Multistage collaborative extraction and separation device and method for waste lithium battery leaching solution

Abstract

The present application relates to the technical fields of hydrometallurgy and waste battery resource recovery, and discloses a multi-stage collaborative extraction and separation device and method for waste lithium battery leaching solution. The device comprises a support frame, a mixing assembly and a clarification assembly inside the support frame. A rotating main shaft with spiral blade groups and arc-shaped blades is arranged in the mixing cavity. A static turbine disperser and an annular cross-flow return pipe are arranged to form a circulating mixing. A conical sedimentation hopper, a detachable square filter screen, a circular ring overflow weir plate with a sawtooth-shaped notch and a heavy phase collection tank are arranged in the clarification cavity. The method comprises the steps of starting preparation, feeding, mixing and mass transfer, clarification and phase separation, phase liquid diversion, inter-stage transportation, residue discharge and stopping. The present application improves the extraction and separation efficiency by pre-dispersion of the static turbine disperser and deep shear of the blades, combined with annular cross-flow return for mass transfer enhancement. The conical sedimentation hopper and the filter screen realize continuous liquid-solid separation, and the overflow weir plate ensures uniform overflow of the heavy phase, which is suitable for fluctuations in the composition of the leaching solution.

Description

Technical Field

[0001] This invention relates to the fields of hydrometallurgy and waste battery resource recycling technology, and more specifically, to a multi-stage synergistic extraction and separation device and method for leachate from waste lithium batteries. Background Technology

[0002] Waste lithium batteries contain valuable metals such as lithium, cobalt, nickel, and manganese. Failure to effectively recycle them not only wastes resources but also pollutes the environment. Currently, the mainstream process for recovering valuable metals from waste lithium batteries is hydrometallurgy. Its core steps involve first discharging, dismantling, crushing, and roasting to obtain black powder, then acid leaching to obtain a leachate containing various metal ions, followed by liquid-liquid extraction to separate the metals sequentially. Multi-stage synergistic extraction, due to its ability to achieve the stepwise selective separation of lithium, cobalt, nickel, and manganese, is gradually becoming a research hotspot.

[0003] Existing multi-stage synergistic extraction and separation devices mostly adopt a multi-stage mixing and clarification tank series structure, that is, each stage has an independent mixing chamber and clarification chamber, relying on stirring to achieve two-phase mixing, and then settling and separating the phases in the clarification chamber. However, such devices have the following shortcomings when actually treating waste lithium battery leachate: First, the leachate source is complex, containing impurities such as aluminum, copper, iron, calcium, and magnesium, as well as fine solid particles, which are very easy to deposit at the bottom of the clarification chamber to form sludge. Traditional flat-bottom clarification chambers lack an effective continuous sludge discharge structure, requiring shutdown for cleaning, resulting in a short continuous operation cycle. Second, single-stage mixing chambers mostly use an axisymmetric flow field formed by a single stirring impeller, with a wide droplet size distribution and mass transfer dead zones, resulting in low extractant utilization. Often, more than twenty stages need to be connected in series to achieve the target separation rate, resulting in a long process and large equipment footprint. Third, inter-stage reflux mostly relies on gravity passive overflow, the reflux ratio is uncontrollable, and it is easy to cause short-circuit back mixing. Moreover, the heavy phase overflow and light phase discharge structure has poor adaptability to the fluctuation of leachate composition. The above-mentioned problems one, two, and three correspond to three technical pain points: sludge accumulation, low mass transfer efficiency, and severe backmixing, respectively. Existing devices cannot address these issues simultaneously. Therefore, there is an urgent need for a multi-stage synergistic extraction and separation device and method for waste lithium battery leachate that is compact in structure, has high mass transfer efficiency, can continuously discharge sludge, and is highly adaptable. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a multi-stage synergistic extraction and separation device and method for leachate from waste lithium batteries. This device can simultaneously solve the problems of sludge accumulation, low mass transfer efficiency, and severe backmixing under a purely mechanical structure, achieving efficient mixing and mass transfer, rapid clarification and phase separation, and continuous liquid-solid separation. It can adapt to fluctuations in leachate composition, shorten the number of extraction stages, and extend the continuous operation cycle.

