JP2004141783A - Treatment system for contaminated soil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely classify contaminated substance along with fine grains in classification and cleaning of contaminated soil and prevent the contaminated substance from mixing into coarse particles. <P>SOLUTION: The treatment system 201 for the contaminated soil is constituted of a device 101 for separating and removing the contaminated substance which comprises a device 104 for forming muddy water and a device 1 for classifying the muddy water, a solid-liquid separation facility 202 for solid-liquid separating the muddy water whose coarse particles are classified and removed by the device 1 for classifying the muddy water, and a water treatment device 203 for separating and removing the contaminated substance contained in the water separated by the solid-liquid separation facility 202. The device 1 for classifying the muddy water is provided with a raw water container, a vibrating and sieving mechanism, and first and second cyclones. In the vibrating and sieving mechanism, 3 screens, a plate for receiving the muddy water and another screen are arranged in stages from below in sequence. Each screen is equipped with a water injecting mechanism to inject water downwardly toward soil and sand. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a contaminated soil treatment system used mainly for removing heavy metals contained in excavated soil.
[0002]
[Prior art]
When constructing a new building on the site of a factory, various contaminants such as cadmium, lead, copper, zinc, nickel, chromium, arsenic, and other pollutants such as volatile organochlorine compounds and oils are mixed into the excavated soil and carried out. May be done. If such contaminated soil is left as it is, the contaminants mixed in the soil may be mixed into groundwater or the like and diffused into the environment. Therefore, it is necessary to remove such contaminants by some method.
[0003]
As such a method, a technique is known in which excavated soil containing contaminants is once muddy, and then the muddy water is classified and washed (see Non-Patent Document 1).
[0004]
[Non-Patent Document 1] “Guidelines for Investigation and Countermeasures Regarding Soil and Groundwater Pollution and Operational Standards”, Water Quality Conservation Bureau, Environment Agency, Soil Environment Center, published on March 25, 1999 [0005]
[Problems to be solved by the invention]
The above classification and cleaning method classifies particles with a classification point of 75 μm, and for coarse particles (gravel, coarse sand, fine sand) of 75 μm or more, the treated soil from which contaminants have been removed, and fine particles of 75 μm or less. Minutes (silt, clay) are appropriately disposed of, for example, in the form of disposal, because they contain contaminants.
[0006]
In such a classification cleaning method, most contaminants are classified based on the idea that they will be classified together with fine particles having a particle size of 75 μm or less, but the applicant has performed the classification cleaning method in various situations. However, depending on the condition of the contaminated soil, many contaminants are mixed in the coarse particles of 75 μm or more, and the environmental standards cannot be cleared, and even the treated soil must be properly disposed of in the form of disposal. found.
[0007]
The present invention has been made in view of the above-described circumstances, and while reliably classifying contaminants together with fine particles in classifying washing of contaminated soil, preventing contamination of the contaminants into coarse particles and preventing coarse particles. It is an object of the present invention to provide a treatment system for contaminated soil that can prevent elution of contaminants slightly mixed in the particles.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a contaminated soil treatment system according to the present invention comprises a kneading mixer that mixes excavated earth and sand containing contaminants with water to produce excavated muddy water, as described in claim 1, and the kneading mixer. A muddy water preparing device comprising a storage tank for storing the produced drilling muddy water, and a mud moisture classifying device for classifying earth and sand contained in the drilling muddy water in the storage tank, and the muddy water classifying device is composed of a raw water tank and a raw water tank. A contaminant comprising a vibrating sieve mechanism provided above the raw water tank and provided with a sieve for sorting soil particles with a predetermined particle size, and a water jetting mechanism for jetting water downward toward earth and sand on the sieve. Separation and removal device,
Solid-liquid separation equipment for solid-liquid separation of the muddy water whose coarse particles have been classified and removed by the mud water classifying apparatus;
A water treatment device for separating and removing contaminants contained in the water separated by the solid-liquid separation facility.
[0009]
Further, a contaminated soil treatment system according to the present invention, as described in claim 2, a kneading mixer for preparing drilling mud by mixing excavated earth and sand containing pollutants with water, and a drilling mud prepared by the kneading mixer. And a mud water classifier for classifying sediment contained in the drilling mud in the storage tank. The mud water classifier has a first section and a second section. A vibrating sieve mechanism provided with a raw water tank divided into sections, and at least two sieves disposed above the raw water tank and sorting soil particles in at least two stages according to the particle size; and And first and second cyclones respectively connected to the first and second sections of the raw water tank so that the muddy water can be press-fitted into the sections, and water is directed downward toward the sediment on the sieve. With water injection mechanism A separating device for contaminants,
Solid-liquid separation equipment for solid-liquid separation of the muddy water whose coarse particles have been classified and removed by the mud water classifying apparatus;
A water treatment device for separating and removing contaminants contained in the water separated by the solid-liquid separation facility.
[0010]
Further, the contaminated soil treatment system according to the present invention includes the storage tank provided with a stirring mechanism for stirring the drilling mud.
[0011]
In the contaminated soil treatment system according to the present invention, a dispersant tank is connected to the storage tank.
[0012]
Further, the treatment system for contaminated soil according to the present invention, a pH sensor for measuring the pH of the drilling mud stored in the storage tank, a pH adjusting agent tank containing a pH adjusting agent, The muddy water producing apparatus is provided with a supply control means for supplying a pH adjusting agent in the pH adjusting agent tank to the storage tank so as to have a pH value.
[0013]
Further, the system for treating contaminated soil according to the present invention includes an air injection mechanism for injecting air downward toward earth and sand on the sieve at a discharge side of the sieve from a water injection position by the water injection mechanism. It is.
[0014]
In addition, the system for treating contaminated soil according to the present invention disposes a sediment agitating mechanism immediately above the sieve and on a side of the sieve where water is injected from a water injection position of the water injection mechanism to break up the soil mass on the sieve. It is constructed so that it can be glued.
[0015]
Further, the treatment system for contaminated soil according to the present invention, on the upper surface of the sieve, a damming plate that dams the earth and sand transferred on the sieve on the input side of the sieve from the water injection position by the water injection mechanism. It was erected.
[0016]
In addition, the system for treating contaminated soil according to the present invention disposes a sediment agitating mechanism immediately above the sieve and on a side of the sieve where water is injected from a water injection position of the water injection mechanism to break up the soil mass on the sieve. And an air injection mechanism for injecting air downward toward earth and sand on the sieve at a discharge side of the sieve from a water injection position of the water injection mechanism.
[0017]
Further, the treatment system for contaminated soil according to the present invention, on the upper surface of the sieve, a damming plate that dams the earth and sand transferred on the sieve on the input side of the sieve from the water injection position by the water injection mechanism. An air injection mechanism is provided which stands up and injects air downwardly toward earth and sand on the sieve on the discharge side of the sieve from the water injection position of the water injection mechanism.
