JP2013019880A - System for treating contaminated soil containing radioactive material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To construct a system for treating contaminated soil containing radioactive materials which can completely remove radioactive materials from contaminated soil containing hazardous radioactive materials.SOLUTION: In a system for treating contaminated soil containing radioactive materials, alkaline hot water is used as washing water for contaminated soil containing radioactive materials, a radioactive element adsorbent is added in a part of a washing process of the contaminated soil, soil washing water containing solid matter having adsorbed the radioactive elements is separated into completely harmless purified water and sludge, which is solid matter containing harmful radioactive materials, through a solid-liquid separator, the solid matter containing the harmful radioactive materials is enclosed in a radiation shielding capsule to completely prevent the leakage of radiation, and the completely harmless purified water forms a closed circulation circuit to be reused as contaminated soil washing water.

Description

  The present invention relates to treatment of contaminated soil treatment containing radioactive substances, and solidified by solid-liquid separation of only soil containing harmful radioactive substances from washing water using a high-performance washing apparatus and radioactive element absorbent. Solid substances containing harmful radioactive substances are contained in radioactive shielding capsules to prevent leakage to the outside, and the separated washing water is reused again as washing water for contaminated soil in the washing process for contaminated soil containing radioactive substances. The present invention relates to a contaminated soil treatment system containing radioactive substances that can be used.

Previously, the Great East Japan Earthquake that occurred on March 11, 2011, has been examined for safe, reliable, quick and inexpensive methods for detoxifying soil contaminated with oil and heavy metals. It is estimated that 500 million tons of soil contaminated with large amounts of radioactive pollutants in the country.
In general, as a method of treating contaminated soil, there is a method of excavating contaminated soil, removing it out of the contaminated area, and carrying in another fresh soil to replace it. Contamination can be removed with certainty, but when the contaminated soil contains contaminated soil containing radioactive substances, there are problems in the prevention of radioactive leaks during transportation of the removed soil, as well as acceptance and safety issues.

  In addition, as a countermeasure method for the soil contamination problem, there is a method (for example, see Patent Document 1) in which the soil is washed with chemicals or water, the contaminants are extracted and removed, and the washed soil is backfilled in the site. In order to increase the removal rate of pollutants, a large-scale washing facility is required, the cost of the countermeasure facilities is high, and it seems that it cannot be applied to contaminated soil containing radioactive substances.

  Moreover, with the above-described cleaning equipment, not only a sufficient effect cannot be obtained, but it is difficult to reuse the contaminated soil after cleaning, and it has been forced to treat it as industrial waste that has been cleaned. In addition, since chemicals used as cleaning liquids and cleaning agents are generally expensive, using them for the treatment of heavy metal-containing soils that must be treated in large quantities can be costly and economically problematic. It was. Further, in the conventional technique such as the cleaning technique in the above-mentioned Patent Document 1, the cleaning water used for cleaning cannot be “reused”. On the other hand, the effect is not expected so much, and the response to contaminated soil containing radioactive materials is not expected at all.

  Therefore, the present inventor separately used a high-performance, small-space soil washing facility, washed the soil contaminated with harmful substances using peridotite, washed and adsorbed and insolubilized heavy metals and solidified the pollutants. Invented and applied for a pollutant insolubilizing / purifying agent that can be completely detoxified and reused (see Patent Documents 2 and 3). Further, a treatment method for purifying and detoxifying water after use for washing and removing harmful substances in contaminated soil and washing it has been invented (see Patent Document 3). Furthermore, an adsorbent using seaweed has been invented and has already been filed. This has the effect of coagulating and precipitating 90% or more of heavy metals by mixing certain baked seaweed charcoal and shell coagulating precipitants.

  JP 2004-57953 A   JP 2007-283279 A   JP 2011-111617 A

  Therefore, the present invention utilizes the above-described prior art, and further improves the contaminated soil containing the radioactive material, using only a high-performance cleaning device and a radioactive element absorbent to remove only the soil containing the harmful radioactive material. The solid matter containing harmful radioactive material that has been solidified by solid-liquid separation is sealed in a radioactive shielding capsule to prevent leakage to the outside, and the separated wash water is again radioactive as wash water for contaminated soil. It is an object of the present invention to provide a contaminated soil treatment system containing a radioactive substance that can be reused in a cleaning process for contaminated soil containing a substance.

