JP4375592B2 - Soil and groundwater purification methods - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a soil and groundwater purification method for purifying soil and groundwater.
[0002]
[Prior art]
As purification methods for purifying contaminated soil and / or contaminated groundwater, there are roughly divided into a physicochemical treatment method and a biological purification treatment method. In the physicochemical treatment method, the excavated soil is incinerated. There are an incineration treatment method to purify, a thermal desorption method to purify the excavated soil by low-temperature heat treatment with a rotary kiln, a cleaning method to wash and purify the excavated soil, and the biological purification treatment method includes excavation The soil is made high, the air is supplied to the high plateau to activate microorganisms in the soil, and the microbetting method (bioventing method) that purifies by the action of these microorganisms, air is supplied to the ground. There are in-situ methods (for example, air purging method) that activate microorganisms in the soil and purify them by the action of these microorganisms. With this in-situ method, it is possible to purify contaminated soil and / or contaminated groundwater without excavation, and it is possible to reduce the cost of purification treatment because it does not require excavation costs. I'm bathing.
[0003]
[Problems to be solved by the invention]
In this in-situ method, when injecting air into the ground, it is difficult to uniformly inject the air into the area to be purified as required, so that the oxygen supply to the area to be purified is insufficient. One of the reasons is that the purification ability is low.
An object of the present invention is to provide a method for purifying soil and groundwater that can uniformly inject or infiltrate air into a region to be purified in the ground and improve the supply of air to the region to be purified. .
[0004]
Another object of the present invention is to provide a soil and groundwater purification method capable of improving the purification capacity.
[0005]
  The present inventionAn air supply pipe for supplying air is disposed inside the liquid supply pipe for supplying liquid and is embedded in the ground, and the air supply pipe is supplied to the liquid flowing through the liquid supply pipe at the tip of the liquid supply pipe. Mixing the air flowing through, and by mixing such liquid and air,A liquid containing fine bubbles having a size of 1 to 10000 μm is injected or penetrated into the ground, and the rising speed of the fine bubbles contained in the liquid is slowed down and diffused laterally to supply oxygen into the ground. It is characterized in that the soil is decomposed and purified by activating the growth or activity of microorganisms that decompose the pollutants contained in the ground.
  According to the present invention, a liquid containing fine bubbles having a size of 1 to 10,000 μm is injected or infiltrated into the ground. Such fine bubbles have a slow ascending rate in the ground, and bubbles contained in the injected or infiltrated liquid diffuse laterally, thereby providing oxygen supply into the ground (groundwater and / or underground soil). Uniformity is promoted. When oxygen supply is made uniform in this way, the growth or activity of microorganisms in the ground is activated, the purification action by microorganisms is enhanced, and the contaminated soil and / or contaminated groundwater is efficiently purified using microorganisms. Can do.
  Also, since the air supply pipe is arranged inside the liquid supply pipe in the radial direction and the air from the air supply pipe is mixed with the liquid from the liquid supply pipe at the tip of the liquid supply pipe, the liquid immediately before being injected into the soil The gas is mixed with the liquid to produce a liquid containing fine bubbles, which can be injected or penetrated into the ground in the form of fine bubbles. In addition, since the air supply pipe has a double structure in which the air supply pipe is radially inward in this way, the liquid supply pipe and the air supply pipe can be embedded in the ground relatively easily.
[0006]
  In the present invention, the liquid containing fine bubbles is dispersed substantially uniformly in the area to be purified in the ground.
  According to the present invention, the fineAir bubbles, 1 to 10000 μmBubbles of a large size are slow in the ground and diffuse in the lateral direction, so that the liquid containing fine bubbles is dispersed substantially uniformly in the region to be purified, and thus dispersed in the region. The growth or activity of the existing microorganisms is activated and can be purified substantially uniformly over the entire area to be cleaned.
[0007]
  The present invention also provides:An air supply pipe for supplying air is disposed inside the liquid supply pipe for supplying liquid and is embedded in the ground, and the air supply pipe is supplied to the liquid flowing through the liquid supply pipe at the tip of the liquid supply pipe. Mixing the air flowing through, and by mixing such liquid and air,A region to be purified in the ground by injecting or penetrating a liquid containing fine bubbles having a size of 1 to 10,000 μm into the ground, slowing the rising speed of the fine bubbles contained in the liquid, and diffusing in the lateral direction The liquid is allowed to flow through, and the liquid flow cleans and purifies the contaminants contained in the soil and / or adhering to the soil surface.AccordingIt is characterized by infiltrating oxygen between narrow soil particles.