[0005] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: The present invention is a multi-stage synergistic extraction and separation device for leachate from waste lithium batteries, including a support frame for supporting the structure, a mixing component installed inside the support frame, and a clarification component installed on top of the mixing component. The mixing assembly includes a mixing chamber installed on the lower surface of the inner wall of the support frame. A rotating main shaft is vertically installed in the middle of the lower surface of the inner wall of the mixing chamber. A static turbine disperser is installed in the lower middle part of the rotating main shaft. The static turbine disperser does not rotate with the rotating main shaft. A helical blade assembly is installed at the upper end of the static turbine disperser. An arc-shaped blade is inserted in the middle of the helical blade assembly. An aqueous phase feed pipe is horizontally connected to the lower left side of the mixing chamber. An organic phase feed pipe is connected to the lower right side of the mixing chamber, which is parallel to the aqueous phase feed pipe. An annular cross-flow return pipe is vertically installed at the rear end of the lower surface of the mixing chamber. The clarification assembly includes a clarification chamber installed at the upper end of the mixing chamber. A conical sludge hopper is vertically installed at the lower end of the inner wall of the clarification chamber. A detachable square filter screen is installed on the lower surface of the inner wall of the conical sludge hopper by bolts. A circular sludge discharge pipe is connected to the lower end of the side wall of the conical sludge hopper. An annular overflow weir plate is installed at the top of the conical sludge hopper. The upper surface of the annular overflow weir plate has serrated notches evenly spaced along the circumference. A heavy phase collection trough is coaxially sleeved on the outer ring surface of the annular overflow weir plate.

[0006] As a preferred embodiment of the present invention, a hanging controller is installed on one side of the support frame, and the static turbine diffuser has a disc-shaped structure with multiple upwardly inclined diffusion holes evenly spaced along its circumference on its upper surface. The hanging controller is used to centrally arrange the start-stop control components of the drive motor and control valve, thereby integrating the operating interface.

[0007] As a preferred embodiment of the present invention, a sealed bearing is installed at the lower end of the rotating spindle, a drive motor is vertically installed at the lower end of the sealed bearing, and a torque reducer is installed at the upper end of the rotating spindle. The sealed bearing ensures flexible rotation of the rotating spindle while achieving dynamic sealing at the bottom of the mixing chamber, and the torque reducer is used to adjust the rotational speed of the rotating spindle.

[0008] As a preferred embodiment of the present invention, the upper surface of the mixing chamber and the lower surface of the clarification chamber are coaxially fitted with matching flanges, which seal the mixing chamber and the clarification chamber together. The lower end of the annular cross-flow reflux pipe is sealed to the lower surface of the mixing chamber, and the upper end of the annular cross-flow reflux pipe is connected to the lower part of the clarification chamber. The lower end of the annular cross-flow reflux pipe, located inside the mixing chamber, is flared. The flared opening allows for uniform spraying of the reflux liquid, and the flanges ensure a detachable and sealed connection between the two chambers.

[0009] As a preferred embodiment of the present invention, the end of the aqueous feed pipe away from the mixing chamber is connected to a replenishing feed tank. The replenishing feed tank is used to store the aqueous leachate obtained after the powder from the grinding of waste lithium batteries is mixed and reacted with the leachate acid, thereby stabilizing the feed and buffering the fluctuation of the liquid.

[0010] As a preferred embodiment of the present invention, a control valve is installed on the surface of the circular slag discharge pipe to control the opening and closing of the slag discharge channel and realize periodic slag discharge.

[0011] As a preferred embodiment of the present invention, a sapphire glass observation window is embedded in the front sidewall of the clarification chamber, a light phase outlet pipe is connected to the upper left side of the outer wall of the clarification chamber, and a heavy phase outlet pipe is connected to the lower right side of the clarification chamber. The sapphire glass observation window is used to observe the position of the phase separation interface and the accumulation of sediment within the clarification chamber.

[0012] As a preferred embodiment of the present invention, the heavy phase collection tank has an annular structure, the heavy phase outlet pipe has a U-shaped structure, and the upper end of the heavy phase outlet pipe is sealed to the lower surface of the heavy phase collection tank. The annular heavy phase collection tank cooperates with the annular overflow weir plate to ensure that the heavy phase is uniformly collected circumferentially and then stably discharged through the U-shaped heavy phase outlet pipe.

