JP6188018B2 - Cleaning and classification system and classification device - Google Patents

Description

  The present invention relates to a cleaning and classification system and a classification apparatus, and is suitable for application to, for example, soil cleaning and classification.

  Conventionally, soil classification is generally performed with a sieve. However, classification with a sieve has drawbacks such as clogging of the sieve, and a classification threshold (lower particle size limit value that can be classified) is limited to 75 μm. In addition, in the wet cleaning of soil, it is necessary to stir and classify in the same tank because stirring of the soil and the cleaning liquid is necessary for dispersion of the soil, and a stirring tank and a classification tank are required. Therefore, the apparatus required for cleaning and classification cannot be reduced in size.

  An apparatus for classifying particulate components contained in soil containing viscous soil, a stirring tank for stirring soil and water, and a waste water receiving mixed water containing clay after classification in the stirring tank. A water tank, a plurality of baffle plates provided in parallel in the stirring tank, and an air scatter for stirring the soil and water in the stirring tank by generating an upward flow along the plurality of baffle plates And the fine particles in the soil float and swell in the water, and become mixed water that is led to the adjacent drainage tank through the opening provided at the bottom of the baffle plate, and the drainage It is discharged to the outside of the drainage tank by the upward flow in the tank, and the sand and gravel in the soil move along the baffle plate by the upward flow, and classified to the bottom of the stirring tank by the difference in specific gravity of the sand and gravel. A soil classifier configured to be deposited is proposed That (see Patent Document 1.).

  Also, means for pulverizing contaminated soil, means for separating fine soil having a particle size of less than 2 mm from the crushed contaminated soil, purification having an average particle size of 0.5 to 10 mm and a particle size larger than that of the fine soil Means for supplying accelerated grains to fine-grained soil, washing tank for washing fine-grained soil mixed with purification-promoting grains, means for classifying purification-promoting grains and fine soil with a particle size of 74 μm or less from the washed fine-grained soil, classified Contaminated soil characterized by having a collection means for cleaning and promoting the purification promotion grains to the supply means, a coagulating sedimentation tank for receiving the classified fine soil, and means for dehydrating the fine grain soil from which the purification promotion grains and the fine soil have been separated A cleaning system has been proposed (see Patent Document 2).

  Further, in a hydraulic classifier that classifies mixed particles including fine particles and coarse particles to be classified under wet conditions, a cylinder provided in the vertical direction and a substantially uniform ascending liquid flow for classification are generated in the cylinder. A classifying liquid supply means, a mixed particle supply means for supplying the mixed particles almost uniformly into the cylindrical body facing the ascending liquid flow for classification, and fine particles classified with the ascending liquid flow for classification A classification liquid extracting means for substantially uniformly extracting from the cylinder, a coarse particle extracting means for discharging the classified coarse particles from the cylinder, the classification liquid supply means, and a classification liquid extracting means; There has been proposed a hydraulic classifier characterized by comprising a rectifying means comprising an inclined plate provided therebetween (see Patent Document 3).

  In addition, it consists of a compact structure in which a multistage treatment facility is housed in almost one case. The treated water from the first mouth is stirred and mixed in the polymer flocculant gel mass and a tank with a rotor, and then treated. Water is separated from large solids such as asphalt, and small solids are collected together, and the water separated from the solids passes between the three inclined plates in the ascending process, almost completely solids, There has been proposed a multi-stage water purification facility that separates floating substances and is discharged out of the system through an upper pipe (see Patent Document 4).

  Also, an apparatus for precisely classifying powder particles having various particle diameters, which is a tubular member extending in the length direction and having a rectangular cross section, and taking out at least two classified particles provided at predetermined intervals A tubular member having a mouth and inscribed in at least one rectifier, a carrier water injection device connected to one end of the tubular member so as to communicate with the tubular member so as to flow carrier water at a predetermined flow rate, and the powder A stirring liquid injection device connected to a part of the tubular member so as to communicate with the tubular member in order to merge the stirring liquid obtained by stirring the body particles in the liquid with the transport water at a predetermined flow rate. An apparatus has been proposed that flows in a laminar flow by passing through the rectifier in the tubular member together with the transport water (see Patent Document 5).

  Also, a static mixer configured by inserting a corrugated plate into a pipe line is known (see Patent Document 6).

Japanese Patent No. 3795059 Japanese Patent No. 4595099 JP-A-6-154643 US Pat. No. 5,547,569 JP-A-9-206627 US Patent No. 5380088

  As described above, in the conventional classification device or soil cleaning device that classifies soil using a sieve, clogging of the sieve occurs, the classification threshold is limited to 75 μm, and the device cannot be downsized. There was a problem.

  Therefore, the problem to be solved by the present invention is that the system can be reduced in size by being able to stir and classify the soil, more generally, mixed particles having a particle size distribution in one container. In addition, a cleaning and classification system capable of continuously adjusting a classification threshold and a classification device suitable for use in the cleaning and classification system are provided.

In order to solve the above problems, the present invention provides:
Having a classifier and a settling device arranged in parallel with each other;
The classification device is
A first container;
The mixed particles having a particle size distribution and the cleaning liquid provided in the first container are supplied, and the mixed particles and the cleaning liquid are stirred to generate a solid-liquid mixed phase flow in which the mixed particles and the cleaning liquid are mixed. A stirring layer for,
A rectifying layer comprising a wavy static mixer for providing a uniform flow of the solid-liquid mixed phase flow supplied from the stirring layer, provided in the upper stage of the stirring layer,
An angle Ψ (0 degree <Ψ <90 degrees) with respect to the horizontal direction for classifying the mixed particles, which is provided in the upper stage of the rectifying layer and supplied with the solid-liquid mixed phase flow passing through the rectifying layer A classification layer having a plurality of inclined pipelines,
The settling device
A second container;
An angle Θ (0 ° <Θ <90 °) with respect to the horizontal direction for settling and agglomerating particles in the solid-liquid mixed phase flow passing through the classification layer provided in the second container The cleaning and classification system has a laminated inclined plate in which a plurality of inclined flat plates are laminated with a space therebetween, and the solid-liquid mixed phase flow has a sedimentation layer supplied to the side surface of the laminated inclined plate.

  To the stirring layer, mixed particles having a particle size distribution and cleaning liquid for cleaning and classification are supplied from the outside, and the mixed particles and cleaning liquid are stirred and mixed. In the stirring layer, a stirring pump may be provided to stir the mixed particles and the cleaning liquid, or the mixed particles may be stirred by the force of water flow by a high-pressure jet, or these may be used in combination. Washing of the mixed particles is performed mainly in the process of stirring and mixing in the stirring layer. In the stirring layer, particles having a large particle size left by classification out of the mixed particles having a particle size distribution settle and deposit on the bottom, and the particles thus deposited are removed from the stirring layer to the outside of the first container. They may be taken out and collected. The particles thus recovered may be supplied again to the stirring layer for cleaning again.

  The solid-liquid mixed phase flow supplied from the stirring layer is supplied as an upward flow to the rectifying layer composed of the wavy static mixer, and is rectified by repeatedly mixing the solid-liquid mixed phase flow in the process of passing through the rectifying layer. It is converted into a style. Here, the wavy static mixer is a static mixer constituted by a wavy plate (see Patent Document 6). Washing of the mixed particles is also performed in the process of rectification in the rectification layer.

  The classification layer is typically a structure having a plurality of cylindrical holes inclined at an angle Ψ with respect to the horizontal direction or a plurality of plates inclined at an angle Ψ with respect to the horizontal direction and stacked with a space between each other. It consists of a laminated inclined plate. In a structure having a cylindrical hole, the cylindrical hole constitutes a pipe line. The cross-sectional shape of the cylindrical hole is selected as necessary, and specifically, for example, a circle, an ellipse, a triangle, a quadrangle, a pentagon, a hexagon, and the like. Triangles, squares or hexagons that can be arranged in a packed arrangement are preferred. Since classification can be performed more easily when the flow velocity in the pipeline is smaller, the thickness of the partition wall between the cylindrical holes is preferably sufficiently small. Further, in the laminated inclined plate, a space between adjacent plates constitutes a pipe having a rectangular cross section. Also in this case, preferably, the thickness of the plate serving as the partition wall is made sufficiently small. Ψ and the lengths of these pipes are appropriately selected according to the classification threshold, in other words, the particle size of the particles that do not pass through these pipes. The inclination direction of the classification layer pipe line is not particularly limited, and is selected as necessary. For example, the inclination line Ψ is inclined with respect to the horizontal direction so that the settling device side becomes higher, or the opposite side to the settling device is The angle ψ is inclined with respect to the horizontal direction so as to be higher.

  In the solid-liquid mixed phase flow supplied to the classification layer, if the turbulent diffusion of particles occurs, the efficiency of the classification is reduced.To prevent this and perform classification by the classification layer efficiently, the cleaning and classification system is Preferably, it further has a laminar flow layer provided between the rectifying layer and the classification layer for converting the solid-liquid mixed phase flow that has passed through the rectifying layer into a laminar flow. This laminar flow layer typically comprises a structure having a plurality of vertical cylindrical holes. In this structure, a cylindrical hole forms a pipe line. Further, since particles having a large particle diameter can be removed by the laminar flow layer, blockage of the classification layer pipe line by particles having a large particle diameter can be prevented.

  In the solid-liquid mixed phase flow that has passed through the classification layer, particles having a small particle size remain among the mixed particles, but in order to efficiently settle these particles in the settling device, the particles have passed through the classification layer. It is desirable to increase the particle size by promoting the agglomeration of these particles as much as possible before the solid-liquid mixed phase flow is fed to the settling device. Therefore, the cleaning and classification system preferably further includes an aggregation promoting layer provided to connect the first container and the second container to each other. This aggregation promoting layer has a plurality of pipelines inclined at an angle Ω (0 ° <Ω ≦ 10 °) with respect to the horizontal direction so that the horizontal direction or the second container side is lowered. In this case, the solid-liquid mixed phase flow that has passed through the classification layer is supplied to one end of the aggregation promoting layer, and is supplied from the other side surface to the second container. Specifically, the agglomeration promoting layer is, for example, a laminated plate in which a plurality of horizontal plates are laminated with a space between each other, and an angle Ω (0 degree <0 degrees with respect to the horizontal direction so that the second container side is lowered Ω ≦ 10 degrees) A laminated inclined plate in which a plurality of inclined plates are laminated at intervals, a structure having a plurality of horizontal cylindrical holes, or a horizontal direction so that the second container side is lowered. And a structure having a plurality of cylindrical holes inclined at an angle Ω. Alternatively, the aggregation promoting layer has, for example, a gable roof shape inclined at an angle Φ (0 ° <Φ <90 °) with respect to the horizontal direction downward from the top in the direction of the central axis of the aggregation promoting layer to both sides. An angle Φ (0 ° <Φ <90 °) with respect to the horizontal direction downward from the top in the direction of the central axis of the laminated inclined plate or the aggregation promoting layer in which a plurality of plates are laminated with a space therebetween Laminated inclined plate in which a plurality of gable roof-shaped plates that are inclined and inclined at an angle Ω (0 ° <Ω ≦ 10 °) with respect to the horizontal direction are stacked so as to be spaced apart from each other so that the second container side is lowered Consists of. If necessary, on the plate at the bottom of the duct, a vertical plate extending in the direction perpendicular to the central axis of the aggregation promoting layer and having a height in the middle of the duct is arranged on the central axis of the aggregation promoting layer. May be provided periodically or non-periodically in the direction, so that particles can be trapped in the region between the vertical plates and promote the sedimentation of the particles and thus the aggregation Can do.

