KR20110107996A - System using thermal desorption for treating contamination soil and method using thermal desorption for treating contamination - Google Patents

Abstract

A soil soil treatment system and a soil soil treatment system using thermal desorption that can extract heavy metal contaminants from soil soil using waste heat generated during thermal desorption are introduced. Among them, the contaminated soil treatment system includes a rotary kiln (100) for thermally desorbing contaminants from the contaminated soil, a cyclone (200) for separating and treating coarse dust from the contaminated gas generated from the rotary kiln (100), and a cyclone. The cleaning reactor 300 for cleaning the contaminated gas of 200, the heat exchanger 400 surrounding the cleaning reactor 300 to cool the contaminated gas passing through the internal space of the cleaning reactor 300, and the heat exchanger ( A heavy metal extraction reactor (500) and a cleaning reactor (300) that pass through the cleaning reactor (300) to extract heavy metal contaminants from the contaminated soil discharged from the rotary kiln (100) by inputting an extractant under a predetermined temperature using heat of (400) as a heat source. It is configured to include a bag filter 600 for removing fine dust from the polluted gas.

Description

SYSTEM USING THERMAL DESORPTION FOR TREATING CONTAMINATION SOIL AND METHOD USING THERMAL DESORPTION FOR TREATING CONTAMINATION}

The present invention relates to a contaminated soil treatment system and a contaminated soil treatment method using thermal desorption, and more particularly, to a contaminated soil treatment system using thermal desorption that can extract heavy metal contaminants from contaminated soil by recovering heat generated during the thermal desorption process. It relates to a contaminated soil treatment method.

Today's industry has developed almost on the basis of fossil fuels, but the environmental pollution that accompanies the development of the industry is a serious problem that threatens human life.

Environmental pollution can be classified into air pollution, water pollution, and soil pollution, among which soil pollution not only causes water pollution through groundwater pollution, but also poses a serious threat to food production.

In particular, there is a growing interest in techniques for effectively purifying contaminated soil in a short time, since once the soil is contaminated, it takes a considerable period of time for the contaminated soil to be naturally purified.

Thermal desorption treatment method is a representative technique of the physical treatment method of the technology to purify the contaminated soil. The thermal desorption treatment method has a lower processing temperature than the incineration method, which is a conventional thermal treatment method, which consumes less energy and physically separates contaminants while maintaining the physical properties of the soil. It has the advantage of being filled.

There are many types of thermal desorption treatment devices, but cylindrical rotary kilns are frequently used. The rotary kiln is a cylindrical kiln, which is supported by a roller and is inclined at a predetermined angle, and is configured to rotate slowly.

In other words, when the soil contaminated into the rotary kiln is continuously supplied, the soil moves by sliding down the inner wall of the cylinder by the rotation of the rotary kiln, wherein the pollutants of the contaminated soil are mounted on the rotary kiln. Due to the heat supplied by the burners, it changes from the liquid / solid phase to the gas phase, resulting in thermal desorption which separates from the soil particles.

However, in the case of the conventional thermal desorption treatment method using a rotary kiln, the thermal energy used to thermally desorb the contaminants in the soil is not recycled and wasted as it is, and effectively purifies the fine dust and heavy metal contaminants from the gas generated in the rotary kiln. There was a problem that can not.

An object of the present invention for solving this problem, by using the heat desorption of volatile contaminants in the contaminated soil, by using the waste heat generated during thermal desorption using heat desorption to extract the heavy metal contaminants, which are non-volatile contaminants from the contaminated soil To provide a contaminated soil treatment system and a contaminated soil treatment method.