  According to the present invention, a liquid containing fine bubbles having a size of 1 to 10,000 μm is injected or infiltrated into the ground. Such fine bubbles have a low rising speed in the ground, and the liquid containing the fine bubbles flows through the region to be purified. Accordingly, the region to be purified, that is, the contaminant contained in the soil and / or the contaminant attached to the soil surface is cleaned by the flow of the liquid and the flow of the fine bubbles contained therein. These fine bubbles, for example, bubbles having a size of 1 to 1000 μm, are sufficiently small in size and can enter between narrow soil particles by the flow of the liquid, thereby enhancing the purification ability.
  Further, since the air supply pipe is arranged inside the liquid supply pipe in the radial direction and the liquid from the liquid supply pipe is mixed with the liquid from the liquid supply pipe at the tip of the liquid supply pipe, the fineness is the same as described above. It can be injected or penetrated into the ground in the form of bubbles, and the liquid supply pipe and the air supply pipe can be embedded in the ground relatively easily.
[0008]
Further, in the present invention, groundwater is used as a liquid containing fine bubbles, a pumping hole is provided in relation to an area to be purified, and after the fine water is included in the groundwater pumped from the pumping hole, It is characterized by injecting or seeping into the ground and circulating groundwater through the area to be purified.
According to the present invention, a pumping hole is dug in relation to a region for purifying soil, and groundwater in the ground is pumped from the pumping hole. As the liquid that is injected or penetrates into the ground, groundwater from the pumping hole is used, and fine bubbles are contained in the groundwater and injected or penetrated into the ground. If it does in this way, groundwater will be circulated through the area | region which should be purified, and the area | region which should be purified using groundwater, ie, contaminated soil and / or contaminated groundwater, can be purified as needed.
[0009]
Moreover, in this invention, after adding the nutrient of a decomposition microorganism to the groundwater pumped up from the pumping hole, it inject | pours or infiltrates in the ground.
According to the present invention, since nutrients of decomposing microorganisms are added to groundwater, groundwater containing nutrients is injected or infiltrated into the ground. Therefore, a nutrient substance is given to the microorganisms in the soil, the proliferation or activity of the microorganisms is further activated, and the purification action by the microorganisms can be further enhanced.
[0010]
In the present invention, a decompression pump is used to decompress the pumping hole, and groundwater is pumped in a decompressed state by the decompression pump, and the pumped groundwater is injected or infiltrated into the ground.
According to the present invention, a decompression pump is used when pumping groundwater from the pumping hole, and the inside of the pumping hole is maintained in a decompressed state by the decompression pump. A large amount of groundwater can be pumped by pumping up under reduced pressure by a vacuum pump.
[0011]
Further, in the present invention, groundwater pumped up from the pumping hole is caused to flow through a heavy metal treatment device and an oil content removal device, heavy metal contained in the groundwater is removed by the heavy metal treatment device, and oil content contained in the groundwater is removed by the oil content removal device. It is characterized by including air in the groundwater from which heavy metals and oil have been removed.
According to the present invention, the pumped-up groundwater is processed by the heavy metal processing device and the oil removing device. The heavy metal removal device removes heavy metals in the groundwater, and the oil removal device removes oil components in the groundwater. By injecting or infiltrating the groundwater thus purified into the ground, the area to be purified is more effective. Can be purified.
[0014]
Furthermore, the present invention is characterized in that a fine bubble generating member having a large number of fine holes is provided at the tip of a pipe for injecting a liquid containing fine bubbles into the ground.
According to the present invention, since the fine bubble generating member is provided at the tip of the pipe for injecting the liquid, when the liquid containing the bubbles is injected through the fine bubble generating member, the bubbles are further miniaturized and smaller. Liquid can be injected into the ground in the form of bubbles.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of a method for purifying soil and groundwater according to the present invention will be described with reference to the accompanying drawings.