[0018]
Further, the treatment system for contaminated soil according to the present invention, on the upper surface of the sieve, a damming plate that dams the earth and sand transferred on the sieve on the input side of the sieve from the water injection position by the water injection mechanism. In addition to being erected, a sediment stirring mechanism is installed just above the sieve and between the dam plate and the water injection position so that the earth mass on the sieve can be peptized.
[0019]
The present applicant considers that as a cause of a large amount of contaminants being mixed into coarse particles (gravel, coarse sand, fine sand) of 75 μm or more, first, the clay mass containing the contaminants Secondly, the water content of the sand on the sieve is reduced due to vibration by the vibrating sieve mechanism, and the contaminants are discharged in a state where the contaminants are trapped in the sediment. Thirdly, the inventor has found that the water containing pollutants is discharged together with the sediment and sediment without sufficiently draining the water on the sieve. is there.
[0020]
That is, in the system for treating contaminated soil according to the present invention, a contaminant separating / removing device including a muddy water preparing device and a muddy water classifying device, and a solid-liquid separating device for separating mud from which coarse particles are classified and removed by the muddy water classifying device. It comprises a liquid separation facility and a water treatment apparatus for separating and removing contaminants contained in water separated by the solid-liquid separation facility.
[0021]
In order to separate and remove contaminants from excavated soil containing contaminants using such a contaminated soil treatment system, first, sediment in the excavated muddy water created by the muddy water producing device is classified by a mud moisture classifying device.
[0022]
That is, in the muddy water producing apparatus, excavated earth and sand containing pollutants and water are charged into a kneading mixer, and then these are kneaded to produce excavated muddy water.
[0023]
Next, the kneaded drilling mud is transferred to a storage tank and stored.
[0024]
Next, the drilling mud stored in the storage tank of the muddy water producing device is introduced into a vibrating sieve mechanism provided in the mud moisture classifying device, and water is jetted from a water jetting mechanism toward the sediment sorted on the sieve of the vibrating sieve mechanism. Is injected downward.
[0025]
In this way, when there is earth mass in the excavated muddy water, particularly in the form of clay mass, the earth mass is first crushed by the force of the injected water, and then the earth mass in the earth mass is The pollutants contained in the water are blown off by the force of the injected water, pass through a sieve, and fall into a raw water tank. In addition, the contaminants and surface water containing the contaminants attached to the surface of the soil particles in the crushed soil mass are also blown off by the force of the jetted water, pass through the sieve, and pass through the raw water tank. To fall.
[0026]
On the other hand, even when there is no earth mass in the drilling mud, the contaminants and surface water containing the contaminants that have adhered to the surface of the soil particles in the sediment are blown off by the force of the jetted water and pass through the sieve. And fall into the raw water tank.
[0027]
Therefore, by collecting the sediment remaining on the sieve, only the sediment containing substantially no contaminants can be separated from the contaminated soil as the primary treated soil.
[0028]
Since the primary treated soil contains almost no pollutants, it can be recycled as a material for backfill soil, landfill soil, embankment and the like.
[0029]
On the other hand, muddy water in a raw water tank containing a large amount of contaminants is separated into solids and water by a solid-liquid separation equipment consisting of a cyclone, thickener, screw decanter, filter press, etc. Dispose as appropriate as secondary soil in the form of disposal.
[0030]
Next, the water separated by the solid-liquid separation equipment is subjected to a treatment for removing contaminants by a water treatment device, pH adjustment and other necessary treatments, and then appropriately discharged to a river or the like.
[0031]
Here, in the treatment system for contaminated soil according to claim 2, first, drilling mud is put on a sieve capable of mainly sorting gravels out of coarse particles, and then the same as described above on the sieve After the washing by the water jetting mechanism, the selected gravel is discharged to make the primary treated soil, and the muddy water that has passed through the sieve is dropped into the first section of the raw water tank. In addition, even if there is an earthen mass in the muddy water, the earthen mass is crushed by the force of the injection water as described above, and thus there is no possibility that the earthen mass is sorted by the sieve and discharged together with the gravel.
[0032]
Next, the muddy water stored in the first section is pressed into the first cyclone to classify, for example, 75 μm as a classification point, and the cyclone under muddy is mainly sorted into coarse sand and fine sand among coarse particles. After being put on a possible sieve, and then washed by a water injection mechanism on the sieve in the same manner as described above, the selected coarse sand or fine sand is discharged to form a primary treated soil. By repeating the procedure of dropping the muddy water that has passed through the sieve into the first section of the raw water tank, as much coarse sand and fine sand as possible can be sorted out and collected without pollutants. Incidentally, even when the earth mass is generated by the vibration action on the sieve, the earth mass is crushed by the force of the jet water as described above, so that the earth mass is sorted by the sieve and discharged together with the coarse sand and the fine sand. There is no danger.
[0033]
Here, in the first cyclone, the contaminant comes over as a cyclone over mud with fine particles (silt, clay) smaller than 75 μm, but on the other hand, it sufficiently prevents the contaminant from being mixed into the under mud. It is difficult.
[0034]
Therefore, with respect to the cyclone under mud, contaminants are removed by the above-mentioned water washing together with sorting and collecting coarse sand and fine sand.
[0035]
On the other hand, muddy water over the first cyclone contains many contaminants as described above, but on the other hand, it is difficult to sufficiently classify soil particles larger than 75 μm, especially fine sand. Mix into the over mud. The accumulated amount during the circulation cleaning / circulation sorting of the mud in the first section described above is an amount that cannot be ignored.
[0036]
Therefore, the muddy water that has exceeded the first cyclone is stored in the second section of the raw water tank, and then the muddy water stored in this section is injected into the second cyclone, for example, with a classification point of 75 μm as a classification point. I do.
[0037]
Here, as for the cyclone under mud of the second cyclone, fine sand is classified and contaminants are mixed. Therefore, this is put on a sieve capable of sorting coarse sand and fine sand described above. Then, after washing by the water injection mechanism on the sieve in the same manner as described above, the selected fine sand is discharged to be the primary treated soil, and the muddy water that has passed through the sieve is supplied to the raw water tank. Drop into the first compartment. After that, as described above, the fine sand mixed into the mud in the second compartment is removed in a form containing no contaminants by performing the circulating washing and sorting on the mud in the first compartment as described above. Selectively collect.
[0038]
Since the primary treated soil contains almost no pollutants, it can be recycled as a material for backfill soil, landfill soil, embankment and the like.
