KR101291435B1 - Method for remediation of contaminated soils using multi-function surfactant foam and apparatus for remediation of the contaminated soils - Google Patents

Abstract

PURPOSE: A method for remedying contaminated soil using multi-functional surfactant foam and an apparatus for the same are provided to completely prevent dust and volatile pollutants from being discharged to the atmosphere by covering the contaminated soil with surfactant foam. CONSTITUTION: A method for remedying contaminated soil includes the steps of: flattening contaminated soil on the ground (100); forming surfactant foam containing microorganisms by discharging air in a surfactant aqueous solution containing microorganisms (102); and forming a surfactant foam layer which biodegrades pollutants by carrying the microorganisms in the surfactant aqueous solution to penetrate through the pores of the soil (104). [Reference numerals] (100) Flatten contaminated soil; (102) Generate foam; (104) Form a surfactant foam layer; (106) Exhaust; (AA) Start; (BB) End

Description

Method for remediation of contaminated soils using multi-function surfactant foam and Apparatus for remediation of the contaminated soils}

The present invention relates to a contaminated soil purification treatment method and purification apparatus using a multifunctional surfactant foam.

Storage tanks containing liquid chemicals such as oils such as gasoline, diesel or bunker C oil, and various organic solvents are designed to satisfy durability and corrosion resistance, but nevertheless As it is used, it may gradually age and, for example, fine cracks may occur in weak areas. If a crack occurs, the stored material gradually flows out of the storage tank, which greatly pollutes the surrounding soil environment.

In particular, liquid substances (hereinafter, pollutants) flowing out of the storage tanks buried underground, which gradually diffuses in the soil and contaminates the unsaturated soil layer, easily reach the groundwater layer and degrade the groundwater. Furthermore, contaminants that remain in the unsaturated soil layer settle in the voids due to the capillary force between the soil particles and remain attached to the soil particles by surface tension.

On the other hand, the method for purifying the contaminated soil contaminated by the contaminants as described above, in-situ to restore immediately after purification in the contaminated area and the first time after moving the contaminated soil to another place There is an ex-situ that restores the position to. The in-situ treatment method and the off-site treatment method itself have various types and have respective advantages and disadvantages.

A representative example of the off-site treatment is a soil cultivation method. The soil cultivation method is a biological purification method, and spreads the soil contaminated with contaminants such as oil to a soil cultivation facility and spreads it flat, then adds microorganisms and nutrients to the contaminated soil and continues the soil. It is a purification method of flipping over.

1 is a view illustrating a conventional tillage contaminated soil purification method.

Basically, in order to cultivate contaminated soil, a cultivation facility is required. The cultivation facility includes a concrete floor 13 horizontally disposed on the ground surface 11 and a vinyl house 15 installed on the concrete floor 13. And a tank 23, a pump 25, and a watering device 27 for injecting microorganisms into the contaminated soil 17 suspended on the concrete floor 13.

The concrete floor 13 supports the contaminated soil 17 and blocks various contaminants flowing out of the contaminated soil 17 during operation, so as not to penetrate into the ground surface 11.

In addition, the vinyl house 15 provides a working space on the top of the contaminated soil 17 and blocks to some extent to prevent various fine dusts or volatile contaminants flying out of the contaminated soil 17 during operation.

In order to purify the contaminated soil using the purification treatment facility having the above structure, first, the contaminated soil transported from the contaminated area is placed on the concrete floor 13, and the contaminated soil is flattened by using an excavator 19 or a tractor. To stop (整地).

If a certain degree of stopping work is completed through the above process, the tank 23 is provided outside the plastic house 15, water and microorganisms and nutrients are mixed and pumped into the plastic house 15 workers (21) to spray the contaminated soil (17) through the watering device (27). In the meantime, it is necessary to continuously overturn the contaminated soil using a cultivator or other personnel.

The water sprayed through the watering device 27 is a mixture of water, microorganisms and nutrients, and the microorganisms biodegrade the pollutants by reacting with the pollutants mixed in the contaminated soil. In addition, the nutritional substance is to increase the activity of the microorganism, such as inorganic nitrogen, phosphorus or magnesium.

