KR100427692B1 - system of Electrokinetic soil remediation - Google Patents

Abstract

The present invention relates to a system for purification of contaminated soil using electrokinetic machinery.

Purification system 2 according to the present invention, by using a plurality of electrokinetic 70a (80a) to purify the contaminated soil, and to purify and reuse the washing liquid used for the purification operation to quickly remove the contaminated soil In addition to purification, it can be useful to reduce the cost of purification.

Description

System of Electrokinetic Soil Remediation

The present invention relates to a purification system for purifying contaminated soil, and more particularly, to a purification system for contaminated soil using a voltaic device configured to purify contaminated soil as an electrokinetic device.

As is well known, a large amount of organic waste is generated by mass production and mass consumption as the industry develops, and environmental pollution such as water quality, air, soil, ocean, etc. has seriously emerged.

Among these environmental pollutions, especially water pollution and air pollution have a lot of influence on humankind, so there has been a great deal of attention from scientists and the global level, and continuous research has been continued.

On the other hand, soil pollution in environmental pollution is visually and sensibly affected by human beings rather than environmental pollution, so it is relatively less interested than other environmental pollution problems. It has been neglected, and therefore, there was a problem in that the cost and time consuming the purification of contaminated soil.

The soil pollution is a phenomenon in which pollutants penetrated into the ground pollute the lipids, and these pollutants pollute everything existing in the geology such as groundwater or underground air, and in particular, as the industry develops, various industrial wastes, including oil, etc. In addition, soil pollution became very serious as heavy metals were produced in large quantities.

On the other hand, the contamination of such soil is usually mainly due to heavy metal pollution, and the representative methods of purifying the soil contaminated with heavy metals include shielding treatment, steam extraction, soil washing technology, and the like. .

However, such shielding techniques include blocking holes, water holes, covering soil, planting works, etc. Depending on the level of soil pollution, these technologies are used. However, these techniques are not intended to purify contaminated soil, but rather to spread pollution sources. Because the main purpose is to prevent the pollution, soil pollution, which is a fundamental problem, cannot be solved.

In addition, steam extraction is a method for removing organic pollutants by vaporizing organic pollutants by lowering the pressure in the soil, which is effective for removing highly volatile organic pollutants, but it is costly to remove heavy metal pollutants. There was a problem.

In addition, the soil washing technology can purify the soil with high efficiency in a relatively short time by selecting the appropriate cleaning agent through the basic research according to the type of pollutant to be removed, but in the soil washing, the size of the soil particles is small, There was a limiting disadvantage that the flow of cleaning agent by pressure / vacuum was not smooth for clays of dense tissues with small porosity, and high pressure / vacuum was applied to such clay soils for smooth flow of the cleaning agent. While the energy cost to generate is increased, channeling phenomenon may occur, in which non-uniform gaps in the soil spread / move the detergent stream, which may cause the detergent and pollutants to move to non-contaminated areas. In addition to reducing cleaning efficiency, there is a risk of wastage of cleaning agents used and secondary pollution in non-contaminated areas. There was a problem.

Therefore, the present invention has been made to solve the problems described above, by supplying the washing liquid in the contaminated soil through electrokinetic equipment to filter heavy metals, to dissolve and clean the organic contaminants and to recycle the washing liquid. The purpose of the present invention is to provide a contaminated soil purification system using an electrokinetic device, which has improved economic efficiency.

1 is a block diagram showing a purification system according to the present invention

2 is a block diagram showing a centralized purification system according to the present invention

Figure 3 is a block diagram showing a purification system equipped with a waste liquid treatment tank according to the present invention

Figure 4 is a block diagram showing a purification system equipped with a waste liquid treatment tank according to another embodiment of the present invention

Figure 5 is a block diagram showing a purification system equipped with a waste liquid treatment tank according to another embodiment of the present invention