[0013] As a preferred embodiment of the present invention, a U-shaped lifting frame is bolted to the upper surface of the inner wall of the annular overflow weir plate. A deep groove ball bearing is horizontally installed in the middle of the inner wall of the U-shaped lifting frame, and the lower end of the U-shaped lifting frame is mounted on the upper surface of the support frame via a suspension bracket. The U-shaped lifting frame transmits the lifting thrust to the overflow weir plate, and the deep groove ball bearing ensures that the overflow weir plate maintains a horizontal posture during the lifting process. A threaded sleeve is vertically installed on the suspension bracket in the front-back direction, and a threaded lifting rod is rotatably connected to the inner wall of the threaded sleeve via a thread. Axial displacement is generated by rotating the threaded lifting rod and the threaded sleeve, thereby driving the overflow weir plate to rise and fall.

[0014] As a preferred embodiment of the present invention, the method for multi-stage synergistic extraction and separation of leachate from waste lithium batteries using the aforementioned apparatus includes the following steps: Step 1, Start-up Preparation: Close the control valve on the circular slag discharge pipe, check that the detachable square filter screen is securely installed, and adjust the annular overflow weir plate to one-third to one-half of the height of the heavy phase layer in the clarification chamber by rotating the threaded lifting rod; after confirming that everything is correct, turn on the drive motor to make the rotating spindle rotate at a speed of 50 to 200 r / min.

[0015] Step 2, Feeding: Waste lithium battery leachate from the replenishment feed tank is continuously fed into the bottom of the mixing chamber of the first-stage co-extraction unit through the aqueous phase feed pipe, while extractant is continuously fed into the bottom of the same mixing chamber through the organic phase feed pipe, controlling the flow ratio of the aqueous phase to the organic phase.

[0016] Step 3, Mixing and Mass Transfer: The leachate, extractant, and liquid that flows back from the heavy phase zone at the bottom of the clarification chamber through the annular cross-flow reflux pipe converge at the bottom of the mixing chamber. They are then pre-dispersed through the diffusion holes of the static turbine disperser, and deeply sheared and mixed by the spiral blade assembly and the arc blades to form tiny droplets, thus completing the interphase transfer of metal ions.

[0017] Step 4, Clarification and Phase Separation: The mixed liquid overflows from the top of the mixing chamber into the clarification chamber, where it settles and separates under gravity. The lighter phase floats to the upper layer, while the heavier phase sinks to the lower layer. Solid particles slide down the inner wall of the conical sludge hopper to the bottom and are trapped by the removable square filter screen.

[0018] Step 5, Phase-liquid discharge: The light phase is collected through the annular gap between the outer edge of the annular overflow weir plate and the inner wall of the clarification chamber, and is discharged from the light phase outlet pipe at the upper left side of the clarification chamber; the heavy phase is turned over through the sawtooth notch on the upper surface of the annular overflow weir plate and enters the heavy phase collection tank, and is discharged from the U-shaped heavy phase outlet pipe.

[0019] Step 6, Interstage Conveying: The light phase outlet pipe of the first stage is connected to the organic phase feed pipe of the second stage, the heavy phase outlet pipe of the first stage is connected to the aqueous phase feed pipe of the second stage, and so on, to achieve multi-stage countercurrent extraction; adjacent stages are kept in liquid seal by U-shaped connecting pipes.

[0020] Step 7, Slag Discharge: Periodically open the control valve on the circular slag discharge pipe to discharge the solid particles trapped in the conical slag hopper; periodically loosen the bolts to remove the removable square filter screen for cleaning or replacement.

[0021] Step 8: Stop feeding, continue stirring for a period of time, then stop the drive motor, close all inlet and outlet valves, drain the residual liquid in the device, and disconnect the pipeline connection.

[0022] Compared with the prior art, this application has the following advantages: 1. To address the problems of mass transfer dead zone and low extractant utilization in existing single-stage flow fields, this invention utilizes a combination of a static turbine disperser, a helical blade assembly, and arc-shaped blades. The reflux liquid is first pre-dispersed through the diffusion holes of the static turbine disperser, and then deeply sheared and mixed by the rotating blades, forming a two-stage flow field of "static pre-dispersion - dynamic main shearing". This reduces the mass transfer dead zone, improves the single-stage mass transfer efficiency, and thus reduces the number of extraction stages required.

