KR20170046501A

KR20170046501A - Apparatus for purify soil polluted crude using activator and air

Info

Publication number: KR20170046501A
Application number: KR1020150146928A
Authority: KR
Inventors: 신동춘; 김종원; 박준형; 정문영
Original assignee: 벽산엔지니어링주식회사
Priority date: 2015-10-21
Filing date: 2015-10-21
Publication date: 2017-05-02
Also published as: KR101791447B1

Abstract

The present invention relates to a facility and method for purification of crude oil contaminated soil using interfacial activation and air, which effectively removes crude oil contaminants from soil contaminated with crude oil (mineral oil extracted from oil wells) through surfactants, solvents and pre- And to prevent environmental pollution caused by crude oil pollutants.
The present invention relates to a surfactant-containing surfactant-supplying tank for storing surfactant and supplying the surfactant; A methanol feed tank in which methanol is stored and methanol is supplied; A water supply tank for storing water and supplying the water; The surfactant is supplied from the water supply tank and the surfactant from the surfactant supply tank and the contaminated soil is crushed to a particle size of 1 mm or less or 0.5 mm or less, A wet scrubber for inducing interface activation; A desalting tank for receiving contaminated soil from the wet scrubber, water from the water supply tank and desorbing crude oil contaminants from the soil; A stirring tank for receiving a mixture of the contaminated soil and water from the desalting tank and supplying and stirring methanol from the methanol feeding tank; A float sorting tank for sorting the soil and crude oil contaminants passing through the stirring tank by specific gravity so that crude oil contaminants are separated from the soil and floated to the water surface through air injection by an air injector; A soil dehydrator for dehydrating the soil recovered through sedimentation in the floating sorting tank; And a crude oil pollutant dewatering unit for dewatering the suspended matter recovered through floating in the floating sorting tank.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method and apparatus for purifying soil contaminated with crude oil,

The present invention relates to a purification facility and method for contaminated soil contaminated with crude oil, and more particularly, to a method and apparatus for recovering soil contaminated with crude oil (unprocessed oil as a mixture of hydrocarbons extracted from underground oil wells) The present invention relates to a crude oil contaminated soil purification facility and method.

Since 1990, social interest in soil and groundwater pollution has increased in Korea, and the Soil Conservation Act of Korea has been financed in 1995 and the basic plan for groundwater conservation has been established. .

In the case of foreign countries, about 20% of the oil storage facilities are reported to be polluting the soil and groundwater due to oil spillage, and the soil pollution inducing facilities in Korea are returned due to the recent return of the US bases. There are many oil-related facilities such as areas, industrial zones, military areas with oil facilities, and gas stations, and there is considerable pollution due to aged facilities, careless handling, leakage from oil pipelines, And soil pollution can cause secondary pollution such as groundwater pollution and spread to neighboring areas, adding toxicity to the environment and making purification more complicated and difficult. Contaminated oil in the soil is naturally purified by physical, chemical and biological mechanisms in the natural state, but it has a low purification rate due to its low throughput and causes problems such as destruction of ecosystem and secondary pollution during the purification period. .

Purification techniques in contaminated sites are developed in various forms and applied to the site. Depending on the medium to be treated, soil treatment technology and groundwater treatment technology, or unsaturated versus treatment technique and saturation treatment technique can be distinguished. Depending on the nature of the pollutant and site characteristics, the technology may be applied as a single technology, or a combination of technologies may be used in combination . The domestic contaminated soil clean - up market is an emerging market with a very short history and a small market size. Therefore, since there is no systematic management and information collection on contaminated sites and contaminated soil remediation technologies, statistical data such as the status of domestic polluted sites and the application of contaminated soil remediation technologies are not yet available.

Conventionally, various kinds of oil pollutants have been purified, but crude oil (oil extracted from oil wells, hydrocarbon as main component is mixed with a lot of impurities, which is different depending on the place where the oil is produced) Contamination of polluted soil is extremely small and causes enormous environmental damage especially in the event of a large oil tanker collision, a stranded oil, a crude oil storage tank, or a leakage of a large amount of oil (crude oil)

In case of pollutants, there is a high viscosity and little volatility. Therefore, it is difficult to purify by conventional soil remediation method, and it is possible to purify by thermal treatment method, but it is disadvantageous in that it is costly.

