Equipment and method for removing heavy metals and fluoride ions in wet recycling wastewater from lithium batteries

Abstract

This invention relates to the field of industrial wastewater technology and discloses a heavy metal and fluoride ion removal device for lithium battery wet recycling wastewater treatment, comprising: a contact sedimentation device; the upper outer wall of the contact sedimentation device is connected to a contact sedimentation device inlet pipe. This invention utilizes the contact sedimentation device, taking advantage of the chelating effect and good flocculation properties of the contact material layer, to perform primary treatment of heavy metals and fluoride ions in lithium battery wet recycling wastewater, reducing the concentration of medium-level heavy metals and fluoride ions to low concentrations. Then, the wastewater passes through an adsorption filtration device, where the special pores and open framework molecular structure of the adsorption filter material layer allow it to adsorb large amounts of heavy metals and fluoride ions like a sponge. After secondary deep treatment, the concentration of heavy metals and fluoride ions meets the relevant national standards for reclaimed water reuse or discharge, exhibiting high treatment efficiency and low operating costs.

Description

Technical Field

[0001] This invention relates to the field of industrial wastewater technology, specifically to a device and method for removing heavy metals and fluoride ions in the wet recycling wastewater treatment of lithium batteries. Background Technology

[0002] With the widespread adoption of electric vehicles, smartphones, and other electronic products, the demand for lithium batteries, their core power source, has exploded. However, this has also brought about an environmental problem that cannot be ignored: the recycling and disposal of used lithium batteries.

[0003] The dismantling, crushing, and separation processes during the recycling and processing of used lithium-ion batteries generate a large amount of wastewater. This wastewater has a complex composition, containing various heavy metal ions (such as cobalt, nickel, and copper), organic matter (such as organic solvents and electrolytes), as well as pollutants such as oils and salts. The presence of these substances increases the difficulty of wastewater treatment.

[0004] In addition, the recycling of waste power lithium batteries in China still relies on wet refining. In this process, the presence of electrolyte and the limitations of the process inevitably lead to the enrichment of fluoride ions in the preparation of lithium salt compounds, resulting in excessive fluoride content and environmental pollution problems.

[0005] Currently, in China, traditional coagulation-sedimentation and adsorption methods are generally used for the wet recovery of heavy metals and fluoride ions from lithium battery wastewater. Traditional coagulation-sedimentation methods remove heavy metals and fluoride ions by adding calcium salts to form insoluble calcium fluoride precipitates, but this cannot achieve deep removal of heavy metals. Traditional adsorption methods remove heavy metals and fluoride ions by adding aluminum sulfate, but this method requires large amounts of capital, has high removal costs, and causes difficulties in sludge defiltration, which is detrimental to production.

[0006] To address this issue, we propose a device and method for removing heavy metals and fluoride ions in the wet recycling wastewater from lithium batteries. Summary of the Invention

[0007] The purpose of this invention is to provide a device and method for removing heavy metals and fluoride ions in the wet recycling wastewater treatment of lithium batteries, thereby solving the problems mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a heavy metal and fluoride ion removal device for wet lithium battery recycling wastewater treatment, comprising:

[0009] Contact sedimentation equipment;

[0010] The upper outer wall of the contact sedimentation equipment is connected to a water inlet pipe, and the interior of the contact sedimentation equipment is provided with a flow guiding zone. A support plate is provided in the lower middle part between the wall panel of the flow guiding zone and the tail tank wall. A pad layer is provided on the support plate, and a contact material layer is provided on the top surface of the pad layer. The area above the contact material layer is a clear water zone. A backflushing air pipe is provided below the support plate. A sludge hopper is provided at the bottom of the contact sedimentation equipment, and a sludge discharge pipe is provided at the bottom of the sludge hopper. The contact sedimentation equipment is also provided with a post-sedimentation clear water tank. Water passage holes are provided on the common wall of the contact sedimentation equipment and the post-sedimentation clear water tank. A submersible lift pump is provided at the bottom of the post-sedimentation clear water tank, and a lift pump outlet pipe is connected to the submersible lift pump.

