JP7193987B2 - Well structure, groundwater purification system and groundwater purification method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a well structure, a groundwater purification system, and a groundwater purification method.

Conventionally, as a method for purifying polluted groundwater, it is known to pump up groundwater from a pumping well, purify it with facilities above ground, and return it underground from an injection well.

In addition, multiple wells are installed in the ground divided vertically by impermeable materials, chemicals are injected into each well, and groundwater from the upper part of the well is sent to the lower part of the well, adjacent to the other well. In other wells, it is proposed that groundwater from the lower part is sent to the upper part to generate a circulating flow between adjacent wells to uniformly infiltrate the chemical into the ground (for example, Patent Document 1) reference).

Japanese Patent No. 5711519

However, in the purification method described in Patent Document 1, the lower part of the well becomes a closed area by partitioning the inside of the well with a water impermeable material. Therefore, when the groundwater from the upper part of the well is sent to the lower part, the water pressure rises in the closed area, and there is a possibility that the well structure will be damaged, the groundwater will be blown out, and the risk of leakage of groundwater containing harmful substances will increase.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and aims to provide a well structure, a groundwater purification system, and a groundwater treatment system capable of preventing an increase in water pressure in a well and safely and quickly purifying groundwater. To provide a purification method.

In order to achieve the above-mentioned object, the first invention includes a water impermeable material that divides a well installed in the ground into two sections in the depth direction, and a An outer tube provided with a strainer and having a lower end located on the upper surface of the water impermeable material, and a strainer disposed in the outer tube and having a top end lower than the top end of the outer tube and below the water impermeable material. and a double pipe in which the top end of the outer pipe and the top end of the inner pipe are open, and a section located inside or outside the double pipe and above the waterproof material and a pump for moving water between and a lower section, wherein the inner pipe penetrates the impermeable material, and the space between the outer pipe and the inner pipe is at least the impermeable material It is a well structure characterized by being partially blocked.

In the first invention, the top end of the outer pipe and the top end of the inner pipe of the double pipe provided in the well are open, and the inner pipe penetrates the impermeable material that divides the well into two sections in the depth direction. , the section below the impermeable material is not a closed area. Therefore, when the pump is used to move water from the upper section to the lower section, it is possible to prevent an increase in water pressure in the well. In addition, since the top of the inner pipe is lower than the top of the outer pipe, when using a pump to move water between the inner pipe and the outer pipe, even if the water level inside the destination pipe rises, No water leakage. Furthermore, by placing the impermeable material above the strainer of the inner pipe and below the strainer of the outer pipe, and blocking the space between the outer pipe and the inner pipe with a part of the impermeable material, the section above the well groundwater movement other than pumping from the pump can be blocked between the lower section.

The pump comprises, for example, a first pump arranged inside the outer tube in the upper section and a second pump arranged inside the inner tube in the lower section, Operation of either the first pump or the second pump switches the direction of water movement between the upper section and the lower section.
This makes it possible to easily switch the direction of water movement within the double pipes in the same well structure.

When the pump has the above configuration, a communicating portion for communicating between the inside of the outer pipe and the inside of the inner pipe is provided at a position lower than the top end of the inner pipe. A water pipe for moving the water pumped by the pump of No. 2 may be arranged in the communicating portion.
As a result, the lift of the pump becomes smaller than when the water pipe is arranged straddling the top end of the inner pipe. Therefore, a pump with a small capacity can be used, and the cost can be suppressed.

The pump may be arranged above the top end of the double pipe, and the direction of movement of water between the upper section and the lower section may be switched by changing the operating direction of the pump. .
This makes it possible to easily switch the direction of water movement within the double pipes in the same well structure. In addition, compared to the case where the pump is arranged inside the double pipe, the diameter of the well can be made smaller, and construction costs can be reduced.

A drug injection pump installed on the ground may be further provided, and the drug may be injected into the double tube using the drug injection pump.
This allows the drug to diffuse into the water moving within the well structure.

A second invention includes a water impermeable material that divides a well installed in the ground into two sections in the depth direction, and a strainer that is disposed in the well, is provided above the water impermeable material, and has a lower end portion as described above . an outer pipe positioned on the upper surface of the impermeable material; and a strainer disposed in the outer pipe, the strainer having a top end lower than the top end of the outer pipe and below the impermeable material, and a lower end positioned at the bottom of the well. and a double pipe in which the top end of the outer pipe and the top end of the inner pipe are open, and a section located inside or outside the double pipe and above the waterproof material and a pump for moving water between and a lower section, wherein the inner pipe penetrates the impermeable material, and the space between the outer pipe and the inner pipe is at least the impermeable material Well structures partially blocked are installed at a plurality of locations on the ground, chemical injection pumps for injecting a chemical into the double pipes of the plurality of well structures are installed on the ground, and the pumps of the plurality of well structures are installed. is controlled so that the water moving direction in one well structure among the plurality of well structures and the water moving direction in the other well structure adjacent to the one well structure are vertically reversed. This groundwater purification system is characterized by:

In the second invention, the well structure of the first invention is installed at a plurality of locations on the ground, and the direction of water movement in one well structure among the plurality of well structures and the other well structure adjacent to the one well structure. By controlling the direction of movement of water in the wells to be upside down, it is possible to generate a circulating flow that is substantially perpendicular to the flow of groundwater between adjacent wells. In addition, since the chemical agent is injected from the chemical injection pump into the well-structured double pipe, the chemical agent can be diffused into the ground due to the circulation flow.

