates into each of the ground G divided into multiple stages, the contaminated water contained in the ground G from the beginning permeates to the pumping well DW side, and the pumping well DW.
Infiltrates into each space X of the. When the space X is filled with polluted water, it penetrates through the entire surface of the filter 11 into the gap Y between the filter 11 and the outer peripheral surface 2a of the water circulation pipe 2, and soaks into the gap Y. Water is naturally sucked from each water passage 7 by the pressure supply source 1 and sent to the pollution treatment device 9 through the hose 8.

After this, the water sent to the pollution treatment device 9 is
It is purified by each device of the pollution treatment device 9 and again sent to the water circulation pipe 2 of the water injection well IW by the pressure supply source 1.
Then, the water is injected from each of the plurality of water passages 7 at a low pressure, exudes from the gap Y through the entire surface of the filter 11 into the space portion X, and permeates into each ground G divided into multiple stages. As a result, the water that had previously permeated into the ground G released microorganisms into the ground G, and permeated to the pumping well DW side while separating the harmful substances from the ground G and taking them in, and then again pumping well DW. Go into each space X of. Then, the water soaks into the gap Y from the space portion X through the entire surface of the filter 11, and the water that has soaked into the gap Y is naturally sucked from the water supply ports 7 by the pressure supply source 1 and then contaminated through the hose 8. It is sent to the processing device 9. After that, the water sent to the pollution treatment device 9 as described above is purified by each device of the pollution treatment device 9, and is again sent to the water circulation pipe 2 of the water injection well IW by the pressure supply source 1 from the water inlet 7. Injected. In this way, by continuously circulating the water independently for each ground G divided into multiple stages in the depth direction, harmful substances contained in each contaminated ground G are gradually decomposed by microorganisms, and chemicals etc. As a result, the entire contaminated ground G is purified. In addition, at this time, by checking the degree of contamination of water that is sucked from each water inlet 7 of the pumping well DW and passes through the hose 8,
It is possible to confirm the degree of purification of the ground G for each contaminated ground G divided into multiple stages, and circulate the water in the ground G while adjusting the injection amount and suction amount of water based on the confirmed results. The contaminated ground G can be purified.

By doing the above, the packer 3
Each ground G divided into multiple stages in the depth direction by
Since the water purified by the pollution treatment device 9 is circulated by an independent route for each of them, the water level in the ground G does not decrease around the pumping well DW, and the pumping well IW to the pumping well DW do not decrease.
The water can be circulated uniformly in the contaminated ground G while maintaining the same level of water level L (shown in FIG. 5) over the entire period, and the entire contaminated ground G can be purified. In addition, since purified water is injected from the water inlet 7 of the water injection well IW and water in each ground G is sucked from the water inlet 7 of the pumping well DW for each of the ground G divided into multiple stages, The permeation speed of water that permeates into the ground G becomes faster, and the water can be circulated quickly in the ground G to shorten the period for cleaning the contaminated ground G. Further, when the packer 3 is expanded by providing the packer 3 at a predetermined interval on the outer peripheral surface 2a of the water circulation pipe 2 based on the distribution state of the stratum in the depth direction of the contaminated ground G, when the packer 3 is expanded,
The contaminated ground G can be divided into multiple stages according to the distribution of the stratum. Therefore, by circulating water in each ground G, water can be uniformly circulated in the entire contaminated ground G regardless of the distribution state of the stratum in the contaminated ground G, and purification can be performed. .

In the above-described embodiment, the case where a plurality of water injection wells IW and pumping wells DW in which the water circulation device 100 is installed are arranged in a staggered manner in the contaminated ground G is taken as an example. The present invention is not limited to this. In addition to this, a plurality of water injection wells IW and pumping wells DW may be arranged in parallel as shown in FIG. 7 (a), or a plurality of water injection wells IW may be arranged as shown in FIG. 7 (b). The water injection well IW and the pumping well DW may be arranged in a grid pattern. Further, the plurality of water injection wells IW and the pumping wells DW may not be regularly arranged in the vertical and horizontal directions, and for example, the plurality of water intake wells DW may be radially arranged around the plurality of water injection wells IW. In other words, there are multiple injection wells I in the contaminated ground G.
W is provided, a plurality of pumping wells DW are provided so as to surround these water injection wells IW, and the water circulating device 100 is installed in each of the water supply wells IW, so that the water injected from the plurality of water injection wells IW is distributed around the water injection well IW. Any arrangement may be used as long as it can be circulated in the ground G. By doing this, the contaminated ground G can be purified over a wide range, and
Since it is possible to perform a wide range of purification work at one time, it is possible to shorten the construction period.