[0011] Adsorption filtration equipment;

[0012] The lower part of the adsorption filtration equipment is an adsorption filtration box, and the upper part is an adsorption filtration water storage tank, which are separated by a steel partition. The upper part of the adsorption filtration box is equipped with an adsorption filtration box inlet valve, which is connected to the outlet pipe of the lift pump. The bottom plate of the adsorption filtration box and the bottom of the filter plate and filter head assembly form a backwash water and air distribution space. A support layer is provided on the top of the filter head and filter plate assembly. A backwash drain valve is provided at the end of the adsorption filtration box inlet valve. A connecting pipe valve is provided between the bottom of the adsorption filtration water storage tank and the backwash water and air distribution space at the bottom of the adsorption filtration box. The backwash water and air distribution space is equipped with a bottom drain valve and a backwash air valve.

[0013] Centrifugal fan;

[0014] The air outlet of the centrifugal fan is connected to the backflushing air pipe and the backwash air pipe valve via the air delivery pipe valve.

[0015] Preferably, both the contact sedimentation equipment and the adsorption filtration equipment adopt an integrated housing and are made of corrosion-resistant carbon steel.

[0016] Preferably, the support plate is made of corrosion-resistant steel plate, the support plate has holes with a diameter of 15mm and a hole spacing of 115mm, and the support plate is covered with nylon mesh with a mesh size of 36 mesh / inch.

[0017] Preferably, the subbase material is made of pebbles with a particle size of 1625 mm and a laying thickness of 100 mm.

[0018] Preferably, the contact material layer is a mixture of a 24mm crayfish shell obtained by processing, crushing, and sieving, and nonionic polyacrylamide and polyferric chloride, and the thickness of the contact material layer is 500mm.

[0019] Preferably, the filter plate of the filter plate and filter head assembly is made of spliced ​​steel plates, and the size of a single filter plate is 980×980 (mm). At the same time, a hole is set on a single filter plate, the diameter of the hole is 25mm and the spacing is 125×125 (mm), and an adjustable ABS long-handled filter head is installed on the hole.

[0020] Preferably, the support layer material is quartz sand with a particle size of 24 mm and a thickness of 200 mm. An adsorption filter media layer is set on top of the support layer. The adsorption filter media layer is made of processed crayfish shells, zeolite, palygorskite, etc., crushed to a particle size of less than 100 mesh, then mixed with a small amount of sodium polyacrylate and a pore-forming agent, and then mixed with 20% water and granulated to form a particle size of 12 mm. The thickness of the adsorption filter media layer is 1500 mm. A drain valve is set at the top of the adsorption filter media layer. An outlet channel and a filtered water pipe are set at the designed water level of the adsorption filter water storage tank.

[0021] In addition to the above-mentioned technical solutions, the present invention also includes:

[0022] A method for removing heavy metals and fluoride ions in the wet recycling wastewater from lithium batteries includes the following steps:

[0023] S1: Wastewater from the wet recycling of lithium batteries enters the guide zone through the inlet pipe of the contact sedimentation equipment, bypasses the guide plate, and enters the clear water zone through the support plate, pad layer, and contact material layer.

[0024] S2: The water enters the post-sedimentation clear water tank through the water passage hole set on the common wall of the contact sedimentation equipment and the post-sedimentation clear water tank;

[0025] S3: The water enters the adsorption filter box of the adsorption filtration equipment through the submersible lift pump and the lift pump outlet pipe set at the bottom of the sedimentation clear water tank and the inlet pipe valve of the adsorption filter box connected thereto.

[0026] S4: Most heavy metals and fluoride ions settle and are stored in the sludge hopper after sludge-water separation due to the chelating effect of the contact material layer and the flocculation effect of the fluoride ions. In addition, a small portion is trapped in the contact material layer. In order to avoid excessive head loss caused by the accumulation of sludge containing heavy metals and fluoride ions in the contact material layer during operation, backwashing is performed regularly using a backwash air pipe installed under the support plate. The backwashing cycle is 7 days, the backwash air intensity is 15L / (S·㎡), and the backwashing time is 23min. The backwash air source is supplied by the air outlet of the centrifugal fan through the air delivery valve and the backwash air pipe connected thereto. The sludge in the sludge hopper is discharged through the sludge discharge pipe and recycled and utilized by a qualified unit. The contact sedimentation time of the contact sedimentation equipment is 20-30min.

[0027] S5: After primary treatment by the contact material layer of the contact precipitation equipment, the concentration of heavy metals and fluoride ions in the wet recovery wastewater of lithium batteries can be reduced from medium to low.

