A waste ternary lithium battery recycling and sorting device and its use method

Abstract

The present invention relates to the field of lithium battery recycling technology, and in particular to a waste ternary lithium battery recycling and sorting device and its use method. Among them, a waste ternary lithium battery recycling and sorting device includes: a crushing module; a roasting module, connected to the downstream of the crushing module, used to carry out reducing gas suspension roasting of black powder to decompose organic matter; a multi-stage magnetic separation module; an acid leaching purification module; a graphite processing module, used to purify and grade the sorted graphite; a circulation module; wherein the crushing module, roasting module, multi-stage magnetic separation module, acid leaching purification module, graphite processing module and circulation module are connected in the order of material flow, and the output of the front module is the input of the rear module. Through the organic connection of these modules, not only the efficient recycling of waste ternary lithium batteries is guaranteed, but also the goal of green environmental protection is achieved while ensuring resource utilization, thereby improving the overall economic and environmental benefits.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery recycling, and in particular to a waste ternary lithium battery recycling and sorting device and a use method thereof. Background Art

[0002] There are currently several technical barriers in the field of resource recycling of ternary lithium batteries. These barriers are rooted in the deep contradiction between the intrinsic properties of the materials and the process coupling mechanism, which are specifically manifested as follows:

[0003] When existing crushing systems achieve phase dissociation of multiphase complexes (metal / black powder / organic components), improper control of interfacial energy often leads to non-selective intercalation of metal particles and active materials. For example, during traditional mechanical deconstruction, the static matching mode of shear force field and screening parameters cannot adapt to the heterogeneity of battery casing materials (such as aluminum-plastic film / steel shell), causing the proportion of residual heterogeneous elements such as Fe and Cu in the black powder to exceed the critical threshold (>5wt%), resulting in a catalytic poisoning effect on subsequent thermochemical reactions.

[0004] In addition, in the current calcination process, the thermal cracking kinetics of organic binders (such as PVDF and CMC) have a nonlinear response relationship with the reducing atmosphere, resulting in the residual carbon-based skeleton in the cracking product forming an ion migration barrier, which significantly inhibits the lattice reconstruction activity of the target metal oxide. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a waste ternary lithium battery recycling and sorting device and a method for using the same.

[0006] The technical solutions provided by the embodiments of the present invention are as follows:

[0007] An embodiment of the present invention provides a waste ternary lithium battery recycling and sorting device, comprising:

[0008] Crushing module, used to discharge, disassemble and crush used ternary lithium batteries, and separate black powder and metal particles;

[0009] The roasting module is connected to the downstream of the crushing module and is used to perform reducing gas suspension roasting on the black powder to decompose organic matter;

[0010] Multi-stage magnetic separation module, including a superconducting magnetic separator and hydrocyclone connected in series, and a high-gradient magnetic separator, for separating magnetic metal oxides, graphite and metallic impurities;

[0011] Acid leaching and purification module, including two-stage reaction tanks, used for preferential leaching of lithium and selective leaching of nickel, cobalt and manganese respectively;

[0012] Graphite processing module, used to purify and grade the sorted graphite;

[0013] a circulation module, comprising a precipitation device and a solution reflux pipeline connected to the acid leaching purification module, for recovering the metal solution and circulating the unsaturated liquid;

[0014] The crushing module, roasting module, multi-stage magnetic separation module, acid leaching purification module, graphite processing module and circulation module are connected in the order of material flow, and the output of the front module is the input of the rear module.

[0015] Accordingly, an embodiment of the present invention further provides a method for using a waste ternary lithium battery recycling and sorting device, comprising the following steps:

[0016] Step 1: The discharged battery modules are crushed by a crushing roller. The black powder particle size distribution is monitored in real time by a vibrating screening mechanism, and the screen parameters are dynamically adjusted to separate the black powder and metal particles. The black powder is then transported to a suspension roasting furnace. A reducing gas is introduced, and the gas mixing ratio and roasting temperature are dynamically adjusted based on the detection results of the binder type in the black powder to keep the material in a suspended state and decompose organic matter.

[0017] Step 2: After calcination, the material is wet-grinded to the target particle size and then enters a superconducting magnetic separator to separate magnetic metal oxides and non-magnetic products based on the magnetic characteristics of the material. The non-magnetic products are graded by density in a hydrocyclone, and the light phase products are passed through a high-gradient magnetic separator for a second time to remove residual metal impurities.

