JP6548874B2 - Method and system for cleaning contaminated soil - Google Patents

Description

  The present invention relates to a method and system for cleaning contaminated soil contaminated with harmful substances such as radioactive substances and heavy metals.

In the soil contaminated with harmful substances such as radioactive substances and heavy metals, the harmful substances are difficult to intrude into the inside of the soil particles, so they are mainly attached and adsorbed near the surface of the soil particles. Therefore, when the contamination concentration of the soil contaminated with harmful substances is compared according to the particle size of the soil particles of the component, the larger the fine particle with a large specific surface area, the higher the concentration, and the smaller the coarse particle with a small specific surface area Become. Therefore, when washing the contaminated soil, usually, water is added to the original soil to crush it (ie, the clumps of fine particles contained in the original soil are broken up and attached to the coarse particles) The fine particles are peeled off, and the soil particles are broken up, and then only the coarse particles are taken out by classification. The turbid water after taking out the coarse particles contains fine particles of the original soil, and the contamination concentration is high. Therefore, the fine particles are recovered as sludge in the turbid water treatment facility and dewatered to a high level. Dispose of as a concentration contaminant and reuse the treated water after fine particle removal for cleaning. In such a method, a water jet apparatus, a drum washer, etc. as a crushing equipment, a horizontal bucket type classifier as a classification equipment, a spiral type classifier, a cyclone type classifier, etc., and a coagulation sedimentation equipment as a turbid water treatment equipment are often used. The technique related to the cleaning method of this kind of contaminated soil is proposed by patent document 1 etc., for example.
In addition, the coarse particle fraction extracted by this method usually has a contamination concentration below the target value and becomes cleaned soil, but depending on the concentration of the original contaminated soil or the type of harmful substance, the concentration does not exceed the target value. There is nothing to do. In such a case, the contaminated soil is often excluded from being cleaned as soil that is not suitable for cleaning. However, on the other hand, attempts have been made to increase the decontamination effect somehow and to lower the concentration below the target value. In this case, since the concentration of the coarse particles only does not fall below the target value, the surface of the coarse particles adhering to and adsorbed with a large amount of harmful substances is scraped in order to lower the concentration. In order to scrape off the surface of coarse particles, for example, a device such as a special grinder called hurricane by the trade name, cavitation jet, etc. is used, and it is also carried out to use an agent for promoting surface cutting in combination. There is.

  However, with such conventional methods for cleaning contaminated soil, even if the soil cleaning plant used for this is only the basic configuration, crushing equipment, classification equipment, turbid water treatment equipment and large-scale equipment are necessary, In addition, if equipment for surface cutting related to coarse particles is provided, the plant becomes a very large scale, and both initial costs and running costs increase, resulting in poor practicability.

Therefore, the inventors of the present application, according to the prior application (Patent Document 2), are versatile and inexpensive without using surface grinding related devices and equipment such as special grinders and medicines as in the prior art. Contamination that can make surface cutting of coarse particles possible, enhance cleaning effects, and contribute to the reduction of the scale of cleaning plants and reduction of cleaning costs with extremely simple equipment using only large equipment and equipment A soil cleaning method and system was proposed.
In this cleaning method, a slurry obtained by mixing soil and water contaminated with harmful substances is placed in a container, the slurry in the container is sucked by a pump, conveyed from a pump through a transportation pipe, and returned to the container. Thus, the slurry in the container is circulated between the container, the pump, and the transport piping, circulation of the slurry is repeated by continuous operation of the pump, and coarse particles of soil are taken out by classification from the slurry after being circulated for a fixed time. The purpose of the present invention is to achieve the intended purpose by obtaining the coarse particle fraction in which the concentration of harmful substances is lower than that of the original soil.
In addition, this cleaning system includes a container for containing the slurry mixed with soil and water contaminated with harmful substances, a pump for sucking and discharging the slurry in the container, and one end connected to the pump, The end is disposed so that the slurry discharged therefrom is returned to the container, and the transport piping for conveying the slurry discharged from the pump is provided, and the slurry contained in the container is continuously pumped by the pump. And the pump and the transport piping, and the intended purpose can be realized by such a cleaning system.

