Silver recovery treatment equipment for waste battery pieces

Abstract

The application discloses a silver extraction and recovery treatment equipment for waste battery pieces, which comprises a reaction kettle, a stirring unit and a solid-liquid separation unit. The stirring unit comprises a stirring shaft, a stirring paddle and a stirring power device. In one aspect, the application cooperates different suspension forces formed by partitioned jet flow and stirring stress formed by stirring to relatively suspend battery piece fragments in each partition, so that the liquid medicine fully contacts the surface of the battery piece fragments, eliminates static dead zones, avoids the formation of a passivation film covering the surface of the unseparated silver paste layer due to the left shift of chemical equilibrium, and greatly improves the stripping rate and quality of the silver paste. In another aspect, the application avoids hard friction and micro-cracks between the battery piece fragments based on the volume screening formed by layering, and the subsequent purification and separation of silver are more efficient. Meanwhile, the bridging and clogging are eliminated, and the phenomenon of stirring blockage and equipment wear caused by the battery piece fragments entering the gap between the paddle and the kettle wall is avoided by the cooperative suspension, so that the recovery efficiency and quality of the waste battery pieces are effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of solid waste treatment, specifically relating to a silver extraction and recycling device for waste battery cells. Background Technology

[0002] Currently, retired photovoltaic modules need to be recycled as solid waste to achieve resource recycling. This can not only alleviate the shortage of raw materials for photovoltaic equipment to a certain extent, but also effectively reduce environmental pollution (that is, recycling the solar cells in solid waste into useful raw materials to achieve resource recycling, while also effectively carrying out environmental governance and protecting the environment).

[0003] After the photovoltaic modules have undergone recycling steps such as the frame and front and back layers, the waste solar cells are then subjected to silver extraction and recycling. During this process, the waste solar cells need to be cut into fragments, which are then placed in a solution tank and subjected to microwave or ultrasonic treatment to accelerate the reaction and remove the silver paste layer from the silicon wafer surface. Solid sieving is then performed to separate the Ag particles from the silicon material. However, the following technical defects exist in this separation process: 1. Although silicon wafers are separated with the assistance of microwaves or ultrasound, the wafers are completely stacked together, preventing the reagent from making sufficient deep contact with the wafers. Furthermore, the wafers are tightly stacked in the middle and bottom of the container, creating numerous stagnant dead zones where the reagent flow is impeded, hindering silver dissolution reactions (such as Ag→Ag in nitric acid systems). + Ag produced + Ions and reaction byproducts cannot diffuse and migrate in time through natural convection within these dead zones, leading to localized Ag... + The rapid increase in concentration not only reversed the dissolution kinetics of the main reaction (shifting the chemical equilibrium to the left), causing a sharp decrease in the silver paste stripping rate in this region; simultaneously, at high Ag concentrations... + With residual Cl in the solution - or OH - Under the influence of this, insoluble silver chloride or silver oxide passivation film is easily precipitated and covers the surface of the unpeeled silver paste layer, forming a closed passivated state in which the reagent cannot enter and the product cannot exit, thus directly affecting the separation quality and efficiency of the silver paste layer. 2. Most silicon wafers are piled up at the discharge port of the material tank. Due to physical bridging and blockage in the discharge port area, the solid-liquid separation operation is frequently interrupted. At this time, manual intervention or backflushing device intervention is required, which seriously reduces the continuous operation throughput of the production line. At the same time, under the continuous ultrasonic vibration, the silicon wafers at the bottom of the discharge port are subjected to static pressure several times the weight of the upper layer, which aggravates the hard friction between wafers and the propagation of microcracks, generating a large amount of micron-sized silicon powder that is difficult to be intercepted by conventional screens. These silicon powders with high specific surface area are very easy to electrostatically adsorb or mechanically encapsulate with the stripped Ag particles to form silver-silicon agglomerates, which not only affects the purity of the final silver extraction, but also makes it difficult to separate silver and silicon.

