JP6296218B2 - Contaminated soil treatment method and contaminated soil treatment system - Google Patents

Description

  The present invention relates to a contaminated soil treatment method and a contaminated soil treatment system.

  Conventionally, contaminated soil treatment that collects contaminated soil and removes radioactive contaminants has been performed, and methods for removing contaminants such as heavy metals and harmful substances from contaminated soil include wet decontamination methods, Dry decontamination methods (see, for example, Patent Documents 1 and 2). In the wet decontamination method, the contaminated soil is washed with, for example, high-pressure washing water to isolate the contaminants together with the washing water, and the washed soil is returned to the collection site. In the dry decontamination method, soil having a small particle size containing most of the radioactive substance is separated and collected, and the soil having a large particle size is returned to the collection site.

JP 2004-249241 A JP 2001-219155 A

However, each of the conventional wet decontamination method and dry decontamination method has the following problems. First, in the wet decontamination method, a large amount of contaminated water is generated, and a large amount of turbid water treatment is required after washing. In addition, when installing a muddy water treatment plant, construction of a large-scale foundation is indispensable. In addition, the wet decontamination method is not suitable for decontamination of farmland soil, because even high-quality components such as minerals contained in the soil are washed away.
On the other hand, the dry decontamination method uses the property that pollutants are likely to adhere to fine particles in the soil, classifies the soil according to particle size, and collects only fine-grained soil. However, the classification accuracy may vary depending on the state of the soil to be treated, such as the moisture content and soil aggregation.

    The present invention has been made in view of the above-mentioned problems, and the object of the present invention is to prevent the generation of sewage during the treatment of contaminated soil, to efficiently perform decontamination, and to separate the contaminated soil from the soil. The object is to provide a contaminated soil treatment technology capable of efficiently storing materials.

(Aspect of the Invention)
The following aspects of the present invention exemplify the configuration of the present invention, and will be described separately for easy understanding of various configurations of the present invention. Each section does not limit the technical scope of the present invention, and some of the components of each section are replaced, deleted, or further while referring to the best mode for carrying out the invention. Those to which the above components are added can also be included in the technical scope of the present invention.

  (1) A contaminated soil treatment method for separating contaminated soil according to particle size and reducing the volume of finely divided soil to isolate it. While finely pulverizing the particles, while measuring the radiation dose in the centrifugal fluid crusher, the finely ground soil is recovered from the centrifugal fluid crusher, and the radiation dose in the centrifugal fluid crusher falls below a predetermined value. Thereafter, the contaminated soil treatment method for discharging the soil remaining in the centrifugal fluid crusher to the outside of the centrifugal fluid grinder (Claim 1).

  In the contaminated soil treatment method described in this section, the contaminated soil is thrown into a centrifugal fluid crusher to make fine particles. At this time, the soil particle size is adjusted so as to be in a state suitable for the separation of the soil according to the particle size by pulverizing and finely pulverizing and pulverizing the soil to loosen up the soil. . Then, when the agglomerated and loosened soil is classified according to the particle size (classification step), the state of the soil to be treated, such as the moisture content of the collected soil and the agglomeration of the soil This avoids the occurrence of variations in classification accuracy due to the above, and improves classification accuracy.

  Moreover, while collecting fine soil from the centrifugal fluid crusher while measuring the radiation dose in the centrifugal fluid grinder during the refinement of the contaminated soil, a small particle size soil containing most of the radioactive material. However, by being removed from the centrifugal fluid pulverizer, the radiation dose in the centrifugal fluid pulverizer decreases, and the measured radiation dose eventually falls below a predetermined value. If the soil remaining in the centrifugal fluid crusher is discharged to the outside of the centrifugal fluid crusher after the radiation dose in the centrifugal fluid crusher falls below the predetermined value, the radiation dose of the discharged soil is surely the predetermined value. Less than

That is, the contaminated soil treatment method described in this section performs a necessary and sufficient step of separating the soil according to the particle size. For example, if the crushing degree of the soil in the centrifugal fluid crusher is set to be consistent with the soil with a high degree of contamination, the soil with a low degree of contamination contained in the soil to be treated will be crushed more than necessary. As a result, the amount of finely-ground soil recovered increases, resulting in an increase in various work processes required for isolation and an increase in storage locations to be secured. In addition, the amount of residual soil decreases, and the amount of soil returned to the soil collection site decreases.
On the other hand, if the soil to be treated contains soil with a higher degree of contamination than expected, the soil crushing degree in the preset centrifugal fluid crusher becomes insufficient, and the remaining soil As a result, the degree of contamination of the soil discharged to the outside of the centrifugal fluid pulverizer remains high. In such a case, it becomes necessary to return the discharged soil to the classification step again, resulting in a decrease in processing efficiency.

  In this regard, according to the contaminated soil treatment method described in this section, the soil remaining in the centrifugal fluid crusher is discharged from the centrifugal fluid crusher after the necessary minimum crushing and the collection of finely sized soil are performed. At that time, the radiation dose of the discharged soil is surely below a predetermined value. And the excessive decontamination of soil and the lack of decontamination are avoided, and the efficiency improvement of the decontamination work of the contaminated soil is achieved.

(2) Prior to the step of throwing the contaminated soil into a centrifugal fluid crusher and making it fine, the contaminated soil collecting step and the drying step of drying the soil collected in the contaminated soil collecting step,
A contaminated soil treatment method for reducing and isolating fine-grained soil collected in the step of collecting fine-grained soil from the centrifugal fluid crusher and returning the remaining soil to a soil collection site.
In the method for treating contaminated soil described in this section, the soil collected in the contaminated soil collecting step is dried in the drying step, and further, in the crushing and pulverizing step, the agglomeration of the dried soil is loosened and pulverized. Then, the particle size of the dried soil is adjusted to be in a state suitable for the separation of the soil by refining. Then, when the finely divided soil is separated in accordance with the particle size after being agglomerated in the crushing and fine pulverization step, and then the finely divided soil is classified (classification step). Thus, it is possible to avoid the occurrence of variation in classification accuracy due to the state of the soil to be treated, such as the moisture content of the collected soil and the aggregation of the soil, thereby improving the classification accuracy. And among the soils classified in the classification process, the small particle size containing most of the radioactive material in a state where the soil storage is enhanced by reducing the volume and isolating the finely divided soil. The soil is separated and collected. Then, by returning the remaining soil to the soil collection site, soil having a large particle size is returned to the collection site.
And since soil washing | cleaning by the dry-type decontamination method is made | formed by the above each process, by-products, such as contaminated water, do not generate | occur | produce over the whole process. In addition, since necessary components (nutrients, etc.) of the soil are not washed away, the soil after washing is returned to the soil collection site and can be easily reused.

