Heavy metal contaminated soil layered treatment device and treatment method

Abstract

The invention relates to the technical field of contaminated soil treatment, and discloses a heavy metal contaminated soil layered treatment device and method, a soil collection mechanism is rotatably arranged at the front end of a moving mechanism, and a soil treatment mechanism is arranged on the moving mechanism; the soil collecting mechanism is used for collecting polluted soil at different depths in a polluted area, and when the soil collecting mechanism rotates from the first position to the second position, the soil collecting mechanism sends the polluted soil into the soil treatment mechanism. Dividing the pollution area into multiple layers of pollution units from top to bottom according to the pollution degree, determining the depth of each layer of pollution unit, and treating the polluted soil in different pollution units in sequence; soil treatment adopts a combined mode of chemical remediation and electrokinetic remediation, the type and dosage of fed chemical agents and the power of an electric field are determined according to the content of heavy metal and organic pollutants in the contaminated soil, targeted treatment parameters can be set according to the pollution conditions of different pollution units, and the method is suitable for layered treatment of the heavy metal contaminated soil.

Description

Technical Field

[0001] This invention relates to the field of soil remediation technology, and in particular to a stratified remediation device and method for heavy metal contaminated soil. Background Technology

[0002] Heavy metal soil pollution is one of the soil environmental problems, characterized by three major features: "hidden sources, long-term accumulation, and irreversible harm". It not only weakens soil productivity, but also threatens food security and human health through the food chain.

[0003] Current technologies typically utilize physical and chemical methods to remediate soil, restoring heavy metal content to normal levels. Chemical methods are currently the most commonly used, involving spraying chemical agents onto heavy metal-contaminated soil and utilizing the reaction between the chemicals and the heavy metal pollutants to reduce their concentration. However, existing chemical soil remediation methods have the following technical drawbacks:

[0004] 1. In the actual operation of chemical soil remediation, chemical agents are usually sprayed onto contaminated soil. The soil remediation agents react with the pollutants to achieve the purpose of soil remediation. However, the sprayed chemical agents tend to remain on the surface of the soil (especially solid particles) and have difficulty penetrating into the deeper soil layers. Often, it is necessary to use engineering vehicles to plow the land or use mixing devices to mix the soil so that it can react with the deeper soil layers. However, it is still impossible to guarantee the uniformity of the mixing between the chemical agents and the contaminated soil, which affects the soil remediation effect.

[0005] 2. Heavy metal contaminated soils often exhibit stratification, meaning that the degree of contamination varies at different depths, requiring different dosages of chemicals for chemical remediation. Excessive application of sprayed chemicals can leave residues and cause secondary soil pollution, while insufficient application can negatively impact remediation effectiveness. Current methods of spraying chemical agents cannot target the specific dosages needed for different layers of contaminated soil.

[0006] 3. Soil remediation processes rely entirely on the reaction rate between chemical agents and pollutants, resulting in low remediation efficiency.

[0007] In view of this, how to provide a method for remediating heavy metal contaminated soil that can partially or completely solve the above-mentioned technical defects is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a stratified treatment device and method for heavy metal contaminated soil, so as to solve the problems existing in the prior art.

[0009] To achieve the above objectives, the present invention provides a stratified remediation device for heavy metal contaminated soil, comprising:

[0010] Mobile mechanism;

[0011] A soil collection mechanism is rotatably mounted at the front end of the moving mechanism;

[0012] A soil treatment mechanism is mounted on the moving mechanism; the soil collection mechanism is used to collect contaminated soil at different depths in the contaminated area. When the soil collection mechanism rotates from the first position to the second position, the soil collection mechanism sends the contaminated soil into the soil treatment mechanism.

[0013] Furthermore, the soil sampling device includes:

[0014] The excavating plate has one end hinged to the front end of the moving mechanism and the other end tilted downwards. When the excavating plate rotates from the second position to the first position, the excavating plate can be inserted into the contaminated area. When the moving mechanism moves and the excavating plate is inserted into the contaminated area, the excavating plate can excavate and collect contaminated soil.

