KR102329745B1 - Soil remediation apparatus - Google Patents

Abstract

The present invention relates to a soil purifying device. Soil purification apparatus according to an embodiment of the present invention, a soil mixture separation chamber to which the soil mixture is supplied therein; and a bubbler disposed within the soil mixture storage chamber to generate air bubbles. Some of the particles of the soil mixture introduced into the soil mixture separation chamber are precipitated by gravity and discharged to the outside through the lower outlet of the soil mixture separation chamber. Fine soil among the soil mixture introduced into the soil mixture separation chamber is suspended by the bubbles generated by the bubbler, overflows from the upper opening of the soil mixture separation chamber, and is discharged to the outside.

Description

SOIL REMEDIATION APPARATUS

The present invention relates to a soil purifying device.

Although today's industry has been developed almost entirely on the basis of fossil fuels, the environmental pollution problem accompanying the development of the industry has recently emerged as a serious social problem.

The environmental pollution as described above can be largely divided into air pollution, water pollution, and soil pollution. In particular, the problem of soil pollution poses a very serious threat to food production, and not only causes water pollution through groundwater pollution, but is also difficult to solve compared to air pollution or water pollution.

On the other hand, oil such as petroleum among fossil fuels can be used in various industrial fields and is widely used. It can cause serious soil contamination.

Since a considerable period of time is required for soil contaminated with oil to naturally recover, interest in techniques for artificially purifying soil contaminated with oil is increasing.

As existing methods for purifying soil contaminated by oil, technologies such as soil washing, thermal desorption, and bio remedation have been proposed.

Looking at the above techniques in detail, soil washing is a technique for separating contaminants from the surface of the soil using water or a surfactant.

This soil washing method has a problem in that the consumption of surfactant becomes uneconomically excessive when the soil contaminated with heavy oil or crude oil is treated, and when water comes into contact with heavy oil or crude oil, tar balls are generated. There is a problem in that the screen is blocked by the tar ball or the contact area of the surfactant is reduced, so that the treatment effect is rapidly reduced.

Thermal desorption is a technique for purifying soil by applying heat to soil contaminated by oil to volatilize oil contaminants, and then burning the volatilized contaminants in a burner. When the volatilized pollutants are burned in the combustion chamber, dust is generated, and the generated dust is filtered through a bag filter to minimize pollutants and then discharged to the atmosphere.

This thermal desorption method requires an amount of oxygen in proportion to the carbon number of the pollutant when incinerating the pollutants volatilized from the contaminated soil. If the causative agent of soil contamination is light oil with a relatively low carbon number, there is no problem when purifying by thermal desorption method. The amount of oxygen required is also very large, and the bag filter has to be increased in proportion to it, so there is a problem that the post-treatment facility becomes very excessive.

Bio remedation is a purification technology using microorganisms, and according to the US EPA, it is generally possible to treat up to 5,000 mg/kg of TPH, and in the case of soil contaminated with heavy oil or crude oil, TPH is much higher than 5,000 mg/kg Since it is generally exceeded, there is a problem that there is a limit to the treatment by microorganisms. Here, TPH is an abbreviation of Total Petroleum Hydrocarbon, which means total petroleum hydrocarbons, and the higher the TPH value, the more serious the soil contamination level is.

In addition, when soil contaminated with crude oil is left for several decades, all light oil components with a relatively low carbon number contained in crude oil are blown away, leaving only difficult-to-decompose heavy oil components, resulting in biological decomposition. It can be difficult, and it is difficult to apply the bioremediation process itself because it is practically difficult to supply moisture and breathability necessary for microorganisms in a dry and strong sunlight environment.

In a conventional method for purifying soil contaminated by oil, a vibrating screen method is mainly used when separating water and soil particles containing desorbed oil pollutants. Such a vibrating screen method may cause screen clogging by oil contaminants.

In addition, the material and opening area of the screen mounted on the vibrating screen are determined based on the characteristics and throughput of the object to be treated. However, due to differences in treatment target soil (eg, change in particle size and particle size distribution, change in viscosity of contaminated soil, change in oil and moisture content), poor classification or insufficient treatment capacity may occur.