A third invention includes a water impermeable material that divides a well installed in the ground into two sections in the depth direction, and a strainer that is arranged in the well and has a strainer above the water impermeable material and a lower end portion of the water impermeable material. an outer pipe positioned on the upper surface of the impermeable material; and a strainer disposed in the outer pipe, the strainer having a top end lower than the top end of the outer pipe and below the impermeable material, and a lower end positioned at the bottom of the well. and a double pipe in which the top end of the outer pipe and the top end of the inner pipe are open, and a section located inside or outside the double pipe and above the waterproof material and a pump for moving water between and a lower section, wherein the inner pipe penetrates the impermeable material, and the space between the outer pipe and the inner pipe is at least the impermeable material Step a of installing a plurality of said well structures in said ground using a partially blocked well structure; Step b of installing a chemical infusion pump on the ground; While injecting the drug into the double tube of the structure, the pumps of the plurality of well structures are controlled in the direction of water movement in one of the plurality of well structures and in the other adjacent to the one well structure. A groundwater purification method characterized by comprising a step c of controlling the direction of movement of water in the well structure to be vertically reversed.

In the third invention, the well structure of the first invention is installed at a plurality of locations on the ground, and the direction of water movement in one well structure among the plurality of well structures and the other well structure adjacent to the one well structure. By controlling the direction of movement of water in the wells to be upside down, it is possible to generate a circulating flow that is substantially perpendicular to the flow of groundwater between adjacent wells. In addition, since the chemical injection pump injects the chemical into the well-structured double pipe, the chemical can be diffused into the ground by a circulating flow.

Advantageous Effects of Invention According to the present invention, it is possible to provide a well structure, a groundwater purification system, and a groundwater purification method capable of preventing an increase in water pressure in the well and safely and quickly purifying groundwater.

The figure which shows the well structure 2. FIG. The figure which shows the movement condition of the water around the well structure 2 at the time of pump operation. The figure which shows the groundwater purification system 41. FIG. The figure which shows the groundwater purification system 41a. The figure which shows the groundwater purification system 41b. The figure which shows the well structure 2c.

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described in detail below based on the drawings.

(1. Well structure 2)
FIG. 1 shows a well structure 2 according to a first embodiment of the invention. FIG. 1 shows a vertical cross-section of the ground 1 . As shown in FIG. 1, the well structure 2 includes a well 3, a double pipe 5, a water impermeable material 23, a first pump 31-1, a second pump 31-2, a chemical injection pump 37, and the like. .

A well 3 is dug vertically in the ground 1 . The impermeable material 23 divides the well 3 into two sections 25-1 and 25-2 in the depth direction. The double pipe 5 consists of an outer pipe 7 arranged inside the well 3 and an inner pipe 15 arranged inside the outer pipe 7 .

The lower end portion of the outer pipe 7 is located on the upper surface of the waterproof material 23 . The inner pipe 15 is arranged to pass through the impermeable material 23 and has its lower end positioned at the bottom of the well 3 . That is, the impermeable material 23 is provided between the outer peripheral surface of the inner pipe 15 and the hole wall of the well 3, and a part of the impermeable material 23 is located at the lower end of the space 8 between the outer pipe 7 and the inner pipe 15. block the part A top end 9 of the outer tube 7 is positioned near the surface of the ground 1 . A top end 17 of the inner tube 15 is positioned lower than a top end 9 of the outer tube 7 . A top end 9 of the outer tube 7 and a top end 17 of the inner tube 15 are open.

The portion of the outer pipe 7 above the impermeable material 23 is the strainer pipe 13 . A plurality of holes 11 are provided in the strainer tube 13 . The portion of the inner pipe 15 below the impermeable material 23 is the strainer pipe 21 . A plurality of holes 19 are provided in the strainer tube 21 . A water impermeable material 24 is provided between the outer peripheral surface of the portion of the outer pipe 7 above the strainer pipe 13 and the hole wall of the well 3 . The impermeable material 24 prevents rainwater or the like from flowing into the vicinity of the strainer pipe 13 from the ground surface.

In the section 25-1 above the impermeable material 23, silica sand 27 is filled between the outer peripheral surface of the outer pipe 7 and the hole wall of the well 3. As shown in FIG. Silica sand 29 is filled between the outer peripheral surface of the inner pipe 15 and the hole wall of the well 3 in the section 25 - 2 below the impermeable material 23 .