[0015] The first side baffle is vertically installed on both sides of the excavation plate;

[0016] A telescopic cylinder is provided on the moving mechanism, and the telescopic cylinder is hinged to the inner wall of the housing. The telescopic rod of the telescopic cylinder is hinged to the first side baffle. When the telescopic rod extends or retracts, the digging plate and the first side baffle rotate between a first position and a second position.

[0017] Furthermore, it also includes:

[0018] A ramp is provided on the moving mechanism. One end of the ramp is connected to the excavating plate through a first rubber plate, and the other end of the ramp is inclined downward and corresponds to the soil treatment mechanism.

[0019] The second side baffle is vertically installed on both sides of the slope. One end of the second side baffle is connected to the first side baffle through a second rubber plate. The two second side baffles and the other end of the slope form a discharge port, allowing contaminated soil to slide from the excavation plate into the slope and be sent to the soil treatment mechanism through the discharge port.

[0020] Furthermore, the soil treatment facility includes:

[0021] A ring-shaped mobile platform is mounted on the mobile mechanism;

[0022] Multiple soil treatment boxes are set on the annular moving platform. The annular moving platform is used to move the multiple soil treatment boxes sequentially to the position corresponding to the discharge port and to receive contaminated soil at different depths in the contaminated area.

[0023] A chemical agent dispensing mechanism is located on the top surface of the housing. The soil treatment tank has an upper opening, and the chemical agent dispensing mechanism is used to dispense chemical agents into the soil treatment tank.

[0024] Furthermore, the chemical agent dispensing mechanism is provided in multiple ways, and each of the multiple chemical agent dispensing mechanisms stores and dispenses different chemical agents.

[0025] Furthermore, it also includes:

[0026] Multiple vibration platforms are set on the annular moving platform and are positioned one by one at the bottom of the soil treatment box.

[0027] Furthermore, it also includes:

[0028] The electric remediation mechanism is installed inside the soil treatment tank and can generate an electric field inside the soil treatment tank. Heavy metal ions in the contaminated soil react with chemical agents to generate heavy metal compounds. The heavy metal compounds accumulate around the electric remediation mechanism and form a heavy metal enrichment solution.

[0029] Furthermore, the electric repair mechanism includes:

[0030] A cathode plate is disposed on one side of the soil treatment box;

[0031] An anode plate is disposed on the other side of the soil treatment box. An electric field is formed between the cathode plate and the anode plate, and heavy metal compounds are enriched around the cathode plate or the anode plate to form a heavy metal enrichment solution.

[0032] An electrical connector is located at the edge of the opening on the soil treatment box, and the electrical connector is electrically connected to the anode plate and the cathode plate respectively.

[0033] Furthermore, the soil treatment box includes:

[0034] A partition is horizontally installed inside the soil treatment tank, and a solution storage cavity is formed between the partition and the bottom surface of the soil treatment tank;

[0035] A support block is disposed on the partition plate, and the support block is spaced apart from the inner side wall of the soil treatment box to form an installation chamber;

[0036] A permeation block is disposed in the mounting chamber and flush with the upper surface of the support block, and the permeation block is in communication with the solution storage chamber;

[0037] The cathode plate and anode plate are respectively disposed on the permeation block, and the cavity between the cathode plate and the anode plate is used to receive the contaminated soil;

[0038] The drain pipe has one end connected to the solution storage chamber and the other end extending to the outside, and a drain valve is provided on the drain pipe.

[0039] This invention also discloses a method for stratified remediation of heavy metal contaminated soil, which utilizes a stratified remediation device for heavy metal contaminated soil and includes the following steps:

[0040] S1: Based on the degree of pollution in the polluted area, the polluted area is divided into multiple pollution units from top to bottom, and the depth of each pollution unit is determined. The degree of pollution is determined based on the content of heavy metals and organic pollutants in the polluted area.

[0041] S2: The excavator plate is moved from the second position to the first position by the telescopic cylinder. During the movement, the excavator plate is inserted into the contaminated area, and the insertion depth corresponds to the depth of the uppermost contaminated unit. The first rubber plate and the second rubber plate are stretched. The moving mechanism starts to move, and the contaminated soil is excavated and collected by the excavator plate. The excavator plate is moved from the first position to the second position by the telescopic cylinder. During the movement, the excavator plate is removed from the contaminated area, and the first rubber plate and the second rubber plate are restored. The excavator plate gradually tilts upward, and the contaminated soil slides along the excavator plate to the slope and slides along the slope to the discharge port.

