JP2014070997A - Soil continuous processing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to separate and treat an enormous amount of removed soils in a short time.SOLUTION: A soil continuous processing system includes: a slurry generating device 5 which mixes the mixed soil containing coarse grain soil whose radiation level is low and fine grain soil whose radiation level is high and grain size is smaller than that of the coarse grain soil with water sprayed from a spray nozzle; a sedimentation separator 6 which separates slurry into the coarse grain soil and suspension water containing the fine grain soil by sedimentation; and a flocculation and separation apparatus 11 which adds a flocculant to the suspension water to perform flocculation and separation of the fine grain soil.

Description

  The present invention relates to a soil continuous treatment system.

  The removed soil collected by the decontamination work includes combustible materials such as grass, trees and fallen leaves, and non-combustible materials such as rubble. In addition, the decontaminated soil includes coarse soil having a low radioactivity level and fine soil having a high radioactivity level. At intermediate storage facilities where radioactive materials are stored for a long period of time, the level of radioactivity is ascertained for each stored item, and after removing combustibles that can be reduced by incineration, management according to the radioactive level of the stored item is performed. There is a need to do. However, when decontaminated soil containing various things as described above is placed in the storage container, the concentration of the radioactive substance in the storage container becomes non-uniform, making it difficult to manage the storage container. In addition, it is necessary to prevent toxic gas and fire due to the decay of mixed organic matter. For this reason, about removal soil, before carrying in to an intermediate | middle storage facility, in a reception and separation facility etc., the separation process according to the radioactivity level or the type of combustible or incombustible is needed.

  For example, Patent Document 1 describes an apparatus capable of cleaning removed soil in the separation treatment of decontaminated soil. By using such an apparatus, unnecessary components such as oil contained in the removed soil can be removed. The separation of the removed soil is performed using such an apparatus as shown in Patent Document 1.

JP 2010-284624 A

  However, as is the case with the device disclosed in Patent Document 1, at present, the devices used for performing the separation treatment of the removed soil are independent of each other. For this reason, the separation treatment of the removed soil can only perform batch processing, and cannot perform continuous processing. Currently, there is a huge amount of removed soil generated. For this reason, a lot of time and cost are required in batch processing. Further, in batch processing, the transfer work between the apparatuses is manually performed by the worker, and the radiation exposure amount of the worker increases.

  The present invention has been made in view of the above-described problems, and an object thereof is to enable a huge amount of removed soil to be separated in a short time.

  The present invention adopts the following configuration as means for solving the above-described problems.

  1st invention is a soil continuous processing system, Comprising: The mixed soil containing a coarse-grained soil with a low radioactivity level and a fine-grained soil with a high radioactivity level and a particle size smaller than the said coarse-grained soil is injected. A slurry generator that mixes with water sprayed from a nozzle to generate a slurry, a settling separator that separates the slurry into the coarse-grained soil and the suspended water containing the fine-grained soil by sedimentation, and the suspended water A configuration is adopted in which a flocculant is added to the flocculent separation device for aggregating and separating the fine-grained soil.

  The second invention adopts a configuration in the first invention, further comprising a muddy water tank for temporarily storing the suspended water discharged from the sedimentation separator and supplying the suspended water to the coagulation separator.

  3rd invention employ | adopts the structure provided with the stirring apparatus which stirs the said suspension water stored in the said muddy water tank in the said 2nd invention.

  According to a fourth aspect of the present invention, in the second or third aspect of the invention, the capacity of the turbid water tank is equal to or greater than the capacity of the storage container filled with the fine-grained soil separated by the coagulation / separation apparatus.

  According to the present invention, a slurry containing a coarse-grained soil having a low radioactivity level and a fine-grained soil having a high radioactivity level is produced in the slurry generator, and the slurry is separated into coarse-grained soil and fine-grained soil in a settling separator. In the flocculating / separating apparatus, a flocculant is added to the suspending water to separate the fine-grained soil. That is, according to the present invention, it is possible to continuously separate coarse-grained soil having a low radioactivity level and fine-grained soil having a high radioactivity level. Therefore, according to the present invention, a huge amount of removed soil can be separated in a short time.