(3) In the above (1) and (2), the fine-grained soil from the centrifugal fluid crusher is collected from above the centrifugal fluid grinder, and the soil remaining in the centrifugal fluid grinder A contaminated soil treatment method in which discharge to the outside of the centrifugal fluid crusher is performed below the centrifugal fluid grinder (Claim 2).
The method for treating contaminated soil described in this section is based on the fact that fine-grained soil is more likely to scatter than coarse-grained (large-grained) soil. The efficiency of collecting finely sized soil is enhanced by scattering the inside and performing the process from above the centrifugal fluid crusher. On the other hand, by discharging the soil remaining in the centrifugal fluid crusher to the outside of the centrifugal fluid grinder, the gravity applied to the remaining soil in the centrifugal grinder is reduced. The centrifugal force is used to discharge the remaining soil without necessarily using a suction device or the like.

  (4) In the above item (3), a recovery opening that forms a circumferential clearance at a position below a wall that constitutes the crushing chamber of the centrifugal fluid crusher, and opens from the clearance above the centrifugal fluid crusher. An air flow toward the slab is generated to collect the fine-grained soil from above the centrifugal fluid pulverizer, and in the circumferential direction formed at a position below the wall constituting the pulverization chamber of the centrifugal fluid pulverizer. The clearance of the soil remaining in the centrifugal fluid crusher is generated by widening the opening width of the clearance and generating an air flow toward the circumferential clearance from the recovery port that opens above the centrifugal fluid grinder. A contaminated soil treatment method in which discharge to the outside of the centrifugal fluid crusher is performed below the centrifugal fluid crusher through the clearance (claim 3).

In the contaminated soil treatment method described in this section, a circumferential clearance is formed at a lower position of the wall constituting the crushing chamber of the centrifugal fluid crusher, and from this clearance to a recovery port that opens above the centrifugal fluid crusher. The air flow toward The finely sized soil in the pulverization chamber rides on the air flow from the lower side to the upper side of the pulverization chamber, floats above the centrifugal fluid pulverizer, and is collected from a recovery port opened above the centrifugal fluid pulverizer.
On the other hand, when the soil remaining in the centrifugal fluid crusher is discharged to the outside of the centrifugal fluid crusher, the clearance opening width is widened and the clearance opening opened above the centrifugal fluid crusher is changed to the circumferential clearance. Generate an air flow toward Then, in addition to the gravity and centrifugal force applied to the remaining soil, the soil remaining in the centrifugal fluid pulverizer is pushed downward by the centrifugal fluid pulverizer via the clearance by being pushed away by the air flow toward the recovery port. It is what is discharged.

(5) In the above item (4) , an airflow classifier is disposed above the crushing chamber of the centrifugal fluid pulverizer, and the fine particle size is passed through the recovery port formed in the airflow classifier. A contaminated soil treatment method for collecting soil from above the centrifugal fluid crusher (Claim 4).
In the contaminated soil treatment method described in this section, the airflow classifier is disposed above the crushing chamber of the centrifugal fluid crusher, and the circumferential direction is formed below the wall that constitutes the crushing chamber of the centrifugal fluid crusher. From this clearance, an air flow toward the recovery port that opens to the airflow classifier is generated. Finely sized soil in the crushing chamber rides on the air flow from the bottom to the top of the crushing chamber and rises to the top of the centrifugal fluid crushing device, and is suitable for soil classification according to the particle size in the airflow classifier It adjusts so that it may be in the state. And the fine-grained soil classified by the airflow classifier is performed from above the centrifugal fluid crusher through the recovery port formed in the airflow classifier. On the other hand, in the airflow classifier, the soil separated from the upward air flow falls again into the crushing chamber of the centrifugal fluid crusher, and further refinement is promoted.

(6) In the above items (1) to (5), the contaminated soil is temporarily stored in a hopper located above the centrifugal fluid crusher, and the centrifugal fluid grinding is performed from the hopper through a center chute. A contaminated soil treatment method in which contaminated soil is introduced into the apparatus (claim 5).
In the contaminated soil treatment method described in this section, the contaminated soil is temporarily stored in a hopper located above the centrifugal fluid crusher, and the contaminated soil is poured into the centrifugal fluid crusher at once from the hopper. After discharging the soil remaining in the centrifugal fluid crusher, the next contaminated soil treatment cycle is started immediately.
Moreover, when the contaminated soil is introduced from the hopper to the inside of the centrifugal fluid crusher, the contaminated soil is hardly attached or deposited between the hopper and the centrifugal fluid crusher through the center chute.

(7) A contaminated soil treatment method in which, in the above items (1) to (6), among the soils classified in the classification step, the fine-grained soil is compressed to reduce the volume.
The contaminated soil treatment method described in this section reduces the storage space in the storage facility and reduces the storage space in the storage facility by compressing and reducing the fine-grained soil among the soil classified in the classification process. This will contribute to the reduction of containers.

(8) In the above item (7), when the soil classified in the classification step is compressed and reduced in volume and packed in a soil storage container, the shape of the container is obtained. A method for treating contaminated soil, which is previously molded.
The contaminated soil treatment method described in this section compresses the soil to reduce the volume, and when it is packed in a container for soil storage, it is molded in advance so as to have the shape of the container, It eliminates the clearance and enhances the volume reduction effect. For example, when a drum can is used as a container for storing soil, the soil is compressed and reduced in volume following the cross-sectional shape of the drum. Then, by completely sealing the storage container, the radioactive material contained in the contaminated soil is prevented from eluting from the inside of the container to the outside.

(9) The contaminated soil treatment method according to (1) to (8), wherein when the crushing and pulverization are performed, soil aggregation is crushed and a surface portion of soil particles is peeled off.
In the contaminated soil treatment method described in this section, when the contaminated soil is crushed and pulverized, the surface portion of the soil particles is peeled off to polish the soil, and the surface portions of the peeled soil particles are finely divided. As a result, it is possible to more effectively obtain the predetermined action of the above items (1) to (8). In other words, since the soil fine particles have a lot of contaminants attached to the surface portion, the soil is gradually pulverized from the surface in such a way that it is ground instead of being pulverized with strong force. If the pulverized and peeled surface portion is separated and separated as fine particles by a classification step, the fine particles to which the contaminants are attached can be separated and isolated very efficiently.

(10) In the above items (1) to (9), the fine-grained soil recovered from the centrifugal fluidized pulverizer and the exhaust gas recovered from the centrifugal fluidized pulverizer together with the soil are separated, and the exhaust A contaminated soil treatment method including a collection step, wherein gas is alternately passed through a plurality of dust collectors arranged in parallel every predetermined time, and fine soil contained in the exhaust gas is collected.
The contaminated soil treatment method described in this section separates fine soil particles and exhaust gas. And the fine soil contained in exhaust gas is collected, and it collect | recovers without leaving contaminated soil. In the process of collecting fine soil contained in the exhaust gas (collection process), when a bag filter is used for the dust collector, the exhaust gas is alternately supplied to a plurality of bag filters arranged in parallel every predetermined time. By passing the filter, it is possible to continue the collection process with another bag filter while cleaning one bug filter, and prevent interruption of the contaminated soil treatment.