[0042] S3: The circular mobile platform moves a soil treatment box to a position corresponding to the discharge port and catches the contaminated soil falling from the discharge port;

[0043] S4: The soil treatment box that receives contaminated soil is moved towards the chemical agent dispensing mechanism by the ring-shaped moving platform. During the movement, the vibrating platform vibrates the soil treatment box to make the contaminated soil spread evenly inside the soil treatment box.

[0044] S5: Chemical Remediation: When the soil treatment tank moves directly below the chemical agent dispensing mechanism, the circular moving platform stops moving, and the chemical agent dispensing mechanism dispenses chemical agents into the soil treatment tank. The type and dosage of the chemical agents dispensed are determined based on the content of heavy metals and organic pollutants in the contaminated soil. The vibrating platform continues to vibrate, mixing the contaminated soil and chemical agents evenly to form heavy metal compounds.

[0045] S6: Electric Remediation: Remove the soil treatment box from the vibration platform, connect the power plug, and an electric field is formed inside the soil treatment box by the cathode and anode plates. The power of the electric field is determined based on the content of heavy metals and organic pollutants in the contaminated soil. Under the action of the electric field, heavy metal compounds accumulate around the cathode or anode plates to form a heavy metal enrichment solution. The heavy metal enrichment solution flows downward and is collected in the solution storage chamber through the permeation block. When the heavy metal enrichment solution in the solution storage chamber no longer increases, open the drain valve to drain the heavy metal enrichment solution.

[0046] S7: Repeat steps S2-S6 to treat the contaminated soil corresponding to the multi-layered contaminated units in the contaminated area from top to bottom. After treatment, the contaminated soil is converted into backfill soil.

[0047] S8: Backfill the treated soil into the contaminated area in a bottom-up order, and cover the surface of the top layer of soil with a green plant layer.

[0048] The present invention discloses the following technical effects:

[0049] 1. Based on the degree of pollution, the polluted area is divided into multiple pollution units from top to bottom. The depth of each pollution unit is determined, and polluted soil from different pollution units is collected and treated sequentially. Soil treatment adopts a combination of chemical remediation and electroremediation. The type and dosage of chemical agents and the power of the electric field are determined according to the content of heavy metals and organic pollutants in the polluted soil. Targeted treatment parameters can be set for the pollution status of different pollution units. This method is suitable for the treatment of stratified heavy metal polluted soil, improving treatment effect and efficiency, and saving treatment energy consumption and costs.

[0050] 2. After the contaminated soil enters the soil treatment tank, the vibrating platform vibrates continuously, which can spread the contaminated soil evenly in the soil treatment tank and mix the contaminated soil with chemical agents evenly, thereby improving the chemical remediation effect. In addition, after the contaminated soil is treated in layers, the depth of the single contaminated unit is greatly reduced, which can avoid the problem that deep soil cannot be effectively treated.

[0051] 3. During the electro-remediation process, the heavy metal enrichment solution is collected in real time into the solution storage chamber through the permeation block. This can prevent the heavy metal enrichment solution from flowing back into the soil and can also accelerate the enrichment speed of heavy metal compounds to the cathode and anode plates, thereby improving the effect and efficiency of electro-remediation and thus improving the overall quality of soil treatment. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is a schematic diagram of the structure of the present invention;

[0054] Figure 2 This is a schematic diagram of the telescopic cylinder connection;

[0055] Figure 3 This is a schematic diagram of the internal structure of the shell;

[0056] Figure 4 This is a top view of the ring-shaped mobile platform.