JP, 2005-28290, A Japanese Patent Application No. 2013-37057

The inventors of the present invention used the cleaning method and system of the contaminated soil of the above-mentioned patent document 2, and as a result of cleaning the contaminated soil contaminated with harmful substances such as radioactive substances, expected effects were obtained. On the other hand, in this cleaning method and system, it was found that there are the following problems for circulating and cleaning the soil particles.
(1) In this cleaning method and system, since soil particles are circulated and washed, it is necessary to adopt a batch type treatment in which water is added, soil is added, mixed for a certain period of time, and taken out. It takes a certain amount of time and it is difficult to shorten the processing time. In addition, because of batch processing, there is a limit to the processing capacity of each operation, and it is difficult to expand and improve the processing capacity unless the entire apparatus is upsized.
(2) In this cleaning method and system, since soil particles are circulated and washed, a certain cleaning time (about 15 minutes) is necessary to grind the soil particles, and this constant cleaning time In order to ensure water quality, it is necessary to have facilities for circulating the slurry, such as a water tank and piping for circulation, and it is difficult to reduce the cost by further downsizing the facilities, simplifying the facilities, and downsizing the facilities and simplification. is there.

  The present invention solves the above-mentioned conventional problems, and in the cleaning method and system of the above-mentioned contaminated soil, enhancing the grinding effect of the soil particles and shortening the cleaning processing time, and further, without circulating the slurry. The purpose is to complete the cleaning process by passing the pipe once and perform the continuous process, to further reduce the size of the equipment, to simplify, and to reduce the cost.

In order to achieve the above object, the method (1) for cleaning contaminated soil of the present invention is
A method for cleaning contaminated soil in which radioactive substance-contaminated soil is cleaned by aspirating slurry mixed with radioactive substance-contaminated soil and water through a pipe and flowing it while stirring and mixing. ,
A pump capable of suction and transfer to the sand is adopted as the pump,
The pipe as a whole is formed into a substantially L shape, and is constituted by a vertical pipe which is vertically raised and a horizontal pipe which is horizontally extended, and a part or all of the pipe, The inner surface of the pipe is formed into a curved shape or an uneven shape that changes the flow of the slurry so that the slurry can be divided and dispersed in the pipe and repeatedly collides with the inner surface of the pipe, or the pipe can be flowed with the slurry Provide a static mixer consisting of bending, or a combination of these, to a length that changes the grinding time required for grinding the soil particles in the slurry .
The continuous operation of the pump passes the slurry through the pump and the pipe with the static mixer to grind particles in the slurry.
It shall be the gist.
In order to achieve the above object, the method (2) for cleaning contaminated soil of the present invention is
The slurry mixed with the soil contaminated with radioactive material and water is placed in a container, the slurry in the container is sucked by a pump, and the slurry is sent through piping to the container to return the inside of the container. A method for cleaning contaminated soil, wherein the slurry is circulated between the container, the pump, and the piping, and the soil contaminated with radioactive material is cleaned by repeating circulation of the slurry.
A pump capable of suction and transfer to the sand is adopted as the pump,
The piping as a whole is formed in a substantially inverted U-shape or a substantially inverted J-shape, and the slurry can be divided and dispersed in the piping to a part or all of the piping and the piping can be repeatedly collided with the inner surface of the piping A static mixer is provided, which is formed in a curved shape or uneven shape that changes the flow of the slurry, or by bending the pipe into a waveform that changes the flow of the slurry, or a combination thereof.
By continuous operation of the pump, the slurry contained in the vessel is repeatedly circulated among the vessel, the pump, and the piping with the static mixer to grind the soil particles in the slurry.
Make it a gist.

