CN212042000U - Heavy metal contaminated soil drip washing system - Google Patents

Abstract

The utility model discloses a heavy metal contaminated soil drip washing system, including being used for separating and rinsing physics screening equipment (4) that pollute soil, this physics screening equipment (4) include the screening unit more than the tertiary, and each screening unit is connected in order from big to small according to the particle diameter scope, and arbitrary level screening unit includes the shale shaker. The utility model discloses an among the heavy metal contaminated soil drip washing system, physics screening equipment (4) are including the screening unit more than tertiary, the multi-stage screening unit will pollute the soil and refine to a plurality of particle size grades, the contaminated soil of every particle size within range of effective control, there is better repairing effect to the higher contaminated soil of fine particle content, relative prior art has had bigger application space, in addition, will pollute soil and refine to a plurality of particle size grades, carry out a lot of screening to polluting soil, wash, the use that can corresponding reduction chemical reagent, avoid producing secondary pollution.

Description

Heavy metal contaminated soil drip washing system

Technical Field

The utility model relates to a pollute soil restoration technical field, in particular to heavy metal contaminated soil drip washing system.

Background

At present, the soil leaching technology is mainly adopted for repairing the heavy metal contaminated soil. The soil leaching technology is that polluted soil is dug and then is transported to soil leaching equipment, then pollutants on the surface of soil particles are removed through clear water or a leaching agent, clean coarse-particle soil is recycled, fine-particle soil enriched with pollutants is treated through other technologies, and finally reduction of the polluted soil is achieved.

The existing common heavy metal soil leaching system comprises a two-stage scrubbing unit, a waste liquid treatment unit and a medicament adding unit, wherein the two-stage scrubbing unit is used for leaching, pulping and screening polluted soil and completing remediation of the polluted soil by reaction with a leaching agent, the waste liquid treatment unit is used for treating and recycling waste liquid and bottom mud to avoid secondary pollution, and the medicament adding unit is used for adding the leaching agent into scrubbing equipment.

The leaching system is provided with two-stage scrubbing units, the sandy soil with relatively more large-particle-size soil particles has a better repairing effect, heavy metals on the surfaces of the large-particle-size soil particles are easier to clean, but the heavy metal polluted soil in China mainly takes clay with relatively more small-particle-size soil particles as a main material, the existing leaching system has a higher difficulty in cleaning the heavy metal pollutants in the soil with more small-particle-size soil particles such as clay, and the addition of a leaching agent not only causes the increase of cost, but also easily causes secondary pollution, so that the application space of the soil leaching technology is further limited.

How to solve the above-mentioned defects in the prior art is a technical problem to be solved urgently by technical personnel in the field.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is to provide a heavy metal contaminated soil drip washing system, has better repairing effect to the higher contaminated soil of fine particle content, and mainly uses the means of physics screening as leading, has reduced chemical reagent's use, can effectively avoid secondary pollution.

In order to solve the technical problem, the utility model discloses a heavy metal contaminated soil drip washing system, including physical screening equipment, physical screening equipment is used for separating and washs contaminated soil, including the screening unit more than the tertiary, each the screening unit is connected in order from big to little according to screening particle diameter scope, arbitrary the screening unit includes the shale shaker.

The utility model discloses an among the heavy metal contaminated soil drip washing system, physical screening equipment includes the screening unit more than the tertiary, multistage screening unit will pollute the soil and divide and refine to a plurality of particle size grades, the quantity of the contaminated soil in effective control every particle size scope, there is better restoration effect to the higher contaminated soil of fine particle content, will pollute the soil through a plurality of screening units and refine to a plurality of particle size grades, carry out a lot of screening, washing to the contaminated soil, can correspondingly reduce the use of chemical reagent, avoid producing secondary pollution; in addition, the system is also suitable for the polluted soil with higher coarse particle content, and has wide application range.

Preferably, at least one of the screening units further includes a cyclone group, the cyclone group includes at least one cyclone, an inlet of the cyclone group is connected to the previous screening unit, a underflow port of the cyclone group is connected to an inlet of the vibrating screen of the same stage, and an overflow port of the cyclone group and an undersize outlet of the vibrating screen of the same stage are simultaneously connected to an inlet of the screening unit of the next stage.

In the physical screening equipment, the polluted soil is leached and screened by matching the cyclone group with the vibrating screen, so that the polluted soil is separated under the action of the cyclone group, and only the polluted soil discharged through the underflow port enters the vibrating screen, so that the influence on the screening effect of the vibrating screen due to the too large quantity of the polluted soil in a part of particle size range can be effectively avoided, and the repairing effect of the polluted soil is further influenced.