[0057] Figure 5 This is a schematic diagram of the soil treatment box structure;

[0058] The components include: 1. Moving mechanism; 2. Excavating plate; 3. First side baffle; 4. Telescopic cylinder; 5. First hinge shaft; 6. First limiting component; 7. Second hinge shaft; 8. Second limiting component; 9. Slope; 10. Second side baffle; 11. Discharge port; 12. First rubber plate; 13. Second rubber plate; 14. Circular moving platform; 15. Soil treatment box; 16. Chemical agent dispensing mechanism; 17. Vibrating platform; 18. Cathode plate; 19. Anode plate; 20. Power connector; 21. Partition; 22. Solution storage chamber; 23. Support block; 24. Permeation block; 25. Drain pipe; 26. Shell. Detailed Implementation

[0059] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0061] like Figures 1 to 5 As shown, an embodiment of the present invention provides a stratified remediation device for heavy metal contaminated soil, comprising:

[0062] The mobile mechanism 1 has a corresponding drive mechanism and can move along the contaminated area. A housing 26 is provided above the mobile mechanism 1. The housing 26 is similar to the cargo box of a truck and has sufficient height and defines sufficient internal space.

[0063] A soil collection mechanism is rotatably mounted at the front end of the moving mechanism 1;

[0064] The soil treatment mechanism is mounted on the mobile mechanism 1; the soil collection mechanism is used to collect contaminated soil at different depths in the contaminated area. When the soil collection mechanism rotates from the first position to the second position, the soil collection mechanism sends the contaminated soil into the soil treatment mechanism.

[0065] In this embodiment, the soil sampling device includes:

[0066] The excavating plate 2 has one end hinged to the front end of the moving mechanism 1 (the specific hinge structure can use an existing structure, which will not be described in detail here). The hinge position is close to the bottom of the housing 26, and the other end is tilted downwards. When the excavating plate 2 rotates from the second position to the first position, the excavating plate 2 can be inserted into the contaminated area. When the moving mechanism 1 moves and the excavating plate 2 is inserted into the contaminated area, the excavating plate 2 can excavate and collect contaminated soil. It should be noted that when the excavating plate 2 rotates to the second position, the excavating plate 2 tilts upwards, and the excavated contaminated soil can slide along the excavating plate 2 by gravity. When the excavating plate 2 rotates to the first position, the excavating plate 2 can be inserted into the contaminated area more deeply. In fact, before the excavating plate 2 reaches the first position, the excavating plate 2 has already entered below the surface of the contaminated area. Therefore, the depth of the excavating plate 2 inserted into the contaminated area can be adjusted by rotating the excavating plate 2, so as to realize the excavation and collection of contaminated soil at different depths.

[0067] The first side baffle 3 is vertically installed on both sides of the excavation plate 2. The first side baffle 3 is used to prevent the contaminated soil collected during excavation from overflowing from both sides.

[0068] The telescopic cylinder 4 and the moving mechanism 1 are provided with a housing 26. The telescopic cylinder 4 is hinged to the inner wall of the housing 26. The telescopic rod of the telescopic cylinder 4 is hinged to the first side baffle 3. When the telescopic rod extends or retracts, the digging plate 2 and the first side baffle 3 rotate between the first position and the second position.

[0069] In this embodiment, the telescopic cylinder 4 is hinged to the inner wall of the housing 26 via a first hinge shaft 5. A first limiting member 6 is provided on the first hinge shaft 5 to prevent the telescopic cylinder 4 from separating from the first hinge shaft 5. Similarly, the telescopic rod is hinged to the inner wall of the first side baffle 3 via a second hinge shaft 7. A second limiting member 8 is provided on the second hinge shaft 7 to prevent the telescopic rod from separating from the second hinge shaft 7.

[0070] In this embodiment, it also includes:

[0071] The ramp 9 is set on the moving mechanism 1. One end of the ramp 9 is connected to the excavation plate 2 through the first rubber plate 12, and the other end of the ramp 9 is inclined downward and corresponds to the soil treatment mechanism.

[0072] The second side baffle 10 is vertically installed on both sides of the slope 9. One end of the second side baffle 10 is connected to the first side baffle 3 through the second rubber plate 13. The two second side baffles 10 and the other end of the slope 9 form a discharge port 11, through which the contaminated soil can slide from the excavation plate 2 into the slope 9 and be sent to the soil treatment mechanism through the discharge port 11.