[0004] Based on the aforementioned shortcomings, some manufacturers have attempted to alleviate these deficiencies through a combination of stirring and ultrasonic techniques, but the following drawbacks still exist: A) During the stirring process, due to the limitations of the reactor geometry (such as the bottom corners and near the discharge port), there are still localized areas of sluggish flow, especially the silicon wafer layer accumulated at the bottom, which the stirring blades cannot effectively reach. The chemical turnover rate in these areas remains extremely low. + The problems of local accumulation of ions and passivation film formation cannot be completely eliminated. At the same time, it is easy to cause blockage at the reactor outlet, which requires regular cleaning and affects the continuity of recycling multiple batches of waste solar cells, resulting in low recycling efficiency of waste solar cells. B) During rotation, the stirring blades directly collide and shear with the silicon wafers, especially in areas where silicon wafers are densely packed. This mechanical force exacerbates the breakage of the silicon wafers and the propagation of microcracks. At the same time, the fluid disturbance caused by stirring causes relative movement and collisions between the silicon wafers. Especially under high filling conditions, the hard friction between silicon wafers increases significantly. As a result, the micron-sized silicon powder generated by the breakage not only increases the difficulty of subsequent solid-liquid separation, but also forms silver-silicon agglomerates with the stripped Ag particles, which seriously affects the purity of silver extraction and leads to unsatisfactory recycling results of waste solar cells. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an improved silver extraction and recycling equipment for waste battery cells.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A waste solar cell silver extraction and recycling device includes a reaction vessel, a stirring unit, and a solid-liquid separation unit. The stirring unit includes a stirring shaft, stirring paddles, and a stirring power unit. The stirring shaft extends from the top to the bottom of the reaction vessel along its height direction. The stirring paddle includes multiple blades spaced apart on the stirring shaft along its extension direction. Each blade is disc-shaped and fits into the inner wall of the reaction vessel. The multiple blades divide the inner cavity of the reaction vessel into multiple reaction zones from top to bottom. Each blade has a through-hole mesh, and the mesh size gradually decreases from top to bottom. Solar cell fragments are screened into each reaction zone based on their volume. The stirring of the stirring paddle creates a force F on the axial and / or radial directions of the stirring shaft between the solar cell fragments in each reaction zone. 搅 The recycling and processing equipment also includes injecting fluid into each reaction zone to simultaneously generate an upward levitation force F on the battery cell fragments. 浮 The suspended unit, in which multiple reaction zones of F 浮 It decreases in size from top to bottom, and at F 搅 and F 浮 With the cooperation of the system, the battery cell fragments in each reaction zone are suspended in relative order.

[0007] According to a specific embodiment and preferred aspect of the invention, the suspension unit is disposed on the stirring unit and rotates synchronously with the stirring unit to form a kinematic cooperation. Here, it is ensured that F 搅 and F 浮 The precise connection between them forms a collaboration, further enhancing the suspension effect of the battery cells in each reaction zone.

[0008] According to another specific embodiment and preferred aspect of the invention, a top-open fluid channel is formed inside the stirring shaft, and the suspension unit includes a plurality of nozzles mounted on the stirring shaft and distributed in each reaction zone, an adapter that is rotatably and sealingly connected to the top of the stirring shaft, and a fluid supply assembly, wherein the fluid passes through the adapter and enters the fluid channel, and is sprayed from the nozzles to the reaction zones to form a suspension force.

[0009] Preferably, the fluid flow rate from multiple nozzles gradually decreases from top to bottom; and / or, each nozzle is positioned on the bottom stirring shaft of its corresponding reaction zone, and the angle formed by each nozzle and the stirring shaft is an acute angle; and / or, the centerline of the nozzle orifice intersects the sidewall of the reactor in its respective reaction zone. Here, based on the volume distribution of the battery cell fragments in each reaction zone, the variation in fluid flow rate formed by multiple nozzles is used to suspend the battery cell fragments in each layer, while simultaneously reducing the probability of battery cell fragments from the lower reaction zone entering the upper reaction zone.

[0010] According to another specific embodiment and preferred aspect of the invention, each blade includes a blade body horizontally and fixedly connected to the stirring shaft, and a retaining ring extending upward from the edge of the blade body. As the stirring shaft rotates, the blade body generates a force F acting radially on the stirring shaft. 搅 Here, by cooperating with the impeller body and the baffle ring, the probability of battery cells near the edge falling into the gap between the impeller body and the inner wall of the reactor and causing jamming can be reduced during agitation. This also ensures that battery cell fragments near the edge can float axially upwards under the radial obstruction of the baffle ring and enter the reactor. 浮 Scope of application.

