A system and method for recycling and recovering lithium from waste lithium battery negative electrode materials by water leaching

Abstract

The application provides a waste lithium battery negative electrode material water immersion lithium extraction system and a resource recycling method, and relates to the technical field of solid waste lithium extraction. The waste lithium battery negative electrode material water immersion lithium extraction system comprises a tank body, the tank body is divided into a water immersion cavity and a separation cavity by a partition plate, a drainage pipe is arranged on the partition plate, a feeding pipe is arranged at the top of the tank body, and a first slag discharge pipe and a liquid discharge pipe are respectively arranged on the tank body. The waste lithium battery negative electrode material resource recycling method comprises the following steps: S1, slicing the waste lithium battery negative electrode, uniformly covering a eutectic NaOH-KOH mixture, and placing the mixture in a crucible. The automatic opening of the drainage pipe and the first slag discharge pipe is realized while the first telescopic part controls the first filter disc to switch from the stirring mode to the filtering mode; the first driving part can also be used for the rotary discharge of the first filter residue; so that the water immersion stirring of the material can be realized in one water immersion equipment, and the first separation and discharge and the second separation and discharge can be realized.

Description

Technical Field

[0001] This invention relates to the field of lithium extraction technology from solid waste, and more particularly to a water immersion lithium extraction system for waste lithium battery anode materials. Background Technology

[0002] Lithium extraction from waste lithium battery negative electrode sheets is a common lithium recycling method. It involves disassembling the waste battery to obtain positive and negative electrode sheets. The negative electrode sheets are pretreated to remove external contaminants that may be attached to the surface of the negative electrode sheets. The pretreated negative electrode sheets are then placed in a solution for lithium extraction.

[0003] In the relevant prior art, publication number CN117448580A discloses a water immersion lithium extraction device for waste lithium iron phosphate battery negative electrode sheets, belonging to the field of waste battery processing technology. The present invention adds a separation cylinder with an isolation sleeve to the outside of the water immersion cylinder for water immersion. During the water immersion process, the isolation sleeve shields multiple separation holes on the water immersion cylinder. The negative electrode sheet pulverized material and the aqueous solution are introduced into the water immersion cylinder and mixed to form an impregnation mixture. The impregnation mixture is transferred back and forth between the water immersion cylinder and the water tank by the cooperation of the suction component and the communication component.

[0004] Using existing water immersion equipment, after sufficient water immersion and stirring of the mixture, since the mixture contains different components, additional filtration equipment is needed to separate the different components in the mixture in sequence. A single device is not convenient to simultaneously achieve water immersion mixing and two-stage filtration separation of the materials.

[0005] Therefore, it is necessary to provide a water immersion lithium extraction system for waste lithium battery anode materials to solve the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides a water immersion lithium extraction system for waste lithium battery negative electrode materials, which solves the problem in related technologies that it is inconvenient for a single device to simultaneously perform water immersion mixing and two-stage filtration separation of materials.

[0007] To solve the above-mentioned technical problems, the present invention provides a water immersion lithium extraction system for waste lithium battery negative electrode materials, comprising:

[0008] The tank body is divided into a water immersion chamber and a separation chamber by a partition. A drainage pipe is provided on the partition. A feed pipe is provided on the top of the tank body. A first slag discharge pipe and a liquid discharge pipe are respectively installed on the tank body. The first slag discharge pipe is connected to the water immersion chamber, and the liquid discharge pipe is connected to the separation chamber.

[0009] A stirring assembly includes a first driving member, a first driving shaft, and a stirring rod. The fixed part of the first driving member is fixedly disposed on the top of the tank. The top of the first driving shaft passes through the tank and is fixedly connected to the driving part of the first driving member. The stirring rod is fixedly disposed on the first driving shaft. The bottom of the first driving shaft is rotatably connected to the partition.

[0010] The first separation component includes a sliding cover, a first filter disc, and a first telescopic member. The sliding cover is slidably installed inside the tank and located within the water immersion chamber. The sliding cover has a switch hole. The first filter disc is fixed to the bottom of the sliding cover, and a switch disc is fixed to the bottom of the first filter disc. The fixed part of the first telescopic member is fixed to the partition plate. The telescopic part of the first telescopic member passes through the partition plate and is fixedly connected to the sliding cover. The first filter disc is used for primary filtration of the mixture after water immersion.

[0011] The second separation component is disposed at the output end of the drainage tube and is used for secondary filtration of the mixture after water immersion.

[0012] The first slag discharge pipe is aligned with the lifting path of the switch hole; when the switch plate is closed, the switch plate is inserted into the drain pipe, and the water immersion chamber is isolated from the separation chamber; when the switch plate is open, the water immersion chamber is connected to the separation chamber through the drain pipe.

[0013] Preferably, the second separation component includes a second driving member, a second driving shaft, a switching disk, and a movable filter. The fixed part of the second driving member is fixedly disposed at the bottom of the tank. The bottom of the second driving shaft passes through the tank and is fixedly connected to the driving part of the second driving member. The bottom of the switching disk is fixedly disposed at the top of the second driving shaft. A docking hole is provided on the switching disk. The movable filter is installed on the switching disk and located in the docking hole. The docking hole is correspondingly disposed to the output end of the drain pipe.