First embodiment
First, with reference to FIG.1 and FIG.2, the 1st Example of the purification method of the soil and groundwater according to this invention is described. FIG. 1 is a plan view schematically showing a first embodiment of a soil and groundwater purification system to which the first embodiment of the soil and groundwater purification method according to the present invention is applied, and FIG. It is sectional drawing which shows simply the purification system of soil and groundwater.
[0016]
1 and 2, the soil and groundwater purification system according to the first embodiment includes an air injection mechanism 6, and in this embodiment, one side is located at a predetermined portion of a region 8 to be purified by the air injection mechanism 6. It is provided at the four corners of a square area 8 of about 20 m. The air injection mechanism 6 injects a liquid containing fine bubbles, in this embodiment, water containing fine air into the ground as described later. The air injection mechanism 6 can be appropriately provided in consideration of the purification capability and the like.
[0017]
The illustrated air injection mechanism 6 includes a main liquid supply pipe 1 that supplies a liquid such as water, and first and second branch liquid supply pipes 2 and 4 that extend from the main liquid supply pipe 1. Most of these branch liquid supply pipes 2 and 4 are embedded in the ground. In this embodiment, the first branch liquid supply pipe 2 is formed shorter than the second branch liquid supply pipe 4. As shown in FIG. 2, the surface portion has an unsaturated layer R having voids between soil particles on the surface thereof, and a saturated layer S in which the soil particles are occupied by groundwater below the unsaturated layer R. Exists. For example, when the soil of the saturated layer S is contaminated, the first branch liquid supply pipe 2 is buried so as to extend downward in the ground to a relatively shallow portion of the saturated layer S, and the second branch liquid supply pipe 4. Is embedded in the ground so as to extend downward into a relatively deep portion of the saturated layer. The embedment length L1 of the first liquid supply pipe 2 is set to about 3000 mm, for example, and by setting in this way, the liquid (described later) from the first liquid supply pipe 2 flows into the saturated layer S from the tip inlet. It is injected into a relatively shallow part. Further, the embedded length L2 of the second air supply pipe 4 is set to about 7000 mm, for example, and the liquid from the second air supply pipe 4 is relatively deep in the saturated layer S from the tip inlet thereof. Injected into. The main liquid supply pipes 1 of the four air injection mechanisms 6 are connected via a connection pipe (not shown), and are connected to a liquid supply source (not shown) such as a liquid supply pump via the connection pipe. .
[0018]
First and second air supply pipes 5 and 7 for supplying air as a gas are connected to the first and second branch liquid supply pipes 2 and 4 of each air injection mechanism 6, and these first and second air are supplied. Supply pipes 5 and 7 are connected to an air supply source (not shown) such as an air compressor. Air from the first air supply pipe 5 is supplied to the first branch liquid supply pipe 2, and the liquid containing fine bubbles formed by mixing the air with the liquid is saturated through the first branch liquid supply pipe 2. Implanted into a relatively shallow portion of layer S. The air from the second air supply pipe 7 is supplied to the second branch liquid supply pipe 4, and the liquid containing fine bubbles is injected into a relatively deep portion of the saturated layer S through the second branch liquid supply pipe 4. Is done.
[0019]
As the liquid to be injected, water such as rivers and ponds, ground water, tap water, and the like can be used, and the size (diameter) of bubbles included in this is 1 to 10,000 μm. When the size of the bubbles exceeds 10,000 μm, the rising speed of the bubbles in the saturated layer S increases in the ground and in this form, and the amount of air staying in the saturated layer S decreases. Therefore, the supply of air into the ground cannot be made uniform, and the degree of improvement of the purification action described later is reduced. It is more effective that the size of bubbles contained in the liquid is small, for example, it is desirable to be 1 to 1000 μm, and when such a size, the bubbles enter between narrow soil particles. . In addition, the liquid containing a fine bubble can use the premix nozzle known per se which mixes air in a liquid and produces | generates the liquid which has a bubble, for example.
[0020]
The ground surface 12 of the region 8 to be purified of the ground is covered with, for example, a sheet 10 so that the air injected into the saturated layer S rises and is not diffused from the surface 12 into the atmosphere. When the saturated layer S is polluted, if the pollutant is a volatile organic compound (VOCs) such as BTX, the pollutant may be released into the atmosphere due to the rise of the injected air. It is.