In order to achieve the above object, the contaminated soil cleaning system (1) of the present invention is
A pump for suctioning and delivering a slurry mixed with soil and water contaminated with radioactive material;
Piping for stirring, mixing and flowing the slurry sucked and sent out by the pump;
Equipped with
The pump is a pump capable of suction and transfer to the sand,
The piping is generally formed in a substantially L-shape, and includes a vertical piping that is vertically raised and a horizontal piping that is horizontally extended, and a part or all of the piping, The inner surface of the pipe is formed into a curved shape or an uneven shape that changes the flow of the slurry so that the slurry can be divided and dispersed in the pipe and repeatedly collides with the inner surface of the pipe, or the pipe can be flowed with the slurry A static mixer, which is bent in a wave form or a combination of these, is provided with a length that secures the grinding time required for grinding the soil particles in the slurry ,
The continuous operation of the pump passes the slurry through the pump and the pipe with the static mixer to grind particles in the slurry.
It shall be the gist.
In order to achieve the above object, the contaminated soil cleaning system (2) of the present invention is
A container for containing a slurry of soil and water contaminated with radioactive material;
A pump for suctioning and delivering the slurry in the container;
Piping for passing the slurry sucked and sent out by the pump and sending it back to the container;
Equipped with
The pump is a pump capable of suction and transfer to the sand,
The whole of the pipe is formed in a substantially inverted U-shape or a substantially inverted J-shape so that the slurry can be divided and dispersed in part or all of the pipe and can repeatedly collide with the inner surface of the pipe. There is provided a static mixer in which the inner surface of the pipe is formed into a curved shape or an uneven shape which changes the flow of slurry, or the pipe is bent into a waveform which changes the flow of slurry or a combination thereof.
By continuous operation of the pump, the slurry contained in the vessel is repeatedly circulated among the vessel, the pump, and the piping with the static mixer to grind the soil particles in the slurry.
Make it a gist.

According to the method (1) for cleaning contaminated soil of the present invention, a pump capable of suctioning and transporting to sand is adopted as the pump, and the piping as a whole is formed into a substantially L shape and can be raised vertically. The inner surface of the pipe can be divided and dispersed in the pipe in a part or all of the pipe, and the inner surface of the pipe can be repeatedly collided with the inner surface of the pipe. A static mixer consisting of curved surface shape or uneven shape that changes the flow of slurry, or bending piping to change the flow of slurry, or a combination of these is used to grind earth particles in the slurry It provided the length secured between a grinding time necessary, pump a slurry by continuous operation of the pump, since the ground soil particles in the slurry through a pipe with a static mixer, For feeding (no static mixer as described above) in comparison with the case of using a pipe, to enhance the grinding effect of the soil particles, it is possible to shorten the cleaning time. Also, in this case, the piping as a whole is formed in a substantially L-shape, and is constituted by the piping in the vertical direction and the piping in the horizontal direction. by forming a length secured between a grinding time required to further scale of the as slurry can be cleaned in one pipe passage is unnecessary equipment for circulating the slurry as a whole facility, It is possible to simplify and contribute to cost reduction.
According to the method (2) for cleaning contaminated soil of the present invention, a pump capable of sucking and transporting sand to the pump is adopted, and the pipe as a whole is formed in a substantially inverted U-shape or a substantially inverted J-shape. Alternatively, the slurry can be divided and dispersed in the pipe and repeatedly collided with the inner surface of the pipe, the inner surface of the pipe is formed into a curved shape or uneven shape that changes the flow of the slurry, or the pipe is the slurry flow Add a static mixer that bends or combines them into a corrugated shape, and by continuous operation of the pump, the slurry placed in the container is circulated repeatedly between the container, the pump, and the piping with the static mixer. since grinding the soil particles in, for transporting (without a static mixer as described above) in comparison with the case of using a pipe, to enhance the grinding effect of the soil particles They are possible to shorten the cleaning time.
In addition, this cleaning method (2) is a modification of the cleaning method of the previous application (Japanese Patent Application No. 2013-37057) by the present inventors (Japanese Patent Application No. 2013-37057). The coarse particles in the soil are removed from the slurry by classification after being circulated repeatedly between the container, pump, and piping, and circulated for a fixed time, and the concentration of harmful substances is lower than in the original soil. As in the cleaning method and system of the previous application, in the cleaning of contaminated soil, it is related to surface cutting related to coarse particles such as special grinders and medicines as in the prior art. It is possible to cut the surface of coarse particles with extremely simple equipment using only general-purpose and inexpensive equipment and equipment without using equipment and equipment, and it is possible to enhance the cleaning effect, and the scale of the cleaning plant is small. And cleaning costs It can contribute to.