It is the flowchart which showed schematic structure of the soil continuous processing system 1 in one Embodiment of this invention. It is a flowchart for demonstrating operation | movement of the soil continuous processing system 1 in one Embodiment of this invention.

  Hereinafter, an embodiment of a soil continuous treatment system according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size.

  FIG. 1 is a flowchart showing a schematic configuration of a soil continuous treatment system 1 of the present embodiment. As shown in this figure, the soil continuous processing system 1 of the present embodiment includes a vibrating screen 2, a first belt conveyor 3, a hopper 4, a slurry generator 5, a sedimentation separator 6, a first screw conveyor 7, and a second. A belt conveyor 8, a muddy water tank 9, a muddy water pump 10, a flocculation / separation device 11, a second screw conveyor 12, a storage box 13, a return pump 14, a water tank 15, a low pressure pump 16 and a high pressure pump 17 are provided.

  The vibration sieving machine 2 separates the raw soil X1 into the separated soil X2 (mixed soil), the combustible material X3, and the incombustible material X4 by applying vibration to the raw soil X1 that is the removed soil itself. . Here, the fractionated soil X2 includes a coarse-grained soil having a low radioactivity level (sandy soil having a particle size of approximately milliorder) and a fine-grained soil having a smaller particle size and a higher radioactivity level (grain size). Is a mixed soil including a powdery soil of approximately micron order. Such a vibrating sieve 2 separates the separated soil X2 containing the radioactive material into the combustible material X3 and the incombustible material X4 that can be incinerated and reduced in volume.

  The combustible material X3 is made of grass, trees, and fallen leaves, and the incombustible material is made of attached soil or gravel. In the vibrating screen 2, it is not always necessary to separate the combustible material X3 and the non-combustible material X4. That is, the combustible material X3 and the non-combustible material X4 can be separated by another slurry generator.

  The first belt conveyor 3 is disposed on the downstream side of the vibration sieve device 2, continuously conveys the sorted soil X <b> 2 discharged from the vibration sieve device 2, and supplies it to the hopper 4. The hopper 4 is arranged on the downstream side of the first belt conveyor 3, temporarily stores the sorted soil X2 conveyed by the first belt conveyor 3, and continuously generates the sorted soil X2 in a slurry generator. Quantitative supply to 5. The slurry generating device 5 is disposed on the downstream side of the hopper 4, and generates the slurry X5 by causing the separation soil X2 supplied from the first belt conveyor 3 to collide with the collision plate together with water sprayed from the spray nozzle. Since the slurry generator 5 is described in detail in, for example, Japanese Patent Application Laid-Open No. 2010-284624, detailed description thereof is omitted here, but high-pressure water pumped from the high-pressure pump 17 is injected from the injection nozzle. At the same time, it is sprayed along the high-pressure water as the entrained water pumped from the low-pressure pump 16, the separation soil X2 is supplied to these waters, and the slurry is caused to collide with the shock wave and the collision plate caused by the high-speed sprayed water. X5 is generated. According to such a slurry production | generation apparatus 5, a coarse-grained soil and a fine-grained soil are disperse | distributed in water by making it collide with the shock wave and collision board which generate | occur | produce with the water injected at high speed, and, thereby, classification soil Crush the fine soul that exists in X2. Moreover, in the slurry production | generation apparatus 5, coarse-grained soil and fine-grained soil are grind | polished by making a coarse-grained soil and fine-grained soil collide with the shock wave and collision board which generate | occur | produce with the water injected at high speed.

  The sedimentation separator 6 is disposed on the downstream side of the slurry generator 5, and by sedimenting and separating the slurry X5 supplied from the slurry generator 5, the coarse soil X6 and the suspended water X7 containing the fine soil To separate. The sedimentation separator 6 forms, for example, an upward flow in the sedimentation separator 6 that is slower than the sedimentation speed of the coarse-grained soil and faster than the sedimentation speed of the fine-grained soil, and the supernatant liquid containing the fine-grained soil is suspended in the suspended water. The sediment which is discharged as X7 and settles at the bottom is discharged as coarse-grained soil X6.

