JP3160016B2 - Environmental protection method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an environmental protection method ,
Especially around areas that are contaminated or at risk of contamination,
The construction of a barrier to prevent the movement of pollutants from the area to the surroundings is to prevent the influence on the environment. Further, the trapping material is replaced when the trapping ability is reduced or deactivated.

[0002]

2. Description of the Related Art With the development of industry and the diversification of urban life, the problems of industrial waste and municipal waste have been greatly highlighted. In particular, in addition to an increase in the amount of waste treated, harmful substances contained in the waste, such as heavy metals such as mercury, cadmium, and chromium, flow out to living areas, for example, through groundwater. In addition, there is a high demand to prevent outflow of metals such as lead and zinc, ammonia nitrogen, trichloroethylene, and organic chlorine compounds.

[0003] For this purpose, it is a suitable solution to construct a blocking wall around a contaminated or at risk of contaminant to prevent the transfer of contaminants from that region to the surroundings. Indeed, it has been conventional to build concrete walls around the area, or even concrete impermeable walls at the bottom.

However, concrete walls have a high possibility of permeating heavy metals, and when cracks occur, they will intensively flow out therefrom.

On the other hand, Japanese Patent Application Laid-Open No. Sho 61-105500 proposes that a material having a high barrier property for heavy metals is injected into cracks or the like of a barrier wall.

[0006]

However, as far as it is considered only from the interruption of heavy metals and the like, it cannot be dealt with at all if cracks occur due to external factors such as earthquakes or aging. Moreover, even if a material for absorbing and holding a contaminant is contained in the constituent material of the barrier wall, as in the present invention described later, after the barrier wall is formed, contact with a liquid containing the contaminant eventually occurs. Repeated or aging of the capture material may reduce or deactivate its capture capacity. However, in this case, rebuilding the whole of the blocking wall newly increases construction cost and there is no effective means for preventing the outflow of pollutants for a long period of time required for the rebuilding.

[0007] Accordingly, a main object of the present invention is to provide an excellent blocking or trapping property of pollutants,
In order to regain the capture ability, especially when the capture material's ability to capture the contaminant is reduced or deactivated, it is necessary to replace it to maintain the ability to capture the contaminant and rebuild the entire barrier. The point is not to need it.

[0008]

SUMMARY OF THE INVENTION The above problem is around the contaminated or contamination risk is a region, in method of constructing a blocking wall for blocking the movement of contaminants to the surrounding from the area, contamination Surrounding areas that have been cleaned or may be contaminated.
Seen, a portion for blocking the liquid containing the contaminants, the liquid blocking unit
Provided on the outside of the minute, to build a cutoff wall Ru and a portion having a capture material that attracts and holds contaminants, the contaminants
The liquid containing liquid is blocked by the liquid blocking part,
In areas that have been compromised or are at risk of contamination,
The liquid containing the contaminant is blocked by the liquid blocking part.
If the liquid does not pass through the liquid blocking part,
The dyed material was captured by a portion having the capture material, other
On the other hand, the concentration of contaminants outside the barrier is detected.
However, when the detection concentration is increased, the capture of the capture material is performed.
The problem can be solved by judging that the capacity has been reduced or inactivated, and at that time, withdrawing the trapping material alone or together with the material holding the trapping material from the barrier wall and replacing it. In this case, it is preferable that the trapping material is held in a holder having a through hole smaller than the particle diameter, and is exchanged via the holder.

[0009]

According to the present invention, the blocking wall comprises a portion for blocking the liquid and a portion having a trapping material for adsorbing and holding the pollutant. The blocking portion blocks the liquid containing the contaminant and remains in the contaminated area. However, when the liquid containing the contaminant permeates the blocking portion, the trapping material adsorbs and holds the contaminant. In addition, the concentration of contaminants outside the barrier
If the detected concentration increases,
Judges that the trapping capacity of the trapping material has been reduced or deactivated, and
At the point of time, when the capture material alone or together with the material holding the capture material is pulled out of the blocking portion and replaced,
Capturability can be maintained. Moreover, unlike the case where the entire blocking wall is broken and rebuilt, only the trapping material is simply replaced, so that the replacement operation can be performed easily and quickly.

[0010]

The present invention will be described in more detail below. FIGS. 1 to 4 show a first example of the present invention, in which, for example, a barrier wall 2 is built around a waste dumping site.
Around such contaminated or potentially contaminated areas, a blocking wall 2 that prevents the transfer of contaminants from that area to the perimeter is preferably provided with an impermeable layer 3 below. It is constructed by reaching the water-impermeable layer 3. When there is no water-impermeable layer 3 or there is a risk of seepage underground water and there is a risk of infiltration, a bottom wall similar to a blocking wall can be constructed below the contaminated area by appropriate means. The bottom wall is desirably continuous with the blocking wall 2. If necessary, a liquid-impermeable sheet 4 can be provided inside the blocking wall 2 or the bottom wall.