Preferably, the physical screening equipment includes one-level screening unit, second grade screening unit and tertiary screening unit, one-level screening unit includes the one-level shale shaker, second grade screening unit includes second grade swirler group and second grade shale shaker, tertiary screening unit includes tertiary swirler group and tertiary shale shaker, the entry of second grade swirler group with the undersize exit linkage of one-level shale shaker, the underflow opening of second grade swirler group with the entry linkage of second grade shale shaker, the overflow opening of second grade swirler group reaches the undersize export of second grade shale shaker simultaneously with the entry linkage of tertiary swirler group, the underflow opening of tertiary swirler group with the entry linkage of tertiary shale shaker.

Preferably, the primary screening unit is used for screening out contaminated soil with a particle size range of 0.5-1mm, the secondary screening unit is used for screening out contaminated soil with a particle size range of 0.2-0.5mm, and the tertiary screening unit is used for screening out contaminated soil with a particle size range of 0.075-0.2 mm.

The shale shaker uses with the swirler cooperation, pollutes soil to different particle diameter scopes and realizes separating and wasing in different stages, can effectively avoid polluting in the partial particle diameter scope that soil quantity is too big and influence the screening effect of shale shaker, in addition, sets up tertiary screening unit and carries out tertiary screening to polluting soil, can effectively guarantee to pollute the restoration effect of soil.

Preferably, the vibrating screen is provided with more than two layers of screens, and the screens in different layers have different sizes.

Each vibrating screen is provided with more than two layers of screen meshes with different sizes, so that the polluted soil in the same particle size range is classified and screened, the screening effect of the vibrating screen is effectively ensured, and the repairing effect of the polluted soil is further improved.

Preferably, still include screening equipment in advance, screening equipment's export in advance with physical screening equipment's entry linkage, screening equipment in advance is used for carrying out the drip washing slurrying to contaminated soil and will pollute soil and sieve into the particle size scope of two above differences in order from big to small, and wherein the contaminated soil of minimum particle size scope passes through screening equipment's export in advance gets into physical screening equipment.

Through connecting the pre-screening equipment, make contaminated soil reentrant physical screening equipment after preliminary screening, on the one hand, can effectively reduce the quantity that gets into contaminated soil in the physical screening equipment, improve the treatment effeciency of physical screening equipment, guarantee to pollute the restoration effect of soil, and on the other hand, the contaminated soil of great particle size scope is sieved through the pre-screening equipment, and the contaminated soil of less particle size scope is washed many times again and is sieved in the physical screening equipment, and the higher contaminated soil of fine particle content has obtained better restoration effect.

Preferably, the pre-screening equipment comprises a pulper, a sand washer and a dry screening machine, wherein an outlet of the pulper is connected with an inlet of the sand washer, the sand washer is provided with a first outlet for outputting contaminated soil with relatively large grain size and a second outlet for outputting contaminated soil with relatively small grain size, the first outlet of the sand washer is connected with an inlet of the dry screening machine, and the second outlet of the sand washer and an outlet under the screen of the dry screening machine are simultaneously connected with an inlet of the physical screening equipment.

The pulping machine is used for washing, pulping and screening polluted soil for the first time, the drying screen is used for screening the polluted soil for the second time, and the pulping machine, the sand washer and the drying screen are matched for pre-screening the polluted soil for multiple times, so that the quantity of the polluted soil entering the physical screening equipment can be effectively reduced, the treatment efficiency of the physical screening equipment is improved, the polluted soil with the minimum particle size range is washed and screened for multiple times in the physical screening equipment, and the polluted soil with high fine particle content obtains a better repairing effect.

Preferably, the continuous stirring tank group is arranged between the pre-screening device and the physical screening device and comprises at least one continuous stirring tank.

Connect continuous agitator tank group between preliminary treatment equipment and physics screening equipment, stir contaminated soil through the agitating unit who sets up in the continuous agitator tank group, make contaminated soil of different particle diameters, contaminated soil and the heavy metal pollutant who pollutes the soil surface separate gradually under the effect of frictional force, improve the clearance of polluting soil particle surface pollutant, and then improve the repair effect who pollutes soil.

Preferably, the device further comprises a pretreatment device, an outlet of the pretreatment device is connected with an inlet of the pre-screening device, the pretreatment device is used for crushing the polluted soil and sequentially screening the polluted soil into more than two different particle size ranges from large to small, wherein the polluted soil in the minimum particle size range enters the pre-screening device.