The pump 31-1 is arranged below the space 8 between the outer pipe 7 and the inner pipe 15 in the section 25-1 above the impervious material . A water pressure gauge 33-1 is also arranged in the lower part of the space 8. FIG. The pump 31-2 is arranged below the space 16 inside the inner pipe 15 in the section 25-2 below the impermeable material . A water pressure gauge 33-2 is also arranged in the lower part of the space 16. FIG. The pumps 31 - 1 and 31 - 2 are connected to a water pipe 35 arranged across the top end 17 of the inner pipe 15 .

A drug injection pump 37 is installed on the ground 1 . One end of a drug injection tube 39 is connected to the drug injection pump 37 , and the other end of the drug injection tube 39 is arranged inside the double tube 5 .

To construct the well structure 2, first, a well 3 is excavated in the ground 1, and an inner pipe 15 is erected in the well 3. Then, the space between the outer peripheral surface of the inner pipe 15 and the hole wall of the well 3 is filled with silica sand 29 to a predetermined depth, and the impervious material 23 is installed above the silica sand 29 . Next, the outer pipe 7 is erected outside the inner pipe 15 . After that, the space between the outer peripheral surface of the outer tube 7 and the hole wall of the well 3 is filled with silica sand 27 to a predetermined depth, and a water-impermeable material 24 is installed above the silica sand 27, and above the water-impermeable material 24. is filled with silica sand 27 .

Further, after erecting the outer pipe 7, the water pipe 35, the pump 31-1, and the water pressure gauge 33-1 are installed in the space 8, and the water pipe 35, the pump 31-2, and the water pressure gauge 33-2 are installed in the space 16. Install. Furthermore, a drug injection pump 37 is installed on the ground, and a drug injection tube 39 is inserted into the double tube 5 .

FIG. 2 is a diagram showing how water moves around the well structure 2 during pump operation, and shows a vertical cross section of the ground 1. As shown in FIG. FIG. 2(a) is a diagram showing a state in which the pump 31-1 is in operation, and the illustration of the pump 31-2 and water pressure gauge 33-1 is omitted. In the example shown in FIG. 2( a ), the pump 31 - 1 is operated to move the water pumped from the space 8 to the space 16 through the water pipe 35 . Then, around the well structure 2, as indicated by arrows, water infiltrates from the ground 1 into the space 8 and seeps out from the space 16 into the ground 1 at the same time.

At this time, the water pressure is measured using the water pressure gauge 33-2, and the flow rate of the pump 31-1 is adjusted so that the water level in the space 16 does not become too high. In addition, the chemical injection pipe 39 is arranged in the space 16 to which the pumped water is moved, and the chemical is injected and leached into the ground 1 together with the water.

FIG. 2(b) is a diagram showing a state in which the pump 31-2 is in operation, and the illustration of the pump 31-1 and water pressure gauge 33-2 is omitted. In the example shown in FIG. 2(b), the pump 31-2 is operated to move the water pumped from the space 16 to the space 8 through the water pipe . Then, around the well structure 2, as indicated by the arrows, water infiltrates from the ground 1 into the space 16 and seeps out from the space 8 into the ground 1 at the same time.

At this time, the water pressure is measured using the water pressure gauge 33-1, and the flow rate of the pump 31-2 is adjusted so that the water level in the space 8 does not become too high. In addition, the chemical injection pipe 39 is placed in the space 8 to which the pumped water is moved, and the chemical is injected and leached into the ground 1 together with the water.

As shown in FIG. 2, in well structure 2, the direction of water movement is switched between section 25-1 and section 25-2 by operating either pump 31-1 or pump 31-2. be done.

(2. Groundwater purification system 41)
FIG. 3 is a diagram showing the groundwater purification system 41, showing a vertical cross section of the ground 1. As shown in FIG. The groundwater purification system 41 consists of two well structures 2 installed in the ground 1, chemical injection pumps 37, and the like.

The well structures 2-1 and 2-2 are arranged such that the surfaces containing the respective wells 3 are substantially perpendicular to the direction of flow of the contaminated groundwater. Well structures 2-1 and 2-2 share drug injection pump 37, drug injection tube 39-1 is inserted into well structure 2-1, and drug injection tube 39-2 is inserted into well structure 2-2. inserted.

When purifying the groundwater in the ground 1, the groundwater purification system 41, as shown in FIG. The pump is controlled so that the direction of movement of water is the upside down direction. For example, the pump 31-1 is operated in the well structure 2-1 (the pump 31-2 and the water pressure gauge 33-1 are not shown), and the well structure 2-2 (the pump 31-1 and the water pressure gauge 33-2 are not shown). ) to drive the pump 31-2.