The holes of the screen are clogged by water containing desorbed oil pollutants flowing into the screen, fine particles among soil particles, and oil as a pollutant. Accordingly, the opening area of the screen is further reduced and there is a risk of overflow.

An embodiment of the present invention is to provide a soil purifying apparatus capable of effectively purifying soil contaminated with oil and the like, and a soil purifying facility including the same.

According to one aspect of the present invention, a soil mixture separation chamber into which the soil mixture is supplied; and a bubbler disposed in the soil mixture separation chamber to generate air bubbles, wherein some of the particles of the soil mixture introduced into the soil mixture separation chamber are precipitated by gravity to the outside through the lower outlet of the soil mixture separation chamber and fine soil among the soil mixture introduced into the soil mixture separation chamber is floated by the bubbles generated by the bubbler, overflows from the upper opening of the soil mixture separation chamber, and is discharged to the outside, a soil purification device may be provided.

The soil mixture separation chamber may include a cylindrical body portion and a hopper portion having a shape in which the cross-sectional area decreases toward the lower side, and the bubbler may be disposed under the body portion of the soil mixture separation chamber.

The soil purification apparatus includes: an opening/closing valve provided at the lower outlet of the soil mixture separation chamber, configured to open and close the lower outlet; a density sensor for measuring the density in the soil mixture separation chamber; and a controller connected to the on-off valve and the density sensor, configured to control opening and closing of the on-off valve based on a measurement value of the density sensor.

The density sensor may be installed on the upper side and the lower side of the soil mixture separation chamber, it may be configured to measure the density of the upper side and the lower side in the soil mixture separation chamber.

When the difference between the density values received from the density sensors installed above and below the soil mixture separation chamber is greater than a reference value, the control unit may control the opening/closing valve to be opened.

The soil mixture separation chamber may have an upper overflow guide, and fine soil suspended upward in the soil mixture separation chamber by the bubbles generated by the bubbler overflows from the upper opening of the soil mixture separation chamber. It may flow and be discharged to the outside through the upper overflow guide.

The density sensor may be installed below the soil mixture separation chamber, and the control unit may control the opening/closing valve to be opened when the density value received from the density sensor is equal to or greater than a reference value.

According to embodiments of the present invention, there is an effect that it is possible to effectively purify oil contaminated soil using gravity sedimentation and flotation separation.

1 is a conceptual diagram of a soil purification apparatus according to an embodiment of the present invention.
2 is a conceptual diagram of a soil purification apparatus according to a modified example of an embodiment of the present invention.

Hereinafter, specific embodiments for implementing the spirit of the present invention will be described in detail with reference to the drawings.

In addition, in the description of the present invention, if it is determined that a detailed description of a known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, when it is stated that a component is 'connected', 'connected', 'supplied', 'transferred', or 'contacted' to another component, it may be directly connected, connected, supplied, transmitted, or contacted with the other component. However, it should be understood that other components may exist in the middle.

The terminology used herein is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise.

In addition, in this specification, the expression of the upper side, the lower side, the side, etc. is described with reference to the drawings in the drawings, and it is clarified in advance that if the direction of the object is changed, it may be expressed differently. For the same reason, some components are exaggerated, omitted, or schematically illustrated in the accompanying drawings, and the size of each component does not fully reflect the actual size.

Also, terms including an ordinal number such as 1st, 2nd, etc. may be used to describe various components, but the components are not limited by these terms. These terms are used only for the purpose of distinguishing one component from another.

The meaning of "comprising," as used herein, specifies a particular characteristic, region, integer, step, operation, element and/or component, and other specific characteristic, region, integer, step, operation, element, component, and/or group. It does not exclude the existence or addition of

Hereinafter, with reference to FIG. 1 , a soil purification apparatus 10 according to an embodiment of the present invention will be described. 1 is a conceptual diagram of a soil purification apparatus 10 according to an embodiment of the present invention.