[0073] Since the excavator plate 2 and the first side baffle 3 need to rotate, sufficient rotation clearance must be maintained between the excavator plate 2 and the slope 9, and between the first side baffle 3 and the second side baffle 10. However, this clearance can lead to contaminated soil leakage. To avoid this situation, in this embodiment, a first rubber plate 12 is provided between the excavator plate 2 and the slope 9, and a second rubber plate 13 is provided between the first side baffle 3 and the second side baffle 10. When the excavator plate 2 and the first side baffle 3 rotate between the first position and the second position, the first rubber plate 12 and the second rubber plate 13 can maintain the connection between the excavator plate 2 and the slope 9 and the connection between the first side baffle 3 and the second side baffle 10 through tensile deformation, thus preventing soil leakage.

[0074] In some other embodiments, the first rubber plate 12 and the second rubber plate 13 may also be of slightly larger size, so that they are bent downwards in the normal state, and when the excavator plate 2 is rotated to the second position, the first rubber plate 12 and the second rubber plate 13 are straightened to avoid the rubber plates from being overstretched and breaking.

[0075] In this embodiment, the soil treatment mechanism includes:

[0076] A ring-shaped mobile platform 14 is mounted on the mobile mechanism 1. The ring-shaped mobile platform 14 is shaped like a 400m running track. It has multiple workstations on top for placing soil treatment boxes 15. The ring-shaped mobile platform 14 has a corresponding ring-shaped mobile drive mechanism. Its bottom is fixed on the mobile mechanism 1, and its top is movable relative to the bottom.

[0077] Multiple soil treatment boxes 15 are set on a ring-shaped mobile platform 14. The soil treatment boxes 15 can be detachably connected to the ring-shaped mobile platform 14 by means of snap-fit ​​or other means, which facilitates later loading and unloading. The ring-shaped mobile platform 14 is used to move multiple soil treatment boxes 15 sequentially to the position corresponding to the discharge port 11 and to receive contaminated soil of different depths in the contaminated area.

[0078] A chemical agent dispensing mechanism 16 is located on the top surface of the housing 26. The soil treatment tank 15 has an upper opening. The chemical agent dispensing mechanism 16 is used to dispense chemical agents into the soil treatment tank 15.

[0079] In this embodiment, multiple chemical agent dispensing mechanisms 16 are provided, each storing and dispensing different chemical agents. Heavy metal pollutants include Cd, Pb, Cu, Zn, Ni, Cr, etc.; chemical agents can be HCl (pH≈3), FeCl3, Fe(NO3)3, etc. The number of chemical agent dispensing mechanisms 16 and the types of chemical agents dispensed can be flexibly adjusted according to actual needs.

[0080] In this embodiment, it also includes:

[0081] Multiple vibration platforms 17 are mounted on the annular moving platform 14 and are positioned one-to-one at the bottom of the soil treatment box 15. The vibration direction of the vibration platform 17 should be the same as the length direction of the soil treatment box 15, which can improve the leveling effect of the contaminated soil and the mixing effect of the contaminated soil and chemical agents.

[0082] In this embodiment, it also includes:

[0083] The electric remediation mechanism is installed inside the soil treatment tank 15 and can generate an electric field inside the soil treatment tank 15. Heavy metal ions in the contaminated soil react with chemical agents to generate heavy metal compounds. The heavy metal compounds accumulate around the electric remediation mechanism and form a heavy metal enrichment solution.

[0084] In this embodiment, the electric repair mechanism includes:

[0085] A cathode plate 18 is disposed on one side of the soil treatment box 15;

[0086] An anode plate 19 is disposed on the other side of the soil treatment box 15. An electric field is formed between the cathode plate 18 and the anode plate 19. Heavy metal compounds are enriched around the cathode plate 18 or the anode plate 19 and form a heavy metal enrichment solution.

[0087] The power connector 20 is located at the edge of the opening on the soil treatment box 15, and the power connector 20 is electrically connected to the anode plate 19 and the cathode plate 18 respectively.

[0088] In this embodiment, the soil treatment box 15 includes:

[0089] A partition 21 is horizontally installed inside the soil treatment box 15, and a solution storage cavity 22 is formed between the partition 21 and the bottom surface of the soil treatment box 15.