Then, the same movement of water as shown in FIG. 2(a) occurs around the well structure 2-1, and the same movement of water as shown in FIG. 2(b) occurs around the well structure 2-2. occur. Then, as shown in FIG. 3, in the ground 1, the horizontal flow from the space 8 of the well structure 2-2 to the space 8 of the well structure 2-1 and the flow from the space 16 of the well structure 2-1 to the well Circulating flow occurs due to horizontal flow into space 16 of structure 2-2.

Further, in the groundwater purification system 41, the chemical is injected from the chemical injection pump 37 into the space 16 of the well structure 2-1 through the chemical injection pipe 39-1, and the chemical is injected into the space 16 of the well structure 2-1 through the chemical injection pipe 39-2. A drug is injected into the space 8 of 2. The chemical is uniformly diffused in the ground 1 by the circulating flow indicated by the arrows in FIG. 3 described above.

The drug injected from the drug injection pump 37 is selected according to the contaminants to be purified. For example, if volatile organic chlorine compounds (VOC) in the groundwater of the ground 1 are to be purified, it is desirable to use an activator that activates anaerobic microorganisms as the chemical. If an activator that activates anaerobic microorganisms is diffused in the ground 1, VOCs in groundwater are decomposed by the action of the anaerobic microorganisms.

If benzene, oil, or the like in the groundwater of the ground 1 is to be purified, it is desirable to use a nutrient salt as a chemical and send air through the double pipe 5 to raise the dissolved oxygen concentration in the groundwater. If nutrient salts and dissolved oxygen that activate aerobic microorganisms are diffused in the ground 1, benzene, oil, and the like in groundwater are decomposed by the action of the aerobic microorganisms.

During the operation of the groundwater purification system 41, the concentration of chemicals in the groundwater is measured as necessary. In order to measure the chemical concentration, while the pumps 31-1 and 31-2 are operating in the well structures 2-1 and 2-2, the chemical injection pump 37 is temporarily stopped and the groundwater in the double pipe 5 is measured. to collect. Then, the concentration of the drug in the groundwater is measured using a measuring device (not shown). At this time, the concentration of contaminants to be purified may also be measured.

In the groundwater purification system 41, the moving direction of water may be switched as needed. To switch the water movement direction from the state shown in FIG. 3, the pump 31-2 (not shown) is operated in the well structure 2-1, and the pump 31-1 (not shown) is operated in the well structure 2-2. . As a result, in the ground 1, the horizontal flow from the space 8 of the well structure 2-1 to the space 8 of the well structure 2-2 and the flow from the space 16 of the well structure 2-2 to the space of the well structure 2-1 Circulating flow occurs due to horizontal flow to 16 .

Thus, in the well structure 2 used in the first embodiment, the top end 9 of the outer pipe 7 and the top end 17 of the inner pipe 15 of the double pipe 5 provided in the well 3 are open to open the well 3. Since the inner pipe 15 penetrates the impermeable material 23 divided into two sections 25-1 and 25-2 in the depth direction, the section 25-2 below the impermeable material 23 does not become a closed area. Therefore, when the pump 31-1 is used to move water from the space 8 of the section 25-1 to the space 16 of the section 25-2, the condition that water is less likely to seep from the section 25-2 in the well 3 to the ground 1 Even if it is, it is possible to prevent an increase in water pressure in section 25-2.

Further, by making the top end 17 of the inner pipe 15 lower than the top end 9 of the outer pipe 7, the water level in the space 16 and the space 8 rises due to the movement of water using the pumps 31-1 and 31-2. water will not leak to the ground. Furthermore, the impermeable material 23 is arranged above the strainer pipe 21 of the inner pipe 15 and below the strainer pipe 13 of the outer pipe 7, and the space 8 between the outer pipe 7 and the inner pipe 15 is part of the impermeable material 23. By blocking with the part, it is possible to block the movement of water without using the water pipe 35 between the section 25-1 and the section 25-2.

In the groundwater purification system 41 of the first embodiment, two well structures 2 are arranged in the ground 1, and the water moving direction in the well structure 2-1 and the water moving direction in the adjacent well structure 2-2 By controlling the operation of the pumps 31-1 and 31-2 so that the flow direction of the pumps 31-1 and 31-2 is reversed, the flow of groundwater is substantially perpendicular to the flow of groundwater in the ground 1 between the well structures 2-1 and 2-2. A circulating flow can be generated. Further, by injecting a chemical agent into the double pipe 5, the chemical agent can be homogeneously diffused in the ground 1 by a circulating flow to purify groundwater.

In each well 3, only one of the pumps 31-1 and 31-2 may be installed instead of both. In this case, the pumps 31-1 and 31-2 may be alternately arranged for the wells 3 adjacent to each other. In this way, although the direction of movement of water cannot be switched, a circulation flow that is substantially perpendicular to the flow of groundwater is generated in the ground 1 between the adjacent well structures 2-1 and 2-2. be able to.

