Soil repairing equipment for heavy metal soil pollution

Abstract

The invention relates to heavy metal soil contaminated soil repairing equipment which comprises a slurry making tank, a feeding hopper used for adding an eluting agent is arranged on the side wall of the slurry making tank, a screen drum shell is arranged at the upper end of the slurry making tank, a screen drum is rotationally connected into the screen drum shell, screen holes are distributed in the drum wall of the screen drum, and the screen holes are communicated with the slurry making tank. A spiral conveying belt is arranged on the inner wall of the screen drum, a solid phase outlet is formed in the discharging end of the screen drum shell, a first driving part is arranged at the upper end of a feeding port of the screen drum shell, a first driving gear is arranged at the output end of the first driving part, and an outer gear ring meshed with the first driving gear is arranged at the feeding end of the screen drum; a spraying pipe connected with an external water source is arranged on the inner top wall of the screen drum shell; by flushing the solid phase, heavy metal in the soil is transferred into the liquid phase, and the large-particle solid phase is finally discharged from the solid phase outlet, so that the soil is fully leached, and secondary pollution caused by the fact that the large-particle solid phase returns to the nature is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of contaminated soil treatment, and in particular to soil repair equipment for heavy metal-contaminated soil. Background Art

[0002] Soil is an important part of the natural environment and the material basis for human survival. However, with the rapid development of social economy, various human activities have an increasingly greater impact on the soil environment, and the problem of heavy metal pollution in soil is becoming increasingly serious. The sources of heavy metal pollution in soil are extensive, mainly from human production and life activities, including mining, smelting, metal processing, chemical industry, waste battery treatment, electronics, leather making and dyeing and other industrial wastes, as well as automobile exhaust emissions, pesticide and fertilizer application, etc. The main types of heavy metals are mercury, cadmium, lead, copper, chromium, arsenic, nickel, iron, manganese, zinc, etc. Since heavy metals cannot be decomposed by soil microorganisms, they are easy to accumulate and converted into more toxic methyl compounds. Some even accumulate in the human body at harmful concentrations through the food chain, seriously endangering human health. Compared with water pollution, heavy metal pollution of the soil environment is more difficult to control and has greater pollution hazards.

[0003] At present, the remediation technologies used for heavy metal soil pollution mainly include physical remediation (turning over soil and imported soil method, etc.), chemical remediation (leaching) and biological remediation (plants and microorganisms). Among them, the physical remediation method is large in engineering workload, time-consuming and labor-intensive, and the cost is too high. The biological remediation method has a long cycle and low efficiency, which affects the normal use of the land. The chemical leaching remediation method can not only be used for in-situ remediation, but also for off-site remediation. It has the advantages of stable treatment effect and thorough remediation. It is the most widely used in the field of heavy metal contaminated soil remediation. It mainly uses leaching agents to extract heavy metals in different forms in the soil, thereby removing the heavy metals in the soil. It has the characteristics of simple operation and low remediation cost, and has good application potential.

[0004] In the prior art, when using the ex situ soil leaching remediation method to treat heavy metal soil pollution, it is necessary to first use a screening machine and a crusher to screen and crush the contaminated soil to remove large solid particles (such as stones) in the soil, and then the screened and crushed soil is leached and filtered. During the screening, a large amount of soil will adhere to the surface of the large solid particles. This soil will be sieved and removed along with the large solid particles, and the heavy metals mixed in it will not be leached, and will return to the self, causing secondary pollution. Summary of the invention

[0005] The embodiment of the present invention provides a soil repair device for heavy metal soil contamination, which can solve the problem in the prior art that a large amount of soil is attached to the surface of large solid particles, and the soil is sieved and removed along with the large solid particles, while the heavy metals doped therein cannot be leached and return to the soil, causing secondary pollution.

