JP2015121031A - Mouth pipe for high pressure jet mixing method, and high pressure jet mixing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an agent reach within a wide range in the ground, reduce surplus material's amount of leakage to the non-contaminated ground or ground surface, and shorten a construction period.SOLUTION: A mouth pipe 100 comprises an upper packer 101 and a lower packer 102. The mouth pipe 100's lower part is inserted into a mouth pipe insertion hole obtained by drilling from the ground surface 200 to a predetermined depth (for example, to the contaminated ground). A jet pipe for jetting an agent under high pressure into an agent injection region in the contaminated ground is inserted into the inside of the mouth pipe 100. A lower part packer 102 is arranged at the lower end of the mouth pipe 100, and occludes a gap between the outer peripheral surface of the mouth pipe 100 and the mouth pipe insertion hole by expanding during construction. The upper packer 101 is arranged at the upper end of the mouth pipe 100, and occludes a gap between the outer peripheral surface of the jet pipe and the inner peripheral surface of the mouth pipe 100 by expanding during the construction.

Description

  The present invention relates to a mouth tube for a high-pressure jet agitation method and a high-pressure jet agitation method for injecting a chemical into the ground in an in-situ purification of contaminated soil.

Measures aimed at removing soil contamination include excavation and removal of soil contaminated with specific hazardous substances and backfilling with uncontaminated soil, and moving contaminated soil from the site (original location) In-situ purification that removes specific harmful substances.
In excavation and removal, there are concerns about secondary environmental pollution due to the movement of contaminated soil, and soaring costs for disposal of contaminated soil due to tightness of the recipient of the contaminated soil (treatment plant). Yes.

Recently, there are many examples of “in-situ decomposition” among in-situ purification methods. This is a method of decomposing specific harmful substances in situ by chemical or biological action. In other words, on site, an oxidizing agent or a reducing agent is added to contaminated soil to cause a chemical decomposition reaction of specific harmful substances, or a nutrient is added to increase the activity of soil microorganisms and promote the decomposition of specific harmful substances. It is a technique. In order to add these chemicals to the contaminated soil at a reduced cost, there is a need for a method that can efficiently inject the drug from the ground into the target contaminated area without moving the contaminated soil as much as possible.
However, until now, it has been difficult to effectively purify contaminated soil by in-situ decomposition using a chemical injection method because the chemicals do not penetrate into the ground in the poorly permeable ground such as viscous soil layer and silt layer. It was.

  On the other hand, one of the injection methods for the purpose of ground improvement in civil engineering work is the high-pressure jet agitation method. This method can improve the poorly permeable ground. However, in this construction method, it may be necessary to quickly discharge the generated surplus (slime) to the ground surface in order to create a high-quality improved body. For this reason, when such a conventional high-pressure jet agitation method is carried out in the in-situ soil purification work, contaminated surplus materials are discharged to the ground surface, and there is a possibility that specific harmful substances are diffused.

Therefore, in order to reduce the discharge amount of surplus materials to the surface, it is conceivable to apply the techniques described in Patent Document 1 and Patent Document 2, for example.
Patent Document 1 discloses a mouth pipe that can adjust the discharge amount of surplus and can further smooth the discharge outside the mine. This mouth tube is used in the horizontal high-pressure injection injection method.
In Patent Document 2, a borehole is drilled to a hardly permeable ground including a contaminated region, a cut is formed on the inner wall surface of the borehole in the hardly permeable ground, and packers are arranged above and below the region where the cut is formed. Then, a contaminated soil purification method is disclosed in which the chemical is supplied to the region sandwiched between these packers while being pressurized. According to this construction method, when the chemical is pressurized and supplied, splitting progresses from the notch formed in the inner wall surface of the borehole into the poorly permeable ground, so that the chemical reaches a relatively wide range through the advanced splitting. Can be made. Furthermore, the amount of the drug leaking to the upper and lower soil layers and the ground surface that are not contaminated can be reduced by the upper and lower packers.

JP-A-5-280275 JP 2010-179219 A

However, even if the mouth tube described in Patent Document 1 is used, a large amount of surplus material is discharged to the ground surface. Moreover, the reach | attainment range of the chemical | medical agent in the ground cannot be expanded only by using this mouth pipe | tube.
The contaminated soil remediation method described in Patent Document 2 can cause the chemical to reach a relatively wide area in the ground and reduce the leakage of surplus materials to the non-polluted ground and the ground surface. It may take a long time to progress further.