Further, in the above embodiment, the water circulation pipe 2 inserted in the water injection well IW performs an injection step of injecting purified water into the ground G from the water inlet 7 to circulate the water circulation inserted in the pumped well DW. The pipe 2 is described as an example in which the suction process of sucking the water in the ground G from the water inlet 7 is performed, but the water circulation pipe 2 inserted in each of the water injection well IW and the pumping well DW performs the injection process. The suction process may be alternately switched. In addition, this process is switched by switching the pressure supplied by the pressure supply source 1 through which the hoses 8 of the water circulation pipes 2 of the water injection well IW and the pumping well DW communicate with each other, and a purification circuit for purifying the water of the pollution treatment device 9. It is done by switching. Further, the switching timing may be switched at a predetermined time interval or may be switched according to the degree to which the ground G is cleaned. By doing so, the permeation directions of the water that permeates the respective ground G divided into multiple stages by the packer 3 are the direction from the injection well IW to the pumping well DW and the direction from the pumping well DW to the injection well IW. The water can be circulated evenly in the ground G around the water injection well IW and the pumping well DW, and the contaminated ground G can be purified. In addition, when water is sucked from the water passage 7 through the filter 11 for a long period of time, the filter 11 may be clogged with sand or gravel in the ground G. Since sand and gravel clogging the filter 11 in the process is removed from the filter 11 in the injection process, water can be circulated in the ground G for a long period of time, and the contaminated ground G can be purified.

Further, in the above embodiment, the water circulation pipe 2
The case where the fluid is supplied to the plurality of packers 3 provided in the packer 3 through the single hose 5 that constitutes the packer expansion channel to simultaneously expand the plurality of packers 3 is given as an example, but the present invention is not limited to this. Instead, each packer 3 may be provided with a plurality of independent hoses so that fluid can be supplied individually to each packer 3, and each packer 3 may be inflated one by one. By doing so, only the packers 3 necessary for the depth of the pumping well DW and the injection well IW and the distribution of strata in the contaminated ground G are individually expanded, and the contaminated ground G is divided into multiple stages in the depth direction. You can

Further, in the above embodiment, the contaminated ground G is divided into multiple stages in the depth direction by expanding the plurality of packers 3, and water is circulated in each of the divided ground G in the same manner to form the ground G. Although the case of purifying the whole is given as an example, the present invention is not limited to this, and in addition to this, water is intensively circulated in a part of the ground G among the ground G divided into multiple stages. You may make it purify. By doing this, water is intensively circulated and purified in the portion of the ground G where the degree of pollution is significant, and the amount of water that is circulated is suppressed in other portions where the degree of pollution is not significant. By purifying, the cost of the purification method can be reduced as a whole.

Further, in the above embodiment, the water circulation pipe 2 for the water injection well IW and the water circulation pipe for the pumping well DW are both shown as examples in which the water circulation pipe 2 of FIG. 1 is used, but both have the same structure. It does not have to be a pipe. For example, the water circulation pipe for the pumping well DW shown in FIG. 1 may be used, and the water circulation pipe 2 for the water injection well IW may have a structure without the filter 11. Further, as the water circulation pipe, for example, JP 2000-8
It is also possible to divert a multi-packer for injecting a chemical solution, which is used in the ground improvement method, as described in JP-A No. 0640 and JP-A No. 2000-273859.

[0043]

According to the present invention, since purified water is circulated through an independent path for each ground divided by the packer in multiple stages in the depth direction, the water is uniformly circulated in the contaminated ground. Therefore, it is possible to purify the entire contaminated ground.

[Brief description of drawings]

FIG. 1 is a side view showing a water circulation device according to the present invention.

FIG. 2 is a side view showing a water circulation device according to the present invention.

FIG. 3 is a perspective view showing a filter provided in the water circulation device according to the present invention.

FIG. 4 is a side view for explaining a method for cleaning contaminated ground according to the present invention.

FIG. 5 is a side view illustrating a method for cleaning contaminated ground according to the present invention.

FIG. 6 is a plan view illustrating a method for purifying contaminated ground according to the present invention.

FIG. 7 is another plan view for explaining the method for cleaning the contaminated ground according to the present invention.

FIG. 8 is a cross-sectional view showing a conventional purification device for contaminated ground.

FIG. 9 is a plan view showing a conventional device for purifying contaminated ground.