[0028] In addition to the above-mentioned technical solutions, the present invention also includes:

[0029] A1: After the heavy metals and fluoride ions in the wet recovery wastewater of lithium batteries are removed by the contact precipitation equipment, they enter the adsorption filtration equipment for secondary deep removal through the submersible lift pump set at the bottom of the sedimentation clear water tank, the lift pump outlet pipe and the inlet pipe of the adsorption filter box connected thereto.

[0030] A2: During adsorption filtration, the treated water enters the backwash water and air distribution space through the inlet valve of the adsorption filter box, the adsorption filter media layer, the support layer, and the filter plate and filter head assembly. The adsorption filtration effluent flows upward through the connecting pipe valve into the adsorption filtration storage tank. Finally, it flows out through the outlet channel of the adsorption filtration storage tank and the connected filtered water pipe for recycling or discharge in compliance with standards.

[0031] A3: When treated water passes through the adsorption filter media layer, the special pores and open framework molecular structure inside the filter material allow it to adsorb a large amount of heavy metals and fluoride ions like a sponge and remove them. When the adsorption filtration head of the adsorption filter media layer reaches the set value, backwashing is performed. During backwashing, first close the inlet valve and connecting valve of the adsorption filter box, open the bottom drain valve for 3 minutes, drain some water from the backwash water and air distribution space, and lower the water level to 200mm on the surface of the adsorption filter media layer. Then open the top drain valve of the adsorption filter media layer to drain the water above the top drain valve of the adsorption filter media layer. Next, open the backwash air valve to perform air backwashing to loosen the adsorption filter media layer for 8 minutes. Then open the connecting valve and the backwash drain valve for 4 minutes, so that the water in the storage tank after adsorption filtration flows from bottom to top through the backwash water and air distribution space, filter plate and filter head assembly, and support layer to backwash the adsorption filter media layer.

[0032] A4: Finally, close the backwash drain valve and open the inlet valve of the adsorption filter box to restart the adsorption filtration. The backwash cycle is 48 hours. The adsorption filtration rate of the adsorption filter equipment is 2 m / h, the air flushing intensity is 1216 L / (S·㎡), and the water flushing intensity is 34 L / (S·㎡). The air source for air and water flushing is supplied by the air outlet of the centrifugal fan (3) through the backwash air valve.

[0033] A5: After secondary treatment by the adsorption filter media layer of the adsorption filtration equipment, the heavy metals and fluoride ions in the wet recovery wastewater of lithium batteries can be reduced from low concentrations to the relevant national standards for water reuse or discharge.

[0034] This invention provides an apparatus and method for removing heavy metals and fluoride ions in the wet treatment of lithium battery recycling wastewater. This apparatus and method for removing heavy metals and fluoride ions in the wet treatment of lithium battery recycling wastewater has the following beneficial effects:

[0035] This invention utilizes a contact sedimentation device, taking advantage of the chelating effect and excellent flocculation properties of the contact material layer, to perform primary treatment of heavy metals and fluoride ions in wet lithium battery recovery wastewater. This reduces the concentration of heavy metals and fluoride ions from moderate levels to low levels. The wastewater then passes through an adsorption filtration device, where the unique pores and open framework molecular structure of the adsorption filter material allow it to adsorb large amounts of heavy metals and fluoride ions like a sponge. After secondary deep treatment, the concentration of heavy metals and fluoride ions meets relevant national standards for wastewater reuse or discharge. This method features high treatment efficiency and low operating costs. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the structural flow of a device and method for removing heavy metals and fluoride ions in the wet recycling wastewater treatment of lithium batteries.

[0037] In the picture:

[0038] 1-Contact sedimentation equipment, 1-1-Contact sedimentation equipment inlet pipe, 1-2-Guiding zone, 1-3-Support plate, 1-4-Bedding layer, 1-5-Contact material layer, 1-6-Clear water zone, 1-7-Water passage hole, 1-8-Backwash air pipe, 1-9-Sludge hopper, 1-10-Sludge discharge pipe, 1-11-Clear water tank after sedimentation, 1-12-Submersible lift pump, 1-13-Lift pump outlet pipe;

[0039] 2-Adsorption filtration equipment, 2-1-Adsorption filter box, 2-2-Adsorption filtration water storage tank, 2-3-Adsorption filter box inlet valve, 2-4-Backwash water and air distribution room, 2-5-Filter plate and filter head assembly, 2-6-Support layer, 2-61-Adsorption filter media layer, 2-7-Backwash drain valve, 2-8-Connecting pipe valve, 2-9-Bottom drain valve, 2-10-Backwash air pipe valve, 2-11-Top drain valve of adsorption filter media layer, 2-12-Outlet channel of adsorption filtration water storage tank, 2-13-Filtered water pipe;