As above, by connecting the soil pretreatment equipment in the heavy metal contaminated soil leaching system, on one hand, large stones in contaminated soil are screened out, on the other hand, large soil blocks in the contaminated soil are crushed, and after multiple screening, the contaminated soil with the minimum particle size is sent to the subsequent pretreatment equipment, so that the treatment efficiency of the subsequent pretreatment equipment can be effectively improved, and the remediation effect of the contaminated soil is ensured.

Preferably, still include water treatment facilities and sediment treatment facilities, the entry of sediment treatment facilities with the exit linkage of physics screening equipment, the liquid outlet of sediment treatment facilities with the entry linkage of water treatment facilities, the export of water treatment facilities simultaneously with the pulper the sand washer with the water jet equipment of shale shaker connects, is used for the pulper the sand washer with the shale shaker provides the leaching water.

As above, the bottom mud treatment equipment is used for separating the mud with the relatively smallest particle size after the mud is subjected to multistage screening and washing, the water treatment equipment is used for treating the washing water used in the repairing process, and the repaired washing water is discharged into the pulping machine, the sand washing machine and the vibrating screen for recycling, so that secondary pollution can be effectively avoided.

Drawings

FIG. 1 is a schematic diagram of an embodiment of the leaching system for heavy metal contaminated soil according to the present invention;

FIG. 2 is a schematic diagram of the pre-screening apparatus of this embodiment;

FIG. 3 is a schematic diagram of the physical screening apparatus of this embodiment;

FIG. 4 is a schematic view of the bottom mud and water treatment apparatus according to this embodiment.

Wherein, in fig. 1 to 4:

1-pretreatment equipment; 2-pre-screening equipment; 21-pulping machine; 22-a sand washer; 23-removing the dry screen; 3-a continuous stirring tank group; 4-physical screening equipment; 41-primary screening unit; 411-first order vibrating screen; 412-level one cache tank; 421-a second-stage cyclone group; 422-secondary vibrating screen; 423-second level buffer tank; 431-three-stage cyclone group; 432-a tertiary shaker; 433-a third level cache tank; 5-bottom sludge treatment equipment; 51-a settling tank; 52-solid-liquid separation equipment; 6-water treatment equipment; 61-a water treatment tank; 611-heavy metal catching agent dispensing tank; 612-a flocculant dispensing tank; 613-coagulant dosing tank; 62-circulating water tank.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.

In the present specification, mainly taking the example of dividing heavy metal contaminated soil into seven grades according to particle size, large stone blocks, gravels, coarse sand, first medium sand, second medium sand, fine sand and superfine sand are sequentially provided, wherein "large stone blocks" refer to contaminated soil with particle size larger than 100mm, "gravels" refer to contaminated soil with particle size within the range of 10-100mm, "coarse sand" refer to contaminated soil with particle size within the range of 1-10mm, "first medium sand" refers to contaminated soil with particle size within the range of 0.5-1mm, "second medium sand" refers to contaminated soil with particle size within the range of 0.2-0.5mm, "fine sand" refers to contaminated soil with particle size within the range of 0.075-0.2mm, and "superfine sand" refers to contaminated soil with particle size below 0.075 mm. It can be understood that in practical application, the particle size division during heavy metal contaminated soil treatment can be set according to the actual situation requirements, and the leaching system is correspondingly set, but not limited to this.

Referring to fig. 1 to 4, fig. 1 is a schematic diagram of an embodiment of the heavy metal contaminated soil leaching system of the present invention, fig. 2 is a schematic diagram of a pre-screening device 2 in the embodiment, fig. 3 is a schematic diagram of a physical screening device 4 in the embodiment, and fig. 4 is a schematic diagram of a sediment treatment device 5 and a water treatment device 6 in the embodiment.

The utility model provides a heavy metal contaminated soil drip washing system, including being used for separating and rinsing the physics screening equipment 4 who pollutes soil, this physics screening equipment 4 includes the screening unit more than the tertiary, and each screening unit is connected in order from big to small according to screening particle diameter scope, and arbitrary level screening unit includes the shale shaker.

The utility model discloses a heavy metal contaminated soil drip washing system, physical screening equipment 4 includes the screening unit more than tertiary, the multi-stage screening unit will pollute the soil and refine to a plurality of particle size grades, the every particle size within range of effective control pollutes the quantity of soil, it has better repairing effect to guarantee to pollute soil, in addition, will pollute the soil through a plurality of screening units and refine to a plurality of particle size grades, carry out a lot of screening, wash polluted soil, the use that can correspondingly reduce chemical reagent avoids producing secondary pollution.

