JP4044794B2 - Non-destructive geological pollution purification method and pressure bulkhead used therefor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a non-destructive geological contamination purification method and a pressure bulkhead used therefor, and more particularly, to a purification method and a pressure bulkhead that are not subjected to in-situ destruction without boring or the like on a geological layer to be purified. .
[0002]
[Prior art]
For example, geological contamination of soil and groundwater by volatile organic compounds (hereinafter referred to as VOCs) such as trichlorethylene and tetrachlorethylene has become a social problem, and there is an urgent need for remediation measures.
[0003]
Conventionally, the following technologies are generally known as technologies for purifying geological contamination.
(1) A method of creating a negative pressure environment underground through the borehole and volatilizing VOCs
(2) A method of pumping contaminated groundwater from a pumping well, purifying the groundwater with ground purification equipment, and returning the purified groundwater from the reduction well to the underground
(3) Method of promoting volatilization by inserting or injecting heat-generating materials or chemicals into the basement and heating VOCs
(4) Excavating contaminated soil with a hydraulic excavator, etc., and purifying the soil with a ground purification facility
(5) Purification method using microbe contamination decomposition activity by injecting microorganisms underground or by injecting chemicals that promote microbe activity through a borehole [0004]
However, the conventional techniques described above require drilling with a borehole or well, excavation with a hydraulic excavator, etc., and all techniques are methods that involve destruction of the original position, even for purification. For this reason, the original position cannot be restored to the state before contamination after purification. Moreover, the boring construction and the construction using a large machine are factors for increasing the purification cost.
[0005]
In addition, in the case of a narrow pollution site, it is often impossible to install a pumping well at an optimal position for purification because a large machine cannot be installed. Furthermore, in the case of groundwater contamination, the contamination range is wide, and construction such as boring for purification is restricted by residential areas and roads, and it is often impossible to take appropriate purification measures. Furthermore, it is difficult and costly to move the well position, such as when it is found that the well position is not optimal after the start of purification.
[0006]
[Problems to be solved by the invention]
The present invention has been made based on the technical background as described above, and achieves the following object.
The object of the present invention is that the purification can be carried out without causing the destruction of the purification site, the environment of the construction site is not restricted, the purification equipment can be easily installed, moved, and withdrawn. An object of the present invention is to provide a non-destructive geological pollution purification method capable of keeping costs low and a pressure partition used for the method.
[0007]
[Means for Solving the Problems]
The present invention employs the following means in order to achieve the above object.
That is, this invention is a method of purifying without destroying the geological layer to be purified by excavation or the like,
On the surface of the earth of the geological formation that is to the be purified, after defining a closed space,
By sucking the air in the sealed space with a suction device and making the sealed space have a negative pressure, a contaminant such as a volatile organic compound contained in the geological layer is sucked into the sealed space,
Furthermore, the non-destructive geological contamination purification method is characterized in that the sucked contaminants are sucked and discharged to the outside by the suction device.
[0008]
The sealed space can be formed by installing a pressure partition having an opening so that the opening faces the ground surface. A means for blocking the inflow of air into the pressure partition wall may be provided around the opening. In this case, as means for blocking the inflow of the atmosphere, embankment may be laid around the opening, or the opening may be buried below the ground surface.
[0009]
The present invention is also to purify without destroying the excavation geological layer that is to be purified, an opening is disposed so as to face the ground surface on the surface of the earth of the geological formation that is to the cleaning object, the internal A pressure partition for sucking in contaminants such as volatile organic compounds contained in the geological layer by making the pressure negative,
The pressure bulkhead used for the purification of geological contamination is characterized in that an airtight holding member for blocking inflow of air is provided at the end of the opening.
[0010]
The airtight holding member may be formed of a ring-shaped elastic body that can be deformed following the shape of the ground surface. The hermetic holding member may be formed of a sheet-like elastic body having a spreading portion that spreads on the outer periphery of the opening. Furthermore, the airtight holding member can also be constituted by a hard cylindrical body embedded in the geological layer.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an embodiment of a nondestructive geological pollution purification method according to the present invention. The geological layer 1 shown in FIG. 1 is contaminated with VOCs (indicated by reference numeral 2), and the following processing is performed with this geological layer 1 as a purification target.