Other examples of the present invention will be described below as second to fourth embodiments. In each embodiment, points different from the embodiments described so far will be described, and descriptions of similar configurations will be omitted by attaching the same reference numerals in the drawings and the like.

First, the second embodiment will be described. FIG. 4 is a diagram showing a groundwater purification system 41a of a second embodiment, showing a cross section of the ground 1 in the vertical direction. The groundwater purification system 41a consists of two well structures 2a installed in the ground 1, chemical injection pumps 37, and the like.

The well structure 2a is provided with a communicating portion 43 at a position lower than the top end 17 of the inner pipe 15 for communicating the space 8 between the outer pipe 7 and the inner pipe 15 and the space 16 inside the inner pipe 15, It differs from the well structure 2 of the first embodiment in that a water pipe 35a for moving the water pumped by the pumps 31-1 and 31-2 is arranged in the communicating portion 43. FIG.

In the groundwater purification system 41a, the well structures 2a-1 and 2a-2 are arranged so that the plane containing each well 3 is substantially perpendicular to the direction of flow of contaminated groundwater. Well structures 2a-1 and 2a-2 share drug injection pump 37, drug injection tube 39-1 is inserted into well structure 2a-1, and drug injection tube 39-2 is inserted into well structure 2a-2. inserted.

When purifying the groundwater in the ground 1, in the groundwater purification system 41a, as in the first embodiment, the direction of water movement in the well structure 2a-1 and the well structure 2a-2 adjacent to the well structure 2a-1 Control the pump so that the direction of water movement in For example, the pump 31-1 is operated in the well structure 2a-1 (the pump 31-2 and the water pressure gauge 33-1 are not shown), and the well structure 2a-2 (the pump 31-1 and the water pressure gauge 33-2 are not shown). ) to drive the pump 31-2.

Then, as shown in FIG. 4, in the ground 1, a horizontal flow from the space 8 of the well structure 2a-2 to the space 8 of the well structure 2a-1 and a flow from the space 16 of the well structure 2a-1 to the well Circulating flow occurs due to horizontal flow into space 16 of structure 2a-2.

Further, in the groundwater purification system 41a, the chemical is injected from the chemical injection pump 37 into the space 16 of the well structure 2a-1 through the chemical injection pipe 39-1, and the chemical is injected into the well structure 2a- through the chemical injection pipe 39-2. A drug is injected into the space 8 of 2. The chemical is uniformly diffused in the ground 1 by the circulating flow indicated by the arrows in FIG.

In the groundwater purification system 41a, the moving direction of water may be switched as needed. In order to switch the direction of water movement from the state shown in FIG. 4, the pump 31-2 (not shown) is operated in the well structure 2a-1, and the pump 31-1 (not shown) is operated in the well structure 2a-2. . As a result, in the ground 1, the horizontal flow from the space 8 of the well structure 2a-1 to the space 8 of the well structure 2a-2 and the flow from the space 16 of the well structure 2a-2 to the space of the well structure 2a-1 Circulating flow occurs due to horizontal flow to 16 .

The well structure 2a used in the second embodiment also provides the same effects as the well structure 2 of the first embodiment. Further, in the well structure 2a, the water pipe 35a is arranged in the communicating portion 43 at a position lower than the top end 17 of the inner pipe 15, so that the water pipe 35 is placed across the top end 17 of the inner pipe 15. Compared to Structure 2, the pumps 31-1 and 31-2 have smaller lifts. Therefore, the pumps 31-1 and 31-2 with small capacity can be applied, and the cost can be suppressed.

In the groundwater purification system 41a of the second embodiment as well, the pump 31-1 is arranged such that the water moving direction in the well structure 2a-1 and the water moving direction in the adjacent well structure 2a-2 are vertically reversed. , 31-2, it is possible to generate a circulation flow substantially perpendicular to the groundwater flow in the ground 1 between the well structures 2a-1 and 2a-2. Further, by injecting a chemical agent into the double pipe 5, the chemical agent can be homogeneously diffused in the ground 1 by a circulating flow to purify groundwater.

Next, a third embodiment will be described. FIG. 5 is a diagram showing a groundwater purification system 41b of a third embodiment, showing a cross section of the ground 1 in the vertical direction. The groundwater purification system 41b consists of two well structures 2b installed in the ground 1, chemical injection pumps 37, and the like.

In the well structure 2b, the well 3b is vertically excavated below the recess 45 provided in the surface of the ground 1, the top of the double pipe 5b is located on the bottom surface of the recess 45, and the pump 31b is inside the recess 45, i.e. It differs from the well structure 2 of the first embodiment in that it is provided outside the double pipe 5b.

Two water pipes 35b are connected to the pump 31b. The lower end of one of the two water pipes 35 b is positioned near the bottom of the space 8 , and the lower end of the other water pipe 35 b is positioned near the bottom of the space 16 . The pump 31b can switch the moving direction of water between the space 8 and the space 16 .