[0040] Centrifugal fan, 3-1- Air inlet and air inlet pipe, 3-2- Air outlet, 3-3- Air delivery pipe valve. Detailed Implementation

[0041] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0042] Example 1: A preferred embodiment of the heavy metal and fluoride ion removal equipment and method for wet lithium battery recycling wastewater treatment provided by the present invention. Figure 1 As shown: A heavy metal and fluoride ion removal device for wet lithium battery recycling wastewater treatment, comprising:

[0043] Contact sedimentation equipment 1 adopts an integrated housing and is made of corrosion-resistant carbon steel;

[0044] The upper outer wall of the contact sedimentation device 1 is connected to the inlet pipe 1-1. The interior of the contact sedimentation device 1 includes a flow guide zone 1-2. A support plate 1-3 is installed in the lower middle part between the wall panel of the flow guide zone 1-2 and the tail section wall. The support plate 1-3 is made of corrosion-resistant steel plate and has holes with a diameter of 15mm and a spacing of 115mm. The support plate 1-3 is covered with a nylon mesh of 36 mesh / inch. A pad 1-4 is installed on the support plate 1-3, made of pebbles with a particle size of 16-25mm and a thickness of 1mm. The top surface of the padding layer 1-4 has a contact material layer 1-5. The material of the contact material layer 1-5 is a mixture of 2-4 mm crayfish shells obtained by processing, crushing and sieving, and non-ionic polyacrylamide and polyferric chloride. The thickness of the contact material layer 1-5 is 500 mm. Specifically, the crayfish shells are pretreated and then subjected to acid soaking, water washing, alkali boiling, decolorization, reduction, water washing and drying. After being crushed and sieved to a particle size of 2-4 mm, they are thoroughly mixed with powdered non-ionic polyacrylamide NPAM and granular polyferric chloride PFS to obtain the contact material layer 1-5. The mass percentage of the contact material layer 1-5 is as follows: 90% of the crayfish shells processed to 2-4mm, 1% of nonionic polyacrylamide (NPAM), and 9% of polyferric chloride (PFS). Above the contact material layer 1-5 is the clear water zone 1-6. Below the support plate 1-3, there is a backflushing air pipe 1-8. The lower part of the contact sedimentation device 1 is equipped with a sludge hopper 1-9. The bottom of the sludge hopper 1-9 is equipped with a sludge discharge pipe 1-10. The contact sedimentation device 1 is equipped with a post-sedimentation clear water tank 1-11. The common wall of the contact sedimentation device 1 and the post-sedimentation clear water tank 1-11 is equipped with a water passage hole 1-7. The bottom of the post-sedimentation clear water tank 1-11 is equipped with a submersible lift pump 1-12. The submersible lift pump 1-12 is connected to the lift pump outlet pipe 1-13.

[0045] A method for removing heavy metals and fluoride ions in the wet recycling wastewater from lithium batteries includes the following steps:

[0046] S1: Wastewater from the wet recycling of lithium batteries enters the guide zone 1-2 through the inlet pipe 1-1 of the contact sedimentation equipment, bypasses the guide plate, and enters the clear water zone 1-6 through the support plate 1-3, padding layer 1-4, and contact material layer 1-5.

[0047] S2: The water enters the post-sedimentation clear water tank 1-11 through the water passage 1-7 set on the common wall of the contact sedimentation device 1 and the post-sedimentation clear water tank 1-11;

[0048] S3: The water enters the adsorption filter box 2-1 of the adsorption filter equipment 2 through the submersible lift pump 1-12 and the lift pump outlet pipe 1-13 set at the bottom of the sedimentation clear water tank 1-11 and the adsorption filter box inlet valve 2-3 connected thereto.

[0049] S4: Most heavy metals and fluoride ions settle and are stored in sludge hopper 1-9 after sludge-water separation due to the chelating effect of heavy metal ions and the flocculation effect of fluoride ions in the contact material layer 1-5. In addition, a small portion is trapped in the contact material layer 1-5. In order to avoid excessive head loss caused by the accumulation of sludge containing heavy metals and fluoride ions in the contact material layer 1-5 during operation, backwashing is performed regularly using the backwash air pipe 1-8 set under the support plate 1-3. The backwashing cycle is 7 days, the backwashing air intensity is 15L / S·㎡, and the backwashing time is 2-3min. The backwashing air source is supplied by the air outlet 3-2 of the centrifugal fan 3 through the air delivery valve 3-3 and the backwash air pipe 1-8 connected thereto. The sludge in the sludge hopper 1-9 is discharged by the sludge discharge pipe 1-10 and recycled and utilized by a qualified unit. The contact sedimentation time of the contact sedimentation equipment 1 is 20-30min.