After a certain amount of time has passed after the watering operation, the tractor or excavator is used to turn over the soil again, and the watering operation is repeated.

By the way, the conventional tillage contaminated soil purification method has a need to use heavy equipment such as a tractor or an excavator because the process has to overturn the contaminated soil 17 frequently. The contaminated soil 17, which is usually spread for soil cultivation, is 5 to 10 meters in width and reaches about 100 meters in length, so without the above-mentioned heavy equipment, working progress is virtually impossible.

 In addition, even if the purification process is carried out inside the plastic house 15, there is a disadvantage that the operation can hardly proceed in winter, as long as the contaminated soil 17 is in contact with the atmosphere. Biological soil purification is the key to the biodegradation rate of microorganisms, because in winter (or cold regions such as polar regions) where the air temperature is low, microorganisms are significantly degraded and biodegradation of pollutants is rarely achieved.

In addition, the above-mentioned tillage-type purification treatment method also has a problem that the sprinkling liquid sprayed from the sprinkler 27 may cause secondary contamination. In fact, water, which accounts for the majority of the sprinkling liquid, can pass through the contaminated soil 17 and flow through the surface of the concrete floor 13 to the ground surface 11, where contaminants are mixed in the water, and the farmland It will result in polluting the surrounding soil. A facility to purify polluted soils, on the other hand, becomes a source of pollution that pollutes the soil.

In addition, the conventional tillage type soil purification treatment facility has a problem of generating a very large amount of fine dust and volatile contaminants during the soil tillage process. The fine dust and volatile contaminants can cause very serious harm to the workers inside the plastic house 15 as well as the surrounding residents or the ecosystem.

The present invention was created to solve the above problems, and thus completely shields the contaminated soil to be treated with a surfactant foam containing microorganisms, thereby completely blocking the air leakage of dust or volatile contaminants generated from the contaminated soil. As the surfactant bubbles burst sequentially, the biodegradable microorganisms, nutrients and oxygen contained in the bubbles are rapidly and continuously supplied into the contaminated soil through the pores of the soil by the action of the surfactant to maintain high efficiency biodegradation. In particular, since the surfactant foam acts as a thermal insulation and insulation, the temperature of the contaminated soil can be kept almost constant by minimizing the influence of the atmospheric temperature on the contaminated soil, so that the activity of microorganisms in the contaminated soil is optimally maintained and reliable. Polluting Soil Using Functional Surfactant Foam To provide a method and a re-purifying device is aimed.

The contaminated soil purification method using the multi-functional surfactant foam of the present invention for achieving the above object, the contaminated soil stopping step of spreading the contaminated soil contaminated by contaminants on the ground and flat; A bubble production step of blowing air into an aqueous solution of a surfactant containing microorganisms to form a bubbles containing a microorganism; The surfactant foam produced through the foam production step is covered with the upper portion of the contaminated soil, and the surfactant foam on the contaminated soil bursts, so that the microorganisms are loaded into the aqueous surfactant solution and pass through the pores of the soil to biodegrade contaminants. It characterized in that it comprises a surfactant foam layer forming step.

In addition, the purification treatment method; A vacuum pressure is applied to the lower side of the contaminated soil, characterized in that it further comprises an exhaust step for adjusting the rate of falling of the surfactant solution and microorganisms descending from the surfactant bubble layer.

In addition, the microorganism is characterized in that it includes a low temperature microorganism (psychrophile) or mesophilic microorganism (mesophilic microorganism).

In addition, the microorganism is characterized in that the mixed strain is a mixture of low temperature microorganism (psychrophile) and mesophilic microorganism (mesophilic microorganism).

In addition, the surfactant foam, characterized in that it further comprises a nutrient for microorganisms.

In addition, the purifying apparatus using the multi-functional surfactant foam of the present invention for achieving the above object, the surfactant containing microorganisms by receiving air in the state containing the water, the surfactant and the microorganism supplied from the outside therein Bubble tank and generating; A base portion on which contaminated soil contaminated by contaminants spreads; And a foam spraying means for forming a surfactant foam layer covering the contaminated soil by applying a surfactant bubble in the foam tank on top of the contaminated soil spreading on the base portion.