[0014] There are two docking holes, and each docking hole corresponds to one of the movable filter elements.

[0015] Preferably, the movable filter element includes a second filter disc, a second telescopic member, and a connecting slide rod. The second filter disc is inserted into the docking hole and slidably connected to the switching disc. The two ends of the second telescopic member are fixedly connected to the switching disc and the connecting slide rod, and the top of the connecting slide rod is fixedly connected to the second filter disc.

[0016] The bottom of the tank is provided with a second slag discharge pipe, and a flow guide scraper is fixed inside the tank. The bottom of the flow guide scraper slides in contact with the top of the switching disc, and the flow guide range of the flow guide scraper is aligned with the material receiving range of the second slag discharge pipe.

[0017] Preferably, the second telescopic member is an elastic support member, and both ends of the second telescopic member are elastically connected to the switching disk and the connecting slide rod;

[0018] The second separation component also includes a support slide cylinder, the top of which is provided with an inclined structure, and the bottom of the connecting slide rod slides against the top of the support slide cylinder;

[0019] When the connecting slide is at the bottom of the inclined structure, the second filter disc is fully retracted; when the connecting slide is at the top of the inclined structure, the second filter disc is fully extended.

[0020] Preferably, the bottom of the tank is provided with at least three support legs.

[0021] Preferably, the second separation component may not include the second drive member and the second drive shaft, and the bottom of the first drive shaft passes through the partition and is fixedly connected to the switching disk.

[0022] This invention also provides a method for the resource recycling of waste lithium battery negative electrode materials, comprising the following steps:

[0023] Step S1: Cut the waste lithium battery negative electrode into slices, evenly cover them with a eutectic NaOH-KOH mixture, place them in a crucible, and bake them in a tube furnace to obtain the baked product.

[0024] Step S2: The baked product is mixed with deionized water and injected into the waste lithium battery negative electrode material water immersion lithium extraction system. After stirring and filtration, graphite, copper foil and lithium-containing solution are obtained.

[0025] Step S3: The lithium-containing solution is further purified by selectively adsorbing lithium through an ion sieve.

[0026] Step S4: Wash the graphite with ultrapure water to remove residual alkali and fluorine compounds, and freeze-dry to obtain pure graphite.

[0027] Step S5: Pure graphite and sodium hypochlorite are added to the solution of the organic dye Rhodamine B to degrade the organic dye Rhodamine B.

[0028] Preferably, the specifications of the waste lithium battery negative electrode slice are 10mm×20mm.

[0029] Preferably, the eutectic NaOH-KOH mixture is prepared by stirring sodium hydroxide and potassium hydroxide at a molar ratio of 1:1 at low speed.

[0030] Preferably, the ion screening uses λ-MnO2.

[0031] Compared with related technologies, the water immersion lithium extraction system for waste lithium battery anode materials provided by this invention has the following beneficial effects:

[0032] The first telescopic component controls the first filter disc to switch from stirring mode to filtering mode, while the first slag discharge pipe and the first slag discharge pipe are automatically opened. The first drive component can also be used for the rotation and discharge of filter residue. This allows for the water immersion and stirring of materials, as well as primary slag discharge and secondary liquid discharge, all within a single water immersion device. Attached Figure Description

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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 the structures shown in these drawings without creative effort.

[0034] Figure 1 A three-dimensional diagram of a first embodiment of a water immersion lithium extraction system for waste lithium battery anode materials provided by the present invention;

[0035] Figure 2 for Figure 1 A 3D view of a partial cross-section of the tank shown;

[0036] Figure 3 for Figure 1 A schematic diagram of the cross-sectional structure of section AA shown;

[0037] Figure 4 for Figure 1 A schematic diagram of the cross-sectional structure of section BB shown;

[0038] Figure 5 for Figure 4 The diagram shown illustrates the mode switching principle of the first filter disk. Figure 5 (a) in the diagram is a state diagram of the first filter disc moving upwards. Figure 5 (b) in the diagram shows the state of the first filter disk in filtering mode;

[0039] Figure 6 for Figure 5 A cross-sectional structural diagram of the CC section shown in (b) of the diagram;

[0040] Figure 7 for Figure 4 A partial 3D view of the second filter disc connection structure shown;

[0041] Figure 8 for Figure 4 A schematic diagram of the cross-sectional structure of the DD section shown;

[0042] Figure 9 This is a schematic diagram of the second embodiment of a water immersion lithium extraction system for waste lithium battery anode materials provided by the present invention.

[0043] Explanation of icon numbers:

[0044] 1. Tank body; 10. Baffle plate; 100. Water immersion chamber; 200. Separation chamber; 101. Drainage pipe; 11. Feed pipe; 12. First slag discharge pipe; 13. Liquid discharge pipe; 14. Second slag discharge pipe;

[0045] 2. Stirring assembly; 21. First driving component; 22. First drive shaft; 23. Stirring rod;

[0046] 3. First separation component; 31. Sliding cover; 311. Switch hole; 32. First filter disc; 321. Switch disc; 33. First telescopic component;

[0047] 4. Second separation assembly; 41. Second drive component; 42. Second drive shaft; 43. Switching disc; 430. Docking hole; 44. Supporting slide cylinder; 45. Movable filter element; 451. Second filter disc; 452. Second telescopic component; 453. Connecting slide rod;

[0048] 5. Drainage scraper.