  The invention described in claim 1 uses alkaline warm water for cleaning contaminated soil, and continuously cleans and grinds the contaminated soil. By a first step using a gravity-type cleaning device that peels objects from the surface of soil particles or a forced-polishing type cleaning device that forcibly separates harmful contaminants from the surface of soil particles by friction, and by a dust classification device A second step of removing wood chips, garbage, pumice, etc. in the contaminated soil, and classifying and discharging the soil particles from which harmful substances have been separated in the first step to a second grade particle size group;

  Continuous silt that separates the residual water containing contaminated components from the second step (hereinafter simply referred to as “polluted residual water”) into a solid and contaminated residual water by causing a high-speed tornado-like rotating water stream to wash away high-concentration contaminated soil The third step of discharging into the classification device and discharging the settled fine grained soil and the contaminated residual water separated by the third step are charged into the stirring and cleaning device and further washed to obtain solids and contaminated residues as precipitates. A fourth step of separating into water and returning the precipitate to the third step for reprocessing, and sending the contaminated residual water to the next agglomeration solid-liquid separation device;

  Fifth step of adsorbing radioactive substance from the contaminated residual water by the stirring and coagulating liquid separation device that forcibly introduces the radioactive element adsorbent into the contaminated residual water separated in the fourth step and continuously performs mixing and stirring. And the radioactive element adsorbent that adsorbs the radioactive substance in the fifth step and the centrifuge that separates the residual water, the sludge containing the harmful radioactive substance and the purified water that has been completely detoxified by removing the harmful substance. The cleaning water completely detoxified by the sixth step is returned as the cleaning water in the first step and the third step to form a cleaning circuit, and separated by the sixth step. The sludge containing harmful radioactive material is further dried and solidified, and the surface is coated with a solid agent (for example, “Earth Protector (registered trademark)”) that has a radioactivity shielding function mainly composed of kanlangan. And computing a contaminated soil processing system including a radiation material and performing radioactive shielding process.

  And the invention described in claim 2 is used by maintaining the temperature of alkaline hot water used in the first step at 20 ° C. to 60 ° C., and the invention described in claim 3 The temperature of the washing water used in the fifth step is maintained at 20 ° C. to 50 ° C. for use.

  The invention described in claim 4 is a solid having a radiation shielding function mainly composed of peridotite by further drying and solidifying the sludge containing harmful radioactive substances separated in the sixth step. A capsule made of an agent is sealed with the dried and solidified harmful radioactive material to block and prevent the leakage of radiation to the outside.

  According to the present invention, by using alkaline warm water for cleaning contaminated soil, the ability to peel off radioactive substances attached to the contaminated soil is dramatically improved. Further, by forcibly introducing the radioactive element absorbent material invented by the inventor into the agglomeration solid-liquid separation apparatus in the fifth step, the washing water centrifuged in the sixth step of the treatment step is almost contaminated with radioactive substances. It can be reused as normal washing water.

The sludge containing harmful radioactive substances separated as solid matter is separately sealed in a capsule composed of a solid agent that is further dried and solidified and has a radiation shielding function. It is possible to prevent leakage to the outside.
Therefore, the enormous amount of radioactively contaminated soil introduced in the first step is concentrated to a few percent of the solid matter, so the area for storing the capsule for shielding does not require an enormous area, and prior to disaster recovery work. It has an excellent effect that can quickly remove soil containing harmful radioactive substances.

  In addition to the effects of the present invention, the contaminated soil treatment system of the present invention can continuously process a large amount of contaminated soil reliably in a small space. It can greatly contribute to cost reduction.

  Furthermore, in the continuous treatment method using the adsorptive coagulant of the present invention, off-site drainage treatment is unnecessary, and the radioactive material is hardly attached to the soil discharged from the classification device during the treatment, and the backfilling soil And off-site emissions of hazardous waste can also be reduced

  It is explanatory drawing of the contaminated soil processing system containing the radioactive substance of this invention.