[0050] S5: After primary treatment by the contact material layers 1-5 of the contact precipitation equipment 1, the concentration of heavy metals and fluoride ions in the wet recovery wastewater of lithium batteries can be reduced from medium to low.

[0051] Example 2: Based on the above implementation scheme, adsorption filtration device 2;

[0052] The lower part of the adsorption filtration device 2 is an adsorption filter box 2-1, and the upper part is an adsorption filter water storage tank 2-2, separated by a steel partition. An adsorption filter box inlet valve 2-3 is installed at the upper part of the adsorption filter box 2-1, which is connected to the outlet pipe 1-3 of the booster pump. The bottom plate of the adsorption filter box 2-1 and the area below the filter plate / filter head assembly 2-5 form a backwash water and air distribution space 2-4. The filter plates of the filter plate / filter head assembly 2-5 are made of spliced ​​steel plates, and each filter plate is a single piece. The filter plate measures 980×980mm and features perforations of 25mm diameter with a spacing of 125×125mm. Adjustable ABS long-handled filter heads are mounted on these perforations. A support layer 2-6, made of quartz sand with a particle size of 2-4mm and a thickness of 200mm, is placed on top of the filter head and filter plate assembly 2-5. An adsorption filter media layer 2-61 is then installed on top of the support layer 2-6. The material consists of processed crayfish shells, zeolite, palladium, etc., pulverized to a particle size of less than 100 mesh. A small amount of sodium polyacrylate and a pore-forming agent are added and mixed in dry powder form. Then, 20% water is added, mixed, and granulated to form a particle size of 1-2 mm. The adsorption filter media layer 2-61 is 1500 mm thick. A drain valve 2-11 is installed at the top of the adsorption filter media layer 2-61. A water storage tank 2-2 is installed at the designed water level after adsorption filtration. The specific preparation of the water outlet channel 2-12 and the filtered water pipe 2-13 involves pre-treating the crayfish shells by soaking in acid, washing with water, boiling in alkali, decolorizing, washing with water, drying, and then pulverizing them to a particle size of less than 100 mesh. Zeolite and tartar are pulverized to a particle size of less than 100 mesh. The dry powders of these three materials are mixed with a small amount of sodium polyacrylate and a pore-forming agent, and 20% water is added and mixed evenly. The mixture is then granulated to a particle size of 1-2 mm. After drying, firing, and sieving, the adsorption and filtration filter material is obtained. The mass percentage of the adsorption filter media material in the adsorption filter layer is as follows: 40% of the treated crayfish shell, 25% of zeolite, 25% of attapulgite, 5% of sodium polyacrylate, and 5% of pore-forming agent. A backwash drain valve 2-7 is provided at the end of the water inlet valve 2-3 of the adsorption filter box. A connecting valve 2-8 is provided between the bottom of the water storage tank 2-2 after adsorption filtration and the backwash water and air distribution space 2-4 at the bottom of the adsorption filter box 2-1. A bottom drain valve 2-9 is provided in the backwash water and air distribution space 2-4. A backwash air valve 2-10 is provided in the backwash water and air distribution space 2-4.

[0053] Centrifugal fan 3;

[0054] The air outlet 3-2 of the centrifugal fan 3 is connected to the backwash air pipe 1-8 and the backwash air pipe valve 2-10 via the air delivery pipe valve 3-3.

[0055] A method for removing heavy metals and fluoride ions in the wet recycling wastewater from lithium batteries includes the following steps:

[0056] A1: After the heavy metals and fluoride ions in the wet recovery wastewater of lithium battery are removed by the contact precipitation equipment 1, they enter the adsorption filtration equipment 2 for secondary deep removal through the submersible lift pump 1-12 set at the bottom of the sedimentation clear water tank 1-11, the lift pump outlet pipe 1-13 and the adsorption filter box inlet pipe 2-3 connected thereto.