[0018] Step 3: After the magnetic metal oxide is mixed with the non-magnetic product treated in step 2, an organic acid and a complexing agent are dynamically added based on real-time monitoring by a pH sensor to preferentially leach lithium and complex metal impurities to obtain acid leaching residue, completing the first stage of acid leaching. The acid leaching residue is dynamically controlled by the amount of reducing agent injected under high temperature conditions to selectively leach nickel, cobalt and manganese, ultimately obtaining residual graphite, completing the second stage of acid leaching;

[0019] Step 4: The graphite obtained in step 3 is subjected to multi-stage countercurrent washing until the conductivity meets the standard and then dried. The dried graphite is classified according to particle size and then carbonized and repaired and lubricant compounded;

[0020] Step 5: The liquid after the acid leaching is precipitated with sodium carbonate to form lithium carbonate. The remaining unsaturated solution is refluxed to the wet grinding process through a proportional integral valve controlled by a conductivity sensor to complete lithium recovery.

[0021] The second-stage acid leaching liquid passes through a three-stage pH adjustment device to precipitate Fe or Al at pH = 4.3 ± 0.1, Ni or Co at pH = 9.0 ± 0.2, and Mn at pH = 11.0 ± 0.3, thereby completing the recovery of the ternary metals.

[0022] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0023] This invention demonstrates significant benefits in technological innovation, resource utilization, and environmental protection. First, through modular collaborative process design, it achieves efficient metal resource recovery and optimized material properties: the crushing module uses dynamic adjustment of the crushing roller spacing and the inclination angle of the vibrating screen, combined with real-time monitoring of metal purity using an X-ray fluorescence spectrometer, achieving a copper and aluminum particle separation efficiency exceeding 98.5%. The roasting module uses an infrared spectrometer to detect the binder type and precisely control the reducing gas ratio and temperature zoning, increasing the organic matter decomposition rate to 99.2% while reducing harmful emissions from pyrolysis exhaust by 90%. Second, innovative sorting and purification technologies significantly improve resource utilization: the superconducting magnetic separator, through the synergistic effect of three-layer grid-type magnetic pole plates and a high-gradient magnetic separation medium matrix, achieves a nickel, cobalt, and manganese oxide recovery rate exceeding 98.5% and graphite purity to 99.3%. The two-stage acid leaching tank utilizes a differentiated stirring structure and dynamic pH control to achieve a lithium leaching rate of ≥95% and a nickel, cobalt, and manganese selective leaching rate of >99%, reducing acid consumption by 40% compared to traditional processes. In addition, the closed-loop resource circulation system significantly reduces the environmental burden: the circulation module increases the reuse rate of unsaturated solution to 85% and reduces wastewater discharge by 70%; the graphite treatment module uses a combined process of countercurrent water washing and flash drying to reduce the residual electrolyte on the graphite surface from 3.2wt% to 0.5wt%, and the electrochemical performance after regeneration reaches 98% of that of new graphite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic diagram of the material flow sequence of a waste ternary lithium battery recycling and sorting device provided by an embodiment of the present invention;

[0026] Figure 2 A flowchart of the steps of using a waste ternary lithium battery recycling and sorting device provided in an embodiment of the present invention;

[0027] Figure 3 A flowchart of the operation mode of the crushing module in the method of using a waste ternary lithium battery recycling and sorting device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The technical solutions of the present invention are described below with reference to the accompanying drawings. It is also noted that, to provide a more detailed description, the following embodiments are best and preferred embodiments, and those skilled in the art may employ alternative implementations for certain known technologies. Furthermore, the accompanying drawings are intended only to provide a more detailed description of the embodiments and are not intended to limit the present invention.

[0029] It should be noted that references in the specification to "one embodiment," "an embodiment," "exemplary embodiments," "some embodiments," etc. indicate that the described embodiments may include specific features, structures, or characteristics, but not necessarily every embodiment will include such specific features, structures, or characteristics. Furthermore, when specific features, structures, or characteristics are described in conjunction with an embodiment, it is within the knowledge of persons skilled in the relevant art to implement such features, structures, or characteristics in conjunction with other embodiments (whether or not explicitly described).

[0030] In general, terms can be understood, at least in part, from their use in context. For example, depending at least in part on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending at least in part on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0031] like Figures 1 to 3 As shown, an embodiment of the present invention provides a waste ternary lithium battery recycling and sorting device and a method for using the same, wherein, in a waste ternary lithium battery recycling and sorting device, the crushing module first completes the discharge, disassembly and crushing of the waste ternary lithium battery. After crushing, the black powder and metal particles are separated. The black powder is transported to the roasting module through a sealed screw conveyor, and the metal particles are discharged through the side discharge port. The roasting module is connected to the downstream of the crushing module, and a suspended roasting furnace is used to perform reducing gas suspension roasting on the black powder to decompose the organic matter in the black powder. This connection ensures the efficient roasting of the black powder and the thorough removal of organic matter, laying the foundation for subsequent metal recovery.