[0049] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0050] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0051] This invention provides a water leaching lithium extraction system for waste lithium battery anode materials.

[0052] First embodiment.

[0053] Please refer to the following: Figures 1 to 4 In this invention, a water leaching lithium extraction system for waste lithium battery negative electrode materials includes:

[0054] Tank 1, the tank 1 is divided into a water immersion chamber 100 and a separation chamber 200 by a partition 10, a drainage pipe 101 is provided on the partition 10, a feed pipe 11 is provided on the top of the tank 1, a first slag discharge pipe 12 and a liquid discharge pipe 13 are respectively installed on the tank 1, the first slag discharge pipe 12 is connected to the water immersion chamber 100, and the liquid discharge pipe 13 is connected to the separation chamber 200;

[0055] The stirring assembly 2 includes a first driving member 21, a first driving shaft 22, and a stirring rod 23. The fixed part of the first driving member 21 is fixedly disposed on the top of the tank body 1. The top of the first driving shaft 22 passes through the tank body 1 and is fixedly connected to the driving part of the first driving member 21. The stirring rod 23 is fixedly disposed on the first driving shaft 22. The bottom of the first driving shaft 22 is rotatably connected to the partition plate 10.

[0056] The first separation component 3 includes a sliding cover 31, a first filter disc 32, and a first telescopic component 33. The sliding cover 31 is slidably installed inside the tank 1 and located within the water immersion chamber 100. A switch hole 311 is provided on the sliding cover 31. The first filter disc 32 is fixedly installed at the bottom of the sliding cover 31, and a switch disc 321 is fixedly installed at the bottom of the first filter disc 32. The fixed part of the first telescopic component 33 is fixedly installed on the partition 10. The telescopic part of the first telescopic component 33 passes through the partition 10 and is fixedly connected to the sliding cover 31. The first filter disc 32 is used for primary filtration of the mixture after water immersion.

[0057] The second separation component 4 is disposed at the output end of the drain pipe 101 and is used for secondary filtration of the mixture after water immersion.

[0058] The first slag discharge pipe 12 is aligned with the lifting path of the switch hole 311; when the switch disk 321 is closed, the switch disk 321 is inserted into the drain pipe 101, and the water immersion chamber 100 is isolated from the separation chamber 200; when the switch disk 321 is open, the water immersion chamber 100 is connected to the separation chamber 200 through the drain pipe 101.

[0059] The feed pipe 11 is used to inject waste lithium battery negative electrode material that needs to be immersed in water and deionized water to form a mixture.

[0060] The first filter disc 32 is used to filter and separate the copper foil in the mixture, while the graphite and lithium-containing solution pass through the first filter disc 32.

[0061] In this embodiment, the first telescopic member 33 is any one of an electric telescopic rod, a hydraulic telescopic cylinder, or a telescopic cylinder, used to switch the usage mode of the first filter disc 32.

[0062] In this embodiment, the first filter disc 32 includes two usage modes:

[0063] In stirring mode, the sliding cover 31 moves completely downward, the first filter plate 32 abuts against the partition plate 10, the switch hole 311 is misaligned and separated from the first slag outlet pipe 12, and the first slag outlet pipe 12 is closed; the switch plate 321 is inserted into the guide pipe 101, so that the guide pipe 101 is closed, which facilitates the water immersion stirring of the material in the water immersion chamber 100.

[0064] In the filtration mode, the sliding cover 31 moves completely upward, and after the first filter plate 32 separates from the partition plate 10, the top of the first filter plate 32 slides into contact with the stirring rod 23. The switch hole 311 is aligned and connected with the first slag discharge pipe 12, and the switch plate 321 separates from the guide pipe 101, so that the guide pipe 101 is opened, facilitating the primary filtration of the material in the water immersion chamber 100 after water immersion and stirring.

[0065] The first driving component 21 is a motor structure, which is used to directly drive the first driving shaft 22 and the stirring rod 23 to rotate. The stirring rod 23 has an arc-shaped structure, which is used for water immersion stirring of materials on the one hand, and for discharging primary filter residue on the other hand.

[0066] After the first filter plate 32 filters the mixture once, it forms a primary filter residue and a primary filtrate. After the first filter plate 32 is adjusted to the filtration mode, the primary filter residue will be pushed by the stirring rod 23 to discharge from the switch hole 311 and the first slag outlet pipe 12, so that the primary filter residue can be discharged after separation by the power of the first driving component 21.

[0067] While the first filter plate 32 is adjusted upward, the first filter plate 32 drives the switch plate 321 to move upward, so that the switch plate 321 is separated from the drainage pipe 101. The drainage pipe 101 conveys the primary filtrate downward. After being separated and filtered by the second separation component 4, the primary filtrate is filtered twice.