Contaminated soil treatment system according to the present invention to achieve the above object includes a rotary kiln, cyclone, cleaning reactor, heat exchanger, heavy metal extraction reactor and filter dust collector, the rotary kiln thermal desorption of contaminants from the contaminated soil, The clone separates and processes coarse dust from the polluted gas generated in the rotary kiln, the cleaning reactor cleans the polluting gas of the cyclone, and the heat exchanger cleans the polluting gas passing through the internal space of the cleaning reactor. Surrounding the reactor, the heavy metal extraction reactor is to extract the heavy metal contaminants from the contaminated soil discharged from the rotary kiln by inputting an extractant at a predetermined temperature using the heat of the heat exchanger as a heat source, and the bag filter is passed through the cleaning reactor It is characterized by removing the fine dust from the polluted gas.

At this time, the cyclone is further connected between the scrubber and the washing reactor, the thermal oxidizer further heats the polluting gas of the cyclone, and is connected between the heat exchanger and heavy metal extraction reactor to superheat the process water of the heat exchanger It further comprises a superheated steam generator for supplying the heavy metal extraction reactor as a heat source, and may further include a water jacket for cooling by spraying a cooling water to the contaminated soil discharged from the rotary kiln.

In particular, the water jacket is a water jacket case having a water jacket inlet and a water jacket discharge port through which the contaminated soil discharged from the rotary kiln is introduced, a cooling pipe installed inside the water jacket case, and spaced apart from the cooling pipe It is preferably composed of a spray nozzle for injecting cooling water to the soil. The cleaning reactor includes a cleaning housing having a cleaning inlet port and a cleaning discharge port through which contaminant gas is introduced, and a cleaning spray nozzle disposed radially in the cleaning housing to inject a cleaning agent into the cleaning housing. It is preferable to include a dust box installed at a lower end of the housing and collecting dust and contaminants cleaned by the cleaning spray nozzle. The heavy metal extraction reactor preferably includes an extraction tank in which a process water flow path through which superheated steam of the superheat steam generator is introduced is formed, and an impeller installed on the extraction tank to stir the mixed water in the extraction tank. The heat exchanger is preferably composed of heat exchange pipes arranged in a zigzag shape in the vertical direction of the cleaning housing.

The contaminated soil treatment method using thermal desorption according to the present invention is a contaminated soil thermal desorption step of thermal desorption of contaminants from the contaminated soil, and a coarse dust treatment step of selecting and treating coarse dust from the contaminated gas generated during the thermal desorption process of contaminated soil, The cleaning and cooling step of cleaning the polluted gas treated with dust and cooling the polluted gas through heat exchange of process water, and extracting heavy metal contaminants from the thermally desorbed contaminated soil by inputting extractant under constant temperature using heat exchanged heat as heat source. Heavy metal extraction step of extraction.

In particular, such a contaminated soil treatment method may further include a thermal oxidation step of heating and oxidizing the contaminated gas treated with the coarse dust after the coarse dust treatment step, and after the washing and cooling step, fine particles from the cooled contaminated gas The method may further include a filter dust collecting step of removing dust, and after the washing and cooling step, further include a superheated steaming step of superheating and vaporizing the heat-exchanged process water of the process water to the heat source of the heavy metal extraction step. Can be.

According to the present invention, the following remarkable effects can be realized.

First, the present invention can organically combine the rotary kiln and heavy metal extraction reactor, it is possible to solve the problem of treatment of heavy metal pollutants including arsenic which is volatile contaminants through the rotary kiln, as well as non-volatile contaminants through the heavy metal extraction reactor. There is this. As a result, there is an advantage that the contaminated soil can be treated very economically and efficiently regardless of the soil pollution source.

Second, the present invention by recycling the waste heat generated during the thermal desorption of the rotary kiln as a heat source of the heavy metal extraction reactor, to reduce the energy cost required for the use of heavy metal extraction reactor, while reducing the amount of extractant used in the heavy metal extraction reactor, extraction efficiency There is an advantage that can be greatly improved.

Third, the present invention provides a water jacket on the contaminated soil discharge outlet side of the rotary kiln, thereby removing the scattering dust from the thermally desorbed contaminated soil and preventing damage due to the high temperature gas generated from the thermally desorbed contaminated soil. have.

