JP2002254063A - Clarification method and separating equipment for polluted soil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clarification method for polluted soil which reduces a clarification cost for polluted soil by improving a cleaning efficiency. SOLUTION: A soil B having a larger particle size than the prescribed one which makes it easy to separate the contaminants is firstly separated from the soil to which oil and heavy metals adhere by using a sizing machine to these separated soils A and B are added water respectively, and put into the cleaning machines 3 and 7 to remove the contaminants adhered to the surface of the soil through friction among the soils in the cleaning machines 3 and 7. Water containing the soil and contaminant is put into a separating tank full of water and the separating equipment 4 and 8 with a vibrating screen and an air supply means. in the separating tanks of these separating equipment 4 and 8, the soil is settled down by giving vibration and injecting air bubbles, and the soils and contaminants are separated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for purifying contaminated soil, which can improve the cleaning efficiency and reduce the cost for cleaning contaminated soil, and a separation apparatus used therefor.

[0002]

2. Description of the Related Art In recent years, it has become evident that various manufacturing plants and the soil at their former sites are contaminated with contaminants such as oil and heavy metals, which has become a social problem. Also,
Crude oil and fuel oil spilled by tanker and other marine accidents,
Regarding the soil on the seashore contaminated with waste oil illegally dumped from ships and the soil (including excavated soil) on which crude oil from crude oil mining sites has been attached, there is no appropriate purification method in view of cost and the like.

[0003]

From such a background,
It is desired to establish a technology for enabling the reuse of land by removing contaminants from contaminated soil, protecting the natural environment, and reusing sediment from which contaminants have been removed.

[0004] Incidentally, one of the methods for purifying contaminated soil containing oil and heavy metals is a soil washing method. The conventionally proposed soil washing method has a high concentration of contaminants and heavy oil and heavy metals. In the case of heavy oil or tar, use a large amount of water, go through multiple washing steps, or use a detergent such as a surfactant to remove contaminants attached to the surface of earth and sand Needed. Therefore, in such a soil cleaning method, in addition to the equipment cost, the cost of water treatment, the cost of a cleaning aid such as a surfactant increases, and the unit price of the treatment increases. there were.

The present invention has been made in consideration of the above-mentioned problems of the conventional method for cleaning contaminated soil, and in particular, in view of the problems of the soil cleaning method. It is a first object of the present invention to provide a method for purifying water and a separation device used for the method.

Further, the present invention can easily separate substances containing contaminants such as oil and heavy metals such as concrete husks and coal husks, further improve the washing efficiency, and reduce the purification cost of contaminated soil. A second object is to provide a method for purifying contaminated soil as described above.

[0007]

In order to achieve the above-mentioned object, a method for purifying contaminated soil according to the present invention is characterized in that the contaminant has a predetermined particle size or more which is easily separated from contaminated material such as oil and heavy metals. Is classified by a sorter, and the classified soil is added to the classified soil and introduced into a washing machine.In the washing machine, contaminants attached to the surface of the soil due to friction between the soil and the like are removed. , Water containing sediment and contaminants is introduced into a separation tank filled with water and a separation device equipped with a vibrating screen and an air supply means. And sedimentation by sedimentation to separate soil and contaminants.

[0008] The method of purifying contaminated soil is as follows.
From the soil to which contaminants such as heavy metals have adhered, the sediment having a predetermined particle size or more that easily separates the contaminants in advance is classified by a sorter, and the classified soil is watered for each classified soil.
By introducing into the washing machine, the sediment having a predetermined particle size or more classified by the sorting machine can be easily washed because the contaminants are easily separated, so that the load on the steps after the washing step is reduced. be able to. Then, the classified earth and sand, for each of the classified earth and sand, is added to the washing machine and introduced into the washing machine. In the washing machine, the contaminants attached to the surface of the earth and sand due to friction between the earth and sand are separated, and the earth and sand and the contaminants are contained. Water is introduced into a separation tank equipped with a water-filled separation tank and a vibrating screen and air supply means, and in the separation tank of the separation apparatus, sediment is vibrated and bubbles are sprayed and sedimented by blowing. Since sediment is separated from contaminants, it is possible to reliably separate and separate contaminants adhering to the surface of sediment with only a small amount of water without using a cleaning aid such as a surfactant. , The earth and sand can be reused.

