JP2008058060A - Contaminant concentration measuring technique - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contaminant concentration measuring technique capable of measuring the contaminant concentration similar to the actual situation of contaminated soil, in consideration of even existence of a contaminant unseparated from soil particles. <P>SOLUTION: When pulling up a jetting/injection device 20, jets (for example, crossing jets) comprising high-temperature fluid are jetted from nozzles 221, 222 provided on the jetting/injection device 20, and each jet Jc from a pair of nozzles collides with each other at a crossing point Pjc on the outward in the radial direction. Hereby, the contaminant is separated from soil particles by kinetic energy and heat energy carried by the jets Jc comprising the high-temperature fluid, and the concentration of the contaminant included in slime and/or gas springing out onto the ground side is measured. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for measuring the concentration of a pollutant in soil contaminated with a pollutant such as an organic solvent or other volatile substances (VOC) or heavy metals.

In connection with the recent increase in recognition of soil contamination, various technologies for removing contaminants in soil, that is, contaminated soil purification technologies, have been proposed.
As a conventional contaminated soil purification technology, for example, a technique is known in which soil in a contaminated basin is collected and subjected to a laboratory test for water purification, and the change in contamination concentration over time is simulated three-dimensionally based on the data. (See Patent Document 1).

Here, the concentration of the pollutant is generally measured by collecting soil in the contaminated area as a sample and subjecting the sample to physical treatment and chemical treatment.
However, since the soil particles themselves have a lattice-like structure, when contaminants such as VOC are incorporated into the lattice, the incorporated contaminants move outside the lattice structure. It is hard to do. For example, when the soil is clay, the clay particles have an electric charge, and the electric charges adsorb contaminants such as VOC by the electric charge. Of course, the contaminants are adsorbed on the surface of the soil particles other than clay by an action other than the electric adsorption force.
In both cases where the contaminant is taken into the lattice of the soil particles and where the contaminant is adsorbed on the surface of the soil particles, the contaminant is unlikely to be separated from the soil particles. And if the physical process and the chemical process which are performed in a prior art are given, a contaminant will be hard to isolate | separate from a soil particle.

In many cases, it is difficult to detect the pollutant unless it is separated from the soil particles. Therefore, in the prior art, the pollutant concentration is measured based on the pollutant eluted from the soil into the water.
In other words, the contaminants that are not separated from the soil particles and are not eluted in the water are difficult to detect by the prior art, and considering the presence of the contaminants that are not separated from the soil particles, Contaminant concentration close to the actual condition of contaminated soil could not be measured.
JP 2006-116509 A

  The present invention has been proposed in view of the above-mentioned problems of the prior art, and the concentration of contaminants close to the actual condition of contaminated soil is measured in consideration of the presence of contaminants that are not separated from soil particles. The purpose is to provide a pollutant concentration measurement method that can be used.

  As a result of various studies, the inventors have found that even pollutants that are electrically adsorbed with soil particles or taken into the lattice-like structure of soil particles and are difficult to elute to the outside are heated at high temperatures. It has been found that by colliding with a jet of energy, it separates or separates from the soil particles.

  The pollutant concentration measurement method of the present invention was created based on such knowledge, and excavates (boring hole H) to an area in the ground where the concentration of pollutants (heavy metal, volatile substances, etc.) should be measured. The injection and injection device (monitor 20) is inserted in the insertion step, the injection and injection device (monitor 20) is lifted up, and the slime and / or gas that flows out to the ground side during the lifting step is included. And a concentration measuring step for measuring the concentration of the pollutant, and in the pulling step, the nozzle (221, 222) provided above the injection and injection device (monitor 20) is heated to a high temperature (for example, 80 ° C to 90 ° C). ) Fluid (e.g., water or water vapor) (Jc: e.g., so-called "cross jet") from an injection port (21o) provided below the injection and injection device (monitor 20) Filling material (C) is injected, and pollutants are separated from soil particles by kinetic energy and thermal energy held by a jet (Jc) composed of a fluid at a high temperature (for example, 80 ° C. to 90 ° C.). (Claim 1).

In the pollutant concentration measuring method of the present invention, the pollutant separated from the soil particles in the lifting step elutes in the slime and floats to the ground side together with the slime, and the pollutant concentration is measured by collecting the slime on the ground side. (Claim 2).
Alternatively, in the pollutant concentration measuring method of the present invention, the pollutant separated from the soil particles in the lifting step floats to the ground side together with the air jetted together with the jet, and collects the gas floating on the ground side to collect the pollutant concentration Is preferably measured (Claim 3).

  In the present invention, in the concentration measuring step, the concentration of the pollutant separated from the soil particles in the pulling step can be measured by the pollutant concentration measuring means (310) disposed in the ground (claim 4). ).

  In carrying out the present invention, it is carried out simultaneously with a contaminated soil purification method for purifying contaminated soil, the contaminated soil purification method comprising a step of drilling a borehole and inserting an injection and injection device, and an injection and injection device When rotating the nozzle, a cross jet composed of high-temperature (for example, 80 ° C. to 90 ° C.) water is injected from at least a pair of nozzles provided above the injection and injection device, and provided below the injection and injection device. And a step of injecting the filling material from the injection port.

  More preferably, the contaminated soil remediation method includes a step of removing contaminants by a purification facility provided on the ground side when slime that has flowed to the ground side when injecting a cross jet and injecting a filling material, and removing the contaminants. And supplying the applied slime to the injection and injection device.

According to the pollutant concentration measuring method of the present invention having the above-described configuration, a jet of a high-temperature fluid (for example, a so-called “cross jet”) is jetted from a nozzle provided above the jetting and injecting device. The soil is composed of high-temperature (for example, 80 ° C. to 90 ° C.) water, and is finely crushed by a jet having a large amount of kinetic energy.
As a result, contaminants such as VOC attached to the soil are separated or separated from the soil particles when the soil is finely crushed by the synergistic action of the heat and kinetic energy of the jet.
The contaminants separated or separated from the soil particles are in a state of being eluted in the slime, or in a state of being mixed with the air jetted together with the cross jet in the gas phase.
The slime from which the pollutant is eluted and / or the gas mixed with the gas phase pollutant flows out to the ground side through the borehole. In other words, the contaminant is entrained in the slime or gas and moves from the original position to the ground side.

For example, when the soil is clay, the clay particles have an electric charge, and the contaminants such as VOC are electrically adsorbed by the electric charge. Alternatively, the soil particles themselves have a lattice-like structure, and contaminants such as VOC are taken into the lattice and are hardly eluted to the outside.
However, in the present invention, when the clay particles are shredded by a high-temperature and high-energy jet, the contaminants electrically adsorbed on the clay particles are separated from the clay particles. Alternatively, the lattice-like structure of the soil particles is destroyed by a high-temperature and high-energy jet, and the contaminants trapped inside the lattice are easily eluted.

That is, according to the present invention, the contaminant contained in the clay, which has been difficult to remove by the prior art, is also peeled off from the clay, removed, and eluted in the slime, and / or in the gas phase. Become mixed with the injected air.
In the state of elution in the slime, contaminants are easily and reliably removed from the slime by aeration, electrophoresis or other various means. Therefore, it is easier to remove the contaminants eluted in the slime than the contaminants attached to the contaminated soil.
Similarly, gas phase contaminants can be easily removed by suction with a blower or other suction means.