According to the contaminated soil cleaning system (1) of the present invention, the pump is a pump capable of sucking and transporting sand, and the piping is generally formed in a substantially L shape and can be raised vertically. It consists of piping and horizontal piping extended horizontally , and the slurry can be divided and dispersed in part or all of the piping within the piping and can repeatedly collide with the inner surface of the piping. A static mixer consisting of curved surface shape or uneven shape that changes the flow, or bending the pipe into a waveform that changes the flow of the slurry, or a combination of these is necessary for grinding the soil particles in the slurry provided the length secured between grinding time, the slurry pump, to ground the soil particles in the slurry through a pipe with a static mixer by continuous operation of the pump , As compared with the case of using a pipe (not having a static mixer such as described above) for conveying, to shorten the cleaning time to enhance the grinding effect of the soil particles. In this case, it formed into a substantially L-shape as a whole piping that is constituted by a vertical pipe and a horizontal direction of the pipe, a part or the whole of the pipe, ground static mixers of the soil particles in the slurry The length of the grinding time required for the installation is enough to make it possible to wash the slurry by passing it through a single pipe , eliminating the need for equipment for circulating the slurry, further downsizing the equipment as a whole , simplification To contribute to cost reduction.
According to the contaminated soil cleaning system (2) of the present invention, the pump is a pump capable of sucking and transporting sand, and the piping is generally formed in a substantially inverted U-shape or a substantially inverted J-shape, In all, the slurry can be divided and dispersed in the pipe and can be repeatedly collided with the inner surface of the pipe, the inner surface of the pipe is formed into a curved shape or uneven shape that changes the flow of the slurry, or the pipe is made into the slurry flow bending the waveform to give a change, or a static mixer comprising a combination of these is provided by continuous operation of the pump, the slurry was placed in a container vessel, a pump, is repeatedly circulated between the pipe with a static mixer, the slurry since grinding the soil particles in, for transporting (without a static mixer as described above) in comparison with the case of using a pipe, high attrition effect of soil particles The cleaning time can be shortened Te.
Further, this cleaning system (2) is a modification of the cleaning system of the prior application (Japanese Patent Application No. 2013-37057) by the present inventors (Japanese Patent Application No. 2013-37057). The coarse particles in the soil are removed from the slurry by classification after being circulated repeatedly between the container, pump, and piping, and circulated for a fixed time, and the concentration of harmful substances is lower than in the original soil. As in the cleaning method and system of the previous application, in the cleaning of contaminated soil, it is related to surface cutting related to coarse particles such as special grinders and medicines as in the prior art. It is possible to cut the surface of coarse particles with extremely simple equipment using only general-purpose and inexpensive equipment and equipment without using equipment and equipment, and it is possible to enhance the cleaning effect, and the scale of the cleaning plant is small. And washing It can contribute to a reduction of the bets.

The figure which shows the cleaning method and system of contaminated soil in a 1st embodiment of the present invention. The figure which shows the cleaning method and system of the contaminated soil in 2nd Embodiment of this invention. The figure which expands and shows the principal part of the method and system

