JP2016168554A - Soil purification system and soil purification method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accelerate the purification of soil.SOLUTION: The underground water is pumped up through a withdrawal channel 3 and a lift pump 4, so that a clarifier injected from injection means 2 penetrates toward the withdrawal channel 3. During the penetration, the withdrawal is stopped (or the withdrawal amount is reduced), so that the flow of the clarifier is stopped (or the penetration rate of the clarifier is reduced) to accelerate the purification of the soil.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a soil purification system including an injection means for injecting a purification agent into soil, and a soil purification method.

  Conventionally, various soil purification systems and soil purification methods for purifying soil contaminated with VOC (volatile organic compounds) have been proposed (see, for example, Patent Document 1 and Non-Patent Document 1).

  FIG. 5 is a schematic diagram (side view) showing an example of a conventional configuration of a soil purification system, and reference numeral 102 denotes an injection means (sparging well) for injecting a liquid (nutrient brine) containing a nutrient source of microorganisms into the soil. The code | symbol 103 has shown the pumping well for pumping up groundwater. When the nutrient salt water is injected into the soil from the injection means 102, microorganisms living in the soil are activated and the pollutants are decomposed. The contaminated groundwater is pumped from the pumping well 103 by operating the pump 104 and sent to the water treatment device 106 via the water pipe 105.

Japanese Patent No. 4398699

Taisei Corporation, “Water Injection Biosparging Method”, [online], [Search February 17, 2015], Internet <http://www.taisei.co.jp/MungoBlobs/626/760/K00B90.pdf >

  However, the soil purification system as described above has a problem that the soil is not sufficiently purified.

  An object of this invention is to provide the soil purification system and soil purification method which can eliminate the above-mentioned problem.

The invention according to claim 1 is illustrated in FIGS. 1 (a) and 1 (b), and is a soil purification system for purifying soil in a predetermined area (see reference numeral A <b> 1, hereinafter referred to as “purification area”) ( In 1)
Injection means (2) arranged on one side of the purification area (A1) so as to inject the purification agent into the soil;
A pumping channel (3) that is installed in the soil on the other side of the purification area (A1) and constitutes a path of groundwater to the ground; and
A pump (4) connected to the pumping channel (3) and configured to pump groundwater from the pumping channel (3);
A pump operating part (7) for operating the pumping pump (4) so as to permeate the purification agent injected into the ground from the injection means (2) into the purification area (A1) side;
Pausing the pumping or reducing the pumping amount at the timing when it is determined that the purifying agent has penetrated from the injection means (2) side to the pumping channel part (3) side by a predetermined distance, and the pumping water is stopped. Or a pump control unit (8) for controlling the pump operating unit (7) so that pumping is resumed when a predetermined time has elapsed since the reduction of the pumping amount.

  The invention according to claim 2 is the timing according to the invention according to claim 1, wherein the pump control unit (8) is confirmed by monitoring that the concentration of the purifier has reached a predetermined concentration in the pumping channel unit (3). The pumping is stopped or the pumping amount is reduced.

  The invention according to claim 3 is the invention according to claim 1, wherein it is confirmed that the pump control unit (8) has reached a predetermined time when the amount of the pumped water has reached a predetermined amount and the time for performing the pumping. It is characterized in that the pumping is stopped or the pumping amount is reduced at a predetermined timing.

The invention according to claim 4 is a soil purification method for purifying soil in a predetermined area (see symbol A1 in FIG. 1B).
A step of injecting the purification agent into the soil via the injection means (2) arranged on one side of the purification area (A1) (see S1 in FIG. 4);
Permeating the injected purification agent by pumping groundwater through the pumping channel (3) that constitutes the route of groundwater to the ground by being installed in the soil on the other side of the purification area (A1) A purifier permeation step (see S2 in FIG. 4);
By stopping the pumping or reducing the pumping amount at the timing when it is determined that the cleaning agent has penetrated from the injection means (2) side to the pumping channel (3) side by a predetermined distance, A purification promoting step (see reference numerals S3 and S4 in FIG. 4) for stopping or slowing the penetration and promoting the purification of the soil by the penetration of the purification agent;
With
The soil purification in the purification area (A1) is performed while repeating the purification agent permeation step (S2) and the purification promotion step (S3, S4).