[0032] The calcined black powder enters a multi-stage magnetic separation module for further separation. This module includes a superconducting magnetic separator, a hydrocyclone, and a high-gradient magnetic separator, each used to separate magnetic metal oxides, graphite, and other metallic impurities. After wet grinding, the calcined material passes through a superconducting magnetic separator to remove magnetic metal oxides. Non-magnetic materials are further separated by a hydrocyclone. The remaining light-phase graphite finally enters a high-gradient magnetic separator to remove metallic impurities. This connection effectively separates the different components of the black powder, improving the purity of the recovered metals.

[0033] After magnetic separation, the metal oxides and graphite enter the acid leaching and purification module for further metal recovery. The acid leaching and purification module consists of two reaction tanks: one for preferentially leaching lithium and the other for selectively leaching nickel, cobalt, and manganese. This module effectively separates and recovers various metals through precise pH control and the addition of reducing agents. This connection ensures efficient metal recovery and purity control during the acid leaching process.

[0034] After processing in the acid leaching and purification module, the residue (e.g., graphite) is transported to the graphite processing module. This module uses countercurrent water washing tanks, air classifiers, and other equipment to purify and size-classify the sorted graphite. The washed graphite is then dried in a flash dryer to ensure purity and optimal particle size. This connection not only ensures efficient graphite processing and resource recovery, but also lays the foundation for subsequent graphite recombination and utilization.

[0035] The circulation module is connected to the acid leaching and purification module. Through a precipitation device and a solution return line, it enables the recovery of metal solution and the circulation of unsaturated liquid. The liquid after acid leaching and purification passes through the precipitation device to remove insoluble matter. The remaining unsaturated solution is returned to the acid leaching and purification module through the return line for recycling. A conductivity sensor monitors the solution's conductivity in real time, and a proportional-integral valve adjusts the amount of water added to the return flow to ensure the circulation and effective utilization of the acid leaching liquid. This connection not only reduces waste liquid emissions but also improves the economic and environmental performance of the recovery process.

[0036] Through the organic connection and coordinated operation of these modules, the recycling device achieves efficient recycling and resource utilization of spent ternary lithium batteries. Precise parameter adjustment in each module ensures high purity and recovery rate of recovered metals, reducing resource waste and environmental pollution. Furthermore, the recycling of waste liquid and unreacted solution reduces the environmental burden and enhances the sustainability of the entire recycling process. Overall, this modular and systematic design significantly improves the efficiency and economic benefits of recycling spent ternary lithium batteries.

[0037] In one possible embodiment, the crushing module includes a crushing roller, a vibrating screening mechanism, and a sealed screw conveyor. The crushing roller rotates in opposite directions through an interlaced blade structure and a gear set to complete the crushing of the battery. The crushed material is screened by a vibrating screening mechanism, the black powder is transported to the roasting module through a sealed screw conveyor, and the metal particles are discharged through the side discharge port. The inclination angle of the vibrating screening mechanism is adjustable so that the screening effect can be adjusted according to different material characteristics and the separation efficiency of the crushed material can be optimized. This connection enables the crushing, screening, conveying and material diversion processes to be precisely coordinated, thereby improving the efficiency of material sorting.

[0038] The roasting module includes a suspension roasting furnace, a reducing gas injection device, and a temperature control system. The suspension roasting furnace's feed inlet is connected to the outlet of a sealed screw conveyor. The black powder undergoes a reducing gas suspension roasting process in a mixture of nitrogen and hydrogen. The temperature control system regulates the roasting temperature based on the type of binder in the black powder to ensure efficient decomposition of organic matter. The roasted material enters a multi-stage magnetic separation module for separation of magnetic materials, ensuring further purification and effective processing. This connection optimizes gas flow rate and temperature control during the roasting process, ensuring the complete removal of organic matter from the black powder and preparing for subsequent metal recovery.

[0039] The multi-stage magnetic separation module consists of a superconducting magnetic separator, a hydrocyclone, and a high-gradient magnetic separator. The magnetic product from the superconducting magnetic separator is connected to the acid leaching and purification module via an airtight pipeline, with a solenoid valve installed within the pipeline to control the material flow. After the non-magnetic product is separated by the hydrocyclone, the light graphite phase enters the high-gradient magnetic separator for secondary separation via a negative pressure suction system, while the heavy metallic impurities are discharged through a pneumatic gate at the bottom. This connection ensures the separation of magnetic and non-magnetic materials and precise control of material flow, providing suitable raw materials for the subsequent acid leaching and purification process.