In the groundwater purification system 41b, the well structures 2b-1 and 2b-2 are arranged so that the plane containing each well 3 is substantially perpendicular to the direction of flow of contaminated groundwater. Well structures 2b-1 and 2b-2 share drug injection pump 37, drug injection tube 39-1 is inserted into well structure 2b-1, and drug injection tube 39-2 is inserted into well structure 2b-2. inserted.

When purifying the groundwater in the ground 1, in the groundwater purification system 41b, the direction of water movement in the well structure 2b-1 and the direction of water movement in the well structure 2b-2 adjacent to the well structure 2b-1 are up and down. The pump 31b is operated in the opposite direction. For example, in the well structure 2b-1, the pump 31b is operated to pump water from the space 8 through the water pipe 35b and move it to the space 16, and in the well structure 2b-2, water is pumped up from the space 16 through the water pipe 35b. The pump 31b is operated so as to feed the water to the space 8.

Then, around the well structure 2b-1, water infiltrates from the ground 1 into the space 8 and seeps out from the space 16 into the ground 1 at the same time. Around the well structure 2b-2, water infiltrates from the ground 1 into the space 16 and seeps out from the space 8 into the ground 1 at the same time. Then, as shown in FIG. 5, in the ground 1, the horizontal flow from the space 8 of the well structure 2b-2 to the space 8 of the well structure 2b-1 and the flow from the space 16 of the well structure 2b-1 to the well structure 2b-1 Circulating flow occurs due to horizontal flow into space 16 of structure 2b-2.

At this time, the water pressure is measured using the water pressure gauge 33-2 in the well structure 2b-1, and the flow rate of the pump 31b is adjusted so that the water level in the space 16 does not become too high. In the well structure 2b-2, the water pressure is measured using the water pressure gauge 33-1, and the flow rate of the pump 31b is adjusted so that the water level in the space 8 does not become too high.

Further, in the groundwater purification system 41b, the chemical is injected from the chemical injection pump 37 into the space 16 of the well structure 2b-1 through the chemical injection pipe 39-1, and the chemical is injected into the well structure 2b- through the chemical injection pipe 39-2. A drug is injected into the space 8 of 2. The chemical is uniformly dispersed in the ground 1 by the circulation flow indicated by the arrows in FIG.

In the groundwater purification system 41b, the moving direction of water may be switched as needed. To switch the direction of movement of water from the state shown in FIG. 5, the operating direction of the pump 31b is switched in each of the well structures 2b-1 and 2b-2. As a result, in the ground 1, a horizontal flow from the space 8 of the well structure 2b-1 to the space 8 of the well structure 2b-2 and from the space 16 of the well structure 2b-2 to the space of the well structure 2b-1 Circulating flow occurs due to horizontal flow to 16 .

The well structure 2b used in the third embodiment also provides the same effects as the well structure 2 of the first embodiment. In the well structure 2b, the pump 31b is arranged in the recess 45 above the double pipe 5b, so that the pumps 31-1 and 31-2 are arranged inside the double pipe 5. In comparison, the diameter of the well 3b can be made smaller. Therefore, construction costs can be reduced.

Also in the groundwater purification system 41b of the third embodiment, the pump 31b is operated such that the water moving direction in the well structure 2b-1 and the water moving direction in the adjacent well structure 2b-2 are vertically reversed. By controlling the operation, it is possible to generate a circulation flow substantially perpendicular to the groundwater flow in the ground 1 between the well structures 2b-1 and 2b-2. Further, by injecting a chemical agent into the double pipe 5b, the chemical agent can be homogeneously diffused in the ground 1 by a circulating flow to purify groundwater.

Next, a fourth embodiment will be described. FIG. 6 is a diagram showing a well structure 2c of the fourth embodiment, showing a cross section of the ground 1 in the vertical direction. As shown in FIG. 6, the well structure 2c is composed of the well 3, the double pipe 5c, the impermeable material 23c, the first pump 31-1, the second pump 31-2, and the like.

In the well structure 2c, the impermeable material 23c is divided into impermeable materials 23c-1 and 23c-2, and the double pipe 5c is arranged inside the outer pipe 7c arranged inside the well 3 and inside the outer pipe 7c. The well structure 2 differs from the well structure 2 of the first embodiment in that it is composed of an inner pipe 15 that

The outer pipe 7c is arranged to penetrate the impervious material 23c like the inner pipe 15, and the lower end is positioned at the bottom of the well 3. As shown in FIG. That is, the water-impermeable material 23c is provided between the outer peripheral surface of the inner pipe 15 and the hole wall of the well 3, and the outer water-impervious material 23c-1 of the water-impervious materials 23c is provided between the outer peripheral surface of the outer pipe 7c. The inner impervious material 23 c - 2 blocks the space 8 between the outer pipe 7 c and the inner pipe 15 by blocking the hole wall of the well 3 . The top end 9 of the outer pipe 7c is positioned near the surface of the ground 1 higher than the top end 17 of the inner pipe 15 and is open.