In addition, the bubble spraying means; And a plurality of foam nozzles installed on the base part, a plurality of pipelines connecting the foam tank and the nozzles, and a pump for pumping the surfactant foam to the nozzles through the pipelines.

In addition, the purification treatment apparatus is discharged to the outside by the vacuum pressure provided from the outside in a state covered with the contaminated soil to the outside, and the rate of descent of the surfactant aqueous solution and microorganism descending from the surfactant bubble layer It characterized in that it further comprises an exhaust means for adjusting.

In addition, the edge portion of the base portion, characterized in that the wall portion having a predetermined height and maintaining the surfactant bubble layer on the soil contaminated soil is further provided.

The contaminated soil purification treatment method and purification apparatus using the multifunctional surfactant foam of the present invention as described above is completely covered with a surfactant foam containing microorganisms to shield the contaminated soil to be treated, so that dust generated from the contaminated soil As well as completely blocking the outflow of volatile pollutants or airborne volatile pollutants, the surfactant bubbles burst sequentially from below, and the biodegradable microorganisms, nutrients, and oxygen contained in the bubbles are released from the soil by the action of the surfactant. Highly efficient biodegradation is maintained by supplying it quickly and continuously inside, and since surfactant foam plays a role of thermal insulation and insulation, it minimizes the influence of atmospheric temperature on the contaminated soil, so it can keep the temperature of contaminated soil almost constant. Optimal activity of microorganisms in the soil It is reliable.

1 is a view illustrating a conventional tillage contaminated soil purification method.
Figure 2 is a view showing for explaining the basic principle of the soil treatment method using a multi-functional surfactant foam according to an embodiment of the present invention.
Figure 3 is a block diagram showing the contaminated soil purification method using a multi-functional surfactant foam according to an embodiment of the present invention.
4 is a schematic structural diagram of a purification treatment facility using a multifunctional surfactant foam according to an embodiment of the present invention.
5 is a view showing another example of a purification treatment facility using a multifunctional surfactant foam according to an embodiment of the present invention.
FIG. 6 is a perspective view partially showing a purification treatment facility using the multifunctional surfactant foam shown in FIG. 5.

Hereinafter, one embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is a view showing for explaining the basic principle of the soil treatment method using a multi-functional surfactant foam according to an embodiment of the present invention.

Basically, in the contaminated soil purification method using the multifunctional surfactant foam according to the present embodiment, the multifunctional surfactant foam layer 31 is laminated on the contaminated soil 17 to be treated, and the contaminated soil 17 Is completely shielded (with respect to the atmosphere), the surfactant constituting the surfactant bubble layer 31 and microorganisms and nutrients are moved downward through the internal voids of the contaminated soil 17 as the bubbles 33 burst. And biodegradation of pollutants.

Referring to FIG. 2, it can be seen that the multifunctional surfactant foam layer 31 is stacked on the contaminated soil 17 loaded on the ground surface 11. The contaminated soil 17 is contaminated by oil, and contaminants A are located between the soil particles S constituting the contaminated soil 17. The pollutant (A) is adhered to the soil particles (S) to block the pores of the soil.

In the actual purification process, the contaminated soil 17 is flattened to a height of approximately 1 m or less in the treatment plant and covered by the surfactant foam.

The surfactant foam layer 31 is formed by supplying air after mixing a surfactant, microorganisms, and nutrients with water. Therefore, each of the bubbles 33 constituting the surfactant bubble layer 31 is mixed with the aqueous solution of the surfactant, microorganisms and nutrients.

In addition, the microorganisms include psychrophiles and mesophilic microorganisms. Depending on the working environment, the cryogenic microorganism or mesophilic microorganism may be selected and used independently, or the cryogenic microorganism and mesophilic microorganism may be mixed and applied. In addition, the nutrients include inorganic nitrogen, phosphorus, magnesium, etc., and increases the activity of the microorganisms during the biodegradation action of the microorganisms. Of course, other types of nutrients can be added as needed.