According to experiments by the inventors, the pollutant concentration measured in the present invention is twice to several tens of times as compared to measuring the concentration of pollutants eluted in water by the conventional pollutant concentration measuring method. It has been found that it is about twice as high. This fact is presumed to be due to the following reasons.
In the conventional pollutant concentration measuring method, pollutants such as VOC that are taken into the soil particles of the contaminated soil or adsorbed on the surface of the soil particles are difficult to separate from the soil particles. For this reason, in the prior art, contaminants such as VOC that are taken into or electrically adsorbed into the soil particles of the contaminated soil are difficult to elute into water, and the actual content cannot be detected by a measuring instrument. Met.
On the other hand, according to the present invention, the lattice structure of the soil particles is destroyed by the jet of high temperature and high energy, and the clay particles and the electrically adsorbed contaminants are separated or separated. Contaminants that could not be detected become measurable. Therefore, the measurement result by this invention can show the substance of contaminated soil more correctly compared with the conventional measuring method.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
First, with reference to FIGS. 1-4, 1st Embodiment of the contaminant concentration measuring method of this invention is described.
In FIG. 1, a measuring system for carrying out the pollutant concentration measuring method includes a construction machine 101, an excavator 1, a slime storage tank 4, and a VOC concentration analyzer 104 (for example, “gas chromatograph— And an analysis apparatus 106 using a photoionization detection method (GC-PID) ”and a VOC concentration analysis apparatus 106 in the slime.

1 and 2 show a state in which a triple pipe rod 2 (described later) of the excavator 1 is inserted into a drilled hole H and a pollutant concentration measuring method is being applied.
In FIG. 1 and FIG. 2, symbol G indicates soil in general, and symbol Gp indicates contaminated soil or a contaminated area.

In particular, as shown in detail in FIG. 2, the excavator 1 includes a triple pipe rod 2. The triple tube rod 2 is configured such that the first tube 21, the second tube 22, and the third tube 23 are concentric. The 1st pipe | tube 21 is arrange | positioned radially innermost, and the 3rd pipe | tube 23 is arrange | positioned radially outermost.
1 and 2, a casing pipe CP is inserted into the bore hole H.

The filling material C is supplied into the first pipe 21. A filling material injection port 21o is formed near the tip of the first tube 21 (the lower end in FIG. 2).
As the filling material C, not only a normal solidified material but also purified slime can be used again as described in a second embodiment to be described later. Further, the purified slime can be reintroduced as a cutting fluid.

Nozzles 221 and 222 are provided in the second tube 22 and the third tube 23. The nozzles 221 and 222 are spaced apart in the vertical direction and are provided in pairs. Jet jets J1 and J2 ejected from the pair of nozzles 221 and 222 collide at a predetermined position Pjc (intersection) to form a so-called “cross jet” Jc.
Here, the casing pipe CP is disposed so as not to interfere with the cross jet Jc.
In FIG. 2, only a pair of nozzles 221 and 222 for injecting the cross jet Jc is shown, but a plurality of pairs of nozzles for injecting the cross jet Jc can be provided.

The jet jets J1 and J2 are preferably composed of high-pressure water having an ultrahigh pressure. And it is preferable that the temperature of high temperature water is the temperature which the water which is cutting fluid does not boil, for example, 80-90 degreeC.
In the triple tube rod 2 of FIG. 2, the devices in the region from the nozzles 221 and 222 to the filling material injection port 21o constitute a filling monitor 20 (injection and injection device).

In FIG. 2, the high temperature water jets J1 and J2 are surrounded by a jet Ja of high temperature compressed air. Although not shown in detail, the nozzles 221 and 222 are concentrically arranged, and the radially inner side communicates with the annular space between the first tube 21 and the second tube 22, and from the radially inner side. Hot water jets J1 and J2 are jetted. The outer sides in the radial direction of the nozzles 221 and 222 communicate with the annular space of the second pipe 22 and the third pipe 23, and the hot compressed air jet Ja is injected from the outer side in the radial direction.
The temperature of the jet Ja of compressed air is a temperature that does not vaporize the water constituting the jets J1 and J2. However, the compressed air jet Ja can be omitted.
Further, in the above-described content, in the triple tube rod 2, the filling material C flows through the first tube 21, the high-pressure hot water flows through the annular space between the first tube 21 and the second tube 22, and the high temperature The compressed air flows through the annular space between the second tube 22 and the third tube 23, but is not limited thereto. For example, the filling material C is supplied through the annular space of the second pipe 22 and the third pipe 23, the high-pressure hot water flows through the first pipe 21, and the high-temperature compressed air flows between the first pipe 21 and the second pipe 21. You may comprise so that it may be supplied through the annular space of this pipe | tube 22.

In FIG. 1, a triple tube swivel 9 is attached to the end of the triple tube rod 2 on the ground E side.
Although not shown, the triple tube swivel 9 is provided with a filling material supply port, an ultrahigh pressure water supply port, and a compressed air supply port. The first pipe 21 communicates with a filling material supply port (not shown). An annular space between the first pipe and the second pipe 22 communicates with an ultrahigh pressure water supply port (not shown). And the annular space between the 2nd pipe | tube 22 and the 3rd pipe | tube 23 is connected to the compressed air supply port which is not shown in figure.

In FIG. 2, the triple tube rod 2 is covered with a mouth tube 3 in the vicinity of the ground surface Ef. A connection port 3 o is formed on the outer periphery of the mouth tube 3. Although not clearly shown, the connection port 3o communicates with the annular space K between the third pipe 23 and the casing pipe CP.
An annular space K between the third pipe 23 and the casing pipe CP serves as a discharge passage through which slime and / or gas floats to the ground side. In FIG. 2, an arrow S in the annular flow path K indicates the direction of the slime and / or gas flow.
One end T1a of the first slime transport pipe T1 is connected to the connection port 3o.

A cover 3 </ b> C is installed on the basement side of the mouth pipe 3.
In the unlikely event that a slime or gas containing harmful substances leaks from the mouth pipe 3, the leaked slime and / or gas will scatter and permeate the ground surface or underground, or pollute the surrounding environment. In order to prevent this, a cover 3C is provided.
The mouth tube 3 and the cover 3C are connected by a known means such as a flange.

In FIG. 1, the end portion T <b> 1 b on the side separated from the mouth tube 3 of the first slime transport pipe T <b> 1 opens from the upper side to the lower side in the slime storage tank 4.
1 and 2, a slime sample extraction device 10 is interposed in the vicinity of the mouth tube 3 in the first slime transport tube T1.

The slime sample extraction device 10 extracts a part of the slime discharged from the construction area to the ground side as a sample.
The extracted sample is sent to the VOC concentration analyzer 106 in the slime manually or by a conveyance line or the like (shown by a one-dot chain line denoted by Lc1 in FIG. 1). The VOC concentration analyzer 106 in the slime is a conventionally known analyzer.
The VOC concentration analyzer 106 in the slime performs physical treatments and chemical treatments necessary for analysis, and then measures various contaminant concentrations contained in the slime.

In addition to the slime sample extraction device 10, the slime storage tank 4 is provided with a gas sampling device 108. The gas sampling device 108 is located near the end T1b of the first slime transport pipe T1.
The contaminants are eluted in the slime, but are mixed with the air of the compressed air jet Ja and come out to the ground side. The air constituting the compressed air jet Ja is discharged from the first slime transport pipe T1, but vaporized contaminants, for example, contaminants such as gas phase VOCs are intermittently ejected.
The gas sampling device 108 is connected to the line Lc2, and a suction device (not shown in FIG. 1) such as a blower is interposed in the line Lc2. A gas phase pollutant is sucked by a suction device (not shown), and a gas (mixed gas of gas phase pollutant and air) collected via the line Lc2 is sent to the VOC concentration analyzer 104 in the gas as the analyzer. Send and measure pollutant concentration in real time.