[0039]
On the other hand, in the cyclone over mud of the second cyclone, most of the coarse particles (gravel, coarse sand, fine sand) of 75 μm or more are separated and removed, and the contaminants are contained in a concentrated state. .
[0040]
Therefore, the mud that has passed over the second cyclone is separated into solids and water by a solid-liquid separation facility including a thickener, a screw decanter, a filter press, and the like. Dispose of as appropriate in the form of disposal.
[0041]
Next, the water separated by the solid-liquid separation equipment is subjected to a treatment for removing contaminants by a water treatment device, pH adjustment and other necessary treatments, and then appropriately discharged to a river or the like.
[0042]
The solid-liquid separation equipment appropriately employs cyclones, thickeners, screw decanters, filter presses, etc., so that solids and water can be separated from muddy water composed mainly of clay and silt and contaminants. In this case, the configuration may be appropriately made by a known technique.
[0043]
The water treatment apparatus may be configured to be capable of separating and removing contaminants contained in water separated by the solid-liquid separation equipment. If the target contaminant is a heavy metal, for example, the heavy metal is separated and removed by chelation treatment. What should I do?
[0044]
The kneading mixer may be of any structure and type as long as it can knead the excavated earth and sand and water.
[0045]
The specific configuration of the storage tank is arbitrary as long as it can temporarily store the drilling mud produced by the kneading mixer, but if the storage tank is provided with a stirring mechanism for stirring the drilling mud, The drilling mud produced in the above is stirred by a stirring mechanism.
[0046]
In this way, it is possible to reduce the amount of the lumps existing in the excavated muddy water, and it is possible to reduce the burden of crushing the lumps in the mud moisture classifier.
[0047]
The stirring mechanism can be constituted by a sand pump, for example.
[0048]
When a dispersant tank is connected to the storage tank, the dispersant is appropriately supplied from the dispersant tank into the storage tank.
[0049]
In this way, the soil particles in the excavated mud are dispersed in the storage tank, and are prevented from agglomerating into a lump, and the pulverized soil particles are prevented from reaggregating into a lump by the stirring mechanism. be able to.
[0050]
As the dispersant, for example, a known dispersant used for underground continuous walls, for example, sodium carbonate can be used, and sodium hexametaphosphate and the like can also be used.
[0051]
Here, the solubility of the contaminant in the storage tank depends on the pH, and a pH sensor for measuring the pH of the drilling mud stored in the storage tank, and a pH adjuster tank containing a pH adjuster, Supply control means for supplying the pH adjusting agent in the pH adjusting agent tank to the storage tank so that the drilling mud has a desired pH value, the pH capable of suppressing the elution of contaminants. The value (pH range) is grasped in advance, this is set to the target pH value, and the pH value of the drilling mud stored in the storage tank is measured by the pH sensor so that the measured value becomes the target pH value. The supply control means controls the supply of the pH adjusting agent in the pH adjusting agent tank to the storage tank.
[0052]
In this way, the contaminants in the drilling mud are in a state where their elution is suppressed and the concentration of the contaminants is reduced. The substance can be more reliably removed.
[0053]
The vibrating sieve mechanism may have any configuration as long as a sieve is provided so as to select soil particles having a predetermined particle size by vibrating action. It is general that the excavated sediment is passed through the sieves in order from the one with the largest opening, and the sediment with the larger particle size is generally selected in order. However, the number of sieves is arbitrary.
[0054]
It is desirable that the water jetting mechanism be configured so that high-pressure water can be jetted as far as possible without causing any trouble in sorting the soil and the sieve.
[0055]
The jetting direction of the water jetting mechanism needs to be downward, but the term “downward” as used in the present specification is not limited to the vertical downward direction. It is conceivable that the cleaning efficiency can be improved by doing so.
[0056]
Regarding the earth and sand from which the contaminants have been blown off by the water jetted from the water jetting mechanism, the soil may be collected as it is as treated soil, but it may be collected on the sieve at the discharge side of the sieve from the water jetting position by the water jetting mechanism. In the case where an air injection mechanism that injects air downward toward the earth and sand is provided, it becomes possible to remove water from the earth and sand from which water has been injected by the water injection mechanism, thereby reducing the water content of the treated soil in advance. In addition to this, contaminants slightly adhering to the coarse particles due to the presence of water can be reliably dropped below the sieve.
[0057]
It is desirable that the air injection mechanism be configured so as to inject high-pressure air as much as possible within a range that does not hinder the selection of earth and sand and does not damage the sieve.
[0058]
The injection direction of the air injection mechanism needs to be downward, but the downward direction in this specification is not limited to the vertical downward direction as in the case of the water injection mechanism. It is conceivable to increase the moisture removal efficiency by injecting diagonally downward.
[0059]
As described above, the soil content of the sieve on the sieve decreases due to the vibration action, and tends to be in the form of earth mass. Therefore, if it is configured immediately above the sieve and a sediment agitating mechanism is installed on the input side of the sieve from the water injection position of the water injection mechanism so that the earth mass on the sieve can be peptized, By driving the stirring mechanism, the soil mass on the sieve is peptized in advance, and the subsequent step of washing with water can be performed more reliably.
[0060]
On the other hand, the transfer speed of the sediment on the sieve is set to be large to some extent from the viewpoint of the overall efficiency of sediment separation, and although the water content decreases due to the vibrating action, without sufficient draining, the coarse particles are not removed. Often they are emitted.
[0061]
In such a case, a blocking plate for blocking the earth and sand transferred on the sieve on the input side of the sieve from the water injection position by the water injection mechanism is provided upright on the upper surface of the sieve. Once the transferred earth and sand is once blocked by the blocking plate, sufficient drainage can be performed. By the way, since the transferred sediment is constantly being sent in from the input side, the sediment that has been dammed, combined with the vibrating action, passes over the damming plate in order from the one that has been sufficiently drained, and then is washed with water. Will be done.
[0062]
In addition, the above-mentioned earth and sand stirring mechanism, the air injection mechanism, and the dam plate can be used in an appropriate combination.
[0063]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of a contaminated soil treatment system according to the present invention will be described below with reference to the accompanying drawings. In addition, the same reference numerals are given to components and the like that are substantially the same as those in the related art, and description thereof is omitted.
[0064]
FIG. 1 is a block diagram showing a system for treating contaminated soil according to the present embodiment. As can be seen from the figure, a contaminated soil treatment system 201 according to the present embodiment includes a pollutant separation / removal device 101 including a muddy water producing device 104 and a mud moisture classifying device 1, and coarse particles are classified by the muddy moisture classifying device 1. The system comprises a solid-liquid separation facility 202 for solid-liquid separation of the removed muddy water, and a water treatment apparatus 203 for separating and removing contaminants contained in the water separated by the solid-liquid separation facility.