For example, Korea's oil pollution sources are relatively volatile and relatively decomposable, such as gasoline, kerosene, light oil, etc., and the total concentration of petroleum hydrocarbons (TPH) is not so high. At present, Korean soil cleaners are purifying by using soil microbial cultivation method when the concentrations of these oil pollutants are low and soil washing or thermal desorption methods using surfactants when they are high concentration.

However, the oil pollutants in crude oil contaminated soils of Kuwait are mostly volatile substances with little volatile components and most of them are oil pollutants with high concentration (TPH concentration of 50,000 mg / kg or more) It is difficult to purify only by law or soil cultivation.

On the other hand, the thermal treatment method can purify crude oil contaminated soil, but it has a disadvantage that it requires a lot of processing cost and discharges toxic air pollutants such as polycyclic aromatic hydrocarbons (PAHs) and a large amount of greenhouse gas (CO ₂ ).

Patent Document (Registered Patent No. 10-1200485) discloses a group separation step of crushing mined ore mined in a mine to remove a target mineral; A sludge pulping step of mixing the minerals separated in the unit separation step with water to form a sludge pulp; A sub-pre-emulsion mixing step of mixing a pre-emulsion with the formed suture pulp; A reciprocating moving step of reciprocating the barbed minerals between the barge vessels in accordance with the pre-preg mixing; And a discharging step of discharging the flotated minerals when the flotation of the flotation pulp after the reciprocating movement is not less than 3%, the flotation method is only for the flotation by the flotation agent and can not purify the oil contaminated soil .

Patent No. 10-1200485

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a method and apparatus for recovering crude oil pollutants from crude oil (mineral oil as extracted from oil wells) The purpose is to provide.

The present invention relates to a surfactant-containing surfactant-supplying tank for storing surfactant and supplying the surfactant; A methanol feed tank in which methanol is stored and methanol is supplied; A water supply tank for storing water and supplying the water; A surfactant is supplied from the water supply tank, water is supplied from the water supply tank, the surfactant is supplied from the surfactant supply tank, and the contaminated soil is crushed to a particle size of 1 mm or less than 0.5 mm, while interfacial activation of the contaminant through the surfactant A wet shredding machine for inducing the water; A desulfurizing tank for removing contaminated material from the soil by supplying hot water from the water supply tank (hot water supply of 40 ° C or higher) to the contaminated soil from the wet shredder; A chemical agitator for completely separating the desorbed contaminants from the soil by supplying and stirring a mixture of the contaminants separated from the turbines and the soil and water; A float sorting tank for sorting the soil having passed through the stirring tank and the desorbed contaminants by air; A soil dehydrator for dehydrating the soil selected (sedimented) through float sorting in the floating sorting tank; And a pollutant dehydrator for dehydrating the suspended matters (desorbed pollutants) collected through floating in the floating sorting tank.

According to the interfacial activation and air purification method of the present invention, the crude oil is melted using a solvent mainly composed of hydrocarbon in a state in which the separation of the crude oil contaminant is induced through the surfactant and high temperature water supply It has the effect of maximizing the recovery rate of pollutants and producing high-quality purified soil by separating the water from the surface by lowering the viscosity and being submerged in the air and being submerged in water And it is possible to prevent the contamination due to the chemicals because the noxious agent used in the prior art is not used (only a very small amount of noxious agent is used).

Compared with the barge method using only the preheating agent, the prior art can not separate the crude oil from the soil, whereas the present invention maximizes the purification rate of the oil contaminated soil by separating and recovering most pollutants into the soil, It has the effect of preserving the environment and ecosystem through the prevention of the contamination. It is possible to purify the contaminated soil through only the mixing of the solvents and the mixture of the solvent. Therefore, it also has the effect of drastically reducing the investment cost and maintenance cost. .

In addition, there is also an effect of reducing the cost of soil purification by recovering and reusing the solvent used for the purification of contaminated soil.