  The object of the present invention is to achieve a high-pressure jet agitation method that can reach a wide area in the ground, reduce the amount of excess material leaking to the non-contaminated ground and the ground, and shorten the construction period. It is to provide a mouth tube and a high-pressure jet stirring method.

In order to achieve the above object, the mouth tube for the high-pressure jet stirring method of the present invention is
A high-pressure jet agitation method mouth tube into which an injection tube for injecting a drug from the tip is inserted,
It is arranged at one end of the high-pressure jet agitation method mouth pipe, and when expanded, an outer peripheral surface of the high-pressure jet agitation method mouth pipe and a mouth tube insertion hole into which the high-pressure jet agitation method mouth pipe is inserted A lower packer that closes the first gap between,
The upper part which is arrange | positioned at the other end of the said high pressure injection stirring method mouth pipe, and if it expand | swells, obstruct | occludes the 2nd clearance gap between the outer peripheral surface of the said injection pipe and the inner peripheral surface of the said high pressure injection stirring method mouth pipe With packer,
It is characterized by providing.

Preferably, the mouth pipe for the high-pressure jet stirring method of the present invention is
A pressure gauge is provided for measuring the pressure of the surplus material that enters the gap between the inner peripheral surface of the high-pressure jet agitation method mouth pipe and the outer peripheral surface of the spray pipe.

Moreover, the high-pressure jet stirring method of the present invention is
It is a high-pressure jet stirring method using the above-mentioned high-pressure jet stirring method mouth pipe,
A mouth tube insertion hole drilling step for drilling the mouth tube insertion hole from the ground surface to a predetermined depth;
Inserting and installing the high-pressure jet agitation method mouth tube into the drilled mouth tube insertion hole, inflating the lower packer to close the first gap, the mouth tube installation step,
An injection tube insertion hole drilling step for drilling an injection tube insertion hole from the bottom of the mouth tube insertion hole to the lowest part of the drug injection region;
An injection pipe that is installed by inserting the injection pipe into a cavity inside the mouth pipe for the high-pressure injection agitation method and the drilled injection pipe insertion hole, and inflating the upper packer to close the second gap. Installation process;
A medicine injection step of injecting medicine from the injection pipe until the tip of the injection pipe reaches the top of the region where medicine injection is scheduled, and pulling up the injection pipe at a constant speed while rotating at a constant speed; ,
A pressure process in which the pressure is monitored by the pressure gauge, and when the pressure falls below a predetermined value, the medicine is injected at a high pressure from the tip of the injection tube, and the pressure in the region where the medicine is injected is recovered and maintained at the predetermined pressure; ,
It is characterized by providing.

  ADVANTAGE OF THE INVENTION According to this invention, a chemical | medical agent can be made to reach | attain in the wide range in the ground, the leakage amount of the surplus thing to the non-contaminated ground and the ground surface can be reduced, and a construction period can be shortened.

It is a longitudinal cross-sectional view which shows an example of the structure of the mouth tube used with the high pressure injection stirring method which concerns on embodiment of this invention. It is a figure which shows the injection | pouring principle of the high pressure injection stirring method which concerns on embodiment of this invention. It is a figure which shows an example of the flow of the process of the high pressure injection stirring method which concerns on embodiment of this invention. It is a figure which shows an example of a mouth pipe insertion hole drilling process. It is a figure which shows an example of a mouth pipe | tube insertion process. It is a figure which shows an example of an injection pipe insertion hole drilling process. It is a figure which shows an example of an injection pipe insertion process. It is a figure which shows an example of the state immediately after the start of a chemical | medical agent injection | pouring process. It is a figure which shows an example of the state of the intermediate | middle stage of a chemical | medical agent injection | pouring process. It is a figure which shows an example of the state which the front-end | tip between injection reached the uppermost part of the chemical | medical agent injection | pouring area | region in the chemical | medical agent injection | pouring process. In a pressurization process, it is a figure which shows an example of the state which the pressure of the chemical | medical agent injection | pouring area | region obstruct | occluded by the upper packer and the lower packer rose, and the chemical | medical agent injection area | region expanded.

  Hereinafter, a high-pressure jet stirring method mouth pipe and a high-pressure jet stirring method according to an embodiment of the present invention will be described with reference to the drawings. In all the drawings for explaining the embodiments, common constituent elements are denoted by the same reference numerals, and repeated explanation is omitted.