[0023] 2. In view of the problem that the intermediate reflux in the existing technology relies on gravity passive overflow and is prone to short-circuit back mixing, the present invention actively guides the liquid in the heavy phase zone at the bottom of the clarification chamber back to the bottom of the mixing chamber to form a cross-flow circulation through an annular cross-flow reflux pipe. The reflux path is controllable, avoiding short-circuit back mixing, further enhancing mass transfer and improving the utilization rate of extractant.

[0024] 3. In view of the problems of the existing technology that the clarification chamber sludge needs to be cleaned by stopping the machine and the continuous operation cycle is short, the present invention uses the combination of a conical sludge hopper and a detachable square filter screen to make solid particles slide down the inner wall of the cone and be intercepted by the filter screen. Sludge can be discharged and the filter screen can be replaced online at regular intervals, so as to achieve continuous liquid-solid separation and extend the continuous operation cycle.

[0025] 4. The present invention uses a circular overflow weir plate with a serrated notch to cooperate with a circular heavy phase collection tank, so that the heavy phase overflows uniformly and is stably discharged along the circumference. The height of the overflow weir plate is adjusted by a threaded lifting rod to adapt to the fluctuation of the leachate composition and ensure the stability of the phase separation interface.

[0026] 5. The present invention adjusts the annular ring through a purely mechanical combination of a U-shaped lifting frame, a deep groove ball bearing, a threaded sleeve, and a threaded lifting rod. Attached Figure Description

[0027] Figure 1 This is a three-dimensional schematic diagram of the multi-stage synergistic extraction and separation device and method for leachate from waste lithium batteries proposed in this invention; Figure 2 This is a cross-sectional structural schematic diagram of the multi-stage synergistic extraction and separation device and method for waste lithium battery leachate proposed in this invention; Figure 3 This is a magnified view of part A in the rabbit image; Figure 4 This is a schematic diagram of the surface structure of the rotating spindle of the multi-stage synergistic extraction and separation device and method for waste lithium battery leachate proposed in this invention. Figure 5 This is a schematic diagram of the spiral blade assembly and arc blade structure of the multi-stage synergistic extraction and separation device and method for waste lithium battery leachate proposed in this invention. Figure 6 This is a schematic diagram of the conical sedimentation hopper structure of the multi-stage synergistic extraction and separation device and method for leachate from waste lithium batteries proposed in this invention. Figure 7 This is a schematic diagram of the annular overflow weir plate structure of the multi-stage synergistic extraction and separation device and method for leachate from waste lithium batteries proposed in this invention. Figure 8 This is a schematic diagram of the surface structure of the mixing chamber in the multi-stage synergistic extraction and separation device and method for leachate from waste lithium batteries proposed in this invention. Figure 9 This is a schematic diagram of the surface structure of the clarification chamber of the multi-stage synergistic extraction and separation device and method for waste lithium battery leachate proposed in this invention.

[0028] In the attached diagram: 1. Support frame; 2. Mixing assembly; 201. Mixing chamber; 202. Rotating main shaft; 203. Static turbine disperser; 204. Helical blade assembly; 205. Arc-shaped blade; 208. Aqueous phase feed pipe; 209. Organic phase feed pipe; 210. Annular cross-flow reflux pipe; 211. Diffuser hole; 212. Sealed bearing; 213. Drive motor; 214. Torque reducer; 215. Flange; 3. Clarifying assembly; 301. Clarifying chamber; 302. Conical sludge hopper; 303. Removable square filter screen; 304. Circular slag discharge pipe; 305. Circular overflow weir plate; 306. Serrated notch; 307. Heavy phase collection tank; 308. Manual control valve; 309. Sapphire glass observation window; 310. Light phase outlet pipe; 311. Heavy phase outlet pipe; 312. U-shaped lifting frame; 313. Deep groove ball bearing; 314. Suspension bracket; 315. Threaded sleeve; 316. Threaded lifting rod; 317. Control valve; 4. Liquid replenishment feed tank; 5. Hanging controller. Detailed Implementation

[0029] The features and exemplary embodiments of various aspects of this application will now be described in detail. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain this application and are not configured to limit this application. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples of this application.