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 also shows the method and system for cleaning contaminated soil according to the first embodiment of the present invention.
As shown in FIG. 1, in this cleaning method, a slurry of a mixture of soil contaminated with radioactive substances, harmful substances such as heavy metals (hereinafter simply referred to as contaminated soil) and water is sucked by a pump 12 and the slurry is used. The mixture is ground through a pipe 13 having a static mixer 14 for stirring, mixing and flowing.
And this cleaning method is realized by the cleaning system. This cleaning system includes a pump 12 for suctioning and feeding a slurry obtained by mixing contaminated soil and water, and a pipe 13 having a static mixer 14 for stirring, mixing and flowing the slurry sucked and fed by the pump 12. It consists of
In this case, the pump 12 is a pump capable of suction and transfer to the sand, and a submersible pump is used when installed in water and used, and a suction pump is used otherwise. Here, a submersible pump (sand pump) is adopted.
The pipe 13 has a material, diameter, and length suitable for circulating and conveying a slurry in which contaminated soil and water are mixed, and in particular, part or all of the pipe 13 is a static mixer 14. It has become. This static mixer 14 changes the flow of the slurry to allow active agitation and mixing, the inner surface of the pipe has a curved or uneven shape, or the pipe is corrugated, or a combination thereof. Configured In this case, the pipe 13 is formed in a substantially L-shape as a whole, and includes a vertical pipe 131 which is raised in the vertical direction and a horizontal pipe 132 which is extended in the horizontal direction. A static mixer 14 having a length that secures the grinding time required to grind the soil particles is provided over a wide range of the middle portion of the pipe 132. In this static mixer 14, the inner surface of the tube has a curved shape, in which a spiral blade is attached, and the slurry is divided and dispersed as it passes each spiral blade, and the guide of the spiral blade leads to The structure is such that stirring and mixing are performed positively in the pipe, such as flowing while repeatedly colliding with each part of the surface. In this case, the direction of twist may be partially reversed in each spiral blade, and the spiral blades may have different sizes and shapes, and in this way slurry Can make further changes in the flow of
The cleaning system comprises such an arrangement, wherein the slurry is continuously pumped by means of a pump 12 through a line 13 having a static mixer 14.

As shown in FIG. 1, in this cleaning method and system, the slurry is sucked by the pump 12 at the suction destination of the slurry in which the contaminated soil and water are mixed, and this slurry is passed through the pipe 13 with the static mixer 14 and polished. It is crushed and discharged at the end of this pipe 13 and sent to the next step. In addition, the continuous operation of the pump 12 continuously passes the slurry through the pipe with the static mixer 14. In this way, by passing the coarse particles in the slurry through the pipe 13, particularly in the static mixer 14, the slurry passes through each spiral blade without requiring power at this passage. Each time it is divided and dispersed, collision with each part of the inner surface of the tube is repeated by the guidance of a spiral blade, and furthermore, the action such as rubbing of coarse particles by such active stirring and mixing in the tube The heavily contaminated layer near the coarse particle surface is cut off at a very short constant cleaning time, compared to the case of heavily mixed and simply conveying (without static mixer) piping Crushing of the soil proceeds, the lumps of fine grains are broken up, and the fine grains that were firmly attached to the coarse grains are peeled off.
Then, in the next step after passing through the pipe 13 with the static mixer 14, the coarse particles in the soil are taken out of the slurry by classification, and the concentration of harmful substances is lower than in the original soil. Get the grain.

  As described above, according to the method and system for cleaning contaminated soil, the slurry is sucked by the pump 12 and is passed through the pipe 13 having the static mixer 14 for grinding, so that it can be used for transportation (static mixer (6) Compared to the case where piping is used, the grinding effect of soil particles can be enhanced and the washing treatment time can be significantly shortened, and the washing treatment time can be shortened to increase the washing treatment amount of contaminated soil. Can. Also, in this case, the pipe 13 having the static mixer 14 of such a length as to secure the grinding time necessary for grinding the soil particles is adopted, and the slurry is continuously supplied to the pipe 13 having the static mixer 14 by the continuous operation of the pump 12 By grinding through in a straight line, the washing process can be completed in one pipe passage without circulating the slurry, and the continuous treatment can greatly reduce the washing process time of the contaminated soil. Moreover, the installation for circulating a slurry, such as a water tank and piping for circulation, becomes unnecessary by doing in this way, the scale-reduction and simplification of an installation can be achieved, and it can contribute to the cost reduction.