[0065]
As shown in FIG. 2, the contaminant separation / removal device 101 is a kneading mixer 102 for mixing excavated earth and sand containing contaminants with water to produce drilling mud and a storage tank for storing the drilling mud produced by the kneading mixer. The muddy water producing apparatus 104 includes a muddy water classifying apparatus 103 and the muddy water classifying apparatus 1 that classifies earth and sand contained in the excavated muddy water in the storage tank 103.
[0066]
The kneading mixer 102 can be constituted by, for example, a twin-screw stirring mixer.
[0067]
The storage tank 103 is configured to store the drilling mud kneaded and manufactured by the kneading mixer 102, and a sand pump 105 as a stirring mechanism is installed in the storage tank so that the drilling mud can be stirred and mixed. In addition, a dispersant tank 107 containing a dispersant for dispersing the soil particles in the storage tank 103 is stored so that the soil particles in the drilling mud do not agglomerate by flocculation or grow further into a clump of earth. It is connected to the tank 103 in communication.
[0068]
As the dispersant, for example, a known dispersant used for underground continuous walls, for example, sodium carbonate can be used, and sodium hexametaphosphate and the like can also be used.
[0069]
In addition, a slurry pump 106 for pumping the drilling mud in the storage tank to the mud moisture classifying apparatus 1 is provided in the storage tank 103.
[0070]
On the other hand, as shown in FIG. 3, the mud moisture classifying apparatus 1 includes a raw water tank 2, a vibrating sieve mechanism 3 provided above the raw water tank and provided with a sieve for sorting soil particles having a predetermined particle size. A cyclone 4a as a first cyclone and a cyclone 4b as a second cyclone are provided above the vibrating sieve mechanism and connected so that the muddy water in the raw water tank 2 can be press-fitted.
[0071]
The raw water tank 2 is internally divided into a section 5a as a first section and a section 5b as a second section, and the section 5a is connected to a slurry pump 6a in communication with the section 5a. By connecting to the cyclone 4a, the muddy water in the section 5a can be pressed into the cyclone 4a.
[0072]
Similarly, a slurry pump 6b is connected in communication with the section 5b, and by connecting the pump to the cyclone 4b, muddy water in the section 5b can be pressed into the cyclone 4b.
[0073]
The vibrating sieve mechanism 3 is configured such that a screen as a sieve is installed in a five-bed system inside a box-shaped frame body 7 on which a vibrator (not shown) is installed. That is, in the frame 7, a screen 8, a screen 9, a screen 10, a mud receiving plate 11 and a screen 12 are installed in a stepwise order from the bottom. There is provided a charging chute 13 for charging. The screens 8 and 9 sort the gravels, which are mainly coarse particles, while transferring the earth and sand in the excavated mud fed through the input chute 13 to the discharge side on the right side in FIG. These openings are set so that they can be discharged as primary treated soil 14 from.
[0074]
Similarly, the screens 10 and 12 sort coarse sand and fine sand, which are coarse particles, while transferring the earth and sand in the cyclone under mud from the cyclones 4a and 4b to the discharge side, and perform primary treatment from the ends thereof. The openings are set so that the soil 14 can be discharged. The muddy water receiving plate 11 is made of, for example, an iron plate, and the under muddy water of the cyclone 4a that has passed through the screen 12 is dropped directly on the raw water tank 2 without falling onto the screen 10 below the cyclone 4a. It is designed not to increase the ratio.
[0075]
The primary treated soil 14 discharged from the vibrating sieve mechanism 3 is conveyed by a belt conveyor 15, subjected to dehydration treatment or solidification treatment as necessary, and then buried in the original excavation area.
[0076]
FIG. 4 is a detailed view of the screens 8 and 9. As can be seen from the figure, the mud moisture classifying apparatus 1 is provided with a water jetting mechanism 22 for jetting water downward toward the earth and sand 21 and 21a on the screens 8 and 9. , 9 and a high-pressure water pump 25 for supplying high-pressure water to the injection nozzles.
[0077]
Further, the mud moisture classifying apparatus 1 is provided with an air injection mechanism 26 for injecting air downward toward earth and sand on the screen on the discharge side of the screens 8 and 9 from the water injection position of the water injection mechanism 22; The air injection mechanism includes injection nozzles 27 for injecting air to the screens 8 and 9 and an air compressor 28 for high-pressure air injection for forcing high-pressure air to the injection nozzles.
[0078]
In addition, immediately above the screens 8 and 9 and closer to the input side of the screen than the water injection position of the water injection mechanism 22, the earth and sand agitating mechanism 29, 29, the earth and sand stirring mechanism is provided with a stirring blade 31 protruding radially from a rotating rod, and the rotating rod is moved in a direction opposite to the direction in which the earth and sand 21 and 21a are transported. The screens 8 and 9 can be crushed and deflocculated by rotating them around the horizontal axis.
[0079]
Further, on the input side of the screens 8 and 9 relative to the water injection position of the water injection mechanism 22, damming plates 32 and 32 for damping the earth and sand 21 transferred on the screens stand on the upper surfaces of the screens 8 and 9, respectively. It is set up.
[0080]
FIG. 5 is a detailed view of the screens 12 and 10. As can be seen from the figure, the water jetting mechanism 22 can jet water downward also to the earth and sand 41, 43 on the screens 12, 10 via the jetting nozzles 23, 23.
[0081]
Further, the air injection mechanism 26 can inject air downward through the injection nozzles 27 and 27 to the earth and sand 41 and 43 on the screen on the discharge side of the screens 12 and 10 from the water injection position of the water injection mechanism 22. It has become.
[0082]
FIG. 6 is a schematic diagram showing the water treatment facility 202. As can be seen from the figure, the water treatment facility 202 temporarily stores muddy water containing fine particles and contaminants pumped from the mud moisture classifying apparatus 1, and sediments and concentrates the temporarily stored muddy water. A thickener 205; a thickening tank 208 for extracting and storing the concentrated muddy water collected at the bottom of the thickener; a coagulant tank 206 and a PAC tank 207 connected to the thickening tank; and a concentrated muddy water in the thickening tank 208. And a filter press 209 for pressurizing and dewatering the cake. The cake dewatered by the filter press is disposed of as a secondary treatment soil 210 by disposal or the like, while the filtered water from the filter press is passed through a filtration tank 211. After being temporarily stored, the water is pressure-fed to the water treatment device 203.
[0083]
If the contaminant is, for example, a heavy metal, the water treatment apparatus 203 may be configured to separate and remove the heavy metal by chelating. Many of such water treatment apparatuses 203 are already commercially available, and may be appropriately selected from them.