The portion of the outer pipe 7c above the impermeable material 23c is the strainer pipe 13, and the portion below the impermeable material 23c is the strainer pipe 13c. A plurality of holes 11 are provided in the strainer pipe 13, and a plurality of holes 11c are provided in the strainer pipe 13c. A water impermeable material 24 is provided between the outer peripheral surface of the portion of the outer pipe 7c above the strainer pipe 13 and the hole wall of the well 3 .

In the section 25-1 above the impermeable material 23, silica sand 27 is filled between the outer peripheral surface of the outer tube 7c and the hole wall of the well 3. As shown in FIG. Silica sand 29 is filled between the outer peripheral surface of the outer tube 7c and the hole wall of the well 3 in the section 25-2 below the impermeable material 23c.

To construct the well structure 2c, first, a well 3 is excavated in the ground 1, and a double pipe 5c composed of an inner pipe 15 and an outer pipe 7c is erected in the well 3. Then, the space between the outer peripheral surface of the outer tube 7c and the hole wall of the well 3 is filled with silica sand 29 to a predetermined depth, and above the silica sand 29, the impervious material 23c-1 is installed. After that, silica sand 27 is filled above the water-impervious material 23 c - 1 to a predetermined depth, the water-impervious material 24 is installed above the silica sand 27 , and the silica sand 27 is filled above the water-impervious material 24 .

Further, after erecting the double pipe 5c, a water impermeable material 23c-2 is installed between the outer peripheral surface of the inner pipe 15 and the inner peripheral surface of the outer pipe 7c, and the water pipe 35 and the pump 31- are placed in the space 8. 1. A water pressure gauge 33-1 is installed, and a water pipe 35, a pump 31-2, and a water pressure gauge 33-2 are installed in the space 16. Also, a drug injection pump (not shown) is installed on the ground, and a drug injection tube (not shown) is inserted into the double tube 5c.

When the pump 31-1 of the well structure 2c is operated to move the water pumped from the space 8 to the space 16 through the water pipe 35, in the section 25-2, the water flows from the space 16 through the hole 19 to the strainer pipe 13c. and the strainer tube 21 into the space 8c. Around the well structure 2c, water infiltrates from the ground 1 into the space 8 and seeps out from the space 16 into the ground 1 through the space 8c.

When the pump 31-2 of the well structure 2c is operated to move the water pumped from the space 16 to the space 8 through the water pipe 35, in the section 25-2, the water flows from the space 8c to the space 16 through the hole 19. Moving. Around the well structure 2c, water infiltrates into the space 16 from the ground 1 through the space 8c and seeps out from the space 8 into the ground 1 at the same time.

In the well structure 2c, the direction of water movement is switched between the sections 25-1 and 25-2 by operating either the pump 31-1 or the pump 31-2.

Even when the well structure 2c shown in FIG. 6 is used for a groundwater purification system, the water moving direction in one well structure 2c and the water moving direction in the other well structure 2c adjacent to the one well structure 2c are different. The operation of the pumps 31-1 and 31-2 is controlled so that the vertical direction is reversed. Also, a drug is injected into the double tube 5c of the well structure 2c from a drug injection pump (not shown).

Then, similarly to the groundwater purification system 41 of the first embodiment, a circulation flow is generated in the ground 1 between the two adjacent well structures 2c, and the chemical is uniformly diffused in the ground 1 by the circulation flow. .

The well structure 2c of the fourth embodiment also provides the same effect as the well structure 2 of the first embodiment. In the well structure 2c, since the outer pipe 7c is also arranged in the section 25-2, when the water is pumped up by the pump 31-1 and moved from the space 8 to the space 16, water also enters the space 8c. go. Therefore, compared to the well structure 2 in which only the inner pipe 15 is arranged in the section 25-2, the water level rise of the inner pipe 15 can be suppressed.

Even when a groundwater purification system is constructed using the well structure 2c of the fourth embodiment, the direction of water movement in one well structure 2c and the direction of water movement in the other well structure 2c adjacent to the one well structure 2c are different. By controlling the operation of the pumps 31-1 and 31-2 so that the movement direction is vertically reversed, a circulating flow that is substantially perpendicular to the groundwater flow is generated in the ground 1 between the two well structures 2c. can be generated. Further, by injecting the chemical agent into the double pipe 5c, the chemical agent can be homogeneously diffused in the ground 1 by a circulating flow to purify groundwater.

In the first to third embodiments, as shown in FIGS. 2 to 5, the chemical was injected into the space to which the water pumped by the pump is moved. good. For example, when a chemical is injected into the space from which water is moved (the space on the side where water is pumped up by a pump), the same effect can be obtained because the chemical is uniformly diffused by moving water within the double pipe.