Of course, in practical application, the physical screening device 4 may specifically include several stages of screening units, which may be determined according to the amount of contaminated soil and the ease of remediation, as long as a good remediation effect of the contaminated soil may be achieved on the basis of reducing the use of chemical reagents.

Furthermore, at least one stage of all the screening units further comprises a cyclone group, the cyclone group comprises at least one cyclone, an inlet of the cyclone group is connected with the previous stage of screening unit, a bottom flow port of the cyclone group is connected with an inlet of the same stage of vibrating screen, and an overflow port of the cyclone group and an under-screen outlet of the same stage of vibrating screen are simultaneously connected with an inlet of the next stage of screening unit.

The polluted soil is leached and screened by matching the cyclone group with the vibrating screen, so that the polluted soil is separated under the action of the cyclone group, and only the polluted soil discharged through the underflow port enters the vibrating screen, so that the influence on the screening effect of the vibrating screen due to the too large quantity of the polluted soil in a part of particle size range can be effectively avoided, and the repairing effect of the polluted soil is further influenced.

It will be understood that the overflow outlet of the cyclone will be smaller in size than the underflow outlet, and that the overflow and underflow outlets of the other devices referred to herein are similar and will not be described again.

It should be noted that, the front and the back in this case are based on the sequence of contaminated soil treatment in practical application, the equipment for the first treatment is the front-stage equipment, and the equipment for the second treatment is the back-stage equipment.

In this embodiment, the physical screening device 4 includes a primary screening unit 41, a secondary screening unit 42, and a tertiary screening unit 43, the primary screening unit 41 includes a primary vibrating screen 411 and a primary buffer tank 412, the secondary screening unit 42 includes a secondary cyclone group 421, second grade shale shaker 422 and second grade buffer tank 423, tertiary screening unit includes tertiary swirler group 431, tertiary shale shaker 432 and tertiary buffer tank 433, the entry of second grade swirler group 421 is through one-level buffer tank 412 and the undersize exit linkage of one-level shale shaker 411, the underflow port of second grade swirler group 421 and the entry linkage of second grade shale shaker 422, the overflow mouth of second grade swirler group 421 and the undersize export of second grade shale shaker 422 are simultaneously through the entry linkage of second grade buffer tank 423 with tertiary swirler group 431, the underflow port of tertiary swirler group 431 and the entry linkage of tertiary shale shaker 432, the overflow mouth of tertiary swirler group 431 and the undersize export of tertiary shale shaker 432 are simultaneously with tertiary buffer tank 433.

The shale shaker uses with the cooperation of swirler group, and different particle diameter scope pollutes soil and realizes separating and wasing in different stages, can effectively avoid polluting in the partial particle diameter scope that soil quantity is too big and influence the screening effect of shale shaker, and simultaneously, tertiary screening unit can carry out tertiary screening to polluting soil, effectively guarantees the restoration effect who pollutes soil.

In practical application, the export of each level screening unit still is connected with the buffer memory jar, links to each other with the back level equipment through the buffer memory jar, on the one hand, can play the effect of transition buffering, and on the other hand makes the soil that gets into back level screening unit more even, guarantees the screening effect.

Specifically, in this embodiment, a water spraying device is disposed on the upper portion of the vibrating screen, and the water spraying device includes a spraying pipe and a nozzle for spraying the spraying water to spray the contaminated soil, and preferably, the pressure of the spraying water sprayed by the nozzle is 0.1-0.3 Mpa.

In this embodiment, the vibrating screen is provided with a double-layer screen, preferably, the size of the upper layer screen of the first-stage vibrating screen 411 is 0.8mm, and the size of the lower layer screen is 0.5 mm; the size of the upper layer screen mesh of the secondary vibrating screen 422 is 0.4mm, and the size of the lower layer screen mesh is 0.2 mm; the size of the upper layer screen mesh of the three-stage vibrating screen 432 is 0.1mm, and the size of the lower layer screen mesh is 0.075 mm.

Of course, in practical application, the number of the screens arranged on the vibrating screen can be one layer or more than two layers, and the vibrating screen is adjusted according to the actual condition of the polluted soil as long as the screening effect of the vibrating screen on the polluted soil can be ensured.

In this embodiment, the cyclone group is formed by connecting a plurality of cyclones in parallel, and in practical application, the number of cyclones in the cyclone group can be adjusted according to factors such as the number and the size of polluted soil.