  The solid-liquid mixed phase flow that has passed through the classification layer is not necessarily uniform when it is supplied to the settling device. Therefore, the cleaning and classification system preferably includes a rectifying layer comprising a wave-like static mixer between the classification layer and the sedimentation device, or between the classification layer and the aggregation promotion layer when an aggregation promotion layer is provided. Also have. By carrying out like this, the solid-liquid mixed phase flow supplied to a sedimentation apparatus from a classification layer can be made into a uniform flow, and sedimentation of particle | grains can be performed efficiently.

  The mixed particles having a particle size distribution may basically be any material, and the material is not limited, but specifically, for example, mixed particles composed of particles of various materials other than soil, Mixed particles composed of soil and particles of various materials other than soil. An example of mixed particles composed of particles of various materials other than soil is a mixed particle composed of carbon particles having a small particle diameter and gypsum particles having a particle diameter larger than the carbon particles. The cleaning liquid is typically water, but it may be a solution in which other substances (various liquids or gases such as ozone or carbon dioxide) are dissolved in water, or various solvents other than water, For example, various organic solvents (alcohol, acetone, toluene, etc.) may be used.

In addition, this invention
A first container;
The mixed particles having a particle size distribution and the cleaning liquid provided in the first container are supplied, and the mixed particles and the cleaning liquid are stirred to generate a solid-liquid mixed phase flow in which the mixed particles and the cleaning liquid are mixed. A stirring layer for,
A rectifying layer comprising a wavy static mixer for providing a uniform flow of the solid-liquid mixed phase flow supplied from the stirring layer, provided in the upper stage of the stirring layer,
An angle Ψ (0 degree <Ψ <90 degrees) with respect to the horizontal direction for classifying the mixed particles, which is provided in the upper stage of the rectifying layer and supplied with the solid-liquid mixed phase flow passing through the rectifying layer A classification device having a classification layer having a plurality of inclined pipelines.

  In the invention of the classifying device, what has been described in relation to the invention of the cleaning and classifying system is valid. For example, the classification layer is typically a structure having a plurality of cylindrical holes inclined at an angle Ψ with respect to the horizontal direction or a plurality of plates inclined at an angle Ψ with respect to the horizontal direction with a space between each other. It consists of the laminated inclination board made. The classifier preferably further includes a laminar flow layer provided between the rectifying layer and the classifying layer for converting the solid-liquid mixed phase flow that has passed through the rectifying layer into a laminar flow.

  According to the present invention, mixed particles having a particle size distribution, for example, soil agitation and classification can be performed in one container, so that the system can be miniaturized and the pipes constituting the classification layer can be reduced. By adjusting the height and length, the classification threshold can be continuously adjusted.

1 is a sectional view showing a cleaning and classification system according to a first embodiment of the present invention. 1 is a perspective view showing a cleaning and classification system according to a first embodiment of the present invention. It is a basic diagram for demonstrating the structure of the wavy static mixer which comprises the rectification | straightening layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the structure of the laminar flow layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the structure of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the structure of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the principle of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the principle of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the principle of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the principle of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the principle of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a basic diagram for demonstrating the principle of the classification layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. It is sectional drawing which shows the structure of the sedimentation layer of the sedimentation apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. 1 is a perspective view showing a specific first configuration example of a cleaning and classification system according to a first embodiment of the present invention. FIG. It is a perspective view which shows the specific 2nd structural example of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a partially expanded view for demonstrating the supply method of the soil and water to the stirring layer of the washing | cleaning and classification system shown in FIG. It is a perspective view which shows the specific 3rd structural example of the washing | cleaning and classification system by 1st Embodiment of this invention. It is a drawing substitute photograph which shows the classification apparatus used in the experiment conducted in order to verify the function of each layer of the classification apparatus of the washing | cleaning and classification system by 1st Embodiment of this invention. FIG. 19 is a drawing-substituting photograph showing an appearance of a solid-liquid mixed phase flow at a specific position of the classifier shown in FIG. It is a drawing substitute photograph which shows the fine-grained sand plume which flows under the classification layer of the classification apparatus shown in FIG. 2 is a drawing-substituting photograph showing a cleaning and classification system according to Example 1. FIG. It is a basic diagram which shows the measurement result of SS in each measuring point of what does not use a sedimentation apparatus in the washing | cleaning and classification system by Example 1, and the washing | cleaning and classification system by Example 1. FIG. It is a basic diagram which shows the measurement result of SS in the measurement points 1 and 2 of FIG. It is a basic diagram which shows the measurement result of the particle size distribution of a raw soil when performing washing | cleaning and classification of soil using the washing | cleaning and classification system by Example 1, the particle size distribution in a classification apparatus, and the particle size distribution in a sedimentation apparatus. is there. It is a basic diagram which shows the particle size distribution of the raw soil which performs washing | cleaning and classification of radioactively contaminated soil using the washing | cleaning and classification system by Example 1, and the particle size distribution of the soil after classification. It is a basic diagram which shows the external appearance of the solid-liquid mixed-phase flow in each layer of a classification apparatus when the radioactive contamination soil is wash | cleaned and classified using the washing | cleaning and classification system by Example 1. FIG. It is sectional drawing which shows the washing | cleaning and classification system by 2nd Embodiment of this invention. It is sectional drawing which shows the washing | cleaning and classification system by 3rd Embodiment of this invention. It is sectional drawing which shows the washing | cleaning and classification system by 4th Embodiment of this invention. It is sectional drawing which shows the specific 1st structural example of the aggregation promotion layer in the washing | cleaning and classification system by 4th Embodiment of this invention. It is sectional drawing which shows the specific 2nd structural example of the aggregation promotion layer in the washing | cleaning and classification system by 4th Embodiment of this invention. It is the top view, sectional drawing, and partial enlarged view which show the specific 3rd structural example of the aggregation promotion layer in the washing | cleaning and classification system by 4th Embodiment of this invention. It is a perspective view which shows the specific 4th structural example of the washing | cleaning and classification system by 4th Embodiment of this invention. It is a perspective view which shows the specific 5th structural example of the washing | cleaning and classification system by 4th Embodiment of this invention. It is a perspective view which shows the specific 6th structural example of the washing | cleaning and classification system by 4th Embodiment of this invention. It is a perspective view which shows the structure of the washing | cleaning and classification system by Example 2. FIG. 6 is a cross-sectional view showing a configuration of an aggregation promoting layer in a cleaning and classification system according to Example 2. 6 is a cross-sectional view showing another configuration of the aggregation promoting layer in the cleaning and classification system according to Embodiment 2. FIG. It is a basic diagram which shows the measurement result of SS in the measuring points 1 and 2 after performing washing | cleaning and classification by the washing | cleaning and classification system by Example 2. FIG. It is sectional drawing which shows the washing | cleaning and classification system by 5th Embodiment of this invention.

  Hereinafter, modes for carrying out the invention (hereinafter referred to as “embodiments”) will be described with reference to the drawings.

<First Embodiment>
[Cleaning and classification system]
1 and 2 show a cleaning and classification system according to a first embodiment. Here, FIG. 1 is a sectional view, and FIG. 2 is a perspective view. As shown in FIGS. 1 and 2, the cleaning and classification system has a classification device 10 and a sedimentation device 20 arranged in parallel with each other.

  The classification device 10 includes a container 11 having an open top, a stirring layer 12 provided at the bottom of the container 11, a rectifying layer 13 provided in the upper stage of the stirring layer 12, and a layer provided in the upper stage of the rectifying layer 13. It has a fluidized layer 14 and a classification layer 15 provided on the upper stage of the laminar fluidized layer 14. The shape of the container 11 is not particularly limited, but typically has a substantially rectangular parallelepiped shape. The sizes of the container 11, the stirring layer 12, the rectifying layer 13, the laminar flow layer 14, and the classification layer 15 are not particularly limited, and are selected as necessary. As an example of these sizes, the width and depth of the container 11, the stirring layer 12, the rectifying layer 13, the laminar flow layer 14 and the classification layer 15 are all 20 to 40 cm, the height of the container 11 is 60 to 100 cm, The stirring layer 12 has a height of 10 to 20 cm, the rectifying layer 13 has a height of 20 to 40 cm, the laminar flow layer 14 has a height of 5 to 10 cm, and the classification layer 15 has a height of 10 to 20 cm.

  The agitation layer 12 is a target for washing and classification, in which mixed particles having a particle size distribution such as soil and a washing liquid such as water are agitated and mixed to generate a solid-liquid mixed phase flow in which the mixed particles and the washing liquid are mixed. Is. The stirring particles 12 can be supplied with mixed particles and cleaning liquid from the outside of the container 11. Specifically, for example, a cleaning material introduction pipe (not shown) is connected through an opening (not shown) provided in a side wall of the container 11 around the stirring layer 12. The mixed particles to be fed into a washing material inlet (not shown) provided at one end can be supplied into the stirring layer 12 from the washing material introduction pipe. Further, for example, a cleaning liquid introduction pipe (not shown) is connected to the side wall of the container 11 around the stirring layer 12, and the cleaning liquid can be supplied into the stirring layer 12 from the cleaning liquid introduction pipe. ing. Alternatively, for example, a cleaning material introduction pipe is connected to the cleaning liquid introduction pipe from above before the container 11 and a high-pressure jet of the cleaning liquid is supplied from the cleaning liquid introduction pipe, thereby sucking mixed particles from the cleaning material introduction pipe and mixing them. The particles and the cleaning liquid may be supplied to the inside of the stirring layer 12. The mixed particles and the cleaning liquid thus supplied into the stirring layer 12 are stirred and mixed by, for example, a stirring pump (not shown) provided in the stirring layer 12, and are a solid-liquid mixed phase flow composed of the mixed particles and the cleaning liquid. Is generated. When a cleaning material introducing tube is connected to the cleaning solution introducing tube from above before the container 11 and a high pressure jet of the cleaning solution is supplied from the cleaning solution introducing tube, a stirring pump may or may not be provided inside the stirring layer 12. In any case, the mixed particles and the cleaning liquid can be stirred and mixed in the stirring layer 12. The particles left by the classification by the classification layer 14 settle and deposit on the bottom of the stirring layer 12, and the particles thus deposited are taken out from the deposit extraction port provided in the bottom of the stirring layer 12 (see FIG. (Not shown) can be taken out to the outside.