[0009] In this case, the oil content of concrete shells, coal shells, etc., contained in the earth and sand having a predetermined particle size or more after the cleaning.
It is necessary to manually separate massive substances containing pollutants such as heavy metals, and to use concrete gravity and oil containing heavy metals and other pollutants such as heavy metals such as coal husks contained in the washed earth and sand using the specific gravity difference. Can be separated.

[0010] This makes it possible to easily separate substances such as concrete shells and coal shells which contain pollutants such as oil and heavy metals and which are difficult to separate the pollutants from other earth and sand,
The cleaning efficiency can be further improved, and the cost of purifying the contaminated soil can be reduced.

[0011] Further, washing water containing fine earth and sand after the washing is introduced into a specific gravity stabilizing device, and a relatively large particle diameter of the fine earth and sand is separated, and then a water treatment step is performed. be able to.

As a result, the load of the water treatment step can be significantly reduced, and the reuse rate of the washing water can be improved.

[0013] The separation apparatus of the present invention used in the method for purifying contaminated soil of the present invention includes a separation tank filled with water into which water containing soil and contaminants is introduced, and a separation tank near the bottom of the separation tank. A vibrating screen arranged to vibrate by vibrating means and passing the introduced earth and sand while applying vibration, and a vibrating screen disposed below the vibrating screen and blowing air toward the sediment on the vibrating screen. In a separation device for purifying contaminated soil, comprising a blowing air supply means and a conveying means for carrying out the settled earth and sand, a stirring device in which an outer peripheral portion is surrounded by a cylindrical body at an introduction portion of water containing soil and contaminants in a separation tank. A blade is provided, and an annular overflow trough is formed on an outer peripheral portion of the cylindrical body.

[0014] The separation device used for purifying the contaminated soil is as follows:
The vibrating screen and air supply means are used to blow air bubbles while applying vibration to the earth and sand. Therefore, contaminants separated from the earth and sand surface due to friction between the earth and sand in the washing machine are reliably separated from the earth and sand. Then, the settled earth and sand can be carried out by the conveying means.
Then, a stirring blade having an outer peripheral portion surrounded by a cylindrical body is disposed at an introduction portion of the water containing soil and contaminants in the separation tank, so that an annular overflow trough is formed on the outer peripheral portion of the cylindrical body. By synergistic action with air bubbles, pollutants are reliably separated from earth and sand, and contaminants such as oil floating in the cylinder are caused to overflow into an annular overflow trough formed on the outer periphery of the cylinder, It can be discharged efficiently.

[0015] In this case, a separating device used for purifying the contaminated soil includes a foam removing blade for rotating the foam on the surface of the water through the separation tank and discharging the same, and a vacuum device for sucking up contaminants such as oil floating on the surface of the water. Can be provided.

Thus, the contaminants separated and separated from the surface of the earth and sand can be surely separated from the earth and sand, and can be recovered together with a small amount of water. It can be performed efficiently.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the method for purifying contaminated soil of the present invention and a separation apparatus used in the method will be described below with reference to the drawings.

FIG. 1 and FIGS. 2 to 3 show an embodiment of the method for purifying contaminated soil according to the present invention.

In this method for treating soil, the soil to which contaminants such as oil and heavy metals have adhered is passed through a sorter 28, and the sediment having a predetermined particle size (Nmm) or more, at which the contaminants are easily separated, is classified by the sorter 28. I do. In this case, the classification can be determined according to the contaminated soil to be purified, but the particle size (Nmm) may be set to a particle size in the range of 20 to 50 mm (40 mm in this embodiment). desirable.

Although not particularly limited, in this embodiment, it is difficult to introduce particles having a particle diameter of 100 mm or more into the washing machines 3 and 7 described below.
It is separately classified by the sorter 28, and is easily reused by being easily washed with rinsing water.
7 can be crushed to such an extent that it can be introduced into the separator 7, and the crusher can be again subjected to the sorter 28.

The sediment A having a small particle diameter containing a large amount of contaminants, which is obtained by classifying and removing sediment having a predetermined particle diameter (Nmm) or more, is put into a hopper 1 and is conveyed by a belt conveyor 2 as shown in FIG. After being conveyed to the washing machine 3 shown in the drawing, the water is added in the washing machine 3 and the sand and sand are mutually polished by friction between the sand and sand, as shown in FIG.
Surface contaminants D are released. At this time, the magnetic substance can be removed by the magnetic separator 29 if necessary.