A suction tube 14 is provided in combination with the sheet 10. The suction tube 14 is constituted by a hollow tube member, and a plurality of suction holes (not shown) are provided at intervals in the axial direction thereof. In this embodiment, the suction pipe 14 is arranged in a rectangular shape on the outer periphery of the region 8 to be processed, and a suction pipe 16 is connected to a part of the suction pipe 16 via the suction machine 18 and the connection pipe 20. It is connected to an adsorption tower (not shown). The adsorption tower is composed of, for example, a known activated carbon adsorption tower. As shown in FIG. 2, the suction pipe 14 is buried near the ground surface of the unsaturated layer R. Accordingly, the air rising from the saturated layer S through the unsaturated layer R is sucked from the suction hole of the suction pipe 14 by the suction action of the suction machine 18, and is shown by the arrow 22 through the suction pipe 14, the suction pipe 16 and the connection pipe 20. Is sent to an adsorption tower (not shown), and pollutants such as VOCs are completely removed in the adsorption tower and then diffused into the atmosphere.
[0021]
In this purification system, a liquid such as water is supplied to the main liquid supply pipe 1 of each air injection mechanism 6 via a connecting pipe (not shown), and the first and second branch liquids are supplied from the main liquid supply pipe 1. The feed pipes 2 and 4 are fed. Air is supplied to the first branch liquid supply pipe 2 through the first air supply pipe 5 and is supplied to the second branch liquid supply pipe 4 through the second air supply pipe 7. Since the liquid and air are supplied in this way, the liquid mixed with air in the first branch liquid supply pipe 2, that is, the liquid containing fine bubbles, flows from the injection port at the tip (lower end) of the saturated layer S. The liquid injected into the relatively shallow portion and mixed with the air in the second branch air supply pipe 4, that is, the liquid containing fine bubbles, is relatively in the saturation layer S from the inlet (lower end) thereof. It is injected into the deep part. Since the bubbles contained in the liquid are fine, the rising speed in the saturated layer is slow, and therefore the residence time in the saturated layer is long, which can promote the uniform air supply to the saturated layer. . As a result, the infused air activates the endogenous bacteria in the soil of the saturated layer S, that is, the growth or activity of decomposing microorganisms that decompose the pollutants, and uses the functions of the endogenous bacteria in the soil and / or groundwater. It can decompose pollutants in the soil and promote the purification of soil and groundwater. In addition, fine bubbles easily penetrate into the saturated layer, penetrate between narrow soil particles, promote air permeation into the saturated layer, and further diffuse into the saturated layer due to lateral diffusion. The region 8 to be cleaned can be cleaned substantially uniformly. Furthermore, the soil and / or groundwater is also cleaned by the liquid injected into the saturated layer S and the flow of bubbles contained therein.
[0022]
Second embodiment
Next, a second embodiment of the soil and groundwater purification method according to the present invention will be described with reference to FIG. FIG. 3 is a sectional view schematically showing a part of the second embodiment of the soil and groundwater purification system to which the second embodiment of the soil and groundwater purification method according to the present invention is applied. In FIG. 2, the suction tube and the sheet are omitted. In the following description, substantially the same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.
[0023]
In FIG. 3, in the system of the second embodiment, a pumping well 32 as a pumping hole is dug in relation to the region to be purified (see FIG. 2), and the pumping well 32 is a relatively deep part of the saturated layer. Until drilled. One or more pumping wells 32 are provided in the region to be purified and / or adjacent to the region to be purified, for example, in the center of the four air injection mechanisms 6 in the embodiment shown in FIG. be able to.
In the second embodiment, the groundwater accumulated in the pumping well 32 is used as a liquid containing fine bubbles. A suction pipe 48 extends into the ground water 46 accumulated in the pumping well 32. The suction pipe 48 is connected to a suction pump 50, and a liquid supply pipe 52 connected to the suction pump 50 is formed in a saturated layer below the ground. It extends to a relatively deep part. The air supply pipe 54 extends downward in the ground substantially parallel to the liquid supply pipe 52, and the tip (lower end) thereof is connected to the tip (lower end) of the liquid supply pipe 52. The other end of the air supply pipe 54 is connected to, for example, an air compressor (not shown), and air from the air compressor is supplied to the tip of the liquid supply pipe 54. Other configurations of the second embodiment are substantially the same as those of the first embodiment described above.