  The invention according to claim 5 is the timing according to the invention according to claim 4, wherein the suspension of the pumping and the reduction of the pumping amount are confirmed by monitoring that the concentration of the purifier has reached a predetermined concentration in the pumping channel portion. It is characterized by being performed by.

  The invention according to claim 6 is the invention according to claim 4, wherein the suspension of the pumping and the reduction of the pumping amount are performed when the pumping amount reaches a predetermined amount or the time for performing the pumping reaches a predetermined time. It is characterized in that it is carried out at a timing when it is confirmed that it has been done.

  Note that the numbers in parentheses are for the sake of convenience indicating the corresponding elements in the drawings, and therefore the present description is not limited to the descriptions on the drawings.

  According to the inventions according to claims 1 to 4, since the infiltration is stopped (or the infiltration rate is reduced) while the purifying agent infiltrates from the injection means to the pumping channel, Purification is promoted.

Fig.1 (a) is a side view which shows an example of a structure of the soil purification system based on this invention, The same figure (b) is the top view. FIGS. 2A to 2D are plan views showing modifications of the arrangement mode of the pumping channel and the like. 3A to 3C are schematic views for explaining the effect of the present invention. FIG. 4 is a flowchart for explaining the soil purification method according to the present invention. FIG. 5 is a schematic diagram (side view) showing an example of a conventional configuration of a soil purification system.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

The soil purification system according to the present invention is for purifying soil in a predetermined area (hereinafter referred to as “purification area”) A1, as illustrated by reference numeral 1 in FIGS. ,
An injection means 2 arranged on one side of the purification area A1 so as to inject a purification agent (nutrient etc.) into the soil (outside the purification area A1);
A pumping path section 3 that is installed in the soil on the other side of the purification area A1 and constitutes a path of groundwater to the ground;
A pumping pump (vacuum pump) 4 connected to the pumping channel 3 and configured to pump groundwater from the pumping channel 3;
The pumping pump 4 is made to permeate (move) the purifier injected into the ground from the injection means 2 into the purification area A1 side (more precisely, the side where the pumping path section 3 is arranged). A pump actuating part 7 to be actuated;
-Stopping the pumping or reducing the pumping amount at the timing when it is determined that the purifying agent has penetrated from the injection means 2 side to the pumping path unit 3 side by a predetermined distance, and stopping the pumping or pumping the pumping A pump control unit 8 for controlling the pump operating unit 7 to resume pumping when a predetermined time has elapsed since the reduction of the amount;
It has. And by pumping up groundwater from the pumping path part 3 by the pumping pump 4, the purification area A1 is traversed from the side where the injection means 2 is arranged to the side where the pumping path part 3 is arranged. It is configured to generate a groundwater flow C. As a result, the purification agent injected from the injection means 2 is diffused and penetrated into the purification area A1 by the groundwater flow C. The pumping pump 4 may be connected to a water treatment facility 6 to purify the pumped groundwater. Here, “one side of the purification area” means a part of the periphery (peripheral part) of the purification area, and “the other side of the purification area” means the above-mentioned part across the purification area. It shall mean the part facing one side. The pump control unit 8 may be configured to stop the pumping or reduce the pumping amount when it is confirmed by monitoring that the concentration of the purifier has reached a predetermined concentration in the pumping channel unit 3. Furthermore, the pump control unit 8 confirms that the amount of pumped water has reached a predetermined amount (that is, a predetermined amount set by a prior investigation, osmotic flow analysis, or the like), or the time for performing pumping reaches a predetermined time. When it is confirmed that it has reached, it is preferable to stop the pumping or reduce the pumping amount.

  According to the present invention, the cleaning agent injected into the soil from the injection means 2 is carried to the purification area A1 by the groundwater flow caused by the pumping channel section 3 and the pumping pump 4, and the purification agent A1 in the area A1. It will penetrate into the soil and the soil will be purified. Further, since the infiltration is stopped (or the infiltration rate is reduced) while the purifying agent penetrates from the injection means 2 to the pumping path portion 3, the soil purification is promoted.

<Pump section>
By the way, the pumping channel portion 3 illustrated in FIG. 1A has a pumping port (well point) 3b in a portion near the tip portion (hereinafter referred to as “tip portion”) 3a and the tip portion 3a is soil. Although it is a pumping pipe arranged in the state embedded in, it is not restricted to this, Of course, It is good also as an excavated pothole (what is called a pumping well). It is preferable that a plurality of the pumping path portions 3 are arranged in parallel along the other side of the purification area A1 (outside the purification area A1). In the case where a plurality of pumping pipes are arranged in parallel, the plurality of pumping pipes and the pumping pump 4 are preferably connected by a pipe member (head pipe) 5.