  The 1st screw conveyor 7 is connected with the discharge port of the coarse grain soil X6 of the sedimentation separator 6, conveys the coarse grain soil X6 discharged | emitted from the sedimentation separator 6 diagonally upward, and leaves a liquid component. Remove only the solid phase. The 2nd belt conveyor 8 is arrange | positioned in the downstream of the 1st screw conveyor 7, and conveys the coarse grain soil X6 discharged | emitted from the 1st screw conveyor 7 to a truck etc., for example.

  The muddy water tank 9 is connected to the discharge port of the suspended water X7 of the sedimentation separator 6, and includes a storage tank 9a and a stirring device 9b. The storage tank 9a is a container that temporarily stores the suspended water X7. The stirring device 9b stirs the suspension water X7 stored in the storage tank 9a. In the present embodiment, the capacity of the storage tank 9a is equal to or greater than the capacity of the storage container in which the fine soil X8 accumulated in the storage box 13 is stored. That is, such a muddy water tank 9 temporarily stores the suspended water X7 discharged from the sedimentation separator 6 and stirs it during the storage.

  The muddy water pump 10 is connected to the muddy water tank 9 and pumps the suspension water X7 stored in the muddy water tank 9 toward the flocculating / separating device 11. The aggregating / separating device 11 is disposed on the downstream side of the muddy water pump 10 and includes an aggregating agent adding device 11a, an aggregating reaction tube 11b, and a centrifugal dehydrator 11c arranged in order from the downstream side. The flocculant adding device 11a adds the flocculant to the suspension water X7. The agglomeration reaction tube 11b temporarily stores the suspension water X7 until the suspension water X7 to which the aggregating agent is added and the fine soil X8 contained in the suspension water X7 aggregates. The centrifugal dehydrator 11c separates the suspended water X7 into fine-grained soil X8 and water X9. That is, such a flocculating / separating apparatus 11 adds a flocculant to the suspension water X7 to flocculate and separate the fine-grained soil X8.

  The second screw conveyor 12 is disposed on the downstream side of the aggregating / separating apparatus 11 and conveys the fine-grained soil X8 discharged from the aggregating / separating apparatus 11 obliquely upward, leaving only the liquid component and only the solid phase component. Take out. The storage box 13 is a container having a radiation shielding effect that is disposed downstream of the second screw conveyor 12 and temporarily stores the fine-grained soil X8 discharged from the second screw conveyor 12.

  The return pump 14 is a pump for pumping the water X9 discharged from the coagulation / separation apparatus 11 toward the water tank 15, and is disposed between the coagulation / separation apparatus 11 and the water tank 15. The water tank 15 temporarily stores the water X9 pumped by the return pump 14. The low-pressure pump 16 is a pump that pumps a part of the water X9 flowing from the coagulation / separation device 11 toward the water tank 15 to the slurry generation device 5 at a lower pressure than the high-pressure pump 17. The water X9 pumped by the low-pressure pump 16 becomes the entrained water in the slurry generator 5. The high-pressure pump 17 is a pump that pumps the water X 9 stored in the water tank 15 to the slurry generator 5 at a higher pressure than the low-pressure pump 16. In the soil continuous treatment system 1 of this embodiment, the return pump 14, the water tank 15, the low-pressure pump 16, and the high-pressure pump 17 generate slurry again from the water used in the slurry generator 5 collected by the centrifugal dehydrator 11c. The system is configured to supply to the device 5 and is a system that circulates most of the water. For this reason, drainage to the outside of the soil continuous treatment system 1 can be minimized, and the possibility of expansion of environmental pollution can be minimized.

  In addition, the soil continuous processing system 1 of this embodiment is provided with the control apparatus and electric power generating apparatus which are not illustrated, the electric power required for each apparatus is produced | generated by the electric power generation apparatus, and each apparatus is controlled by the control apparatus. The

  Then, operation | movement of the soil continuous processing system 1 of this embodiment comprised in this way is demonstrated with reference to the flowchart of FIG. In the following description of the operation, the main body is a control device unless otherwise specified.