  The rectifying layer 13 is for making the solid-liquid mixed phase flow stirred and mixed in the stirring layer 12 and discharged in the vertical direction uniform in a horizontal plane, and is composed of a wave-like static mixer. This solid-liquid mixed phase flow is repeatedly stirred while passing through the wavy static mixer from the bottom to the top, rectified in the process, and converted into a uniform flow after the passage. An example of the wavy static mixer that constitutes the rectifying layer 13 will be described. FIG. 3A shows an example of the corrugated plate 16. As shown in FIG. 3A, a rectangular portion indicated by a one-dot chain line is cut out from the corrugated plate 16. Each side of the rectangular corrugated plate 16 is inclined 45 degrees with respect to the direction in which the wave peaks and valleys extend. As shown in FIG. 3B, a plurality of rectangular corrugated plates 16 cut out in this way are overlaid so that the directions in which the wave peaks and valleys extend are orthogonal to each other. The size and the number of corrugated plates 16 to be superimposed are appropriately determined according to the size of the container 10 and the like. Then, as shown in FIG. 3C, the rectangular parallelepiped corrugated sheet laminates 13 a, 13 b, and 13 c on which the corrugated sheets 16 are overlapped in this way are arranged in parallel to form a rectifying layer 13. However, the number of corrugated laminates constituting the rectifying layer 13 may be one, two, or four or more. The size of the corrugated plate 16, the overall thickness and the wave pitch are selected as necessary. For example, the size is 20 cm × 20 cm, the overall thickness is 9 mm, and the wave pitch is 32 mm. . An example of the thickness of the plate material constituting the corrugated plate 16 is 0.7 mm.

  The laminar flow layer 14 is for converting a uniform solid-liquid mixed phase flow discharged vertically upward from the rectifying layer 13 into a laminar flow in the vertical direction. The laminar flow layer 14 is designed such that the solid-liquid mixed phase flow is a low Reynolds number flow, and has a pipe line composed of a plurality of vertical cylindrical holes so that there is no turbulent diffusion and particles do not diffuse. Consists of. FIG. 4A shows an example of a cross-sectional structure of the laminar flow layer 14. As shown in FIG. 4A, the laminar flow layer 14 is composed of a structure in which a plurality of pipe lines composed of vertical cylindrical holes 14b separated by a partition wall 14a are arranged in a two-dimensional plane. 4B, C and D show examples of plan views of the laminar flow layer 14. FIG. In the example shown in FIG. 4B, a pipe line including a cylindrical hole 14b having a regular triangular cross section separated by a partition wall 14a is provided in a two-dimensional plane. In the example shown in FIG. 4C, a pipe line formed of a cylindrical hole 14b having a square cross section separated by a partition wall 14a is provided in a two-dimensional plane. In the example shown in FIG. 4D, a pipe line formed of a cylindrical hole 14b having a hexagonal cross section separated by a partition wall 14a is provided in a two-dimensional plane.

In the laminar flow layer 14, specifically, for example, the Reynolds number Re of the flow in the cylindrical hole 14b is designed so as to satisfy Re <2300, which is a condition that the circular flow becomes a laminar flow. The flow rate Q, the internal diameter of the container 11 and the hole 14b (equivalent diameter) each h _A, When h _a, the Reynolds number Re _a is within each Reynolds number Re _A and holes 14b in the container 11
It becomes. Here, the cross-sectional area of the partition of the partition wall 14a of the hole 14b is set to be negligible in comparison to the cross-sectional area of the hole 14b, and a ^{_{h A 2 = Nh a 2 (}} N number of holes 14b). Therefore, the Reynolds number Re _a of the flow passing through the hole 14b is N ^−1/2 times the Reynolds number Re _A of the flow passing through the container 11, and laminar flow is possible. For example, if h _A = 1 m and h _a = 4 mm, Re _a is 4 mm / 1 m = 0.004 times Re _A. Further, when the lower limit value of the Reynolds number Re _a of the flow passing through the hole 14b is set to 2000, the Reynolds number Re _A of the flow passing through the container 11 becomes 2000 × (1 m / 4 mm) = 500,000. The upper limit value of the flow rate is determined.

  The classification layer 15 is for classifying the mixed particles of a uniform laminar solid-liquid mixed phase flow discharged vertically upward from the laminar flow layer 14 and is designed based on the well-known principle described below. The That is, the settling time of particles having a specific gravity greater than the specific gravity of the cleaning liquid (for example, particles having a specific gravity greater than 1 when the cleaning liquid is water) becomes shorter as the settling distance becomes shorter. It is promoted by installing. Therefore, the sedimentation particles can be effectively captured when the inclined pipeline is spatially densely installed in the cleaning liquid. FIG. 5A shows an example of a cross-sectional structure of the classification layer 15. As shown in FIG. 5A, the classification layer 15 is formed of a structure in which a plurality of inclined pipe lines each formed of a cylindrical hole 15b inclined with respect to the horizontal direction and separated by a partition wall 15a are arranged in a two-dimensional plane. 5B, C and D show examples of plan views of the classification layer 15. FIG. In the example shown in FIG. 5B, a pipe line formed of cylindrical holes 15b having a regular triangular cross section separated by a partition wall 15a is provided in a two-dimensional plane. In the example shown in FIG. 5C, a pipe line made of a cylindrical hole 15b having a square cross section separated by a partition wall 15a is provided in a two-dimensional plane. In the example shown in FIG. 5D, a pipe line formed of a cylindrical hole 15b having a hexagonal cross section separated by a partition wall 15a is provided in a two-dimensional plane. FIG. 6A shows another example of the sectional structure of the classification layer 15. As shown in FIG. 6A, the classification layer 16 has a plurality of inclined pipelines arranged in a two-dimensional plane composed of cylindrical holes 15b having a rectangular sectional shape inclined with respect to the horizontal direction and separated by a partition wall 15a. Consists of a structure. FIG. 6B shows a plan view of the classification layer 15. The inclination angle of these inclined pipes with respect to the horizontal direction is Ψ (0 degree <Ψ <90 degrees). The inclination direction of these inclined pipes is selected as necessary. For example, the inclination pipe is inclined by an angle Ψ with respect to the horizontal direction so that the settling apparatus 20 side becomes higher, or the opposite side to the settling apparatus 20 becomes higher. The angle ψ is inclined with respect to the horizontal direction.

The principle of classification by the classification layer 15 will be described in detail with reference to FIG. FIG. 7 shows a state in which particles having a specific gravity larger than the specific gravity of the cleaning liquid advect upward due to the upward flow in the inclined pipe line composed of holes inclined with respect to the horizontal direction. As shown in FIG. 7, the origin is the lower end of the inlet of the inclined pipeline, the coordinate axis X (t) in the direction along the inclined pipeline with time represented by t, and the coordinate axis Z (t) in the direction perpendicular to the inclined pipeline. And the position of the particle in the inclined pipe is represented as (X (t), Z (t)). The pipe length of the inclined pipe is l. Gravity mg (m is the mass of the particle and g is the acceleration of gravity) acts on the particles in the vertical direction. The particles settle on the bottom surface of the inclined pipe when going up a distance L along the inclined pipe. The settled particles slide along the bottom surface of the inclined pipe and are discharged from the lower end inlet. When the Reynolds number of the particle is sufficiently smaller than 1, the particle trajectory can be predicted as follows according to Stokes' resistance law.
Here, γ is the specific gravity of the particles, φ is the particle diameter (particle outer diameter), ν is the kinematic viscosity coefficient of the fluid, U _m is the average flow velocity, and c is the volume ratio of the particles. Further, f (c) is a reduction rate of the settling velocity with an increase in particle concentration. When one particle settles without being influenced by surrounding particles, f (c) = 1, and the influence of surrounding particles. F (c) <1 when settling after receiving. The distance (upward run length) L until the particles settle on the bottom surface of the inclined pipe line can be obtained using Equation (2). That is, by solving equation (2) and obtaining X (t) = L when Z (t) = 0,
It becomes. Here, Ψ is the inclination angle of the inclined pipe from the horizontal direction (0 degree <Ψ <90 degrees), h is the height of the pipe, n is 6 in the two-dimensional Poiseuille flow, and 8 in the circular pipe Poiseuille flow. . From equation (3), the maximum particle size of the particles that do not pass through the inclined conduit is determined as a function of the conduit height h and the run-up length L. According to this principle, by making the inclination angle Ψ of the inclined pipe line variable, it is possible to easily and continuously adjust the threshold value of the particles to be classified, in other words, the lower limit value of the classifiable particle size.

8, FIG. 9 and FIG. 10 are the run-up length L calculated from the prediction formula (3). However, U _m = 0.52 cm / s, γ = 2.7, ν = 0.01 cm ² / s, c = 0, f (c) = 1, and the equivalent diameter h _A of the container 11 was 40 cm. From FIG. 8, for example, in the case of an inclined pipe having a height (h) of 2.54 mm and a length (L) of 10 cm, when a flow rate Q is 50 L / min, a particle having a particle diameter φ of 30 μm is passed. In order to prevent this, the inclination angle ψ needs to be about 80 degrees or less, and for particles having a particle diameter φ of 20 μm, it needs to be 63 degrees or less. Further, from FIG. 9, for example, in an inclined pipe having a pipe height (h) of 2.54 mm and a length (L) of 10 cm, when the flow rate Q is 180 L / min, particles having a particle diameter φ of 50 μm In order to prevent the particles from passing through, the inclination angle Ψ needs to be approximately 77 degrees or less, and for particles having a particle diameter φ of 30 μm, it is necessary to be 52 degrees or less. Further, from FIG. 10, for example, in an inclined pipe having a pipe height (h) of 3 mm and a length (L) of 10 cm, when a flow rate Q is 180 L / min, a particle having a particle diameter φ of 50 μm is passed. In order to prevent this, the tilt angle Ψ needs to be about 72 degrees or less. On the other hand, with respect to the inclination angle Ψ of the inclined pipe, in order that the particles settled on the bottom surface of the inclined pipe slide on the bottom surface and are discharged from the inlet of the pipe, the friction coefficient μ between the bottom surface and the particles is μ < It is necessary to satisfy tan Ψ. However, a decrease in the value of the friction coefficient μ can be expected due to mechanical vibration of the pump or the like.