  Here, when the row B1 formed by juxtaposing the plurality of pumping channel portions 3,... Is referred to as a “pumping channel row”, the pumping channel portion arranged in the vicinity of the end BE of the pumping channel row B1. 3E,... Are arranged closer to the injection means 2 than the pumping path portions 3F,... Disposed in the vicinity of the central portion BF of the pumping path row B1 (that is, on the right side in FIG. 1B). It is good to be made. For example, as illustrated in FIG. 2A, the pumping path row B <b> 2 has an arc shape in which the vicinity of the end BE is close to the injection means 2 and the vicinity of the central portion BF is far from the injection means 2. It is good to do so. Further, as illustrated in FIGS. 7B to 7D, the portion H that is the end H of the purification areas A1 and A2 and is close to the end BE of the pumping channel rows B1, B3, and B4 is a corner. When presenting the section, the pumping path portions 3E,... Arranged in the vicinity of the ends BE of the pumping path rows B1, B3, B4 are preferably arranged along the two sides of the corner portion H. Hereinafter, these arrangement | positioning aspects are demonstrated.

<Arrangement mode (1) of pumping channel>
Now, as illustrated in FIG. 3 (a), when the location 3 to be pumped is one location, the groundwater passing through the injection means 2 will flow to gather at the location 3 (see arrow C1). The purifier does not penetrate into the corner H of the purification area A1, and the soil at the corner H is not purified. In addition, the curve shown with the code | symbol G is an equal water level curve, and has shown that groundwater flows in the direction orthogonal to this equal water level curve. On the other hand, as illustrated in FIG. 5B, when the plurality of pumping channel portions 3,... Are arranged in a line (on a straight line), groundwater flows in a relatively wide area ( The purification agent does not penetrate into the corner portion H of the purification area A1, and the soil at the corner portion H is not purified. On the other hand, as illustrated in FIG. 5C, the pumping passage 3E in the vicinity of the end BE is close to the injection means 2, and the pumping passage 3F in the vicinity of the central portion BF is the injection means 2. When the pumping path row B4 is arranged so as to exhibit an arc shape that is far from the ground, the groundwater flows in a wider area (see arrow C3), and the purifier is at the corner H of the purification area A1. The soil is purified at the corner H.

<Arrangement mode (2) of pumping channel>
On the other hand, an end H of the purification area (see reference signs A1 and A2 in FIGS. 2B to 2D) and a portion H adjacent to the end BE of the pumping path rows B1, B3, and B4 is a corner. Is preferably arranged along the two sides of the corner portion H in the vicinity of the ends BE of the pumping channel rows B1, B3, B4. When the present inventors confirmed by osmotic flow analysis, it turned out that a purification agent penetrate | invades also into the said corner | angular part H from the said some injection | pouring means 2, and the soil purification | cleaning of this corner | angular part H is performed effectively. .

<Interval for installing the pumping channel>
On the other hand, as illustrated in FIG. 2A, the separation distance between the pumping path portions 3F,... In the vicinity of the central portion BF of the pumping path row B2 is the pumping path portion 3E in the vicinity of the end portion BE of the pumping channel row B2. , ... It is good to set it so that it may become smaller than the mutual separation distance. In such a case, even if the distance between the pumping channel portion 3F and the injection means 2 is long, the groundwater flow can be effectively flowed toward the central portion BF of the pumping channel row B2.

<Injection means>
Moreover, as said injection | pouring means 2, the excavated pothole (what is called what is called an injection well) can be mentioned. It is preferable that a plurality of the injection means 2 are arranged in parallel along one side of the purification area A1 (outside the purification area A1).

<Interval for installing injection means>
In the case where a plurality of injection means 2 are arranged side by side, if the water permeability of the soil in the purification area A1,... Is substantially uniform, the injection means 2,. It should be about 4-6m. This is because the permeation range of the purifier injected from the injection means 2 is limited to a radius of about 2 to 3 m at the center of the injection means 2.

  In addition, it is good for the separation distance of the said pumping path part 3 and the said injection | pouring means 2 to be 20-30 m or less.