<Description of the symbols for the main parts of the drawings>

2: purification system 10: washing liquid supply means

12: supply tank 14: supply pipe

16: supply pump 20: washing liquid recovery means

22: drain pipe 24: drain pump

26: recovery tank 30: waste liquid treatment tank

30a: inlet pipe 30b: outlet pipe

40 ion exchange resin 50 anode plate

52: negative electrode plate 54: cation exchange membrane

60: iron chloride addition tank 62: sodium phosphate addition tank

62a: Potassium sulfate addition tank 64: Sodium hydroxide addition tank

70: positive electrode group 70a: positive electrode group

80: cathode copper group 80a: cathode copper

90: power supply unit 92: electric wire

The present invention for achieving the above object, in the purification system for purifying contaminated soil, the purification system is provided in the contaminated soil spaced apart at predetermined intervals in the same electrode in a row, between the electrodes A coin group provided with corresponding electrodes spaced at predetermined intervals in a row; One side of the supply pipe bent at one side adjacent to the positive electrode group is provided, one end of the supply pipe is provided with a supply tank in which the cleaning liquid is stored, on the supply pipe to discharge the cleaning liquid in the supply tank into the supply pipe. Washing liquid supply means consisting of a supply pump; One side of the drain pipe bent at one side adjacent to the cathode electrokinetic group is provided, respectively, one end of the drain pipe is provided with a recovery tank for collecting and storing the washing liquid containing the contaminant, on the drain pipe to the washing liquid in the drain pipe into the recovery tank Washing liquid recovery means consisting of a drain pump to be introduced; And a power supply unit connected to the electrokinetic group via a wire to supply power.

In addition, the purification system is provided with a waste solution treatment tank for purification to reuse the cleaning solution.

In addition, the waste liquid treatment tank is a treatment tank using an ion exchange resin that combines and purifies the heavy metals in the washing liquid, an electrolysis tank that separates and precipitates the heavy metal by reducing the washing liquid, and a chemical to chemically react to clean the complex compound and heavy metal of the washing liquid. It consists of any one of the settling tank.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing a purification system according to the present invention, as shown, the purification system 2 of the present invention is largely electrokinetic (70a) (80a), washing liquid supply means (10), The washing liquid recovery means 20 is made roughly.

The galvanic 70a, 80a is composed of a positive electrode 70a and a negative electrode 80a is provided in the contaminated soil, each of the galvanic 70a (80a) has the same electrode The electricity 70a, 80a is arranged in a line in the longitudinal direction.

The positive electrode (70a) is a plurality of positive electrode (70a) spaced at a predetermined interval is provided in the longitudinal direction to form a single positive electrode group 70, this positive electrode group 70 Between the plurality of negative electrode 80a is provided to correspond to the positive electrode 70a to form one negative electrode group 80.

The positive electrode 70a and the negative electrode 80a provided as described above are connected to the power supply unit 90 via a wire 92 to supply the same power to the electrokinetic groups 70 and 80 formed of the same electrodes. It is provided to.

That is, the positive electrode group 70 is all connected to the positive electrode of the power supply unit 90, the negative electrode group 80 is provided to all connected to the negative electrode of the power supply unit 90.

In addition, the washing liquid supply means 10 is provided with a supply tank 12 in which the washing liquid is stored, the supply tank 12 is connected to one end thereof in communication, the other end is bent vertically positive electrode group ( A supply pipe 14 is provided adjacent to the 70, the supply pipe 16 is provided on the supply pipe 14 to discharge the washing liquid from the supply tank 12 into the supply pipe (14).

On the other hand, the washing liquid recovery means 20 is provided on the opposite side of the washing liquid supply means 10 formed as described above, the washing liquid recovery means 20 is a recovery tank 26 in which the washing liquid containing the pollutant is recovered and stored One end thereof is connected to the recovery tank 26 in communication with the other end thereof, and the other end thereof is provided with a drain pipe 22 installed to be adjacent to the cathode electrokinetic group 80, and the drain pipe 22 is disposed on the drain pipe 22. And a drain pump 24 for discharging the washing liquid in the tank 22 into the recovery tank 26.

In addition, the cleaning solution of the purification system 2 made as described above may use a complex compound or an organic acid to increase the solubility of contaminants, and among them, representatively selected from Ethylene-Diaminetetraacetic Acid (EDTA) and citric acid. do.