In the embodiment shown in FIGS. 1 and 2, the cutting fluid or the filling material C may contain a chemical (for example, a reducing agent, an oxidizing agent, etc.). Alternatively, the cutting fluid constituting the cross jet Jc may contain microorganisms, microorganism nutrients, a VOC decomposer using microorganisms (for example, a VOC decomposer commercially available under the trade name “HRC”), and the like. .
This is because, by adding such a chemical or the like to the cutting fluid or the filling material C, the construction efficiency is improved when construction is performed in combination with the contaminated soil purification method in the second embodiment to be described later.

The construction procedure of the pollutant concentration measuring method according to the embodiment shown in FIGS. 1 and 2 will be described with reference mainly to FIG.
In measuring the pollutant concentration, first, a boring hole H (FIG. 1) is excavated to a region in the soil where the concentration of the pollutant (for example, VOC) is to be measured (step S1 in FIG. 3). Then, the triple tube rod 2 is inserted into the boring hole H (step S2).
As described above with reference to FIGS. 1 and 2, the triple tube rod 2 is provided with a pair of nozzles 221 and 222 for injecting the cross jet Jc and a filling material injection port 21 o for injecting the filling material C. Yes.

When the inserted triple tube rod 2 reaches the region where the concentration of contaminants should be measured (the state shown in FIGS. 1 and 2), a cross jet Jc is jetted from a pair of nozzles 221 and 222, and a filling material injection is performed. Filling material C is injected from the inlet 21o (step S3).
In step S3, the clay particles are shredded by the high-temperature, high-energy cross jet Jc, so that the contaminants electrically adsorbed on the clay particles and the various contaminants adsorbed on the surface of the soil particles are And peel or separate from the surface of soil particles. In step S3, the soil particles are shredded by the high temperature and high energy cross jet Jc, whereby the lattice structure of the soil particles is destroyed by the cross jet Jc, and the contaminants trapped inside the lattice are removed from the soil. Separate from the particles.
The separated contaminants are eluted in the slime or mixed with the air injected with the cross jet Jc. And it raises to the ground side in the state which eluted in the slime or in the state mixed with the gas which raises the boring hole H.

Further, in step S3, the filling material C is injected from the filling material injection port 21o, so that the filling material C sinks below the region cut by the intersecting jet Jc in the vertical direction. The sedimentation of the filling material C prevents the slime from which the pollutant has eluted from moving downward in the vertical direction in the region cut by the cross jet Jc.
For this reason, the slime from which the pollutants are eluted rises to the ground without sinking.

The slime and gas that have risen to the ground side in step S3 are prevented from penetrating the ground surface side and underground by the mouth tube 3 and the cover 3C (FIG. 2), and do not pollute the surrounding environment.
As described above, the pollutant concentration can be measured by analyzing the slime with the VOC concentration analyzer 106 in the slime, or the gas mixed with the pollutant is analyzed with the VOC concentration analyzer 104 in the gas. Can also be measured.
When the slime is analyzed to measure the pollutant concentration (“slime measurement” in step S4), a part of the slime that has risen to the ground side is extracted by the slime sample extraction device 10 (step S5).
Then, the extracted sample is sent to the VOC concentration analyzer 106 in the slime via a manual or conveying line (Lc1), and necessary processing is performed to measure the pollutant concentration (step S6).

In the case of measuring the pollutant concentration by analyzing the gas mixed with the pollutant ("gas measurement" in step S4), it passes through the boring hole H and the mouth pipe 3 and through the first slime transport pipe T1. The gas sent into the slime storage tank 4, that is, the mixture of air and gas phase contaminants is sucked by the gas sampling device 108 (step S7).
The gas sucked by the gas sampling device 108 is sent to the VOC concentration analyzer 104 in the gas via the line Lc2, and the contaminant concentration (for example, VOC concentration) is measured by a known technique (step S8).

Here, it is possible to determine the pollutant concentration using both the slime and gas that have risen to the ground side. In such a case ("both gas and slime are measured" in step S4), a part of the slime is collected by the VOC concentration analyzer 106 in the slime, and the gas rising to the ground side is sucked by the gas collector 108 (Step S9).
The collected slime is analyzed by the VOC concentration analyzer 106 in the slime to measure the pollutant concentration, and the sucked gas is processed by the VOC concentration analyzer 104 in the gas to measure the pollutant concentration. (Step S10). Then, the pollutant concentration is determined by referring to the pollutant concentration measurement result in the slime VOC concentration analyzer 106 and the pollutant concentration measurement result in the gas VOC concentration analyzer 104.

In Fig. 1 to Fig. 3, pollutants that were difficult to remove with the prior art are also separated and removed from clay and soil particles by cutting the contaminated soil with high temperature water cross jet Jc and eluted into the slime. Alternatively, it is in a state of being mixed with the gas that flows out from the borehole H.
That is, when the clay particles are shredded by the high temperature and high energy cross jet Jc, the contaminants electrically adsorbed on the clay particles are separated from the clay particles. Alternatively, the lattice-like structure of the soil particles is broken by a high-temperature and high-energy cross jet, and the contaminants trapped inside the lattice and / or the contaminants adsorbed on the surface of the soil particles are easily eluted.

In the conventional measurement of the concentration of pollutants, contaminants such as VOC that are taken into or adsorbed on the soil particles of the contaminated soil to be measured are difficult to separate from the soil particles. Therefore, in the prior art, contaminants such as VOCs that are taken into the soil particles of the contaminated soil or adsorbed on the surface of the soil particles are difficult to elute into water, so the actual content can be detected with a measuring instrument. It was impossible.
On the other hand, according to the above-described embodiment, the lattice structure of the soil particles is destroyed by the high temperature and high energy cross jet Jc, for example, the contaminants electrically adsorbed with the clay particles are separated or separated. Therefore, pollutants that could not be detected by the prior art, that is, pollutants such as VOC that are taken into or adsorbed on the soil particles of the contaminated soil become measurable. Therefore, compared with the conventional measuring method, the substance of the contaminated soil is measured more accurately.

FIG. 4 shows experimental results comparing the measurement results of the pollutant concentration measurement method described in FIGS. 1 to 3 with conventional measurement methods.
In the experiment shown in FIG. 4, in the slime collected as described in FIGS. 1 and 2 (measurement method described in FIGS. 1 to 3) and the in-situ aqueous solution (measurement method of the prior art). , The concentration of trichlorethylene (TCE) measured using "Gas Chromatograph-Photoionization Detection Method (PID-Photo)" (TCE soil elution amount) is compared.
In FIG. 4, the vertical axis represents the depth of the region where the contamination concentration was measured (the depth is deeper toward the upper side of the vertical axis), and the horizontal axis represents the amount of soil eluted by TCE.

More specifically, the measurement according to the prior art is performed by measuring a raw material sampled from the contaminated soil region at a stage before cutting the contaminated soil region with a high-temperature cross jet (the processing described in FIGS. 1 and 2 is performed). The position soil is measured by GC-PID.
The measurement method according to the first embodiment (the present measurement method) is performed in the same region after the measurement according to the related art is completed.