By the way, Re = Uh / ν = (h / h _A ) Re _A where Reynolds number of the flow passing through the inclined pipe is Re. 11, when the critical Reynolds number Re _c is 1000, the Reynolds number Re of the flow through the angled conduit is one that sought h when becomes Re _c relative to the flow rate Q. From FIG. 11, h when the Reynolds number Re of the flow through the angled conduit is Re _c it is seen that the flow rate Q becomes higher increases small.

FIG. 12 shows L / h calculated from the prediction formula (3) when the particle diameter is φ = 5 μm or 10 μm. However, U _m = 0.52 cm / s, γ = 2.7, ν = 0.01 cm ² / s, c = 0, f (c) = 1, the equivalent diameter h _A of the container 11 = 40 cm, and the flow rate Q is 50 L / min. From FIG. 12, for example, in order to prevent particles having φ = 5 μm from passing, it is understood that L / h needs to be about 400 or more when Ψ = 40 degrees. For example, considering the case where only the viscosity component is separated from the soil by classification, it is necessary to set the classification threshold to about 5 μm, which is the minimum diameter of silt, which is effective in such a case.

  The settling device 20 includes a container 21 having an open top, and a settling layer composed of stacked inclined plates 22 and 23 provided in two upper and lower stages inside the container 21. However, the number of steps of the laminated inclined plate provided inside the container 21 is not particularly limited, and may be one or three or more. The inclined plates constituting the laminated inclined plates 22 and 23 are inclined at an angle Θ (0 ° <Θ <90 °) with respect to the horizontal direction. The shape of the container 21 is not particularly limited, but typically has a substantially rectangular parallelepiped shape. The size of the container 21 and the laminated inclined plates 22 and 23 is not particularly limited, and is selected as necessary. As an example of these sizes, the height of the container 21 is 60 to 100 cm, the width and depth are 20 to 40 cm, the height of the laminated inclined plates 22 and 23 is 20 to 40 cm, and the width and depth are 15 to 35 cm. is there. In this case, one side wall of the container 21 is in contact with one side wall of the container 11 of the classifier 10, but the present invention is not limited to this. For example, rectangular openings 31 are provided on the side walls of the containers 11 and 21 that are in contact with each other. The lower side of the opening 31 is at least as high as the classification layer 15. The laminated inclined plates 22 and 23 are composed of a plurality of inclined plates laminated at intervals. The inclination direction of the inclined plates constituting the laminated inclined plates 22 and 23 is a direction perpendicular to the supply direction of the solid-liquid mixed phase flow after classification supplied from the classification layer 15, and for example, the front side of FIG. It is inclined to. The solid-liquid mixed phase flow after classification supplied from the classification layer 15 enters the inside from the side surface of the upper laminated inclined plate 23. 13A and 13B show an example of the positional relationship between the container 21 and the laminated inclined plates 22 and 23. FIG. As shown in FIG. 13B, the inclined plate 22a constituting the laminated inclined plate 22 and the inclined plate 23a constituting the laminated inclined plate 23 are inclined at an angle Θ (0 ° <Θ <90 °) with respect to the horizontal direction. . As shown in FIGS. 13A and 13B, in this example, a gap is provided between the container 21 and the laminated inclined plates 22 and 23. The solid-liquid mixed phase flow after classification in the classification layer 15 first flows along the inclined plate 23a through the gap 23b between the inclined plate 23a and the inclined plate 23a of the laminated inclined plate 23, and then the laminated inclined plate 22 The gap 22b between the inclined plate 22a and the inclined plate 22a flows along the inclined plate 22a. In the process, particles settle and deposit on the inclined plates 23a, 22a, and slides down the inclined plates 23a, 22a to finally In particular, it goes out of the laminated inclined plate 22. The solid-liquid mixed phase flow that has passed through the laminated inclined plates 22 and 23 rises through a gap provided between the container 21 and the laminated inclined plates 22 and 23, and at the time when the laminated inclined plate 23 is exceeded, FIG. As shown in FIG. 5, the liquid flows out to the outside through a weir-shaped discharge port 32 provided on the wall surface of the container 21. For example, the solid-liquid mixed phase flow that has flowed out in this manner is recovered by a recovery system, the cleaning liquid is reused as necessary, and the particle components are recovered. If necessary, at least a part of at least one of the inclined plates 22a and 23a constituting the laminated inclined plates 22 and 23, for example, the surfaces of the inclined plates 22a and 23a may be configured with magnets. By constituting at least a part of the inclined plates 22a and 23a with magnets in this way, when the particles show paramagnetism, the particles are magnetized by a magnetic field generated by the magnets, so that the particles are attracted to the inclined plates 22a and 23a by a magnetic force. It is done. For this reason, the particles easily settle on the inclined plates 22a and 23a. Thus, the particles settled on the inclined plates 22a and 23a aggregate and slide down the inclined plates 22a and 23a. This technique is effective, for example, when clay containing cesium ions contained in radioactively contaminated soil exhibits paramagnetism and is removed. In particular, it is desirable that the inclined plate 23a of the upper layered inclined plate 23 into which the solid-liquid mixed phase flow first flows, and in particular the upper inclined plate 23a, are constituted by magnets.

[How the cleaning and classification system works]
Next, an operation method of the cleaning and classification system configured as described above will be described.

  First, mixed particles and cleaning liquid having a particle size distribution are supplied to the stirring layer 12 from the outside of the container 11 of the classifier 10, these mixed particles and cleaning liquid are stirred and mixed, and a solid-liquid mixed phase composed of these mixed particles and cleaning liquid Generate a flow. This solid-liquid mixed phase flow is in a turbulent state. Washing of the mixed particles is performed mainly in the process of stirring and mixing in the stirring layer 12. This solid-liquid mixed phase flow is carried upstream by the cleaning liquid, supplied to the rectifying layer 13 formed of a wave-like static mixer, and converted into a uniform flow in the process of passing through the rectifying layer 13. The cleaning of the mixed particles is also performed in the process of rectification in the rectifying layer 13. The solid-liquid mixed phase flow thus made uniform is supplied to the laminar flow layer 14 and becomes a laminar flow in the process of passing through the laminar flow layer 14, and particles having a large sedimentation velocity are classified. Large particle components are removed. The solid-liquid mixed phase flow converted into the laminar flow in the laminar flow layer 14 is supplied to the classification layer 15, and a predetermined particle component is classified in the process of passing through the classification layer 15. The threshold for classification by the classification layer 15 can be adjusted by the height h of the pipe line of the classification layer 15, in other words, the diameter (equivalent diameter) and the length l of the hole 15b.

  The solid-liquid mixed phase flow classified by the classification layer 15 enters the container 21 of the settling device 20 through the opening 31 provided on the side walls of the containers 11 and 21, and as shown in FIGS. The gap 22b between the inclined plate 23a and the inclined plate 23a on one side is supplied from the direction orthogonal to the inclined direction of the inclined plate 23a, that is, from the horizontal direction. Thus, by supplying the solid-liquid mixed phase flow to the side surface of the laminated inclined plate 23 from the direction orthogonal to the inclined direction of the inclined plate 23a, the laminated inclined plate 23 does not impede the flow, and the average flow velocity is also reduced. Thus, the solid-liquid mixed phase flow supplied to the gap 23a between the inclined plate 23a and the inclined plate 23a of the laminated inclined plate 23 flows downward along the inclined plate 23a, and particles in the solid-liquid mixed phase flow are inclined in the process. It settles and accumulates on the plate 23a, and finally falls from the lower part of the laminated inclined plate 23. The solid-liquid mixed phase flow exiting from the lower part of the laminated inclined plate 23 enters the gap 22b between the inclined plate 22a and the inclined plate 22a of the lower laminated inclined plate 22 and flows downward along the inclined plate 22a. In the process, particles in the solid-liquid mixed phase flow settle and deposit on the inclined plate 22 a and finally fall from the lower portion of the laminated inclined plate 22. As a result, particles settle and deposit at the bottom of the settling device 20. The deposit thus formed is taken out from the bottom of the container 21 as necessary. On the other hand, the solid-liquid mixed phase flow that has passed through the laminated inclined plates 23, 22 rises through the gap between the laminated inclined plates 22, 23 and the container 21, and the discharge port 32 provided on the side wall of the container 21. Overflow from the outside. The handling of the solid-liquid mixed phase flow that has overflowed out of the container 21 in this way is determined as necessary. For example, the solid-liquid mixed phase flow is returned to the stirring layer 12 via a pipe and used as a cleaning liquid.

[Specific configuration example of cleaning and classification system]
Next, a specific configuration example of this cleaning and classification system will be described.

  FIG. 14 shows a first configuration example. As shown in FIG. 14, in the first configuration example, the bottom of the container 11 has a quadrangular pyramid shape that is tapered downward, and the stirring layer 12 is provided therein. Connected to the side wall of the stirring layer 12 is an introduction pipe 41 for introducing the cleaning material into the stirring layer 12. An inlet 42 is provided at the upper end of the introduction pipe 41 for introducing the cleaning material. An introduction pipe 43 for introducing the cleaning liquid into the stirring layer 12 is also connected to the side wall of the stirring layer 12. In addition, a stirring pump 44 is installed inside the stirring layer 12, and the mixed particles and the cleaning liquid supplied into the stirring layer 12 can be stirred and mixed by the stirring pump 44. The introduction pipe 43 is connected to the bottom of a rectangular parallelepiped liquid receiving tank 46 through a high-pressure pump 45. The liquid receiving tank 46 is attached to the lower front portion of the discharge port 32 at the upper side of the side wall of the container 21 so as to be able to receive the solid-liquid mixed phase flow that has overflowed beyond the discharge port 32.

  In the container 21 of the settling device 20, two-stage laminated inclined plates 22 and 23 are provided. The laminated inclined plate 22 is composed of a plurality of inclined plates 22a laminated at intervals. Similarly, the laminated inclined plate 23 is composed of a plurality of inclined plates 23a laminated at intervals. If necessary, the bottom of the container 21 is provided with a take-out port for taking out deposits made of settled particles. Further, for example, a metal net and a filter cloth (filter) under the container 21 may be provided at the bottom of the container 21 to provide a space where deposits do not enter, and moisture may be removed from the swollen soil by suction (suction).

  As an example, the operation of the cleaning and classification system according to the first configuration example will be described in the case where the mixed particles having a particle size distribution are soil (earth and sand, fine sand) and the cleaning liquid is water.