And, the separation distance between the electrokinetic 70a (80a) is 0.5m to 5m, which is due to the narrow separation distance when the distance between the electrokinetic 70a (80a) is less than 0.5m. (70a) (80a) is required to increase the installation cost, if more than 5m has a disadvantage in that the decontamination time of the polluted soil is delayed and a large amount of power is consumed.

On the other hand, as described above, the current supplied from the power supply unit 90 to the electrokinetic 70a and 80a is 0.1 to 10 mW / cm 2, and the voltage forms an armature of 10 to 330 mW.

Purification system 2 according to the present embodiment made as described above are installed side by side in one direction in a state of spaced apart about 1m of the positive electrode 70a in the contaminated soil.

Then, the cathode copper (80a) is installed above or below the positive electrode copper group 70, the cathode copper (80a) is spaced about 1m away from the positive electrode (70a) to the positive electrode ( 70a).

Then, the power supply unit 90 is connected to the above electrokinetic devices 70a and 80a via a wire 92, and the supply pipe 14 connected to the supply tank 12 adjacent to the positive electrode group 70 is connected. The drain pipe 22 connected to the recovery tank 26 is installed in the vicinity of the negative electrode group 80.

Subsequently, when a power source consisting of a current of 0.1 to 10 mA / cm 2 or a voltage of 10 to 330 mA is supplied from the power supply unit 90 to the electrokinetic 70a and 80a of the purification system 2 provided as described above, 2 flows from the positive electrode 70a to the negative electrode 80a.

Then, at this time, the washing liquid discharged from the supply tank 12 by the supply pump 16 flows into the supply pipe 14, and the washing liquid is contaminated by the electroosmotic phenomenon by the flow of current as above. The soil is introduced into the drain pipe 22.

At this time, the cleaning liquid is dissolved in organic contaminants when passing through the contaminated soil, ionized heavy metals into the drain pipe 22 to purify the contaminated soil.

Then, the washing liquid containing the contaminant introduced into the drain pipe 22 as described above is introduced into the recovery tank 26 while rapidly flowing in the drain pipe 22 by the drain pump 24.

On the other hand, the soil purification process using the electrokinetic 70a (80a) as described above neutralizes the hydrogen ions generated at the positive electrode and the hydroxyl group generated at the negative electrode by electric reaction by injecting a buffer solution into the washing solution (electrolyte) The cleaning agent is injected into the soil while adjusting the pH.

Electrodynamic purification is an on-site soil purification technology that removes contaminants by placing electrodes in contaminated soil and applying a low DC current. Electric power phenomenon can be classified into three categories. Electroosmisis, the movement of metals or ions in the direction of the opposite electrode, electromigration, the phenomenon of colloid or charged particles moving in the direction of the opposite electrode due to the potential difference. It is called electrophoresis. The electroosmotic refers to a phenomenon in which a liquid in the medium moves in a specific direction when an electric field is present in a porous medium such as soil. The reason why electroosmosis occurs is that most soil particles generally have a weak negative charge, so that positive charges are collected in the spaces between the particles, and when the current flows, the liquid in the soil moves toward the cathode. In order to generate the electroosmotic in the soil, the anode and the cathode are installed around the polluted area, and if the current is supplied to the polluted area from the power source through these electrodes, the above-mentioned electroosmotic phenomenon is generated and the polluted soil can be purified will be.

2 is a block diagram showing a purification system according to a second embodiment of the present invention, the same reference numerals are assigned to the same parts as the above-described embodiment, and repeated descriptions thereof will be omitted, and only different points will be described. .

As shown, the purification system 2 according to the present embodiment is for purifying intensively contaminated soil, and installs one negative electrode 80a where the pollution of the soil occurs intensively. In the periphery of the far east electric 80a, a plurality of positive electrode electric 70a is provided and provided.

Galvanic 70a (80a) provided as described above is provided by being connected to the power supply unit 90 via a wire 92, a plurality of positive electrode 70a is all connected to the cathode of the power supply unit 90 The negative electrode 80a is connected to the positive electrode of the power supply unit 90.

Purification system 2 according to the present embodiment made as described above of the positive electrode 70a through the soil contaminated by the electroosmotic phenomenon of the cleaning liquid flowing in the supply pipe 14 adjacent to the positive electrode 70a. It is introduced into the drain pipe 22 on the side of the negative electrode 80a provided in the center portion.