As apparent from FIG. 4, the amount of soil elution of TCE measured by the measurement method according to the first embodiment (this measurement method) is far greater than the amount of soil elution of TCE by the conventional technology.
Also from this, according to the pollutant concentration measuring method according to the present invention, the actual soil contamination can be grasped more accurately.

Next, a second embodiment of the present invention will be described with reference to FIGS.
The second embodiment of FIGS. 5 to 17 is an embodiment in which the pollutant concentration measuring method according to the first embodiment of FIGS. 1 to 4 is applied in combination with the contaminated soil purification method.
In the second embodiment of FIG. 5 to FIG. 17, a part of the slime and gas ejected to the ground side is collected, and the concentration of the pollutant is measured by the analytical equipment. Remove contaminants with the equipment. And if necessary, the slime that has been purified by removing contaminants is reused as a cutting fluid or a filling material.

In FIG. 5, the entire system (soil purification system) constructed by combining measurement of pollutant concentration and purification of contaminated soil is denoted by reference numeral 100.
The soil purification system 100 includes a construction machine 101, an excavator 1, a slime storage tank 4, a first slime aeration tank 5, a second slime aeration tank 6, a heavy metal removal device 7, and a concrete pump 8. And. These devices are provided to purify slime and gas from the contaminated area and remove the contaminants.

  Also in FIG. 5, as shown in FIG. 1, the slime sample extraction device 10, the VOC concentration analyzer 106 in the slime connected to the slime sample extraction device 10 via the line Lc <b> 1, the gas sampling device 108, The VOC concentration analyzer 104 in the gas connected to the gas sampling device 108 via the line Lc2 is provided. And the contaminant density | concentration is measured from the extracted slime and / or the extract | collected gas by the aspect demonstrated with reference to FIGS.

Also in FIG. 5, it is preferable that the jet jets J1 and J2 are composed of ultra-high pressure high-temperature water. And it is preferable that the temperature of high temperature water is the temperature which the water which is a cutting fluid does not vaporize, for example, 80-90 degreeC.
Although not clearly shown, the high-temperature water jets J1 and J2 are surrounded by a jet Ja of high-temperature compressed air. However, the compressed air jet Ja can be omitted.

In FIG. 5, the triple tube rod 2 is covered with a mouth tube 3, and a connection port 3 o is formed on the outer periphery of the mouth tube 3. One end T1a of the first slime transport pipe T1 is connected to the connection port 3o.
An end portion T1b on the side separated from the mouth tube 3 of the first slime transport pipe T1 opens from the upper side to the lower side in the slime storage tank 4.

  A first VOC recovery device 11 is disposed on the canopy 41 of the slime storage tank 4. The first VOC recovery device 11 has an adsorption device (not shown) containing an adsorbent such as activated carbon, and is configured to adsorb and collect contaminants such as VOC.

  The first VOC recovery device 11 communicates with the inside of the slime storage tank 4 by the first exhaust duct D1. A first blower 12 is interposed in the first exhaust duct D1. An end D1a on the tank 4 side in the first exhaust duct D1 is disposed in the vicinity of the other end T1b of the first slime transport pipe T1.

The slime S discharged from the first slime transport pipe T1 has already accumulated on the bottom 42 side of the slime storage tank 4 in FIG.
There is a drop between the end T1b of the first slime transport pipe T1 and the upper surface of the slime S stored in the slime storage tank 4. When the slime falls from the end T1b, the dropped slime collides with the stored slime S. By the collision, the soil (clay etc.) in the slime is finely crushed. If the clay is finely crushed and atomized, contaminants such as VOC associated with the clay are easily separated.

The slime storage tank 4 and the first slime aeration tank 5 communicate with each other through a second slime transport pipe T2. A first transport pump P1 is interposed at the end of the second slime transport pipe T2 on the slime storage tank 4 side.
The slime S in the slime storage tank 4 is sucked from the suction port P1a of the first transfer pump P1.

A high-rotation type (for example, rotation speed 3000 rpm) mixer 13 is interposed in the second slime transport pipe T2.
Since clay lumps are mixed in the slime flowing through the second slime transport pipe T2, a high-speed mixer is provided by interposing the high-speed mixer 13 in the second slime transport pipe T2. The clay lump in the slime is crushed by 13 and atomized.
If the clay lump in the slime is atomized, the VOCs in the slime can be easily separated by the aeration process in the first slime aeration tank 5 and the second slime aeration tank 6.

In the second slime transport pipe T <b> 2, a pipe heating device 14 is interposed in a region between the high rotation type mixer 13 and the first slime aeration tank 5.
Details of the pipe heating device 14 will be described later with reference to FIGS.
If the temperature of the slime flowing through the transport pipe T2 is raised by the heating action of the pipe heating device 14, the VOC contained in the slime can be easily separated.
In the illustrated example, the heating temperature by the pipe heating device 14 is about 130 ° C.

An end T2b on the side of the aeration tank 5 in the second slime transport pipe T2 opens in the horizontal direction above the inside of the first aeration tank 5.
In the first aeration tank 5, a slime circulation injection device 15 is installed above the vertical wall surface 51. The slime circulation injection device 15 is configured to inject in the horizontal direction.
The structure of the slime circulation injection device 15 will be described later with reference to FIGS.

The mixed flow (symbol Jsa in FIGS. 9 and 10) of the slime and air injected from the slime circulation injection device 15 travels straight and collides with the vertical wall 52 after injection.
The slime flowing through the second slime transport pipe T2 is pressurized by the first slime pump P1, and the slime sprayed in the horizontal direction from the end T2b of the second slime transport pipe 2T also goes straight. Collides with the vertical wall surface 52.

Even if a clay lump is contained in the slime, it is atomized by colliding with the vertical wall 52, and the VOC gas is easily separated.
The separated VOC gas is recovered by the second VOC recovery device 16 via the second exhaust duct D2. In the canopy 53 of the first slime aeration tank 5, the opening D2b of the second exhaust duct D2 is located in the vicinity of the vertical wall surface 52.

The slime sprayed in the horizontal direction from the end portion T2b of the second slime transport pipe 2T may not collide with the vertical wall surface 52. It is important that the slime is sprayed into the air.
By injecting the slime into the air instead of in the slime S stored at the bottom of the aeration tank 5, there are many opportunities for the soil particles or VOC in the slime to come into contact with the air, and the time for contact with the air becomes longer. This is because the aeration effect is improved.

In the first slime aeration tank 5, the end portion T2b of the second slime conveyance pipe T2 is joined to the slime circulation injection device 15, and the end portion T2b of the second slime conveyance pipe T2 and the slime circulation injection device 15 are connected. The same piping can be used.
The first slime aeration tank 5 and the second slime aeration tank 6 communicate with each other through a third slime transport pipe T3.
In the 3rd slime conveyance pipe T3, the 2nd conveyance pump P2 is interposed in the edge part by the side of the 1st slime aeration tank 5 side. The slime S in the first slime aeration tank 5 is sucked from the suction port P2a of the second transport pump P2 and sent to the second slime aeration tank 6.

A second VOC recovery device 16 is disposed on the canopy 61 of the second slime aeration tank 6.
The second VOC recovery device 16 has an adsorption layer made of an adsorbent such as activated carbon or zeolite (not shown), and is configured to adsorb and collect contaminants by the adsorption layer.
Instead of the VOC recovery device 16 having an adsorption layer, a refrigeration-type VOC concentration recovery device 16A can be used as described later with reference to FIG.