Referring to fig. 1, the system for leaching heavy metal contaminated soil of the present invention further includes a pre-treatment device 1, a pre-screening device 2, a continuous stirring tank group 3, a bottom mud treatment device 5, and a water treatment device 6.

Wherein, the export of pre-treatment equipment 1 is connected with the entry of pre-screening equipment 2, and pre-treatment equipment 1 is used for breaking contaminated soil and sieves into more than two different particle size scopes in order from big to little, and wherein contaminated soil of minimum particle size scope gets into pre-screening equipment 2 through the export of pre-treatment equipment 1.

Through connecting pre-processing equipment 1 in this heavy metal contaminated soil drip washing system, sieve out the big stone in the contaminated soil on the one hand, on the other hand will pollute the bold soil breakage in the soil, send into subsequent pre-screening equipment 2 with the contaminated soil of minimum particle size after sieving many times, can effectively improve subsequent pre-processing equipment's treatment effeciency, guarantee to pollute the restoration effect of soil.

In this embodiment, the pretreatment apparatus 1 includes a grid for screening out large stones in soil, the size of the grid is preferably 100mm, and a crushing and screening machine for crushing large soil in contaminated soil, preferably, the soil is crushed to a particle size of 100mm or less, the pretreatment apparatus 1 divides the contaminated soil into two particle size ranges of 100mm or more and 100mm or less, and contaminated soil with a particle size range of 100mm or less enters the pre-screening apparatus 2.

Of course, according to the different actual sizes of the contaminated soil, the pretreatment device 1 can use the grating and the crushing and screening machine to pretreat the contaminated soil separately or simultaneously, the number of the grating can be one, or more than two gratings can be matched to screen the contaminated soil for multiple times, and in addition, the pretreatment device 1 can also comprise other pretreatment devices according to actual needs.

The outlet of the pre-screening device 2 is connected with the inlet of the physical screening device 4, the pre-screening device 2 is used for washing and pulping the polluted soil and sequentially screening the polluted soil into more than two different particle size ranges from large to small, wherein the polluted soil in the minimum particle size range enters the physical screening device 4 through the outlet of the pre-screening device 2.

The pre-screening equipment 2 is used for primarily screening the contaminated soil and then conveying the contaminated soil to the physical screening equipment 4, on one hand, the amount of the contaminated soil entering the physical screening equipment 4 can be effectively reduced, the treatment efficiency of the physical screening equipment 4 is improved, and the repairing effect of the contaminated soil is ensured, on the other hand, the contaminated soil in a larger particle size range is screened out through the pre-screening equipment 2, the contaminated soil in a smaller particle size range is leached and screened for many times in the physical screening equipment 4, and the better repairing effect is achieved on the contaminated soil with higher fine particle content.

It should be noted that, when practical application, the utility model discloses a heavy metal contaminated soil drip washing system not only is applicable to the higher clay class contaminated soil of fine particle content, also is applicable equally to the higher sandy contaminated soil of coarse particle content. It should be noted that, no matter which kind of contaminated soil is, basically, the included soil particle size range is basically consistent, relatively speaking, the soil with a high fine particle content is called clay soil, and the soil with a high coarse particle content is called sandy soil, in practical application, the soil with a particle size of less than 0.075mm is considered clay when the content of the soil exceeds 25%, and of course, the specific classification standard can be adjusted accordingly.

Referring to fig. 2, in the present embodiment, the pre-screening device 2 includes a pulper 21, a sand washer 22 and a drying screen 23, an outlet of the pulper 21 is connected to an inlet of the sand washer 22, the sand washer 22 is provided with a first outlet and a second outlet, the two outlets are used for outputting contaminated soil with different particle sizes, wherein the first outlet is used for outputting contaminated soil with a relatively large particle size, the second outlet is used for outputting contaminated soil with a relatively small particle size, the first outlet of the sand washer 22 is connected to an inlet of the drying screen 23, and the second outlet of the sand washer 22 and a screen bottom outlet of the drying screen 23 are simultaneously connected to an inlet of the physical screening device 4.

The pulping machine 21 can be a drum pulping machine, the inner wall of the drum pulping machine is a screen, the inside of the drum pulping machine is further provided with a water spraying device and a soil pushing device, the water spraying device is used for spraying washing water to wash polluted soil and form slurry, preferably, the spraying pressure of the washing water is 0.1-0.3Mpa, the soil pushing device is used for pushing gravel mixed in the polluted soil in the drum pulping machine to an outlet of the drum pulping machine, the discharged gravel can be conveyed to a temporary storage yard through a conveying device, the slurry after being screened off the gravel enters the sand washing machine 22 through an outlet of the inner wall screen, and preferably, the size of the inner wall screen is 10 mm.