[0057] A2: During adsorption filtration, the treated water enters the backwash water and air distribution space 2-4 through the inlet valve 2-3 of the adsorption filter box, the adsorption filter media layer 2-61, the support layer 2-6, and the filter plate and filter head assembly 2-5. The adsorption filtration effluent flows upward through the connecting pipe valve 2-8 into the adsorption filtration storage tank 2-2, and finally flows out through the outlet channel 2-12 of the adsorption filtration storage tank and the connected filtered water pipe 2-13 for recycling or discharge in compliance with standards.

[0058] A3: When treated water passes through the adsorption filter media layer 2-61, the special pores and open framework molecular structure of the filter material allow it to adsorb and remove large amounts of heavy metals and fluoride ions like a sponge. When the adsorption head of the water passing through the adsorption filter media layer 2-61 reaches the set value, backwashing is performed. During backwashing, first close the inlet valve 2-3 and the connecting valve 2-8 of the adsorption filter box, and then open the bottom drain valve 3-3. After 3 minutes, some water is drained from the backwash water and air distribution space 2-4, and the water level is lowered to 200 mm above the surface of the adsorption filter media layer 2-61. The top drain valve 2-11 of the adsorption filter media layer is opened to drain the water above the top drain valve 2-11. Then, the backwash air pipe valve 2-10 is opened to perform air backwashing to loosen the adsorption filter media layer 2-61 for 8 minutes. Then, the connecting pipe valve 2-8 and the backwash drain pipe valve 2-7 are opened for 4 minutes, so that the water in the adsorption and filtration water storage tank 2-2 flows from bottom to top through the backwash water and air distribution space 2-4, the filter plate and filter head assembly 2-5, and the support layer 2-6 to backwash the adsorption filter media layer 2-61.

[0059] A4: Finally, close the backwash drain valve 2-7 and open the inlet valve 2-3 of the adsorption filter box to restart adsorption filtration. The backwash cycle is 48 hours. The adsorption filtration rate of the adsorption filter equipment 2 is 2 m / h, the air flushing intensity is 12-16 L / S·㎡, and the water flushing intensity is 3-4 L / S·㎡. The air source for air and water flushing is supplied by the air outlet 3-2 of the centrifugal fan 3 through the backwash air valve 2-10.

[0060] A5: After secondary treatment by the adsorption filter media layer 2-61 of the adsorption filtration device 2, the heavy metals and fluoride ions in the wet recovery wastewater of lithium batteries can be reduced from low concentrations to the relevant national standards for water reuse or discharge.

[0061] The above are merely illustrative embodiments of the present invention and are not intended to limit the scope of the invention. Any equivalent changes and modifications made by those skilled in the art without departing from the concept and principles of the present invention should fall within the scope of protection of the present invention. Furthermore, it should be noted that the components of the present invention are not limited to the overall application described above. Each technical feature described in the specification can be used individually or in combination as needed. Therefore, the present invention naturally covers other combinations and specific applications related to the inventive points of this case.