The washing machine 3 is not particularly limited to this type, but a rotatable drum 31 is provided.
And provided eccentrically in the drum 31,
And a rotor 32 that rotates in the opposite direction, and the drum 31 and the rotor 32 are rotated in the opposite directions while applying pressure to the earth and sand, thereby performing crushing and milling. As a result, the rubbing force between the soil and sand is applied to the soil A containing the contaminant to perform mutual polishing by friction between the soil and sand, and as shown in FIG. The sediment A can be finely sized, as shown in FIG.

Next, the water containing the sediment A and the contaminant D from which the contaminants adhered to the surface have been separated is used as a water-separated separation tank 41, a vibrating screen 42, and air supply means as shown in FIGS. Separation device 4 provided with air blow pipe 43
The sediment A and the contaminant D are separated from each other by applying vibration to the earth and sand and causing the earth and sand to settle in the separation tank 41 of the separation device 4. At this time, among the contaminants D, oil and the like float on the water surface, while heavy metals and the like float on the water.

As shown in FIGS. 5 to 8, the separation device 4
A separating tank 41 filled with water into which water containing the sediment A and the pollutant D is introduced, and a vibration tank is disposed near the bottom of the separating tank 41 so as to pass the introduced sediment A while applying vibration. A vibrating screen 42, an air blow pipe 43 disposed below the vibrating screen 42 and serving as an air supply unit for supplying air bubbles into the separation tank 41,
And a belt conveyor 44 as a transport means for carrying out the settled earth and sand A.

The sediment A in the separation tank 41 following the charging port
In the introduction part of the water containing the pollutant D, the outer peripheral part is
A stirring blade 48 surrounded by 8a is provided.
a, an upward flow or a downward flow, and further, an upward flow and a downward flow are alternately generated, and an annular overflow trough 49a connected to the overflow trough 49 is provided on the outer peripheral portion of the cylindrical body 48a. To form.

The separation tank 41 is provided with a foam removing blade 45 for causing the foam on the water surface to overflow into the overflow trough 49 and to be discharged by rotation.
A vacuum device 46 for arranging the two units 8a and 8b and sucking up the contaminants D such as oil floating on the water surface;
A partition 47 is provided downstream of the vacuum device 46 and separates the floating contaminants D from the belt conveyor 44. The contaminant D sucked up by the vacuum device 46 is sent to the oil / water separator 16 after passing through the gas / water separator 46a, where the oil and the sewage (contaminants such as oil including a small amount of water) are contaminated. ) Is separated and disposed of as industrial waste. Further, the fine sand settled below the belt conveyor 44 in the separation tank 41 is sucked up by the pump P and re-charged into the separation tank 41 together with the new earth and sand A.

The vibrating screen 42 is not particularly limited, but is made of, for example, a mesh having a size of about 5 mm. The vibrating screen 42 has a slanted separation tank 41 supported by the vibrating means 42a. It is arranged almost parallel to the bottom.

The air blow pipe 43 makes the air sent from the blower device into fine bubbles, and allows the air to pass through the vibrating screen 42. The bubbles from the air blow pipe 43 stir the earth and sand A on the vibrating screen 42 to enhance the cleaning effect, and also play a role of causing contaminants such as oil to float along with the water surface.

The belt conveyor 44 is provided along the bottom of the separation tank 41, and is provided with a dewatering vibrating means 44a above the water. On the downstream side of the vibration means 44a, a pressurized water pipe 4 for spraying pressurized water onto the water surface or water to prevent contaminants from being attracted to the conveyed earth and sand A
4b is provided. Further, if necessary, a washing water pipe 44 for washing the conveyed earth and sand A is provided upstream of the vibration means 44a and upstream of the vacuum device 46.
A cleaning water pipe 44d for preventing c and floating contaminants D from flowing out of the partition wall 47 can be provided. The pressure water pipe 44b and the cleaning water pipe 44d
May be configured to inject pressurized water, or may be configured to inject pressurized air.