FIG. 1 shows an example of a configuration of a mouth tube 100 used in a high-pressure jet stirring method according to an embodiment of the present invention.
The mouth tube 100 includes an upper packer 101, a lower packer 102, and a pressure gauge 103. The lower part of the mouth pipe 100 is inserted into the mouth pipe insertion hole that has been drilled from the ground surface 200 to a predetermined depth (for example, until reaching the contaminated ground). Further, the mouth tube 100 has a cavity into which the drilling tube and the injection tube are inserted. Here, the drilling tube is a tube for drilling the injection tube insertion hole from the bottom of the mouth tube insertion hole to the bottom of the region where the drug is injected (hereinafter referred to as the drug injection region). This is a tube for injecting a drug at a high pressure into the drug injection region. The mouth tube 100 is an example of a mouth tube for a high-pressure jet stirring method.
The lower packer 102 is disposed at the lower end of the mouth tube 100. The lower packer 102 expands during construction and closes the gap between the outer peripheral surface of the mouth tube 100 and the mouth tube insertion hole. The upper packer 101 is disposed at the upper end portion of the mouth tube 100. The upper packer 101 expands during construction and closes the gap between the outer peripheral surface of the injection tube and the inner peripheral surface of the mouth tube 100. The material of the upper packer 101 and the lower packer 102 is, for example, rubber. The upper packer 101 and the lower packer 102 are inflated by water pressure, air pressure, mechanical compression force, or the like at the time of construction, and are restored to their original shapes by releasing the water pressure, air pressure, mechanical compression force, or the like after the work is completed.
The pressure gauge 103 measures the pressure of the surplus material that enters the gap between the inner peripheral surface of the mouth tube 100 and the outer peripheral surface of the injection tube. Since this gap is connected to the drug injection region, the pressure in the drug injection region can be indirectly measured by the pressure gauge 103.

FIG. 2 shows the injection principle of the high-pressure jet stirring method according to the embodiment of the present invention.
At the time of construction, the injection pipe 120 is inserted into the mouth pipe 100. At this time, the tip of the injection tube 120 reaches the lowest part of the drug injection region. Then, the lower packer 102 and the upper packer 101 are inflated, and the gap between the outer peripheral surface of the mouth tube 100 and the mouth tube insertion hole, and the gap between the outer peripheral surface of the injection tube and the inner peripheral surface of the mouth tube 100, respectively. Occlude.
Then, the injection tube 120 is pulled up while rotating the injection tube 120 while spraying the drug at an ultra-high pressure in a direction perpendicular to the axis of the injection tube 120 from the injection hole of the nozzle installed at the tip of the injection tube 120. As a result, the drug and the soil are mixed and stirred, and a disk-shaped split 300 is generated in the soil. The drug spreads over a wide area through the disc-shaped split 300.

FIG. 3 shows an example of a process flow of the high-pressure jet stirring method according to the embodiment of the present invention.
The high-pressure injection agitation method includes a mouth tube insertion hole drilling step (S1), a mouth tube installation step (S2), a spray tube insertion hole drilling step (S3), a spray tube installation step (S4), and a chemical injection. It consists of a process (S5) and a pressurization process (S6).
In the mouth tube insertion hole drilling process of step S1, as shown in FIG. 4, a predetermined depth (for example, uncontaminated uncontaminated ground 210 and contaminated contaminated ground 220 is removed from the ground surface 200 by a boring machine or the like. The mouth tube insertion hole 211 is drilled up to the vicinity of the boundary).
Next, in the mouth tube installation step of step S2, the mouth tube 100 is inserted and installed in the mouth tube insertion hole 211 as shown in FIG. Then, the lower packer 102 is inflated to close the gap between the outer peripheral surface of the mouth tube 100 and the mouth tube insertion hole 211.
Next, in the injection tube insertion hole drilling step of step S3, as shown in FIG. 6, the drilling tube 110 is inserted into the mouth tube 100, and the planned depth (in the drug injection region) is measured from the bottom of the mouth tube insertion hole 211. The injection tube insertion hole 221 is drilled up to the lowermost part.
Next, in the injection tube installation step of step S4, as shown in FIG. 7, the drilling tube 110 is pulled out, and the injection tube 120 is inserted and installed in the cavity inside the mouth tube 100 and the injection tube insertion hole 221. Then, the upper packer 101 is inflated to close the gap between the outer peripheral surface of the injection tube 120 and the inner peripheral surface of the mouth tube 100. 7 to 11, the gap between the outer peripheral surface of the injection pipe 120 and the contaminated ground 220 is drawn with emphasis, but actually, the outer peripheral surface of the injection pipe 120 and the contaminated ground 220 are in close contact with each other. Yes.