The soil purification apparatus 10 according to an embodiment of the present invention may receive soil (contaminated soil) contaminated with heavy oil or crude oil, and soil (purified soil) purified by removing heavy oil or crude oil contained in the provided contaminated soil can create

In this embodiment, the soil purification apparatus 10 is described as an example of receiving the contaminated soil contaminated by heavy oil or crude oil, but the spirit of the present invention is not limited thereto. For example, the soil purification apparatus 10 may be provided with contaminated soil contaminated by other types of oil as well as heavy oil or crude oil.

The soil purification apparatus 10 according to an embodiment of the present invention performs a process of separating soil particles from water containing desorbed oil pollutants.

The soil purification apparatus 10 may include a soil mixture separation chamber 100 , a bubble generator 200 , an on/off valve 300 , a density sensor 400 , and a control unit 500 .

The soil mixture separation chamber 100 may include a substantially cylindrical body portion 101 and a hopper portion 102 having a shape in which the cross-sectional area decreases toward the lower side.

In the body part 101 of the soil mixture separation chamber 100, the inlet (not shown) through which the soil mixture and process water (water injected to discharge oil pollutants and fine soil) flows, and oil pollutants and fine soil An upper overflow guide 120 through which the included process water overflows and is discharged may be provided.

A lower outlet 110 through which the precipitated soil is discharged may be provided at a lower portion of the hopper unit 101 of the soil mixture separation chamber 100 .

The upper overflow guide 120 may have an inclined bottom portion, a side wall surrounding the bottom portion, and an outlet through which fine soil, water, and oil contaminants that are provided on the side wall and move downward along the inclined bottom portion are discharged.

The fine soil, water, and oil contaminants overflowing from the upper opening of the soil mixture separation chamber 100 are moved downward along the inclined bottom of the upper overflow guide 120 to form an outlet disposed below the inclined bottom. can be released through

The particles of the soil mixture introduced into the soil mixture separation chamber 100 are subjected to gravity, buoyancy, and cohesive force. Heavy particles among the particles of the soil mixture introduced into the soil mixture separation chamber 100 are precipitated by gravity.

The bubble generator 200 may generate bubbles by injecting air for floatation. The bubbler 200 may be disposed in the soil mixture separation chamber 100 , for example, at a boundary between the body 101 and the hopper 102 , or at an appropriate position where the floatation can occur smoothly. The bubble generator 200 may generate microbubbles, and the generated bubbles may be attached to the fine soil including oil contaminants introduced into the soil mixture separation chamber 100 and floated upward together.

The bubbler 200 may be disposed at the boundary between the body portion 101 and the hopper portion 102 of the soil mixture separation chamber 100 , or may be disposed under the body portion 101 . The bubbler 200 is For example, it may be an air sparger.

Light particles (oil pollutants, fine soil, process water, etc.) among the particles of the soil mixture introduced into the soil mixture separation chamber 100 are suspended upward together with the bubbles generated by the bubbler 200 to the soil mixture separation chamber It overflows from the top opening of 100 and may be discharged to the outside.

The opening/closing valve 300 is provided at the lower outlet 110 of the soil mixture separation chamber 100 , and may be configured to open and close the lower outlet 110 .

Density sensor 400 is installed on the upper and lower sides of the body portion 101 of the soil mixture separation chamber 100, to measure the density of the upper and lower sides of the body portion 101 in the soil mixture separation chamber 100 have. The density sensor 400 disposed on the lower side is disposed above the hopper unit 102 , and may be disposed below the bubble generator 200 .

The on/off valve 300 and the density sensor 400 may be connected to the control unit 500 .

The control unit 500 may be, for example, a PID controller, and may control the opening and closing of the opening/closing valve 300 based on the measured value of the density sensor 400 . For example, the control unit 500 receives the density values measured by the density sensors 400 installed on the upper and lower sides of the bubble generator 200, and the density values received from the density sensors 400 installed on the upper and lower sides. When the difference between is greater than the reference value, the opening/closing valve 300 may be opened to control the discharge of soil particles deposited in the lower portion of the soil mixture storage chamber 100 .

The control unit 500 may be implemented by an arithmetic device including a microprocessor, a memory, a communication module, and the like, and since the implementation method is obvious to those skilled in the art, further detailed description will be omitted.