FIG. 1 is a conceptual view of a clean-up facility for contaminated crude oil using interfacial activation and air of the present invention. FIG.

As shown in FIG. 1, the crude oil contaminated soil purifying facility according to the present invention is a facility for purifying crude oil contaminated soil (hereinafter referred to as " contaminated soil ") and crude oil contaminated material (Hereinafter referred to as "medicament") is uniformly stirred and mixed by a desorbing tank 10, a stirring tank 20 and a stirring tank 20 for separating contaminants from each other into precipitates and suspensions A soil dehydrator 40 for dehydrating the sediment recovered and recovered after floatation by the floating sorting tank 30 and a floating sorting tank 30 for recovering the purified soil and a float recovered in the floating sorting tank 30, A dehydrating pollutant dehydrator 50, and a surfactant feed tank 60 and a methanol feed tank 70 for the purification of contaminated soil.

It is preferable that the magnetic separator 1, the particle size separator 2, and the wet scrubber 3 are further included to increase the purification rate of the contaminated soil.

The contaminated soil is not subjected to particle size selection and contains various particle sizes and iron contents. The magnetic separator (1) adsorbs and separates foreign matter of iron components contained in contaminated soil by magnetic force.

The particle sizer (2) is a large particle, which is selected on the basis of a particle size of 50 mm, so that soil having a particle size of 50 mm or more is supplied separately and contaminated soil having a particle size of 50 mm or less is supplied to the wet shredder (3).

The wet shredder (3) is a water tank filled with water, and is configured to sort the particles after the contaminated soil is removed in water. The contaminated soil having a particle size of 50 mm or less supplied from the particle size separator (2) Then, the contaminated soil below the reference particle size is supplied to the desorbing tank (10) while the soil above the reference particle size is supplied separately so that the soil can be treated separately. In this process, So that the contaminant removal efficiency by the solvent can be improved.

(3) Before the wet shredder (3), there is no significant difference in the purification rate depending on the amount of contaminated soil as an auxiliary process for increasing the purification efficiency of the pollutant. However, since the wet shredding process, And thus the amount of water, contaminated soil and surfactant is supplied to the wet scrubber 3 in a quantitative manner for purification.

700 to 750 liters of water and 2 to 3 kg of surfactant are used for 1,000 kg of contaminated soil.

The surfactant supply tank (60) stores the surfactant therein, pumps the surfactant through a pump or the like, and supplies the surfactant to the wet scrubber (3) through a supply pipe. The supply pipe is provided with a flow meter for detecting the supply amount of the surfactant and a valve for regulating the opening degree. The pump is controlled in operation through the control of the controller so that the surfactant, which is set by the manager, .

The surfactant is preferably sodium lauryl sulfate and weakens the bond between the contaminant and the soil so that the contaminant can be easily removed from the soil in a subsequent process, and 2.4 kg is mixed with 1,000 kg of the contaminated soil.

The surfactant supply tank 60 is operated together with the water supply tank 61. After the water is supplied from the water supply tank 61, the surfactant supply tank 60 mixes the water and the surface active agent and supplies them to the wet scrubber 3 do.

(Preferably 2.4 kg of powder and 720 liters of water) in a liquefaction tank (liquefied by mixing water and powder with an installed stirrer) capable of separately hydrating the powdery sodium laurylsulfate.

The water (high-temperature) supply tank 61 is in the form of a tank for heating and storing water or water heated to a high temperature (40 ° C or more, 40 to 50 ° C) through a separate heater through a heater (electric heater or the like) And then supplies the water to the surfactant supply tank 60 through the supply pipe. Although the heater may be installed in the water supply tank 61, it may supply water at a temperature different from that supplied to the surfactant supply tank 60 at a location other than the surfactant supply tank 60, It is also possible to separately configure to supply the water of the proper temperature.

The desorbing tank 10 refers to water supplied from the water supply tank 61 to the desulfurization tank 10 from the water supply tank 61 while being supplied with the contaminated soil mixture from the wet scrubber 3 , High temperature 40 DEG C or higher, 40 to 45 DEG C].