Claims

1. A heavy metal and fluoride ion removal device for wet wastewater treatment in lithium battery recycling, characterized in that: include: Contact precipitation equipment (1); The upper outer wall of the contact sedimentation device (1) is connected to a contact sedimentation device inlet pipe (1-1), and the contact sedimentation device (1) is provided with a flow guide zone (1-2). A support plate (1-3) is provided in the lower middle part between the wall panel of the flow guide zone (1-2) and the tail box wall. A pad layer (1-4) is provided on the support plate (1-3). The top surface of the pad layer (1-4) has a contact material layer (1-5). The material of the contact material layer (1-5) is a mixture of 2-4 mm crayfish shells obtained by crushing and sieving after treatment, non-ionic polyacrylamide, and polyferric chloride. The thickness of the contact material layer (1-5) is 500 mm. Above the contact material layer (1-5) is a clear water zone (1-6). Below the support plate (1-3) is a backflushing air pipe (1-8). The lower part of the contact sedimentation device (1) is equipped with a sludge hopper (1-9). The bottom of the sludge hopper (1-9) is equipped with a sludge discharge pipe (1-10). The contact sedimentation device (1) is equipped with a sedimentation clear water tank (1-11). The contact sedimentation device (1) and the sedimentation clear water tank (1-11) are equipped with a water passage hole (1-7) on the common wall. The bottom of the sedimentation clear water tank (1-11) is equipped with a submersible lift pump (1-12). The submersible lift pump (1-12) is connected to a lift pump outlet pipe (1-13). Adsorption filtration equipment (2); The lower part of the adsorption filtration device (2) is an adsorption filter box (2-1), and the upper part is an adsorption filter water storage tank (2-2), which are separated by a steel partition. The upper part of the adsorption filter box (2-1) is provided with an adsorption filter box inlet valve (2-3), which is connected to the water outlet pipe (1-13) of the booster pump. The bottom plate of the adsorption filter box (2-1) and the bottom of the filter plate and filter head assembly (2-5) form a backwash water and air distribution space (2-4). A support layer (2-6) is provided on the filter plate and filter head assembly (2-5), and an adsorption filter media layer (2-61) is provided on the support layer (2-6). The adsorption filter media layer (2-61) contains adsorption... The filter media is made of processed crayfish shells, zeolite, and palygorskite, crushed to a particle size of less than 100 mesh. Then, a small amount of sodium polyacrylate and a pore-forming agent are added and mixed into dry powder. 20% water is added and the mixture is granulated to form a particle size of 1-2 mm. A backwash drain valve (2-7) is provided at the end of the inlet valve (2-3) of the adsorption filter box. A connecting valve (2-8) is provided between the bottom of the adsorption filter water storage tank (2-2) and the backwash water and air distribution space (2-4) at the bottom of the adsorption filter box (2-1). A bottom drain valve (2-9) is provided in the backwash water and air distribution space (2-4). A backwash air valve (2-10) is provided in the backwash water and air distribution space (2-4). Centrifugal fan (3); The air outlet (3-2) of the centrifugal fan (3) is connected to the backwash air pipe (1-8) and the backwash air pipe valve (2-10) respectively via the air delivery pipe valve (3-3).

2. The heavy metal and fluoride ion removal equipment for wet lithium battery recycling wastewater treatment according to claim 1, characterized in that: The contact sedimentation device (1) and the adsorption filtration device (2) both adopt an integrated box body and are made of corrosion-resistant carbon steel.

3. The heavy metal and fluoride ion removal equipment for wet lithium battery recycling wastewater treatment according to claim 1, characterized in that: The support plate (1-3) is made of steel plate with anti-corrosion material. The support plate (1-3) has holes with a diameter of 15mm and a hole spacing of 115mm. The support plate (1-3) is covered with nylon mesh with a specification of 36 mesh / inch.

4. The heavy metal and fluoride ion removal equipment for wet lithium battery recycling wastewater treatment according to claim 1, characterized in that: The subbase (1-4) is made of pebbles with a particle size of 16-25mm and a thickness of 100mm.

5. The heavy metal and fluoride ion removal equipment for wet lithium battery recycling wastewater treatment according to claim 1, characterized in that: The filter plate of the filter plate and filter head assembly (2-5) is made of steel plates spliced ​​together, and the size of a single filter plate is 980×980mm. At the same time, a hole is set on a single filter plate, and the diameter of the hole is 25mm. An adjustable ABS long-handled filter head is installed on the hole.

6. The heavy metal and fluoride ion removal equipment for wet lithium battery recycling wastewater treatment according to claim 1, characterized in that: The support layer (2-6) is made of quartz sand with a particle size of 2-4 mm and a thickness of 200 mm. The adsorption filter media layer (2-61) has a thickness of 1500 mm. The top of the adsorption filter media layer (2-61) is equipped with a top drain valve (2-11). The adsorption filter water storage tank (2-2) is designed with an adsorption filter water storage tank outlet channel (2-12) and a filtered water pipe (2-13) at the designed water level.