[0068] While the first telescopic component 33 controls the first filter disc 32 to switch from stirring mode to filtering mode, the first guide pipe 101 and the first slag discharge pipe 12 are automatically opened; the first drive component 21 can also be used for the rotation discharge of filter residue in one step; so that the water immersion stirring of the material can be realized in one water immersion device, and the slag discharge can be separated in one step and the liquid discharge can be separated in two steps.

[0069] One water immersion device can realize water immersion and mixing of mixed materials, primary filtration and separation, primary filter residue discharge, secondary filtration and separation, and secondary filtrate discharge.

[0070] For details, please refer to the following: Figure 3 and Figure 4 The second separation component 4 includes a second drive member 41, a second drive shaft 42, a switching disk 43, and a movable filter 45. The fixed part of the second drive member 41 is fixedly disposed at the bottom of the tank body 1. The bottom of the second drive shaft 42 passes through the tank body 1 and is fixedly connected to the drive part of the second drive member 41. The bottom of the switching disk 43 is fixedly disposed at the top of the second drive shaft 42. A docking hole 430 is provided on the switching disk 43. The movable filter 45 is installed on the switching disk 43 and located in the docking hole 430. The docking hole 430 is correspondingly disposed to the output end of the drainage pipe 101.

[0071] There are two docking holes 430, and each docking hole 430 corresponds to one of the movable filter elements 45.

[0072] At least two of the said docking holes 430 facilitate that if one of the said movable filter elements 45 becomes clogged, the other of the said movable filter elements 45 can continue to perform filtration.

[0073] In this embodiment, the second driving component 41 can be a motor structure, used to directly drive the switching disk 43 to rotate, so that the switching disk 43 can drive the two docking holes 430 and the two movable filter components 45 to switch work positions.

[0074] The movable filter element 45 is used to filter the filtrate passing through the drainage tube 101. After one movable filter element 45 has filtered, the second drive shaft 42 and the switching disk 43 can be rotated by the second drive element 41. When the switching disk 43 rotates, it drives at least two movable filter elements 45 to rotate and switch, so as to facilitate continuous filtration of the filtrate in the drainage tube 101.

[0075] In a preferred embodiment of this example, four docking holes 430 are provided, and each docking hole 430 corresponds one-to-one with a movable filter element 45. Increasing the number of movable filter elements 45 facilitates continuous drainage and filtration of the filtrate during the subsequent continuous rotation of the switching disc 43.

[0076] In an optional embodiment of this example, the movable filter element 45 can be an independent filter structure, which can be directly installed within the range of the docking hole 430.

[0077] In another optional implementation of this embodiment, please refer to the following: Figure 4 , Figure 7 and Figure 8 The movable filter element 45 includes a second filter disc 451, a second telescopic member 452, and a connecting slide rod 453. The second filter disc 451 is inserted into the docking hole 430 and slidably connected to the switching disc 43. The two ends of the second telescopic member 452 are fixedly connected to the switching disc 43 and the connecting slide rod 453. The top of the connecting slide rod 453 is fixedly connected to the second filter disc 451.

[0078] The bottom of the tank body 1 is provided with a second slag discharge pipe 14, and a flow guide scraper 5 is fixed inside the tank body 1. The bottom of the flow guide scraper 5 is in sliding contact with the top of the switching disk 43, and the flow guide range of the flow guide scraper 5 is aligned with the material receiving range of the second slag discharge pipe 14.

[0079] In this embodiment, after the mixture is filtered by the first filter plate 32, the primary filter residue is located above the first filter plate 32, and the primary filtrate is discharged downward through the opened drain pipe 101.

[0080] The second filter plate 451 is used to filter and separate the graphite in the primary filtrate, while the lithium-containing solution passes through the second filter plate 451.

[0081] The primary filtrate is filtered through the second filter plate 451 to form secondary filter residue and secondary filtrate. The secondary filter residue is collected above the second filter plate 451, while the secondary filtrate flows downward through the docking hole 430 and is discharged outward through the drain pipe 13.

[0082] In this embodiment, the second telescopic member 452 is used to control the lifting and lowering adjustment of the second filter disc 451. When the docking hole 430 is connected to the drainage pipe 101 vertically, the second filter disc 451 moves down to facilitate the filtration and separation of the primary filtrate.

[0083] When the docking hole 430 is rotated and misaligned with the drainage pipe 101, the second filter plate 451 moves upward, which facilitates the lifting of the secondary filter residue to the top surface of the switching plate 43.

[0084] The principle of rotary ash discharge for secondary filter cake:

[0085] First, start the second drive unit 41. The second drive unit 41 drives the switching disk 43 to rotate counterclockwise through the second drive shaft 42. The switching disk 43 drives the docking hole 430 and the second filter disk 451 to separate from the output end of the drain pipe 101.

[0086] Then activate the second telescopic component 452. The second telescopic component 452 drives the second filter disc 451 to move upward through the connecting slide rod 453. The second filter disc 451 drives the secondary filter residue collected by filtration to the top surface of the switching disc 43.

[0087] When the switching disk 43 drives the secondary filter residue on the top surface of the switching disk 43 to rotate counterclockwise, it gradually comes into contact with the guiding scraper 5. Under the scraping action of the guiding scraper 5, the secondary filter residue adaptively discharges towards the receiving direction of the second slag outlet pipe 14, which facilitates the automatic discharge of the secondary filter residue collected in the docking hole 430.