[0006] In order to solve the above technical problems, the present invention adopts the following technical scheme: a soil repair equipment for heavy metal soil contamination, comprising a pulping trough, a hopper for adding a washing agent is arranged on the side wall of the pulping trough, a screen drum shell is arranged at the upper end of the pulping trough, a screen drum is rotatably connected to the inside of the screen drum shell, screen holes are arranged on the drum wall of the screen drum, a spiral conveyor belt is arranged on the inner wall of the screen drum, a solid phase outlet is arranged at the discharge end of the screen drum shell, a first driving part is arranged at the upper end of the feed port of the screen drum shell, a first driving gear is arranged at the output end of the first driving part, an outer gear ring meshing with the first driving gear is arranged at the feed end of the screen drum, a spray pipe connected to an external water source is arranged on the inner top wall of the screen drum shell, the spray pipe is arranged parallel to the screen drum, a spray head with a water outlet direction facing downward is arranged on the spray pipe, a water pump is arranged on the spray pipe, a slurry outlet pipe is arranged at the lower end of the side wall of the pulping trough, and a slurry outlet valve is arranged on the slurry outlet pipe.

[0007] Preferably, a metal chain is arranged on the inner wall of the sieve cylinder.

[0008] Preferably, a bracket is provided on the pulping trough, and the bracket is located at the feed end of the screen cylinder. A feeding barrel is provided on the bracket, and a feeding hopper is provided on the feeding barrel. A screw conveyor is rotatably connected to the inside of the feeding barrel, and one end of the feeding barrel extends into the interior of the screen cylinder. A mounting plate is provided at the other end of the feeding barrel, and a second driving part is provided on the mounting plate, and the output end of the second driving part is fixedly connected to the screw conveyor.

[0009] Preferably, a second driving gear is provided at the output end of the second driving part, a second driven gear meshing with the second driving gear is rotatably connected to the outer wall of the feed hopper, a driving bevel gear is coaxially provided with the second driven gear, a first extrusion roller and a second extrusion roller are rotatably connected inside the feed hopper, a first driving pulley is coaxially provided with the first extrusion roller, a first driven pulley is coaxially provided with the second extrusion roller, a first belt is cross-drivenly connected between the first driving pulley and the first driven pulley, and a driven bevel gear meshing with the driving bevel gear is coaxially provided with the first driving pulley.

[0010] Preferably, two slide grooves are provided on two opposite side walls of the feed hopper, two sliders are slidably connected inside the two slide grooves, the second extrusion roller is rotatably connected between the two sliders, a "U"-shaped connecting rod is arranged between the two sliders, a fixed cylinder is arranged on the side wall of the feed hopper, the fixed cylinder is slidably connected inside the fixed cylinder with a "T"-shaped force guiding rod having one end fixedly connected to the "U"-shaped connecting rod, an elastic part is arranged between the "T"-shaped force guiding rod and the inner side wall of the fixed cylinder, and a belt tensioning mechanism is also arranged on the outer side wall of the feed hopper.

[0011] Preferably, the belt tensioning mechanism includes a bearing seat, a tensioning wheel and a tension spring. The bearing seat is vertically slidably connected to the outer wall of the feed hopper. The bearing seat is rotatably connected to the tensioning wheel. The first belt passes around the tensioning wheel. The tension spring is arranged between the bearing seat and the feed hopper.

[0012] Preferably, an adjusting box is provided at the upper end of the fixed cylinder, and a worm is rotatably connected to the adjusting box and passes through its side wall, and a worm wheel is rotatably connected to the adjusting box internally and connected to the worm gear, and a cam is rotatably connected to the fixed cylinder internally and arranged coaxially with the worm wheel, and the "T"-shaped force guide rod is in close contact with the cam surface of the cam under the action of the elastic potential energy of the elastic member.

[0013] Preferably, a first driven gear meshing with an outer gear ring is rotatably connected to the side wall of the pulp making tank, a second driving pulley is coaxially arranged on the first driven gear, a stirring paddle is rotatably connected to the interior of the pulp making tank, a second driven pulley is coaxially arranged on the stirring paddle, and a second belt is transmission-connected between the second driving pulley and the second driven pulley.