1 is a block diagram showing a contaminated soil treatment system using thermal desorption according to the present invention.
Figure 2 is a block diagram showing a water jacket of a contaminated soil treatment system according to the present invention.
Figure 3a is a block diagram showing a cleaning reactor of the contaminated soil treatment system according to the present invention.
FIG. 3B is a sectional view taken along the line “AA” of FIG. 3A;
Figure 4a is a block diagram showing a heavy metal extraction reactor of the contaminated soil treatment system according to the present invention.
4B is a plan view of FIG. 4A seen from above.
Figure 5 is a block diagram showing a bag filter of the soil treatment system according to the present invention.
Figure 6 is a schematic block diagram showing a soil treatment method according to the present invention.

First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in Figure 1, the contaminated soil treatment system according to the present invention, by thermal desorption of the contaminated soil (hereinafter contaminated soil) to treat volatile contaminants, remaining in the contaminated soil using heat generated in the thermal desorption process The biggest feature is the ability to remove non-volatile contaminants.

To implement this, the contaminated soil treatment system device is a rotary kiln (100), cyclone (200), thermal oxidizer (700), washing reactor (300), heat exchanger (400), superheated steam generator (900), heavy metals. It is configured to include an extraction reactor 500 and a bag filter 600.

The rotary kiln 100 is configured to thermally desorb the contaminants present in soil pores or between soil particles by applying thermal energy to the contaminated soil, and mainly volatile organic contaminants or oil contaminants are the main treatment targets. . At this time, the heat treatment for the contaminated soil in the rotary kiln 100 can convert heavy metals such as arsenic from reducible type to exchangeable type and soluble type, and heavy metals such as arsenic converted to exchangeable type and soluble type are heavy metals. Heavy metals can be easily removed through a low temperature extraction process through the extraction reactor 500.

For example, in the prior art, volatile organic pollutants or oil pollutants were mainly treated from contaminated soil using only the rotary kiln 100. However, in the present invention, the heat of the rotary kiln 100 and the rotary kiln 100 is removed. Through the heavy metal extraction reactor 500 used, not only the treatment of volatile organic contaminants and oil contaminants, but also the treatment of non-volatile contaminants such as heavy metal contaminants such as arsenic, lead, and mercury.

The rotary kiln 100 is fed with contaminated soil having a particle size of less than gravel through the input hopper 910 and the quantitative conveying conveyor 920. In this embodiment, contaminated soil having a particle size of 20 mm or less is used. The amount of contaminated soil is determined by the conveying speed of the fixed quantity conveying conveyor 920. At this time, by appropriately adjusting the conveying speed of the fixed quantity conveying conveyor 920 and the rotational speed of the rotary kiln 100, the contaminated soil according to the contaminated soil input amount Make sure the process is done smoothly.

The rotary kiln 100 is a rotating drum 110 is rotatably installed, an inverter (not shown) for controlling the rotational speed of the rotating drum 110, and is installed on one side of the rotating drum 110 contaminated soil It consists largely of a rotary kiln burner 120 to directly heat. Rotating drum 110 is installed to be inclined at an angle for smooth movement of the contaminated soil is provided with a guide wing (not shown) on the inner side. The rotating drum 110 is provided with a contaminated soil inlet 111 into which contaminated soil is introduced, a gas outlet 113 through which contaminated gas is evaporated from the contaminated soil, and a contaminated soil outlet through which the desorbed contaminated soil is discharged. do.

That is, when the contaminated soil is introduced into the rotary kiln 100 through the contaminated soil inlet 111, the contaminated soil discharge port of the rotating drum 110 by the guide action of the guide blade according to the rotation of the rotating drum 110 ( 112), at this time, the thermal desorption of the pollutant is made in the contaminated soil by the heating action of the rotary kiln burner 120. As a result, the contaminated gas thermally desorbed from the contaminated soil is discharged through the gas discharge port 113 and introduced into the cyclone 200, and the thermally desorbed contaminated soil is discharged through the contaminated soil discharge port 112 and introduced into the water jacket 800. do.