Since the separation device 4 blows air bubbles while applying vibration to the earth and sand A by the vibrating screen 42 and the air blow pipe 43, the cleaning machine 3
In this case, the contaminant D separated from the surface of the earth and sand A due to friction between the earth and sand A can be reliably separated from the earth and sand, and the earth and sand A settled by the belt conveyor 44 can be carried out. In particular, a stirring blade 48 having an outer peripheral portion surrounded by a cylindrical body 48a is disposed at an introduction portion of the water containing soil and contaminants in the separation tank 41, and an annular overflow trough 48a is provided on the outer peripheral portion of the cylindrical body 48a. Because it is formed, the cylindrical body 48
a, an ascending flow or a descending flow, and further, an ascending flow and a descending flow are generated alternately.
Is reliably separated from the sediment A, and the contaminants D such as oil floating in the cylindrical body 48a are caused to flow efficiently into the annular overflow trough 49a formed on the outer peripheral portion of the cylindrical body 48a to be efficiently discharged. be able to. As a result, without using a cleaning aid such as a surfactant, the soil A
The pollutant D adhering to the surface of the soil is surely separated from the sediment A and separated, and the pollutant D such as oil can be floated by air bubbles.
It can be recovered together with a small amount of water, and can be efficiently separated and recovered by the oil-water separator 16 described later.

The sediment A settled in the separation tank 41 of the separation device 4 is taken out of the separation device 4 by the belt conveyor 44 and transported to the screen 10.

The washing water from the separation tank 41 is supplied to the water tank 1
And purified by a water treatment process described below.

On the other hand, the sediment B having a predetermined particle size (Nmm) or more, which is classified by the sorter 28, is easily separated from contaminants, and can be reused by simple washing. In the present embodiment, the earth and sand B having the predetermined particle size (Nmm) or more is put into the hopper 5 and is not particularly limited to this type by the belt conveyor 6. After being conveyed to a washing machine 7 of the same type as the washing machine 3 shown in the drawing, the contaminants D on the surface of the earth and sand A are removed by adding water in the washing machine 7 and performing mutual polishing by friction between the earth and sand. At this time, the magnetic substance can be removed by the magnetic separator 29 if necessary. Since the sediment B having the predetermined particle size (Nmm) or more is easy to separate the contaminants and can be easily washed, the sediment B having the predetermined particle size (Nmm) or more is converted into particles containing a large amount of the contaminants. By performing the washing separately from the small-diameter earth and sand A, the amount of water can be reduced, and the load of the steps after the washing step can be reduced.

The water containing the sediment B and the contaminant D from which the contaminant adhered to the surface by the cleaning machine 7 has been removed is shown in FIGS.
Is introduced into a separation device 8 of the same type as the separation device 4 shown in FIG.
And contaminant D. At this time, among the contaminants D, oil and the like float on the water surface, while heavy metals and the like float on the water.

The sediment B settled in the separation tank of the separation device 8 is taken out of the separation device 8, and on the screen 9, the sediment B having a predetermined particle size (Nmm) or more, and the particle size conveyed to the screen 10. Is separated from the sediment C that is less than that.

By the way, a predetermined particle size (Nm
m) When the above-mentioned earth and sand B contains a massive substance containing contaminants such as oil and heavy metals such as concrete shells and coal shells, the massive substance is transferred to, for example, a belt conveyor 30.
While being transported above, the worker can be manually separated. In addition, the separation of the lump-like substance may be performed by a specific gravity difference separation device such as a dust removing machine. As a result, it is possible to easily separate agglomerated substances such as concrete shells and coal husks, which contain pollutants such as oil and heavy metals, and which are difficult to separate the pollutants, from other earth and sand. The cost of purifying the contaminated soil can be reduced. The sediment separated in this way can be reused. In addition, massive substances including pollutants such as oil and heavy metals such as concrete shells and coal shells separated from earth and sand are treated as industrial waste.

The sediment A transported to the screen 10 and the sediment C separated by the screen 9 are not particularly limited. And the like. By applying earth and sand A and earth and sand C to the specific gravity difference separators 11, 12, and 13, the earth and sand A or earth and sand C contains particulate matter including contaminants such as oil and heavy metals such as concrete shells and coal shells. In this case, the granular substance can be separated by utilizing a difference in specific gravity. As a result, it is possible to easily separate granular substances such as concrete shells and coal shells, which contain pollutants such as oil and heavy metals, from which the pollutants are difficult to separate, from other earth and sand, thereby further improving the washing efficiency. The cost of purifying the contaminated soil can be reduced. The granular material containing contaminants such as oil and heavy metals such as concrete shells and coal shells separated in this manner is treated as industrial waste.