(11) A contaminated soil treatment system that separates contaminated soil according to particle size and reduces and isolates fine-grained soil, and includes a centrifugal fluid pulverizer and a recovery port that opens above the centrifugal fluid pulverizer a fine particle collection system for collecting the fine soil particle size through a coarse particle recovery system for recovering residual soil recovered fine soil particle size from the centrifugal flow pulverizer, the radiation amount in the centrifugal flow pulverizer A radioactivity sensor for measuring the flow rate of the wall constituting the crushing chamber of the centrifugal fluid crusher, wherein the centrifugal fluid crusher communicates with the fine particle recovery system at a position above the centrifugal fluid crusher. the lower position, provided with a said radiation sensor, an adjustable circumferential clearance opening width, via a circumferential direction of clearance, the coarse particle collection system and is communicated with the centrifugal flow pulverizer And are dirty contaminated soil treatment system (claim 6).

The contaminated soil treatment system described in this section is for carrying out the contaminated soil treatment method according to the above item (1), and has the same effects as the contaminated soil treatment method according to the above item (1). It is.
That is, the contaminated soil put into the centrifugal fluid crusher is made into fine particles and is recovered from the centrifugal fluid crusher to the fine particle recovery system. Moreover, the remaining soil which collect | recovered the fine particle size soil from the centrifugal fluid crusher is collect | recovered by the coarse particle collection | recovery system | strain through the collection port opened above a centrifugal fluid crusher. Moreover, while the contaminated soil is being refined, the radiation sensor in the centrifugal fluid crusher is measured while measuring the radiation dose by the radioactivity sensor provided at the lower position of the wall constituting the crushing chamber of the centrifugal fluid crusher. Collect fine-grained soil from a fluid mill. For this reason, as the soil with a small particle size containing most of the radioactive substance is removed from the inside of the centrifugal fluid crusher, the radiation dose in the centrifugal fluid crusher decreases, and the measured radiation dose will eventually increase. It will be below the predetermined value. If the soil remaining in the centrifugal fluid crusher is discharged to the outside of the centrifugal fluid crusher after the radiation dose in the centrifugal fluid crusher falls below the predetermined value, the radiation dose of the discharged soil is surely the predetermined value. Less than

(12) In the above item (11), an airflow classifier is integrally provided at a position above the crushing chamber of the centrifugal fluid pulverizer, and the centrifugal separator is provided via the recovery port formed in the airflow classifier. A contaminated soil treatment system in which a fluid pulverizer and the fine particle recovery system communicate with each other (Claim 7).
The contaminated soil treatment system described in this section is for carrying out the contaminated soil treatment method according to the above item (5), and has the same effects as the contaminated soil treatment method according to the above item (5). It is.
(13) In the above items (11) and (12), the contaminated soil is temporarily stored in a hopper located above the centrifugal fluid crusher, and the centrifugal fluid crusher is passed from the hopper through a center chute. A contaminated soil treatment system for introducing contaminated soil into the inside (claim 8).
The contaminated soil treatment system described in this section is for carrying out the contaminated soil treatment method according to the above item (6), and has the same effects as the contaminated soil treatment method according to the above item (6). It is.

(14) In the above items (11) to (13), a plurality of dust collectors arranged in parallel for passing the exhaust gas recovered from the centrifugal fluid pulverization apparatus, and the exhaust gas to the plurality of dust collectors Contaminated soil treatment system including a switching valve for alternately supplying.
The contaminated soil treatment system described in this section separates the soil collected from the centrifugal fluid crusher and the exhaust gas, and collects the fine soil contained in the exhaust gas with a dust collector, leaving the contaminated soil. It will be collected without any problems. When a bag filter is used for a dust collector, exhaust gas is passed through a plurality of bag filters arranged in parallel alternately at predetermined intervals, thereby cleaning the bag filter and exhausting it with another bag filter. The work (collection process) which collects the fine soil contained in is continued and the interruption of the contaminated soil treatment is prevented.

(15) In the above item (14), exhaust gas is alternately passed through each of the dust collectors arranged in parallel to the pipe connecting the recovery port of the centrifugal fluid crusher and the dust collector and the outlet pipe of the dust collector. Contaminated soil treatment system with a switching valve
The contaminated soil treatment system described in this section allows the dust collector that does not pass exhaust gas to be cleaned while switching the switching valve and continues the collection process by the dust collector that passes exhaust gas. is there. Valve switching timing and switching and dust collector cleaning operations are performed periodically, for example, at regular intervals. Further, the switching operation may be either manual or automatic.

(16) The contaminated soil treatment system according to (14) or (15), wherein a pipe connecting the recovery port of the centrifugal fluid crusher and the dust collector is provided with a cyclone.
The contaminated soil treatment system described in this section separates fine soil contained in exhaust gas by a cyclone provided in a pipe connecting a recovery port of a centrifugal fluid crusher and a dust collector. The cyclone introduces exhaust gas into a conical container whose diameter is reduced downward, and drops and collects fine soil in the process of turning the exhaust gas along the inner wall of the container. And about the fine soil which cannot be separated by a cyclone, it is sent to the dust collector together with the exhaust gas. For this reason, the amount of fine soil contained in the exhaust gas that has passed through the cyclone is reduced, and the amount of fine soil sent to the dust collector is reduced, so that the time interval for cleaning the dust collector is extended, and the total amount of dust that moves into the dust collector is also increased. The amount of heat is reduced, leading to a reduction in damage to the dust collector due to heat.

(17) The contaminated soil treatment system according to (11) to (16), wherein each of the devices is configured to be movable and operates at a soil collection site.
The contaminated soil treatment system described in this section is configured so that each apparatus described in (11) to (16) above is movable, so that each apparatus is operated at a soil collection site, and a dry decontamination method The soil collection, pulverization, and classification steps are performed, and the small particle size soil containing most of the radioactive material is separated and collected, and the remaining soil is returned to the collection site. Further, for example, each device is mounted on a trailer loading platform or a special vehicle on which each device is mounted is configured so that each device described in the items (11) to (16) can be moved. . These trailers and special vehicles are mounted separately according to the size of each device, or a plurality of types (or all) are mounted on one vehicle, and at the soil collection site, It is arranged so that a predetermined work process is carried out smoothly. Moreover, when this system is installed at a soil collection site, no foundation work or the like is required, the construction period required for installation is short, and it is easy to move to a different soil collection site and operate.