[0090] Support block 23 is set on partition plate 21. Support block 23 is spaced apart from the inner side wall of soil treatment box 15 to form an installation chamber.

[0091] The permeation block 24 is set in the installation chamber and is flush with the upper surface of the support block 23. The permeation block 24 is connected to the solution storage chamber 22. The partition 21 below the permeation block 24 can be opened with permeation holes or grooves to facilitate the heavy metal enrichment solution to pass through the permeation block 24 and enter the solution storage chamber 22.

[0092] The cathode plate 18 and the anode plate 19 are respectively disposed on the permeation block 24, and the cavity between the cathode plate 18 and the anode plate 19 is used to receive contaminated soil.

[0093] The drain pipe 25 is connected at one end to the solution storage chamber 22 and extends to the outside at the other end. A drain valve is provided on the drain pipe 25.

[0094] In some other embodiments, a level gauge may be installed in the solution storage chamber 22 to monitor the liquid level in the solution storage chamber 22 and determine the node where liquid needs to be drained.

[0095] In other embodiments, a control center may be set up to intelligently control the entire device, such as controlling the speed and distance of the circular moving platform 14, and controlling the amount of chemical agent dispensed by the chemical agent dispensing mechanism 16.

[0096] This invention also discloses a method for stratified remediation of heavy metal contaminated soil, which utilizes a stratified remediation device for heavy metal contaminated soil and includes the following steps:

[0097] S1: Based on the degree of pollution in the polluted area, the polluted area is divided into multiple pollution units from top to bottom, and the depth of each pollution unit is determined. The degree of pollution is determined based on the content of heavy metals and organic pollutants in the polluted area.

[0098] S2: The excavating plate 2 is moved from the second position to the first position by the telescopic cylinder 4. During the movement, the excavating plate 2 is inserted into the contaminated area, and the insertion depth corresponds to the depth of the uppermost contaminated unit. The first rubber plate 12 and the second rubber plate 13 are stretched. The moving mechanism 1 starts to move, and the contaminated soil is excavated and collected by the excavating plate 2. The excavating plate 2 is moved from the first position to the second position by the telescopic cylinder 4. During the movement, the excavating plate 2 is removed from the contaminated area, and the first rubber plate 12 and the second rubber plate 13 are restored. The excavating plate 2 gradually tilts upward, and the contaminated soil slides along the excavating plate 2 to the slope 9 and slides along the slope to the discharge port 11.

[0099] S3: The circular mobile platform 14 moves a soil treatment box 15 to a position corresponding to the discharge port 11 and receives the contaminated soil falling from the discharge port 11;

[0100] S4: The soil treatment box 15, which receives contaminated soil, is moved by the ring-shaped moving platform 14 to the chemical agent dispensing mechanism 16. During the movement, the vibration platform 17 vibrates the soil treatment box 15 so that the contaminated soil is evenly spread inside the soil treatment box 15.

[0101] S5: Chemical remediation: When the soil treatment tank 15 moves directly below the chemical agent dispensing mechanism 16, the annular moving platform 14 stops moving, and the chemical agent dispensing mechanism 16 dispenses chemical agents into the soil treatment tank 15. The type and dosage of the chemical agents dispensed are determined based on the content of heavy metals and organic pollutants in the contaminated soil. The vibrating platform 17 vibrates continuously to mix the contaminated soil and chemical agents evenly to form heavy metal compounds.

[0102] S6: Electric remediation: Remove the soil treatment box 15 from the vibration platform 17, energize the power plug 20, and form an electric field in the soil treatment box 15 with the cathode plate 18 and the anode plate 19. The power of the electric field is determined according to the content of heavy metals and organic pollutants in the contaminated soil. Under the action of the electric field, heavy metal compounds accumulate around the cathode plate 18 or the anode plate 19 to form a heavy metal enrichment solution. The heavy metal enrichment solution flows downward and is collected in the solution storage chamber 22 through the permeation block 24. When the heavy metal enrichment solution in the solution storage chamber 22 no longer increases, open the drain valve to discharge the heavy metal enrichment solution.

[0103] S7: Repeat steps S2-S6 to treat the contaminated soil corresponding to the multi-layered contaminated units in the contaminated area from top to bottom. After treatment, the contaminated soil is converted into backfill soil.