[0011] Preferably, each of the blades is detachably connected to the stirring shaft. This facilitates the unloading operation.

[0012] According to another specific embodiment and preferred aspect of the invention, the inner cavity of the reactor includes an upper cavity and a lower cavity that extend vertically through each other. The upper cavity is cylindrical, and the lower cavity is conical, gradually narrowing from top to bottom, and has a discharge port that can be opened or closed from the bottom. Multiple impellers are distributed within the upper cavity. This enhances the stirring effect of the battery cells within the upper cavity.

[0013] According to another specific embodiment and preferred aspect of the present invention, a discharge port is formed at the bottom of the reactor, and the solid-liquid separation unit includes a multi-stage filtration assembly arranged below the discharge port and sequentially from top to bottom. During separation, the multi-stage filtration assembly filters the silver-containing liquid discharged from the discharge port layer by layer from top to bottom. Here, fine impurities that cannot be screened by the upper impeller in the silver-containing liquid are further filtered out, ensuring the purity of the subsequently extracted silver powder.

[0014] Preferably, each filter assembly includes a filter tank with filter holes and a drain funnel disposed below the filter tank, wherein the pore size of the filter holes in the multi-stage filter tank gradually decreases from top to bottom.

[0015] In addition, the recycling equipment also includes a vibration unit, which comprises multiple ultrasonic vibrators spaced circumferentially around the reactor.

[0016] Due to the implementation of the above technical solutions, the present invention has the following advantages compared with the prior art: In existing technologies, due to limitations imposed by the reactor's geometry (such as the bottom corners and near the discharge port), localized areas of sluggish flow still exist during the stirring process. This is especially true for the silicon wafer layer accumulated at the bottom, which the stirring blades cannot effectively reach. Consequently, the chemical turnover rate in these areas remains extremely low. +The problems of local ion accumulation and passivation film formation cannot be fundamentally eliminated, and they can easily cause blockage at the reactor outlet, requiring regular cleaning. This affects the continuity of recycling multiple batches of waste solar cells, resulting in low recycling efficiency. During the rotation of the stirring blades, there is direct collision and shearing action with the silicon wafers, especially in areas where silicon wafers are densely packed. This mechanical force exacerbates the breakage of silicon wafers and the propagation of microcracks. At the same time, the fluid disturbance caused by stirring causes relative movement and collisions between silicon wafers. Especially under high filling conditions, the hard friction between silicon wafers increases significantly. As a result, the micron-sized silicon powder generated by the breakage not only increases the difficulty of subsequent solid-liquid separation, but also forms silver-silicon agglomerates with the stripped Ag particles, which seriously affects the purity of silver extraction, resulting in unsatisfactory recycling effect of waste solar cells. This invention provides a holistic structural design for a waste battery cell silver extraction and recycling equipment, cleverly addressing the shortcomings and defects of existing technologies. Using this recycling equipment, waste battery cell fragments and processing solutions are added to a reaction vessel. Multiple impellers, spaced apart along the stirring shaft, sieve the waste battery cell fragments into different reaction zones based on their volume. The stirring action of the impellers creates a force F acting on the battery cells in each reaction zone along the axial and / or radial directions of the stirring shaft. 搅 Fluid is injected from the suspension unit into each reaction zone to simultaneously generate an upward levitation force F on the battery cells. 浮 F in multiple reaction zones 浮 It decreases in size from top to bottom, and at F 搅 and F 浮 With the cooperation of various methods, the solar cells in each reaction zone are relatively suspended. Therefore, compared with the prior art, this invention, on the one hand, is based on the cooperation of the different suspension forces formed by the zoned jets and the stirring stress formed by the stirring, to relatively suspend the solar cell fragments in each zone. The liquid medicine fully contacts the surface of the solar cell fragments, eliminating dead zones and preventing the formation of a passivation film covering the surface of the unseparated silver paste layer by the leftward shift of chemical equilibrium, thereby significantly improving the silver paste stripping rate and quality. On the other hand, based on the volumetric sieving formed by the layering, hard friction and microcracks between solar cell fragments are avoided, reducing the formation rate of silver-silicon agglomerates. The subsequent purification and separation of silver are more efficient, while eliminating bridging blockage. Moreover, the cooperative suspension can also prevent solar cell fragments from entering the gap between the impeller and the reactor wall, causing stirring jamming and equipment wear, effectively improving the recycling efficiency and recycling quality of waste solar cells. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural diagram of the waste battery cell silver extraction and recycling equipment of the present invention. Figure 2 for Figure 1 Front view diagram (partially omitted); Figure 3 for Figure 2Schematic diagram of the sectional view along the central AA direction; Figure 4 This is a three-dimensional structural diagram of the waste battery cell silver extraction and recycling equipment of the present invention (excluding the outer shell, vibration unit, and stirring power unit). Figure 5 for Figure 4 A structural decomposition diagram; Figure 6 for Figure 3 Enlarged schematic diagram of the structure of the stirring shaft and stirring paddle; Wherein: 1. Reactor; q0, Upper cavity; k0, Feed port; q1, Lower cavity; k1, Discharge port; f, Valve; q2, Reaction zone; 2. Stirring unit; 20. Stirring shaft; 200. Fluid channel; 21. Stirring paddle; 210. Paddle blade; a0. Paddle blade body; k2. Mesh; a1. Retaining ring; 22. Stirring power unit; 3. Suspension unit; 30. Nozzle; 31. Adapter; g. Liquid delivery pipeline; 4. Solid-liquid separation unit; 40. Filter assembly; 400. Filter tank; k3. Filter hole; 401. Drainage funnel; 5. Vibration unit; 50. Ultrasonic vibrator. Detailed Implementation