  Since the present invention is configured as described above, wastewater is not generated during the treatment of contaminated soil, and it is possible to efficiently decontaminate and efficiently store pollutants separated from the soil. .

It is a flowchart which shows the contaminated soil processing method which concerns on embodiment of this invention. It is a block diagram which shows schematic structure of the contaminated soil processing system which concerns on the contaminated soil processing method of FIG. It is a block diagram which shows the application example of the contaminated soil processing system shown by FIG. It is sectional drawing which shows typically the structure of the classification apparatus of the contaminated soil processing system shown by FIG. 2, FIG. It is a fragmentary sectional view which shows the characteristic part which concerns on embodiment of this invention of the centrifugal fluid crushing apparatus shown by FIG. 4, (a) is the clearance of the circumferential direction formed in the downward position of the wall which comprises a crushing chamber. (B) shows the installation part of a radioactivity sensor about the structure part which changes opening width. It is a schematic cross section which shows the basic structure of the centrifugal fluid crushing apparatus which comprises the classification apparatus shown by FIG. (A) is sectional drawing which shows a mode that the fine particle size soil is collect | recovered in the classification apparatus shown by FIG. 4, (b) is a mode which discharges | emits the soil which remains in a centrifugal fluid crusher. It is a schematic diagram which shows the hopper of the contaminated soil processing system shown by FIG. 2, FIG. 3, a center chute, and the centrifugal fluid crushing apparatus. It is a schematic diagram which shows an example of the compression apparatus used for compression molding of contaminated soil. The image at the time of comprising the contaminated soil processing system which concerns on embodiment of this invention so that a movement is shown is shown, (a), (b) is an image figure of the special vehicle carrying each apparatus which comprises this system It is.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings.
The contaminated soil treatment method according to the embodiment of the present invention includes the steps shown in FIG. 1 and will be described below in order. In addition, this method is implemented by the contaminated soil processing system 1 shown by FIG. The difference between FIG. 2 and FIG. 3 lies in the difference (FIG. 2) and absence (FIG. 3) of the cyclone 161 in the fine particle collection system 281 of the collection means 28 described later. Moreover, in the following description, the case where soil is contaminated with radioactive substances, such as cesium 137, is illustrated.

S100 (contaminated soil collection step): Collects contaminated soil. Depending on the soil, using an appropriate civil engineering machine such as a backhoe, or if necessary, from the ground surface to an appropriate depth. It is a process of collecting soil.
S110 (drying step): When adjustment of the moisture content of the soil collected in the contaminated soil collecting step (S100) is necessary, the soil is dried. In this step, an appropriate drying device such as a so-called stirring / drying device is used.
S120 (classification step): This is a step in which the agglomeration of the soil dried in the drying step (S110) is crushed and pulverized using the classification device 20 (see FIG. 4), and classified according to the particle size. In addition, while finely contaminating soil, while measuring the radiation dose in the classification device 20 (see FIG. 4), finely sized soil (fine particles) is collected from the classification device 20, and After the radiation dose falls below a predetermined value, the remaining soil (coarse particles) is discharged to the outside of the classifier 20. The classification device 20 according to the embodiment of the present invention will be described later.
In this step, it is preferable that the soil is gradually pulverized from the surface in such a manner that the soil is not pulverized all at once with a strong force. This is because the soil fine particles put into the centrifugal fluid crusher 4 (described later) constituting the classifier 20 have a lot of contaminants attached to the surface portion, so that the surface portion is peeled off. This is because if the separated surface portion is separated and separated as fine particles by fine grinding so as to polish, the fine particles to which the contaminants adhere can be separated and isolated very efficiently.

Here, the configuration of the contaminated soil treatment system 1 will be described with reference to FIG. In addition, each following apparatus structure shows the example of an apparatus suitable for this Embodiment, and it can replace with the apparatus which show | plays the same function suitably, respectively, and can comprise the contaminated soil processing system 1. It is a thing.
The contaminated soil treatment system 1 includes a hopper 22 for temporarily storing the contaminated soil dried in the above-described drying step S110. The hopper 22 is located above the classification device 20, and the contaminated soil stored in the hopper 22 is introduced into the classification device 20 by the center chute 24. Furthermore, the classification device 20 is provided with a radioactivity sensor 26 for measuring the radiation dose in the device. In addition, the contaminated soil treatment system 1 uses the fine particle recovery system 281 and the remaining fine particles collected from the classification device 20 as the collection means 28 for collecting fine particle (fine particles) from the classification device 20. And a coarse particle collection system 282 for collecting soil (coarse particles).

  As shown in FIG. 4, the classifier 20 is configured by integrating an airflow classifier 6 at a position above the crushing chamber of the centrifugal fluid crusher 4. Here, an example of the basic structure of the centrifugal fluid crushing device 4 will be described with reference to FIG. 6, and also improvements regarding application to the classifying device 20 according to the embodiment of the present invention will be described with reference to FIG. 4 and FIG. Reference is made to FIG.

As illustrated in FIG. 6, the centrifugal fluid crusher 4 has an outer peripheral ring 407 attached to the inside of a casing 408 covering the main body portion via a connecting member 409. Reference numeral 410 denotes a pedestal, which pivotally supports the rotating dish 406 via a bearing 411. The rotating shaft 402 is driven by a power source such as an electric motor via a speed reduction mechanism or the like. In the center portion of the ceiling 408 a of the casing 408, a soil input pipe 412 is installed, and an opening 413 is provided so as to surround the input pipe 412. In the example of FIG. 6, the duct 414 is connected to the opening 413. However, in application to the classification device 20 according to the present embodiment, as shown in FIG. 4, instead of the ceiling 408a of the casing 408. In addition, the airflow classifier 6 is integrally provided.
The outer ring 407 is lined with a liner, and a large number of slits or small holes 415 are formed so as to penetrate the wall surface. A side cover 416 is annularly provided between the bottom of the outer surface of the outer peripheral ring 407 and the inner surface of the casing 408, and an air introduction chamber 417 is defined between the side cover 416, the casing 408 and the outer surface of the outer peripheral ring 407. Thus, air can be introduced from the air introduction pipe 418. Note that the upper end of the side cover 416 is tightly fixed to the outer side surface of the outer peripheral ring 407.

A clearance 419 is secured between the outer peripheral edge of the rotating plate 406 and the bottom inner peripheral surface of the outer peripheral ring 407. The clearance 419 is annularly arranged so that the bottom cover 420 covers the lower side of the clearance 419. In the present embodiment, air can be introduced into the bottom cover 420 by perforating the side lower bar 416 or connecting an air introduction pipe.
The bottom cover 420 and the air introduction chamber 417 are connected to a pipeline 421 for extracting and transporting coarse particles from the soil. Further, a scraper 422 is installed on the lower side of the outer peripheral edge of the rotating dish 406 so that fine particles dropped in the bottom cover 420 are gathered toward the connecting portion of the extraction conduit 421.
For example, CFMILL (registered trademark) is known as a centrifugal fluidization type grinding device for finely grinding a raw material by putting a ball such as a steel ball in a rotating dish and an outer ring. There are two types: a continuous type that continuously processes a batch type and a batch type that performs batch processing. The batch type is suitable for the embodiment of the present invention.