[0084]
In order to separate and remove heavy metals such as cadmium, lead, copper, zinc, nickel, chromium, and arsenic from excavated soil using the contaminated soil treatment system 201 according to the present embodiment, first, a backhoe or the like is used from an excavated area. After excavating earth and sand, the excavated earth and sand is thrown into a vibrating screen as needed to remove contaminants of 70 mm or more.
[0085]
Next, the excavated earth and sand is conveyed by a belt conveyor, which is a fixed-quantity feeder, and the excavated earth and sand is supplied to the muddy water producing device 104 so as to be constant in amount per unit time so as to be muddy and formed as excavated muddy water.
[0086]
In preparing the drilling mud, the excavated earth and sand and water are put into the kneading mixer 102 to knead them, and then the kneaded drilling mud is transferred to the storage tank 103. By operating the sand pump 105 to stir and mix the excavated mud in the storage tank, and by appropriately adding a dispersant to the excavated mud from the dispersant tank 107, it becomes a cause of forming an earth mass in the excavated mud. Aggregation and flocculation of soil particles are prevented as much as possible.
[0087]
Next, the slurry pump 106 is operated to pump the drilling mud in the storage tank 103 to the mud moisture classifying apparatus 1. Then, the excavated muddy water is dropped onto the screens 8 and 9 via the input chute 13, and large gravels and concrete gala having coarse particles are removed on the screen 9 having the largest aperture of, for example, 40 mm. Select and remove.
[0088]
Here, in the sorting and removing, first, the earth and sand 21 transferred on the screen 9 is once blocked by the blocking plate 32.
[0089]
By doing so, the soil 21 is subjected to the vibrating action of the vibrating sieve mechanism 3 in a state where it is blocked, so that sufficient drainage can be performed. By the way, since the earth and sand 21 are continuously fed from the input side, the earth and sand 21 which has been dammed passes over the damming plate 32 in order from the one after the sufficient drainage is completed, in combination with the vibration action.
[0090]
Next, the clay lumps still contained in the drilling mud fed from the storage tank 103 and the clay lumps newly generated by the dehydration by vibrating action on the screen 9 are mixed with the stirring blades 31 of the earth and sand stirring mechanism 29. Peptized apart.
[0091]
Next, high-pressure water is injected from the injection nozzle 23 of the water injection mechanism 22 toward the earth and sand 21 on the screen 9, and the injection direction is obliquely downward so as to oppose the transfer direction of the earth and sand 21 in order to increase the cleaning efficiency. Set to.
[0092]
In this way, when the soil mass, especially the clay mass, which has not been peptized by the earth and sand stirring mechanism 29 is present in the earth and sand 21, the mass of the earth mass is first crushed by the force of the injection water, and then the mass of the earth mass is The heavy metal contained therein is blown off by the force of the jet water, passes through the screens 8 and 9, and falls into the raw water tank 2. In addition, of the crushed sediment derived from the lumps, heavy metal and surface water containing the heavy metal, which have adhered to the surface of coarse particles such as gravel and concrete gala, are similarly blown off by the force of the jet water, and the screen 8, 9 and falls into the raw water tank 2.
[0093]
On the other hand, even when there is no earth mass, the heavy metal and the surface water containing the heavy metal that have adhered to the surface of the earth particles in the earth and sand 21 are blown off by the force of the jet water together with the coarse particles and the fine particles that are not sorted by the screen 9. Then, it falls through the screens 8 and 9 into the raw water tank 2.
[0094]
In such a state, for example, only the gravels 33 remain on the screen 9.
[0095]
Next, the air injection mechanism 26 is operated to inject high-pressure air from the injection nozzle 27 toward the gravel 33 on the screen 9, and in order to increase the efficiency of removing moisture, the injection direction is opposed to the transfer direction of the gravel 33. The angle is set obliquely downward, for example, about 30 ° rearward.
[0096]
It is desirable that the high-pressure air is, for example, ² to 4 kg / cm ² and is injected in a curtain shape.
[0097]
In this way, it is possible to remove water from the gravel 33 from which air has been injected by the air injection mechanism 26, and it is possible to reduce the water content of the treated soil in advance, and to slightly reduce the gravel due to the presence of water. The heavy metal adhering to 33 can be reliably dropped below the screen 9.
[0098]
As described above, a series of operations such as the injection of drilling mud, the draining by the dam plate 32, the peptization of the clay mass by the earth and sand stirring mechanism 29, the blowing of heavy metal by the water jetting mechanism 22, and the blowing of moisture by the air jetting mechanism 26 are screened. 9, the gravel 33 finally containing no heavy metal and having a small water content is sorted on the screen. The gravel 33 is carried out by the belt conveyor 15 and collected as the primary treated soil 14.
[0099]
Next, the earth and sand 21a that has passed through the sieve of the screen 9 is treated in the same manner as described above. That is, since there is a concern that the gravels 33a having a small particle size remain in the earth and sand 21a and that the clay lumps 30 are newly formed on the screen 8, the draining by the damming plate 32 and the clay lumps by the earth and sand stirring mechanism 29 are performed. A series of operations are performed on the screen 8, such as peptization of water, blowing of heavy metal by the water jetting mechanism 22, and blowing of moisture by the air jetting mechanism 26.
[0100]
In this manner, similarly to the sorting operation on the screen 9, the gravel 33a that does not contain heavy metals and has a small water content is finally sorted on the screen, and is conveyed out by the belt conveyor 15 to perform the primary treatment. Collect as soil 14.
[0101]
Next, the muddy water that has passed through the screens 9 and 8 sequentially falls into the first section 5a of the raw water tank 2 and is stored therein. Therefore, the muddy water is pressed into the cyclone 4a by the slurry pump 6a. Classify as
[0102]
In this manner, soil particles having a particle diameter of 75 μm or more, that is, cyclone under muddy water containing coarse sand and fine sand as coarse particles are dropped on the screen 12.
[0103]
Here, as shown in FIG. 5, the screen 12 is provided with openings so that sand, particularly coarse sand, can be selected, and is configured to have an upward slope toward the discharge side to facilitate dehydration. In addition, it is configured in a step shape to reduce the overall height.
[0104]
Then, when the cyclone under mud is injected from the cyclone 4a, first, a large amount of the water passes through the screen 12 and falls to the muddy water receiving plate 11, which is returned to the first section 5a of the raw water tank 2. It is.
[0105]
Next, while the sediment 41 remaining on the screen 12 is transferred from the input side to the discharge side (right direction in the figure) on the screen, coarse particles corresponding to the openings are sorted out. Fine sand having a small diameter or water subjected to vibration dehydration passes through the screen 12 and falls onto the lower screen 10.