FIGS. 2 and 3 also show a method and system for cleaning contaminated soil according to a second embodiment of the present invention.
As shown in FIG. 2, in this cleaning method, a slurry obtained by mixing contaminated soil and water is placed in a container (water tank) 21, the slurry in the container 21 is sucked by a pump 22, and the slurry is stirred and mixed. The slurry in the vessel 21 is milled and circulated between the vessel 21 and the pipe 23 having the static mixer 24 by grinding it through the pipe 23 having the static mixer 24 for fluidization and feeding back into the vessel 21. The grinding circulation of the slurry is repeated by continuous operation of the pump 22.
And this cleaning method is realized by the cleaning system. As shown in FIG. 3, this cleaning system comprises a container (water tank) 21 for containing a slurry in which contaminated soil and water are mixed, a pump 22 for sucking and delivering the slurry in the container 21, and agitating the slurry It has the static mixer 24 for mixing and making it flow, and it is comprised by the piping 23 which passes through the slurry drawn and sent out by the pump 22, and sends it back to the container 21.
In this case, the container 21 may be of any material, size, and shape suitable for circulating a predetermined amount of slurry in which contaminated soil and water are mixed. Here, the lower side of the circumferential surface of the container 21 is formed in a tapered shape, and is inclined toward the suction port side of the pump 22 installed near the center of the bottom of the container 21 The particles are easily collected near the pump 22. Note that the inclination of the container 21 is not essential, and may not be.
The pump 22 is a pump capable of suction and transfer to the sand, and a submersible pump may be employed when installed in water in the container 21, and a suction pump may be used when installed outside the container 21. Here, a submersible pump (sand pump) is adopted as the pump 22. The pump 22 is installed near the center of the bottom of the container 21.
The pipe 23 is made of a material, diameter, and length suitable for circulating and conveying a slurry in which contaminated soil and water are mixed, and in particular, part or all of the pipe becomes the static mixer 24. ing. The static mixer 24 changes the flow of the slurry to actively stir and mix, a curved surface or uneven shape is formed on the inner surface of the pipe, or the pipe itself is bent into a corrugated shape, or Composed of a combination. In this case, the piping 23 is generally formed in a substantially inverted U-shape or a substantially inverted J-shape, and the static mixer 24 is provided in the central straight piping portion. In this static mixer 24, the inner surface of the tube has a curved shape, in which a spiral blade is added, and the slurry is divided and dispersed as it passes each spiral blade, and the guide of the spiral blade leads to The structure is such that stirring and mixing are performed positively in the pipe, such as flowing while repeatedly colliding with each part of the surface. In this case, the direction of twist may be partially reversed in each spiral blade, and the spiral blades may have different sizes and shapes, and in this way slurry Can make further changes in the flow of
This cleaning system has such a configuration, and the slurry contained in the container 21 is repeatedly ground and circulated between the container 21, the pump 22, and the piping 23 having the static mixer 24 by continuous operation of the pump 22. There is.

As shown in FIG. 2, in this cleaning method and system, first, a slurry a, which is a mixture of contaminated soil and water, is placed in a container 21, and then the slurry a in the container 21 is aspirated by a pump 22, The slurry a in the container 21 is discharged from the end of the pipe 23 in the vessel 21 and returned to the original inside through the pipe 23 with the static mixer 24 from 22 and the pipe with the pump 21 and the static mixer 24 is returned. The circulation of the slurry a is repeated by continuous operation of the pump 22.
In this case, a predetermined amount of water may be injected into the container 21 and the contaminated soil may be sequentially introduced while operating the pump 22 to circulate water. In the case where a large diameter soot or a large foreign substance which can not pass through the pump 22 is mixed in the contaminated soil, the soot or the foreign substance is removed using a screen or the like. The contaminated soil thus introduced into the container 21 is immediately stirred together with water by the circulating action of water by the pump 22 to form a slurry a. When the feeding of the predetermined amount of contaminated soil to the container 21 is completed, the operation of the pump 22 is continued, and the slurry a is repeatedly circulated among the container 21, the pump 22, and the piping 23 with the static mixer 24. During circulation of the slurry a, the coarse particle fraction b in the slurry a settles in the lower part of the container 21 as shown in the figure, but this sedimentation can be achieved by using a pump 22 which can suction and convey the sand, such as a sand pump. The coarse particle fraction b can be circulated without any problem. In addition, since the lower side of the peripheral surface of the container 21 is tapered and inclined toward the pump 22, the coarse particle fraction b precipitated in the container 21 is easily collected near the pump 22, and the coarse particle fraction b is also smooth. Can be circulated. In this manner, the coarse particle fraction b in the slurry a passes through the pump 22 and the pipe 23 with the static mixer 24 many times, and during this passage, strong agitation by the blades of the pump 22, etc. The collision of the pipe 23 with the static mixer 24 with the wall, in particular, in the static mixer 24, the slurry splits and disperses as it passes through the spiral blades without requiring power, and the spiral blades The collision of each part of the inner surface of the tube is repeated by the guidance of the guide, and the mixture is vigorously mixed by the action such as rubbing of the coarse particles b by such appreciable stirring and mixing in the tube. The heavily polluted layer near the surface of the coarse particle b is cut with a considerably shorter constant cleaning time than in the case of the piping which does not have it, and the crushing of the soil Seen, mass fine fraction is understood, fine fraction which has been firmly attached to the coarse fraction is gradually peeled.
Then, the coarse particle fraction b of the soil is extracted from the slurry a which has been circulated for a certain period of time by classification to obtain a coarse particle fraction b in which the concentration of harmful substances is lower than that of the original soil.