The water supply tank (61) also supplies water to the wet shredder (3). That is, the water supply tank 61 supplies water to the wet scrubber 3 and the surfactant supply tank 60, respectively.

The mixing ratio (based on weight) of the contaminated soil and the process water in the desalination tank 10 is preferably the contaminated soil: water = 1: 3 to 9.

The desalination tank 10 is in the form of a tank or tank in which contaminants of the contaminated soil mixture can be removed from the soil.

The agitation tank 20 is supplied with the pollutants and the soil desorbed from the desalination tank 10 and supplies methanol as the solvent from the methanol feed tank 70 and the process water from the water feed tank 61 and stirs them. The mixing ratio is the contaminated soil: the number of steps: methanol = 1: 3 to 9: 0.00001 to 0.002 (weight ratio).

The agitating tank 20 is connected to the desalting tank 10 and the methanol feed tank 70 by pipelines or the like so as to be able to supply the respective materials from the respective tanks 10 and 70, And may be in the form of a stir bar together. The stirring rod is rotated at a constant stirring speed, for example, by a rotational force of a motor, so that the materials in the stirring tank 20 are stirred to separate all the contaminants in the contaminated soil. The stirring speed is preferably 300 to 1500 rpm and the stirring time is preferably 0.5 to 4 minutes.

Methanol can be stored in a feed tank 70 that can store and supply the stock solution.

The methanol supply tank 70 is, for example, a solvent tank), a solvent pump for pumping and supplying a solvent stored in the solvent tank, a solvent supply pipe for connecting the solvent tank and the agitation tank 20, And a solvent valve for regulating the opening of the solvent supply pipe. The solvent pump and the solvent valve are operated manually by the administrator to manually mix the solvent or automatically controlled by the controller to automatically mix the solvent. In the case of the latter automatic control system, the mixing amount of the solvent to the contaminated soil is built up through the database, and the controller automatically controls the mixing of the solvent through input or detection of the contaminated soil throughput.

The solvent can be ethanol or methanol, preferably ethanol or methanol, and is mixed at a rate of 0.1 to 2 kg per ton of contaminated soil, preferably 1 kg. When less than 0.1 kg is mixed, the amount of crude oil extracted is small, and when mixed more than 2 kg, there is no significant change in crude oil extraction amount.

Methanol and ethanol alcohols dissolve some of the crude oil to lower the bond strength with the soil particles, thereby easily dropping the crude oil from the contaminated soil. In particular, contaminants in contaminated soil are rapidly and cleanly removed through solvents such as methanol, since the binding force has already weakened through the surfactant.

Solvent can be made of hydrocarbon-based material. Since crude oil is the main component of hydrocarbon, solvent and crude oil react with each other and weaken the viscosity of crude oil so that crude oil is separated from soil when mixed with pigments. Alcohols, which are organic solvents, dissolve some of the crude oil from the soil by the principle of solvent extraction and lower the bond strength with the soil particles, so that the crude oil is removed from the soil particles while stirring process (soil washing process) Floating is selected in float sorting step.

A separate solvent replenishing tank and a methanol feed tank 70 can be operated together for smooth supply of the solvent. The solvent replenishing tank is a tank in which a solvent is stored. The pump is driven by sensing the level or the flow rate of the methanol feed tank 70 so that a predetermined amount of solvent is stored in the methanol feed tank 70. Of course, the replenishment of the solvent is also possible by the manual operation of the manager.

The water supply tank 61 can have the same configuration as the methanol supply tank 60 and includes a water tank, a water pump for pumping and supplying the water stored in the water tank, a water supply pipe 60 for connecting the water tank and the desorption tank 10, A water flow meter for detecting the amount of water supplied through the water supply pipe, and a water valve for regulating the opening of the water supply pipe. The water pump and the water valve are operated manually by an administrator to manually mix the water or automatically controlled by the controller to automatically mix the water. In the case of the latter automatic control system, a mixing amount of water for contaminated soil is built up through a database, and the controller automatically controls the mixing of water through input or detection of contaminated soil throughput.