  Hereinafter, although the contaminated soil processing system containing the radioactive substance of this invention is demonstrated, this invention is not limited to these Examples. Moreover, in the following description, about the member, site | part, and structure which have the same function, the same code | symbol may be attached | subjected and description may be abbreviate | omitted.

Hereinafter, an embodiment of a contaminated soil treatment system containing a radioactive substance of the present invention will be described based on the system explanatory diagram of FIG.
Contaminated soil containing radioactive material in the contaminated area (hereinafter simply referred to as “contaminated soil”) A is excavated from the contaminated area with a mechanical force such as a shovel car to separate concrigala, wood pieces, plastic, iron pieces, etc. 20 [deg.] C. supplied to the soil treatment plant by a transporting device, etc., put into the forced cleaning device 1 as the first processing step (hereinafter simply referred to as "the first step"), and supplied from the alkaline hot water manufacturing machine B Mixing with alkaline washing water b of -60 ° C., preferably 50 ° C., continuously crushing and crushing to remove harmful pollutants from the surface of the contaminated soil particles.

The alkaline concentration is adjusted according to the soil quality of the contaminated soil. And this forced-polishing type | mold cleaning apparatus 1 uses the cleaning grinding apparatus which performs crushing and crushing continuously, and the forced-polishing apparatus which peels a harmful contaminant from the surface of a contaminated soil particle by a gravitational impact action. However, in this embodiment, a known cleaning device is used as a hurricane cleaning and grinding device.

Here, the soil 1a from which harmful pollutants have been peeled off from the surface of the contaminated soil particles is supplied to the waste collection and classification device 2 which is the second step to remove wood chips, garbage, pumice, etc. in the contaminated soil. Dispose as Waste C. In the first step, harmful substances are peeled off, and other soil particles are classified into a plurality of particle size groups, for example, 2 groups D and E of 40 mm to 20 mm and 20 mm to 5 mm, and discharged. A commercially available product is also used for the dust collection and classification device 2 used in the second step.

  Residual water containing pollutants and pollutants in the second step (hereinafter simply referred to as “polluted residual water”) 2a causes a high-speed tornado-like rotating water stream to wash highly contaminated soil, To the third step of separation. In the third step, for example, the continuous silt classifier 3 is used, and the precipitated particles (5 mm to 7 μm) are classified and discharged as fine grain soil F. Then, this contaminated residual water 3a is sent to the stirring and washing device 4 in the fourth process, which is the next processing step, and further washed and separated into a solid substance as the precipitate R and the contaminated residual water 4a. R is returned to the above-described continuous silt classifier 3 in the third step and is reprocessed. In addition, a commercially available modified thickener micro valve stirrer is used for the stirring and washing apparatus 4 used in the fourth step.

  The contaminated residual water 4a separated in the fourth step is sent to the stirring coagulation solid-liquid separation device 5 which is the fifth step in which mixing and stirring are continuously performed. As this agglomerated solid-liquid separation device 5, a commercially available hydromixer agglomeration solid-liquid separation device is used, and the earth protector (registered trademark) which is a radioactive element adsorbent separately developed by the present inventors in this fifth step. By forcibly supplying P, the radioactive substance can be absorbed from the contaminated residual water and adsorbed and held.

  The earth protector P is a contaminant adsorbent mainly composed of peridotite, and adsorbs and holds fine contaminants from contaminated residual water. Therefore, in order to separate the earth protector that adsorbs and retains fine contaminants and the residual water, the solid matter containing both and the residual water 5a are sent to the centrifuge 6 which is the next sixth step, and the radioactive material is removed. It is separated into the dewatered sludge G contained and the purified water W that has been detoxified by removing radioactive substances. As the centrifuge used in the sixth step, a commercially available screw decanter type centrifuge is used.

  The detoxified purified water W can be returned to the alkaline hot water washing machine B for the first step or stored in the purified water tank T and reused as washing water for the continuous silt classifier 3. I can do it. The dehydrated sludge G is further dried and solidified and coated with an earth protector, which is a solid agent having a radioactivity blocking function mainly composed of peridotite, or a capsule is formed and enclosed therein. Thus, it is possible to perform the encapsulation process 7 that completely prevents radiation leakage.