[0088] In an optional embodiment of this example, the second telescopic member 452 can be any one of an electric telescopic rod, a hydraulic telescopic cylinder, or a telescopic cylinder, used to directly drive the lifting and lowering adjustment of the connecting slide rod 453 and the second filter disc 451.

[0089] In another optional implementation of this embodiment, please refer to the following: Figure 4 and Figure 7 The second telescopic member 452 is an elastic support member, and the two ends of the second telescopic member 452 are elastically connected to the switching disk 43 and the connecting slide rod 453;

[0090] The second separation component 4 also includes a support slide cylinder 44, the top of which is provided with an inclined structure, and the bottom of the connecting slide rod 453 slides against the top of the support slide cylinder 44;

[0091] When the connecting slide bar 453 is at the bottom of the inclined structure, the second filter disc 451 is fully retracted; when the connecting slide bar 453 is at the top of the inclined structure, the second filter disc 451 is fully extended.

[0092] The second telescopic member 452 is used to elastically press the connecting slide rod 453, so that the bottom of the connecting slide rod 453 slides stably against the top of the supporting slide cylinder 44.

[0093] In this embodiment, the second filter disc 451 includes two states;

[0094] Filtration and collection state: The connecting slide bar 453 is located in the bottom area of ​​the inclined structure, and the second filter disc 451 retracts to the bottom of the docking hole 430, so that the interior of the docking hole 430 forms a receiving space for temporary receiving, filtering and storing the secondary filter residue.

[0095] Lifting and discharging state: The connecting slide rod 453 is located in the top area of ​​the inclined structure, and the top surface of the second filter plate 451 and the top surface of the switching plate 43 are on the same plane, so that the secondary filter residue stored in the docking hole 430 is automatically lifted to the top surface of the switching plate 43.

[0096] Automatic lifting principle:

[0097] Let's define it, such as Figure 4 As shown, in the initial state, the docking hole 430 is aligned with the output end of the drainage tube 101, and the second filter plate 451 is in the filtration and collection state, which facilitates the secondary filtration of the primary filtrate output by the drainage tube 101.

[0098] During the secondary filtration, the second drive unit 41 is activated. The second drive unit 41 drives the switching disk 43 to rotate counterclockwise via the second drive shaft 42. The switching disk 43 drives the connecting slide rod 453 and the second filter disk 451 to rotate counterclockwise via the second telescopic member 452. The connecting slide rod 453 slides along the top of the support slide cylinder 44.

[0099] The connecting slide rod 453 slides from the bottom region to the top region along the inclined structure, so that the connecting slide rod 453 rotates and moves upward adaptively. The connecting slide rod 453 drives the second filter disk 451 to rise, so that the secondary filter residue collected in the docking hole 430 is raised to the top surface of the switching disk 43, and the second filter disk 451 switches from the filtration and collection state to the raised and discharged state.

[0100] As the switching disk 43 continues to rotate, under the obstruction of the inclined guide scraper 5, the guide scraper 5 adaptively scrapes the raised secondary filter residue to the receiving area of ​​the second slag discharge pipe 14, so that the secondary filter residue is automatically discharged through the second slag discharge pipe 14.

[0101] The rotational power of the switching disc 43 facilitates adaptive switching of the state of the second filter disc 451. Simultaneously, when the second filter disc 451 is in the raised discharge state, the secondary filter residue is automatically discharged to the receiving range of the second discharge pipe 14. This allows for simultaneous secondary filtration, separation, and separate discharge of the primary filtrate.

[0102] Specifically, the bottom of the tank 1 is provided with at least three support legs. These legs are used to stably raise the tank 1, so that sufficient installation and adjustment clearance is reserved between the bottom of the tank 1 and the ground.

[0103] The working principle of the water immersion lithium extraction system for waste lithium battery negative electrode materials provided in this embodiment is as follows:

[0104] Let's define it as follows: In the initial state, the first filter plate 32 is in stirring mode, the docking hole 430 is aligned with the drain pipe 101, and the drain pipe 101 is closed.

[0105] A1, material mixing process: First, the mixture that needs to be mixed with water is added into the tank 1 through the feed pipe 11, and the mixture is kept above the partition 10;

[0106] The first driving component 21 is activated, and the first driving component 21 drives the stirring rod 23 to rotate through the first driving shaft 22. The stirring rod 23 drives the mixture on the partition 10 to be water-immersed and stirred, so as to facilitate the water immersion treatment of the waste battery negative electrode material.

[0107] A2, after the mixture is soaked in water, the first telescopic component 33 is activated. The first telescopic component 33 drives the sliding cover 31, the first filter plate 32 and the switch plate 321 to move upward synchronously, so that the first filter plate 32 switches from the stirring mode to the filtering mode.

[0108] When the first filter plate 32 moves upward, the first filter plate 32 performs a first filtration on the water-soaked mixture to form a separated primary filter residue and a primary filtrate. The primary filter residue is stored above the first filter plate 32.