The soil mixture separation chamber 100 can be used in a large capacity.

In addition, in order to increase the soil recovery rate, a vibrating screen (not shown) for dewatering may be installed at the rear end of the lower outlet 110 of the soil mixture separation chamber 100 .

Hereinafter, the operation of the soil purification apparatus 10 according to the present embodiment will be described.

First, the soil mixture of water and soil particles containing the desorbed oil pollutants is supplied into the soil mixture separation chamber 100 together with the process water through the inlet of the soil mixture separation chamber 100 together with the process water.

The bubble generator 200 generates microbubbles, and the generated bubbles are suspended together with fine soil and process water containing small and light oil contaminants in the soil mixture supplied through the inlet into the soil mixture separation chamber 100. It flows out through the upper outlet.

Large and heavy soil particles among the soil mixture supplied through the inlet into the soil mixture separation chamber 100 sink to the lower part by gravity, settle in the lower part, and are discharged through the lower outlet.

Soil particles that are introduced into the soil mixture separation chamber 100 and do not settle may come into contact with microbubbles generated by the bubbler 200 installed in the soil mixture separation chamber 100 . Among the soil particles that have been in contact with the microbubbles for a sufficient contact time, the heavy soil particles are precipitated, and water containing oil pollutants and fine soil with small and light particles can be separated by floating by the bubbles together with the process water.

The control unit 500 controls the opening and closing of the opening/closing valve 300 based on the difference between the measured values of the density sensor 400 installed on the upper side and the lower side.

When the difference between the density values received from the density sensor 400 installed on the upper side and the lower side is greater than the reference value, it means that the discharge rate of the soil deposited in the lower part of the soil mixture separation chamber 100 is slow. In this case, it may be difficult to efficiently separate the soil particles staying in the soil mixture separation chamber 100 and the space in which the air bubbles can come into contact with each other is reduced.

Therefore, when the difference between the density values received from the density sensors 400 installed on the upper side and the lower side is greater than the reference value, the control unit 500 opens the on/off valve 300 so that the sedimented soil is removed from the soil mixture separation chamber 100 . Controlled to be discharged through the outlet (110). By discharging the sedimented soil, the space where the soil particles and air bubbles remaining in the soil mixture separation chamber 100 can contact increases, so that efficient separation can be performed. In this embodiment, the density sensor 400 is Although described as being provided on the upper and lower sides of the bubbler 200 of the mixture separation chamber 100, the spirit of the present invention is not limited thereto. The density sensor 400 may be provided only at the lower side of the bubbler 200 of the soil mixture separation chamber 100 to measure only the density of soil particles deposited in the lower portion of the soil mixture separation chamber 100 . In this case, when the density value measured by the density sensor 400 is equal to or greater than the reference value, the control unit 500 may control the opening/closing valve 300 to be opened to discharge the sedimented soil.

Meanwhile, in addition to the above configuration, the soil purification apparatus 10 according to the present embodiment may further include a moisture content sensor 600 and a water supply means 700 .

The moisture content sensor 600 may measure at least one of moisture content and viscosity of the oil-contaminated soil inside the soil mixture separation chamber 100 . The moisture content sensor 600 may transmit the measured data to the controller 500 .

The water supply means 700 may supply water (process water) into the soil mixture separation chamber 100 when the moisture content inside the soil mixture separation chamber 100 is low or the viscosity is high. Due to the water of the water supply means 700, the moisture content of the oil-contaminated soil in the soil mixture separation chamber 100 is increased, and the viscosity is lowered, so that the floatation can be made more smoothly. The operation of the water supply means 700 may be controlled by the controller 500 .

When the control unit 500 recognizes that the moisture content of the oil-contaminated soil inside the soil mixture separation chamber 100 is lower than the second moisture content level or the viscosity is high to the second viscosity level through the moisture content sensor 600, water supply means Operate 700 to supply water into the soil mixture separation chamber 100 . The second moisture content level may be a value lower than the first moisture content level, and the second viscosity level may be a value higher than the first viscosity level.

According to this embodiment, it is possible to effectively separate water and soil particles containing oil pollutants desorbed by combining gravity sedimentation and flotation separation.