[0024]
In the second embodiment, the ground water 46 accumulated in the pumping well 32 is pumped up by the suction action of the suction pump 50, and the ground water 46 thus pumped is supplied to the liquid supply pipe 52 through the suction pipe 48. Air is supplied from an air compressor (not shown), and this air is supplied to the tip of the liquid supply pipe 54 through the air supply pipe 54. At the tip of the liquid supply pipe 52, the air flowing through the air supply pipe 54 is mixed with the liquid flowing through the liquid supply pipe 52, and thus mixed to produce water containing fine bubbles, and the water containing bubbles is supplied to the liquid supply It is injected into the ground from the tip injection port of the pipe 52. Since water (groundwater) containing fine bubbles is injected into the saturated layer in the same manner as described above, air supply to the ground can be made uniform, and soil can be obtained as in the first embodiment. And / or groundwater can be purified.
[0025]
This second embodiment further has the following characteristics in relation to using the groundwater accumulated in the pumping well 32 as the liquid to be injected. That is, since the liquid to be injected is groundwater, it can be obtained easily and inexpensively, and the processing cost of the purification system can be reduced. In addition, since the groundwater in the saturated layer accumulates in the pumping well 32 and the accumulated groundwater is reinjected into the saturated layer with fine bubbles, the groundwater circulates through the area to be purified in the ground. It can be purified as required using circulating groundwater. In particular, as shown in FIG. 3, by circulating groundwater, water containing bubbles (groundwater) flows through the region to be purified, and this flow removes contaminants contained in the soil and / or attached to the soil surface. It can be washed away. In addition, the flow of groundwater allows fine bubbles to reach between the soil particles that cannot be reached by bubbles alone, thereby further promoting the purification of pollutants in the ground. In addition, in this second embodiment, since the mixing of groundwater and air is performed immediately before being injected into the saturated layer, the oxygen supply into the ground is more evenly promoted, and the soil and / or groundwater The purification action can be further enhanced.
[0026]
Third embodiment
Next, a third embodiment of the soil and groundwater purification method according to the present invention will be described with reference to FIG. FIG. 4 is a cross-sectional view schematically showing a part of the third embodiment of the soil and groundwater purification system to which the third embodiment of the soil and groundwater purification method according to the present invention is applied. In FIG. 2, the suction tube and the sheet are omitted.
In FIG. 4, in the purification system of the third embodiment, the inner diameter of the liquid supply pipe 82 embedded in the saturated layer is larger than the outer diameter of the air supply pipe 84 that supplies air, and the diameter of the liquid supply pipe 82. An air supply pipe 84 is disposed on the inner side in the direction, and the liquid supply pipe 82 and the air supply pipe 84 extend to the saturation layer. A connection pipe 86 connected to the suction pump 50 is connected to the base side (upper end side) of the liquid supply pipe 82, and the air supply pipe 84 is connected to an air compressor (not shown). Other configurations of the third embodiment are substantially the same as those of the second embodiment described above.
[0027]
In the third embodiment, the groundwater 46 in the pumping well 32 is pumped up by the suction action of the suction pump 50, and the groundwater thus pumped up is supplied through the connection pipe 86 and the liquid supply pipe 82, and the air compressor (FIG. Air from (not shown) is supplied through an air supply pipe 84. Immediately before being injected into the saturated layer in the ground, air from the air supply pipe 84 is jetted into the groundwater supplied through the liquid supply pipe 82, and these are mixed to produce water containing fine bubbles. The water containing bubbles is injected into the saturated layer from the inlet of the liquid supply pipe 82, and even if configured in this way, the same effect as the third embodiment is achieved.
[0028]
Fourth embodiment
Next, a fourth embodiment of the soil and groundwater purification method according to the present invention will be described with reference to FIG. FIG. 5: is sectional drawing which shows simply the principal part of 4th Embodiment of the soil and groundwater purification system to which the 4th Example of the purification method of the soil and groundwater according to this invention is applied.