[0106]
During the sorting, the heavy metal is blown off by the water injection mechanism 22 and the water is blown off by the air injection mechanism 26 on the screen 12, so that coarse sand containing no heavy metal and having a small water content is mainly used. The coarse particles 42 are sorted on the screen, and are conveyed out by the belt conveyor 15 and collected as the primary treated soil 14.
[0107]
Like the screen 12, the screen 10 is provided with openings so as to be able to sort out sand, particularly fine sand, as shown in FIG. 5, and is easily dehydrated by having an upward slope toward the discharge side. The screen 10 is configured in a stepwise manner to reduce the overall height, and fine sand passing through the screen 12 and cyclone under mud from the cyclone 4b are introduced. Above, while the earth and sand 43 are being transferred from the input side to the discharge side (rightward in the figure) on the screen, coarse particles corresponding to the openings are sorted out, and fine particles or water having a smaller particle size are removed. , Passes through the screen 10 and falls into the section 5a of the raw water tank 2.
[0108]
In addition, even during the sorting, the blowing of heavy metal by the water injection mechanism 22 and the blowing of moisture by the air injection mechanism 26 are performed on the screen 10 so that the fine sand containing no heavy metal and having a small water content is mainly used. The coarse particles 44 to be separated are sorted on the screen, and are conveyed by the belt conveyor 15 and collected as the primary treated soil 14.
[0109]
In this way, the muddy water in the section 5a of the raw water tank 2 is pressed into the cyclone 4a, and the cyclone under muddy water is washed with the screens 12 and 10 to sequentially sort and collect coarse and fine sand. By repeating the procedure of dropping the muddy water passing through the screen into the section 5a of the raw water tank 2, as much coarse sand and fine sand as possible are surely sorted and collected without containing heavy metals. In addition, even when the earth mass is generated by the vibrating action on each of the screens 12 and 10, the earth mass is crushed by the force of the jetting water as described above. There is no risk of being discharged with fine sand.
[0110]
On the other hand, after being injected into the cyclone 4a by the slurry pump 6a, the over mud over the cyclone contains a large amount of heavy metals together with fine particles (silt, clay) smaller than 75 μm. It is stored in the section 5b of the raw water tank 2.
[0111]
However, at the time of classification in the cyclone 4a, not all heavy metals can be recovered as over muddy water, and it is difficult to avoid mixing with under muddy water. At the time of recovery, as described above, heavy metals are removed by washing with water.
[0112]
Next, the mud stored in the section 5b is over mud of the cyclone 4a, but coarse particles of 75 μm or more, especially fine sand, cannot be sufficiently classified by the cyclone. It is also mixed in.
[0113]
Therefore, the muddy water stored in the section 5b is pressed into the cyclone 4b by the slurry pump 6b, and the classification is performed again using, for example, 75 μm as a classification point. Then, the under muddy water is put into the screen 10 as already described with reference to FIG. 5, and while the fine sand is mainly sorted on the screen, the heavy metal is removed by the water injection mechanism 22 and the air is injected by the air injection mechanism 26. The water is removed, and finally fine sand containing no heavy metal and having a small water content is collected as the first treated soil 14, and the muddy water that has passed through the screen is dropped into the first section 5a of the raw water tank. After that, as described above, the fine sand mixed with the mud in the second section 5b is free from heavy metals by performing the circulating washing and circulating sorting on the mud in the first section 5a. Sort and collect with certainty.
[0114]
Next, as for the cyclone over mud of cyclone 4b, most of the coarse particles (gravels, coarse sand, fine sand) of 75 μm or more are separated and removed, and heavy metals are contained in a concentrated state. The muddy water over the cyclone 4b is pumped to the solid-liquid separation equipment 202.
[0115]
Next, in the solid-liquid separation equipment 202, first, muddy water containing fine particles and contaminants pumped from the mud moisture classifying apparatus 1 is temporarily stored in the mud storage tank 204, and then the temporarily stored muddy water is thickened. It flows into 205 and precipitates and concentrates.
[0116]
Next, the concentrated muddy water collected at the bottom of the thickener 205 is withdrawn and stored in the concentration tank 208, and the coagulant and PAC are removed from the coagulant tank 206 and the PAC tank 207 that are connected to the concentration tank. To coagulate and precipitate fine particles and heavy metals.
[0117]
Next, the concentrated muddy water in the concentration tank 208 is poured into a filter press 209 for dehydration under pressure. The cake dehydrated by the filter press is disposed of as a secondary treated soil 210 while being discarded. Is temporarily stored in the filtration tank 211 and then sent to the water treatment device 203 under pressure.
[0118]
Next, in the water treatment device 203, first, after performing pH treatment as necessary, coagulation and sedimentation are performed, and the supernatant liquid excluding the precipitated floc is again adjusted as necessary in pH. The heavy metals are separated and removed through a filter and a chelating tower, and the treated water from which the heavy metals have been separated and removed is circulated to a muddy water producing device 104 for effective use (see FIG. 1), and pH adjustment and other necessary After the treatment, release it to rivers and the like as appropriate.
[0119]
As described above, according to the contaminated soil treatment system 201 according to the present embodiment, the excavated soil containing contaminants is muddy by the muddy water producing device 1 to be excavated muddy, and the excavated muddy water is installed in the mud moisture classifying device 1. Into the vibrating sieve mechanism 3 and then water is sprayed from the water spraying mechanism 22 toward the earth and sand on each of the screens 9, 8, 12, and 10. If there is any sediment, the mass of the injected water first breaks the mass, and then the pollutants such as heavy metals contained in the mass of the mass are blown away by the mass of the injected water. Then, it passes through the screens 9, 8, 12, and 10 and falls into the raw water tank 2. In addition, the contaminants and surface water containing the contaminants attached to the surface of the soil particles in the crushed soil mass are also blown off by the force of the jetted water, pass through the sieve, and pass through the raw water tank. To fall. On the other hand, even when there is no earth mass, the contaminants adhering to the surface of the soil particles in the soil and the surface water containing the contaminants are blown off by the force of the jetted water, and each of the screens 9, 8, 12, 10 and falls into the raw water tank 2.
[0120]
Therefore, it is possible to separate only contaminated soil that contains almost no pollutants from the contaminated soil as a primary treated soil. However, according to the present invention, such primary treated soil can be recycled as backfill soil, embankment, landfill soil, or the like.
[0121]
Further, according to the contaminated soil treatment system 201 according to the present embodiment, it is possible to remove water from the earth and sand from which water has been jetted by the water jetting mechanism 22 by the air jetting mechanism 26, thereby reducing the water content of the treated soil. It can be lowered in advance, and the contaminants slightly adhering to the coarse particles due to the presence of water can be surely dropped below the screens 9, 8, 12, and 10.