When contaminated soil is introduced from the introduction pipe 412 of the centrifugal fluid crusher 4 having the above configuration, the ball 423 circulates between the inner wall surface of the outer peripheral ring 407 and the dish surface as the rotating dish 406 rotates. Further, the fine particles are further pulverized by generating a spiral motion such as tying a rope by combining with a rotational motion around the central axis of the rotating plate 406.
The air introduced into the air introduction chamber 417 and the bottom cover 420 from the air introduction pipe 418 flows into the pulverization chamber through the clearance 419, the slit or the small hole 415, and the duct 414 is accompanied by the powder generated by the pulverization. It enters the inside and is sent to the airflow classifier 6.

In the centrifugal fluid crusher 4 of the classifier 20 according to the embodiment of the present invention, the air introduction pipe 418 and the pipe line 421 are not separate pipe lines, but a common introduction / discharge as shown in FIG. It has been replaced with a pipe line 425. Further, the air introduction chamber 417 and the annular side cover 416 for defining the air introduction chamber are not provided, and the introduction / discharge conduit 425 and the clearance 419 are in direct communication. Accordingly, air is introduced into and out of the crushing chamber of the centrifugal fluid crusher 4 through the clearance 419 and the introduction / discharge conduit 425. The introduction / discharge conduit 425 is also used for soil discharge, as will be described later.
Furthermore, as shown in FIG. 5A, the classifier 20 is provided with a hydraulic jack 427 for moving the outer ring 407 up and down with respect to the rotating dish 406. Then, the outer ring 407 is raised with respect to the rotating dish 406 to widen the opening width S of the clearance 419, whereby the soil is discharged to the introduction / discharge conduit 425. The opening width S of the clearance 419 is changed at least within a range of 10 to 30% of the minimum ball diameter of the ball 423 such as a steel ball. However, in order to further increase the soil discharge efficiency, the ball 423 has a clearance 419. The opening width S may be made wider within a range that is not discharged.

In addition, a radioactivity sensor 26 is provided in the introduction / discharge conduit 425 of the centrifugal fluid crushing device 4 of the classification device 20 according to the embodiment of the present invention. In the example of FIG. 4, the radioactivity sensor 26 is provided so as to penetrate the tube wall of the introduction / discharge conduit 425, although it depends on the type of sensor used. Further, as shown in FIG. 5 (b), the radioactivity sensor 26 is inserted into any one of the plurality of introduction / exhaust conduits 425 so that the radioactivity sensor 26 and the contaminated soil are in direct contact. In order to prevent this, the cover 26a such as an acrylic plate may be installed so as to close the open end of the introduction / discharge conduit 425.
In addition, as shown in FIG. 4, the soil injection pipe 412 of the centrifugal fluid crushing device 4 of the classification device 20 according to the embodiment of the present invention penetrates the central portion of the airflow type classification device 6. 24 is configured.

The airflow classifier 6 integrally configured above the centrifugal fluid crusher 4 of the classifier 20 according to the embodiment of the present invention is pulverized by the centrifugal fluid crusher 4 (FIGS. 4 and 6). The collected soil is sorted into powders of a required particle size by air current, and the classification principle is roughly classified into gravity classification, inertial force classification, and centrifugal force classification. Centrifugal force classification suitable for mass classification of powders includes a free vortex type that swirls the air flow by making the shape of the classification chamber spiral, and the air flow is forced by rotating blades provided in the classification chamber There is a forced vortex to be swirled and a combination of these two, a free vortex and a forced vortex.
The example illustrated in FIG. 4 is configured inside a cylindrical classification chamber 601 and a dispersion chamber 602 with a reduced diameter, and the lower end of the dispersion chamber 602 is a casing 408 of the centrifugal fluid crusher 4. It is comprised so that it may continue. A vertical cylindrical drive shaft 607 that is rotatably supported is disposed so as to surround the outer periphery of the center chute 24 located at the center of the classification chamber 601. In addition, a large number of classification blades 608 that rotate integrally around the drive shaft 607 are attached. On the outer periphery of the classification blade 608, fixed blades 606 constituting a large number of slit-shaped apertures are fixed concentrically and spaced apart at appropriate intervals, connected to the fixed blade 606 and reduced in diameter downward, and the lower end opens. A guide cone 610 is provided.

  The lower end of the guide cone 610 opens into the dispersion chamber 602, and the soil supplied from the center chute 24 passes through the airflow classifier 6 and falls to the centrifugal fluid crusher 4. Then, the fine particles in the soil finely pulverized by the centrifugal fluid pulverizer 4 rise and are classified in the classification chamber 601. Further, the particles falling along the inner walls of the fixed wing 606 and the guide cone 610 are introduced into the classification air blown from the clearance 419 of the centrifugal fluid crusher 4 and dispersed.

The classification by the airflow classifier 6 is performed by the flow of air that rises while turning inside the apparatus under the influence of the rotary impeller 608 (so-called swirling airflow).
That is, particles that are not in the desired size among the soared particles are lifted and transported by the swirling airflow, and the weight of the particles or the centrifugal force applied to the particles in the swirling airflow Therefore, the airflow deviates from the air flow and cannot reach the fixed wing 606, or even if it reaches the fixed wing 606, it cannot pass through the fixed wing 606 or the rotary impeller 608 and falls and falls in the centrifugal fluid crusher 4. It is crushed again.

The fine particles having a desired size among the soared particles ride on the flow of the swirling airflow, pass through the fixed blades 606 and the rotary impeller 608, and are opened above the classification chamber 601. 20 suction ports 20a are sucked. That is, the recovery port 20a opened to the airflow classifier 6 located above the pulverization chamber of the classifier 20 communicates with the fine particle recovery system 281 of the recovery means 28 shown in FIGS.
On the other hand, coarse particles of the recovery means 28 shown in FIG. 2 and FIG. 3 are provided at a position below the wall constituting the crushing chamber of the centrifugal fluid crushing device 4 via a circumferential clearance 419 whose opening width S can be adjusted. It communicates with the recovery system 282.