The screen 10 containing fine earth and sand and the washing water from the specific gravity difference separators 11, 12 and 13 are optionally supplied to a separator 14 of the same type as the separator 4 shown in FIGS. Introduce and separate sediment. The sediment separated in this way can be reused. The washing water containing fine earth and sand from the separation device 14 is introduced into the separation device 4.

The washing water from the separation devices 4 and 8 containing fine earth and sand is introduced into a water tank 15, and the upper water (floating component) is sent to an oil / water separator 16 where the water is separated. Oil and sewage (contaminants such as oil containing a small amount of water)
Is separated and treated as industrial waste. Further, the remaining washing water introduced into the water tank 15 is introduced into a specific gravity stabilizing device 17 such as a cyclone to separate a relatively large particle size sand out of fine soil and then to perform a water treatment step. ing. Thereby, the load of the water treatment step can be significantly reduced, and the reuse rate of the washing water can be improved.

In the water treatment step, the configuration of a conventionally known water treatment facility can be appropriately adopted according to the type of contaminants contained in the washing water introduced from the oil-water separator 16 and the specific gravity stabilizing device 17. However, in the present embodiment, the reaction vessel 1
8, PH treatment device 19, flocculation tank 20, sedimentation tank 21, PH
After being introduced into the slurry tank 23, the slurry is separated into a dewatered cake containing contaminants such as heavy metals by a dewatering device 24 such as a filter press, and the industrial waste is collected. Is processed as Further, the treated water is introduced from the drainage tank 25 into the reaction tank 18,
After being detoxified in the PH treatment device 22 of the water treatment facility, it is sent to the discharge tank 26 and discharged or stored in the water tank 27 for reuse.

As described above, according to the method for purifying contaminated soil according to the present embodiment, first, sediment having a predetermined particle size or more, from which the contaminants are easily separated, is first selected from the soil to which the contaminants such as oil and heavy metals have adhered. Classified by the classifier 28, the classified earth and sand are added to each of the classified soil A and B, and introduced into the washing machines 3 and 7, so that the particles having a predetermined particle size or more classified by the classifier 28 are obtained. Since the sediment B can be easily washed because the contaminants are easily separated, the load of steps after the washing step can be reduced. Then, the classified earth and sand was added to each of the classified earth and sand A and B and introduced into the washing machines 3 and 7, and adhered to the surfaces of the earth and sand A and B by the friction between the earth and sand in the washing machines 3 and 7. The contaminant D is removed, and the water containing the sediment A, B and the contaminant D is introduced into the separation tank 41 filled with water and the separation devices 4 and 8 including the vibrating screen 42 and the air supply means 43. In the separation tanks 41 of the separation devices 4 and 8, the sediment A and B are vibrated and air bubbles are blown to settle so that the sediment A and B are separated from the pollutant D. Without using cleaning aids such as activators,
With only a small amount of water, the contaminant D adhering to the surfaces of the earth and sand A and B can be surely separated and separated, and the earth and sand A and B can be reused.

In addition, after the washing, a massive substance containing contaminants such as oil and heavy metals such as concrete shells and coal shells contained in the earth and sand B having a predetermined particle size or more can be separated manually, or after the washing. Separation of substances containing contaminants such as oil and heavy metals such as concrete shells and coal husks contained in earth and sand A and B by using the specific gravity difference to contain contaminants such as oil and heavy metals, In addition, it is possible to easily separate materials such as concrete shells and coal shells from which contaminants are difficult to be separated from other earth and sand, thereby further improving the washing efficiency and reducing the cost of purifying the contaminated soil.

As described above, the method for purifying contaminated soil of the present invention and the separation apparatus used for the same have been described based on the embodiments. However, the present invention is not limited to the configuration described in the above embodiments, A different type of washing machine, for example, a drum having a rotatable inner peripheral surface with irregularities, and a plurality of steel rods movably loaded into the drum, by rotating the drum The configuration can be changed as appropriate without departing from the spirit of the invention, such as using a washing machine that grinds and grinds while applying pressure to earth and sand with a steel rod.