Next, in the medicine injection process in step S5, as shown in FIGS. 8 to 10, the medicine 130 is injected at a high pressure in a direction perpendicular to the axis of the injection pipe 120 from the injection hole of the nozzle installed at the tip of the injection pipe 120. Spray. The injection pressure of the medicine 130 is preferably in the range of P = 20 to 40 MPa (Pascal). The injection amount of the medicine 130 is desirably in the range of Q = 80 to 200 liters / minute. The injection pipe 120 is desirably pulled up at a constant speed while rotating at a constant speed.
As shown in FIG. 8, when a medicine is injected at a high pressure, the medicine and soil are mixed and stirred, and a disc-shaped split 300 is generated in the soil. At this time, surplus (slime) 230 rises in the gap between the outer peripheral surface of the injection pipe 120 and the contaminated ground 220 and reaches the bottom of the mouth pipe insertion hole 211. However, since the gap between the outer peripheral surface of the mouth tube 100 and the mouth tube insertion hole 211 is closed by the lower packer 102, the surplus material 230 is prevented from entering the gap.
If the medicine is continuously injected at a high pressure while pulling up the injection tube 120, as shown in FIG. 9, the surplus 230 increases the gap between the outer peripheral surface of the injection tube 120 and the inner peripheral surface of the mouth tube 100, Although reaching the upper packer 101, leakage of the surplus material 230 to the ground surface is prevented by the upper packer 101. Thereafter, the pressure of the surplus material 230 that has entered the gap between the inner peripheral surface of the mouth tube 100 and the outer peripheral surface of the injection tube can be measured by the pressure gauge 103.
As shown in FIG. 10, when the tip of the injection tube 120 reaches the top of the region where the medicine injection is scheduled, the lifting of the injection tube 120 is stopped.

In the pressurization process of step S6 shown in FIG. 11, the pressure is monitored by the pressure gauge 103, and when the pressure falls below a predetermined value, the medicine 130 is injected at a high pressure from the injection hole of the nozzle installed at the tip of the injection pipe 120. . Thereby, the pressure in the medicine injection region is recovered and maintained at a predetermined pressure. At this time, the raising of the injection pipe 120 is in a stopped state. The injection pipe 120 may or may not be rotated.
In the pressurization step, the surplus 230 is blocked in the ground and the pressure in the drug injection region is increased, so that the drug 130 is expanded in the soil and the expanded region 310 is wider than the region where the disc-shaped split 300 is generated. To spread.

(Example)
A CCP-S (Chemical Charging Pile-Super) method, which is a general high-pressure jet agitation method, and a high-pressure jet agitation method (hereinafter referred to as this method) according to the present embodiment, a purifier (chemical) into the soil. An injection test was conducted and the reach of the cleaner in the soil was examined. In both methods, the construction was carried out at an injection pressure P = 40 MPa (Pascal) and an injection amount Q = 100 liters / minute.
The reach of the purifier was determined on the basis of changes in electrical conductivity before and after construction at each position 0.5 m, 1.0 m, and 1.5 m away from the construction position. The electrical conductivity was measured to a depth of 12 m with an EC (electrical conductivity) probe attached to a small self-propelled boring machine, penetrating into the soil.
It is known that the electrical conductivity detected by the EC probe shows different values mainly depending on the water content and electrolytic mass of each soil. The electrical conductivity of each soil before construction of the test site of the example is as follows: sandy soil: 10-30 mS / m, sandy silt: 30-50 mS / m, silt: 40-60 mS / m, soft mudstone: 50- It showed a distribution of 70 mS / m (in order of water content in the natural state).
The bioremediation purification agent tested contained saccharides, amino acids, sodium ions, and the like as electrolytes, and the electrical conductivity of the purification agent itself showed a value of about 300 mS / m. Therefore, when a nutrient reaches, it becomes higher than the electrical conductivity of each soil before construction. As a result of measuring the electrical conductivity at a position 1.5 m away from the construction position with the EC probe after construction, it showed a larger value than the electrical conductivity before construction, and confirmed that the drug had reached.

  The following table shows a comparison of the reach of purifiers by both methods. From this table, it can be seen that the purifier reached a range of 1.15 to 1.36 times that of the CCP-S method by this method.

  In the above-described embodiment, the hole-drilling pipe 110 and the injection pipe 120 are different pipes, but these can be combined with one pipe.