In the present invention, the blocking wall 2 has a portion 20 for blocking the liquid and a portion 30 having a trapping material for adsorbing and holding pollutants. In the first example, the liquid blocking portion 20 is constituted by a mortar wall concrete wall 20A having a deep U-shaped cross section. The concrete wall 20A can be constructed by excavating the excavation groove 40, disposing a formwork (not shown) inside, and pouring concrete into the gap.

The part 30 with the trapping material is of the cassette type in this example. That is, the trapping material 30A made of, for example, activated carbon is accommodated in a holder 30B made of a metal net having eyes or holes through which the trapping material 30A does not pass. Also, on the upper part of the holder 30B,
A support portion for replacement, for example, a suspension ring 30C is attached. Further, when the trapping capacity of the trapping material 30A is reduced or deactivated, the trapping material 30A is drawn out from the liquid blocking part 20, that is, the concrete wall 20A, and is replaceable. This replacement is carried out by suspending from the ground by the suspending wire 41 or the like.
Can be carried out by suspending the cassette 30 having the above in the concrete wall 20A. The cassette 30
In the case where the walls are continuous in the length direction of the wall or are continuously connected at a distance, as shown in FIG. 4, the liquid-blocking sheet 42 made of a material such as metal or plastic has a barrier property at the space where the walls are separated. Can be enhanced. A plurality of cassettes 30 can be provided in the depth direction.

When the blocking wall 2 is configured as described above, the liquid containing the pollutant is blocked by the concrete wall 20A and stays in the polluted area. However, if a liquid containing a contaminant permeates due to a crack in the concrete wall 20A or the like, the liquid permeates into the cassette 30, and at this time, the trapping material 30A adsorbs and holds the contaminant. On the other hand, the capturing ability of the capturing material is reduced or deactivated due to aging . Therefore, the contaminants outside the blocking wall 2
Quality concentration and captures when the detected concentration increases
It is determined that the capturing ability of the material 30A has been reduced or deactivated,
At that point, the cassette 30 is removed from the concrete wall 20 and replaced with a new cassette. For example, as shown in FIG.
As shown in the figure, outside the barrier 2
A well 43 is provided, and a concentration meter 44 is inserted into the well,
Detect the concentration of pollutants, and if the concentration of
In the event that the trapping material 30A is trapped,
Judge that the cassette has been deactivated and replace the cassette.
It is preferred that Thereby, the contaminant trapping property can be maintained thereafter. Therefore, for example, in the case of constructing the barrier only with the concrete wall containing the trapping material alone, the workability is remarkably improved as compared with the necessity of breaking and rebuilding the entire barrier. In addition, when the cassette type is used, the replacement operation can be performed easily and quickly.

On the other hand, the above example is an example in which the trapping material 30A is held by the holder 30B.
Only 0A may be replaced. Further, without using a holder, only the trapping material 30A can be put into the concrete wall 20A, and when replacing the trapping material, the trapping material can be scraped or pumped up, and a new trapping material 30A can be put in place of the scraping or pumping-up. Concrete wall 20
For example, water may be applied to a portion of the container A for accommodating the cassette 30 so that the contaminant is dispersed and absorbed and held. If necessary, for example, mortar or the like that does not participate in the capture of contaminants can be added to the holder 30B together with the capture material 30A to provide a liquid blocking property.

In the present invention, the embodiments shown in FIGS. That is, first, as shown in FIG. 5, a guide wall 10 is constructed, and a long excavation groove 11 is excavated. In this excavation, when excavation is performed using a stabilizing liquid 12 such as bentonite, the hole wall is stabilized. Next, as shown in FIG. 6, a hollow holder having a large number of through holes 13 a, for example, a hollow tube 13 is inserted into the excavation groove 11. In this case, as shown in FIG.
The hollow pipes 13 are inserted into the digging groove 11 at intervals in such a manner that the capturing parts 5, 5...

When the spacer 14 is fixed around the hollow tube 13 for insertion, the centering is facilitated. The spacer 14 can be removed or buried later.

Thereafter, as shown in FIG. 7, a hollow space forming tube 15 with a bottom is inserted into the hollow tube 13. in this case,
The space forming pipe 15 may be inserted into the excavation groove 11 together with the hollow pipe 13. The space forming tube 15 is desirably bottomed so that the stabilizing liquid 12 does not enter from below. Instead of the space forming tube 15, a solid tube may be used.

When the insertion of the space forming tube 15 is completed,
As shown in FIG. 8, the solidifying material 16 is solidified by adding a hardening additive to the stabilizing liquid 12 and stirring to stabilize the hardening additive, or by replacing the stabilizing liquid 12 with, for example, cement.

After the solidifying material 16 has lost its fluidity or has solidified, as shown in FIG.
, And the extracted space is defined as a filling space 17. Then, as shown in FIG. 10, the contaminant trapping material 18 is charged into the hollow tube 13 and filled therein, and the trapping portions 5, 5,... Shown in FIG. Can be built in parts. If necessary, the hollow tubes 13, 13 can be connected to each other by the liquid blocking film 42A for blocking, and the liquid containing contaminants can be guided only into the hollow tube 13.