In FIG. 5, in the purification system of the fourth embodiment, an oil removing device 92 for removing oil components contained in groundwater and a heavy metal treatment device for removing heavy metal components contained in groundwater. 94, and a supply pump 96 is disposed between them. A feed pipe 100 from the suction pump 50 is connected to the oil removing device 92, and the oil removing device 92 and the heavy metal processing device 94 are connected via a feed pipe 98, and a feed pump 96 is connected to the feed pipe 98. Is provided.
[0029]
In the fourth embodiment, the groundwater pumped from the pumping well 32 by the suction pump 50 is fed to the oil removing device 92 through the feed pipe 100. The oil removing device 92 removes the oil component contained in the groundwater, and the groundwater from which the oil component has been removed is fed to the heavy metal processing device 94 through the feed pipe 98 by the action of the supply pump 96. The heavy metal treatment device 94 removes heavy metal components contained in the groundwater, and the groundwater from which the oil components and heavy metal components have been removed passes through the feed pipe 104 by the feed pump 102, for example, in the second embodiment of FIG. It is fed to the liquid supply pipe 52 and then mixed with air and injected into the saturated layer as described above in a state containing fine bubbles.
[0030]
Thus, by using the groundwater from which the oil component and heavy metal component are removed as a liquid containing fine bubbles, the purification of the groundwater is remarkably promoted, whereby the saturation layer can be purified more efficiently. In particular, the groundwater pumped up from the pumping well 32 is circulated through the region to be purified, and purified groundwater is used for injection into the ground, so the soil and / or groundwater purification action is significantly improved.
In order to promote the purification action of the saturated layer, a purification or purification promoting substance may be added to the liquid (tap water, groundwater, etc.) injected into the saturated layer. Such a purification or purification promoting substance is a nutrient component for activating endogenous bacteria in soil or an adsorbent for adsorbing metal components in soil.
[0031]
In 2nd-4th embodiment, in order to enlarge the pumping capacity of the groundwater of the pumping well 32, it can comprise as shown, for example in FIG. That is, a casing pipe 132 is inserted into the pumping well 32, and a sand pool 134 is provided at the bottom (tip) of the casing pipe 132. The lower portion 136 of the casing tube 132 is formed to have a somewhat smaller outer diameter, and a slit tube 138 is provided so as to cover the periphery of the lower portion 136, and the slit tube 138 is spaced apart in the axial direction (vertical direction in FIG. 6). A number of slits 140 are provided. An inflow port 142 is provided at the bottom of the casing tube 132. A pumping pump 144 is provided in the lower part 136 of the casing pipe 132, and a suction pipe 48 is connected to the pumping pump 144.
[0032]
In such a structure, when pumping up groundwater, the pumping well 32 sealed on the ground surface is decompressed by a decompression pump (not shown) and kept in a vacuum state, and the pumping effect is increased by the vacuum effect. be able to. When the pumping pump 144 is operated and sucked in such a reduced pressure or vacuum state, the groundwater in the pumping well 32 flows into the inside through the multiple slits 140 of the slit pipe 138 and further passes through the inlet 142 of the casing pipe 132 to the inside. The groundwater thus introduced is sucked in by the pumping pump 144 and flows downstream through the suction pipe 48 as indicated by an arrow. At this time, when flowing in through the slit 140 of the slit tube 132, the inflow of air contained in the groundwater is substantially blocked, and the groundwater from which the air has been separated is fed to the pumping pump 144, thereby increasing the pumping efficiency. , Can pump a large volume of groundwater. Compared to conventional groundwater pumping by gravity drainage, this method performs forced drainage using atmospheric pressure, so it has a large consolidation dewatering effect and has a large capacity to collect water, so it can pump large volumes of groundwater.
[0033]
Further, in order to further reduce the size of bubbles contained in the liquid, a large number of fines are provided at the tip of the liquid supply pipe (2, 4 etc.), in other words, the inlet of the pipe for injecting the liquid containing bubbles into the ground. It is preferable to provide a fine bubble generating member (not shown) having a hole, and by providing the fine bubble generating member, when injected into the ground, liquid containing fine bubbles is supplied to the liquid supply pipe (2, 4). Etc.) is injected into the ground through a large number of micropores of the microbubble generating member, and the bubbles in the liquid are subdivided by passing through the microbubble generating member, thus further miniaturizing the bubbles in the liquid. Can do. The fine bubble generating member can be formed from sintered steel, a resin plate, a resin film, and the like, and can be widely applied to the first to fourth embodiments described above.