[0109] like Figure 5 As shown in (a), before the first slag discharge pipe 12 is opened, the first filter plate 32 first drives the switch plate 321 to separate from the guide pipe 101, so that the guide pipe 101 is opened. The primary filtrate is conveyed downward through the guide pipe 101. The primary filtrate is filtered and separated by the second filter plate 451 to form secondary filter residue and secondary filtrate. The secondary filter residue is stored on the top of the second filter plate 451 in the contracted state and is collected in the range of the docking hole 430, so that the liquid surface of the primary filtrate in the range of the water immersion chamber 100 is discharged downward to below the discharge range of the first slag discharge pipe 12, so as to prevent the primary filtrate from leaking out from the first slag discharge pipe 12.

[0110] like Figure 5 (a) to Figure 5 As shown in (b), the top of the first filter plate 32 then slides into contact with the bottom of the stirring rod 23, and the switch hole 311 connects with the first slag discharge pipe 12, so that the first slag discharge pipe 12 is opened. When the stirring rod 23 continues to rotate, it uses centrifugal force to push the primary filter residue on the first filter plate 32 into the first slag discharge pipe 12, so that the primary filter residue is discharged separately.

[0111] The secondary filtrate is discharged downward through the second filter plate 451 into the separation chamber 200, and then discharged separately through the drain pipe 13;

[0112] A3, when it is necessary to discharge the collected secondary filter residue, the second drive component 41 is activated. The second drive component 41 drives the switching disk 43 to rotate through the second drive shaft 42. The switching disk 43 drives the second filter disk 451, the connecting slide rod 453 and the second telescopic component 452 to rotate counterclockwise as a whole. The connecting slide rod 453 slides along the top of the support slide cylinder 44.

[0113] When the connecting slide rod 453 slides, it first slides from the bottom of the inclined structure toward the top of the inclined structure. The connecting slide rod 453 slides upward adaptively, and the connecting slide rod 453 drives the second filter disk 451 to move upward synchronously, so that the second filter disk 451 pushes the secondary filter residue collected in the docking hole 430 to the top surface of the switching disk 43.

[0114] When the connecting slide bar 453 slides along the top of the inclined structure, the switching disk 43 drives the pushed secondary filter residue to slide into contact with the diversion scraper 5, so that the diversion scraper 5 adaptively pushes the secondary filter residue to the receiving range of the second slag outlet pipe 14 for adaptive delivery, and the second slag outlet pipe 14 discharges the separated secondary filter residue separately.

[0115] When the connecting slide rod 453 slides from the top of the inclined structure to the bottom of the inclined structure, the second telescopic member 452 elastically pushes the connecting slide rod 453 to slide down adaptively. The connecting slide rod 453 drives the second filter disc 451 to move down synchronously, so that the second filter disc 451 shrinks and resets after the secondary filter residue is discharged, which facilitates the subsequent filtration of the primary filtrate.

[0116] The first telescopic component 33 enables the first filter disc 32 to switch modes. When the first filter disc 32 switches from stirring mode to filtering mode, it not only achieves the filtration and separation of the mixed materials, but also automatically opens and drains the liquid from the drain pipe 101. The rotational power of the stirring rod 23 also enables the discharge of the filter residue from the first filter disc 32.

[0117] Simultaneously, during the process of rotating the switching disk 43 to switch the docking hole 430, the automatic upward pushing of the secondary filter residue and the automatic scraping and discharge of the secondary filter residue are also realized.

[0118] Second embodiment:

[0119] Please see Figure 9Based on the water immersion lithium extraction system for waste lithium battery anode materials provided in the first embodiment of the present invention, the second embodiment of the present invention proposes another water immersion lithium extraction system for waste lithium battery anode materials. The second embodiment is merely a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the separate implementation of the first embodiment.

[0120] Specifically, the difference in the water immersion lithium extraction system for waste lithium battery negative electrode materials provided in the second embodiment of the present invention is that the second separation component 4 may not include the second drive component 41 and the second drive shaft 42, and the bottom of the first drive shaft 22 passes through the partition 10 and is fixedly connected to the switching disk 43.

[0121] In this embodiment, the rotation of the switching disk 43 no longer requires power from the second drive member 41 and the second drive shaft 42.

[0122] The first drive shaft 22 and the partition 10 are rotated and sealed to ensure the sealing performance when the water immersion chamber 100 and the separation chamber 200 are isolated.

[0123] Instead, the switching disk 43 is driven to rotate synchronously by the driving action of the first driving component 21, so that under the control of the first driving component 21, it can be used for stirring materials, rotating and discharging primary filter residue after primary separation, rotating and switching secondary filter residue after secondary separation, automatic lifting and automatic material discharge.

[0124] The working principle of a water immersion lithium extraction system for waste lithium battery negative electrode materials provided in this embodiment is as follows:

[0125] After the material in the water immersion chamber 100 has been immersed in water, the rotation of the first drive shaft 22 and the stirring rod 23 is maintained.

[0126] The first telescopic component 33 controls the first filter disc 32 to switch from stirring mode to filtering mode. While the stirring rod 23 rotates, it also drives the first filter disc 32 to rotate and discharge the filtrate from the previous time.