It is possible to use a water replenishing tank together with the water supply tank 61 for smooth supply of water. The water replenishing tank replenishes water in the same manner as the solvent replenishing tank.

The desorption tank (10) and the stirring tank (20) may have independent structures, but they may be formed of one set, that is, mixing and stirring may be performed in one set.

The floating sorting tank 30 separates contaminants from the soil through the difference in specific gravity from the mixture supplied from the agitating tank 20 (a mixture of contaminated soil and solvent and process water).

The air injector 31 is applied to increase the efficiency of the specific gravity sorting in the floating sorting tank 30.

The air injector 31 injects an air amount of 1 to 10 times / min to the floating separator capacity into the floating sorting tank 30 so that relatively light contaminants can be quickly separated from the soil and floated to the surface of the water.

The present invention relates to a method for floating contaminants submerged in water below a water surface without using a catcher and a foaming agent used in the conventional flotation method. In the flotation screening tank (30) I will.

The air injector 31 generates air bubbles in the water inside the floating sorting tank 30 and preferably injects the air so that the pollutants are directed to the water surface. For example, the air injector 31 can circulate air from the bottom in the floating sorting tank 30 to one or more stages There are various methods such as a method in which a large number of oxygen nozzles are arranged to spray air toward the water surface, a method in which air nozzles are arranged in one or more stages along the inner wall of the floating sorting tank 30 to inject air toward the center Do.

The soil is sorted (settled) through the floating sorting tank (30) and the soil and the contaminants are separated by floating the contaminants.

The soil dehydrator 40 separates the solvent or crude oil components contained in the soil through solid separation by supplying and dehydrating the selected soil (sedimented soil) in the floating sorting tank 30, thereby recovering the purified soil of high purity and reusing the solvent And all the known dehydration methods are possible.

The recovered soil recovered through the soil dehydrator 40 can be reused for a variety of uses (such as agricultural land, grassland, or sanctuary landfill).

The pollutant dehydrator 50 separates the polluted minerals (separated from the solvent or the crude oil component) from the solvent or the crude oil component through solid separation by supplying and dehydrating the contaminants suspended in the floating separator 30 to reduce the amount of waste There is an effect of reusing the solvent, and all known dehydration methods are possible.

The polluted minerals recovered through the pollutant dehydrator (50) are treated by an incineration or waste treatment facility.

In addition, the present invention is applied to a water treatment system 80 for treating a liquid phase generated in the soil dehydrator 40 and the pollutant dehydrator 50.

The water treatment system 80 removes the crude oil component from the liquid material (solvent, crude oil component) recovered through the soil dehydrator 40 and the pollutant dehydrator 50, thereby recovering the solvent, thereby reducing the cost by reusing the solvent.

The water treatment system 80 comprises a distillation column for separating the solvent and the crude oil component, and a cooler for liquefying the solvent separated by the distillation column.

The distillation column receives the liquid material from the soil dehydrator 40 and the pollutant dehydrator 50 and vaporizes the solvent through heating.

Through the distillation tower, wastewater mixed with water and crude oil components is discharged, and the wastewater is purified by the purified water and then supplied to the water supply tank 61 for reuse.

The cooler is connected to the distillation tower through a pipe, and the vaporized solvent gas is liquefied in the distillation column to recover the liquid solvent.

The solvent recovered through the cooler may be supplied to the methanol feed tank 70 and reused.

The water treatment system 80 may optionally be used only to purify the water recovered through the soil / contaminant dehydrators 40, 50 without solvent recovery.

A method for purifying crude oil contaminated soil according to the present invention will be described.

1. Selecting magnetic force.

In order to remove the iron component contained in the contaminated soil, the contaminated soil is supplied to a magnetic separator. For example, a magnetic separator (1) is installed on a conveyor belt and the magnetic force of the magnetic separator To remove the iron component.

2. Grain selection.

The contaminated soil has various particle sizes, especially large particles (for example, 50 mm or more) and these particles can be treated separately, so that they are sorted through the particle size separator 2.