Further, the number of well structures used in the groundwater purification system is not limited to two, and may be three or more. In this case also, by controlling the operation of the pump so that the direction of water movement is reversed between one well structure and another well structure adjacent to the one well structure, the adjacent well structures It is possible to purify groundwater in a wider area by generating a circulation flow in the ground between them.

Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited to such examples. It is obvious that a person skilled in the art can conceive of various modifications or modifications within the scope of the technical ideas disclosed in the present application, and these naturally belong to the technical scope of the present invention. Understood.

1…………Ground 2, 2-1, 2-2, 2a, 2a-1, 2a-2, 2b, 2b-1, 2b-2, 2c……Well structure 3, 3b…………Well 5, 5b, 5c... Double tube 7, 7c... Outer tube 9, 17... Top end 8, 8c, 16... Space 11, 11c, 19... Hole 13, 13c, 21... …Strainer pipe 15 …………Inner pipe 23, 23c, 23c-1, 23c-2, 24……Waterproof material 25-1, 25-2……Sections 27, 29……Silica sand 31-1, 31-2, 31b …… Pump 33-1, 33-2 …… Water pressure gauge 35, 35a, 35b …… Water pipe 37 …… Chemical injection pump 39, 39-1, 39-2 ………… Chemical injection pipes 41, 41a, 41b......Groundwater purification system 43......Communicating part 45......Recessed part

Claims (7)

A water impermeable material that divides a well installed in the ground into two sections in the depth direction,
an outer pipe arranged in the well, having a strainer provided above the impermeable material and having a lower end located on the upper surface of the impermeable material; a double pipe having an inner pipe provided with a strainer lower than an end and below the water impermeable material, wherein the top end of the outer pipe and the top end of the inner pipe are open;
a pump disposed inside or outside the double pipe to move water between a section above and a section below the impermeable material;
and
A well structure, wherein the inner pipe penetrates the impermeable material, and a space between the outer pipe and the inner pipe is closed by at least part of the impermeable material. the pump
a first pump disposed inside the outer tube in the upper section;
a second pump disposed inside the inner tube in the lower section;
consists of
2. The method of claim 1 , wherein the direction of water movement between said upper section and said lower section is switched by operating either said first pump or said second pump. well structure. A communication portion is provided at a position lower than the top end of the inner pipe for communicating the inside of the outer pipe with the inside of the inner pipe, and the water pumped by the first pump or the second pump is provided. 3. The well structure according to claim 2 , wherein a water pipe for movement is arranged in said communicating portion. The pump is arranged above the top end of the double pipe,
2. A well structure according to claim 1 , wherein the direction of movement of water between said upper section and said lower section is switched by changing the direction of operation of said pump. Further equipped with a drug infusion pump installed on the ground,
5. The well structure according to any one of claims 1 to 4 , wherein the drug is injected into the double pipe using the drug injection pump. A water impermeable material that divides a well installed in the ground into two sections in the depth direction,
an outer pipe arranged in the well, having a strainer provided above the impermeable material and having a lower end located on the upper surface of the impermeable material; and an inner pipe having a strainer provided lower than the end and below the water impermeable material and having a lower end positioned at the bottom of the well, and the top end of the outer pipe and the top end of the inner pipe are open. a tube;
a pump disposed inside or outside the double pipe to move water between a section above and a section below the impermeable material;
and
A well structure in which the inner pipe penetrates the impermeable material and a space between the outer pipe and the inner pipe is blocked by at least a part of the impermeable material is installed at a plurality of locations on the ground,
A drug injection pump for injecting a drug into the double pipe of the well structure is installed on the ground,
The plurality of well structure pumps are arranged such that the direction of movement of water in one well structure among the plurality of well structures and the direction of movement of water in the other well structure adjacent to the one well structure are vertically reversed. A groundwater purification system characterized by being controlled to be A water impermeable material that divides a well installed in the ground into two sections in the depth direction,
an outer pipe arranged in the well, having a strainer provided above the impermeable material and having a lower end located on the upper surface of the impermeable material; and an inner pipe having a strainer provided lower than the end and below the water impermeable material and having a lower end positioned at the bottom of the well, and the top end of the outer pipe and the top end of the inner pipe are open. a tube;
a pump disposed inside or outside the double pipe to move water between a section above and a section below the impermeable material;
and
Using a well structure in which the inner pipe penetrates the impermeable material and a space between the outer pipe and the inner pipe is blocked by at least a part of the impermeable material,
a step of installing a plurality of the well structures in the ground;
Step b of installing the drug infusion pump on the ground;
While injecting a chemical into the double pipes of the plurality of well structures using the chemical injection pump, the pumps of the plurality of well structures are operated in the moving direction of water in one well structure among the plurality of well structures. and a step c of controlling such that the movement direction of water in the other well structure adjacent to the one well structure is vertically reversed;
A groundwater purification method comprising:

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