  First, the soil to be washed and classified is put into the inlet 42 in a state where the stirring submersible pump as the stirring pump 44 and the high-pressure pump 45 are operated. The introduced soil is introduced into the stirring layer 12 through the introduction pipe 41. The soil thus introduced into the agitation layer 12 is agitated and mixed by the high-speed pump water flow introduced into the agitation layer 12 from the introduction pipe 43 by the high-pressure pump 45 and further agitated and mixed by the agitation pump 44. Thus, a non-uniform solid-liquid mixed phase flow (muddy water) made of soil and water is generated in the stirring layer 12. This solid-liquid mixed phase flow is carried upstream by a high-speed jet water flow. First, by passing through the rectifying layer 13 made of a wave-like static mixer, the non-uniform solid-liquid mixed phase flow is converted into a uniform flow. Next, the uniform flow of this solid-liquid mixed phase flow is made into a laminar flow in the process of passing through the laminar flow layer 14, and particles having a large sedimentation velocity are removed. The solid-liquid mixed phase flow converted into the laminar flow in the laminar flow layer 14 enters the classification layer 15, and in the process of passing through the classification layer 15, silt having a particle size of several tens of μm or more is classified. The deposit formed on the bottom of the stirring layer 12 is taken out from the earth and sand take-out port as necessary.

  Mainly silt or silt and clay in the solid-liquid mixed phase flow that has passed through the classification device 10 enters the gap between the inclined plate 23a and the inclined plate 23a on the side surface of the upper layered inclined plate 23 of the settling device 20, and the inclined plate. 23a, and further enters the gap between the inclined plate 22a and the inclined plate 22a of the lower layered inclined plate 22, settles along the inclined plate 22a, and finally settles to the bottom of the container 21, accumulate. The solid-liquid mixed phase flow that has overflowed from the discharge port 32 of the container 21 of the settling device 20 enters the liquid receiving tank 46 and is returned to the stirring layer 12 from the introduction pipe 43 by the high-pressure pump 45. The clay in the solid-liquid mixed phase flow that has passed through the classifier 10 hardly sinks by the laminated inclined plates 22 and 23, and therefore does not settle at the bottom of the container 21. In this case, although the final wastewater from the settling device 20 contains clay, the weight fraction of clay is a value that can be ignored as compared with the raw soil. 12 can be restored.

  FIG. 14 schematically shows the flow of the solid-liquid mixed phase flow (muddy water) with thin broken arrows and the flow of sand, silt, and clay with thick broken arrows.

  FIG. 15 shows a second configuration example. As shown in FIG. 15, in the second configuration example, the bottom portion of the container 11 has a quadrangular pyramid shape that is tapered downward, and the stirring layer 12 is provided therein. The introduction pipe 41 is connected to the introduction pipe 43 from above. In this case, the stirring pump 44 is not installed in the stirring layer 12. Other configurations of the second configuration example are the same as those of the first configuration example.

  As an example, the operation of the cleaning and classification system according to the second configuration example will be described in the case where the mixed particles having a particle size distribution are soil and the cleaning liquid is water.

  First, the soil to be washed and classified is put into the inlet 42 with the high-pressure pump 45 in operation. As shown in FIG. 16, the introduced soil reaches the junction of the introduction pipe 41 and the introduction pipe 43 through the introduction pipe 41 and is sucked into the introduction pipe 43 by the high-speed jet water flow supplied from the introduction pipe 43. It is. In this way, soil and water are introduced into the stirring layer 12 and mixed by stirring with a high-speed jet water stream. Thus, a solid-liquid mixed phase flow (muddy water) composed of soil and water is generated in the stirring layer 12. The subsequent operation is the same as in the first configuration example.

  FIG. 15 schematically shows the flow of the solid-liquid mixed phase flow (muddy water) with thin broken arrows and the flow of sand, silt and clay with thick broken arrows.

  FIG. 17 shows a third configuration example. As shown in FIG. 17, in the third configuration example, the bottom of the container 11 has a quadrangular pyramid shape that is tapered downward, and the stirring layer 12 is provided therein. Similarly to the second configuration example, the introduction pipe 41 is connected to the introduction pipe 43 from above, and the stirring pump 44 is not installed in the stirring layer 12. Connected to the bottom of the stirring layer 12 is a discharge pipe 47 for taking out the sediment that has settled on the bottom of the stirring layer 12 to the outside. A sand pump 48 is connected in the middle of the discharge pipe 47, and the earth and sand collected from the discharge pipe 47 is transferred upward by the sand pump 48 and is collected from the collection port 49 to the washing earth and sand collection device 50. Yes. An inlet pipe 51 is connected to the side wall of the recovery port 49, and muddy water is supplied from the inlet pipe 51 to the inlet 42. Other configurations of the third configuration example are the same as those of the first configuration example.

  On the other hand, the bottom of the container 21 of the settling device 20 has a quadrangular pyramid shape that is tapered downward, and the lower end of the container 21 takes out the deposit deposited on the bottom of the settling device 20 to the outside. 52 is provided.

  As an example, the operation of the cleaning and classification system according to this third configuration example will be described in the case where the mixed particles having a particle size distribution are soil and the cleaning liquid is water.

  First, the soil to be washed and classified is introduced into the inlet 42 with the high-pressure pump 45 and the sand pump 48 in operation. The introduced soil reaches the joining portion of the introduction pipe 41 and the introduction pipe 43 through the introduction pipe 41 and is sucked into the introduction pipe 43 by the high-speed jet water flow supplied from the introduction pipe 43. In this way, the soil and water are introduced into the stirring layer 12, and are stirred and mixed by the high-speed jet water flow to generate a solid-liquid mixed phase flow (muddy water) composed of soil and water. The subsequent operation is the same as in the first configuration example. On the other hand, earth and sand containing water is taken out from the bottom of the stirring layer 12 into the introduction pipe 47 and returned to the recovery port 49 by the sand pump 48. Sediment components are collected in the washing earth and sand collecting device 50 from the earth and sand containing the water returned to the collection port 49, and muddy water is introduced into the loading port 42.

  On the other hand, in the sedimentation device 20, the deposit accumulated at the bottom of the container 21 is taken out from the take-out port 52 and then made into a dehydrated cake with a filter press or the like, and the volume is reduced.

  FIG. 17 schematically shows the flow of solid-liquid mixed phase flow (muddy water) with thin broken arrows and the flow of sand, silt and clay with thick broken arrows.

[Verification experiment of function of each layer constituting classifier 10]
An experiment was conducted to verify the function of each layer constituting the classifier 10. For this purpose, a classification device as shown in FIG. 18 was produced. As the rectifying layer 13, a square polycarbonate corrugated plate having a side of 20 cm (total thickness is 9 mm, wave pitch is 32 mm, and plate thickness is 0.7 mm) is 44 cm high and 20 cm high. A rectangular parallelepiped having a size of 40 cm and a depth of 40 cm was used by stacking two steps so as to have a total thickness of 40 cm. As shown in FIG. 4D, the laminar flow layer 14 has a rectangular parallelepiped shape having a height of 5 cm, a width of 40 cm, and a depth of 40 cm in which cylindrical holes 14b having a hexagonal cross section of 1 cm in diameter are arranged in a honeycomb shape. A structure was used. As shown in FIG. 5D, the classification layer 15 is a rectangular parallelepiped structure having a height of 10 cm, a width of 40 cm, and a depth of 40 cm in which cylindrical holes 15b having a hexagonal cross section of 3 mm in diameter are arranged in a honeycomb shape. The body was tilted about 27 degrees from the horizontal direction. In this case, the inclination angle Ψ of the hole 15b with respect to the horizontal direction is about 63 degrees. Although not shown in FIG. 18, a stirring layer 12 including an underwater pump for stirring is provided under the rectifying layer, and soil and water are supplied to the stirring layer 12 from the outside. . The flow rate Q was 50 L / min. Since the purpose of this experiment was to classify fine sand without using a sieve, the settled fine sand generated during soil washing was used as raw sand. D ₅₀ (particle size when the ratio is 50% in the particle size distribution of the raw sand) = 132 μm, and the raw sand contains about 16% of fine particles having a particle size of 51 μm or less.

  As shown in FIG. 18, a strong turbulent state is present in the stirring layer below the rectifying layer. The rectifying layer is designed so that the large-scale vortex generated in the stirring layer is divided so that the average flow becomes uniform vertically upward. Furthermore, in a laminar layer, silt and sand dispersed by turbulent diffusion settle or rise due to the action of gravity and fluid drag. It is considered that the maximum diameter of the soil particles passing through the laminar bed is almost independent of the diameter of the cylindrical hole (pipe) and depends only on the flow rate. Finally, the soil particles that could not pass through the cylindrical hole (pipe) of the classification layer settle as a plume from the lower part of the classification layer. In addition, the inclination angle Ψ of the cylindrical hole (pipe) of the classification layer in this experiment is about 63 degrees as described above, and the maximum particle size of particles passing through the cylindrical hole (pipe) is expressed by the formula ( According to 3), it is 20 μm.

  FIG. 19 is a photograph of a sample taken with a camera, taken from a valve in which the fluid after passing through each layer during classification is attached to the side wall of the container. Comparing the sample after passing through the laminar flow layer with the sample after passing through the classification layer, the turbidity of the solid-liquid mixed phase flow (muddy water) clearly shows a difference. The turbidity of the sample after passing is greatly reduced. After passing through the classification layer, the turbidity of the sample after passing through a filter cloth (filter membrane) having a pore diameter of 1 to 2 μm is further lowered.

  FIG. 20 is a photograph of the lower part of the classification layer. As shown in FIG. 20, soil particles that cannot pass through the inclined cylindrical hole (pipe) of the classification layer are discharged along the bottom surface of the cylindrical hole, and as a fine sand plume along the bottom of the classification layer A fall was observed.

[Soil washing experiment with washing and classification system]
Next, the results of soil washing experiments using this washing and classification system will be described.

  In order to verify the effect of each layer in the classification device 10 and the settling device 20 of the cleaning and classification system, the soil cleaning and classification system (cleaning and classification system according to Example 1) shown in FIG. The experiment was conducted. The experimental flow rate Q = 91 L / min, the total amount of water in the tanks of the classifier 10 and the settling device 20 is 315 L, and turbid water circulates once in approximately 3 to 4 minutes. A sample was collected at each measurement point in FIG. 21, and suspended solid (SS) was measured. Station 1 is in the stirring layer and the amount of SS is maximized. Station 2 is immediately after passing through the laminar flow layer, station 3 is immediately after passing through the classification layer, and station 4 is the discharge port, and the water that has passed there returns to the agitation tank (station 1) again. The measuring point 5 is immediately after passing through the upper laminated inclined plate constituting the settling layer of the settling device 20, and the measuring point 6 is the bottom of the settling device 20.

  FIG. 22A shows a measurement result of the SS amount in the soil washing and classification system having the configuration shown in FIG. 21 in which the settling device is installed. From FIG. 22A, it can be seen that after passing through the classification layer (station 3), the SS amount is significantly reduced, and further decreased in the sedimentation layer (station 4). At station 6, the amount of SS is increased due to the precipitated particles. On the other hand, FIG. 22B shows the measurement result of the SS amount when no settling device is installed in the soil washing and classification system having the configuration shown in FIG. Comparing FIG. 22B with FIG. 22A, when there is no settling device, it is considered that the amount of SS is small even after the lapse of time, and therefore, muddy water is circulating in the soil washing and classification system without settling.