The water jacket 800 is installed at the contaminated soil discharge port 112 side of the rotary kiln 100. The water jacket 800 sprays cooling water on the contaminated soil discharged from the rotary kiln 100 so that the contaminated soil is cooled below a predetermined temperature. This is to prevent the scattering of contaminants, the generation of high temperature gas, or the damage of peripheral devices when the hot soil is discharged to the outside.

As shown in FIG. 2, the water jacket 800 has a water jacket case 810 having a water jacket inlet 811 and a water jacket outlet 812, and is arranged in a zigzag form within the water jacket case 810. The cooling pipe 820 and a plurality of cooling water spray nozzles 830 are spaced apart from the cooling pipe 820 so as to spray the cooling water to the contaminated soil. Therefore, when the contaminated soil is introduced into the water jacket case 810 through the water jacket inlet 811, the cooling water moving through the cooling pipe 820 is sprayed through the cooling water spray nozzle 830 and the contaminated soil is below a predetermined temperature. Allow it to cool down.

The cyclone 200 is installed at the gas outlet 113 side of the rotary kiln 100. The cyclone 200 separates and processes coarse dust from the polluting gas generated in the rotary kiln 100. For example, the cyclone 200 separates and treats the coarse dust visible by the centrifugal force and the force of gravity from the polluting gas, and moves the remaining polluting gas including the fine dust to the thermal oxidizer 700.

The thermal oxidizer 700 oxidizes and contaminates pollutants in the pollutant gas by heating the pollutant gas of the cyclone 200 heated first in the rotary kiln 100. The thermal oxidizer 700 includes a thermal oxidation burner 730 for thermally oxidizing the introduced polluted gas, a thermal oxidation inlet 710 through which the polluted gas of the cyclone 200 is introduced, and an oxidized polluted gas is discharged. It comprises a thermal oxidation outlet (720).

As shown in FIGS. 3A and 3B, the pollutant gas thermally oxidized in the thermal oxidizer 700 is introduced into the washing reactor 300. The cleaning reactor 300 cleans by spraying a cleaning agent such as NaOH on the gaseous pollutant gas. The cleaning reactor 300 is provided with a cleaning inlet 311 and a cleaning outlet 312 through which contaminant gas is discharged, and a cleaning housing 310 provided at upper and lower portions thereof, and radially disposed in the cleaning housing 310. Cleaning spray nozzle 320 for cleaning the dust and contaminants in the contaminated gas by spraying the cleaning agent inside the dust and contaminants are installed at the lower end of the cleaning housing 310 and cleaned by the cleaning spray nozzle 320 The dust box 330 is collected. Dust and contaminants collected in the dust box 330 are periodically discharged to the outside.

In the present embodiment, a process in which the polluted gas discharged from the cyclone 200 is continuously introduced into the thermal oxidizer 700 and the cleaning reactor 300 is used to oxidize and clean the polluted gas, but the cyclone 200 The polluted gas discharged from may be designed to be selectively added to the thermal oxidizer 700 or the cleaning reactor 300.

The cleaning reactor 300 is provided with a heat exchanger 400 for recovering and cooling the heat of the polluted gas heated by the rotary kiln 100 and the oxidation reactor. The heat exchanger 400 is configured in the form of a heat exchange pipe surrounding the cleaning reactor 300 to cool the contaminated gas passing through the internal space of the cleaning reactor 300. The heat exchange pipe is a structure in which high temperature process water is discharged through heat exchange with the cleaning reactor 300 by inputting low temperature process water, and the vertical direction of the cleaning housing 310 is increased so that the contact area with the cleaning housing 310 is increased. By being arranged in a zigzag form, the heat exchange with the cleaning reactor 300 is to be made efficiently.

The high temperature process water discharged from the heat exchanger 400 may be converted into a high pressure steam form through the superheated steam generator 900. The superheated steam generator 900 is connected between the heat exchanger 400 and the heavy metal extraction reactor 500, and serves to supply a heat source to the heavy metal extraction reactor 500 by superheating and steaming the process water of the heat exchanger 400. do.