Then, the washing liquid is introduced into the drain pipe 22 while passing through the contaminated overall soil around the cathode electromotive unit 80a, thereby dissolving organic contaminants in the contaminated soil and ionizing heavy metals to contaminate the contaminated soil. The soil will be cleaned.

3 is a block diagram showing a purification system according to a third embodiment of the present invention, the same reference numerals are assigned to the same parts as the above-described embodiment, and repeated descriptions thereof will be omitted, and only different points will be described. .

As shown, the purification system 2 according to the present embodiment is to be used to purify and reuse the washing liquid recovered and stored in the recovery tank 26 while containing the pollutant.

The purification system 2 is provided with a waste liquid treatment tank 30 between the recovery tank 26 and the supply tank 12, and the waste liquid treatment tank 30 serves as an inlet pipe 30a and an outlet pipe 30b. The recovery tank 26 and the supply tank 12 are provided in communication with each other.

In the waste liquid treatment tank 30, an ion exchange resin 40 is provided in which heavy metals, which are contaminants contained in the washing liquid, are combined to separate from the washing liquid.

Here, citric acid is used as the washing liquid used in the present embodiment, not the complex compound, and the ion exchange resin 40 is provided as a cation exchange resin.

Purification system 2 according to the present embodiment made as described above is the waste liquid treatment tank 30 through the inlet pipe (30a) is discharged from the recovery tank 26, the cleaning liquid for purifying the contaminated soil as in the first embodiment Flows into.

As described above, the washing liquid introduced into the waste liquid treatment tank 30 passes through the ion exchange resin 40 made of the cation exchange resin, and the heavy metal contained in the washing liquid is chemically reacted with the ion exchange resin 40 to be attached and attached. The heavy metal is separated and regenerated washing liquid is recirculated into the supply tank 12 of the washing liquid supply means 10 through the discharge pipe (30b).

4 is a block diagram showing a purification system according to a fourth embodiment of the present invention, the same reference numerals are assigned to the same parts as the above-described embodiment, and repeated descriptions thereof will be omitted, and only different points will be described. .

As shown, the purification system 2 according to the present embodiment is to be used to purify and reuse the washing liquid recovered and stored in the recovery tank 26 while containing the pollutant.

The purification system 2 is provided with a waste liquid treatment tank 30 between the recovery tank 26 and the supply tank 12, and the waste liquid treatment tank 30 serves as an inlet pipe 30a and an outlet pipe 30b. The recovery tank 26 and the supply tank 12 are provided in communication with each other.

On the other hand, the above-described waste liquid treatment tank 30 is provided with a positive electrode plate 50 and a negative electrode plate 52 connected to the power supply unit 90, and the positive electrode plate (50) (52) between the positive electrode plate (50) 50 is provided with a cation exchange membrane 54 which separates and separates the negative electrode plate 52.

In addition, the inlet pipe (30a) and the discharge pipe (30b) is formed on one side of the waste liquid treatment tank 30 is provided with a negative electrode plate 52 is connected in communication with the recovery tank 26 and the supply tank 12, respectively It is provided.

Purification system 2 according to the present embodiment made as described above is the waste liquid treatment tank 30 through the inlet pipe (30a) is discharged from the recovery tank 26, the cleaning liquid for purifying the contaminated soil as in the first embodiment Flows into.

As described above, the washing liquid introduced into the waste liquid treatment tank 30 is reduced by the electrode reaction generated in the anode plate 52, and heavy metal is separated and precipitated or deposited on the cathode plate 52, and the heavy metal is separated in this way. The regenerated washing liquid is introduced into the supply tank 12 through the discharge pipe 30b and stored.

On the other hand, the cation exchange membrane 54 is blocked to prevent the H ⁺ ions generated from the positive electrode plate 50 reacts with the regenerated washing liquid, that is, EDTA, to reduce the function of the complex compound.

In addition, the washing liquid regenerated by the heavy metal is separated as described above of the washing liquid supply means 10 through the discharge pipe (30b) formed on one side of the waste liquid treatment tank 30 is provided with a negative electrode plate 52, such as the inlet pipe (30a) It is recirculated into the supply tank 12 and circulated.