As described above, according to the method and system for cleaning contaminated soil, the slurry contained in the container 21 is sucked by the pump 22 and the static mixer 24 for stirring and mixing the slurry and causing the slurry to flow is provided. The slurry in the container 21 is ground and circulated between the container 21, the pump 22 and the piping 23 having the static mixer 24 by grinding through the piping 23 and feeding back into the container 21, and the grinding circulation of the slurry is performed. Since it was made to repeat by continuous operation of pump 22, compared with the case where piping for conveyance (without a static mixer) is used, the grinding effect of soil particles is heightened and the washing processing time is shortened remarkably. The reduction of the cleaning time can increase the cleaning throughput of the contaminated soil.
In addition, this cleaning method and system is a modification of the cleaning method and system of the previous application (Japanese Patent Application No. 2013-37057) by the present inventors (Japanese Patent Application No. 2013-37057). , The container, the pump, and the piping are repeatedly circulated, and the coarse particles of the soil are taken out from the slurry by classification after being circulated for a fixed time, and the concentration of harmful substances is reduced compared to the original soil As it is common in terms of obtaining a portion, as in the cleaning method and system of the previous application, in the cleaning of contaminated soil, the surface cutting related to coarse particles such as special grinders and drugs as in the prior art is related It is possible to cut the surface of coarse particles with extremely simple equipment using only general-purpose and inexpensive equipment and equipment, without using equipment and equipment, and it is possible to enhance the cleaning effect, and the size of the cleaning plant is small. Scaling To have the advantage of being able to contribute to a reduction in the fine cleaning cost is a matter of course.

  In this embodiment, in the static mixer, a spiral blade is attached as a curved surface shape to the inner surface of the tube, and the slurry is divided and dispersed each time it passes through each spiral blade, and the spiral mixer is also used. The structure is such that stirring and mixing is performed actively in the pipe, such as flowing while repeatedly colliding with each part of the inner surface by guidance of the blades, but projecting pieces and protrusions are formed on the inner surface of the pipe as uneven shapes. The slurry may be divided and dispersed to flow, the flow direction of the slurry may be changed, or the slurry may be rotated (it may be reversed) to have a structure having an effect of repeating the collision inside the pipe. . In this case, the protruding pieces and the protrusions may have the same size and shape, or may have different sizes and shapes. Also, the piping itself may be further bent in a wavy shape (zigzag shape). Even with this configuration, the same effects as those of the above embodiment can be obtained.

  In this embodiment, although the case where the contaminated soil is directly cleaned by the method and system for cleaning contaminated soil according to the present invention has been described, this cleaning method and system are coarse particles of soil after cutting the contaminated soil with a cutting machine It can also be used for cleaning for removal of cutting powder adhering to the minute. In particular, in the case of radioactively contaminated soil, since the degree of removal of cutting powder from the coarse particles after cutting greatly affects the removal rate, the method and system of the present invention capable of efficiently removing cutting powder with a simple facility Is extremely effective.