[0044]

According to the method for purifying contaminated soil of the present invention,
First, from the soil to which contaminants such as oil and heavy metals have adhered, the sediment having a predetermined particle size or more in which the contaminants are easily separated in advance is classified by a sorter, and the classified soil is watered for each classified soil. By introducing to the washing machine,
Soil and sand with a predetermined particle size or more classified by the sorter can be easily washed because pollutants are easily separated.
The load of the steps after the cleaning step can be reduced.
Then, the classified earth and sand, for each of the classified earth and sand, is added to the washing machine and introduced into the washing machine. In the washing machine, the contaminants attached to the surface of the earth and sand due to friction between the earth and sand are separated, and the earth and sand and the contaminants are contained. The water is introduced into a separation tank equipped with a water-filled separation tank and a vibrating screen and an air supply means, and in the separation tank of the separation apparatus, sediment is vibrated and bubbles are blown and bubbles are settled to cause sedimentation. Since sediment is separated from contaminants, it is possible to reliably separate and separate contaminants adhering to the surface of sediment with only a small amount of water without using a cleaning aid such as a surfactant. , The earth and sand can be reused. As a result, the cleaning efficiency is improved, and the sediment having a predetermined particle size or more is classified in the pre-process of the cleaning process, so that the load after the cleaning process is reduced, and the purification cost of the contaminated soil is reduced. can do. Further, after the cleaning step, a series of processing can be performed without classifying the earth and sand, so that the processing step can be simplified and the cost such as equipment cost can be reduced.

In addition, a massive substance containing contaminants such as oil and heavy metals such as concrete shells and coal shells contained in earth and sand having a predetermined particle size or more after washing can be separated manually, or after washing. Separation of substances containing contaminants such as oil and heavy metals such as concrete shells and coal husks contained in earth and sand by using the difference in specific gravity makes it possible to contain contaminants such as oil and heavy metals and to reduce contaminants. Substances such as concrete shells and coal shells, which are difficult to separate, can be easily separated from other earth and sand, so that the cleaning efficiency can be further improved and the cost of purifying contaminated soil can be reduced.

Further, the washing water containing the fine soil after the cleaning is introduced into a specific gravity stabilizing device, and the relatively large particle diameter of the fine soil is separated and then subjected to a water treatment step. Thereby, the load of the water treatment step can be significantly reduced, and the reuse rate of the cleaning water can be improved.

According to the separation apparatus of the present invention for purifying contaminated soil, air bubbles are blown while applying vibration to the soil by the vibrating screen and the air supply means. Pollutants separated from the surface of the earth and sand due to friction between them can be reliably separated from the earth and sand, and the settled earth and sand can be carried out by the transporting means. Then, a stirring blade having an outer peripheral portion surrounded by a cylindrical body is disposed at an introduction portion of the water containing soil and contaminants in the separation tank, so that an annular overflow trough is formed on the outer peripheral portion of the cylindrical body. By synergistic action with air bubbles, pollutants are reliably separated from earth and sand, and contaminants such as oil floating in the cylinder are caused to overflow into an annular overflow trough formed on the outer periphery of the cylinder, It can be discharged efficiently. As a result, it is possible to reliably remove and separate contaminants adhering to the surface of the earth and sand using only a small amount of water without using a cleaning aid such as a surfactant, and to reuse the earth and sand. Become.

Further, the separation device used for purifying the contaminated soil includes a foam removal blade for rotating the foam on the water surface by rotating so as to overflow the separation tank, and a vacuum device for sucking up contaminants such as oil floating on the water surface. By providing, the contaminants separated and separated from the surface of the earth and sand can be surely separated from the earth and sand, and can be collected together with a small amount of water.
Recovery can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a flowchart showing one embodiment of a method for purifying contaminated soil according to the present invention.

FIG. 2 is a flowchart (part 1) of an equipment apparatus showing one embodiment of the method for purifying contaminated soil according to the present invention.

FIG. 3 is a flowchart (part 2) of the equipment showing one embodiment of the method for purifying contaminated soil of the present invention.

FIGS. 4A and 4B show a washing machine used for purifying contaminated soil according to the present invention, wherein FIG. 4A is a cross-sectional view, FIG. 4B is a cross-sectional view showing the operation thereof, and FIG. FIG. 2D is an explanatory view showing a milling action by the washing machine.

FIG. 5 is a schematic diagram showing a separation device used for purifying contaminated soil according to the present invention.

FIG. 6 is a plan view of the same.

FIG. 7 is a front view of the same.