[0104] S8: Backfill the treated soil into the contaminated area in a bottom-up order, and cover the surface of the top layer of soil with a green plant layer.

[0105] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0106] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A stratified remediation device for heavy metal contaminated soil, characterized in that, include: Mobile mechanism (1); A soil collection mechanism is rotatably mounted at the front end of the moving mechanism (1); The soil treatment mechanism is mounted on the moving mechanism (1); the soil collection mechanism is used to collect polluted soil at different depths in the polluted area. When the soil collection mechanism rotates from the first position to the second position, the soil collection mechanism sends the polluted soil into the soil treatment mechanism.

2. The heavy metal contaminated soil stratification remediation device according to claim 1, characterized in that, The soil collection facility includes: The excavating plate (2) has one end hinged to the front end of the moving mechanism (1) and the other end tilted downward. When the excavating plate (2) rotates from the second position to the first position, the excavating plate (2) can be inserted into the polluted area. When the moving mechanism (1) moves and the excavating plate (2) is inserted into the polluted area, the excavating plate (2) can excavate and collect polluted soil. The first side baffle (3) is vertically installed on both sides of the excavation plate (2); Telescopic cylinder (4), the moving mechanism (1) is provided with a housing (26), the telescopic cylinder (4) is hinged to the inner wall of the housing (26), the telescopic rod of the telescopic cylinder (4) is hinged to the first side baffle (3), when the telescopic rod is extended or shortened, the digging plate (2) and the first side baffle (3) rotate between the first position and the second position.

3. The heavy metal contaminated soil stratification remediation device according to claim 2, characterized in that, Also includes: A ramp (9) is set on the moving mechanism (1). One end of the ramp (9) is connected to the excavating plate (2) through the first rubber plate (12). The other end of the ramp (9) is set downwards and corresponds to the soil treatment mechanism. The second side baffle (10) is vertically installed on both sides of the slope (9). One end of the second side baffle (10) is connected to the first side baffle (3) through the second rubber plate (13). The two second side baffles (10) and the other end of the slope (9) form a discharge port (11). The contaminated soil can slide from the excavation plate (2) into the slope (9) and be sent to the soil treatment mechanism through the discharge port (11).

4. The heavy metal contaminated soil stratification remediation device according to claim 3, characterized in that, The soil treatment facility includes: A ring-shaped mobile platform (14) is mounted on the mobile mechanism (1); Multiple soil treatment boxes (15) are set on the annular moving platform (14). The annular moving platform (14) is used to move the multiple soil treatment boxes (15) sequentially to the position corresponding to the discharge port (11) and to receive contaminated soil of different depths in the contaminated area. A chemical agent dispensing mechanism (16) is provided on the top surface of the housing (26). The soil treatment box (15) has an upper opening. The chemical agent dispensing mechanism (16) is used to dispense chemical agents into the soil treatment box (15).

5. The heavy metal contaminated soil stratification remediation device according to claim 4, characterized in that, Multiple chemical agent dispensing mechanisms (16) are provided, and each chemical agent dispensing mechanism (16) stores and dispenses different chemical agents.

6. The heavy metal contaminated soil stratification remediation device according to claim 5, characterized in that, Also includes: Multiple vibration platforms (17) are set on the annular mobile platform (14) and are respectively set at the bottom of the soil treatment box (15).

7. The heavy metal contaminated soil stratification remediation device according to claim 6, characterized in that, Also includes: The electric remediation mechanism is installed inside the soil treatment box (15) and can form an electric field inside the soil treatment box (15). Heavy metal ions in the polluted soil react with chemical agents to generate heavy metal compounds. The heavy metal compounds accumulate around the electric remediation mechanism and form a heavy metal enrichment solution.

8. The heavy metal contaminated soil stratification remediation device according to claim 7, characterized in that, The electric repair mechanism includes: A cathode plate (18) is disposed on one side of the soil treatment box (15); An anode plate (19) is disposed on the other side of the soil treatment box (15). An electric field is formed between the cathode plate (18) and the anode plate (19). Heavy metal compounds are enriched around the cathode plate (18) or the anode plate (19) and form a heavy metal enrichment solution. A power connector (20) is located at the edge of the opening on the soil treatment box (15), and the power connector (20) is electrically connected to the anode plate (19) and the cathode plate (18) respectively.