[0014] Compared with the prior art, the present invention adopts the coordinated arrangement of a pulping trough, a feeding hopper, a screen drum shell, a screen drum, sieve holes, a spiral conveyor belt, a solid phase outlet, a first driving unit, a first driving gear, an outer gear ring, a spray pipe, a spray head, a water pump, a pulping pipe and a pulping valve. Soil enters the screen drum from the feeding end of the screen drum, the first driving unit drives the first driving gear to rotate, and the first driving gear drives the screen drum to rotate through the outer gear ring. Under the conveying action of the spiral conveyor belt, the soil gradually moves toward the discharge end. The water pump conveys water from an external water source to the spray pipe, and each spray head sprays it into the soil to wash the soil on the surface of the large solid particles. The mud formed during the washing process falls into the pulping trough through the sieve holes. A washing agent is added to the pulping trough through the feeding hopper to mix it with the mud, so that the heavy metals in the soil are transferred to the liquid phase, and the large solid particles are finally discharged from the solid phase outlet, so that the soil is fully washed to avoid the large solid particles returning to nature and causing secondary pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the main structure of the present invention;

[0016] Figure 2 This is a schematic diagram of the front cross-sectional structure of the screen drum of the present invention;

[0017] Figure 3 This is a schematic diagram of the main cross-sectional structure of the feeding tube of the present invention;

[0018] Figure 4 For the present invention Figure 3 A schematic diagram of the structure enlargement in the middle;

[0019] Figure 5This is a schematic diagram of the main cross-sectional structure of the feed hopper of the present invention;

[0020] Figure 6 It is a schematic diagram of the rear view structure of the feed hopper of the present invention.

[0021] In the figure: 1, pulping tank; 2, screen drum shell; 3, screen drum; 4, screen hole; 5, spiral conveyor belt; 6, solid phase outlet; 7, first driving unit; 8, first driving gear; 9, outer gear ring; 10, spray pipe; 11, spray head; 12, water pump; 13, pulp outlet pipe; 14, feeding hopper; 15, bracket; 16, metal chain; 17, feeding drum; 18, mounting plate; 19, second driving unit; 20, spiral conveyor; 21, feeding hopper; 22, second driving gear; 23, first extrusion roller; 24, second extrusion roller; 25, first driving pulley; 26. First driven pulley; 27. First belt; 28. Second driven gear; 29. ​​Active bevel gear; 30. Driven bevel gear; 31. Slide; 32. Sliding block; 33. "U"-shaped connecting rod; 34. Fixed cylinder; 35. "T"-shaped force guide rod; 36. Elastic member; 37. Bearing seat; 38. Tensioning wheel; 39. Tension spring; 40. Adjustment box; 41. Worm; 42. Worm wheel; 43. Cam; 44. First driven gear; 45. Second active pulley; 46. Agitator; 47. Second driven pulley; 48. Second belt; 49. Guide plate. DETAILED DESCRIPTION

[0022] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the technical solutions of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0023] like Figure 1 to Figure 6As shown, a soil remediation device for heavy metal soil contamination includes a pulping tank 1, a hopper 14 for adding a leaching agent is arranged on the side wall of the pulping tank 1, a screen drum shell 2 is arranged at the upper end of the pulping tank 1, a screen drum 3 is rotatably connected inside the screen drum shell 2, screen holes 4 are arranged on the cylinder wall of the screen drum 3, a spiral conveyor belt 5 is arranged on the inner wall of the screen drum 3, a solid phase outlet 6 is arranged at the discharge end of the screen drum shell 2, and a first driving part 7 is arranged at the upper end of the feed port of the screen drum shell 2. A first driving gear 8 is provided at the output end of the first driving part 7, an outer gear ring 9 meshing with the first driving gear 8 is provided at the feed end of the screen drum 3, a spray pipe 10 connected to an external water source is provided on the inner top wall of the screen drum shell 2, the spray pipe 10 is arranged parallel to the screen drum 3, a spray head 11 with a water outlet direction facing downward is arranged on the spray pipe 10, a water pump 12 is provided on the spray pipe 10, a slurry discharge pipe 13 is provided at the lower end of the side wall of the slurry making tank 1, and a slurry discharge valve is provided on the slurry discharge pipe 13.