Specifically, the inside water jet equipment who sets up of cylinder pulping machine includes the shower, is provided with the shower nozzle on the shower, and the leaching water washes the inside contaminated soil of cylinder pulping machine through the shower nozzle, and soil pusher is spiral guide vane, and of course, in practical application, soil pusher can also adopt other structures.

Specifically, the sand washer 22 may be a spiral sand washer, a flushing pipe is disposed on the spiral sand washer for further flushing the slurry flowing into the spiral sand washer, the outlet water pressure of the flushing pipe may be set to 0.1-0.3MPa, the flushed slurry may enter the continuous stirring tank set 3 through an overflow port (i.e., the aforementioned second outlet), and the coarse sand is conveyed to the drying screen 23 through a spiral auger inside the spiral sand washer via the first outlet.

The drying screen 23 is provided with a screen mesh, coarse sand mixed in the contaminated soil inside the drying screen 23 is screened out through the screen mesh, and the mud after the coarse sand is screened out is conveyed to the continuous stirring tank group 3.

In practical application, the number of the screens arranged on the desiccation removing screen 23 can be adjusted according to the condition of the contaminated soil.

In this embodiment, the pre-screening device 2 performs two-stage pre-screening on the contaminated soil through the pulper 21 and the dewatering screen 23, and it should be noted that in practice, the pre-screening device 2 may include one or more of the pulper 21, the sand washer 22 and the dewatering screen 23 to perform screening of the contaminated soil at different levels according to the number and size of the contaminated soil.

The continuous stirring tank group 3 is arranged between the pre-screening equipment 2 and the physical screening equipment 4, and the continuous stirring tank group 3 comprises at least one continuous stirring tank.

Be provided with agitating unit in the continuous stirring jar, stir the mud after 2 handles of pre-screening equipment through agitating unit, make the contaminated soil of different particle size grades, contaminated soil and the heavy metal pollutant who pollutes the soil surface separate gradually under the effect of frictional force, improve the clearance of polluting soil particle surface pollutant, improve the repair effect who pollutes soil. A mud pump may be provided in the continuous mixing tank, by which the mixed mud is pumped to the physical screening apparatus 4, in this particular embodiment, the primary vibrating screen 411.

In the present embodiment, a plurality of continuous stirring tanks are provided in the continuous stirring tank group 3, and preferably, the number of the continuous stirring tanks is 3 to 5.

Of course, the number of the continuous stirring tanks provided in the continuous stirring tank group 3 may be determined according to the actual condition of the contaminated soil.

Further, an inlet of the bottom mud treatment device 5 is connected with an outlet of the physical screening device 4, a liquid outlet of the bottom mud treatment device 5 is connected with an inlet of the water treatment device 6, and an outlet of the water treatment device 6 is simultaneously connected with the water spraying devices of the pulping machine 21, the sand washer 22 and the vibrating screens of the screening units at all levels, so as to provide washing water for the pulping machine 21, the sand washer 22 and the vibrating screens.

The bottom sludge treatment equipment 5 is used for treating the slurry subjected to multistage screening and washing, and it can be understood that after treatment by the preceding-stage equipment, the slurry entering the bottom sludge treatment equipment 5 is the slurry formed by the polluted soil with the relatively minimum particle size in the whole treatment process, the bottom sludge treatment equipment 5 can be used for separating the slurry, so that the washing water and the bottom sludge in the slurry are relatively separated, and the washing water is conveyed to the water treatment equipment 6 through a liquid outlet; the water treatment equipment 6 carries out restoration treatment on the used leaching water in the restoration process, and discharges the restored leaching water into the pulping machine 21, the sand washing machine 22 and the vibrating screen for recycling, so that secondary pollution can be effectively avoided.

In the present embodiment, the bottom sediment treatment facility 5 includes a settling tank 51 and a solid-liquid separation facility 52, and the water treatment facility 6 includes a water treatment tank 61, a heavy metal scavenger dosing tank 611, a flocculant dosing tank 612, a coagulant dosing tank 613, and a circulation water tank 62.

Specifically, the settling tank 51 is used for settling the slurry conveyed therein so as to separate the bottom sludge and the leaching water, the settling tank 51 is specifically provided with a bottom flow port and an overflow port (i.e., the aforementioned liquid outlet), and the settling tank 51 is connected with the solid-liquid separation equipment 52 through the bottom flow port and is connected with the water inlet of the water treatment tank 61 through the overflow port.