  In addition, since the particle | grain soil discharged | emitted by classification in the 2nd process and the 3rd process has almost peeled off the particle | grain surface contaminant, it can be utilized also as soil for backfilling according to an environment.

DESCRIPTION OF SYMBOLS 1 ... Forced polishing type washing | cleaning apparatus 2 ... Dust collection classification apparatus 3 ... Continuous silt classification apparatus 4 ... Stirring washing apparatus 5 ... Stirring aggregation solid-liquid separation apparatus 6 ... Centrifugal separator 7・ ・ ・ Radioactive substance encapsulation treatment A ・ ・ ・ Contaminated soil B ・ ・ ・ Alkaline hot water making machine C ・ ・ ・ Industrial waste D ・ ・ ・ Coarse grain E ・ ・ ・ Medium grain size F ・ ・ ・ Fine grain size P ・ ・・ Radioactive material absorber R ・ ・ ・ Precipitate T ・ ・ ・ Water purification tank (harmless)
G ... Dehydrated sludge W ... Purified water (harmless)

The present invention relates to treatment of contaminated soil treatment containing radioactive substances, and solidified by solid-liquid separation of only soil containing harmful radioactive substances from washing water using a high-performance washing apparatus and radioactive element absorbent. solids containing hazardous radioactive materials, recycled together to prevent leakage to the outside and sealed in radiation shielding capsule, the cleaning process of contaminated soil containing radioactive materials as wash water of the separated wash water again contaminated soil The present invention relates to a contaminated soil treatment system containing radioactive substances that can be used.

Conventionally, measures for detoxifying soil contaminated with oil and heavy metals in a contaminated area safely and reliably, quickly and in large quantities at low cost have been studied .
It is estimated that 500 million tons of contaminated soil from the scattering of a large amount of radioactive pollutants in the Great East Japan Earthquake that occurred on March 11, 2011.
In general, as a method of treating contaminated soil, there is a method of excavating contaminated soil, removing it out of the contaminated area, and carrying in another fresh soil to replace it. Contamination can be removed with certainty, but when the contaminated soil contains contaminated soil containing radioactive substances, there are problems in the prevention of radioactive leaks during transportation of the removed soil, as well as acceptance and safety issues.

In addition, as a countermeasure method for the soil contamination problem, there is a method (for example, see Patent Document 1) in which the soil is washed with chemicals or water, the contaminants are extracted and removed, and the washed soil is backfilled in the site. is, in order to increase the removal rate of pollutants, must be large-scale cleaning equipment, costly to the control equipment, the contaminated soil containing radioactive material would not be corresponds.

  Moreover, with the above-described cleaning equipment, not only a sufficient effect cannot be obtained, but it is difficult to reuse the contaminated soil after cleaning, and it has been forced to treat it as industrial waste that has been cleaned. In addition, since chemicals used as cleaning liquids and cleaning agents are generally expensive, using them for the treatment of heavy metal-containing soils that must be treated in large quantities can be costly and economically problematic. It was. Further, in the conventional technique such as the cleaning technique in the above-mentioned Patent Document 1, the cleaning water used for cleaning cannot be “reused”. On the other hand, the effect is not expected so much, and the response to contaminated soil containing radioactive materials is not expected at all.

  Therefore, the present inventor separately used a high-performance, small-space soil washing facility, washed the soil contaminated with harmful substances using peridotite, washed and adsorbed and insolubilized heavy metals and solidified the pollutants. Invented and applied for a pollutant insolubilizing / purifying agent that can be completely detoxified and reused (see Patent Documents 2 and 3). Further, a treatment method for purifying and detoxifying water after use for washing and removing harmful substances in contaminated soil and washing it has been invented (see Patent Document 3). Furthermore, an adsorbent using seaweed has been invented and has already been filed. This has the effect of coagulating and precipitating 90% or more of heavy metals by mixing certain baked seaweed charcoal and shell coagulating precipitants.