[0024] Preferably, the first driving unit 7 is a motor.

[0025] During specific use, soil enters the sieve cylinder 3 from the feeding end of the sieve cylinder 3, the first driving part 7 drives the first driving gear 8 to rotate, and the first driving gear 8 drives the sieve cylinder 3 to rotate through the outer gear ring 9. Under the conveying action of the spiral conveyor belt 5, the soil and the solid phase rub against each other and gradually move to the discharge end. The water pump 12 conveys water from the external water source to the spray pipe 10, and each spray head 11 sprays it into the soil to wash the soil on the surface of the large particles of solid phase. The mud formed during the washing process passes through the sieve hole 4 and falls into the pulping tank 1. The eluent is added to the pulping tank 1 through the feeding hopper 14 to mix it with the mud, so that the heavy metals in the soil are transferred to the liquid phase, and the large particles of solid phase are finally discharged from the solid phase outlet 6, so that the soil is fully eluted. Finally, the slurry discharge valve is opened to discharge the mud from the slurry discharge pipe 13.

[0026] In order to achieve the purpose of improving the separation effect of the soil on the solid phase surface, preferably, a metal chain 16 is arranged on the inner wall of the screen drum 3. The metal chain 16 rises and falls with the rotation of the screen drum 3, forming knocking and friction with the solid phase, which is conducive to the shedding of the soil on the solid phase surface and improves the separation effect of the soil on the solid phase surface.

[0027] In order to achieve the purpose of improving the separation effect of the soil on the solid phase surface, preferably, a bracket 15 is provided on the slurry making trough 1, and the bracket 15 is located at the feeding end of the screen cylinder 3. A feeding barrel 17 is provided on the bracket 15, and a feeding hopper 21 is provided on the feeding barrel 17. The internal rotation of the feeding barrel 17 is connected with a screw conveyor 20, one end of the feeding barrel 17 extends into the interior of the screen cylinder 3, and a mounting plate 18 is provided at the other end of the feeding barrel 17. A second driving part 19 is provided on the mounting plate 18, and an output end of the second driving part 19 is fixedly connected to the screw conveyor 20. The second driving part 19 is preferably a motor. When feeding, the soil is poured into the feeding hopper 21, and the second driving part 19 drives the screw conveyor 20 to rotate, so as to evenly transport the soil in the feeding hopper 21 to the interior of the screen cylinder 3, which is beneficial to fully spraying the solid phase, facilitating the shedding of the soil on the solid phase surface, and improving the separation effect of the soil on the solid phase surface.

[0028] In order to achieve the purpose of improving the separation effect of the solid surface soil, preferably, the output end of the second driving part 19 is provided with a second driving gear 22, and the outer wall of the feed hopper 21 is rotatably connected with a second driven gear 28 meshing with the second driving gear 22, and the second driven gear 28 is coaxially provided with a driving bevel gear 29, and the inside of the feed hopper 21 is rotatably connected with a first extrusion roller 23 and a second extrusion roller 24, the first extrusion roller 23 is coaxially provided with a first driving pulley 25, and the second extrusion roller 24 is coaxially provided with a first driven pulley 26, and the first driving pulley 25 and the first driven pulley 26 are cross-drivenly connected with a first belt 27, and the first driving pulley 25 is coaxially provided with a driving bevel gear 29 meshing with the driving pulley. The driven bevel gear 30 is engaged, when feeding, the second driving part 19 drives the second driving gear 22 to rotate, the second driving gear 22 drives the driving bevel gear 29 to rotate through the second driven gear 28, the driving bevel gear 29 drives the first driving pulley 25 to rotate through the driven bevel gear 30, the first driving pulley 25 drives the first driven pulley 26 to rotate through the first belt 27, and the first driving pulley 25 and the first driven pulley 26 rotate in opposite directions, the first driving pulley 25 and the first driven pulley 26 drive the first squeezing roller 23 and the second squeezing roller 24 to rotate in opposite directions, and the falling soil blocks are broken, which is beneficial to expose the solid phase wrapped in the soil blocks, and further improves the separation effect of the soil on the solid surface.