The inside agitator tank that sets up at least three and link to each other of water treatment tank 61, heavy metal capture agent blending tank 611, flocculating agent blending tank 612 and coagulant blending tank 613 are connected with three agitator tank respectively and are used for carrying heavy metal capture agent, flocculating agent and coagulant in the three agitator tank, all be provided with agitating unit in the agitator tank, be used for with the treating agent with the leaching water stirring, guarantee the effect of water treatment, the delivery port of water treatment tank 61 and the entry linkage of circulation water pitcher 62, the delivery port of circulation water pitcher 62 simultaneously with pulping machine 21, sand washer 22 and shale shaker are connected, provide the leaching water for pulping machine 21, sand washer 22 and shale shaker through the centrifugal pump.

Wherein, the settling cask 51 is provided with the swash plate for increase the time that contaminated soil subsides in settling cask 51, settling cask 51 bottom is the toper fill, is used for making settling cask 51 bottom sediment mud deposit more easily, and settling cask 51 is inside to be provided with the power pump, is used for carrying the bed mud of settling cask 51 lower part to solid-liquid separation equipment 52, and solid-liquid separation equipment 52 can make the bed mud of settling cask 51 pump sending into the mud cake, and other repair methods of follow-up adoption are handled the mud cake.

The outlet of the slurry filtrate separated in the treated bottom sludge by the solid-liquid separation device 52 is also connected to the water treatment tank 61 of the water treatment device 6.

In practical application, the solid-liquid separation equipment 52 may be one or a combination of several of a centrifuge, a plate-and-frame filter press or a belt filter press, and the sequence of the components in combination can be set according to actual needs.

The heavy metal catching agent comprises xanthate or dithiocarbamate derivatives; the coagulant comprises aluminum sulfate, titanium trichloride, ferrous sulfate, magnesium sulfate, ferrous sulfide, polyaluminium chloride, polyferric oxide and alum; the flocculating agent comprises polyacrylamide, polypropylene, active silicic acid, sodium alginate, sodium carboxymethylcellulose and phosphoric acid.

Obviously, the sizes of the above mentioned components are all exemplified, and in practical application, the size parameters of the components can be properly adjusted according to different conditions of the polluted soil as long as the treatment effect of the polluted soil can be ensured.

The utility model discloses a heavy metal contaminated soil drip washing system is when using, at first, will pollute soil through the engineering machine tool and carry to preliminary treatment equipment 1, preliminary treatment equipment 1 is to polluting soil and carrying out breakage, screening, the big stone in the contaminated soil is removed by the sieve, the contaminated soil after the screening transports preliminary screening equipment 2 through conveyor, preliminary screening equipment 2 loops through pulping machine 21, sand washer 22, the soil that pollutes is rinsed, the slurrying is taken place to threshing screen 23, and carry out twice preliminary screening to the contaminated soil, remove gravel and coarse sand in the contaminated soil, the contaminated soil of minimum particle size gets into continuous stirring tank group 3 after the preliminary screening, continuous stirring tank group 3 stirs the contaminated soil through the agitating unit, make the contaminated soil of different particle sizes, contaminated soil separates gradually with the heavy metal that pollutes the soil surface, afterwards, carry contaminated soil to physical screening equipment 4, the polluted soil is leached and screened by the three-stage screening unit, first medium sand, second medium sand and fine sand in the polluted soil are sequentially screened out, so that the polluted soil with high fine particle content is well repaired, finally, slurry containing the ultra-fine sand is separated into leached water and mud cakes after being treated by the bottom mud treatment equipment 5, the leached water is repaired by the water treatment equipment 6, and the repaired leached water is conveyed to the pulp maker 21, the sand washer 22 and the vibrating screen in the physical screening equipment 3 for recycling, so that secondary pollution is effectively avoided.

In the treatment process, the engineering machinery can be one or two of an excavator or a loader, the conveying device comprises a blanking hopper and a conveying mechanism, and the conveying mechanism can be a belt conveyor, a scraper conveyor or a spiral conveyor.

It is right above the utility model provides a heavy metal contaminated soil drip washing system has carried out detailed introduction. The principles and embodiments of the present invention have been explained herein using specific examples, and the above descriptions of the embodiments are only used to help understand the method and its core ideas of the present invention. It should be noted that, for those skilled in the art, without departing from the principle of the present invention, the present invention can be further modified and modified, and such modifications and modifications also fall within the protection scope of the appended claims.