[0127] On the other hand, the first drive shaft 22 also drives the switching disk 43 to rotate synchronously, realizing the switching of the working position of the first filter disk 32; when the docking hole 430 is connected to the drainage pipe 101, the primary filtrate in the drainage pipe 101 is filtered for secondary filtration through the second filter disk 451, so that the secondary filter residue is collected in the docking hole 430, and the secondary filtrate falls into the range of the separation chamber 200, so that the secondary filtrate is transported and discharged to the outside through the drain pipe 13;

[0128] When the switching disk 43 rotates, the switching disk 43 also drives the connecting slide rod 453 to rotate. The connecting slide rod 453 slides counterclockwise along the top of the supporting slide cylinder 44. When the connecting slide rod 453 slides from the bottom to the top along the inclined structure, the connecting slide rod 453 drives the second filter disk 451 to move upward adaptively, so that the second filter disk 451 automatically switches from the filtration shrinkage state to the lifting and slag discharge state, so that the secondary filter slag collected in the docking hole 430 is lifted to the top surface of the switching disk 43.

[0129] As the switching disk 43 continues to rotate, it drives the secondary filter residue in the slag discharge state to move toward the blocking range of the guiding scraper 5. This allows the secondary filter residue to be adaptively pushed toward the receiving range of the second slag discharge pipe 14 while the switching disk 43 rotates, facilitating the separate discharge of the secondary filter residue through the second slag discharge pipe 14.

[0130] Ultimately, under the driving action of the first driving component 21, it can be used for water immersion stirring of materials, rotary discharge of primary filter residue, and rotary discharge of secondary filter residue. This facilitates the separate discharge of primary filter residue, secondary filter residue, and secondary filtrate within the tank 1.

[0131] A method for resource recycling of waste lithium battery negative electrode materials.

[0132] The method for resource recycling of waste lithium battery negative electrode materials includes the following steps:

[0133] Step S1: Cut the waste lithium battery negative electrode into slices, evenly cover them with a eutectic NaOH-KOH mixture, place them in a crucible, and bake them in a tube furnace to obtain the baked product.

[0134] Step S2: The baked product is mixed with deionized water and injected into the waste lithium battery negative electrode material water immersion lithium extraction system. After stirring and filtration, graphite, copper foil and lithium-containing solution are obtained.

[0135] Step S3: The lithium-containing solution is further purified by selectively adsorbing lithium through an ion sieve.

[0136] Step S4: Wash the graphite with ultrapure water to remove residual alkali and fluorine compounds, and freeze-dry to obtain pure graphite.

[0137] Step S5: Pure graphite and sodium hypochlorite are added to the solution of the organic dye Rhodamine B to degrade the organic dye Rhodamine B.

[0138] The specifications of the waste lithium battery negative electrode slices are 10mm×20mm.

[0139] The eutectic NaOH-KOH mixture is prepared by stirring sodium hydroxide and potassium hydroxide at a low speed in a 1:1 molar ratio.

[0140] The ion screening uses λ-MnO2.

[0141] Beneficial effects:

[0142] Using a low-melting-point eutectic NaOH-KOH mixture as the reaction medium, efficient separation of graphite and copper foil is achieved, significantly reducing energy consumption. The recovered graphite is directly used as an environmental catalyst, realizing the high-value utilization of waste graphite and reducing waste emissions.

[0143] Case 1:

[0144] S1. Cut the waste lithium battery negative electrode into 10mm×20mm pieces, evenly cover with eutectic NaOH-KOH mixture, place in a nickel crucible, and bake in a tube furnace at 150℃ for 20min to obtain the baked product.

[0145] The eutectic NaOH-KOH mixture was prepared by stirring sodium hydroxide and potassium hydroxide (1:1 molar ratio) at low speed for 30 minutes, filtering through a 200-mesh sieve to remove lumps, and storing it in a sealed glass bottle.

[0146] S2. The baked product is mixed with deionized water and injected into the water immersion lithium extraction system of the waste lithium battery negative electrode material. The mixture is stirred at room temperature for 2 hours and then filtered to obtain graphite, copper foil and lithium-containing solution.

[0147] S3. Lithium-containing solutions are further purified by selectively adsorbing lithium using ion sieves.

[0148] S4. Wash the graphite with ultrapure water multiple times to remove residual alkali and fluorine-containing compounds, and freeze-dry to obtain pure graphite.

[0149] S5. Add 0.075g of pure graphite and 0.5mL of sodium hypochlorite to 0.5mL of the organic dye Rhodamine B solution to degrade the organic dye Rhodamine B.

[0150] Pure graphite exhibits excellent catalytic properties, and can catalyze the oxidative degradation of the organic dye Rhodamine B by sodium hypochlorite, with a degradation rate of over 98%.