  FIG. 23 shows the particle size distribution before and after passing through the laminar laminar (stations 1 and 2), and the area under the curve in the figure represents the SS amount. Most of the particles in the solid-liquid mixed phase flow after passing through the laminar flow layer are particles having a particle size of 100 μm or less. Theoretically, when the flow rate is 91 L / min, it is in agreement with the fact that particles having a particle size of about 140 μm or more cannot pass through in a laminar flow layer (pore size 3/16 inch). Moreover, it turns out that the SS amount of laminar bed downstream is falling by installing a sedimentation apparatus.

  FIG. 24 shows the particle size distribution (probability distribution function (the probability distribution function)) of the sedimentation device and the sedimentation device after the agitation submersible pump provided in the agitation layer is operated for 30 minutes and the soil is agitated, classified and settled. probability distribution function)). A particle size distribution of 51 μm or less could not be measured due to the measurement with a sieve. In the classification layer (pore size 1/8 inch), particles having a particle size of 25 μm or more cannot theoretically pass, but particles having a particle size of about 50 μm also pass. Possible causes are that the particle cross-sectional area is reduced by the particles settled at the bottom of the inclined cylindrical hole (pipe) in the classification layer, the flow velocity is increased, and the concentration of solid components in the solid-liquid mixed phase flow is increased. A decrease in sedimentation velocity, turbulent diffusion, etc. can be considered.

  This soil washing and classification system can control the classification threshold, and can classify particles that are approximately one-hundred or more of the pore diameter of the cylindrical hole (pipe) of the classification layer. In addition, since the inclined cylindrical hole (pipe) used in this experiment is about L / h = 50 and the threshold for classification is as large as several tens of μm, the silt also has the inclined cylindrical hole (pipe). ) Passed. However, in the present settling device, there was a large space without inclined plates at both ends for the convenience of preparation, but there was an effect that the amount of SS in the settling device was halved. Since it is important to make the flow velocity of the flow toward the discharge port as uniform as possible and to reduce the flow velocity, the inclined plate is arranged in parallel toward the discharge port.

  For example, if the decontamination effect is improved by separating only the clay component from the soil by classification, the classification threshold needs to be about 5 μm, which is the re-small diameter of silt. In this case, when the inclination angle Ψ of the cylindrical hole (pipe) in the classification layer is 40 degrees, the length of the hole of the cylindrical hole (pipe) is 400 times longer (FIG. 12). reference).

[Cleaning experiment of radioactively contaminated soil by cleaning and classification system]
Next, the results of cleaning (decontamination) and classification of radioactively contaminated soil using the soil cleaning and classification system shown in FIG. 21 will be described. Since the purpose of this experiment was to classify fine sand without using a sieve, the settled fine sand generated during soil washing was used as raw sand. The particle size distribution of the raw sand is shown in FIG. As shown in FIG. 25, the raw sand contains about 38% of fine particles having a particle size of 51 μm or less. The radioactivity of the radioactive material contained in the raw sand is as shown in Table 1.

  It is known that the cesium ions taken into the clay can be desorbed from the clay by destroying the layer structure of the clay contained in the radioactively contaminated soil with an acid. As the acid, oxalic acid used in pipe cleaning of nuclear power plants is used. Oxalic acid produces an oxide film on the surface of stainless steel, has a function of preventing the corrosion of stainless steel, and does not corrode the pump, and it is cited as an advantage that post-treatment is easy. Therefore, oxalic acid was used for decontamination.

The experimental procedure is as follows.
(1) Put 1.5 kg of raw sand into the stirring layer of the classifier, and circulate the solid-liquid mixed phase flow of the classifier through the settling device for 15 minutes to classify clay and silt.
(2) Oxalic acid hydrate 1.5 kg (0.08 mol / L acid) is put into the stirring layer of the classifier, and a solid-liquid mixed phase flow is circulated for 20 minutes only with the classifier to perform washing.
(3) The solid-liquid mixed phase flow of the classifier is circulated for 10 minutes through the settling device to classify clay and silt. At this time, a solid-liquid mixed phase flow after passing through each layer is collected.
(4) Stop the submersible pump for stirring of the stirring layer of the classifier, collect the fine-grained soil that has settled at the bottom of the stirring layer, and measure the particle size distribution and radiation dose.

  The experimental results are as follows. FIG. 26 is a photograph of a sample taken with a camera, taken from a valve in which the fluid after passing through each layer is attached to the side wall of the container. When the sample after passing through the laminar flow layer and the sample after passing through the classification layer are compared, a clear difference in turbidity appears. Here, the sample after passing through the filter cloth is a sample that has passed through a filter cloth having a pore diameter of 1 to 2 μm.

  The particle size distribution and the radiation dose were measured for the fine-grained soil after the oxalic acid washing and classification in the experimental procedure (4). The particle size distribution is shown in FIG. As shown in FIG. 25, those having a particle size of 51 μm or less are reduced and the proportion of particles having a particle size of 51 to 106 μm is increased as compared with raw sand. Table 1 shows measured values of radiation dose of raw sand and oxalic acid washed sand. The reduction in radiation density (Bq / kg) after cleaning cannot be distinguished in this experiment due to the decrease in the soil particle component having a large surface area of 51 μm or less and the detachment of cesium from the soil particles by oxalic acid. . In order to clarify these, it is necessary to further verify the precise measurement of the particle size distribution and the effect of oxalic acid.

  As described above, the cleaning effect of oxalic acid on soil contaminated with radioactive rays and the classification effect of inclined pipes were experimentally investigated. In the washing with oxalic acid, it has been found that a high concentration of acid (1 mol / L or more) must be used in order to make the decontamination rate at least 50% or more. In addition, the classification device can control the classification threshold value, and can classify particles having a particle size of approximately one-hundred or more of the pore diameter of the inclined pipe line. However, since the gradient pipe of the classification layer used in this experiment is about L / h = 50 and the threshold for classification is as large as several tens of μm, silt other than the clay particles also passed through the classification layer.

  For example, if the decontamination efficiency is increased by separating only clay components from radioactively contaminated soil by classification, the classification threshold needs to be about 5 μm, which is the minimum silt diameter. As already described, in this case, when the inclination angle Ψ of the inclined pipe is 40 degrees, the length of the inclined pipe is required to be 400 times the hole diameter (see FIG. 12).

  Now, it is necessary to reduce the volume by removing the water after removing the clay-only muddy water by the above-described wet classification. Usually, a flocculant is added to the muddy water to generate a floc containing clay particles, thereby increasing the sedimentation rate and collecting the precipitate. Further, the precipitate (swelled) is collected by a centrifugal dehydrator such as a decanter or a filter press. Dehydrated from clay. However, flocs contain a large amount of moisture and the apparent specific gravity is close to 1, so that the sedimentation speed is relatively small and the floc strength is small, so that they are broken and dispersed by slight turbulence. The purpose of muddy water treatment in the case of decontamination is not to clean the water but to take out the clay. Therefore, it is desired to develop an apparatus that agglomerates clay particles in high-concentration mud water to a size of several tens of μm and efficiently recovers them.

  As described above, according to the first embodiment, mixing (dispersing) and classification of mixed particles having a particle size distribution, for example, soil, can be performed in the container 11 of the classification device 10, whereby the classification device 10. In addition, since the cleaning and classification system can be constructed by the settling device 20, the size of the cleaning and classification system can be reduced. In addition, this cleaning and classification system can continuously adjust the classification threshold by adjusting the height and length of the inclined pipelines of the classification layer 15 of the classification device 10. Furthermore, when this washing and classification system is used for soil washing and classification, when the final wastewater is discharged into the environment, it is necessary to reduce the amount of SS separately using a coagulant or the like. Since the amount of silt and clay contained in can be significantly reduced, the amount of the flocculant used and the processing time can be greatly reduced.

<Second Embodiment>
[Cleaning and classification system]
FIG. 27 shows a cleaning and classification system according to the second embodiment. As shown in FIG. 27, in this cleaning and classification system, a rectifying layer 61 composed of a wave-like static mixer is provided between the classification device 10 and the settling device 20. More specifically, the rectifying layer 61 is provided in the opening 31 provided on the side wall of the container 11 of the classifying device 10 and the container 21 of the settling device 20. In this case, the solid-liquid mixed phase flow after classification by the classifying device 10 enters the rectifying layer 61 from the horizontal direction, is rectified to become a uniform flow, and is then supplied to the side surface of the laminated inclined plate 23 of the settling device 20.

  The rest of the cleaning and classification system is the same as that of the first embodiment. The operation of this cleaning and classification system is supplied to the side surface of the laminated inclined plate 23 of the settling device 20 after the solid-liquid mixed phase flow after classification by the classification device 10 is rectified by the rectification layer 61 to become a uniform flow. Except for this, it is the same as the first embodiment.

  According to the second embodiment, in addition to the same advantages as those of the first embodiment, the solid-liquid mixed phase flow rectified by the rectifying layer 61 and converted into a uniform flow is subjected to the laminated inclined plate of the settling device 20. Since it can supply to the side surface of 23, the advantage that the sedimentation of the particle | grains by the lamination | stacking inclination board 23 can be performed more efficiently can be acquired.

<Third Embodiment>
[Cleaning and classification system]
FIG. 28 shows a cleaning and classification system according to the third embodiment. As shown in FIG. 28, in this cleaning and classification system, when the cleaning and classification system according to the first embodiment is used for soil cleaning and classification, clay and silt after classification by the classification device 10 are removed. The solid-liquid mixed phase flow is supplied to a sedimentation device 20 (not shown in FIG. 28), and coagulated and settled, water is reused, and the settled soil is returned to the stirring layer 12 of the classifier 10. Then, the earth and sand components (sand and fine particles) accumulated at the bottom of the stirring layer 12 of the classifier 10 are taken out, and the classifier 65 connected in series with the classifier 10 has the same configuration as the classifier 10. It supplies to a layer and performs chemical cleaning and classification in a classifier 65. The solid-liquid mixed phase flow (including low-concentration silt and chemical) subjected to chemical cleaning and classification in this manner is taken out from the classification device 65 and filtered through a filter membrane. The filtered silt is left on the filter membrane, and the chemical that has permeated the filter membrane can be reused.

  According to the third embodiment, in addition to the same advantages as the first embodiment, it is possible to obtain the advantage that the water, chemicals and soil used for cleaning can be effectively used.