[0018] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0019] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0020] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0021] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0023] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0024] like Figures 1 to 6 As shown, the waste battery cell silver extraction and recycling equipment involved in this embodiment includes a reaction vessel 1, a stirring unit 2, a suspension unit 3, a solid-liquid separation unit 4, a vibration unit 5, and a battery cell crushing unit.

[0025] Specifically, the inner cavity of the reactor 1 includes an upper cavity q0 and a lower cavity q1 that run vertically through each other. The upper cavity q0 is cylindrical and has a feeding port k0 formed from the top. The battery cell fragments cut by the battery cell crushing unit are fed into the inner cavity of the reactor 1 through the feeding port k0. The lower cavity q1 is conical and gradually narrows from top to bottom and has a discharge port k1 that can be opened or closed from the bottom. A valve f is provided at the discharge port k1 to control the opening or closing of the discharge port k1. The valve f is a solenoid valve.

[0026] In this example, the stirring unit 2 includes a stirring shaft 20, a stirring paddle 21, and a stirring power unit 22 that drives the stirring shaft 20 to rotate around its own centerline. The stirring shaft 20 extends from the top to the bottom of the reactor 1 along its height direction. The stirring paddle 21 includes multiple blades 210 fixed on the stirring shaft 20 and spaced apart along the extension direction of the stirring shaft 20. Each blade 210 is a disc-shaped part that fits with the inner wall of the reactor 1 with a clearance. The multiple blades 210 divide the inner cavity of the reactor 1 into multiple reaction zones q2 from top to bottom. The upper part has a mesh k2 that runs vertically through it. The mesh k2 on the multiple blades 210 gradually decreases in size from top to bottom, and the battery cell fragments are screened into each reaction zone q2 based on their volume. The stirring power unit 22 is a motor. The output shaft of the motor is offset from the stirring shaft 20 and is driven by a gear set or a transmission belt (not shown in the figure, but it is not difficult to imagine) to drive the stirring shaft 20 to rotate around its own center line. The stirring of the stirring blades 21 forms a force F on the axial and / or radial directions of the stirring shaft 20 to form the battery cell fragments in each reaction zone q2. 搅 Suspension unit 3 synchronously generates an upward levitation force F on the battery cell fragments in each reaction zone q2. 浮 F in multiple reaction zones 浮 It decreases in size from top to bottom, and at F 搅 and F 浮 With the cooperation of the parties, the battery cell fragments in each reaction zone q2 are relatively suspended.

[0027] In some specific embodiments, there are two blades 210, both distributed within the upper cavity q0. This enhances the stirring effect of the battery cell fragments within the upper cavity.