[0151] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made under the concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A water immersion lithium extraction system for waste lithium battery negative electrode materials, characterized in that, include: The tank body is divided into a water immersion chamber and a separation chamber by a partition. A drainage pipe is provided on the partition. A feed pipe is provided on the top of the tank body. A first slag discharge pipe and a liquid discharge pipe are respectively installed on the tank body. The first slag discharge pipe is connected to the water immersion chamber, and the liquid discharge pipe is connected to the separation chamber. A stirring assembly includes a first driving member, a first driving shaft, and a stirring rod. The fixed part of the first driving member is fixedly disposed on the top of the tank. The top of the first driving shaft passes through the tank and is fixedly connected to the driving part of the first driving member. The stirring rod is fixedly disposed on the first driving shaft. The bottom of the first driving shaft is rotatably connected to the partition. The first separation component includes a sliding cover, a first filter disc, and a first telescopic member. The sliding cover is slidably installed inside the tank and located within the water immersion chamber. The sliding cover has a switch hole. The first filter disc is fixed to the bottom of the sliding cover, and a switch disc is fixed to the bottom of the first filter disc. The fixed part of the first telescopic member is fixed to the partition plate. The telescopic part of the first telescopic member passes through the partition plate and is fixedly connected to the sliding cover. The first filter disc is used for primary filtration of the mixture after water immersion. The second separation component is disposed at the output end of the drainage tube and is used for secondary filtration of the mixture after water immersion. The first slag discharge pipe is aligned with the lifting path of the switch hole; when the switch plate is closed, the switch plate is inserted into the drain pipe, and the water immersion chamber is isolated from the separation chamber. When the switch panel is opened, the water immersion chamber is connected to the separation chamber through the drainage pipe.

2. The water immersion lithium extraction system for waste lithium battery negative electrode materials according to claim 1, characterized in that, The second separation component includes a second drive unit, a second drive shaft, a switching disk, and a movable filter. The fixed part of the second drive unit is fixedly disposed at the bottom of the tank. The bottom of the second drive shaft passes through the tank and is fixedly connected to the drive part of the second drive unit. The bottom of the switching disk is fixedly disposed at the top of the second drive shaft. A docking hole is provided on the switching disk. The movable filter is installed on the switching disk and located in the docking hole. The docking hole is correspondingly disposed to the output end of the drain pipe. There are two docking holes, and each docking hole corresponds to one of the movable filter elements.

3. The water immersion lithium extraction system for waste lithium battery negative electrode materials according to claim 2, characterized in that, The movable filter element includes a second filter disc, a second telescopic component, and a connecting slide rod. The second filter disc is inserted into the docking hole and slidably connected to the switching disc. The two ends of the second telescopic component are fixedly connected to the switching disc and the connecting slide rod, and the top of the connecting slide rod is fixedly connected to the second filter disc. The bottom of the tank is provided with a second slag discharge pipe, and a flow guide scraper is fixed inside the tank. The bottom of the flow guide scraper slides in contact with the top of the switching disc, and the flow guide range of the flow guide scraper is aligned with the material receiving range of the second slag discharge pipe.

4. The water immersion lithium extraction system for waste lithium battery negative electrode materials according to claim 3, characterized in that, The second telescopic component is an elastic support component, and its two ends are elastically connected to the switching disk and the connecting slide rod; The second separation component also includes a support slide cylinder, the top of which is provided with an inclined structure, and the bottom of the connecting slide rod slides against the top of the support slide cylinder; When the connecting slide rod is at the bottom of the inclined structure, the second filter disc is fully retracted; when the connecting slide rod is at the top of the inclined structure, the second filter disc is fully extended.

5. The water immersion lithium extraction system for waste lithium battery negative electrode materials according to claim 4, characterized in that, The bottom of the tank is provided with at least three support legs.

6. The water immersion lithium extraction system for waste lithium battery negative electrode materials according to claim 4, characterized in that, The second separation component may not include the second drive element and the second drive shaft, and the bottom of the first drive shaft passes through the partition and is fixedly connected to the switching disk.

7. A method for resource-based recycling of waste lithium battery negative electrode materials, characterized in that, Includes the following steps: Step S1: Cut the waste lithium battery negative electrode into slices, evenly cover them with a eutectic NaOH-KOH mixture, place them in a crucible, and bake them in a tube furnace to obtain the baked product. Step S2: The baked product is mixed with deionized water and then injected into the waste lithium battery negative electrode material water immersion lithium extraction system as described in any one of claims 1-6. After stirring and filtration, graphite, copper foil and lithium-containing solution are obtained. Step S3: The lithium-containing solution is further purified by selectively adsorbing lithium through an ion sieve. Step S4: Wash the graphite with ultrapure water to remove residual alkali and fluorine compounds, and freeze-dry to obtain pure graphite; Step S5: Pure graphite and sodium hypochlorite are added to the solution of the organic dye Rhodamine B to degrade the organic dye Rhodamine B.

8. A method for resource recovery of waste lithium battery negative electrode materials according to claim 7, characterized in that, The specifications of the waste lithium battery negative electrode slices are 10mm×20mm.

9. A method for resource recovery of waste lithium battery negative electrode materials according to claim 7, characterized in that, The eutectic NaOH-KOH mixture was prepared by stirring sodium hydroxide and potassium hydroxide at a low speed in a 1:1 molar ratio.

10. A method for resource recovery of waste lithium battery negative electrode materials according to claim 7, characterized in that, The ion screening uses λ-MnO2.

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