As shown in FIGS. 2 and 3, the fine particle collection system 281 includes a plurality of dust collectors 12 arranged in parallel for passing exhaust gas containing fine particles of soil discharged from the classifier 20. I have. In the illustrated example, the dust collector 12 uses two bag filters 12A and 12B. In addition, switching to allow exhaust gas to alternately pass through the recovery port 20a which is also the exhaust gas exhaust port of the classifier 20 and the piping connecting the bag filters 12A and 12B and the outlet piping of the bag filters 12A and 12B. And a valve 14. Furthermore, a switching valve 32 (321) is arranged between the collection port 20a of the classification device 20 and the switching valve 14. This switching valve 32 (321) has a gas flow from the recovery port 20a to the bag filter 12 (V1 open, V2 closed) and an inflow of outside air from the recovery port 20a into the classifier 20 (V1 closed, V2 open). Is switched. Switching of the switching valve 32 (321) may be performed manually, but automatic switching may be performed as appropriate based on the detection signal of the radioactivity sensor 26. Further, in the example of FIG. 2, a cyclone 161 is provided in a pipe connecting the recovery port 20a of the classifier 20 and the bag filters 12A and 12B. On the other hand, the cyclone 161 is not provided in the example of FIG.
2 is an exhaust gas fan, and is operated when a gas flow from the recovery port 20a to the bag filter 12 is formed.

And the fine soil collect | recovered by the bag filters 12A and 12B is sent to the shaping | molding process mentioned later, and is compression-molded by the compression apparatus 8. FIG. In the equipment configuration of the fine particle recovery system 281 shown in FIGS. 2 and 3, the contaminated soil is left by collecting fine soil contained in the exhaust gas discharged from the recovery 20a by the bag filters 12A and 12B. Instead, it is turned to the compression device 8. In addition, exhaust gas is alternately passed through a plurality of bag filters 12A and 12B arranged in parallel at predetermined intervals, so that one bug filter (for example, 12A) is cleaned while the other bug filter (for example, 12A) is cleaned. 12B) continues the operation of collecting fine soil contained in the exhaust gas (collection process) to prevent the soiled soil treatment from being interrupted.
Therefore, as long as at least two bug filters constituting the dust collector 12 are installed in parallel as shown in the drawing, the above-mentioned function is exhibited. However, a larger number of bug filters can be switched as needed. You may do it. In addition, even if a bug house for storing a plurality of bug filters 12A and 12B is installed separately for each bug filter 12A and 12B, two bug filters 12A and 12B are provided in one bug house. It may be arranged. In the present embodiment, the bag filters 12A and 12B are used for the dust collector 12. However, other types of dust collectors having the same function may be installed so as to be operable in parallel and alternately.

Further, the switching of the switching valve 14 and the cleaning of the bag filters 12A and 12B may be performed periodically, for example, at regular intervals, and the switching valve 14 may be switched by a manual operation. However, automatic switching may be performed as appropriate.
Further, in the example of FIG. 2, the fine soil contained in the exhaust gas can be removed upstream of the bag filter 12 by arranging the cyclone 161 in the pipe connecting the collection port 20a of the classifier 20 and the bag filters 12A and 12B. To separate. For this reason, since the fine soil contained in the exhaust gas which passed the cyclone 161 decreases and the fine soil sent to the bag filters 12A and 12B decreases, the time interval which should carry out the cleaning operation of the bag filters 12A and 12B is reduced. The total amount of heat that extends and moves into the dust collector is reduced, which leads to a reduction in damage to the dust collector due to heat.

On the other hand, the coarse particle collection system 282 is also provided with a dust collector 12 for allowing exhaust gas exhausted from the classifier 20 and containing coarse particles of soil to pass therethrough. In the illustrated example, one bag filter 12 </ b> C is used for the dust collector 12 of the coarse particle collection system 282. In addition, a switching valve 32 (322) and a cyclone 16 (162) are provided in a pipe connecting the introduction / discharge pipe 425, which is also an exhaust gas discharge port of the classifier 20, and the bag filter 12C. The switching valve 32 (321) is used for the coarse particle soil and gas flow (V3 open, V4 closed) from the introduction / discharge pipe 425 to the cyclone 16, and the inflow of outside air from the introduction / discharge pipe 425 into the classifier 20 Switching between (V3 closed, V4 open) is performed. Switching of the switching valve 32 (322) may be performed manually, but automatic switching may be performed as appropriate based on the detection signal of the radioactivity sensor 26. 2 is an exhaust gas fan, and is operated when a gas flow from the introduction / discharge pipe 425 to the cyclone 16 and the bag filter 12 is formed.
Then, the coarse particle soil is separated by the cyclone 16, and the soil contained in the exhaust gas that has passed through the cyclone 16 is also fully collected by the bag filter 12 </ b> C.

  Moreover, the input of the contaminated soil into the classifier 20 is temporarily stored in the hopper 22 by the conveying means such as the belt conveyor 40 from the tank 38 shown in FIGS. The amount of contaminated soil input to the hopper 22 is controlled so that, for example, a fixed amount is input to the hopper 22 by attaching an encoder or the like to the drive unit of the belt conveyor 40 and monitoring the feed amount by the belt conveyor 40. Is possible. As shown in FIG. 8, an opening / closing valve 34 is provided at the lower end of the hopper 22, and only when contaminated soil is introduced into the center chute 24 by the opening / closing means 36 such as a double flap damper, a rotary valve, etc. The on-off valve 34 is controlled to open. The contaminated soil stored in the hopper 22 passes through the center chute 24 and is put into the classifier 20 at a stretch.

In FIG. 7A, the contaminated soil is put into the classifier 20, the exhaust gas fan 18 (181) of the fine particle recovery system 281 of the recovery means 28 is operated, and the fine port recovery system 281 is passed through the recovery port 20a. This shows a state in which the gas flow is formed.
The contaminated soil 100 introduced into the classifier 20 through the center chute 24 is crushed and finely pulverized by the centrifugal fluid pulverizer 4. At this time, by operating the exhaust gas fan 18 (181) of the fine particle recovery system 281, the pulverization chamber of the centrifugal fluid pulverizer 4 becomes negative pressure, and is introduced from the introduction / discharge conduit 425 via the switching valve 32 (322). Outside air is introduced, and an air flow is formed from the clearance 419 formed between the outer peripheral edge of the rotating dish 406 and the bottom inner peripheral surface of the outer peripheral ring 407 toward the recovery port 20a. And the gas 102 containing the particulates of contaminated soil passes the airflow classifier 6 in the process which goes to the collection port 20a. Then, the gas 102 containing fine particles of contaminated soil that has passed through the airflow classifier 6 is sent from the recovery port 20 a formed in the airflow classifier 6 to the fine particle recovery system 281 of the recovery means 28. Further, the medium-sized particles 104 that have separated from the gas 102 without passing through the airflow classifier 6 fall again to the centrifugal fluid pulverizer 4 and are crushed and finely pulverized. In the meantime, the radiation dose in the centrifugal fluid crusher 4 is measured by the radioactivity sensor 26. Then, after the radiation dose in the centrifugal fluid crusher 4 falls below a predetermined value, the state shifts to the state of FIG.