The superheated steam generator 900 is composed of a cylindrical metal housing, the inside of the housing is provided with a large amount of cylindrical metal tube including a heating wire, steam input line and superheated steam discharge line and control panel It consists of. The superheated steam generator 900 recovers the waste heat generated during thermal desorption from the washing reactor 300 and controls the temperature of the heavy metal extraction reactor 500. That is, the superheated steam generator 900 condenses the high-temperature process water heat-exchanged in the washing reactor 300 at high pressure and supplies the heavy metal extraction reactor 500 in the form of high pressure steam, thereby raising the temperature of the extract liquid, It is possible to use the extract and induce a sufficient purification efficiency even with a short reaction time.

As shown in Figure 4a and 4b, the heavy metal extraction reactor 500 is a structure for extracting heavy metal contaminants from the contaminated soil discharged from the rotary kiln 100 by inputting the extractant, The extraction tank 510 is filled, the extraction inlet 511 and the extraction outlet 512 provided on one side and the other side of the extraction tank 510, and the chemical reaction between the desorption soil and extractant heat-desorbed smoothly It is configured to include an impeller 530 installed on the top of the extraction tank 510 to generate sufficient agitation, and a drive motor 540 for driving the impeller 530. At this time, the extraction tank 510 is formed with a superheated steam flow path (not shown) in which the superheated steam of the superheated steam generator 900 is introduced, the temperature in the heavy metal extraction reactor 500 is a temperature for the effective extraction of heavy metal contaminants ( About 105 °). In addition, the contaminants extracted by the extraction liquid is discharged through the waste liquid outlet 513 of the extraction tank 510, the discharged pollutants are moved to the extraction liquid treatment tank 560 and processed.

Extracts are used to extract heavy metal contaminants from the contaminated soil discharged from the rotary kiln (100) through chemical oxidation / reduction reactions, and the types of contaminated heavy metals (arsenic, lead, mercury ...) in the contaminated soil. Depending on the optimum extract that can be reacted with these heavy metals can be used. For example, when arsenic heavy metals are mainly contained in contaminated soil, NaOH reacted with arsenic may be mainly used.

Meanwhile, as shown in FIG. 5, the bag filter 600 electromagnetically collects the fine dust in the polluted gas that has passed through the cleaning reactor 300 to satisfy the air pollution purification standard. The filter dust collector 600 is a filter case 610 to form an upflow gradient, the filter inlet 611 and the filter outlet 612 provided in the filter case 610, and to filter the polluting gas including fine dust Electromagnetic pulse 630 for periodically separating the fine dust adsorbed on the surface of the filter dust collecting plate 620 by applying a plurality of filter dust collecting plate 620, the filter dust collecting plate 620 and the filter dust collecting plate 620 It consists of a dust box 640 to collect and process the fine dust separated from. That is, when the pollutant gas including the fine dust is introduced into the filter inlet 611 of the filter dust collector 600, the pollutant gas including the fine dust passes through the plurality of filter dust collecting plate 620 and then discharged through the filter outlet 612. Then, it is discharged to the outside through the stack 960.

At the inlet / outlet of the rotary kiln 100, the thermal oxidizer 700, and the bag filter 600, a heat sensor (not shown) for temperature sensing may be provided, respectively. In consideration of this, it is desirable to make the overall adjustment of the system smooth. The dust accumulated in the cyclone, the thermal oxidizer 700, the washing reactor 300, and the bag filter 600 is collected in a dust storage tank (not shown) through the dust feeder 950. The pollutant gas is transferred to the cyclone, the thermal oxidizer 700, the washing reactor 300, and the bag filter 600 through the blower fan 930.

Referring to the contaminated soil treatment method of the present invention made of such a configuration as follows.

As shown in Figure 6, the contaminated soil treatment method according to the present invention, the contaminated soil thermal desorption step, coarse dust treatment step, thermal oxidation step, washing and cooling step, superheated vaporization step, heavy metal extraction step and filter dust collection step Include.