  JP 2004-57953 A   JP 2007-283279 A   JP 2011-111617 A

Therefore, the present invention utilizes the above-described prior art, further improves, and cleans only soil containing harmful radioactive substances using a high-performance washing device and radioactive element absorbent for contaminated soil containing radioactive substances. from water to solid-liquid separation, solids containing hazardous radioactive substances are solidified serves to prevent leakage to the outside and sealed in radiation shielding capsule, separated wash water as wash water again contaminated soil providing contaminated soil processing system including a radioactive substance that can be reused in the cleaning process of contaminated soil containing radioactive materials is an object.

The invention described in claim 1 uses alkaline warm water for cleaning contaminated soil, and continuously cleans and grinds the contaminated soil. Contamination by the first step of using a gravity-type cleaning device that peels off objects from the surface of soil particles, or a forced-polishing type cleaning device that forcibly separates harmful contaminants from the surface of soil particles by friction, and contamination by a waste classifier A second step of removing waste wood, dust, pumice, etc. in the soil, and classifying and discharging the soil particles from which harmful substances have been separated in the first step to a second grade grain soil group;

  Continuous silt that separates the residual water containing contaminated components from the second step (hereinafter simply referred to as “polluted residual water”) into a solid and contaminated residual water by causing a high-speed tornado-like rotating water stream to wash away high-concentration contaminated soil The third step of discharging into the classification device and discharging the settled fine grained soil and the contaminated residual water separated by the third step are charged into the stirring and cleaning device and further washed to obtain solids and contaminated residues as precipitates. A fourth step of separating into water and returning the precipitate to the third step for reprocessing, and sending the contaminated residual water to the next agglomeration solid-liquid separation device;

The radioactive element adsorbent ( see Japanese Patent Application No. 2011-106698) is forcibly added to the contaminated residual water separated in the fourth step, and the mixed agitation solid / liquid separation apparatus continuously performs the stirring from the contaminated residual water. The 5th step of adsorbing radioactive material, and the radioactive element adsorbent that has adsorbed the radioactive material in the 5th step and the centrifuge that separates residual water, remove the sludge containing harmful radioactive material and completely remove the harmful material. Including a sixth step of separating into detoxified purified water, and the cleaning water completely detoxified by the sixth step is returned as cleaning water in the first step and the third step to form a cleaning circuit and the sixth step the sludge containing hazardous radioactive material separated by further drying and solidifying KatachiSei to solid dosage having a radiation shielding function mainly containing peridotite (e.g., "earth protection Tar is a contaminated soil processing system including a radioactive substance, characterized in that by coating the surface by (registered trademark) "performing radiation shielding process.

Then, The invention described in 2 claims a shall be used to hold the temperature of the alkaline hot water to be used in the first step to 20 ° C. to 60 ° C., the invention described in claim 3 The temperature of the washing water used in the fifth step is maintained at 20 ° C. to 50 ° C. for use.

The invention described in claim 4, solid with radiation shielding function mainly further drying and solidifying KatachiSei to peridotite sludge containing hazardous radioactive material separated in the sixth step A harmful radioactive substance dried and solidified is sealed in a capsule composed of an agent to prevent leakage and release of radiation to the outside.

According to the present invention, by using alkaline warm water for cleaning contaminated soil, the ability to peel off radioactive substances attached to the contaminated soil is dramatically improved. Further , by forcibly introducing the radioactive element absorbent invented by the inventor into the agitation / aggregation solid-liquid separation apparatus in the fifth step, the washing water centrifuged in the sixth step of the treatment step is almost contaminated with radioactive substances. It can be reused as normal washing water.

The sludge containing hazardous radioactive material separated as solids, separately, further dried and solidified KatachiSei has been outside of the radiation by enclosing the process placed on the configured capsules in solid agent having a radiation shielding function It is possible to prevent leakage to the
Thus, massive radioactive contaminated soil that has been turned in the first step does not require a huge area also place to store capsule for shielding to be concentrated to the number percent of solids, prior to the disaster recovery work It has an excellent effect that can quickly remove soil containing harmful radioactive substances.

Also, since polluted soil treatment system of the present invention, Runode can be continuously processed to ensure a large amount of contaminated soil in a small space, the in addition to the effects of the present invention, it is possible to process low cost contaminated soil This can greatly contribute to the reduction of processing costs.