[0028] Each impeller 210 includes an impeller body a0 horizontally and fixedly connected to the stirring shaft 20, and a retaining ring a1 extending upward from the edge of the impeller body a0. As the stirring shaft 20 rotates, the impeller body a0 generates a force F acting radially on the stirring shaft 20. 搅 Here, by cooperating with the impeller body and the baffle ring, the probability of battery cell fragments near the edge falling into the gap between the impeller body and the inner wall of the reactor and causing material jamming can be reduced during agitation. This also ensures that battery cells near the edge can float axially upwards under the radial obstruction of the baffle ring to enter the reactor. 浮 Scope of application.

[0029] For ease of implementation, the suspension unit 3 is mounted on the stirring unit 2 and rotates synchronously with it to form a motion cooperative mechanism. Here, it is ensured that F... 搅 and F 浮 The precise connection between them forms a collaboration, further enhancing the suspension effect of the battery cells in each reaction zone.

[0030] In some specific embodiments, a top-open fluid channel 200 is formed within the stirring shaft 20. The suspension unit 3 includes multiple nozzles 30 mounted on the stirring shaft 20 and distributed in each reaction zone q2, an adapter 31 rotatably and sealingly connected to the top of the stirring shaft 20, and a fluid supply assembly (not shown in the figure, but easily understood) connected to the adapter 31 and communicating with the fluid channel 200. The fluid supply assembly guides fluid through the adapter 31 into the fluid channel 200, and then sprays it from the nozzles 30 towards the reaction zones q2 to create a suspending force. In this embodiment, the fluid provided by the fluid supply assembly 32 can be a conventional reaction solution used in silver extraction processes. The injection speed of the fluid can be determined according to the actual operating conditions of the reactor, especially considering the nozzle installation angle, the composition of the reaction solution, and the internal pressure of the reactor, to select an appropriate injection speed to reduce bubbles generated at the moment of fluid ejection. In other specific embodiments, the fluid provided by the fluid supply assembly 32 can also be an antifoaming agent that does not chemically react with the battery cell fragments and the reaction solution, to create a suspending force and simultaneously suppress the formation of bubbles in the reaction solution. By reducing or suppressing the formation of bubbles in the reaction solution, it is ensured that the battery cell fragments are completely immersed and fully contact the reaction solution, thereby reducing bubble interference and improving reaction efficiency and silver paste stripping rate.

[0031] It should be noted that when feeding materials, there is usually a certain space above the liquid level in the reactor, and the top of the reactor has an exhaust port. Therefore, during a silver extraction process, a certain amount of fluid is allowed to be injected into the reactor. This process can be either continuous or intermittent fluid injection.

[0032] In some specific embodiments, the adapter 31 uses an existing rotary joint; the fluid supply assembly is connected to the adapter 31 via any conventional liquid delivery pipe g.

[0033] At the same time, the fluid flow rate formed by multiple nozzles 30 gradually decreases from top to bottom to adjust F. 浮The nozzles 30 gradually decrease in size from top to bottom, meaning their orifice sizes decrease progressively. Each nozzle 30 can be circular, elliptical, or slit-shaped. When slit-shaped, each nozzle 30 can eject a jet that diffuses circumferentially around the stirring shaft 20. Each nozzle 30 is positioned on the bottom stirring shaft 20 of its corresponding reaction zone q2, forming an acute angle with the stirring shaft 20. The nozzles 30 can be aligned vertically or staggered vertically. Each reaction zone can have one nozzle 30 or multiple nozzles arranged circumferentially around the stirring shaft. The centerline of each nozzle 30's orifice intersects the sidewall of the reactor 1 in its respective reaction zone q2. Here, based on the volume distribution of the battery cell fragments in each reaction zone, the fluid flow rate variation created by the multiple nozzles suspends the battery cells in each layer, while simultaneously reducing the probability of battery cells from lower reaction zones entering upper reaction zones.

[0034] In this example, the solid-liquid separation unit 4 includes a multi-stage filtration assembly 40 arranged sequentially from top to bottom below the discharge port k1. During separation, the multi-stage filtration assembly 40 filters the silver-containing liquid discharged from the discharge port k1 layer by layer from top to bottom. Here, fine impurities that cannot be screened by the upper blades in the silver-containing liquid are further filtered out to ensure the purity of the subsequently extracted silver powder.