[0030] Example 1 Please see Figures 1 to 9 The present invention provides the following technical solution: a multi-stage synergistic extraction and separation device for leachate from waste lithium batteries, comprising a support frame 1, a mixing component 2 installed inside the support frame 1, and a clarification component 3 installed on top of the mixing component 2. The mixing component 2 and the clarification component 3 are arranged vertically, with the mixing component 2 located below and the clarification component 3 located above. The two are coaxially connected by a flange 213 to form a single-stage synergistic extraction unit. The entire machine is composed of N-stage synergistic extraction units connected in series along the flow direction of the liquid.

[0031] Specifically, the mixing component 2 includes a mixing chamber 201 installed on the lower surface of the inner wall of the support frame 1. The mixing chamber 201 is a rectangular cavity, vertically arranged, and a rotating main shaft 202 is vertically installed in the middle of the lower surface of its inner wall. A static turbine disperser 203 is installed in the lower middle part of the surface of the rotating main shaft 202. The static turbine disperser 203 is disc-shaped, horizontally arranged, and its outer edge is vertically welded to the inner wall of the mixing chamber 201. Its central through hole is in contact with the rotating main shaft 202, so the static turbine disperser 203 does not rotate with the rotating main shaft 202. Multiple inclined upward diffusion holes 206 are equidistantly opened along the circumference on the upper surface of the static turbine disperser 203. A helical blade assembly 204 is mounted on the upper end of the static turbine disperser 203. The helical blade assembly 204 is sleeved on the rotating main shaft 202 and rotates synchronously with the shaft. An arc-shaped blade 205 is inserted in the middle of the helical blade assembly 204, with the arc-shaped blade 205 located above the helical blade assembly 204. Together, they form an axial-radial combined stirring structure. The lower left side of the mixing chamber 201 is horizontally connected to an aqueous phase feed pipe 208, and the lower right side is horizontally connected to an organic phase feed pipe 209. A ring-shaped cross-flow reflux pipe 210 is vertically installed at the rear end of the lower surface. The ring-shaped cross-flow reflux pipe 210 is a circular pipe, and its lower end is sealed to the lower surface of the mixing chamber 201. One end inside the mixing chamber 201 is provided with a flared opening, and the upper end extends upward to the lower part of the clarification chamber 301. The end of the aqueous phase feed pipe 208 away from the mixing chamber 201 is connected to a replenishment feed tank 4, which is used to store the leachate from waste lithium batteries.

[0032] The clarification assembly 3 includes a clarification chamber 301 installed at the upper end of the mixing chamber 201. The clarification chamber 301 is a rectangular hollow cavity, vertically arranged, with a conical sludge hopper 302 vertically installed at the lower end of its inner wall. The conical sludge hopper 302 is an inverted frustum-shaped cone with an inner wall inclination angle of 60°. A removable square filter screen 303 is bolted to the lower surface of the inner wall of the conical sludge hopper 302. The square filter screen 303 has evenly distributed circular filter holes with a diameter of 0.5mm for easy disassembly and cleaning. A circular sludge discharge pipe 304 is connected to the lower end of the side wall of the conical sludge hopper 302, and a control valve 308 is installed on the surface of the sludge discharge pipe. A circular overflow weir plate 305 is installed on the top of the conical sludge hopper 302. The circular overflow weir plate 305 is vertically arranged, and its upper surface has serrated notches 306 evenly spaced along the circumference. An annular gap is left between its outer ring surface and the inner wall of the clarification chamber 301, which forms a light phase collection channel. A heavy phase collection tank 307 is coaxially fitted on the outer ring surface of the circular overflow weir plate 305. The heavy phase collection tank 307 is a ring structure, formed by the inner side of the circular overflow weir plate 305 and the inner bottom surface of the clarification chamber 301. The upper left side of the outer wall of the clarification chamber 301 is connected to a light phase outlet pipe 310, and the lower right side is connected to a heavy phase outlet pipe 311. The heavy phase outlet pipe 311 is a U-shaped structure, and its upper end is sealed to the lower surface of the heavy phase collection tank 307. A sapphire glass observation window 309 is embedded in the front side wall of the clarification chamber 301 for observing the phase separation interface inside the clarification chamber 301. A hanging controller 5 is installed on one side of the support frame 1. The hanging controller 5 is electrically connected to the drive motor 211 and the control valve 308 respectively, and is used to centrally control the start, stop and speed of the drive motor 211, as well as the opening and closing of the control valve 308.