<Fourth embodiment>
[Cleaning and classification system]
FIG. 29 shows a cleaning and classification system according to the fourth embodiment. As shown in FIG. 29, in this cleaning and classification system, an aggregation promoting layer 71 is provided between the classification device 10 and the sedimentation device 20. More specifically, the container 11 of the classification device 10 and the container 21 of the settling device 20 are connected via an aggregation promoting layer 71 provided in the opening 31. The aggregation promoting layer 71 is formed by the laminated inclined plates 22 and 23 of the settling device 20 by increasing the particle size by precipitating and depositing particles as much as possible from the solid-liquid mixed phase flow after classification by the classification layer 15 of the classifying device 10. This is to improve the efficiency of sedimentation of particles. The size of the aggregation promoting layer 71 is not particularly limited and may be selected as necessary. For example, the length of the aggregation promoting layer 71 in the direction of the central axis is 10 to 20 cm, the width is 20 to 40 cm, and the height is 20 ~ 30 cm.

  FIG. 30 shows a specific configuration example of the aggregation promoting layer 71. As shown in FIG. 30, in this example, the aggregation promoting layer 71 has a plurality of partition walls 71a parallel to the horizontal plane and stacked in the vertical direction at intervals, and a cross section between the partition walls 71a and 71a. A long and narrow rectangular hole 71b (pipe) is formed. It is preferable that the thickness of the partition wall 71a be sufficiently smaller than the distance between the partition wall 71a and the partition wall 71a, in other words, the height of each pipeline. In the aggregation promoting layer 71, the sedimentation distance of the particles is reduced by utilizing the height of the pipe line between the partition walls 71a. That is, as shown in FIG. 30, the particles in the solid-liquid mixed phase flow coming from the classifier 10 settle on the partition wall 71a at the bottom of the pipe after being moved by a certain distance, and are aggregated by being deposited. The particles aggregated on the partition wall 71 a at the bottom of the pipe line are flushed to the settling device 20 by the shearing force of the flow and enter the side surface of the laminated inclined plate 23. Further, when the pipe is blocked by particles deposited and deposited on the partition wall 71a at the bottom of the pipeline, the flow velocity increases, so that the particles deposited and deposited on the partition wall 71a are easily flushed.

  FIG. 31 shows another configuration example of the aggregation promoting layer 71. As shown in FIG. 31, in this example, the aggregation promoting layer 71 is inclined at an angle Ω with respect to the horizontal direction so that the settling device 20 side is lower than the classification device 10 side. Ω is, for example, 0 degree <Ω ≦ 10 degrees, preferably 0 degree <Ω ≦ 5 degrees. In this example, since the aggregation promoting layer 71 is inclined at an angle Ω with respect to the horizontal direction so that the settling device 20 side is lower than the classification device 10 side, it settles on the partition wall 71a at the bottom of the pipeline, Aggregated particles can be easily discharged out of the aggregation promoting layer 71.

  32A to 32D show still another configuration example of the aggregation promoting layer 71. 32A is a plan view, FIG. 32B is a vertical cross-sectional view including the central axis of the aggregation promoting layer 71, and FIG. 32C is a direction parallel to the partition wall 71a in the portion between the vertical plate 71c and the vertical plate 71c in FIG. FIG. 32D is an enlarged cross-sectional view showing a state where particles are captured in a region (region surrounded by an alternate long and short dash line) between the vertical plate 71c and the vertical plate 71c in FIG. 32B. As shown in FIGS. 32A to 32D, the aggregation promoting layer 71 has a plurality of partition walls 71a parallel to the horizontal plane and stacked in the vertical direction with a space therebetween, and a cross-sectional shape between the partition walls 71a and 71a. A long and narrow rectangular hole 71b (pipe) is formed. The thickness of the partition wall 71a is preferably sufficiently smaller than the distance between the partition wall 71a and the partition wall 71a, in other words, the height of each flow path. In the partition wall 71 a at the bottom of each pipe line, a vertical plate 71 c extending in the direction connecting the classification device 10 and the sedimentation device 20, in other words, in the direction orthogonal to the central axis of the aggregation promoting layer 71 is the center of the aggregation promoting layer 71. It is provided at equal intervals in the direction of the shaft. The height of the vertical plate 71c is smaller than the height of each pipeline so that the flow in each pipeline is not hindered, and the interval between the vertical plate 71c and the partition wall 71a at the ceiling of the pipeline is sufficiently large. To. In this case, as shown in FIG. 32D, in each pipe line, the flow velocity in the rectangular region between the vertical plates 71c and 71c is very small, so the particles trapped in this rectangular region Is easily sedimented. Further, as shown in FIG. 32C, the partition wall 71a has a gable roof shape, and has a mountain shape in which two inclined surfaces face down the book from the top in the direction orthogonal to the pipe line to both sides. Therefore, the particles captured in the rectangular region between the vertical plate 71c and the vertical plate 71c are easily discharged toward both sides. However, the partition wall 71a may be formed horizontally instead of the gable roof shape.

[Specific configuration example of cleaning and classification system]
Next, a specific configuration example of the cleaning and classification system will be described.
FIG. 33 shows a fourth configuration example. As shown in FIG. 33, in the fourth configuration example, an aggregation promoting layer 71 is provided between the classifying device 10 and the sedimentation device 20 in the first configuration example shown in FIG. Others are the same as in the first configuration example.

  As an example, the operation of the cleaning and classification system according to the fourth configuration example will be described in the case where the mixed particles having a particle size distribution are soil and the cleaning liquid is water.

  First, the soil to be washed and classified is put into the inlet 42 in a state where the stirring submersible pump as the stirring pump 44 and the high-pressure pump 45 are operated. The introduced soil is introduced into the stirring layer 12 through the introduction pipe 41. The soil thus introduced into the agitation layer 12 is agitated and mixed by the high-speed pump water flow introduced into the agitation layer 12 from the introduction pipe 43 by the high-pressure pump 45 and further agitated and mixed by the agitation pump 44. Thus, a solid-liquid mixed phase flow (muddy water) composed of soil and water is generated in the stirring layer 12. This solid-liquid mixed phase flow is carried upstream by a high-speed jet water flow. First, the solid-liquid mixed phase flow is converted into a uniform flow by passing through the rectifying layer 13 made of a wave-like static mixer. Next, the uniform flow of the solid-liquid mixed phase flow is converted into a laminar flow in the process of passing through the laminar flow layer 14, and particles having a large sedimentation velocity are classified. The solid-liquid mixed phase flow converted into the laminar flow in the laminar flow layer 14 enters the classification layer 15, and in the process of passing through the classification layer 15, silt having a particle size of several tens of μm or more is classified.

  Soil components (silt and clay) that have passed through the classification device 10 enter the aggregation promoting layer 71, and the silt is aggregated as much as possible, is flushed by the shear flow, and enters the sedimentation device 20. Thus, the solid-liquid mixed phase flow that has entered the settling device 20 enters the gap between the inclined plate 23a and the inclined plate 23a on the side surface of the upper layered inclined plate 23 of the settling device 20, settles along the inclined plate 23a, and further It enters into the gap between the inclined plate 22 a and the inclined plate 22 a of the lower layered inclined plate 22, settles along the inclined plate 22 a, and finally settles and accumulates at the bottom of the container 21. The solid-liquid mixed phase flow that has overflowed from the discharge port 32 of the container 21 of the classifier 10 enters the liquid receiving tank 46, is returned to the stirring layer 12 by the high-pressure pump 45 from the introduction pipe 43, and is used as washing water.

  FIG. 33 schematically shows the flow of the solid-liquid mixed phase flow (muddy water) with thin broken arrows and the flow of sand, silt, and clay with thick broken arrows.

  FIG. 34 shows a fifth configuration example. As shown in FIG. 34, in the fifth configuration example, an aggregation promoting layer 71 is provided between the classifying device 10 and the settling device 20 in the second configuration example shown in FIG. Others are the same as in the second configuration example.

  As an example, the operation of the cleaning and classification system according to the fifth configuration example will be described in the case where the mixed particles having a particle size distribution are soil and the cleaning liquid is water.

  First, the soil to be washed and classified is put into the inlet 42 with the high-pressure pump 45 in operation. As shown in FIG. 34, the introduced soil reaches the junction of the introduction pipe 41 and the introduction pipe 43 through the introduction pipe 41 and is sucked into the introduction pipe 43 by the high-speed jet water flow supplied from the introduction pipe 43. It is. In this way, soil and water are introduced into the stirring layer 12 and mixed by stirring with a high-speed jet water stream. Thus, a solid-liquid mixed phase flow (muddy water) composed of soil and water is generated in the stirring layer 12. The subsequent operation is the same as in the fourth configuration example.

  FIG. 34 schematically shows the flow of the solid-liquid mixed phase flow (muddy water) with thin broken arrows and the flow of sand, silt, and clay with thick broken arrows.

  FIG. 35 shows a sixth configuration example. As shown in FIG. 35, in the sixth configuration example, an aggregation promoting layer 71 is provided between the classifying device 10 and the settling device 20 in the third configuration example shown in FIG. Others are the same as in the third configuration example.

  As an example, the operation of the cleaning and classification system according to the sixth configuration example will be described in the case where the mixed particles having a particle size distribution are soil and the cleaning liquid is water.

  First, the soil to be washed and classified is introduced into the inlet 42 with the high-pressure pump 45 and the sand pump 48 in operation. The introduced soil reaches the joining portion of the introduction pipe 41 and the introduction pipe 43 through the introduction pipe 41 and is sucked into the introduction pipe 43 by the high-speed jet water flow supplied from the introduction pipe 43. In this way, soil and water are introduced into the stirring layer 12 and mixed by stirring with a high-speed jet water stream. Thus, a solid-liquid mixed phase flow (muddy water) composed of soil and water is generated in the stirring layer 12. The subsequent operation is the same as in the fourth configuration example. On the other hand, earth and sand containing water is taken out from the bottom of the stirring layer 12 into the introduction pipe 47 and returned to the recovery port 49 by the sand pump 48. Sediment components are collected in the washing earth and sand collecting device 50 from the earth and sand containing the water returned to the collection port 49, and muddy water is introduced into the loading port 42.

  On the other hand, in the sedimentation device 20, the deposit accumulated at the bottom of the container 21 is taken out from the take-out port 52 and then made into a dehydrated cake with a filter press or the like, and the volume is reduced.

  FIG. 35 schematically shows the flow of the solid-liquid mixed phase flow (muddy water) with thin broken arrows and the flow of sand, silt and clay with thick broken arrows.

  An example of this cleaning and classification system will be described. FIG. 36 shows a cleaning and classification system according to Example 2. As shown in FIG. 36, in this cleaning and classification system, the bottom of the container 11 has a quadrangular pyramid shape that is tapered downward, and the stirring layer 12 is provided therein. An introduction pipe 43 for introducing the cleaning liquid into the stirring layer 12 is connected to the side wall of the stirring layer 12. The introduction pipe 43 is connected to the bottom of a rectangular parallelepiped liquid receiving tank 46 through a high-pressure pump 45. The liquid receiving tank 46 is attached to the lower front portion of the discharge port 32 at the upper side of the side wall of the container 21 so as to be able to receive the solid-liquid mixed phase flow that has overflowed beyond the discharge port 32.