First, before the contaminated soil thermal desorption step, contaminated soil having a particle size of 20 mm or less is introduced into the rotary kiln 100 through the input hopper 910 and the quantitative conveying conveyor 920. At this time, it is assumed that the contaminated soil introduced into the rotary kiln 100 includes not only volatile organic contaminants and oil contaminants but also nonvolatile contaminants.

The contaminated soil thermal desorption step thermally desorbs contaminants from the contaminated soil introduced into the rotary kiln 100. That is, when the contaminated soil is introduced into the rotary kiln 100, the oxidation of the rotary kiln burner 120 of the rotary kiln 100 is performed, and the contaminated soil is thermally desorbed from the contaminated soil. The same heavy metal is converted from the reducible type to the exchangeable type and the soluble type. Thermally desorbed contaminated soil is discharged from the rotary kiln 100 is cooled through the cooling water, and the contaminated gas generated during thermal desorption is treated by coarse dust in the coarse dust treatment step.

Coarse dust treatment step is to treat the coarse dust from the polluted gas generated in the contaminated soil thermal desorption step. At this time, the selection of coarse dust from the polluted gas using the centrifugal force and gravity of the cyclone 200, the remaining polluted gas other than coarse dust is oxidized in the thermal oxidation step.

In the thermal oxidation step, coarse dust is treated and the remaining pollutant gas is heated and oxidized. That is, by heating the pollutant gas primarily heated in the rotary kiln 100 to burn the pollutants in the polluted gas. The secondary heated pollutant gas is cleaned and cooled in the washing and cooling step.

The washing and cooling step cleans the contaminated gas treated with the coarse dust and cools the contaminated gas through heat exchange of process water. The cleaning of the contaminated gas is performed through a cleaning agent injected from the cleaning spray nozzle 320 of the cleaning reactor 300, and the cooling of the contaminating gas is performed by the heat exchanger 400 surrounding the cleaning reactor 300. Heat exchanged in the heat exchanger 400 is converted to superheated steam in the superheated steaming step.

The superheated steaming step superheats and vaporizes the process water heat exchanged in the washing and cooling step and supplies it to the heat source of the heavy metal extraction step. Through this, the recovered heat obtained through heat exchange in the washing and cooling steps is used as a heat source for heavy metal extraction.

The heavy metal extraction step maintains a temperature at which an effective extraction can be made using the heat source supplied to the superheated steaming step. Therefore, when the extractant is added under a temperature heated to a constant temperature, heavy metal contaminants can be effectively extracted from the contaminated soil desorption in the contaminated soil thermal desorption step.

On the other hand, after the cleaning and cooling step, the contaminated gas cooled by the heat exchanger 400 is removed fine dust through the filter dust collecting step. The filter dust collecting step allows the contaminated gas cooled in the washing and cooling step to pass through the plurality of filter dust collecting plates 620 so that the fine dust contained in the polluting gas is filtered.

As described above, the present invention, according to the present form of heavy metal contaminants such as arsenic in thermal desorption of the contaminated soil, converts to the form of heavy metal contaminants capable of thermal desorption and low temperature extraction, and the waste heat recovered from the heat exchanger 400 By supplying the heat source of the heavy metal extraction reactor 500 will increase the extraction efficiency of arsenic and other heavy metals, it is possible to reduce the energy costs required to clean up the soil pollution.