8A is a plan view of a main part, and FIG. 8B is a side view of the main part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hopper 2 Belt conveyor 3 Cleaning machine 31 Drum 32 Rotor 4 Separation device 41 Separation tank 42 Vibration screen 42a Vibration means 43 Air blow pipe (air supply means) 44 Belt conveyor 44a Vibration means 44b Pressure water pipe 44c Cleaning water pipe 45 Foam elimination blade 46 Vacuum device 47 Partition wall 48 Stirring blade 48a Cylindrical body 49 Overflow trough 49a Annular overflow trough 7 Washer 8 Separator 9 Screen 10 Screen 11, 12, 13 Specific gravity difference device 12 Secondary reaction tank 13 Tertiary Reaction tank 14 Separator 15 Water tank 16 Oil / water separator 17 Specific gravity stabilizer 18 Reaction tank 19 PH treatment apparatus 20 Coagulation tank 21 Sedimentation tank 22 PH treatment apparatus 23 Slurry tank 24 Dehydrator 25 Filtration tank 26 Discharge tank 27 Storage tank 28 Sorter 29 Magnetic separator 30 Bell Conveyor

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) B03B 5/00 B03B 5/18 5/18 5/28 Z 5/28 B 7/00 7/00 9/06 9 / 06 B03D 1/14 A B03D 1/02 B09B 5/00 ZABS 1/14 B03D 1/02 A (72) Inventor Takuo Nakajima 4-55, Kohohana-ku, Osaka-shi, Osaka-shi Konoike Guminai (72) Inventor Kawanishi sequentially 4-3-55, Konohana-ku, Osaka-shi, Osaka Konoike-gumi F-term (reference) 4D004 AA41 AB02 AB03 AC05 CA04 CA10 CA40 CB05 CB46 4D063 FF14 FF34 GA10 GC16 GD27 4D067 DD02 DD07 DD18 GA03 GA20 GB01 4D07 AA18 AA41 AB02 AB06 AB14 AB24 CA01 DA03

Claims (6)

[Claims] 1. A method of classifying soil and soil having a predetermined particle size or more, from which soil and contaminants such as oil and heavy metals are easily adhered, by a sorter, and adding the classified earth and sand to each of the classified earth and sand. Then, introduced into the washing machine, in the washing machine to separate contaminants attached to the surface of the earth and sand due to friction between the sand and the like, the water containing the earth and sand and the contaminants, a separation tank filled with water and a vibration screen and The sediment is introduced into a separation device provided with an air supply means, and in the separation tank of the separation device, sediment is separated from contaminants by applying vibration to the sediment and blowing bubbles to settle the sediment. How to clean contaminated soil. 2. The method according to claim 1, wherein after the washing, a massive substance containing contaminants such as oil and heavy metals such as concrete shells and coal shells contained in earth and sand having a predetermined particle size or more is manually separated. The method for purifying contaminated soil according to claim 1. 3. The method according to claim 1, wherein a substance containing contaminants such as oil and heavy metals such as concrete shells and coal shells contained in the washed earth and sand is separated by utilizing a specific gravity difference. 2. The method for purifying contaminated soil according to 2. 4. A washing water containing fine earth and sand after washing is introduced into a specific gravity stabilizing device, and a relatively large particle diameter of the fine earth and sand is separated, and then a water treatment step is performed. The method for purifying contaminated soil according to claim 1, 2, or 3. 5. A separation tank filled with water into which water containing sediment and contaminants is introduced, and provided near a bottom of the separation tank so as to vibrate by vibrating means. Contamination comprising a vibrating screen for passing while applying, an air supply means disposed below the vibrating screen to blow air bubbles toward the sediment on the vibrating screen, and a conveying means for carrying out the settled sediment. In a separation device used for purification of soil, a stirring blade having an outer peripheral portion surrounded by a cylindrical body is provided at an introduction portion of water containing soil and contaminants in a separation tank, and an annular overflow trough is provided on an outer peripheral portion of the cylindrical body. A separation device for purifying contaminated soil, characterized in that the separation device is formed. 6. The apparatus according to claim 5, further comprising: a foam removing blade for rotating the foam on the water surface to overflow from the separation tank and discharging the same; and a vacuum device for sucking up contaminants such as oil floating on the water surface. A separation device used for purifying contaminated soil according to the above.