  In the container 21 of the settling device 20, two-stage laminated inclined plates 22 and 23 are provided. The laminated inclined plate 22 is composed of a plurality of inclined plates 22a laminated at intervals. Similarly, the laminated inclined plate 23 is composed of a plurality of inclined plates 23a laminated at intervals.

  An aggregation promoting layer 71 is provided between the classification device 10 and the sedimentation device 20.

  As the aggregation promoting layer 71, the one shown in FIG. 37 or FIG. 38 was used. The aggregation promoting layer 71 shown in FIG. 37 is the same as that shown in FIGS. 32A to 32D except that the partition wall 71a is not a gable roof shape but is horizontal. As shown in FIG. 37, the total length of the aggregation promoting layer 71 is 150 mm, the distance between the partition walls 71a and the partition walls 71a (the height of the pipeline) is 24 mm, and the distance between the vertical plates 71c is 10 mm. Further, the aggregation promoting layer 71 shown in FIG. 38 is the same as that shown in FIG. As shown in FIG. 38, the total length of the aggregation promoting layer 71 is 100 mm, and the distance between the partition walls 71a and the partition walls 71a (the height of the pipeline) is 5 mm.

  While circulating water throughout the classifier 10 and the settling device 20, 100 g of kaolin is introduced into the liquid receiving tank 46, and 7 minutes at the inlet (station 1) and outlet (station 2) of the aggregation promoting layer 71. The integrated concentration (SS) of was measured. FIG. 39 shows the measurement results. As shown in FIG. 39, both have a sedimentation effect of kaolin, and the sedimentation effect decreases as the flow velocity (u) of the flow entering the inlet of the aggregation promoting layer 71 (see FIG. 37 and FIG. 38) increases. It was found that there was no significant difference in the SS amount between the station 1 and the station 2.

  According to the fourth embodiment, in addition to the same advantages as those of the first embodiment, the aggregation promoting layer 71 is provided between the classifying device 10 and the settling device 20, whereby the classifying device. The particles having a small particle size included in the solid-liquid mixed phase flow from 10 can be aggregated as much as possible by the aggregation promoting layer 71 to increase the particle size, and thereby, by the laminated inclined plates 22 and 23 of the settling device 20. The advantage that the particles can be efficiently settled can be obtained.

<Fifth embodiment>
[Cleaning and classification system]
FIG. 40 shows a cleaning and classification system according to the fifth embodiment. As shown in FIG. 40, in this cleaning and classification system, a rectifying layer 61 and a coagulation accelerating layer comprising a wave-like static mixer are disposed between the classification device 10 and the sedimentation device 20 in this order from the classification device 10 toward the sedimentation device 20. 71 is provided. Others are the same as in the first embodiment.

  According to the fifth embodiment, the same advantages as those of the second and fourth embodiments can be obtained.

  Although the embodiments and examples of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments and examples, and various modifications based on the technical idea of the present invention. Is possible.

  For example, the numerical values, shapes, structures, arrangements, and the like given in the above embodiments and examples are merely examples, and different numerical values, shapes, structures, arrangements, and the like may be used as necessary.

  DESCRIPTION OF SYMBOLS 10, 65 ... Classification apparatus, 11 ... Container, 12 ... Stirring layer, 13, 61 ... Rectification layer, 13a, 13b, 13c ... Corrugated sheet laminated body, 14 ... Laminar flow layer, 14a ... Septum, 14b ... Hole, 15 ... Classification layer, 15a ... partition wall, 15b ... hole, 16 ... corrugated plate, 20 ... sedimentation device, 21 ... container, 22, 23 ... laminated inclined plate, 22a, 23a ... inclined plate, 22b, 23b ... gap, 31 ... opening , 32 ... discharge port, 41, 43, 47, 51 ... introduction pipe, 44 ... stirring pump, 45 ... high pressure pump, 46 ... liquid receiving tank, 48 ... sand pump, 49 ... recovery port, 50 ... washing soil collection device 71 ... Aggregation promoting layer, 71a ... partition wall, 71b ... gap, 71c ... vertical plate

Claims (13)

Having a classifier and a settling device arranged in parallel with each other;
The classification device is
A first container;
The mixed particles having a particle size distribution and the cleaning liquid provided in the first container are supplied, and the mixed particles and the cleaning liquid are stirred to generate a solid-liquid mixed phase flow in which the mixed particles and the cleaning liquid are mixed. A stirring layer for,
A rectifying layer comprising a wavy static mixer for providing a uniform flow of the solid-liquid mixed phase flow supplied from the stirring layer, provided in the upper stage of the stirring layer,
A laminar flow layer provided in the upper stage of the rectifying layer for laminating the solid-liquid mixed phase flow that has passed through the rectifying layer;
Provided in the upper part of the laminar flow layer, the solid-liquid mixed phase stream passing through the laminar flow layer is supplied, for classifying the mixed particles, angle [psi (0 degrees to the horizontal <[psi <90 And a classification layer having a plurality of inclined pipelines,
The settling device
A second container;
An angle Θ (0 ° <Θ <90 °) with respect to the horizontal direction for settling and agglomerating particles in the solid-liquid mixed phase flow passing through the classification layer provided in the second container A cleaning and classification system having a laminated inclined plate in which a plurality of inclined plates are laminated with a space between each other, and the solid-liquid mixed phase flow is provided with a sedimentation layer supplied to a side surface of the laminated inclined plate.   The classification layer includes a structure having a plurality of cylindrical holes inclined at an angle Ψ with respect to the horizontal direction, or a laminated inclined board in which a plurality of plates inclined at an angle Ψ with respect to the horizontal direction are laminated at intervals. The cleaning and classification system according to claim 1. The cleaning and classification system according to claim 1 or 2, wherein the laminar flow layer is formed of a structure having a plurality of vertical cylindrical holes. Having a classifier and a settling device arranged in parallel with each other;
The classification device is
A first container;
The mixed particles having a particle size distribution and the cleaning liquid provided in the first container are supplied, and the mixed particles and the cleaning liquid are stirred to generate a solid-liquid mixed phase flow in which the mixed particles and the cleaning liquid are mixed. A stirring layer for,
A rectifying layer comprising a wavy static mixer for providing a uniform flow of the solid-liquid mixed phase flow supplied from the stirring layer, provided in the upper stage of the stirring layer,
An angle Ψ (0 degree <Ψ <90 degrees) with respect to the horizontal direction for classifying the mixed particles, which is provided in the upper stage of the rectifying layer and supplied with the solid-liquid mixed phase flow passing through the rectifying layer A classification layer having a plurality of inclined pipelines,
The settling device
A second container;
An angle Θ (0 ° <Θ <90 °) with respect to the horizontal direction for settling and agglomerating particles in the solid-liquid mixed phase flow passing through the classification layer provided in the second container A plurality of inclined plates have a laminated inclined plate laminated with a space therebetween, and the solid-liquid mixed phase flow has a sedimentation layer supplied to the side surface of the laminated inclined plate,
An angle Ω (0 degrees <Ω ≦ 10 degrees) with respect to the horizontal direction so that the first container and the second container are connected to each other so that the horizontal direction or the second container side is lowered. A) an agglomeration promoting layer having a plurality of inclined pipe lines;
The washing and classification system in which the solid-liquid mixed phase flow that has passed through the classification layer is supplied to one end of the aggregation promoting layer, and is supplied from the other end to the second container. The agglomeration promoting layer is a laminated plate in which a plurality of horizontal plates are laminated at an interval, and an angle Ω (0 degrees <Ω ≦ 10 degrees) with respect to the horizontal direction so that the second container side is lowered. Inclined angle Ω with respect to the horizontal direction so that a plurality of inclined plates are stacked with a space between them, a structure having a plurality of horizontal cylindrical holes, or the second container side is lowered. The cleaning and classification system according to claim 4, comprising a structure having a plurality of cylindrical holes. The aggregation promoting layer includes a plurality of gable roof-like plates inclined at an angle Φ (0 ° <Φ <90 °) with respect to the horizontal direction downward from the top in the direction of the central axis of the aggregation promoting layer toward both sides. Are inclined at an angle Φ (0 ° <Φ <90 °) with respect to the horizontal direction downward from the top in the direction of the central axis of the laminated inclined plate or the coagulation promoting layer, which are laminated with a space between each other. And a laminated inclined plate in which a plurality of gable roof-shaped plates inclined at an angle Ω (0 degree <Ω ≦ 10 degrees) with respect to the horizontal direction so as to lower the second container side are laminated at intervals. The cleaning and classification system according to claim 4. On the plate at the bottom of the pipe line of the aggregation promoting layer, a vertical plate extending in the direction perpendicular to the central axis of the aggregation promoting layer is in the middle of the height of the pipe line. The cleaning and classification system according to claim 5 or 6, wherein the cleaning and classification system is provided periodically or aperiodically in the direction of the central axis of the layer. The cleaning and classification system according to any one of claims 1 to 7, further comprising a rectifying layer made of a wavy static mixer between the classification layer and the settling device. The cleaning and classification system according to any one of claims 4 to 7 , further comprising a rectifying layer made of a wavy static mixer between the classification layer and the aggregation promoting layer .   The washing and classification system according to any one of claims 1 to 9, wherein the mixed particles are soil.   The cleaning and classification system according to any one of claims 1 to 10, wherein the cleaning liquid is water. A first container;
The mixed particles having a particle size distribution and the cleaning liquid provided in the first container are supplied, and the mixed particles and the cleaning liquid are stirred to generate a solid-liquid mixed phase flow in which the mixed particles and the cleaning liquid are mixed. A stirring layer for,
A rectifying layer comprising a wavy static mixer for providing a uniform flow of the solid-liquid mixed phase flow supplied from the stirring layer, provided in the upper stage of the stirring layer,
A laminar flow layer provided in the upper stage of the rectifying layer for laminating the solid-liquid mixed phase flow that has passed through the rectifying layer;
Provided in the upper part of the laminar flow layer, the solid-liquid mixed phase stream passing through the laminar flow layer is supplied, for classifying the mixed particles, angle [psi (0 degrees to the horizontal <[psi <90 And a classification layer having a plurality of inclined pipelines.   The classification layer includes a structure having a plurality of cylindrical holes inclined at an angle Ψ with respect to the horizontal direction, or a laminated inclined board in which a plurality of plates inclined at an angle Ψ with respect to the horizontal direction are laminated at intervals. The classification device according to claim 12.