9. A stratified remediation device for heavy metal contaminated soil according to claim 8, characterized in that, The soil treatment box (15) includes: A partition (21) is horizontally disposed inside the soil treatment box (15), and a solution storage cavity (22) is formed between the partition (21) and the bottom surface of the soil treatment box (15). A support block (23) is disposed on the partition plate (21). The support block (23) is spaced apart from the inner wall of the soil treatment box (15) to form an installation chamber. A permeation block (24) is disposed in the mounting chamber and flush with the upper surface of the support block (23), and the permeation block (24) is in communication with the solution storage chamber (22); The cathode plate (18) and anode plate (19) are respectively disposed on the permeation block (24), and the cavity between the cathode plate (18) and anode plate (19) is used to receive contaminated soil; The drain pipe (25) is connected at one end to the solution storage chamber (22) and extends to the outside at the other end. A drain valve is provided on the drain pipe (25).

10. A method for stratified remediation of heavy metal contaminated soil, characterized in that, The application of the heavy metal contaminated soil stratification remediation device according to claim 9 includes the following steps: S1: Based on the degree of pollution in the polluted area, the polluted area is divided into multiple pollution units from top to bottom, and the depth of each pollution unit is determined. The degree of pollution is determined based on the content of heavy metals and organic pollutants in the polluted area. S2: The excavating plate (2) is moved from the second position to the first position by the telescopic cylinder (4). During the movement, the excavating plate (2) is inserted into the contaminated area. The insertion depth corresponds to the depth of the uppermost contaminated unit. The first rubber plate (12) and the second rubber plate (13) are stretched. The moving mechanism (1) starts to move. The contaminated soil is excavated and collected by the excavating plate (2). The excavating plate (2) is moved from the first position to the second position by the telescopic cylinder (4). During the movement, the excavating plate (2) is removed from the contaminated area. The first rubber plate (12) and the second rubber plate (13) are restored. The excavating plate (2) gradually tilts upward. The contaminated soil slides along the excavating plate (2) to the slope (9) and slides along the landslide to the discharge port (11). S3: The circular moving platform (14) moves a soil treatment box (15) to a position corresponding to the discharge port (11) and receives the contaminated soil falling from the discharge port (11); S4: The soil treatment box (15) that receives contaminated soil is moved to the chemical agent dispensing mechanism (16) by the ring moving platform (14). During the movement, the vibration platform (17) vibrates the soil treatment box (15) so that the contaminated soil is evenly spread in the soil treatment box (15). S5: Chemical remediation: When the soil treatment box (15) moves directly below the chemical agent dispensing mechanism (16), the circular moving platform (14) stops moving, and the chemical agent dispensing mechanism (16) dispenses chemical agents into the soil treatment box (15). The type and dosage of the chemical agents dispensed are determined based on the content of heavy metals and organic pollutants in the contaminated soil. The vibrating platform (17) vibrates continuously to mix the contaminated soil and chemical agents evenly to form heavy metal compounds. S6: Electric remediation: Remove the soil treatment box (15) from the vibration platform (17), turn on the power plug (20), and the cathode plate (18) and anode plate (19) form an electric field in the soil treatment box (15). The power of the electric field is determined according to the content of heavy metals and organic pollutants in the contaminated soil. Under the action of the electric field, heavy metal compounds accumulate around the cathode plate (18) or anode plate (19) to form a heavy metal enrichment solution. The heavy metal enrichment solution flows downward and is collected in the solution storage chamber (22) through the permeation block (24). When the heavy metal enrichment solution in the solution storage chamber (22) no longer increases, open the drain valve to drain the heavy metal enrichment solution. S7: Repeat steps S2-S6 to treat the contaminated soil corresponding to the multi-layered contaminated units in the contaminated area from top to bottom. After treatment, the contaminated soil is converted into backfill soil. S8: Backfill the treated soil into the contaminated area in a bottom-up order, and cover the surface of the top layer of soil with a green plant layer.

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