  First, the primary sorting of the raw soil X1 is performed (step S1). Here, the raw soil X1 is separated into the separated soil X2 and the mixture of the combustible material X3 and the incombustible material X4 by the vibration sieve device 2. The sorted soil X2 is supplied to the hopper 4 by the first belt conveyor 3 and is temporarily accumulated in the hopper 4.

  Subsequently, the sorting soil X2 is cleaned and polished (step S2). Here, in the slurry generator 5, the fractionated soil X2 supplied from the hopper 4 and the water X9 pumped from the low-pressure pump 16 and the high-pressure pump 17 are collided with the collision plate, so that apparently coarse-grained soil is formed. The visible fine-grained earth soul is crushed to produce a slurry X5 in which the fine-grained soil is homogeneously mixed. Further, by polishing the coarse-grained soil X6, the fine-grained soil adhering to the surface of the coarse-grained soil is peeled off, and a slurry X5 in which the fine-grained soil is further mixed homogeneously is generated.

  Subsequently, classification is performed on the slurry X5 (step S3). Here, the slurry X5 discharged from the slurry generating device 5 is separated into the coarse-grained soil X6 and the suspended water X7 by being settled and separated in the sedimentation separator 6. In addition, the coarse-grained soil X6 is conveyed to a truck etc. via the 1st screw conveyor 7 and the 2nd belt conveyor 8, and is accommodated in an accommodation container (flexible bag) after that.

  Subsequently, flocculation separation (step S4) and dehydration (step S5) are performed on the suspension water X7. Here, the suspended water X7 discharged from the sedimentation separator 6 is pumped to the aggregating / separating device 11 by the turbid water pump 10, the aggregating agent is added by the aggregating agent adding device 11a, and the agglutination reaction tube 11b waits for the agglutination reaction to proceed. Then, the finely divided soil X8 and water X9 are separated by the centrifugal dehydrator 11c. The fine-grained soil X8 is accommodated in an accommodation container such as an accommodation box 13 or a flexible container bag by the second screw conveyor 12. The water X9 is pumped to the water tank 15 by the return pump 14.

  The mixture of the combustible material X3 and the non-combustible material X4 separated in step S1 is subjected to secondary separation using another separation device having a mechanism similar to that of the separation soil X2 (step). S6). Here, the separated combustible material X3 is accommodated in an accommodation container (flexible bag). Moreover, you may return an incombustible material to classification (step 3).

  Next, an effect | action and effect of such a soil continuous processing system 1 of this embodiment are demonstrated.

  The reason for the high radioactivity level of the fine-grained soil is considered to be that the fine-grained soil contains a large amount of silicon, and the molecular structure of silicon is easy to take up cesium atoms and is difficult to separate. According to the soil continuous processing system 1 of the present embodiment, the slurry generator 5 generates the slurry X5 including the coarse soil X6 having a low radioactivity level and the fine soil X8 having a high radioactivity level. The settling separator 6 separates the coarse-grained soil X6 and the suspended water X7 containing the fine-grained soil X8, and the flocculating / separating device 11 adds a flocculant to the suspended water X7 to separate the fine-grained soil X8. That is, according to the soil continuous processing system 1 of the present embodiment, the coarse-grained soil X6 with a low radioactivity level and the fine-grained soil X8 with a high radioactivity level are converted into a slurry generator 5, a sedimentation separator 6, and a coagulation separator. 11 can be continuously separated by interlocking. Therefore, according to the soil continuous processing system 1 of this embodiment, a huge amount of removed soil (raw soil X1) can be separated and processed in a short time.

  Furthermore, according to the soil continuous processing system 1 of this embodiment, in the slurry production | generation apparatus 5, the coarse grain soil X6 and the fine grain soil X8 which are contained in the slurry X5 are equalized. For this reason, it becomes easy to measure and manage the radioactivity levels of the coarse-grained soil X6 and the fine-grained soil X8 in the intermediate storage facility.