[0034]
As mentioned above, although the Example of the purification method of the soil and groundwater according to this invention was described, this invention is not limited to this Example, A various deformation | transformation thru | or correction | amendment are possible, without deviating from the scope of the present invention.
For example, in the second to fourth embodiments, the pumping well 32 as a pumping hole is excavated and the groundwater accumulated in the pumping well 32 is pumped up. It is also possible to bury a pumping pipe, form a pumping hole by this pumping pipe, and pump up groundwater from this pumping hole.
[0035]
For example, in the above-described embodiment, the liquid containing fine bubbles is injected into the ground through the tip (injection port) of the liquid supply pipe (2, 4 etc.). It may be allowed to penetrate into the ground.
[0036]
  According to the soil and groundwater purification method of claim 1 of the present invention, the liquid containing fine bubbles having a size of 1 to 10,000 μm is injected or infiltrated into the ground. The ascending speed is slow and also diffuses laterally in the ground, which promotes the uniform supply of oxygen into the ground. As a result, the growth or activity of microorganisms in the ground is activated, the purification action by microorganisms is enhanced, and contaminated soil and / or contaminated groundwater can be efficiently purified using microorganisms.Also, an air supply pipe is arranged inside the liquid supply pipe in the radial direction, and the air from the air supply pipe is mixed with the liquid from the liquid supply pipe at the tip of the liquid supply pipe. The liquid supply pipe and the air supply pipe can be embedded in the ground relatively easily.
[0037]
According to the soil and groundwater purification method of claim 2 of the present invention, the liquid containing fine bubbles is substantially uniformly dispersed in the region to be purified, and thus the microorganisms present in the region are dispersed. Is activated and can be purified substantially uniformly over the entire area to be cleaned.
[0038]
  Moreover, according to the soil and groundwater purification method of claim 3 of the present invention, the liquid containing fine bubbles having a size of 1 to 10000 μm is injected or infiltrated into the ground. The rising speed is slow and the liquid containing fine bubbles flows through the area to be purified. Accordingly, the region to be purified, that is, the contaminant contained in the soil and / or the contaminant attached to the soil surface is cleaned by the flow of the liquid and the flow of the fine bubbles contained therein. Moreover, this fine bubble can invade between narrow soil particles by the flow of the liquid, and the purification ability can be enhanced.Also, an air supply pipe is arranged inside the liquid supply pipe in the radial direction, and the air from the air supply pipe is mixed with the liquid from the liquid supply pipe at the tip of the liquid supply pipe. The liquid supply pipe and the air supply pipe can be embedded in the ground relatively easily.
  According to the soil and groundwater purification method of claim 4 of the present invention, the groundwater is circulated through the region to be purified, and the region to be purified using the groundwater, that is, contaminated soil and / or contaminated groundwater is required. Can be purified on the street.
[0039]
Moreover, according to the soil and groundwater purification method of claim 5 of the present invention, the nutrient substance added to the groundwater is given to the microorganisms in the soil, and the proliferation or activity of the microorganisms is further activated, and the purification by the microorganisms is performed. The effect can be further enhanced.
Moreover, according to the soil and groundwater purification method of claim 6 of the present invention, a large amount of groundwater can be pumped because the groundwater is pumped in a reduced pressure state using the vacuum pump.
[0040]
  According to the soil and groundwater purification method of claim 7 of the present invention, heavy metals in the groundwater are removed by a heavy metal treatment device, oil in the groundwater is removed by an oil removal device, and the groundwater from which these have been removed is removed from the ground. So that the area to be purified can be purified more effectively.wear.
  Furthermore,According to the method for purifying soil and groundwater according to claim 8 of the present invention, since the fine bubble generating member is provided at the tip of the pipe for injecting the liquid, the bubbles in the liquid are made finer and in the ground Can be injected into.