<Soil purification method>
On the other hand, the soil purification method according to the present invention is a method of purifying the soil in the purification area A1, as illustrated in FIG.
A step S1 of injecting a purification agent into the soil via the injection means 2 arranged on one side of the purification area A1,
-The above-introduced purification agent is obtained by pumping groundwater in the soil through the pumping path part 3 that constitutes the path of groundwater to the ground by being installed in the soil on the other side of the purification area A1. A purification agent permeation step S2 for permeation (diffusion) to the purification area A1 side;
・ Penetration (diffusion) of the purifier by suspending the pumping or reducing the pumping amount at a timing when the purifier is determined to have permeated a predetermined distance from the injection means 2 side to the pumping path portion 3 side. ) To stop or slow down and promote the purification of soil by the penetration of the purification agent, S3, S4,
The soil is purified in the purification area A1 while repeating the purification agent permeation step S2 and the purification promotion steps S3 and S4. According to this method, soil purification is promoted.

Here, the suspension of the pumping and the reduction of the pumping amount may be performed at a timing when it is confirmed by monitoring that the concentration of the purifier has reached a predetermined concentration in the pumping channel section 3. The suspension of the pumping water and the reduction of the pumping amount may be performed at a timing when it is confirmed that the pumping amount reaches a predetermined amount or the time for performing the pumping reaches a predetermined time. Further, in the latter case (that is, the pumping is stopped and the pumping amount is reduced at the timing when it is confirmed that the pumping amount reaches a predetermined amount or the pumping time has reached a predetermined time). )), It is recommended to resume pumping at various timings.

DESCRIPTION OF SYMBOLS 1 Soil purification system 2 Injection means 3 Pumping channel part (pumping pipe)
3a Tip part of pumping pipe 3b Pumping port 4 Pumping pump 7 Pump operation part 8 Pump control part A1 Purification area

Claims (6)

In a soil purification system that purifies the soil in a predetermined area (hereinafter referred to as a “purification area”),
Injection means arranged on one side of the purification area so as to inject the purification agent into the soil;
A pumping path part that is installed in the soil on the other side of the purification area and constitutes a path of groundwater to the ground; and
A pumping pump coupled to the pumping channel and configured to pump groundwater from the pumping channel;
A pump actuating part for actuating the pumping pump so as to infiltrate the purification agent injected into the ground from the injection means into the purification area side;
Pausing the pumping or reducing the pumped amount at the timing when the purifier is judged to have penetrated a predetermined distance from the injection means side to the pumping channel side, and stopping the pumping or reducing the pumped amount A pump control unit that controls the pump operating unit to resume pumping when a predetermined time elapses from,
A soil purification system characterized by comprising: The pump control unit is configured to stop the pumping or reduce the pumping amount at a timing when it is confirmed by monitoring that the concentration of the purifier has reached a predetermined concentration in the pumping channel unit.
The soil purification system of Claim 1 characterized by the above-mentioned. The pump control unit is configured to stop the pumping or reduce the pumping amount when it is confirmed that the pumping amount reaches a predetermined amount and the time for performing the pumping reaches a predetermined time.
The soil purification system of Claim 1 characterized by the above-mentioned. In a soil purification method for purifying soil in a predetermined area (hereinafter referred to as “purification area”),
Injecting a purification agent into the soil through an injection means arranged on one side of the purification area;
A purification agent permeation step for infiltrating the injected purification agent by pumping up groundwater through a pumping path portion that constitutes a path of groundwater to the ground by being installed in the soil on the other side of the purification area; ,
Stopping or slowing the penetration of the purifier by stopping the pumping or reducing the pumping amount at a timing when it is determined that the purifier has permeated a predetermined distance from the injection means side to the pumping channel side. A purification promoting step of promoting the purification of soil by the penetration of the purification agent,
With
Purifying the soil in the purification area while repeating the purification agent permeation step and the purification promotion step,
A soil purification method characterized by that. The suspension of the pumping water and the reduction of the pumping amount are performed at a timing when it is confirmed by monitoring that the concentration of the purifier has reached a predetermined concentration in the pumping channel portion.
The soil purification method of Claim 4 characterized by the above-mentioned. The suspension of the pumping water and the reduction of the pumping amount are performed at the timing when it is confirmed that the amount of the pumping water reaches a predetermined amount, or the time for performing the pumping reaches a predetermined time.
The soil purification method of Claim 4 characterized by the above-mentioned.