[0029] In order to achieve the purpose of improving the separation effect of the soil on the solid surface, preferably, two slide grooves 31 are opened on the two opposite side walls of the feed hopper 21, and two sliders 32 are slidably connected inside the two slide grooves 31. The second extrusion roller 24 is rotatably connected between the two sliders 32, and a "U"-shaped connecting rod 33 is arranged between the two sliders 32. A fixed cylinder 34 is arranged on the side wall of the feed hopper 21, and a "T"-shaped guide rod 35 with one end fixedly connected to the "U"-shaped connecting rod 33 is slidably connected inside the fixed cylinder 34. An elastic member 36 is arranged between the "T"-shaped guide rod 35 and the inner side wall of the fixed cylinder 34. A belt tensioning mechanism is also arranged on the outer side wall of the feed hopper 21, and the belt tensioning mechanism includes a bearing seat 37, a tensioning wheel 38 and a tension spring 39. The bearing seat 37 is vertically slidably connected to the outer side wall of the feed hopper 21, and a tensioning wheel 38 is rotatably connected to the bearing seat 37. The first belt 27 passes around the tensioning wheel 38, and the tension spring 39 is arranged between the bearing seat 37 and the feed hopper 21.

[0030] When the soil block passes between the first squeezing roller 23 and the second squeezing roller 24, the small particles of soil will be broken. When the solid phase passes through, due to the greater hardness of the solid phase, the second squeezing roller 24 is squeezed outward, the elastic member 36 is compressed, and the tension spring 39 is stretched. After the solid phase passes, the second squeezing roller 24 and the tensioning wheel 38 are reset under the elastic potential energy of the elastic member 36 and the tension spring 39 to continue to crush the soil block, which is beneficial to expose the solid phase wrapped in the soil block and improve the separation effect of the soil on the solid phase surface, and is also beneficial to protect the first squeezing roller 23 and the second squeezing roller 24 and extend the service life of the device.

[0031] In order to achieve the purpose of improving the separation effect of the solid surface soil, preferably, an adjusting box 40 is provided at the upper end of the fixed cylinder 34, and a worm 41 penetrating the side wall of the adjusting box 40 is rotatably connected, and a worm wheel 42 connected to the worm 41 is rotatably connected inside the adjusting box 40, and a cam 43 coaxially arranged with the worm wheel 42 is rotatably connected inside the fixed cylinder 34. The "T"-shaped guide rod 35 is in close contact with the cam surface of the cam 43 under the elastic potential energy of the elastic member 36. When feeding, the size of the soil particles passing between the first squeezing roller 23 and the second squeezing roller 24 can be adjusted. When the soil clods are large, the first squeezing roller 23 can be appropriately enlarged. The gap between the first and second squeezing rollers 23 and 24 is reduced to increase the material feeding speed. When the soil lumps in the soil are small, the gap between the first and second squeezing rollers 23 and 24 can be appropriately reduced to reduce the particle size of the soil and improve the separation effect of the soil on the solid surface. The specific operation method is: rotate the worm 41, the worm 41 drives the worm wheel 42 to rotate, and the worm wheel 42 drives the cam 43 to rotate, so that different positions of the cam surface of the cam 43 contact with the "T"-shaped guide rod 35, adjust the degree to which the cam 43 squeezes the "T"-shaped guide rod 35 outward, adjust the size of the gap between the first and second squeezing rollers 23 and 24, and lock it through the self-locking effect of the worm gear.