[Brief description of the drawings]
FIG. 1 is a plan view schematically showing a first embodiment of a soil and groundwater purification system to which a first embodiment of a soil and groundwater purification method according to the present invention is applied;
FIG. 2 is a cross-sectional view schematically showing the soil and groundwater purification system of FIG. 1;
FIG. 3 is a sectional view schematically showing a part of a second embodiment of a soil and groundwater purification system to which a second embodiment of the soil and groundwater purification method according to the present invention is applied;
FIG. 4 is a sectional view schematically showing a part of a third embodiment of a soil and groundwater purification system to which a third embodiment of the soil and groundwater purification method according to the present invention is applied;
FIG. 5 is a sectional view schematically showing a part of a fourth embodiment of a soil and groundwater purification system to which a fourth embodiment of the soil and groundwater purification method according to the present invention is applied;
FIG. 6 is a cross-sectional view schematically showing a modified form of a pumping portion of a pumping well.
[Explanation of symbols]
1 Main liquid supply pipe
2,4 Branch liquid supply pipe
5,7 Air supply pipe
6 Air injection mechanism
8 Areas to be purified
32 Pumping well
46 Groundwater
52,82 Liquid supply pipe
54,84 Air supply pipe
92 Oil remover
94 Heavy metal processing equipment

Claims (8)

An air supply pipe for supplying air is disposed inside the liquid supply pipe for supplying liquid and is embedded in the ground, and the air supply pipe is supplied to the liquid flowing through the liquid supply pipe at the tip of the liquid supply pipe. By mixing the air flowing through the liquid and mixing the liquid and air, a liquid containing fine bubbles having a size of 1 to 10,000 μm is injected or penetrated into the ground, and the rising speed of the fine bubbles contained in the liquid is reduced. It is characterized by the fact that the oxygen supply to the ground is made uniform by diffusing in the lateral direction, thereby decomposing and purifying the soil by activating the growth or activity of microorganisms that decompose the pollutants contained in the ground. Soil and groundwater purification methods.   2. The method for purifying soil and groundwater according to claim 1, wherein a liquid containing fine bubbles is dispersed substantially uniformly in a region to be purified in the ground. An air supply pipe for supplying air is disposed inside the liquid supply pipe for supplying liquid and is embedded in the ground, and the air supply pipe is supplied to the liquid flowing through the liquid supply pipe at the tip of the liquid supply pipe. By mixing the air flowing through the liquid and mixing the liquid and air, a liquid containing fine bubbles having a size of 1 to 10,000 μm is injected or penetrated into the ground, and the rising speed of the fine bubbles contained in the liquid is reduced. Then, the liquid is allowed to diffuse laterally and flow through a region to be purified in the ground, and this liquid flow cleans and purifies contaminants contained in the soil and / or adhering to the soil surface, and fine bubbles and / or purification method of soil and ground water, wherein the or infiltrating oxygen by fine bubbles between narrow soil particles.   Using groundwater as a liquid containing fine bubbles, providing a pumping hole in relation to the area to be purified, making the groundwater pumped from this pumping hole contain fine bubbles, and then injecting or penetrating into the ground, The method for purifying soil and groundwater according to any one of claims 1 to 3, wherein groundwater is circulated through the region to be purified.   5. The method for purifying soil and groundwater according to claim 4, wherein nutrients of decomposing microorganisms are added to the groundwater pumped from the pumping hole and then injected or infiltrated into the ground.   The soil and groundwater according to claim 4 or 5, wherein a decompression pump is used to decompress the pumping hole, groundwater is pumped in a decompressed state by the decompression pump, and the pumped groundwater is injected or infiltrated into the ground. Purification method.   Groundwater pumped from the pumping hole is allowed to flow through a heavy metal treatment device and an oil removal device, heavy metal contained in the groundwater is removed by the heavy metal treatment device, oil contained in the groundwater is removed by the oil removal device, and heavy metal and oil content are removed. The method for purifying soil and groundwater according to any one of claims 4 to 6, wherein air is included in the groundwater from which water has been removed. The soil according to any one of claims 1 to 7 , wherein a fine bubble generating member having a large number of fine holes is provided at a tip portion of a pipe for injecting a liquid containing fine bubbles into the ground. Groundwater purification method.

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