The second VOC recovery device 16 communicates with the upper portion of the first slime aeration tank 5 by the second exhaust duct D2. A second blower 17 is interposed in the second exhaust duct D2.
The second exhaust duct D2 branches to the third exhaust duct D3 at the branch point Pd. The third exhaust duct D3 communicates with the upper side of the second slime aeration tank 6.

There is a drop between the end T3b of the third slime transport pipe T3 and the upper surface of the slime S stored in the second slime aeration tank 6, and if the slime falls from the end T3b, It collides with the slime S stored in the tank 6.
By colliding, the solid content contained in the slime is atomized, and the contaminant contained in the slime is easily separated.
Here, the second slime pump P2 interposed in the third slime transport pipe T3 has a large impact when the transported slime collides with the slime in the tank 6 in addition to the slime transport function. It also has a function to

The bottom 62 of the second aeration tank 6 is equipped with an electrophoretic heavy metal recovery device 18.
The heavy metal recovery device 18 includes a cathode 18a, an anode 18b, and an electrode line Le connected to both electrodes.

By energizing the electrode line Le, heavy metals dissolved in the slime S or other ionized contaminants adhere to either the cathode 18a or the anode 18b.
If a certain amount of heavy metal or other ionized contaminants adheres to the electrodes 18a, 18b, the electrodes 18a, 18b are replaced. Then, heavy metals or other ionized contaminants are removed from the electrodes 18a and 18b removed from the second aeration tank 6.
Note that heavy metals and other contaminants that could not be removed by the heavy metal recovery device 18 are discharged from the fourth slime transport pipe T4.

The first slime aeration tank 5 may be equipped with stirring means such as a mixer M, as will be described later with reference to FIG.
In the first slime aeration tank 5, the internal slime is more active than the second slime aeration tank 6. On the other hand, in the second slime aeration tank 6, the flow of the slime S inside the tank is not so much.
Here, separation of heavy metals by electrophoresis can be more efficiently performed in a non-flowing state. Therefore, the second slime aeration tank 6 is in a state in which electrophoresis is easy. Therefore, heavy metals are separated by electrophoresis in the second slime aeration tank 6 on the downstream side.

A fourth slime transport pipe T4 is connected to the second slime aeration tank 6. In the 4th slime conveyance pipe T4, the 3rd pump P3 is interposed in the edge part by the side of the 2nd slime aeration tank 6 side.
The slime S in the second slime aeration tank 6 is sucked from the suction port P3a of the third transfer pump P3.
In the fourth slime transport pipe T4, an end T4b on the side separated from the second slime aeration tank 6 is opened above the hopper 19.

A first three-way valve V31 is interposed in the middle of the fourth slime transport pipe T4. A branch pipe TB branches from the first three-way valve V31, and an end of the branch pipe TB is a slime discharge port TBb.
In the fourth slime transport pipe T4, a second three-way valve V32 is interposed in a region between the three-way valve V31 and the end T4b. A branch pipe T40 branches from the second three-way valve V32.
The branch pipe T40 communicates with the heavy metal removing device 7. A slime discharge pipe T41 is connected to the heavy metal removing device 7, and the slime discharge pipe T41 opens above the hopper 19.
The heavy metal removing device 7 heats and supplies VOC, heavy metal, PCB, and the like from the slime by heating supplied through the fourth slime transport pipe T4 and the branch pipe T40. The slime from which heavy metals and PCB have been decomposed and removed, and the contaminants have been completely removed, is introduced into the hopper 19 through the slime discharge pipe T41.

  When it is known that the soil in the construction area is not contaminated with heavy metals, PCBs, etc., and the purified slime does not need to be recycled (as cutting fluid or filling material) or is recycled When it is desired to decrease the amount, the first three-way valve V31 is operated to open the outlet TBb side of the branch pipe TB. The slime processed in the second slime aeration tank 6 is transferred from the discharge port TBb of the branch pipe TB to an industrial waste treatment facility (not shown) by transfer means such as the industrial waste transfer vehicle 20.

The first three-way valve V31 closes the branch pipe TB side when recycling the entire amount of processed slime flowing through the fourth slime transport pipe T4 as a cutting fluid or filler, and removes the heavy metal removing device 7 and / Or open the hopper 19 side.
When the entire amount of processed slime is transported to an industrial waste treatment facility (not shown), the heavy metal removing device 7 and / or the hopper 19 side of the first three-way valve V31 is closed, and the branch pipe TB side is opened. .
When part of the processed slime flowing through the fourth slime transport pipe T4 is recycled and the rest is transported to an industrial waste treatment facility (not shown), the heavy metal removing device 7 of the first three-way valve V31 and / or The hopper 19 side is opened by an opening corresponding to the recycling amount, and the branch pipe TB side is opened by an opening corresponding to the amount conveyed to an industrial waste treatment facility (not shown).

The hopper 19 is connected to the concrete pump 8 via the fifth slime transport pipe T5. The slime put into the hopper 19 flows through the fifth slime transport pipe T5 and is sucked into the concrete pump 8.
The concrete pump 8 is connected to the purified triple pipe swivel 9 through the sixth slime transport pipe T6.

By operating the concrete pump 8, the slime from which contaminants have been removed (the slime recycled as the cutting fluid or filling material) is supplied again to the triple pipe rod 2 via the triple pipe swivel 9. That is, the slime for recycling is injected as a filling material C from the filling material injection port 21o of the first pipe 21 into the region where the purification method is applied. Alternatively, (the recycling slime) is ejected from the nozzles 221 and 222 of the triple tube rod 2 as a cutting fluid.
When the viscosity of the slime for recycling is high or the moisture content of the slime is high, a solidifying material or other chemicals may be added as appropriate according to the properties of the recycling slime.

  Immediately after the construction of the contaminated soil purification method, no slime for recycling is generated. In that case, a separately prepared solidifying material, for example, cement milk, is put into the hopper 19. The introduced cement milk is sent to the triple pipe rod 2 by the concrete pump 8 and injected as a filling material or a cutting fluid in the construction area of the soil purification method. More specifically, the slime from which contaminants have been removed is jetted as a cutting fluid from the pair of nozzles 221 and 222 of the triple pipe rod 2 of the excavator 1 and / or from the inlet 21o of the triple pipe rod 2. It is injected as filling material C.

  According to 2nd Embodiment of FIGS. 5-17, since a contaminant is removed from slime and it cleans, even if it refills the cleaned slime to an original position, no problem will generate | occur | produce. Further, the amount of slime to be treated as industrial waste is reduced by the amount used as the cutting fluid and / or the filling material C, and the cost necessary for the purification of contaminated soil is reduced by the amount that the cost of industrial waste treatment is reduced. Can be kept low.

With reference to FIGS. 6-8, the structure of the piping heating apparatus 14 is demonstrated.
6 and 7, the pipe heating device 14 includes a heating wire 141 and a chemical solution addition pipe 142.
The heating wire 141 is wound so as to spirally surround the second slime transport pipe T2. By energizing the heating wire 141, the slime flowing through the second slime transport pipe T2 is heated so as to rise to a normal temperature or higher.
Here, the heating temperature by the heating wire 141 is preferably about 130 ° C., for example. By heating the slime with the heating wire 141, the separation of the VOC contained in the slime is promoted.