[0032] In order to achieve the purpose of improving the heavy metal removal effect, preferably, a first driven gear 44 meshing with the outer gear ring 9 is rotatably connected to the side wall of the slurry making tank 1, and a second driving pulley 45 is coaxially arranged on the first driven gear 44. The interior of the slurry making tank 1 is rotatably connected to a stirring paddle 46, and a second driven pulley 47 is coaxially arranged on the stirring paddle 46. A second belt 48 is connected between the second driving pulley 45 and the second driven pulley 47. The rotation of the outer gear ring 9 will drive the first driven gear 44 to rotate, the first driven gear 44 drives the second driving pulley 45 to rotate, the second driving pulley 45 drives the second driven pulley 47 to rotate through the second belt 48, and the second driven pulley 47 drives the stirring paddle 46 to rotate to stir the mud, so that the mud and the eluent are fully mixed, which is beneficial to improving the heavy metal removal effect in the soil.

[0033] Preferably, a guide plate 49 is provided inside the feed hopper 21 , and the guide plate 49 has a guiding effect on the soil, so that the soil passes between the first squeezing roller 23 and the second squeezing roller 24 .

[0034] Compared with the prior art, the present invention is provided with a slurry making tank 1, a feeding hopper 14, a screen drum shell 2, a screen drum 3, a sieve hole 4, a spiral conveyor belt 5, a solid phase outlet 6, a first driving part 7, a first driving gear 8, an outer gear ring 9, a spray pipe 10, a spray head 11, a water pump 12, a slurry outlet pipe 13 and a slurry outlet valve. Soil enters the screen drum 3 from the feeding end of the screen drum 3, the first driving part 7 drives the first driving gear 8 to rotate, and the first driving gear 8 drives the screen drum 3 to rotate through the outer gear ring 9. Under the conveying action of the spiral conveyor belt 5, the soil The soil gradually moves toward the discharge end, and the water pump 12 transports water from the external water source to the spray pipe 10, and each spray head 11 sprays it into the soil to wash the soil on the surface of the large solid particles. The mud formed during the washing process passes through the sieve hole 4 and falls into the pulping tank 1. The eluent is added to the pulping tank 1 through the feeding hopper 14 to mix it with the mud, so that the heavy metals in the soil are transferred to the liquid phase, and the large solid particles are finally discharged from the solid phase outlet 6, so that the soil is fully eluted to avoid the large solid particles returning to nature and causing secondary pollution.

[0035] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A soil remediation device for heavy metal contaminated soil, comprising a slurry making tank (1), characterized in that: A hopper (14) for adding a washing agent is arranged on the side wall of the pulping tank (1), a screen drum shell (2) is arranged on the upper end of the pulping tank (1), a screen drum (3) is rotatably connected to the interior of the screen drum shell (2), screen holes (4) are arranged on the cylinder wall of the screen drum (3), a spiral conveyor belt (5) is arranged on the inner wall of the screen drum (3), a solid phase outlet (6) is arranged at the discharge end of the screen drum shell (2), a first driving part (7) is arranged on the upper end of the feed inlet of the screen drum shell (2), and the output end of the first driving part (7) is provided with a A first driving gear (8) is arranged, an outer gear ring (9) meshing with the first driving gear (8) is arranged at the feed end of the screen drum (3), a spray pipe (10) connected to an external water source is arranged on the inner top wall of the screen drum shell (2), the spray pipe (10) is arranged parallel to the screen drum (3), a spray head (11) with a water outlet direction facing downward is arranged on the spray pipe (10), a water pump (12) is arranged on the spray pipe (10), and a pulp outlet pipe (13) is arranged at the lower end of the side wall of the pulp making tank (1), and a pulp outlet valve is arranged on the pulp outlet pipe (13).

2. The soil remediation equipment for heavy metal soil contamination according to claim 1 is characterized in that: A metal chain (16) is arranged on the inner wall of the screen cylinder (3).