Claims (8)

1. The utility model provides a heavy metal contaminated soil drip washing system, includes physical screening equipment (4), physical screening equipment (4) are used for separating and wash contaminated soil, its characterized in that: the physical screening equipment (4) comprises more than three screening units, the screening units are sequentially connected from large to small according to the screening particle size range, and any stage of screening unit comprises a vibrating screen;

at least one stage of the screening units also comprises a cyclone group, the cyclone group comprises at least one cyclone, the inlet of the cyclone group is connected with the screening unit of the previous stage, the underflow port of the cyclone group is connected with the inlet of the vibrating screen of the same stage, and the overflow port of the cyclone group and the undersize outlet of the vibrating screen of the same stage are simultaneously connected with the inlet of the screening unit of the next stage;

still include screening equipment (2) in advance, the export of screening equipment (2) in advance with the entry linkage of physical screening equipment (4), screening equipment (2) in advance are used for carrying out the leaching slurrying to contaminated soil and will pollute soil from big to little screening in order into the particle size scope of two above differences, and wherein the contaminated soil of minimum particle size scope passes through the export of screening equipment (2) in advance gets into physical screening equipment (4).

2. The heavy metal contaminated soil washing system according to claim 1, wherein: the physical screening device (4) comprises a primary screening unit (41), a secondary screening unit (42) and a tertiary screening unit (43), the primary screening unit (41) comprises a primary vibrating screen (411), the secondary screening unit (42) comprises a secondary cyclone group (421) and a secondary vibrating screen (422), the three-stage screening unit (43) comprises a three-stage cyclone group (431) and a three-stage vibrating screen (432), the inlet of the second-stage cyclone group (421) is connected with the undersize outlet of the first-stage vibrating screen (411), the underflow opening of the secondary cyclone group (421) is connected with the inlet of the secondary vibrating screen (422), an overflow port of the second-stage cyclone group (421) and a screen lower outlet of the second-stage vibrating screen (422) are simultaneously connected with an inlet of the third-stage cyclone group (431), and the underflow opening of the third-stage cyclone group (431) is connected with the inlet of the third-stage vibrating screen (432).

3. The heavy metal contaminated soil washing system according to claim 2, wherein: the primary screening unit (41) is used for screening out contaminated soil with the particle size range of 0.5-1mm, the secondary screening unit (42) is used for screening out contaminated soil with the particle size range of 0.2-0.5mm, and the tertiary screening unit (43) is used for screening out contaminated soil with the particle size range of 0.075-0.2 mm.

4. The heavy metal contaminated soil washing system according to any one of claims 1-3, wherein: the vibrating screen is provided with more than two layers of screen meshes, and the screen meshes at different levels have different sizes.

5. The heavy metal contaminated soil washing system according to any one of claims 1-3, wherein: pre-screening equipment (2) including pulper (21), sand washer (22) and take off dry sieve (23), the export of pulper (21) with the entry linkage of sand washer (22), sand washer (22) are provided with the first export that is used for exporting the relatively great contaminated soil of particle size and the second export that is used for exporting the relatively less contaminated soil of particle size, the first export of sand washer (22) with take off the entry linkage of dry sieve (23), the second export of sand washer (22) and take off under the sieve export of dry sieve (23) simultaneously with the entry linkage of physical screening equipment (4).

6. The heavy metal contaminated soil washing system according to any one of claims 1-3, wherein: still including locating pre-screening equipment (2) with continuous stirring jar group (3) between physical screening equipment (4), continuous stirring jar group (3) include at least one continuous stirring jar.

7. The heavy metal contaminated soil washing system according to any one of claims 1-3, wherein: still include preprocessing equipment (1), the export of preprocessing equipment (1) with the entry linkage of pre-screening equipment (2), preprocessing equipment (1) is used for will polluting the soil breakage and from big to little sieve in order and is divided into the particle size scope of two above differences, and wherein the contaminated soil of minimum particle size scope passes through the export of preprocessing equipment (1) gets into pre-screening equipment (2).

8. The heavy metal contaminated soil washing system of claim 5, wherein: still include sediment treatment facility (5) and water treatment facilities (6), the entry of sediment treatment facility (5) with the exit linkage of physics screening equipment (4), the liquid outlet of sediment treatment facility (5) with the entry linkage of water treatment facilities (6), the export of water treatment facilities (6) simultaneously with pulper (21), sand washer (22) and each the water jet equipment of shale shaker is connected, is used for doing pulper (21), sand washer (22) and each the shale shaker provides the shower water.

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