The chemical solution addition pipe 142 communicates with the inside of the second slime transport pipe T2 so as to be orthogonal to the second slime transport pipe T2.
By analyzing the sample (specimen) extracted by the slime sample extraction device 10, the properties of the slime floating on the ground side can be grasped. In the pipe heating device 14, the necessary chemicals are appropriately added from the chemical solution addition pipe 142 to the slime flowing through the second slime transport pipe T <b> 2 in accordance with the analyzed properties of the slime.
For example, an aggregating agent, a neutralizing agent, a drug having an action of weakening the binding force between clay particles in the slime, and the like are added.

As shown in FIGS. 7 and 8, an in-line mixer 143 is installed inside the region where the heating wire 141 is wound around the second slime transport pipe T2.
The in-line mixer 143 promotes the atomization of the slime S flowing through the second slime transport pipe T2. Moreover, since the chemical | medical agent added from the chemical | medical solution addition pipe | tube 142 is fully mixed with a slime by the in-line mixer 143, the medicinal effect of a chemical | medical agent reveals rapidly.

With reference to FIG. 9, FIG. 10, the schematic structure of the slime circulation injection apparatus 15 is demonstrated. As described with reference to FIG. 5, the slime circulation injection device 15 is provided in the first slime aeration tank 5.
9 and 10, the slime circulation injection device 15 includes a high-pressure air injection pipe 151 and two slime circulation pipes 152. A slime pump 154 is interposed in each of the two slime circulation lines 152.

The two slime circulation pipelines 15 merge with each other between the high-pressure air injections 151. The other ends of the two slime circulation lines 152 communicate with the vicinity of the bottom of the first slime aeration tank 5, respectively.
An air introduction port 152c is formed in the vicinity of a portion (cross junction) Px where the slime circulation pipe line 152 joins the high pressure air injection pipe 151. The air inlet 152c is configured as a suction pipe.

By reducing the cross-sectional area of the flow path in the area where the air inlet 152c of the slime circulation line 152 is formed and increasing the flow velocity, negative pressure is generated in the flow path in the slime circulation line 152. Due to the negative pressure, air (outside air) is sucked into the slime circulation conduit 152 from the air inlet 152c.
Note that high-pressure air can be fed into the air inlet 152c from, for example, a compressor (not shown). Or it is also possible to send the iron powder, chemical | medical agent, etc. which have a purification effect | action through the air inlet 152c.

  When the slime circulation injection device 15 is operated, the high-pressure air injection pipe 151 is supplied with high-pressure air Fa1 from high-pressure air generation means (compressor or the like) (not shown). At the same time, the slime pump 154 is also operated. The slime pump 154 causes the slime in the first slime aeration tank 5 to flow in the two slime circulation pipes 152 (arrow Ys), and joins the high-pressure air injection pipe 151 at the cross junction Px.

  A mixed fluid Jsa of high-pressure air Fa1 and slime Ys is injected at high speed from the end of the high-pressure air injection pipe 151 on the aeration tank 5 side. The mixed fluid Jsa ejected at high speed collides with the vertical wall surface 52 on the front. The clay in the slime is atomized by the collision. The atomization of clay promotes the gasification of VOC in the slime.

Here, the slime sprayed in the horizontal direction may not collide with the vertical wall surface 52. It is important that the slime sprayed from the end T2b of the slime transport pipe 2T is sprayed toward the space of the aeration tank 5 that is not filled with slime, in other words, it is sprayed into the air.
By injecting slime into such a space, the opportunity for the soil particles or VOC in the slime to come into contact with air is increased, and the time for contact with air is increased, so the aeration effect is improved.

  Mixing the slime S flowing through the slime circulation line 152 with the air from the air introduction port 152c and the high-pressure air Fa1 flowing through the high-pressure air injection pipe 151 also provides an aeration effect and promotes VOC gasification. The

With reference to FIG. 11, the 1st modification of the 1st slime aeration tank 5 is demonstrated.
11, the slime aeration tank 5A according to the first modification has a bottom portion 54 that is inclined so that the center thereof is lowered in the left-right direction in FIG. Specifically, a flat portion 54h that is further deeper than the inclined surface is formed at the center of the bottom portion 54 of the slime aeration tank 5A.

The inclined bottom portion 54 is equipped with a plurality of mixers M. One mixer M is also provided in the flat portion 54h at the bottom center.
The slime aeration tank 5A includes a slime circulation injection device 15A similar to the slime circulation injection device 15 described with reference to FIGS.
In the slime aeration tank 5A, the stored slime S is always kept agitated by the plurality of mixers M, and the slime S reliably circulates in the tank 5A.

Next, a second modification of the first slime aeration tank will be described with reference to FIG.
In FIG. 12, the slime aeration tank 5B according to the second modification is configured such that the slime jet Js and the high-pressure air jet Ja are jetted vertically upward in the adjacent state. .

Since the slime jet Js and the high-pressure air jet Ja are intermingled both when rising and falling, it takes a long time for the slime to come into contact (impact) with the high-pressure air. Therefore, the aeration action with respect to the slime is good, and the gasification of VOC contained in the slime is promoted.
The slime aeration tank 5B according to the second modification is effective when the contaminant concentration of the slime is high.
Here, the slime jet Js and / or the high-pressure air jet Ja can also be constituted by cross jets.
Since the slime aeration tank 5B according to the second modification uses a silo tank, the sealing performance is high and the soundproofing effect is also high.

A third modification of the first slime aeration tank will be described with reference to FIG.
In FIG. 13, in the slime aeration tank 5C according to the third modification, a plurality of high-pressure air jets Ja are injected from the lower side to the upper side of the slime aeration tank 5C. A plurality of slime jets Js are sprayed from the upper side to the lower side of the slime aeration tank 5C.

  Since the slime jet Js and the high-pressure air jet Ja are sprayed opposite each other, there is a high probability that the slime jet Js will collide with the high-pressure air jet Ja, and the opportunity and time for the slime to be exposed to the high-pressure air are increased. Thus, the aeration effect is exhibited well. Therefore, the generation efficiency of VOC gas is improved.

  The horizontally arranged slime injection pipe Ts and the high-pressure air injection pipe Ta can also be configured to rotate in opposite directions (rotation in the direction of arrow R1 and rotation in the direction of arrow R2). . If the jets Js and Ja are configured to rotate in directions opposite to each other, the probability of a collision between the slime and the high-pressure air is further increased, and the opportunity and time for the slime to be exposed to the high-pressure air are further increased. As a result, the aeration effect is further improved and the generation efficiency of VOC gas is further improved.

A fourth modification of the first slime aeration tank will be described with reference to FIG.
In the slime aeration tank 5D according to the fourth modification, the horizontal air pipe Ta in the third modification of FIG. 13 is omitted, and instead, one high-pressure air nozzle Na is provided.
The high-pressure air nozzle Na is configured to generate a cyclonic air flow Fa in the tank 50. The swirl direction of the air flow Fa is opposite to the arrow R in FIG. On the other hand, the slime tube Ts rotates in the arrow R direction, which is the reverse direction of the swirl direction of the air flow Fa.
According to the fourth modification, the slime jet Js and the cyclonic air flow Fa collide suitably, the aeration effect is improved, and the VOC separation is promoted.