[0035] In some specific embodiments, each filter assembly 40 includes a filter tank 400 with filter holes k3 and a drain funnel 401 disposed below the filter tank 400. The diameter of the filter holes k3 in the multi-stage filter tank 400 gradually decreases from top to bottom. After being filtered by the multi-stage filter tank, the silver-containing liquid is discharged and collected through the drain funnel 401 at the bottom. Each stage of the filter tank 400 adopts a drawer-type design so that it can be pulled out or pushed back in.

[0036] In addition, the vibration unit 5 includes multiple ultrasonic vibrators 50 arranged circumferentially around the reactor 1. The multiple ultrasonic vibrators 50 synchronously generate ultrasonic waves to vibrate the cell fragments in each reaction zone, so as to assist the silver paste peeling off the surface of the cell and further improve the silver paste collection rate.

[0037] In summary, after adopting this recycling and processing equipment, the discharge port at the bottom of the reactor is closed, and the waste battery cell fragments and processing solution are added to the reactor. Multiple blades spaced along the extension direction of the stirring shaft separate the waste battery cell fragments into different reaction zones based on their volume. The stirring power unit is activated to drive the stirring shaft to rotate. The stirring of the blades creates a radial force F on the battery cells in each reaction zone along the stirring shaft. 搅 Multiple nozzles arranged axially along the stirring shaft in the suspension unit inject fluid into each reaction zone to simultaneously generate an upward levitation force F on the solar cells in each reaction zone. 浮 F in multiple reaction zones浮 It decreases in size from top to bottom, and at F 搅 and F 浮 With the cooperation of the equipment, the battery cells in each reaction zone are suspended relative to each other to ensure that the battery cells are in full contact with the liquid. At the same time, multiple ultrasonic vibrators are used to vibrate the waste battery cell fragments to help peel off the silver paste from the surface of the battery cells. Finally, the discharge port at the bottom of the reactor is opened to discharge the silver-containing liquid in the reactor downward. The silver-containing liquid discharged from the discharge port is filtered layer by layer from top to bottom through a multi-stage filtration assembly to further filter out the fine impurities in the silver-containing liquid that cannot be screened by the upper blades.

[0038] Therefore, compared with the prior art, this invention, on the one hand, is based on the cooperation of the different suspension forces formed by the partitioned jet and the stirring stress formed by the stirring, to relatively suspend the solar cells in each partition, ensuring that the liquid fully contacts the surface of the solar cells, eliminating dead zones, and preventing the formation of a passivation film covering the surface of the unseparated silver paste layer by the leftward shift of chemical equilibrium, thus significantly improving the silver paste stripping rate and quality; on the other hand, based on the volumetric sieving formed by the layering, it avoids hard friction and microcracks between solar cells, reduces the formation rate of silver-silicon agglomerates, and makes the subsequent silver purification and separation more efficient, while eliminating bridging blockage. Moreover, the cooperative suspension can also prevent solar cells entering the gap between the impeller and the vessel wall from causing stirring jamming and equipment wear; thirdly, the synchronous rotation of the suspension unit and the stirring unit forms a motion cooperation to ensure F 搅 and F 浮 The precise connection between them forms a collaboration, further improving the suspension effect of the solar cells in each reaction zone; fourthly, based on the volume distribution of the solar cells in each reaction zone, the fluid flow rate changes formed by multiple nozzles are used to suspend the solar cells in each layer, while simultaneously reducing the probability of solar cells from the lower reaction zone entering the upper reaction zone; fifthly, through the cooperation of the impeller body and the baffle ring, the probability of solar cells near the edge falling into the gap between the impeller body and the inner wall of the reactor and causing material jamming can be reduced during agitation, and it is ensured that solar cells near the edge can float axially upward under the radial obstruction of the baffle ring to contact F. 浮 Sixthly, it enhances the stirring effect of the battery cells in the upper chamber; seventhly, it further filters out fine impurities in the silver-containing liquid that cannot be screened by the upper blades, ensuring the purity of the extracted silver powder.