  The soil continuous treatment system 1 of the present embodiment further includes a muddy water tank 9 that temporarily stores the suspended water X7 discharged from the sedimentation separator 6 and supplies the suspended water X7 to the flocculation separation device 11. For this reason, for example, even if the concentration of the radioactive substance contained in the raw soil X1 changes and the concentration of the radioactive substance in the suspension water X7 discharged from the sedimentation separator 6 changes abruptly, the turbid water tank 9 Since the suspended water X7 before the concentration change and the suspended water X7 after the concentration change are mixed and discharged further downstream, the concentration change of the fine-grained soil X8 accumulated in the storage box 13 can be moderated. . Therefore, it can suppress that the density | concentration of the storage container which accommodates the fine-grained soil X8 changes suddenly, and management in an intermediate storage facility becomes easy.

  Moreover, in the soil continuous processing system 1 of this embodiment, the stirring apparatus 9b which stirs the suspension water X7 stored in the muddy water tank 9 is provided. For this reason, the density | concentration of the radioactive substance in suspension water X7 can be made more uniform, and the radioactivity density | concentration of fractionated soil can be equalized for every storage unit.

  Moreover, in the soil continuous processing system 1 of this embodiment, the capacity | capacitance of the muddy water tank 9 is supposed to be more than the capacity | capacitance of the storage container with which the fine-grained soil X8 isolate | separated with the aggregation separation apparatus 11 is packed. For this reason, when the fine-grained soil X8 is packed in the storage container, it is possible to prevent the concentration of the radioactive substance stored in one storage container from changing greatly.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the spirit of the present invention.

  For example, in the said embodiment, the structure which isolate | separates the classification soil X2 from the raw soil X1 using the vibration sieve machine 2 was demonstrated. However, the present invention is not limited to this, and the separated soil X2 is separated from the raw soil X1 by using another device, or the separated soil previously separated by an operator or the like by omitting the vibration sieve 2. X2 may be used. Moreover, when the combustible material X3 and the incombustible material X4 are not contained in the raw soil X1, the raw soil X1 may be used as the mixed soil of the present invention, and the vibration sieve device 2 may be omitted.

  DESCRIPTION OF SYMBOLS 1 ... Soil continuous processing system, 2 ... Vibrating sieve machine, 3 ... 1st belt conveyor, 4 ... Hopper, 5 ... Slurry production | generation apparatus, 6 ... Settling separator, 7 ... 1st screw conveyor, 8: Second belt conveyor, 9: Turbid water tank, 9a: Storage tank, 9b: Stirrer, 10: Turbid water pump, 11: Coagulation / separation apparatus, 11a: Coagulant addition apparatus, 11b ... Aggregation reaction tube, 11c: centrifugal dehydrator, 12: second screw conveyor, 13: concrete culvert box, 14: return pump, 15: water tank, 16: low pressure pump, 17: high pressure pump, X1 ... Rough soil, X2 ... Separated soil (mixed soil), X3 ... Combustible material, X4 ... Incombustible material, X5 ... Slurry, X6 ... Coarse-grained soil, X7 ... Suspended water, X8 ... Fine Grain soil, X9 ... water

Claims (4)

A slurry in which a mixed soil containing a coarse-grained soil having a low radioactivity level and a fine-grained soil having a high radioactivity level and a particle diameter smaller than that of the coarse-grained soil is mixed with water jetted from a jet nozzle to form a slurry. A generating device;
A sedimentation separator for separating the slurry into the coarse-grained soil and the suspended water containing the fine-grained soil by sedimentation;
A continuous soil treatment system, comprising: a flocculent separation device that adds a flocculant to the suspended water to clump and separate the fine-grained soil.   The soil continuous treatment system according to claim 1, further comprising a muddy water tank for temporarily storing the suspended water discharged from the sedimentation separator and supplying the suspended water to the coagulation separator.   The soil continuous processing system according to claim 2, further comprising a stirring device for stirring the suspension water stored in the muddy water tank.   4. The soil continuous treatment system according to claim 2, wherein the capacity of the muddy water tank is equal to or greater than the capacity of a storage container filled with fine-grained soil separated by the coagulation / separation apparatus.

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