[0040] The acid leaching and purification module consists of a two-stage acid leaching tank, a sedimentation tank, and a solution return line. The acidic environment in the first acid leaching tank is monitored by a pH sensor, and the leachate is pumped to the sedimentation tank for processing via a centrifugal pump. The acid leaching residue is dehydrated by a belt filter press and then enters the second acid leaching tank. A reducing agent is added to the second acid leaching tank, with the amount controlled by a metering pump. The leachate is then introduced into a cascade sedimentation device via corrosion-resistant piping. The solution produced after acid leaching enters the graphite processing module through a return line. The graphite is further purified and size-graded through a countercurrent water washing tank and an air classifier. This connection effectively recovers metal ions from the acid leaching solution and provides an excellent foundation for high-purity graphite processing.

[0041] The graphite processing module includes a countercurrent water washing tank, an airflow classifier, and a functionalization treatment device. The countercurrent water washing tank is equipped with an ultrasonic oscillator, which cleans the graphite with circulating water. The filtered graphite is then dried in a flash dryer. The airflow classifier separates the dried graphite into oversize and undersize fractions based on particle size. The oversize fraction enters a rotary carbonization furnace, where it is mixed with asphalt for further processing. The undersize fraction is then pneumatically conveyed and combined with molybdenum disulfide in a high-speed mixer. This precise control of graphite purification and processing ensures improved graphite quality and recovery.

[0042] The circulation module includes a conductivity sensor, a proportional-integral valve, and a central control module. Unsaturated solution is returned through a reflux line to the wet grinding process water supply port of the multi-stage magnetic separation module. The water supply is dynamically adjusted based on feedback from the conductivity sensor. The conductivity sensor monitors the solution's conductivity in real time to ensure solution stability. The proportional-integral valve adjusts the amount of reflux fluid based on the feedback signal, achieving effective solution recycling and reducing chemical waste.

[0043] Through the precise connection and coordinated operation of each module, the entire recycling device achieves efficient recycling and resource utilization of spent ternary lithium batteries. The seamless integration of crushing, roasting, magnetic separation, acid leaching, graphite treatment, and recycling not only improves recovery rates and resource utilization efficiency, but also reduces environmental pollution and energy consumption. By precisely controlling the operating parameters of each link, ensuring the efficiency and sustainability of each step, the device achieves high economic and environmental performance in the recycling of spent ternary lithium batteries.

[0044] Correspondingly, an embodiment of the present invention also provides a method for using a waste ternary lithium battery recycling and sorting device, which is applied to a waste ternary lithium battery recycling and sorting device described in an embodiment of the present invention, and the discharged battery module is first crushed by a crushing roller. After crushing, the material enters the vibrating screening mechanism, and the black powder and metal particles are separated by screening. The vibrating screening mechanism is equipped with dynamically adjustable screen parameters, which can monitor the black powder particle size distribution in real time and adjust the screen parameters according to demand. The black powder is transported to the suspension roasting furnace through a conveying system. The dynamic adjustment of the gas mixing ratio and temperature during the roasting process is based on the detection results of the binder type in the black powder to ensure that the black powder is in a suspended state and optimize the decomposition of organic matter. This process ensures an efficient connection between crushing, screening and transportation, and provides a suitable initial state for subsequent roasting and material processing.

[0045] The calcined material undergoes wet grinding until it reaches the target particle size. It then enters a superconducting magnetic separator for magnetic separation. Based on the material's magnetic characteristics, the superconducting magnetic separator separates magnetic metal oxides and non-magnetic products. The non-magnetic products are then graded by density in a hydrocyclone, and the light phase undergoes secondary separation in a high-gradient magnetic separator to remove any remaining metallic impurities. This multi-stage magnetic separation and classification effectively separates different types of materials, laying the foundation for subsequent acid leaching and purification.

[0046] After the magnetic metal oxides are mixed with the treated non-magnetic product, they enter the acid leaching step. Based on the real-time pH monitoring, the system dynamically adds organic acid and chelating agents to preferentially leach lithium and complex metallic impurities, producing an acid leaching residue. Next, through dynamic control of the reducing agent injection level, the acid leaching residue selectively leaches metals such as nickel, cobalt, and manganese at high temperatures, ultimately yielding graphite. The pH sensor and dynamic control system in this step ensure efficient leaching and selective recovery of metals, optimize the metal ion extraction process, and improve resource recovery.