[0039] The present invention has been described in detail above, with the aim of enabling those skilled in the art to understand and implement the invention. However, this description should not be construed as limiting the scope of protection of the invention. All equivalent changes or modifications made in accordance with the spirit and essence of the invention should be included within the scope of protection of the invention.

Claims

1. A waste battery cell silver extraction and recycling equipment, comprising a reaction vessel, a stirring unit, and a solid-liquid separation unit, wherein the stirring unit includes a stirring shaft, a stirring paddle, and a stirring power unit, wherein the stirring shaft extends from the top to the bottom of the reaction vessel along its height direction, characterized in that... The stirring paddle includes multiple blades spaced apart on a stirring shaft, each blade being a disc-shaped part that fits snugly against the inner wall of the reactor. The blades divide the reactor cavity into multiple reaction zones from top to bottom, and each blade has a through-hole mesh. The mesh size decreases progressively from top to bottom, allowing the battery cell fragments to be sieved into the respective reaction zones based on their size. The stirring action of the paddle creates a force F on the axial and / or radial directions of the stirring shaft, forming the battery cell fragments in each reaction zone. 搅 The recycling and processing equipment also includes injecting fluid into each reaction zone to simultaneously generate an upward levitation force F on the battery cell fragments. 浮 The suspended unit, in which multiple reaction zones of F 浮 It decreases in size from top to bottom, and at F 搅 and F 浮 With the cooperation of the system, the battery cell fragments in each reaction zone are suspended in relative order.

2. The waste battery cell silver extraction and recycling equipment according to claim 1, characterized in that, The suspension unit is mounted on the stirring unit and rotates synchronously with the stirring unit to form a motion collaboration.

3. The waste battery cell silver extraction and recycling equipment according to claim 1, characterized in that, A fluid channel with an open top is formed inside the stirring shaft. The suspension unit includes multiple nozzles installed on the stirring shaft and distributed in each reaction zone, an adapter that is rotatably and sealingly connected to the top of the stirring shaft, and a fluid supply assembly. The fluid passes through the adapter and enters the fluid channel, and is then sprayed from the nozzles to the reaction zones to form a suspension force.

4. The waste battery cell silver extraction and recycling equipment according to claim 3, characterized in that, The multiple nozzles form a fluid flow rate that gradually decreases from top to bottom; and / or, each nozzle is positioned on the bottom stirring shaft of the corresponding reaction zone, and the angle formed by each nozzle and the stirring shaft is an acute angle; and / or, the centerline of the nozzle orifice intersects with the side wall of the reactor in the reaction zone.

5. The waste battery cell silver extraction and recycling equipment according to claim 1, characterized in that, Each of the impellers includes an impeller body horizontally and fixedly connected to the stirring shaft, and a retaining ring extending upward from the edge of the impeller body. As the stirring shaft rotates, the impeller body generates a force F acting radially on the stirring shaft. 搅 .

6. The waste battery cell silver extraction and recycling equipment according to claim 1, characterized in that, Each of the blades is detachably connected to the stirring shaft.

7. The waste battery cell silver extraction and recycling equipment according to claim 1, characterized in that, The reactor's internal cavity includes an upper cavity and a lower cavity that run vertically through each other. The upper cavity is cylindrical, and the lower cavity is conical, gradually narrowing from top to bottom, and has a discharge port that can be opened or closed from the bottom. The multiple blades are distributed within the upper cavity.

8. The waste battery cell silver extraction and recycling equipment according to claim 1, characterized in that, The bottom of the reactor has a discharge port, and the solid-liquid separation unit includes a multi-stage filtration assembly arranged below the discharge port and arranged sequentially from top to bottom. During separation, the multi-stage filtration assembly filters the silver-containing liquid discharged from the discharge port layer by layer from top to bottom.

9. The waste battery cell silver extraction and recycling equipment according to claim 8, characterized in that, Each of the filter components includes a filter tank with filter holes and a drain funnel disposed below the filter tank, wherein the pore size of the filter holes in the multi-stage filter tank gradually decreases from top to bottom.

10. The waste battery cell silver extraction and recycling equipment according to claim 1, characterized in that, The recycling and processing equipment also includes a vibration unit, which comprises a plurality of ultrasonic vibrators arranged circumferentially around the reaction vessel.

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