5 is a block diagram showing a purification system according to a fifth embodiment of the present invention, the same reference numerals are assigned to the same parts as the above-described embodiment, and repeated descriptions thereof will be omitted, and only different points will be described. .

As shown, the purification system 2 according to the present embodiment can purify and reuse the washing liquid recovered and stored in the recovery tank 26 while containing the pollutant between the recovery tank 26 and the supply tank 12. The waste liquid treatment tank 30 is provided.

The waste liquid treatment tank 30 is composed of three addition tanks, which are provided with an iron chloride addition tank 60, a sodium phosphate addition tank 62, and a sodium hydroxide addition tank 64.

The iron chloride addition tank (60) binds to the complex compound of eddiee and iron in the washing solution of the eddiee combined with heavy metals, the heavy metal is formed to exist in the ionic state.

The sodium phosphate addition tank 62 is a complex compound in the iron chloride addition tank 60 is present as it is combined with iron, and the heavy metal present in the ionic state is formed to be precipitated and removed while combined with phosphate.

In addition, the sodium hydroxide addition tank 64 is regenerated by combining the complex compound of eddiey present in the state combined with iron with sodium, and the iron separated from the complex is formed to precipitate out as iron hydroxide form.

On the other hand, the potassium sulfate addition tank 62a which replaces the sodium phosphate addition tank 62 may be comprised between the iron chloride addition tank 60 and the sodium hydroxide addition tank 64 mentioned above.

The potassium sulfate addition tank (62a) is a complex compound introduced from the iron chloride addition tank (60) is present in the state combined with iron, heavy metals in the ionic state is formed to precipitate and remove while combined with sulfate. .

Purification system 2 according to the present embodiment made as described above is discharged from the recovery tank 26 to clean the contaminated soil as in the first embodiment, the iron chloride addition tank 60 of the waste liquid treatment tank 30 Flows into.

After purifying the contaminated soil as described above, in the iron chloride addition tank 60 of the waste liquid treatment tank 30 into which the washing solution of the eddiei combined with heavy metals was introduced, the editie, which is a complex compound in the washing liquid, is combined with iron. It exists as an ionic state.

Thereafter, the washing solution is introduced into the sodium phosphate addition tank 62 from the iron chloride addition tank 60, and the introduced washing solution is present in the sodium phosphate addition tank 62 as the complexing compound, as it is in combination with iron. Heavy metals present in the ionic state are removed by precipitation with the phosphate.

At this time, even if the potassium sulfate addition tank 62a is provided in place of the sodium phosphate addition tank 62, in the potassium sulfate addition tank 62a, as in the sodium phosphate addition tank 62 described above, It is present as it is combined with iron, and the heavy metal present in the ionic state is removed as it is combined with the sulfate precipitates.

In addition, the washing solution discharged from the sodium phosphate addition tank 62 or the potassium sulfate addition tank 62a and introduced into the sodium hydroxide addition tank 64 is present in a state in which the sodium hydroxide addition tank 64 is combined with iron. The complex compound of idieti that was being used is combined with sodium to be regenerated, and the iron separated from the complex compound is formed to precipitate out as iron hydroxide.

On the other hand, the regenerated washing liquid is discharged from the sodium hydroxide addition tank 64 is re-introduced into the supply tank 12 of the washing liquid supply means 10 is circulated.

As described above, the contaminated soil purification system according to the present invention can quickly install the purification system on the contaminated soil to quickly clean the contaminated soil and reuse the cleaning solution used for purification. It can be effective to reduce the purification cost required.