[0033] The working principle of this invention is as follows: the leachate from waste lithium batteries enters the bottom of the mixing chamber 201 through the aqueous phase feed pipe 208, the extractant enters the bottom of the mixing chamber 201 through the organic phase feed pipe 209, and at the same time, the liquid in the heavy phase zone at the bottom of the clarification chamber 301 flows back to the bottom of the mixing chamber 201 through the annular cross-flow return pipe 210. The hanging controller 5 sends a command to start the drive motor 211, which drives the rotating main shaft 202 to rotate at a speed of 50 to 200 r / min via the torque reducer 212. This causes the spiral blade assembly 204 and the arc blade 205 to shear and mix the three-phase liquid. The reflux liquid is first cut and pre-dispersed by the diffusion holes 206 of the static turbine disperser 203, and then deeply sheared by the spiral blade assembly 204 and the arc blade 205 to form tiny droplets with a particle size of 0.1 to 0.5 mm. This allows lithium, cobalt, nickel, manganese and other ions to transfer from the aqueous phase to the organic phase, completing the interphase transfer of metal ions. The reflux effect of the annular cross-flow reflux pipe 210 causes the liquid to repeatedly undergo the cycle of "mixing-phase separation-remixing" to avoid short-circuit back mixing. The mixture overflows from the top of the mixing chamber 201 into the clarification chamber 301, where it settles and separates under gravity: the light phase (organic phase loaded with metal) floats to the upper layer, collects through the annular gap between the outer edge of the circular overflow weir plate 305 and the inner wall of the clarification chamber 301, and is discharged from the light phase outlet pipe 310; the heavy phase (extracted aqueous phase) sinks to the lower layer, overflows evenly through the sawtooth notch 306 into the heavy phase collection tank 307, and is discharged through the U-shaped heavy phase outlet pipe 311; solid particles slide down the 60° inclined inner wall of the conical slag hopper 302 to the bottom, are intercepted by the detachable square filter screen 303, and when slag discharge is required, the operator opens the control valve 308 through the hanging controller 5, and the solid slag is discharged through the circular slag discharge pipe 304. Rotating the threaded lifting rod 316 generates axial displacement through the engagement of the threaded sleeve 315 and the deep groove ball bearing 313, pushing the U-shaped lifting frame 312 and the annular overflow weir plate 305 to rise and fall. The deep groove ball bearing 313 ensures that the annular overflow weir plate 305 maintains a horizontal posture during the lifting process. The suspension bracket 314 supports the U-shaped lifting frame 312 on the upper surface of the support frame 1, thereby adjusting the height of the sawtooth notch 306 of the annular overflow weir plate 305 to accommodate liquids with different density ratios. The lower end of the rotating main shaft 202 is installed at the bottom of the mixing chamber 201 through a sealed bearing 207, which ensures flexible rotation while achieving dynamic sealing. The mixing chamber 201 and the clarification chamber 301 are sealed together by a flange 213, and the upper end of the annular cross-flow return pipe 210 is sealed together with the lower part of the clarification chamber 301. Operators can monitor the phase separation interface and sediment accumulation in real time through the sapphire glass observation window 309.

[0034] Example 2 Based on Specific Embodiment 1, the difference in this embodiment is that: a sealed bearing 207 is installed at the lower end of the rotating main shaft 202, and a drive motor 211 is vertically installed at the lower end of the sealed bearing 207; a torque reducer 212 is installed at the upper end of the rotating main shaft 202; the mixing chamber 201 and the clarifying chamber 301 are sealed together by a flange 213; the lower end of the annular cross-flow return pipe 210 is sealed to the lower surface of the mixing chamber 201, and its upper end is connected to the lower part of the clarifying chamber 301, with one end inside the mixing chamber 201 being flared. With this configuration, the drive motor 211 drives the rotating main shaft 202 to rotate stably via the torque reducer 212; the sealed bearing 207 balances dynamic sealing and rotational flexibility; the flange 213 ensures the seal at the connection between the mixing chamber 201 and the clarifying chamber 301 and is detachable; and the flared opening allows the liquid returning from the annular cross-flow return pipe 210 to be evenly sprayed below the static turbine disperser 203, enhancing the pre-dispersion effect.