[Explanation of symbols]

1 Pressure supply source 2 water circulation pipe 2a opening 3 packers 5 hoses 7 water passage 8 hose 9 Pollution treatment equipment 11 filters 11a spacer 100 water circulation device G contaminated ground DW pumping well IW injection well

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuaki Haraguchi             2-16-7 Oimazatominami, Higashisei-ku, Osaka-shi, Osaka             issue (72) Inventor Akira Kamide             1-13-8 Hishiyahigashi, Higashi-Osaka City, Osaka Prefecture F-term (reference) 2D043 DA04 EB06                 4D004 AA41 AB03 AB06 AC07 CA13                       CA18 CA40 CB50 CC06                 4D064 AA40 BH02 BH05 BK01

Claims (8)

[Claims] 1. A pumping well and a water injection well are provided in the contaminated ground, water in the contaminated ground is pumped from the pumping well and purified through a pollution treatment device installed on the ground, and purified by this pollution treatment device. By injecting water into the ground from the water injection well and returning it, in the purification method of the contaminated ground for circulating the water in the contaminated ground to purify the contaminated ground, in the depth direction of the pumping well and the water injection well. A plurality of inflatable packers provided at a predetermined interval, and a plurality of water passages formed between the packers for injecting or sucking water into the contaminated ground, and a water circulation device, Inserted into the water injection well and the pumping well, respectively, by expanding the packer, divide the contaminated ground into multiple stages in the depth direction, and from the water passage of the water circulation device inserted into the water injection well into the ground. While injecting water purified by the pollution treatment device, by suctioning water in the ground from the water passage of the water circulation device inserted in the pumping well and sending it to the pollution treatment device, the water is separated into the multi-stages. A method for purifying contaminated ground, characterized in that the contaminated ground is purified by circulating water through an independent path for each ground. 2. The method for purifying contaminated ground according to claim 1, wherein the water purified by the pollution control device is injected into the ground through a filter from the water passage port of the water circulation device inserted in the water injection well. At the same time, a method for purifying contaminated ground is characterized in that water in the ground is sucked through a filter from the water passage of the water circulation device inserted in the pumping well. 3. The method for purifying contaminated ground according to claim 1 or 2, wherein the water purified by the pollution treatment device is injected into the ground from the water passage of the water circulating device inserted into the water injection well to a low pressure. The method for purifying contaminated ground is characterized in that the water in the ground is naturally sucked from the water passage of the water circulation device inserted into the pumping well. 4. The method for cleaning contaminated ground according to claim 1, wherein a plurality of the water injection wells are provided in the contaminated ground, and a plurality of water injection wells are provided so as to surround each of the plurality of water injection wells. Establishing the pumping well,
A method for purifying contaminated ground, characterized in that the water circulating device is inserted into each of the water injection well and the pumping well. 5. The method for purifying contaminated ground according to any one of claims 1 to 4, further comprising: an injection step of injecting the water purified by the pollution control device into the ground through the water passage opening; A method for purifying contaminated ground, characterized by alternately performing a suction step of sucking water in the ground from a water outlet by the water circulating device inserted in the water injection well and the water pumping well. 6. A water injection well and a pumping well provided in the contaminated ground, each of which is used to inject water purified by a pollution control device into the contaminated ground, and in the pumped well, in the contaminated ground. It is a water circulation device that circulates water in the contaminated ground by sucking the water of the above and sending it to the pollution treatment device. It is provided at predetermined intervals on the outer peripheral surface and expands the contaminated ground in multiple stages in the depth direction. A plurality of inflatable packers that are divided into two parts, and water that is formed on the outer peripheral surface between the packers and that is purified by the pollution treatment device is injected into the contaminated soil or the water in the contaminated soil is sucked into the pollution treatment device. A plurality of water passages for sending to, a packer expansion flow passage that is a flow passage of a fluid for inflating the plurality of packers, and a plurality of water passages and the pollution treatment device communicate with each other, the plurality of Inject from the water outlet Alternatively, a plurality of independent water circulation flow paths that are water flow paths for sucking water are provided. 7. The water circulation apparatus according to claim 6, wherein a plurality of filters are provided to cover the outer peripheral surface between the packers, and the filter is provided with a spacer between the outer peripheral surface and the filter. Water circulation device. 8. The water circulation device according to claim 6 or 7, further comprising a pressure supply source for supplying a pressure necessary for injecting water from the water passage or sucking water from the water passage. A water circulation device characterized by the above.