Claims (9)

In the purification system (2) for purifying contaminated soil, The purification system 2 is provided in the contaminated soil with the same electrodes spaced apart in a row at predetermined intervals, and between the electrodes, corresponding electrodes are arranged in a row at a predetermined interval spaced apart from the electrokinetic group 70. 80; One side of the supply pipe 14 bent at one side adjacent to the cathode electrokinetic group 70 is provided, one end of the supply pipe 14 is provided with a supply tank 12 in which the washing liquid is stored, and the supply pipe ( 14, washing liquid supply means (10) consisting of a supply pump (16) for discharging the washing liquid in the supply tank (12) into the supply pipe (14); One side of the drain pipe 22 bent at one side adjacent to the cathode electrokinetic group 80 is provided, one end of the drain pipe 22 is provided with a recovery tank 26 for collecting and storing the washing solution containing the contaminant. On the drain pipe 22, the washing liquid recovery means 20 consisting of a drain pump 24 to introduce the washing liquid in the drain pipe 22 into the recovery tank 26; Contaminated soil purification system using a voltaic iron, characterized in that it comprises a; power supply unit 90 is connected to the electrokinetic group (70) (80) via a wire (92) to supply power. The method of claim 1, The washing liquid is any one selected from EDTA, citric acid in order to increase the solubility of the pollutant, the soil purification system using electrokinetic. The method of claim 1, Separation distance between each of the galvanizers (70a, 80a) forming the voltaic group (70, 80) is 0.5m to 5m, characterized in that the soil purification system using a voltaic. The method of claim 1, The current supplied from the power supply unit 90 to the electrokinetic device (70a) (80a) is 0.1 to 10 ㎠ / ㎠, characterized in that the soil contaminated soil purification system using. The method of claim 1, Between the recovery tank 26 and the supply tank 12, the waste liquid treatment tank 30, which contains the pollutant and is recovered into the recovery tank 26 and separated from the heavy metal, can be reused, and the inlet pipe 30a. And an outlet pipe (30b) are provided in communication with the recovery tank 26 and the supply tank (12), respectively, in the waste liquid treatment tank 30, the ion exchange resin (40) to combine the heavy metal to separate from the wash liquid Polluted soil purification system using an electrokinetic device, characterized in that provided. The method of claim 1, Between the recovery tank 26 and the supply tank 12, the waste liquid treatment tank 30, which contains the pollutant and is recovered into the recovery tank 26 and separated from the heavy metal, can be reused, and the inlet pipe 30a. And the discharge pipe 30b are provided in communication with the recovery tank 26 and the supply tank 12, respectively, and the waste liquid treatment tank 30 has a positive electrode plate 50 and a negative electrode plate 52 connected to the power supply unit 90. A cation exchange membrane 54 is provided between the cathode plate 50 and the anode plate 52 to isolate the cathode plates 50, 52, and the anode plate 52 is provided. One side of the waste liquid treatment tank 30 is provided with an inlet pipe (30a) and the discharge pipe (30b) so as to communicate with the recovery tank 26 and the supply tank 12, respectively, purification of contaminated soil using a coin machine system. The method of claim 1, Between the recovery tank 26 and the supply tank 12 is provided with a waste liquid treatment tank (30) in communication with the pollutant containing the contaminant so as to separate the stored washing liquid from the heavy metal and reuse it. , The waste liquid treatment tank 30 introduces a washing solution containing a contaminant from the recovery tank 26 so that the complex compound is combined with iron and the heavy metal is added in an ionic state; The sodium chloride phosphate addition tank 62 is provided to allow the complex compound introduced from the iron chloride addition tank 60 to be combined with iron, and the heavy metal present in the ionic state to be combined with phosphate to precipitate / remove the heavy metal; Sodium hydroxide addition tank (64) provided to regenerate by combining the complex compound combined with iron introduced from the sodium phosphate addition tank (62) with sodium, precipitated / removed as iron hydroxide; Polluted soil purification system using an electrokinetic device, characterized in that made. The method of claim 7, wherein Between the iron chloride addition tank 60 and the sodium hydroxide addition tank 64 of the waste liquid treatment tank 30, the complex compound introduced from the iron chloride addition tank 60 is present in a state in which it is combined with iron and is in an ionic state. Potassium sulphate addition tank (62a) is provided to precipitate / remove the heavy metals by combining with the silver sulphate. The method of claim 1, The electrokinetic 70a and 80a are provided so that a plurality of positive electrode 70a surrounds the negative electrode 80a around one negative electrode 80a installed to intensively purify the contaminated soil. , This electrokinetic machine (70a) (80a) is connected to the power supply unit 90 via a wire 92, characterized in that the soil purification system using a electrokinetic device, characterized in that provided.