3. The soil remediation equipment for heavy metal soil contamination according to claim 1 or 2, characterized in that: The pulping trough (1) is provided with a bracket (15), the bracket (15) is located at the feeding end of the screen drum (3), the bracket (15) is provided with a feeding drum (17), the feeding drum (17) is provided with a feeding hopper (21), the inside of the feeding drum (17) is rotatably connected to a screw conveyor (20), one end of the feeding drum (17) extends into the inside of the screen drum (3), the other end of the feeding drum (17) is provided with a mounting plate (18), a second driving part (19) is provided on the mounting plate (18), and the output end of the second driving part (19) is fixedly connected to the screw conveyor (20).

4. The soil remediation equipment for heavy metal soil contamination according to claim 3 is characterized by: The output end of the second driving part (19) is provided with a second driving gear (22); the outer wall of the feed hopper (21) is rotatably connected with a second driven gear (28) meshing with the second driving gear (22); the second driven gear (28) is coaxially provided with a driving bevel gear (29); the interior of the feed hopper (21) is rotatably connected with a first extrusion roller (23) and a second extrusion roller (24); the first extrusion roller (23) is coaxially provided with a first driving pulley (25); the second extrusion roller (24) is coaxially provided with a first driven pulley (26); a first belt (27) is cross-drivenly connected between the first driving pulley (25) and the first driven pulley (26); the first driving pulley (25) is coaxially provided with a driven bevel gear (30) meshing with the driving bevel gear (29).

5. The soil remediation equipment for heavy metal soil contamination according to claim 4 is characterized by: Two slide grooves (31) are provided on two opposite side walls of the feed hopper (21), and two sliders (32) are slidably connected inside the two slide grooves (31). The second extrusion roller (24) is rotatably connected between the two sliders (32), and a "U"-shaped connecting rod (33) is arranged between the two sliders (32). A fixed cylinder (34) is arranged on the side wall of the feed hopper (21), and a "T"-shaped guide rod (35) with one end fixedly connected to the "U"-shaped connecting rod (33) is slidably connected inside the fixed cylinder (34). An elastic member (36) is arranged between the "T"-shaped guide rod (35) and the inner side wall of the fixed cylinder (34). A belt tensioning mechanism is also arranged on the outer side wall of the feed hopper (21).

6. The soil remediation equipment for heavy metal soil contamination according to claim 5 is characterized by: The belt tensioning mechanism comprises a bearing seat (37), a tensioning wheel (38) and a tension spring (39); the bearing seat (37) is vertically slidably connected to the outer wall of the feed hopper (21); the bearing seat (37) is rotatably connected to the tensioning wheel (38); the first belt (27) passes around the tensioning wheel (38); and the tension spring (39) is arranged between the bearing seat (37) and the feed hopper (21).

7. The soil remediation equipment for heavy metal soil contamination according to claim 6 is characterized by: An adjusting box (40) is arranged at the upper end of the fixed cylinder (34), and a worm (41) penetrating through the side wall of the adjusting box (40) is rotatably connected thereto; a worm wheel (42) drivingly connected to the worm (41) is rotatably connected inside the adjusting box (40); a cam (43) coaxially arranged with the worm wheel (42) is rotatably connected inside the fixed cylinder (34); and the "T"-shaped force guide rod (35) is in close contact with the cam surface of the cam (43) under the action of the elastic potential energy of the elastic member (36).

8. The soil remediation equipment for heavy metal soil contamination according to claim 1 is characterized by: A first driven gear (44) meshing with an outer gear ring (9) is rotatably connected to the side wall of the pulp making trough (1); a second driving pulley (45) is coaxially arranged on the first driven gear (44); a stirring paddle (46) is rotatably connected inside the pulp making trough (1); a second driven pulley (47) is coaxially arranged on the stirring paddle (46); a second belt (48) is transmission-connected between the second driving pulley (45) and the second driven pulley (47).

Images