In the above example, the hollow tube 13 and the space forming tube 15 can be a metal tube or a plastic tube such as vinyl chloride. In order to facilitate removal of the space forming tube 15, an oil-based release agent can be applied to the inner surface of the hollow tube 13 or the outer surface of the space forming tube 15 or both. Sand or the like may be poured between them. Further, although the space forming tube 15 was used for forming the filling space 17 in the hollow tube 13,
It is also possible to adopt a method in which a bag or the like is used, a fluid such as water is injected into the inside thereof, and after the solidifying material 16 is solidified, the fluid is removed and the bag is removed.

When the hollow tube 13 is used, as shown in FIG.
A cylindrical cassette 300 filled with A can be used.

In the present invention, the trapping material 30A is embedded in the ground.
A barrier such as a concrete wall may be constructed between the wall constructed in the above and the contaminated area. In this case, after the liquid containing the contaminant permeates through the concrete wall, it is trapped by the trapping material 30A. However, if the permeability of the liquid of the wall formed with the trapping material 30A is high due to a low packing density or the like, permeation may occur without sufficient trapping, and Since moisture or groundwater in the ground flows into the non-contaminated area and lowers the concentration in the trapping material portion, it is preferable to dispose the trapping material in the portion to be cut off as in the above-described example. In this case, it is possible to prevent the inflow of moisture or groundwater in the ground into the non-contaminated area, and in a state where the concentration of the contaminant is high, and because the contaminant flows through the trapping material in a small amount, it is desirable to increase the adsorption trapping property. .

In the present invention, as for the trapping material, a substance which adsorbs or retains contaminants, for example, activated carbon, zeolite, vermiculite, kaolin, sodium bentonite, silica, blast furnace slag, and other clay minerals singly or plurally are mixed. Can be used in a state.
This type has ion exchange capacity and adsorption capacity, and can be used. In addition, one or more of the materials disclosed in the above publication can be used in combination. When the contaminant is ammonia nitrogen or the like, a trapping material corresponding to these can be used. Waste disposal sites may have many types of pollutants. Therefore, the types of trapping materials used for the trapping piles 4, 4,... Can be made different. The trapping material may be used as it is, but may be used in the form of pellets or aggregated or agglomerated particles. In addition, the surface of the capture material can be coated with other capture materials, especially those that dissolve over time in contact with a liquid.

[0024]

As described above, according to the present invention, the contaminant is excellently blocked or trapped, and the trapping material is replaced when the trapping ability of the trapping material is reduced or deactivated. As a result, the trapping ability can be re-established, and as a result, there is an advantage that the trapping property of the contaminant can be maintained at all times, and that it is not necessary to reconstruct the entire shielding wall.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a state where a blocking wall is constructed according to the present invention.

FIG. 2 is a perspective view of a replacement state of a cassette.

FIG. 3 is a cross-sectional view of an installed state of the cassette.

FIG. 4 is a plan view thereof.

FIG. 5 is a schematic sectional view of a first step of a working example of the present invention.

FIG. 6 is a schematic sectional view of a second step of the construction example of the present invention.

FIG. 7 is a schematic sectional view of a third step of a working example of the present invention.

FIG. 8 is a schematic sectional view of a fourth step of a working example of the present invention.

FIG. 9 is a schematic sectional view of a fifth step of a working example of the present invention.

FIG. 10 is a schematic sectional view of a sixth step of the working example of the present invention.

FIG. 11 is a perspective view of another example of replacement of a cassette according to the present invention.

FIG. 12 is a perspective view of the installation state.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Waste, 2 ... Blocking wall, 3 ... Water impervious layer, 4 ... Liquid impervious sheet, 11 ... Drilling groove, 12 ... Stable liquid, 13 ... Hollow holder, 13a ... Through hole, 15 ... Space formation Tube, 16: solidifying material, 17: space, 18: trapping substance, 20: blocking part,
20A: Concrete wall, 30: Capture part (cassette), 30A: Capture material, 30B: Holder, 300: Cassette.

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B09B 1/00 E02D 5/00-5/20 E02D 19/06-19/18 E02D 29/00-29 / 02

Claims (2)

(57) [Claims] Around 1. A contaminated or contamination risk is a region, in method of constructing a blocking wall for blocking the movement of contaminants to the surrounding from the region, the possibility of contaminated or polluted Surrounds an area with contaminants
A portion for blocking the liquid containing the quality, on the outside of the liquid blocking portion
Provided, contaminants build a cutoff wall Ru and a portion having a capture material for holding suction, a liquid containing the contaminant blocked by the liquid blocking moiety
In the contaminated or potentially contaminated area.
And the liquid containing the contaminants is
If it is not blocked by the liquid and passes through the liquid blocking part,
The contaminants in the permeate of the
And detect the concentration of contaminants outside the barrier
However, when the detection concentration is increased, the capture of the capture material is performed.
An environmental preservation method characterized in that it is judged that the capacity has been reduced or deactivated, and at that time, the trapping material alone or together with the material holding the trapping material is extracted from the barrier wall and replaced. 2. The environmental protection method according to claim 1, wherein the trapping material is held in a holder having a through hole smaller than the particle diameter, and is exchanged through the holder.