  FIG. 7B shows a state in which the exhaust gas fan 18 (182) of the coarse particle recovery system 282 of the recovery means 28 is operated to form a gas flow from the introduction / discharge conduit 425 to the coarse particle recovery system 282. Show. In this state, by operating the exhaust gas fan 18 (182) of the coarse particle recovery system 282, the pulverization chamber of the centrifugal fluid pulverizer 4 becomes negative pressure, and outside air is discharged from the recovery port 20a via the switching valve 32 (321). An air flow is introduced from the clearance 419 formed between the outer peripheral edge of the rotating dish 406 and the bottom inner peripheral surface of the outer peripheral ring 407 toward the introduction / discharge conduit 425. At this time, the outer peripheral ring 407 is moved up and down with respect to the rotating dish 406 by the hydraulic jack 427 to widen the opening width S (see FIG. 5) of the clearance 419, thereby urging the soil to be discharged. Then, the coarse particles of the soil and the gas 108 are sent from the clearance 419 of the centrifugal fluid crusher 4 to the coarse particle recovery system 282 of the recovery means 28.

  Furthermore, an example of the compression device 8 of the fine particle recovery system 281 is shown in FIG. The compression device 8 includes a fine particle compression mechanism 821 for performing the first stage compression from one direction, and a coarse particle compression mechanism for performing the second stage compression from a direction orthogonal to the first stage compression direction. 822. Furthermore, a third compression mechanism 823 for compressing the soil compressed in the coarse particle compression mechanism 822 in the axial direction is provided, and the third compression mechanism 823 is provided with a cylindrical processing cavity 824. The fixed mold 825, the movable mold 826 driven by the hydraulic cylinder 827, the coarse particle fixed mold 829, the coarse particle movable mold 830 driven by the coarse particle hydraulic cylinder 831, the receiving mold 832, and the third liquid The third movable mold 833 driven by the pressure cylinder 834 compresses and reduces the soil recovered in the fine particle recovery system 281 and having a high radioactivity level (molding step).

  Moreover, by forming in advance so as to have the shape of a container for soil storage, the clearance when packed in the container is eliminated, and the volume reduction effect is enhanced. The compression device 8 shown in FIG. 9 compresses and reduces the volume of soil following the cross-sectional shape of the drum can when the drum can is used as a container for soil storage. Then, by completely sealing the storage container, the radioactive material contained in the contaminated soil is prevented from eluting from the inside of the container to the outside.

Now, according to the embodiment of the present invention configured as described above, the following operational effects can be obtained.
The contaminated soil treatment method performed by the contaminated soil treatment system 1 according to the embodiment of the present invention is to throw the contaminated soil into the centrifugal fluid crusher 4 that constitutes the classifying device 20 for fine granulation. . At this time, the agglomeration of the soil is loosened and finely pulverized to be finely divided, so that the soil particle size is adjusted so as to be in a state suitable for the soil classification according to the particle size. And when agglomeration is loosened and the finely divided soil is separated according to the particle size, the moisture content of the collected soil and the classification resulting from the state of the soil to be treated, such as soil agglomeration This avoids the occurrence of variations in accuracy and improves classification accuracy.

  Moreover, the fine particle size from the centrifugal fluid crusher 4 is measured while measuring the radiation dose in the centrifugal fluid crusher 4 with the radioactivity sensor 26 during the refinement of the contaminated soil shown in FIG. When the soil is recovered, the small-diameter soil containing most of the radioactive substance is removed from the inside of the centrifugal fluid crusher 4 so that the radiation dose in the centrifugal fluid crusher 4 is reduced and measured. The radiation dose will eventually fall below a predetermined value. Then, after the radiation dose in the centrifugal fluid pulverizer 4 falls below a predetermined value, the soil remaining in the centrifugal fluid pulverizer 4 is transferred to the outside of the centrifugal fluid pulverizer 4 as shown in FIG. When discharged, the radiation dose of the discharged soil is surely below a predetermined value.

  In the contaminated soil treatment method according to the embodiment of the present invention, the soil collected in the contaminated soil collection step (S100) is dried in the drying step (S110), and further dried in the classification step (S120). By loosening and finely pulverizing and agglomerating the agglomerated soil, the particle size of the dried soil is adjusted to a state suitable for soil separation. Then, when the finely divided soil is separated in accordance with the particle size after the aggregation is loosened in the crushing and pulverizing step, which is thrown into the centrifugal fluid crusher 4, that is, the crushing and pulverizing step (classifying step ), The occurrence of variation in classification accuracy due to the state of the soil to be treated, such as the moisture content of the collected soil and the aggregation of the soil, is avoided, and the classification accuracy is increased. And among the soils classified in the classification process, the small particle size containing most of the radioactive material in a state where the soil storage is enhanced by reducing the volume and isolating the finely divided soil. The soil is separated and collected. Then, by returning the remaining soil to the soil collection site, soil having a large particle size is returned to the collection site.

  In the embodiment of the present invention, by utilizing the fact that finely sized soil is more easily scattered than coarsely sized (largely sized) soil, the finely pulverized soil is recovered by centrifugal fluid crushing device 4. By performing from above, the collection efficiency of finely sized soil is enhanced (FIG. 7A). On the other hand, by discharging the soil remaining in the centrifugal fluid crusher 4 to the outside of the centrifugal fluid crusher 4 (FIG. 7B), the centrifugal crusher 4, it is possible to discharge the remaining soil without necessarily using a suction device or the like using the gravity and centrifugal force applied to the remaining soil. In the embodiment of the present invention, by operating the exhaust gas fan 18 (182) of the coarse particle recovery system 282, the pulverization chamber of the centrifugal fluid pulverizer 4 becomes negative pressure, and is switched via the switching valve 32 (321). Outside air is introduced from the recovery port 20a, and the discharge of the soil remaining in the centrifugal fluid crusher 4 to the outside is promoted.

Further, in the embodiment of the present invention, a circumferential clearance 419 is formed at a lower position of the wall constituting the crushing chamber of the centrifugal fluid crusher 4, and the clearance 419 opens above the centrifugal fluid crusher 4. An air flow toward the recovery port 20a is generated (FIG. 7A). The finely sized soil in the pulverization chamber rides on the air flow from the lower side to the upper side of the pulverization chamber, rises above the centrifugal fluid pulverizer 4, and from the recovery port 20 a that opens above the centrifugal fluid pulverizer 4. It becomes possible to collect.
On the other hand, when the soil remaining in the centrifugal fluid crusher 4 is discharged to the outside of the centrifugal fluid crusher 4, it goes from the recovery port 20 a opened above the centrifugal fluid crusher 4 to the circumferential clearance 419. An air flow is generated (FIG. 7B). Then, in addition to the gravity and centrifugal force applied to the remaining soil, the soil remaining in the centrifugal fluid pulverizer 4 is discharged downward from the centrifugal fluid pulverizer 4 by being pushed away by the air flow flowing from the recovery port 20a. It becomes possible.