In addition, by separating the soil particles from the water containing the oil pollutants desorbed in the stage before the oil in the contaminated soil is emulsified by pump transfer, etc., it is possible to prevent the oil from adhering to the soil, thereby increasing the soil recovery rate.

Although the embodiments of the present invention have been described as specific embodiments, these are merely examples, and the present invention is not limited thereto, and should be construed as having the widest scope according to the basic idea disclosed herein. A person skilled in the art may implement a pattern of a shape not indicated by combining/substituting the disclosed embodiments, but this also does not depart from the scope of the present invention. In addition, those skilled in the art can easily change or modify the disclosed embodiments based on the present specification, and it is clear that such changes or modifications also fall within the scope of the present invention.

10: soil purification device 100: soil mixture separation chamber
110: lower outlet 120: upper overflow guide
200: bubble generator 300: on-off valve
400: density sensor 500: control unit
600: moisture content sensor 700: water supply means

Claims (7)

a soil mixture separation chamber into which a soil mixture containing oil pollutants and fine soil is supplied; and
a bubble generator disposed in the soil mixture separation chamber to generate air bubbles;
water supply means for supplying process water to the soil mixture separation chamber;
a moisture content sensor provided in the soil mixture separation chamber to measure at least one of a moisture content and a viscosity of the oil pollutant provided in the soil mixture separation chamber; and
In order to supply the process water to the soil mixture separation chamber, a control unit for controlling the water supply means based on at least one of a moisture content and a viscosity of the oil pollutant measured by the moisture content sensor,
Some of the particles of the soil mixture introduced into the soil mixture separation chamber are precipitated by gravity and discharged to the outside through the lower outlet of the soil mixture separation chamber,
Among the soil mixture introduced into the soil mixture separation chamber, the oil pollutants and the fine soil are suspended by the bubbles generated by the bubbler, overflow from the upper opening of the soil mixture separation chamber, and discharged to the outside;
In the control unit,
A first moisture content level and a second moisture content level smaller than the first moisture content level are preset to compare with the measured moisture content of the oil pollutant,
A first viscosity level and a second viscosity level higher than the first viscosity level are preset for comparison with the measured viscosity of the oil pollutant;
The control unit is
When the moisture content of the oil pollutant is less than or equal to the second moisture content level value, controlling the water supply means so that the process water is supplied to the soil mixture separation chamber,
When the viscosity of the oil pollutant is equal to or greater than the second viscosity level value, controlling the water supply means so that the process water is supplied to the soil mixture separation chamber,
soil purifier. The method of claim 1,
The soil mixture separation chamber includes a cylindrical body portion and a hopper portion having a shape in which the cross-sectional area decreases toward the lower side,
The bubbler is disposed under the body portion of the soil mixture separation chamber,
soil purifier. The method of claim 1,
an on-off valve provided at the lower outlet of the soil mixture separation chamber, configured to open and close the lower outlet; and
Further comprising a density sensor for measuring the density in the soil mixture separation chamber,
The control unit is
It is connected to the on-off valve and the density sensor to control the opening and closing of the on-off valve based on the measured value of the density sensor,
soil purifier. 4. The method of claim 3,
The density sensor is installed on the upper side and the lower side of the soil mixture separation chamber, and is configured to measure the density of the upper side and the lower side in the soil mixture separation chamber,
soil purifier. 5. The method of claim 4,
The control unit controls to open the on-off valve when the difference between the density values received from the density sensors installed above and below the soil mixture separation chamber is greater than a reference value,
soil purifier. The method of claim 1,
The soil mixture separation chamber has an upper overflow guide,
The oil contaminants and the fine soil suspended upward in the soil mixture separation chamber by the bubbles generated by the bubbler overflow from the upper opening of the soil mixture separation chamber and are externally through the upper overflow guide. emitted by
soil purifier. 4. The method of claim 3,
The density sensor is installed on the lower side of the soil mixture separation chamber,
The control unit controls to open the on-off valve when the density value received from the density sensor is greater than or equal to a reference value,
soil purifier.

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