12 pump 13 transport piping 131 vertical piping 132 horizontal piping 14 static mixer 21 vessel 22 pump 23 transport piping 24 static mixer a slurry b coarse particle fraction

Claims (4)

A method for cleaning contaminated soil in which radioactive substance-contaminated soil is cleaned by aspirating slurry mixed with radioactive substance-contaminated soil and water through a pipe and flowing it while stirring and mixing. ,
A pump capable of suction and transfer to the sand is adopted as the pump,
The pipe as a whole is formed into a substantially L shape, and is constituted by a vertical pipe which is vertically raised and a horizontal pipe which is horizontally extended, and a part or all of the pipe, The inner surface of the pipe is formed into a curved shape or an uneven shape that changes the flow of the slurry so that the slurry can be divided and dispersed in the pipe and repeatedly collides with the inner surface of the pipe, or the pipe can be flowed with the slurry Provide a static mixer consisting of bending, or a combination of these, to a length that changes the grinding time required for grinding the soil particles in the slurry .
The continuous operation of the pump passes the slurry through the pump and the pipe with the static mixer to grind particles in the slurry.
A method of cleaning contaminated soil characterized by The slurry mixed with the soil contaminated with radioactive material and water is placed in a container, the slurry in the container is sucked by a pump, and the slurry is sent through piping to the container to return the inside of the container. A method for cleaning contaminated soil, wherein the slurry is circulated between the container, the pump, and the piping, and the soil contaminated with radioactive material is cleaned by repeating circulation of the slurry.
A pump capable of suction and transfer to the sand is adopted as the pump,
The piping as a whole is formed in a substantially inverted U-shape or a substantially inverted J-shape, and the slurry can be divided and dispersed in the piping to a part or all of the piping and the piping can be repeatedly collided with the inner surface of the piping A static mixer is provided , which is formed in a curved shape or uneven shape that changes the flow of the slurry, or by bending the pipe into a waveform that changes the flow of the slurry, or a combination thereof .
By continuous operation of the pump, the slurry contained in the vessel is repeatedly circulated among the vessel, the pump, and the piping with the static mixer to grind the soil particles in the slurry.
A method of cleaning contaminated soil characterized by A pump for suctioning and delivering a slurry mixed with soil and water contaminated with radioactive material;
Piping for stirring, mixing and flowing the slurry sucked and sent out by the pump;
Equipped with
The pump is a pump capable of suction and transfer to the sand,
The piping is generally formed in a substantially L-shape, and includes a vertical piping that is vertically raised and a horizontal piping that is horizontally extended, and a part or all of the piping, The inner surface of the pipe is formed into a curved shape or an uneven shape that changes the flow of the slurry so that the slurry can be divided and dispersed in the pipe and repeatedly collides with the inner surface of the pipe, or the pipe can be flowed with the slurry a bend in the waveform to give a change, or provided to a length to ensure inter that grinding time required for grinding the soil particles of the static mixer in the slurry formed by combining these,
The continuous operation of the pump passes the slurry through the pump and the pipe with the static mixer to grind particles in the slurry.
Cleaning system for contaminated soil characterized by that. A container for containing a slurry of soil and water contaminated with radioactive material ;
A pump for suctioning and delivering the slurry in the container ;
Piping for passing the slurry sucked and sent out by the pump and sending it back to the container ;
Equipped with
The pump is a pump capable of suction and transfer to the sand,
The whole of the pipe is formed in a substantially inverted U-shape or a substantially inverted J-shape so that the slurry can be divided and dispersed in part or all of the pipe and can repeatedly collide with the inner surface of the pipe. There is provided a static mixer in which the inner surface of the pipe is formed into a curved shape or an uneven shape which changes the flow of slurry, or the pipe is bent into a waveform which changes the flow of slurry or a combination thereof.
By continuous operation of the pump, the slurry contained in the vessel is repeatedly circulated among the vessel, the pump, and the piping with the static mixer to grind the soil particles in the slurry.
Cleaning system for contaminated soil characterized by that.

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