[0035] Example 3 Based on specific embodiment two, the difference in this embodiment is that: a U-shaped lifting frame 312 is bolted to the upper surface of the inner wall of the annular overflow weir plate 305; a deep groove ball bearing 313 is horizontally installed in the middle of the inner wall of the U-shaped lifting frame 312; the lower end of the U-shaped lifting frame 312 is installed on the upper surface of the support frame 1 via a suspension bracket 314; a threaded sleeve 315 is vertically installed on the suspension bracket 314 in the front-back direction; a threaded lifting rod 316 is rotatably connected to the inner wall of the threaded sleeve 315 via threads; and the hanging controller 5 is electrically connected to the drive motor 211 and the control valve 308 respectively. With this configuration, by rotating the threaded lifting rod 316, axial displacement is generated through the threaded engagement between the threaded sleeve 315 and the deep groove ball bearing 313, which drives the U-shaped lifting frame 312 and the annular overflow weir plate 305 to rise and fall, thereby realizing continuous adjustment of the heavy phase liquid level to adapt to waste lithium battery leachate with different compositions and density ratios. The entire process requires no external power and is simple and reliable to operate.

[0036] The above are merely specific embodiments of the present invention, but the technical features of the present invention are not limited thereto. Any simple changes, equivalent substitutions, or modifications made based on the present invention to solve essentially the same technical problems and achieve essentially the same technical effects are all covered within the protection scope of the present invention.

Claims

1. A multi-stage synergistic extraction and separation device for leachate from waste lithium batteries, comprising a support frame (1) for supporting the structure, characterized in that: The supporting frame (1) is equipped with a mixing component (2), and a clarifying component (3) is installed on top of the mixing component (2); The mixing assembly (2) includes a mixing chamber (201) installed on the lower surface of the inner wall of the support frame (1). A rotating spindle (202) is vertically installed in the middle of the lower surface of the inner wall of the mixing chamber (201). A static turbine disperser (203) is installed in the lower middle part of the surface of the rotating spindle (202). The static turbine disperser (203) does not rotate with the rotating spindle (202). A spiral blade assembly (204) is installed at the upper end of the static turbine disperser (203). An arc-shaped blade (205) is inserted in the middle of the spiral blade assembly (204). A water phase feed pipe (208) is horizontally connected to the lower left side of the mixing chamber (201). An organic phase feed pipe (209) is connected to the lower right side of the mixing chamber (201) parallel to the water phase feed pipe (208). An annular cross-flow return pipe (210) is vertically installed at the rear end of the lower surface of the mixing chamber (201). The clarification component (3) includes a clarification chamber (301) installed at the upper end of the mixing chamber (201). A conical sludge hopper (302) is vertically installed at the lower end of the inner wall of the clarification chamber (301). A detachable square filter screen (303) is installed on the lower surface of the inner wall of the conical sludge hopper (302) by bolts. A circular slag discharge pipe (304) is connected to the lower end of the side wall of the conical sludge hopper (302). An annular overflow weir plate (305) is installed at the top of the conical sludge hopper (302). A sawtooth notch (306) is evenly spaced along the circumference on the upper surface of the annular overflow weir plate (305). A heavy phase collection trough (307) is coaxially sleeved on the outer ring surface of the annular overflow weir plate (305).

2. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: A hanging controller (5) is installed on one side of the support frame (1). The static turbine diffuser (203) is a disc-shaped structure with multiple upwardly inclined diffusion holes (211) evenly spaced along the circumference on its upper surface.

3. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: A sealed bearing (212) is installed at the lower end of the rotating spindle (202), a drive motor (213) is vertically installed at the lower end of the sealed bearing (212), and a torque reducer (214) is installed at the upper end of the rotating spindle (202).

4. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: The upper surface of the mixing chamber (201) and the lower surface of the clarification chamber (301) are both coaxially fitted with matching flanges (215), which seal the mixing chamber (201) and the clarification chamber (301) together. The lower end of the annular cross-flow reflux pipe (210) is sealed to the lower surface of the mixing chamber (201), and the upper end of the annular cross-flow reflux pipe (210) is connected to the lower part of the clarification chamber (301). The lower end of the annular cross-flow reflux pipe (210) and the end located inside the mixing chamber (201) is trumpet-shaped.

5. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: The end of the aqueous feed pipe (208) away from the mixing chamber (201) is connected to a replenishing feed tank (4), which is used to store the aqueous leachate obtained after the powder of the waste lithium battery after grinding is mixed and reacted with the leachate acid.

6. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: The circular slag discharge pipe (304) is equipped with a control valve (317) to control the opening and closing of the slag discharge channel and realize periodic slag discharge.

7. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: A sapphire glass observation window (309) is embedded in the front side wall of the clarification chamber (301). A light phase outlet pipe (310) is connected to the upper left side of the outer wall of the clarification chamber (301), and a heavy phase outlet pipe (311) is connected to the lower right side of the clarification chamber (301).

8. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: The heavy phase collection tank (307) has an annular structure, the heavy phase outlet pipe (311) has a U-shaped structure, and the upper end of the heavy phase outlet pipe (311) is sealed to the lower surface of the heavy phase collection tank (307).

9. The multi-stage synergistic extraction and separation device for leachate from waste lithium batteries according to claim 1, characterized in that: The inner wall of the annular overflow weir plate (305) is bolted to a U-shaped lifting frame (312). A deep groove ball bearing (313) is horizontally installed in the middle of the inner wall of the U-shaped lifting frame (312). The lower end of the U-shaped lifting frame (312) is installed on the upper surface of the support frame (1) through a suspension bracket (314). A threaded sleeve (315) is vertically installed on the suspension bracket (314) in the front-back direction. A threaded lifting rod (316) is rotatably connected to the inner wall of the threaded sleeve (315) through a thread.

10. A method for multi-stage synergistic extraction and separation of leachate from waste lithium batteries using the apparatus according to any one of claims 1 to 9, comprising the following steps: Step 1, Start-up preparation: Close the control valve (317) on the circular slag discharge pipe (304), check that the detachable square filter screen (303) is securely installed, and adjust the annular overflow weir plate (305) to one-third to one-half of the height of the heavy phase layer in the clarification chamber (301) by rotating the threaded lifting rod (316); after confirming that everything is correct, turn on the drive motor (213) to make the rotating spindle (202) rotate at a speed of 50 to 200 r / min; Step 2, Feeding: Waste lithium battery leachate from the replenishment feed tank (4) is continuously fed into the bottom of the mixing chamber (201) of the first-stage co-extraction unit through the aqueous phase feed pipe (208), while extractant is continuously fed into the bottom of the same mixing chamber (201) through the organic phase feed pipe (209), controlling the flow ratio of the aqueous phase to the organic phase. Step 3, Mixing and Mass Transfer: The leachate, extractant and liquid that flowed back from the bottom heavy phase zone of the clarification chamber (301) through the annular cross-flow reflux pipe (210) converge at the bottom of the mixing chamber (201). They are then pre-dispersed through the diffusion holes (211) of the static turbine disperser (203), and deeply sheared and mixed by the spiral blade group (204) and the arc blades (205) to form tiny droplets, thus completing the interphase transfer of metal ions. Step 4, Clarification and Phase Separation: The mixed liquid overflows from the top of the mixing chamber (201) into the clarification chamber (301), and settles and separates under gravity. The light phase floats to the upper layer, the heavy phase sinks to the lower layer, and the solid particles slide down the inner wall of the conical sludge hopper (302) to the bottom and are intercepted by the detachable square filter screen (303). Step 5, Phase liquid discharge: The light phase is collected through the annular gap between the outer edge of the annular overflow weir plate (305) and the inner wall of the clarification chamber (301), and is discharged from the light phase outlet pipe (310) at the upper left side of the clarification chamber (301); the heavy phase is turned over through the sawtooth notch (306) on the upper surface of the annular overflow weir plate (305) and enters the heavy phase collection tank (307), and is discharged from the U-shaped heavy phase outlet pipe (311); Step 6, Interstage Conveying: The light phase outlet pipe (310) of the first stage is connected to the organic phase feed pipe (209) of the second stage, and the heavy phase outlet pipe (311) of the first stage is connected to the aqueous phase feed pipe (208) of the second stage, and so on, to achieve multi-stage countercurrent extraction; the liquid seal between adjacent stages is maintained by U-shaped connecting pipes. Step 7, Slag Discharge: Periodically open the control valve (317) on the circular slag discharge pipe (304) to discharge the solid particles trapped in the conical slag hopper (302); periodically loosen the bolts to remove the removable square filter screen (303) for cleaning or replacement; Step 8, Stop: Stop feeding, continue stirring for a period of time, then stop the drive motor (213), close all inlet and outlet valves, drain the residual liquid in the device, and disconnect the pipeline connection.

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