[0012]
In this embodiment, the pressure partition 3 is a cylindrical member such as a cylinder or a rectangular tube, and has an opening 4. Inside the pressure partition 3, a suction tube 8 connected to a suction device 7 such as a vacuum pump is opened. The pressure partition 3 is made of a pressure resistant material such as a stainless steel plate, but any material may be used as long as it has pressure resistance. For example, you may comprise with the resin board which provided the reinforcement member in the inner periphery or the outer periphery. Further, the shape is not limited to a cylindrical shape, and may be various shapes such as a hemisphere.
[0013]
The pressure partition 3 is installed on the ground surface 5 of the geological layer 1 to be purified so that the opening 4 faces the ground surface 5. As a result, a sealed space 6 is formed on the ground surface 5. Then, by operating the suction device 7, the air inside the pressure partition 3 is sucked, and the internal pressure thereof is lower than the atmospheric pressure (negative pressure). Thereby, the movement of fluid such as underground air in the geological layer 1 is promoted, and the underground fluid is sucked into the pressure partition 3 as shown by arrows in FIG. Along with the suction of the underground fluid, the VOCs 2 contained therein also flows into the pressure bulkhead 3. At that time, the VOCs that existed as a liquid volatilize, and are further discharged to the outside through the suction pipe 8. The
[0014]
The concentration of VOCs discharged from the suction device 7 may be measured and monitored by a concentration measuring device (not shown) to manage the progress of the purification process. Further, an adsorption device using activated carbon or the like may be connected to the suction device 7 via a pipe line so as to adsorb VOCs. The above embodiment is based on the premise that VOCs are present by a preliminary survey, but the survey is performed by the same method as described above, that is, the presence of VOCs is confirmed by a concentration measuring device, Subsequent to this, it is possible to adopt a procedure of executing the purification process.
[0015]
If the airtightness between the end face of the opening 4 in the pressure partition 3 and the ground surface 5 is insufficient, the air flows into the pressure partition 3 and cannot effectively suck fluid such as underground air. . 2 and 3 show an embodiment in which means for blocking the inflow of air into the pressure bulkhead 3 is taken. That is, the embodiment shown in FIG. 2 is an example in which the embankment 10 is laid around the opening 4 of the pressure bulkhead 3 as means for blocking the inflow of air. Further, the embodiment shown in FIG. 3 is an example in which the opening 4 is embedded below the ground surface as means for blocking the inflow of air.
[0016]
In the embodiment of the purification method, the pressure partition itself is not provided with an airtight member. An airtight holding member may be provided on the pressure partition itself to block the inflow of air. Hereinafter, the suitable embodiment is described.
[0017]
The embodiment shown in FIG. 4 is an example in which a ring-shaped elastic body 11 is provided as an airtight holding member at the end of the opening 4 in the pressure partition 3. The ring-shaped elastic body 11 is a ring having the same shape as the shape of the opening 4, for example, a circular ring or a square ring, and has a predetermined thickness (between the inner and outer diameters) greater than the predetermined height and the thickness of the pressure bulkhead 3. Dimension).
[0018]
The ring-shaped elastic body 11 is made of, for example, a flexible rubber material. When the pressure partition 3 is installed, the ring-shaped elastic body 11 is deformed following the shape of the ground surface 5 and the contact area with the ground surface 5 is increased. Therefore, since airtightness between the end surface of the opening 4 and the ground surface 5 is maintained and inflow of the atmosphere can be prevented, fluid such as underground air can be sucked effectively.
[0019]
The embodiment shown in FIG. 5 is an example in which a sheet-like elastic body 12 is provided as an airtight holding member at the end of the opening 4 in the pressure partition 3. The sheet-like elastic body 12 has a spread portion 13 that spreads on the outer periphery of the opening 4. The sheet-like elastic body 12 is made of, for example, a flexible rubber material in the same manner as the ring-like elastic body 11 shown in FIG. 4, and in the state where the pressure partition 3 is installed, the sheet-like elastic body 12 follows the ground surface 5 and has a disk shape (the outer shape is circular). And a contact area with the ground surface 5 that is sufficiently larger than the thickness of the pressure bulkhead 3 is obtained.