3. Wet shredding.

The contaminated soil having a particle size of 50 mm or less through the particle size separator (2) is supplied to the wet scrubber (3). The wet scrubber 3 is filled with water through a water supply tank 61 and a surfactant is supplied through the surfactant supply tank 60.

The surfactant conditions inside the wet shredder (3) are 10 L of water and 0.025 g of surfactant in 15 kg of contaminated soil.

The wet shredder 3 crushes the contaminated soil of a particle size of 50 mm or less supplied from the particle size separator 2 to 1 mm or 0.5 mm or less and the surfactant activates the contaminants attached to the surface of the soil in the wet shredder 3 The binding force of the contaminants is weakened and the contaminants are separated.

4. Tally.

The contaminated soil that has undergone the previous process is introduced into the desalination tank 10 and the process water (40 ° C) of the proper amount (6 times of the contaminated soil) for the contaminated soil is supplied from the water supply tank 61, So that contaminants are removed from the soil.

5. Stirring.

A mixture of the desorbed contaminants, the soil and the process water in the desalination tank 10 is supplied to the agitating tank 20, and the methanol is introduced into the agitating tank 20.

After the addition of methanol, stir for 30 seconds to 2 minutes, and methanol will remove contaminants from the soil. A temperature of 25 to 40 ° C is maintained during the agitation.

6. Flotation screening.

The mixture of the contaminated soil and the process water after the stirring is supplied to the floating sorting tank (30), and the contaminants desorbed by the floating sorting are separated from the soil by floating completely. At this time, air is injected into the floating sorting tank (30) to help float the contaminants, thereby maximizing the efficiency of separating contaminants.

That is, both the soil and the pollutants are high in specific gravity and sink to the bottom, and the pollutants float to the surface by the air injected from the air injector (31).

More specifically, the pollutant has a specific gravity higher than 1 but is lower than the soil, so that it is immersed in the water between the water surface and the floor. The air injected from the air injector 31 generates air bubbles, adsorbs contaminants, Especially by the injection pressure of the air, the contaminants float to the surface more quickly.

On the other hand, some of the pollutants can not be separated from the soil but are weakly attached to the soil, and these contaminants are also removed from the soil by the air injected by the air injector 31 and floated to the water surface.

7. Soil dehydration.

Soil, which is selected (sediment) collected through separation process of floating separation, has water, solvent and liquid contaminant, and cleans soil by dehydration to recover purified soil. Soil dehydration is possible with all known dehydration methods and dehydration to a constant water content (30% ~ 40%, average value 35%) or less.

Soil dehydrated, cleaned soil is transported to the reservoir through separate shipping lines.

8. Suspension dehydration.

Suspended matter exists in the presence of particulate matter and liquid matter (water, solvent, etc.) and recycles waste (water content less than 15%) through dehydration.

9. Solvent recovery.

7. The dehydration process is derived from the soil dehydration process and the suspension dehydration process.

The dehydrated liquid is subjected to water treatment through the water treatment system 80, and pure water is supplied to the water supply tank 61 and reused.

Embodiments of the present invention of the present invention are as follows.

1. Preparation of contaminated soil.

Contaminated soil with a particle size of 1 mm or less (pollution concentration 39,200 mg / kg) was prepared.

2. Add surfactant.

100 g of contaminated soil, 0.24 g of surfactant, and 72 ml of water (based on weight).

3. Methanol mixing and stirring

0.1 g of methanol was added to 100 g of the contaminated soil, and the stirring time was set to 1 minute (temperature 40 캜).

4. Separation by floating precipitation.

Soil and suspended matter were separated by flocculation of contaminant soil mixture through pre - process and separated into contaminants (immersed in water) and sediments of soil (suspension time 10 minutes, temperature 40 ℃). At this time, the air amount was set to 3 times / min of the capacity of the floating sorting tank.

5. Soil dehydration.

The soil was dehydrated to recover the clarified soil.

The amount of purified soil was about 80 ~ 85% by weight (24 ~ 25.5g) and the contamination concentration was found to be 1,400 ~ 2,300 mg / kg.