[0122]
Further, according to the contaminated soil treatment system 201 according to the present embodiment, the earth and sand mass on the screens 9 and 8 is peptized in advance by driving the earth and sand agitating mechanism 29, and the subsequent step of water washing is more reliably performed. be able to.
[0123]
Further, according to the contaminated soil treatment system 201 according to the present embodiment, the dam plate 32 for damping the earth and sand transferred on the screens 9 and 8 is provided upright on the upper surface of the screen. The transferred earth and sand is once blocked by the blocking plate 32, and sufficient drainage can be performed.
[0124]
Further, according to the contaminated soil treatment system 201 according to the present embodiment, since the sand pump 105 for stirring the drilling mud is provided in the storage tank 103 of the muddy water producing device 104, and the drilling mud is stirred by the sand pump. In addition, it is possible to reduce the amount of the lumps existing in the excavated muddy water, and it is possible to reduce the burden of crushing the lumps in the mud moisture classifying apparatus 1.
[0125]
Further, according to the contaminated soil treatment system 201 according to the present embodiment, the dispersant tank 107 is connected to the storage tank 103 of the muddy water producing apparatus 104 so that the dispersant is supplied to the storage tank 103 from the dispersant tank. Therefore, the soil particles in the excavated muddy water are dispersed in the storage tank 103, and are prevented from agglomerating in the form of earth mass, and the soil particles pulverized by the sand pump 105 are again aggregated in the earth mass. Can be prevented.
[0126]
In this embodiment, the screens 9 and 8 of the mud moisture classifying apparatus 1 are provided with a dam plate 32, a sediment stirring mechanism 29, a water injection mechanism 22, and an air injection mechanism 26, and the screens 12 and 10 are provided with the water injection mechanism 22. And the air injection mechanism 26 is provided, however, the number of stages of the screen is arbitrary, and as long as the water injection mechanism 22 is installed on any one of the screens, the screen is blocked by another screen. The combination of the plate 32, the earth and sand stirring mechanism 29, the water injection mechanism 22, and the air injection mechanism 26 is not a matter of design that can be arbitrarily set according to the state of the drilling mud.
[0127]
For example, regarding the screens 9 and 8, if sufficient draining can be performed due to the transport speed of the earth and sand and the installation angle of the screen, the damming plate 32 can be omitted, and the lumps can be dismantled. If only the water jetting mechanism 22 is sufficient for stiffening, there is no need to install the earth and sand stirring mechanism 29. Further, the air injection mechanism 26 may be omitted as long as the soil and sand injected by the water injection mechanism 22 can be sufficiently drained by the subsequent draining action on the screen.
[0128]
If the screens 12 and 10 cannot be sufficiently drained due to the transport speed of the earth and sand and the installation angle of the screens, the damming plate 32 should be erected similarly to the screens 9 and 8. Alternatively, if the water jetting mechanism 22 alone is not enough to pulverize the earth mass and preliminary pulverization is required, the earth and sand stirring mechanism 29 may be installed in the same manner as the screens 9 and 8.
[0129]
Further, in the present embodiment, the raw water tank 2 of the mud moisture classifying apparatus 1 is divided into two sections 5a and 5b, and the mud moisture classifying apparatus 1 is provided with two cyclones 4a and 4b. The raw water tank may be used as one section, and another mud moisture class device may be used in which the cyclone is omitted.
[0130]
FIG. 7 shows a mud moisture classifier 51 showing such a modification.
[0131]
The mud water classifier 51 shown in the figure includes a raw water tank 52, and a vibrating sieve mechanism 3 provided above the raw water tank and provided with a sieve for selecting soil particles having a predetermined particle size. A slurry pump 56 is connected to 52 so that muddy water in the raw water tank 52 can be supplied from above the vibrating sieve mechanism 3 by the pump. The configuration of the water jetting mechanism 22, the air jetting mechanism 26, the dam plate 32, and the sediment stirring mechanism 29 and the operation and effect thereof are the same as those in the above-described embodiment, and thus the description thereof is omitted here.
[0132]
This configuration is almost the same as the embodiment except for the cyclone, and the muddy water stored in the raw water tank 52 is pumped up by the slurry pump 56 and passed through the screens 9, 8, 12, and 10, The sediment was sorted out while draining by the damming plate 32, peptizing the clay lump by the earth and sand stirring mechanism 29, washing the contaminant with the water jetting mechanism 22, and removing water by the air jetting mechanism 26, and passed through the screen. The muddy water is returned to the raw water tank 52, and a series of operations of passing the muddy water through the screens 9, 8, 12, and 10 again is repeated, so that the earth and sand containing almost no pollutant is collected as the primary treated soil. It is possible.
[0133]
Since a large amount of contaminants will eventually be contained in the muddy water in the raw water tank 52, the contaminants may be pumped up by the slurry pump 57 and sent to the water treatment device 203 to perform the above-described water treatment. .
[0134]
Also in this configuration, various combinations can be considered for the combination of the dam plate 32, the earth and sand stirring mechanism 29, and the air injection mechanism 26, as in the above-described embodiment.
[0135]
Although not specifically mentioned in the present embodiment, the solubility of the contaminants in the storage tank 103 may depend greatly on the pH as in heavy metals. In such a case, if the solubility of the contaminants is high, the The concentration of the contaminants in the mud increases, and there is a case where the classification and removal of the contaminants is limited even if the mud moisture classifier 1 is used.
[0136]
FIG. 8 shows a muddy water producing apparatus 111 showing a modified example suitable for such a case. As shown in the figure, the muddy water producing device 111 mixes the excavated earth and sand containing the contaminant with water to produce the excavated muddy water and the excavated muddy water produced by the kneaded mixer as in the above-described embodiment. The storage tank 103 is provided with a sand pump 105 and a dispersant tank 107 is connected to the storage tank 103. In this modification, the drilling mud stored in the storage tank 103 is further provided. A pH sensor 112 for measuring pH, pH adjuster tanks 113a and 113b containing pH adjusters, and a pH adjuster stored in the pH adjuster tanks 113a and 113b so that the drilling mud has a desired pH value. A pH control agent supply control device 114 is provided as a supply control means for supplying to the tank 103.
[0137]
In the muddy water producing apparatus 111, first, a pH value (pH range) at which elution of contaminants can be suppressed is grasped in advance, and this is set as a target pH value. If the target pollutant is lead, there is also an effect of other substances contained in the excavated earth and sand, but for example, it is conceivable to set the target pH value to about 9. By the way, in the case of lead, the solubility increases on both the acidic side and the strong alkali side, and the solubility becomes minimum at about pH 9.