Furthermore, in the continuous treatment method using the adsorptive coagulant of the present invention, off-site drainage treatment is unnecessary, and the radioactive material is hardly attached to the soil discharged from the classification device during the treatment, and the backfilling soil also cut with reduced off-site emissions and hazardous waste.

  It is explanatory drawing of the contaminated soil processing system containing the radioactive substance of this invention.

  Hereinafter, although the contaminated soil processing system containing the radioactive substance of this invention is demonstrated, this invention is not limited to these Examples. Moreover, in the following description, about the member, site | part, and structure which have the same function, the same code | symbol may be attached | subjected and description may be abbreviate | omitted.

Hereinafter, an embodiment of a contaminated soil treatment system containing a radioactive substance of the present invention will be described based on the system explanatory diagram of FIG.
Contaminated soil containing radioactive material in the contaminated area (hereinafter simply referred to as “contaminated soil”) A is excavated from the contaminated area with a mechanical force such as a shovel car to separate concrigala, wood pieces, plastic, iron pieces, etc. 20 [deg.] C. supplied to the soil treatment plant by a transporting device, etc., put into the forced cleaning device 1 as the first processing step (hereinafter simply referred to as "the first step"), and supplied from the alkaline hot water manufacturing machine B Mixing with alkaline washing water b of -60 ° C., preferably 50 ° C., continuously crushing and crushing to remove harmful pollutants from the surface of the contaminated soil particles. As the alkaline aqueous solution, for example, a sodium hydroxide (caustic soda) aqueous solution having a pH of about 8 to 12 is used. However, if alkaline warm water is used, the cleaning effect is improved.

The alkaline concentration is adjusted according to the soil quality of the contaminated soil. Then, the forced-polishing washing apparatus 1, the cleaning grinding unit and for performing the sliding crushed and crumpling crush continuously, gravity cleaning apparatus used for separating the toxic contaminants by gravity impact action from the surface of the contaminated soil particles However, in this embodiment, a known cleaning device is used as a hurricane cleaning and grinding device.

Here, the soil 1a from which harmful pollutants have been peeled off from the surface of the contaminated soil particles is supplied to the waste collection and classification device 2 which is the second step to remove wood chips, garbage, pumice, etc. in the contaminated soil. Dispose as Waste C. The soil particles which harmful substances are peeled off in the first step the grain soil groups plurality classes, for example 40mm~20mm and two groups 20Mm～5mm D, is discharged is classified into E. A commercially available product is also used for the dust collection and classification device 2 used in the second step.

Residual water containing pollutants and pollutants in the second step (hereinafter simply referred to as “polluted residual water”) 2a causes a high-speed tornado-like rotating water stream to wash highly contaminated soil, To the third step of separation. In the third step, for example, the continuous silt classifier 3 is used, and the precipitated particles (5 mm to 7 μm) are classified and discharged as fine grain soil F. Then, this contaminated residual water 3a is sent to the stirring and washing device 4 in the fourth process, which is the next processing step, and further washed and separated into a solid substance as the precipitate R and the contaminated residual water 4a. R is returned to the above-described continuous silt classifier 3 in the third step and is reprocessed. A commercially available modified thickener microbubble stirrer is used for the stirring and washing apparatus 4 used in the fourth step.

The contaminated residual water 4a separated in the fourth step is sent to the stirring coagulation solid-liquid separation device 5 which is the fifth step in which mixing and stirring are continuously performed. As this stirring coagulation solid-liquid separation device 5, a commercially available hydromixer coagulation solid-liquid separation device is used, and Earth Protector (registered trademark) P, which is a radioactive element adsorbent separately developed by the present inventor in this fifth step. By forcibly supplying, the radioactive material can be absorbed from the contaminated residual water and adsorbed and retained.

  The earth protector P is a contaminant adsorbent mainly composed of peridotite, and adsorbs and holds fine contaminants from contaminated residual water. Therefore, in order to separate the earth protector that adsorbs and retains fine contaminants and the residual water, the solid matter containing both and the residual water 5a are sent to the centrifuge 6 which is the next sixth step, and the radioactive material is removed. It is separated into the dewatered sludge G contained and the purified water W that has been detoxified by removing radioactive substances. As the centrifuge used in the sixth step, a commercially available screw decanter type centrifuge is used.