Although the present invention has been described in detail using the preferred embodiments, the scope of the present invention is not limited to the specific embodiments, and should be interpreted by the appended claims. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

100: rotary kiln 200: cyclone
300: washing reactor 400: heat exchanger
500: heavy metal extraction reactor 600: filtration precipitator
700: thermal oxidizer 800: water jacket
900: superheated steam generator

Claims (11)

Rotary kiln (100) for thermal desorption of contaminants from contaminated soil;
A cyclone (200) for separating and treating coarse dust from the polluting gas generated in the rotary kiln (100);
A cleaning reactor (300) for cleaning the polluted gas of the cyclone (200);
A heat exchanger (400) surrounding the cleaning reactor (300) to cool the pollutant gas passing through the internal space of the cleaning reactor (300);
A heavy metal extraction reactor (500) for extracting heavy metal contaminants from the contaminated soil discharged from the rotary kiln (100) by introducing an extractant under a predetermined temperature using the heat of the heat exchanger (400) as a heat source; And
The soil contaminated soil treatment system using a thermal desorption comprising a; dust collector 600 for removing fine dust from the contaminated gas passed through the cleaning reactor (300). The method according to claim 1,
And a thermal oxidizer (700) connected between the cyclone (200) and the cleaning reactor (300) to heat second the pollutant gas of the cyclone. The method according to claim 1,
A superheated steam generator 900 connected between the heat exchanger 400 and the heavy metal extraction reactor 500 to superheat and vaporize the process water of the heat exchanger 400 to supply the heavy metal extraction reactor 500 as a heat source. Soil treatment system using thermal desorption, characterized in that it further comprises. The method according to claim 1,
Further comprising a water jacket 800 for cooling by spraying cooling water on the contaminated soil discharged from the rotary kiln 100,
The water jacket 800 includes a water jacket case 810 having a water jacket inlet 811 and a water jacket outlet 812 through which the contaminated soil discharged from the rotary kiln 100 is discharged and the water jacket case 810. ) Contaminated soil treatment system using thermal desorption, characterized in that the cooling pipe 820 is installed inside, and the cooling water spray nozzle 830 disposed to be spaced apart from the cooling pipe 820 to spray the coolant to the contaminated soil. . The method according to claim 1,
The cleaning reactor 300 includes a cleaning housing 310 in which the cleaning inlet 311 and the cleaning discharge port 312 through which the pollutant gas is introduced are respectively provided at upper and lower portions thereof;
A cleaning spray nozzle 320 disposed radially in the cleaning housing 310 to inject a cleaning agent into the cleaning housing 310;
The soil soil treatment system using thermal desorption, characterized in that it comprises a dust box 330 which is installed at the lower end of the cleaning housing 310 is collected by the cleaning spray nozzle 320 and the dust and pollutants. The method according to claim 3,
The heavy metal extraction reactor 500 is installed in the extraction tank 510 and the upper part of the extraction tank 510, the extraction tank 510 is formed a process flow path through which the superheated steam of the superheated steam generator 900 is introduced. Polluted soil treatment system using thermal desorption, characterized in that it comprises an impeller (530) for stirring the mixed water. The method according to claim 5,
The heat exchanger 400 is a contaminated soil treatment system using thermal desorption, characterized in that the heat exchange pipe is arranged in a zigzag form in the vertical direction of the cleaning housing (310). A thermal soil desorption step of thermally desorbing contaminants from the soil;
A coarse dust treatment step of selecting and treating coarse dust from the polluted gas generated during the thermal desorption process of the contaminated soil;
A washing and cooling step of washing the contaminated gas treated with coarse dust and cooling the contaminated gas through heat exchange of process water; And
And a heavy metal extraction step of extracting heavy metal contaminants from the thermally desorbed contaminated soil by inputting an extractant under a predetermined temperature using heat exchanged heat as a heat source. The method according to claim 8,
After the coarse dust treatment step, the contaminated soil treatment method using thermal desorption, characterized in that it further comprises a thermal oxidation step of heating and oxidizing the contaminated gas treated with coarse dust. The method according to claim 8,
After the cleaning and cooling step, the contaminated soil treatment method using thermal desorption, characterized in that it further comprises a filter dust collection step for removing fine dust from the cooled polluted gas. The method according to claim 8,
After the washing and cooling step, the contaminated soil treatment method using a thermal desorption step further comprises the superheated vaporization step of supplying the heat-exchanged process water to the heat source of the heavy metal extraction step.

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