A fifth modification of the first slime aeration tank will be described with reference to FIGS. 15 and 16.
15 and 16, in the first slime aeration tank 5E according to the fifth modification, a cyclonic air flow Fa directed upward is formed by the high-pressure air injection nozzle Na provided at the bottom. A mixed jet injection device Nx is disposed above the tank. The mixed jet injection device Nx has a plurality of nozzles and extends in the horizontal direction. A composite jet Fx of slime and high-pressure air is injected from a plurality of nozzles of the mixed jet injection device Nx.
The composite jet Fx and the cyclonic air flow Fa collide suitably, the slime is well aerated, and the separation of the VOC contained in the slime is promoted.

Next, with reference to FIG. 17, a VOC recovery device 16A different from the second VOC recovery device 16 shown in FIG. 5 will be described.
In FIG. 17, the VOC recovery device 16 </ b> A has a brine tank (refrigerant tank) 161. A brine (refrigerant) inlet 162 and a brine outlet 163 are formed in the brine tank 161. A VOC pipe Lv is passed through the brine tank 161. The VOC piping Lv in the brine tank 161 is folded in a zigzag manner to constitute a heat exchanger.

  When the vapor phase VOC (arrow V1 in FIG. 17) passes through the brine tank 161, it is cooled by exchanging heat with the refrigerant (brine) Lc in the brine tank. The cooled “VOC gas and moisture in the gas phase” become “liquid phase VOC and liquid phase moisture” (arrow V2), and are discharged out of the brine tank 161. Since partly gaseous VOC is also dehumidified, it can be easily adsorbed and recovered by activated carbon or the like. Further, “liquid phase VOC and liquid phase moisture” (V2) are processed by a known means.

Also in the embodiment of FIGS. 5 to 17, as in the first embodiment of FIGS. 1 to 4, the pollutants that were difficult to remove by the prior art are peeled off and removed from the clay and soil particles, and slime It is in a state where it elutes in or is mixed with the gas that flows out of the borehole H.
If it is in a state of being eluted in the slime, the slime storage tank 4 and the first VOC recovery device, the first slime aeration tank 5 (including various modifications), the second aeration tank 6 and the second VOC recovery device. 17. Contaminants are easily and reliably removed from the slime by the electrophoretic heavy metal recovery device 18 and the heavy metal removal device 7 in the aeration tank 6.
Moreover, if the contaminant is mixed with the gas, it can be easily collected by suction before the gas diffuses into the atmosphere.

And as above-mentioned, in 2nd Embodiment of FIGS. 5-17, the slime from which the contaminant was removed is injected as cutting fluid from one pair of nozzles 221 and 222 of the triple pipe rod 2 of the excavator 1, And / or it is inject | poured as the filling material C from the injection hole 21o of the triple tube rod 2. FIG.
The slime from which the pollutants have been removed does not contain the pollutants, and no problem occurs even if the slime is backfilled in place. Then, the amount of slime to be processed as industrial waste is reduced by the amount used as the cutting fluid and / or the filling material C. As a result, the cost required for remediation of contaminated soil is reduced (to the extent that the cost of industrial waste treatment is reduced).

Next, a third embodiment of the present invention will be described with reference to the flowchart of FIG. 18 and FIG.
In the second embodiment, the pollutant concentration measurement method according to the first embodiment shown in FIGS. 1 to 4 is applied at the same time as the contaminated soil purification method. Is not used directly.
On the other hand, in the third embodiment shown in FIGS. 5 and 18, the pollutant concentration measured by the pollutant concentration measuring method according to the first embodiment of FIGS. It is used as.

  In FIG. 5, as described above, the boring hole H is drilled up to the lowest layer of the contaminated soil Gp. Then, the triple tube rod 2 of the excavator 1 is inserted into the drilled bore hole H. At the time of construction, the tip portion including the nozzles 221 and 221 and the filling material injection port 21o of the triple tube 2 and the simultaneous filling monitor 20 are rotated while being pulled upward.

Here, the construction area is cut and chopped by the cross jet Jc, the filling material C is injected into the entire construction area, the triple tube rod 2 is inserted again, and the cutting and chopping by the cross jet Jc and the filling material C are inserted. It is possible to repeat the injection.
In step S1 of FIG. 18, excavation and filling material are premised on the assumption that cutting, shredding, and injection of filling material C by cross jet Jc are repeated (constructed) multiple times. C is injected almost simultaneously.

In the cutting and shredding by the cross jet Jc, as described above with reference to FIG. 5, the hot water jets J1 and J2 are jetted from the nozzles 221 and 222 of the triple tube rod 2 to form the cross jet Jc. And the area | region (construction area | region) of a predetermined | prescribed radial direction dimension is cut and shredded by the cross jet Jc comprised with the hot water jet.
As described with reference to FIG. 5, the hot water jets J <b> 1 and J <b> 2 can be surrounded by the high-pressure air jet Ja and injected.

In the construction area cut and shredded by the cross jet Jc, the internal pressure rises by injecting a high-pressure fluid into a certain area. The slime is automatically discharged from the flow path K of the triple pipe rod 2 to the slime storage tank 4 via the first slime transfer pipe T1 by increasing the internal pressure of the excavated construction area where the slime is generated. Is done. Contaminants are eluted in the slime.
In the case of injecting the high-pressure air jet Ja, the contaminants separated from the soil particles and in the gas phase are mixed with the air of the high-pressure air jet Ja and discharged to the slime storage tank 4 in the state of the air-fuel mixture. Is done.

Filling material C is injected from the filling material injection port 21o into the construction area excavated and muddy.
Since no slime for recycling is generated at the beginning of excavation, for example, cement milk supplied separately is injected from the concrete pump 8 as a filling material.

As described above, the slime generated in the construction area flows into the slime storage tank 4 via the first slime transport pipe T1. A part of the slime flowing through the first slime transport pipe T1 is sampled (sampled) by the slime sample extraction device 10, and the concentration of contaminants in the slime is measured by an analysis facility (not shown). 18: Step S2).
In step S2 of FIG. 18, instead of analyzing the slime and measuring the pollutant concentration and the like, the gas sampling device 108 provided in the slime storage tank 4 collects the gas containing the vaporized contaminant, The pollutant concentration may be measured by sending it to the VOC concentration analyzer 104 in the gas via the line Lc2.
The measurement of the contaminant concentration in step S2 is the same as that described with reference to FIGS.

The slime sample is analyzed or the collected gas is analyzed to determine whether or not the pollutant concentration is greater than or equal to a threshold value (step S3). Here, the threshold value is set as a boundary value indicating whether or not to replace the entire amount of soil in the contaminated area (so-called “total amount replacement”).
When the contaminant concentration is equal to or higher than the threshold value (YES in step S3), a filling material having a large specific gravity is used in the second construction (step S4).
When the pollutant concentration is equal to or higher than the threshold (YES in step S3), when the slime from which the pollutant has been removed is reused as the filling material C, the pollutant concentration is repeated many times until the pollutant concentration falls below the environmental standard value. Therefore, there is a possibility that the cutting by the cross jet Jc and the injection of the filling material C must be repeated.

Therefore, when the contaminant concentration is equal to or higher than the threshold value (YES in step S3), a filling material having a large specific gravity is newly filled without reusing the slime from which the contaminant has been removed as the filling material C (step S4). ). Then, the contaminated soil in the construction area is completely replaced by the filling material having a large specific gravity.
In the second construction, if the contaminated soil in the construction area is completely replaced by the filling material having a large specific gravity, it is not necessary to repeat the cutting by the cross jet Jc and the injection of the filling material C in the construction area.