Moreover, all the chemical | medical agents which can be inject | poured into the soil relevant to soil contamination countermeasures / measures can be the object of the high-pressure jet stirring method according to the present invention. Examples of drugs are listed below.
(1) Bioremediation (Biostimulation)
Nutrients that promote the activity of soil microorganisms (water-soluble nutrients, nutrients emulsified with vegetable oil, etc., and nutrients that finally become liquid with solvents such as water, regardless of powder or solid).
(2) Bioremediation (bioaugmentation)
A liquid mixture of cells and nutrient medium in which microorganisms (groups) that are effective in decomposing specific harmful substances are cultured outside.
(3) Oxidizing agents (hydrogen peroxide, persulfates, permanganic acid, etc.) used in chemical oxidation treatment methods and their catalysts (eg ferrous sulfate)
(4) Iron powder used in the reductive decomposition method (preferably having a slurry particle size of micron order)
(5) Although not in the category of in-situ purification, insolubilizers for "in-situ insolubilization" (those that insolubilize Specified Hazardous Substances such as calcium oxide and magnesium oxide (heavy metals, etc.) in the soil)

As described above, according to the present invention, it is possible to reduce the amount of excess material leaking to the non-contaminated ground or the ground surface.
Further, according to the present invention, since the surplus is blocked in the ground and the pressure in the region where the drug is injected is increased, the drug is spread in the soil and spreads over a wide range.
Furthermore, according to the present invention, a disk-shaped split is generated in the soil by the rotation of the injection tube, and the drug spreads through the split, so that the drug spreads over a wide range in a short time.
Further, according to the present invention, the pressure of the surplus material entering the gap between the inner peripheral surface of the mouth tube and the outer peripheral surface of the injection tube (that is, the drug injection region in the soil) by the pressure gauge attached to the mouth tube Can be measured.

  Although the embodiments of the present invention have been described above, various modifications and combinations necessary for design reasons and other factors are described in the inventions described in the claims and the specific embodiments described in the embodiments of the invention. It is included in the scope of the invention corresponding to the example.

DESCRIPTION OF SYMBOLS 100 ... Mouth pipe, 101 ... Upper packer, 102 ... Lower packer, 103 ... Pressure gauge, 110 ... Drilling pipe, 120 ... Injection pipe, 130 ... Drug, 200 ... Ground, 210 ... Non-contaminated ground, 211 ... Mouth pipe Hole 220, contaminated ground, 221 ... injection tube insertion hole, 230 ... surplus (slime), 300 ... disk-shaped split, 310 ... enlarged region

Claims (3)

A high-pressure jet agitation method mouth tube into which an injection tube for injecting a drug from the tip is inserted,
It is arranged at one end of the high-pressure jet agitation method mouth pipe, and when expanded, an outer peripheral surface of the high-pressure jet agitation method mouth pipe and a mouth tube insertion hole into which the high-pressure jet agitation method mouth pipe is inserted A lower packer that closes the first gap between,
The upper part which is arrange | positioned at the other end of the said high pressure injection stirring method mouth pipe, and if it expand | swells, obstruct | occludes the 2nd clearance gap between the outer peripheral surface of the said injection pipe and the inner peripheral surface of the said high pressure injection stirring method mouth pipe With packer,
A mouth tube for a high-pressure jet agitation method characterized by comprising:   The high-pressure injection according to claim 1, further comprising a pressure gauge for measuring a pressure of surplus material that enters a gap between an inner peripheral surface of the high-pressure jet agitation method mouth pipe and an outer peripheral surface of the injection pipe. Mouth pipe for stirring method. A high-pressure jet stirring method using the high-pressure jet stirring method mouth pipe according to claim 2,
A mouth tube insertion hole drilling step for drilling the mouth tube insertion hole from the ground surface to a predetermined depth;
Inserting and installing the high-pressure jet agitation method mouth tube into the drilled mouth tube insertion hole, inflating the lower packer to close the first gap, the mouth tube installation step,
An injection tube insertion hole drilling step for drilling an injection tube insertion hole from the bottom of the mouth tube insertion hole to the lowest part of the drug injection region;
An injection pipe that is installed by inserting the injection pipe into a cavity inside the mouth pipe for the high-pressure injection agitation method and the drilled injection pipe insertion hole, and inflating the upper packer to close the second gap. Installation process;
A medicine injection step of injecting medicine from the injection pipe until the tip of the injection pipe reaches the top of the region where medicine injection is scheduled, and pulling up the injection pipe at a constant speed while rotating at a constant speed; ,
A pressure process in which the pressure is monitored by the pressure gauge, and when the pressure falls below a predetermined value, the medicine is injected at a high pressure from the tip of the injection tube, and the pressure in the region where the medicine is injected is recovered and maintained at the predetermined pressure; ,
A high-pressure jet stirring method characterized by comprising:

Images