On the other hand, the multi-functional surfactant foam layer 31 is applied to the top of the contaminated soil 17, the foam 33 of the lower side (part in contact with the contaminated soil 17) is gradually submerged as it bursts first The surfactant foam should be fed continuously. The bubble 33 of the lower side pops first is a natural phenomenon that the bubble 33 first made pops first.

In any case, the multifunctional surfactant foam layer 31 is stacked on top of the contaminated soil 17 as above, and the surfactant foam layer 31 is maintained by the additional supply of the surfactant foam, thereby contaminating the soil 17. It is completely sealed. That is, the contaminated soil 17 is sealed by the surfactant foam layer 31. Accordingly, there is no fear that fine dust or volatile contaminants (VOCs) generated in the contaminated soil 17 are trapped in the lower portion of the surfactant foam layer 31 and blown into the air. There is no secondary pollution.

In addition, the surfactant foam layer 31 serves as a thermal insulation layer, and serves to insulate the contaminated soil 17 with respect to the atmosphere. As the known fact that air itself is a very effective heat insulator, the air-surfactant foam layer 31, which is mostly air, itself serves as a thermal insulation. Therefore, as shown in FIG. 4, when the treatment of the contaminated soil 17 is carried out inside the vinyl house 15, the contaminated soil 17 is double-insulated with the vinyl house and the surfactant foam layer 31 to be externally disposed. Will not be affected by the temperature.

In the surfactant foam layer 31 having the above characteristics, when the lower foam 33 of the foam layer 31 is turned off, the aqueous solution of the surfactant mixed with the foam 33 itself, the microorganism and the nutrient substance are soil particles (S). It is almost sucked into the gap of). Such flow characteristics are possible because of the low surface tension of the aqueous surfactant solution itself and the capillary force provided by the voids.

The microorganism and the aqueous solution of the surfactant passes between the soil particles (S) and removes the contaminants (A) adhered to the inside to biodegrade. In the place where the surfactant aqueous solution and the microorganism passed, there is no contaminant (A), so that the voids become empty. Therefore, the oxygen generated in the bubble 33 when the bubble 33 bursts reaches the bottom of the contaminated soil 17 through the pores and continuously maintains the activity of the microorganisms.

Figure 3 is a block diagram showing the contaminated soil purification method using a multi-functional surfactant foam according to an embodiment of the present invention.

As shown, the contaminated soil purification treatment method using the multifunctional surfactant foam according to the present embodiment, begins with the contaminated soil stop step (100).

In the contaminated soil stopping step 100, the contaminated soil excavated in the contaminated area and transported to the purification treatment facility (60 of FIG. 4) is poured into the base part 35 inside the plastic house (15 of FIG. 4) and the upper surface thereof. It's a process of leveling. At this time, the height of the contaminated soil for the base portion 35 may be approximately 1 m or less.

Along with the contaminated soil stopping step 100, foam production step 102 is also in progress. The foam production step 102 is a step of making a multi-functional surfactant foam, for example, by introducing water and surfactant, microorganisms and nutrients in the foam tank (37 of Figure 4) to blow out the air in water The process of making bubbles.

When the multifunctional surfactant bubble is filled in the foam tank 37 through the above process, the surfactant bubble is sprayed onto the contaminated soil 17 using a pump (39 in FIG. 4) to form a foam layer. An active removal product layer forming step 104 is performed. Through the surfactant foam layer forming step 104, the contaminated soil 17 is completely shielded from the multifunctional surfactant foam.

If the surfactant bubble layer 31 is formed as described above and left to stand, the foam layer 31 is gradually turned off and microorganisms begin to biodegrade contaminants. Of course, the surfactant bubble layer 31 must be maintained until the microorganisms completely decompose the contaminants.

In addition to the surfactant foam layer forming step 104, an exhausting step 106 may be performed. The exhaust step 106 is a step performed when the exhaust means is applied to the purification treatment facility 60, by applying a vacuum pressure to the lower side of the contaminated soil in the state where the surfactant foam layer 31 is applied, It is a step of controlling the falling rate of the aqueous surfactant solution and microorganisms falling from the surfactant bubble layer (31).