The detoxified purified water W can be returned to the alkaline hot water washing machine B for the first step or stored in the purified water tank T and reused as washing water for the continuous silt classifier 3. I can do it. The dewatered sludge G is further dried and solidified KatachiSei coated with earth protector is a solid agent has a radioactivity shielding 蔽 function mainly of peridotite, or constitute a capsule enclosed therein By doing so, it is possible to perform the encapsulation process 7 that completely prevents radiation leakage.

  In addition, since the particle | grain soil discharged | emitted by classification in the 2nd process and the 3rd process has almost peeled off the particle | grain surface contaminant, it can be utilized also as soil for backfilling according to an environment.

DESCRIPTION OF SYMBOLS 1 ... Forced polishing type washing | cleaning apparatus 2 ... Dust collection classification apparatus 3 ... Continuous silt classification apparatus 4 ... Stirring washing apparatus 5 ... Stirring aggregation solid-liquid separation apparatus 6 ... Centrifugal separator 7・ ・ ・ Radioactive substance encapsulation treatment A ・ ・ ・ Contaminated soil B ・ ・ ・ Alkaline hot water production machine C ・ ・ ・ Industrial waste D ・ ・ ・ Coarse grain E ・ ・ ・ Medium grain soil F ・ ・ ・ Fine grain soil P ... Radioactive material adsorbent R ... Precipitate T ... Water purification tank (harmless)
G ... Dehydrated sludge W ... Purified water (harmless)

Claims (4)

Washing and grinding equipment that uses alkaline hot water to clean contaminated soil and continuously crushes and crushes contaminated soil, and equipment that removes harmful pollutants from the surface of soil particles by gravitational impact action from contaminated soil particles A first step using a gravity-type cleaning device or a forced-polishing type cleaning device that forcibly separates harmful pollutants from the surface of soil particles by friction;
A second step of removing debris, debris, pumice, etc. in the contaminated soil by the waste classifier, and classifying and discharging the soil particles from which harmful substances have been separated in the first step into a plurality of grades of particle size groups;
Continuous silt that separates the residual water containing contaminated components from the second step (hereinafter simply referred to as “polluted residual water”) into a solid and contaminated residual water by causing a high-speed tornado-like rotating water stream to wash away high-concentration contaminated soil A third step of putting into a classifier and classifying and discharging the settled fine-grained soil;
The contaminated residual water separated in the third step is put into an agitation and washing device, further washed to separate into solid matter and contaminated residual water as a precipitate, and the precipitate is returned to the third step again. A fourth step of reprocessing and sending the contaminated residual water to the next agglomeration solid-liquid separator;
The radioactive element adsorbent is forcibly introduced into the sent contaminated residual water separated in the fourth step, and the radioactive substance is adsorbed from the contaminated residual water by the stirring and coagulating solid-liquid separation device that continuously performs mixing and stirring. A fifth step;
Separating the radioactive element adsorbent that adsorbs radioactive substances and the residual water into the sludge containing harmful radioactive substances and the purified water that has been completely detoxified by removing harmful substances. Including a sixth step,
The contaminated soil treatment system containing a radioactive material, wherein the purified water completely detoxified in the sixth step is returned as the washing water in the first step and the third step to constitute a washing circuit.   The contaminated soil treatment system containing a radioactive substance according to claim 1, wherein the temperature of the alkaline hot water used in the first step is kept at 20 to 60 ° C.   The contaminated soil containing a radioactive substance according to claim 1 or 2, wherein the temperature of the washing water used in the fifth step performed by introducing the radioactive element adsorbent is maintained at 20 ° C to 50 ° C. Processing system.   The sludge containing harmful radioactive substances separated in the sixth step is further dried and solidified, and sealed in a capsule composed of a solid agent having a radioactivity shielding function mainly composed of peridotite. A contaminated soil treatment system containing a radioactive substance according to claim 1, 2 or 3.

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