6. Floating dehydration.

The amount of waste recovered was 15 ~ 20% (4.5 ~ 6g) and the contamination concentration was 91,850 ~ 12,3724 mg / kg.

7. Solvent recovery.

(The distillation conditions are 780 ° C. or higher and 5 to 20 minutes, and the distillation conditions can be changed), and then subjected to liquefaction (cooling conditions are -114 ° C. or lower, 20 minutes, and this cooling condition can be changed) to recover the liquid phase solvent. Solvent (over 30% of the input) was recovered through this process.

In addition, since the solvent vaporized through the distillation process, only the contaminated water remained, so the contaminated water (94 to 97%) was recovered and the contaminated water was treated to recover the purified water. As shown in Table 1, it was confirmed that the polluted soil was significantly lowered after the experiment.

Experiment No . Initial concentration PHC Concentration after experiment PHC Remarks Picture One experiment

39,200

2,300

Rehearsal experiment

2,200 After the one-time experiment,

1,400 1 time

1: magnetic separator, 2: particle size selector
3: wet shredder, 10: desalination tank
20: stirring tank, 30: floating sorting tank
40: soil dehydrator, 50: contaminant dehydrator
60: Surfactant supply tank, 61: Water supply tank
70: methanol feed tank, 90: water treatment system,

Claims

A surfactant supply tank for storing the surfactant and supplying the surfactant;
A methanol feed tank in which methanol is stored and methanol is supplied;
A water supply tank for storing water and supplying the water;
The surfactant is supplied from the water supply tank and the surfactant from the surfactant supply tank and the contaminated soil is crushed to a particle size of 1 mm or less or 0.5 mm or less, A wet scrubber for inducing interface activation;
A desalting tank for receiving contaminated soil from the wet scrubber, water from the water supply tank and desorbing crude oil contaminants from the soil;
A stirring tank for receiving a mixture of the contaminated soil and water from the desalting tank and supplying and stirring methanol from the methanol feeding tank;
A float sorting tank for sorting the soil and crude oil contaminants passing through the stirring tank by specific gravity so that crude oil contaminants are separated from the soil and floated to the water surface through air injection by an air injector;
A soil dehydrator for dehydrating the soil recovered through sedimentation in the floating sorting tank;
And a crude oil contaminant dehydrator for dewatering the suspended matter recovered through floating in the floating sorting tank.

[Claim 2] The water purification system of claim 1, wherein the water supply tank is supplied with water at a temperature of 40 DEG C or higher to induce desorption of contaminants.

A first step of magnetically separating iron components contained in the contaminated soil;
A second step of sorting the pollutants having passed through the first step to obtain pollutants having a predetermined particle size or less;
A third step of mixing the pollutants having a predetermined particle size or less and the surfactant selected through the second step to a predetermined particle size or less;
A fourth step of mixing the contaminants having passed through the third step with water to desorb contaminants on the surface of the soil;
A fifth step of stirring the crude oil pollutants, soil, process water, and methanol from the fourth step;
A sixth step of float-filtering the contaminants that have been submerged in the water under the surface of the water in the stirred mixture through the fifth step to float on the surface of the water through the air;
A seventh step of dehydrating the soil recovered through the sixth step;
And an eighth step of dewatering the suspended matters collected through the sixth step.

[Claim 4] The method of claim 3, wherein the fourth step comprises mixing the hot water at a temperature of 40 DEG C or higher to form a desorption condition of the contaminants.

The method of claim 3 or 4, wherein the third step comprises mixing 700 to 750 liters of water and 2 to 3 kg of surfactant per 1,000 kg of contaminated soil.

[6] The method of claim 5, wherein the fifth step is performed in a weight ratio of contaminated soil: process water: metal alcohol = 1: 3 to 9: 0.00001 to 0.002 A method of purification of soil contaminated with crude oil using interfacial activation and air.

[6] The method according to claim 3, wherein the sixth step is to suspend crude oil pollutants by injecting an air amount of 1 to 10 times / min to the capacity of the floating sorting tank A method of purification of soil contaminated with crude oil using interfacial activation and air.