That is, when an intake pipe (47 in FIG. 5) is provided at the lower side of the contaminated soil 17, a vacuum pressure is applied to the intake pipe 47 from the outside, and the air around the intake pipe 47 is discharged. By forcibly pulling out to form a negative pressure in the voids, it is a process of increasing the descending speed of the aqueous surfactant solution and microorganisms and nutrients descending from the surfactant bubble layer (31). The evacuation step 106 is optional.

4 is a schematic structural diagram of a purification treatment facility 60 using a multifunctional surfactant foam according to an embodiment of the present invention.

As shown, the contaminated soil purification treatment facility 60 using the multi-functional surfactant foam according to the present embodiment, the microorganisms by receiving air in the state containing water, surfactant and microorganisms supplied from the outside therein Foam tank 37 for producing a surfactant bubble, a vinyl house 15 for providing an internal space (15a) to treat the contaminated soil, and the soil on the bottom of the vinyl house (15) And a foam spraying means for applying a surfactant foam in the foam tank 37 on the base portion 35 on which the 17 is spread, and on the contaminated soil 17 spread on the base portion 35.

The foam spraying means includes a pipeline 41 horizontally disposed above the contaminated soil 17, a plurality of nozzles 43 provided in the pipeline 41, and the foam tank 37. A multifunctional surfactant foam made in the pump (39) for pumping the nozzle 43 through the pipeline (41).

The vinyl house 15 is general, and receives solar heat to maintain the temperature of the internal space 15a higher than the temperature of the outside air. In addition, the vinyl house 15 should be provided with an entrance door to carry the contaminated soil 17 into the interior.

The base part 35 isolates the contaminated soil 17 from the ground surface 11 to block the movement of contaminants that may leach from the contaminated soil to the surrounding blue soil.

In fact, since the purification method according to the present embodiment uses foam unlike the conventional soil cultivation method, the amount of water in the surfactant solution is small, and water does not accumulate in the base 35. The water of the aqueous surfactant solution evaporates most of the reaction.

The base portion 35 may be any one of various types as long as it can separate the ground surface 11 and the contaminated soil 17. For example, concrete slabs or impervious waterproof sheets may be applied.

In order to purify the contaminated soil 17 using the purification treatment facility 60 having the above constitution, first, the contaminated soil 17 is poured into the base portion 35 and selected to a level of about 1 m or less and flattened.

Subsequently, a multifunctional surfactant is made in the foam tank 37 and pumped and sprinkled on top of the contaminated soil 17 through the nozzle 43. Surfactant bubbles sprayed on top of the contaminated soil (17), forming a multi-functional surfactant foam layer 31 is gradually lowered to biodegrade the contaminants in the contaminated soil. As the foam layer 31 is lowered, it is of course necessary to continuously supply the surfactant bubbles through the nozzle 43.

FIG. 5 is a view showing another example of the purification treatment facility 60 using the multifunctional surfactant foam according to an embodiment of the present invention, and FIG. 6 is a partial cutaway view of the purification treatment facility shown in FIG. 5. Perspective view.

Hereinafter, the same reference numerals as those of the above-mentioned reference numerals denote the same members having the same function.

Referring to the drawings, it can be seen that the wall portion 45 is provided on the upper edge portion of the base portion 35. The wall portion 45 is fixed along the edge of the base portion 35 and accommodates the contaminated soil 17 and the surfactant foam layer 31 therein.

By fixing the wall part 45 to the base part 35 in this way, the contaminated soil 17 and the surfactant foam layer 31 can be separated from the inner wall surface of the vinyl house, as well as one vinyl house 15. It is also possible to arrange a plurality of base portion 35 in the.

In particular, by making the height of the wall part 45 high, the thickness of the multifunctional surfactant foam layer 31 can be kept thick. As described above, since the wall portion 45 serves to trap the surfactant foam layer 31 in its inner region, the height of the wall portion 45 increases the height of the surfactant foam layer 31. It can be. The thicker the thickness of the multifunctional surfactant foam layer 31 is, the better the shielding and thermal insulation insulating ability.

On the other hand, a plurality of intake pipes 47 are provided on the base portion 35. The intake pipe 47 is a hollow pipe having a plurality of intake holes 47a formed at its periphery and is buried in the contaminated soil 17. In particular, the intake pipe 47 may be wrapped in a separate screen so that the contaminated soil 17 does not enter the intake pipe 47 through the intake hole 47a.