7. A method for removing heavy metals and fluoride ions in the treatment of wastewater from wet lithium battery recycling, comprising the heavy metal and fluoride ion removal equipment for the treatment of wastewater from wet lithium battery recycling as described in any one of claims 1 to 6, characterized in that: Includes the following steps: S1: Wastewater from the wet recycling of lithium batteries enters the guide zone (1-2) through the inlet pipe (1-1) of the contact sedimentation equipment, bypasses the guide plate, and enters the clear water zone (1-6) through the support plate (1-3), the pad layer (1-4), and the contact material layer (1-5). S2: The water enters the clear water tank (1-11) after sedimentation through the water passage (1-7) set on the common wall of the contact sedimentation equipment (1) and the clear water tank after sedimentation (1-11); S3: The water enters the adsorption filter box (2-1) of the adsorption filter equipment (2) through the submersible lift pump (1-12) and the lift pump outlet pipe (1-13) set at the bottom of the sedimentation clear water tank (1-11) and the inlet pipe valve (2-3) of the adsorption filter box connected thereto; S4: Most heavy metals and fluoride ions settle and are stored in the sludge hopper (1-9) after sludge-water separation due to the chelating effect of the contact material layer (1-5) on heavy metal ions and the flocculation effect on fluoride ions. A small portion is retained within the contact material layer (1-5). To avoid excessive head loss caused by the accumulation of sludge containing heavy metals and fluoride ions in the contact material layer (1-5) during operation, a backflushing air pipe (1-8) installed below the support plate (1-3) is used for periodic backflushing. The backwashing cycle is 7 days, the backwashing air intensity is 15L / (S·㎡), the backwashing time is 2-3min, the backwashing air source is supplied by the air outlet (3-2) of the centrifugal fan (3) through the air delivery valve (3-3) and the backwashing air pipe (1-8) connected thereto, the sludge in the sludge hopper (1-9) is discharged by the sludge discharge pipe (1-10) and is recycled and utilized by qualified units, the contact sedimentation time of the contact sedimentation equipment (1) is 20-30min; S5: After primary treatment by the contact material layer (1-5) of the contact precipitation device (1), the heavy metals and fluoride ions in the wet recovery wastewater of lithium batteries can be reduced from medium concentration to low concentration.

8. A method for removing heavy metals and fluoride ions in the treatment of wastewater from wet lithium battery recycling, comprising the heavy metal and fluoride ion removal equipment for the treatment of wastewater from wet lithium battery recycling as described in any one of claims 1 to 6, characterized in that: Includes the following steps: A1: After the heavy metals and fluoride ions in the wet recovery wastewater of lithium battery are removed by the contact precipitation equipment (1) for primary removal, they enter the adsorption filtration equipment (2) for secondary deep removal through the submersible lift pump (1-12), the lift pump outlet pipe (1-13) set at the bottom of the sedimentation clear water tank (1-11), and the inlet pipe valve (2-3) of the adsorption filter box connected thereto. A2: During adsorption filtration, the treated water enters the backwash water and air distribution space (2-4) through the inlet valve (2-3) of the adsorption filter box, the adsorption filter media layer (2-61), the support layer (2-6), and the filter plate and filter head assembly (2-5). The adsorption filtration effluent flows upward through the connecting pipe valve (2-8) into the adsorption filtration water storage tank (2-2), and finally flows out through the outlet channel (2-12) of the adsorption filtration water storage tank and the connected filtered water pipe (2-13) for recycling or discharge in compliance with standards. A3: When treated water passes through the adsorption filter media layer (2-61), the special pores and open framework molecular structure inside the filter material allow it to adsorb and remove large amounts of heavy metals and fluoride ions like a sponge. When the adsorption head of the water passing through the adsorption filter media layer (2-61) reaches the set value, backwashing is performed. During backwashing, first close the inlet valve (2-3) and connecting valve (2-8) of the adsorption filter box, and then open the bottom drain valve (2-9). After 3 minutes, drain some water from the backwash water and air distribution space (2-4) to lower the water level to 200 mm above the surface of the adsorption filter media layer (2-61). Open the top drain valve (2-11) of the adsorption filter media layer to drain the water above the top drain valve (2-11). Then open the backwash air pipe valve (2-10) to perform air backwashing to loosen the adsorption filter media layer (2-61) for 8 minutes. Then open the connecting pipe valve (2-8) and the backwash drain pipe valve (2-7) for 4 minutes to allow the water in the adsorption filter water tank (2-2) to flow from bottom to top through the backwash water and air distribution space (2-4), the filter plate and filter head assembly (2-5), and the support layer (2-6) to backwash the adsorption filter media layer (2-61). A4: Finally, close the backwash drain valve (2-7), open the inlet valve (2-3) of the adsorption filter box, and restart the adsorption filtration. The backwash cycle is 48 hours. The adsorption filtration rate of the adsorption filter equipment (2) is 2 m / h, the air flushing intensity is 12-16 L / (S·㎡), and the water flushing intensity is 3-4 L / (S·㎡). The air source for air and water flushing is supplied by the air outlet (3-2) of the centrifugal fan (3) through the backwash air valve (2-10). A5: After secondary treatment by the adsorption filter media layer (2-61) of the adsorption filtration equipment (2), the heavy metals and fluoride ions in the wet recovery wastewater of lithium battery can be reduced from low concentration to the standard for reuse or discharge of water.

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