  In the embodiment of the present invention, the airflow classifier 6 is disposed above the pulverization chamber of the centrifugal fluid pulverizer 4 and is formed at a position below the wall constituting the pulverization chamber of the centrifugal fluid pulverizer 4. An air flow is generated from the circumferential clearance 419 toward the recovery port 20a that opens to the airflow classifier 6. The finely sized soil in the pulverization chamber rides on the air flow from the lower side to the upper side of the pulverization chamber and rises above the centrifugal flow pulverization device 4. In the airflow classifier 6, the soil classification according to the particle size is performed. It adjusts so that it may be in the state suitable for. And the finely divided soil classified by the airflow classifier 6 is performed from above the centrifugal fluid crusher through the recovery port 20 a formed in the airflow classifier 6. On the other hand, in the airflow classifier 6, the soil separated from the upward air flow falls again into the pulverization chamber of the centrifugal fluid pulverizer 4, and further refinement is promoted.

Furthermore, in the embodiment of the present invention, the contaminated soil is temporarily stored in the hopper 22 located above the classifier 20 including the centrifugal fluid pulverizer 4, and from the hopper 22 into the centrifugal fluid pulverizer 4, By introducing the contaminated soil at once, after the soil remaining in the centrifugal fluid crusher 4 is discharged, the next contaminated soil treatment cycle can be started immediately.
In addition, when the contaminated soil is introduced from the hopper 22 into the centrifugal fluid crusher 4, the contaminated soil adheres and accumulates between the hopper 22 and the centrifugal fluid grinder 4 through the center chute 24. It will be difficult.

Furthermore, as imaged in FIGS. 10 (a) and 10 (b), each of the above-described devices is mounted on a trailer bed so that each of the above-mentioned devices constituting the contaminated soil treatment system 1 can move. Or it is good also as comprising the special vehicle which mounts each apparatus. In these special vehicles 10 etc., according to the size of each device, each device is mounted separately, or a plurality of types (or all) are mounted on one vehicle, and the soil collection site Thus, the predetermined work process is arranged so as to be carried out smoothly. In addition, when the contaminated soil treatment system 1 is installed in the soil collection site, foundation work or the like is not required, the construction period required for installation is short, and it is easy to move to a different soil collection site and operate.
In addition, there is no need for permission to install the contaminated soil treatment system 1, and it is possible to expect secondary effects such as obtaining local consent for installation.
In the embodiment of the present invention, as described above, the contaminated soil treatment method and the contaminated soil treatment system in the case where the soil is contaminated with radioactive materials have been described as examples, but the soil treatment technology for other pollution sources is also supported. It will be understood that this is possible.

  1: Contaminated soil treatment system, 4: Centrifugal fluid crusher, 6: Airflow classifier, 8: Compression device, 12: Dust collector, 12A, 12B: Bag filter, 14: Switching valve, 16: Cyclone, 18: Exhaust gas fan , 20: Classifier, 22: Hopper, 24: Center chute, 26: Radioactivity sensor, 28: Recovery means, 281: Fine particle recovery system, 282: Coarse particle recovery system, S100: Contaminated soil collection process, S110: Drying Process, S120: Classification process

Claims (8)

A contaminated soil treatment method for separating contaminated soil according to particle size and reducing and isolating fine-grained soil,
While the contaminated soil is put into a centrifugal fluid crusher and pulverized and the contaminated soil is refined, while measuring the radiation dose in the centrifugal fluid pulverizer, the fine particle soil from the centrifugal fluid pulverizer And the soil remaining in the centrifugal fluid pulverizer is discharged outside the centrifugal fluid pulverizer after the radiation dose in the centrifugal fluid pulverizer falls below a predetermined value. Processing method. The fine-grained soil is recovered from the centrifugal fluidized pulverizer from above the centrifugal fluidized pulverizer, and the soil remaining in the centrifugal fluidized pulverizer is discharged outside the centrifugal fluidized pulverizer. The contaminated soil treatment method according to claim 1, wherein the method is performed downward of the fluid pulverizer. Forming a circumferential clearance at a lower position of the wall constituting the crushing chamber of the centrifugal fluid crusher, and generating an air flow from the clearance toward a recovery port opened above the centrifugal fluid crusher; Collection of the fine-grained soil is performed from above the centrifugal fluid crusher,
The opening width of the circumferential clearance formed at the lower position of the wall constituting the crushing chamber of the centrifugal fluid crusher is widened, and from the recovery port opened above the centrifugal fluid crusher to the circumferential clearance The soil flowing in the centrifugal fluid crusher is discharged to the outside of the centrifugal fluid grinder to the lower side of the centrifugal fluid grinder via the clearance. The contaminated soil treatment method according to claim 2. An airflow classifier is disposed above the crushing chamber of the centrifugal fluidization grinder, and the centrifugal fluid grinder collects the fine-grained soil through the recovery port formed in the airflow classification device. The contaminated soil treatment method according to claim 3, wherein the method is performed from above. Contaminated soil is temporarily stored in a hopper located above the centrifugal fluid pulverizer, and the contaminated soil is introduced into the centrifugal fluid pulverizer from the hopper through a center chute. The contaminated soil treatment method according to any one of claims 1 to 4. A contaminated soil treatment system that separates contaminated soil according to particle size and reduces and isolates fine-grained soil,
Centrifugal fluid pulverizer, fine particle recovery system for collecting fine-grained soil through a recovery port opened above the centrifugal fluid pulverizer, and residual soil from which fine-grained soil is recovered from the centrifugal fluid pulverizer A coarse particle collection system for collecting the radiation, and a radioactivity sensor for measuring the radiation dose in the centrifugal fluid crusher,
In the upper position of the centrifugal fluid pulverizer, the centrifugal fluid pulverizer communicates with the fine particle recovery system,
The radioactivity sensor is provided at a position below the wall constituting the crushing chamber of the centrifugal flow crushing apparatus, and a circumferential clearance capable of adjusting an opening width is provided, and the centrifugal flow is provided via the circumferential clearance. A contaminated soil treatment system, wherein a pulverizer and the coarse particle recovery system communicate with each other. An airflow classifier is integrally provided at a position above the crushing chamber of the centrifugal fluid pulverizer, and the centrifugal fluid pulverizer and the fine particle recovery system are provided through the recovery port formed in the airflow classifier. The contaminated soil treatment system according to claim 6, wherein Contaminated soil is temporarily stored in a hopper located above the centrifugal fluid pulverizer, and the contaminated soil is introduced into the centrifugal fluid pulverizer from the hopper through a center chute. The contaminated soil treatment system according to claim 6 or 7.

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