The intake pipe 47 is fixedly communicated with the main pipe 49 in a state extending outward through the one wall portion 45. In addition, a vacuum pump 55 is installed in the main pipe 49. Therefore, when the vacuum pump 55 is driven, air around the intake pipe 47 is sucked into the intake pipe 47 through the intake hole 47a, and the pressure around the intake pipe 47 is lowered.

As the pressure around the intake pipe 47 is lowered in this way, the downward movement speed of the surfactant aqueous solution and the microorganism and nutrients flowing from the upper portion to the lower portion of the contaminated soil 17 can be controlled, thereby adjusting the working speed. In particular, the oxygen generated by bursting the bubbles 33 is pulled to the lower side of the contaminated soil 17, so that the oxygen density of the lower side of the contaminated soil 17 is increased, so the activity of the microorganisms at the lower side of the contaminated soil 17 is very high.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

11: surface surface 13: concrete floor 15: vinyl house
15a: internal space 17: contaminated soil 19: excavator
21: Worker 23: Tank 25: Pump
27: watering device 31: multi-functional surfactant foam layer
33: bubble 35: base part 37: bubble tank
39: pump 41: pipeline 43: nozzle
45: wall portion 47: intake pipe 47a: intake hole
49: main pipe 55: vacuum pump 60: purification treatment facility

Claims (9)

A contaminated soil stopping step of spreading the contaminated soil contaminated by contaminants on the ground and leveling them;
A bubble production step of blowing air into an aqueous solution of a surfactant containing microorganisms to form a bubbles containing a microorganism;
The surfactant foam produced through the foam production step is covered with the upper portion of the contaminated soil, and the surfactant foam on the contaminated soil bursts, so that the microorganisms are loaded into the aqueous surfactant solution and pass through the pores of the soil to biodegrade contaminants. Soil purification method using a multi-functional surfactant foam, characterized in that it comprises a surfactant foam layer forming step. The method of claim 1,
The purifying treatment method includes;
Applying a vacuum pressure to the lower side of the soil contaminated, the soil contaminated soil using a multi-functional surfactant foam, characterized in that it further comprises an exhaust step for adjusting the rate of falling of the surfactant solution and microorganism descending from the surfactant foam layer Purification Method. The method of claim 1,
The microorganism, the soil soil purification method using a multi-functional surfactant foam, characterized in that it contains a low temperature microorganism (psychrophile) or mesophilic microorganism. The method of claim 1,
The microorganism is a contaminated soil purification method using a multi-functional surfactant foam, characterized in that the mixed strain is a mixture of low temperature microbiology and mesophilic microorganism. The method of claim 1,
The surfactant foam, soil contamination purification method using a multi-functional surfactant foam, characterized in that it further comprises a nutrient for microorganisms. A bubble tank for receiving air from a state of receiving water, a surfactant, and microorganisms supplied from the outside to generate air-containing surfactant bubbles;
A base portion on which contaminated soil contaminated by contaminants spreads;
A multifunctional surfactant comprising a foam spraying means for forming a surfactant foam layer covering the contaminated soil by applying a surfactant bubble in the foam tank on top of the soil contaminated on the base portion. Polluted soil purification equipment using foam. The method according to claim 6,
The bubble spraying means;
And a plurality of foam nozzles installed on the base part, a plurality of pipelines connecting the foam tank and the nozzles, and a pump for pumping the surfactant foam to the nozzles through the pipelines. Pollutant soil purification apparatus using functional surfactant foam. The method according to claim 6,
The purification treatment device,
In the state covered with the contaminated soil, by the vacuum pressure provided from the outside to discharge the air to the outside, the exhaust means for adjusting the rate of falling of the surfactant aqueous solution and microorganisms descending from the surfactant bubble layer is further included. Soil purification treatment apparatus using a multi-functional surfactant foam, characterized in that. The method according to claim 6,
On the edge of the base portion,
The soil soil purification apparatus using a multi-functional surfactant foam, characterized in that the wall portion further has a predetermined height to maintain the surfactant foam layer on the soil soil.

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