[0020]
Then, by placing and fixing a loading body 14 such as embankment on the spread portion 13, the spread portion 13 is in close contact with the ground surface 5, and sufficient airtightness can be maintained. In the case of the embodiment shown in FIGS. 4 and 5, a fluid such as water may be permeated as a sealing material into the portion of the ground surface 5 that will be in contact with the ring-like elastic body 11 or the sheet-like elastic body 12. As a result, the adhesion to the ground surface is increased and the airtightness can be further enhanced.
[0021]
The embodiment shown in FIG. 6 is an example in which a cylindrical body 15 is provided as an airtight holding member at the end of the opening 4 in the pressure partition 3. The cylindrical body 15 is made of a hard material such as a steel material, and is thicker than the pressure partition 3. By embedding such a cylindrical body 15 below the ground surface, airtightness can be reliably maintained.
[0022]
According to the above embodiments, the following effects can be obtained.
(1) Since there is no need to install a well or excavate with a hydraulic excavator, the original geological condition will not be destroyed.
(2) Since there is no need for boring or large machines, the purification cost can be greatly reduced.
(3) Since there is no need for a pumping well, etc., it can be used even in a narrow pollution field. In addition, since there is no work such as boring for purification, there are no restrictions on purification measures due to residential areas or roads.
(4) After the start of purification, even if it is found that the installation position of the pressure bulkhead is not optimal, the installation position can be easily changed.
[0023]
【The invention's effect】
As described above, according to the present invention, it is possible to carry out purification without destroying the purification site, and without being restricted by the environment of the construction site, and it is possible to install, move, and withdraw purification equipment. It is easy and the construction cost can be kept low.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of a purification method according to the present invention.
FIG. 2 is a cross-sectional view showing another embodiment of the purification method.
FIG. 3 is a cross-sectional view showing still another embodiment of the purification method.
FIG. 4 is a cross-sectional view showing a preferred embodiment of a pressure bulkhead.
FIG. 5 is a cross-sectional view showing another embodiment of the pressure bulkhead.
FIG. 6 is a cross-sectional view showing still another embodiment of the pressure bulkhead.
[Explanation of symbols]
1: Geological layer targeted for purification 2: Volatile organic compounds (VOCs)
3: Pressure partition wall 4: Opening portion 5: Ground surface 6: Sealed space 7: Suction device 8: Suction tube 10: Filling 11: Ring-like elastic body 12: Sheet-like elastic body 13: Spreading portion 14: Loading body 15: Tube Body

Claims (8)

A method for purifying a geological layer to be purified without destroying it by excavation or the like,
On the surface of the earth of the geological formation that is to the be purified, after defining a closed space,
By sucking the air in the sealed space with a suction device and making the sealed space have a negative pressure, a contaminant such as a volatile organic compound contained in the geological layer is sucked into the sealed space,
Further, the non-destructive geological contamination purification method, wherein the sucked contaminant is sucked and discharged to the outside by the suction device. 2. The nondestructive geological pollution purification method according to claim 1, wherein the sealed space is formed by installing a pressure partition having an opening so that the opening faces the ground surface. 3. The nondestructive geological contamination purification method according to claim 2, wherein means for blocking the inflow of air into the pressure bulkhead is provided around the opening. 4. The non-destructive geological contamination according to claim 3, wherein the means for blocking the inflow of air is laying embankment around the opening or embedding the opening under the ground surface. Purification method. The geological formation that is to be purified in order to purify without destroying the excavation, the opening on the surface of the earth of the geological formation that is to the cleaning target is placed so as to face the ground surface, the internal negative pressure A pressure partition for sucking in contaminants such as volatile organic compounds contained in the geological layer,
A pressure bulkhead used for the purification of geological contamination, characterized in that an airtight holding member for blocking inflow of air is provided at an end of the opening. 6. The pressure bulkhead for use in purification of geological contamination according to claim 5, wherein the airtight holding member is made of a ring-shaped elastic body that can be deformed following the shape of the ground surface. 6. The pressure bulkhead used for the purification of geological contamination according to claim 5, wherein the hermetic holding member is made of a sheet-like elastic body having a widened portion extending on the outer periphery of the opening. 6. The pressure bulkhead used for the purification of geological contamination according to claim 5, wherein the airtight holding member is made of a hard cylindrical body embedded in the geological layer.

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