If the contaminant concentration is less than the threshold value in step S3 (NO in step S3), the process proceeds to step S5.
As in the second embodiment of FIGS. 5 to 17, the slime flowing into the slime storage tank 4 passes through the second slime transport pipe T <b> 2 in which the high-rotation mixer 13 and the pipe heating device 14 are interposed. Then, it is sent to the first slime aeration tank 5 and aerated. Then, in the second slime aeration tank 6, heavy metal and ionized contaminants are removed by the heavy metal recovery device 18.
Furthermore, the slime passes through the heavy metal processing device 7 as necessary, and the contaminants are completely removed. The slime from which the pollutants have been removed (processed slime) is sent to the excavator 1 as a filling material C or a cutting fluid via the concrete pump 8.

In step S5 of FIG. 18, the contaminated soil is cut by the cross jet Jc or the filling material C is injected, and the generated slime is purified by the treatment system shown in FIG. Or the cycle until it is again sent to the excavator 1 as a cutting fluid is executed.
When the cycle of step S5 is executed, the slime sample extraction device 10 extracts a slime sample (sample). And the extracted slime sample is analyzed and the density | concentration of the contaminant in slime is measured (step S6).
In step S6, the gas containing the vaporized pollutant may be analyzed by the VOC concentration analyzer 104 in the gas to measure the pollutant concentration.
The measurement of the contaminant concentration in step S6 is the same as that described with reference to FIGS.

In step S7, it is determined whether or not the pollutant concentration in the slime is a predetermined value, for example, an environmental reference value or less.
If the pollutant concentration is less than or equal to the environmental reference value (YES in step S7), the purification process is terminated.
If the pollutant concentration exceeds the environmental standard value (NO in step S7), step S5 and subsequent steps are repeated.

  In the third embodiment of FIG. 18, the sample slime is extracted by the slime sample extraction device 10 and the pollutant concentration in the slime flowing to the ground side is measured in the same manner as described with reference to FIGS. 1 to 4. Based on the pollutant concentration in the slime, it is possible to grasp in real time the contamination concentration in the underground purification method construction area. Alternatively, the gas collecting device 108 provided in the slime storage tank 4 collects the gas containing the vaporized pollutant and sends it to the VOC concentration analyzer 104 in the gas via the line Lc2 to measure the pollutant concentration. Therefore, it is possible to grasp in real time the contamination concentration in the underground purification method construction area.

And the contamination density | concentration in a purification construction method construction area | region can be grasped | ascertained in real time, and it can be determined whether a slime is reused as a cutting fluid or a filling material. When the slime is reused as a cutting fluid or filling material, if the number of repetitions of the cycles of steps S5 to S7 becomes too large, the slime is not reused and filling with a large specific gravity is performed as shown in step S4. By using materials, construction costs can be saved.
In addition, since the contamination concentration in the purification method construction area is grasped in real time and it is possible to accurately determine whether or not the cycle of steps S5 to S7 needs to be repeated, unnecessary work (from cutting and filling to excavation) The construction cost can be saved without reusing the machine 1.

FIG. 19 shows a fourth embodiment of the present invention.
In the first embodiment of FIGS. 1 to 4, the pollutant concentration is measured by the VOC concentration analyzer 106 in the slime and the VOC concentration analyzer 104 in the gas provided on the ground side. On the other hand, in 4th Embodiment of FIG. 19, the contaminant density | concentration contained in slime and / or gas is measured by the measuring device 310 provided in the underground side.
The measurement result by the measuring device 310 is transmitted to the unit 320 provided on the ground side via the signal transmission line CL300. The unit 320 has functions as, for example, an arithmetic device, a storage device, and a display device, and can be appropriately configured according to the configuration of the measurement device 310.
About another structure and effect in 4th Embodiment, it is the same as that of 1st Embodiment of FIGS. 1-4.

It should be noted that the illustrated embodiment is merely an example, and does not limit the technical scope of the present invention.
For example, in the illustrated embodiment, the cutting fluid jet constitutes a cross jet, but the cutting fluid jet may be jetted as it is, for example, in the horizontal direction without intersecting.
In the illustrated embodiment, the monitor 10 is pulled up while rotating to cut and fill the columnar contaminated soil region. However, the monitor 10 is pulled up while being swung by a predetermined angle without rotating. Thus, a panel-like contaminated soil region having a predetermined width may be cut and filled.

The figure which shows the whole structure of the system which constructs 1st Embodiment of this invention. The figure which showed the excavator periphery in FIG. 1 in detail. The flowchart which shows the procedure in 1st Embodiment. The figure which shows the effect of 1st Embodiment. The figure which shows the whole structure of the system which constructs 2nd Embodiment of this invention. The perspective view of the piping heating apparatus used by 2nd Embodiment. Sectional drawing of the piping heating apparatus shown in FIG. The figure which shows typically the inside of the piping heating apparatus shown in FIG. The top view of the slime aeration tank used in 2nd Embodiment. FIG. 10 is a plan view of the slime aeration tank of FIG. 9. Sectional drawing which shows the 1st modification of a slime aeration tank. The figure which shows typically the 2nd modification of a slime aeration tank. The figure which shows typically the 3rd modification of a slime aeration tank. The figure which shows typically the 4th modification of a slime aeration tank. The figure which shows typically the 5th modification of a slime aeration tank. The cross-sectional view of the slime aeration tank of FIG. The schematic diagram which shows the modification of the VOC collection | recovery apparatus used by 2nd Embodiment. The flowchart explaining 3rd Embodiment of this invention. The figure which shows the whole structure of the system which constructs 3rd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Excavator 2 ... Triple pipe rod 3 ... Mouth pipe 4 ... Slime storage tank 5 ... 1st slime aeration tank 6 ... 2nd slime aeration tank 7 ... Heavy metal removal device 8 ... concrete pump 9 ... triple swivel 10 ... slime sample extraction device 11 ... first VOC recovery device 12 ... first blower 13 ... high speed mixer 14 ... Pipe heating device 15 ... Slime circulation injection device,
16 ... 2nd VOC recovery device 17 ... 2nd blower 18 ... Heavy metal recovery device 20 ... Monitor C for simultaneous filling ... Filling material S ... Slime

Claims (4)

  An insertion process of excavating to an area in the ground where the pollutant concentration is to be measured and inserting an injection and injection device, a lifting process of lifting the injection and injection device, a slime and / Or a concentration measuring step for measuring the concentration of pollutants contained in the gas, and in the pulling step, a high-temperature fluid is injected from a nozzle provided above the injection and injection device, and the lower portion of the injection and injection device A pollutant concentration measurement method characterized in that a filler material is injected from an injection port provided in, and the contaminant is separated from soil particles by the kinetic energy and thermal energy possessed by a jet of high-temperature fluid.   2. The pollutant concentration measuring method according to claim 1, wherein the pollutant separated from the soil particles in the lifting step is eluted in the slime, floats to the ground side together with the slime, and the pollutant concentration is measured by collecting the slime on the ground side. .   2. The pollutant concentration measurement according to claim 1, wherein the pollutant separated from the soil particles in the lifting step floats to the ground side together with the air jetted together with the jet and collects the gas floating to the ground side to measure the pollutant concentration. Construction method.   The pollutant concentration measuring method according to claim 1, wherein in the concentration measuring step, the concentration of the pollutant separated from the soil particles in the pulling step is measured by a pollutant concentration measuring means arranged in the ground.

Images