[0138]
Next, while measuring the pH of the drilling mud stored in the storage tank 103 with the pH sensor 112, the pH adjusting agent tank 113a is used by using the pH adjusting agent supply control device 114 so that the measured value becomes the target pH value. , 113b to the storage tank 103.
[0139]
Specifically, when the pH value is 11 because the drilling mud contains a large amount of concrete waste, the valve 115a is opened using the pH adjusting agent supply control means 114, and the pH adjusting agent tank 113a is opened. Is supplied to the storage tank 103. When the drilling mud is almost neutral, the valve 115b is opened using the pH adjusting agent supply control means 114, and the alkaline solution contained in the pH adjusting agent tank 113b is supplied to the storage tank 103.
[0140]
In this way, the contaminants in the drilling mud are in a state where their elution is suppressed and the concentration of the contaminants is reduced. , It is possible to remove contaminants with higher cleanliness.
[0141]
【The invention's effect】
As described above, according to the contaminated soil treatment system of the present invention, the contaminants attached to the surface of the soil particles in the soil and the surface water containing the contaminants are blown off by the force of the injected water. It is. Therefore, in the classification and washing of the contaminated soil, the contaminant can be surely classified together with the fine particles, and the contamination of the contaminant into the coarse particles can be prevented.
[0142]
[Brief description of the drawings]
FIG. 1 is a schematic diagram of a contaminated soil treatment system 201 according to an embodiment.
FIG. 2 is a schematic diagram of an apparatus 101 for separating and removing contaminants.
FIG. 3 is a schematic diagram of a mud moisture classifying apparatus 1.
FIG. 4 is a detailed sectional view of screens 9 and 8;
FIG. 5 is a detailed sectional view of the screens 12 and 10;
FIG. 6 is a schematic diagram of a water treatment facility 202.
FIG. 7 is a schematic diagram of a mud moisture classifier according to a modification.
FIG. 8 is a schematic view of a muddy water producing apparatus according to a modification.
[Explanation of symbols]
1,51 Mud moisture class device 2,52 Raw water tank 3 Vibrating sieve mechanism 4a First cyclone 4b Second cyclone 5a First section 5b Second section 8,9,10,12 Screen (screen)
Reference Signs List 22 water injection mechanism 26 air injection mechanism 29 earth and sand stirring mechanism 32 damming plate 101 contaminant separation and removal device 102 kneading mixer 103 storage tanks 104 and 111 muddy water production device 105 sand pump (stirring mechanism)
107 Dispersant tank 112 pH sensors 113a, 113b pH adjuster tank 114 pH adjuster supply control device (supply control means)
201 Contaminated soil treatment system 202 Solid-liquid separation equipment 203 Water treatment equipment

Claims (11)

A kneading mixer that mixes excavated earth and sand containing contaminants with water to create drilling mud and a mud making apparatus including a storage tank that stores the drilling mud made by the kneading mixer, and a drilling mud in the storage tank. Vibrating sieve mechanism comprising a mud moisture classifying device for classifying soil and sand to be separated, and the mud moisture classifying device is provided with a raw water tank and a sieve disposed above the raw water tank and for sorting soil particles with a predetermined particle size. And a separation and removal device for contaminants constituted by a water injection mechanism that injects water downward toward the earth and sand on the sieve,
Solid-liquid separation equipment for solid-liquid separation of the muddy water whose coarse particles have been classified and removed by the mud water classifying apparatus;
A water treatment device for separating and removing contaminants contained in water separated by the solid-liquid separation facility. A kneading mixer that mixes excavated earth and sand containing contaminants with water to create drilling mud and a mud making apparatus including a storage tank that stores the drilling mud made by the kneading mixer, and a drilling mud in the storage tank. And a mud moisture classifying device for classifying sediment to be separated, and the mud moisture classifying device is provided with a raw water tank having an interior divided into a first section and a second section, and disposed above the raw water tank to reduce the particle size. A vibrating sieve mechanism provided with at least two sieves for sorting soil particles in at least two stages, and muddy water in the first and second compartments of the raw water tank above the vibrating sieve mechanism can be press-fitted. A first and second cyclone respectively connected to and connected to the compartment, and a contaminant separation / removal device including a water injection mechanism for injecting water downward toward earth and sand on the sieve;
Solid-liquid separation equipment for solid-liquid separation of the muddy water whose coarse particles have been classified and removed by the mud water classifying apparatus;
A water treatment device for separating and removing contaminants contained in water separated by the solid-liquid separation facility. The contaminated soil treatment system according to claim 1 or 2, further comprising a stirring mechanism for stirring the drilling mud in the storage tank. The contaminated soil treatment system according to any one of claims 1 to 3, wherein a dispersant tank is connected to the storage tank. A pH sensor for measuring the pH of the drilling mud stored in the storage tank, a pH adjusting agent tank containing a pH adjusting agent, and a pH adjusting agent tank in the pH adjusting agent tank such that the drilling mud has a desired pH value. The treatment system for contaminated soil according to claim 1 or 2, wherein a supply control means for supplying a pH adjuster to the storage tank is provided in the muddy water producing apparatus. The treatment system for contaminated soil according to claim 1 or 2, further comprising an air injection mechanism for injecting air downward toward earth and sand on the sieve at a discharge side of the sieve from a water injection position by the water injection mechanism. . 3. A structure in which a sediment stirring mechanism is installed immediately above the sieve and on a side of the sieve where water is injected by the water injection mechanism so as to pulverize the earth mass on the sieve. A contaminated soil treatment system as described. The pollution according to claim 1 or 2, wherein a damming plate for damping earth and sand transferred on the sieve at a charging side of the sieve relative to a water injection position by the water jetting mechanism is provided upright on the upper surface of the sieve. Soil treatment system. Immediately above the sieve, a soil stirring mechanism is installed on the input side of the sieve from the water injection position of the water injection mechanism so as to be able to pulverize the earth mass on the sieve, and the water injection mechanism The treatment system for contaminated soil according to claim 1 or 2, further comprising an air injection mechanism for injecting air downward toward earth and sand on the sieve at a discharge side of the sieve from a water injection position. An erecting plate is provided on the upper surface of the sieve for damping earth and sand transferred on the sieve on the input side of the sieve more than a water injection position of the water injection mechanism, and a water injection position of the water injection mechanism is provided. The treatment system for contaminated soil according to claim 1, further comprising an air injection mechanism that injects air downward toward earth and sand on the sieve at a discharge side of the sieve. A dam plate for blocking earth and sand transferred on the sieve on the input side of the sieve from the water injection position by the water injection mechanism is erected on the upper surface of the sieve, and directly above the sieve, The treatment system for contaminated soil according to claim 1 or 2, wherein a soil agitation mechanism is provided between the dam plate and the water injection position so as to pulverize the earth mass on the sieve.

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