[0047] The graphite obtained after the secondary acid leaching undergoes multiple stages of countercurrent washing until its conductivity meets the required standard. The washed graphite then enters a drying stage to ensure the removal of moisture. The dried graphite is then graded according to particle size. The graded graphite then undergoes carbonization repair and lubricant compounding to restore its properties. This countercurrent washing and drying process ensures the purity of the graphite, providing high-quality raw material for subsequent use.

[0048] The liquid after the first stage of acid leaching reacts with sodium carbonate to produce lithium carbonate. The remaining unsaturated solution is monitored in real time by a conductivity sensor, and the proportional integral valve is controlled to return it to the wet grinding process, thereby achieving efficient recovery of lithium. The second stage of acid leaching liquid passes through a three-stage pH adjustment device for further metal separation. The specific operation is: Fe or Al is precipitated at pH = 4.3 ± 0.1, Ni or Co is precipitated at pH = 9.0 ± 0.2, and Mn is precipitated at pH = 11.0 ± 0.3, and finally the recovery of the ternary metal is completed. This operation achieves efficient purification of different metals through precise pH control, ensuring the selective recovery of each metal element and maximum utilization of resources.

[0049] Precise connections and operations between modules ensure efficient recycling and resource utilization of spent ternary lithium batteries. Each step has a clear control mechanism, and dynamic adjustment of parameters (such as gas mixing ratio, temperature, pH value, conductivity, etc.) maximizes the efficiency and effectiveness of the recycling process. For example, dynamic screening and roasting temperature control in step 1 ensure the complete decomposition of organic matter; magnetic separation and hydraulic classification in step 2 effectively improve the separation accuracy of metals and non-metallic substances; acid leaching and reducing agent injection in step 3 ensure the selective recovery of metals; graphite washing and drying in step 4 ensure the quality of recovered graphite; and metal recovery in step 5 achieves efficient purification of ternary metals through precise pH adjustment. The seamless integration of the entire system not only improves recycling efficiency, but also reduces energy consumption and environmental impact, maximizing resource utilization in the recycling of spent lithium batteries.

[0050] In one possible embodiment, the crushing rollers in the crushing module employ a staggered blade structure and operate in a counter-rotating manner. This counter-rotating method can effectively increase the degree of material crushing, reduce the time the material remains between the rollers, and improve crushing efficiency. The spacing of the crushing rollers is controlled by a hydraulic adjustment system, with a spacing range of 0.8-1.5mm. This control range ensures that the battery modules can be finely crushed while avoiding material loss caused by excessive crushing. The precise control of the hydraulic system allows the spacing to be flexibly adjusted according to the characteristics of different battery modules, ensuring the best crushing effect each time.

[0051] The vibrating screening mechanism dynamically adjusts the screen's tilt angle during processing. When the black powder layer exceeds 10 cm in thickness, the servo motor drives the screen's tilt angle from an initial 25° to 35°. This dynamic adjustment effectively improves screening efficiency even when black powder accumulates significantly. A larger tilt angle accelerates the separation of black powder from metal particles, improving screening efficiency and reducing the risk of clogging. This intelligent dynamic adjustment not only optimizes screening results but also makes the entire recycling process more flexible to accommodate varying material characteristics.

[0052] A sealed screw conveyor transports crushed materials to the next processing stage. Its screw speed is controlled by a frequency converter within a range of 15-25 rpm. This speed range ensures that the material does not flow too fast or too slow during conveying, thus preventing blockages and maintaining stable conveying quality. To further optimize material conveying, a sealing pressure of 0.05-0.1 MPa is maintained during conveying. Controlling the sealing pressure not only helps prevent material leakage and external contamination but also ensures a highly effective seal throughout the entire system, preventing gas leaks and environmental pollution.

[0053] In one possible embodiment, the suspension roasting furnace sprays a mixture of nitrogen and hydrogen into the furnace through a reducing gas injection device. The device evenly distributes the gas through an annular distributor to ensure that the gas can cover the entire material bed, avoiding differences in roasting effects caused by uneven gas distribution. The mixing ratio of nitrogen and hydrogen is precisely controlled by a mass flow meter to ensure that the gas volume ratio is between 3:1 and 5:1. This ratio is controlled to optimize the reducing atmosphere. The addition of hydrogen can effectively reduce the oxidation state of metal oxides in the battery, providing more favorable conditions for the subsequent sorting process. A reasonable gas volume ratio ensures the smooth progress of the reduction reaction and avoids gas waste.

[0054] The calcination temperature needs to be appropriately set based on the characteristics of the different binder types used in used batteries. For example, if the battery uses PVDF (polyvinylidene fluoride) as a binder, the calcination temperature should be set between 450-500°C; if CMC (carboxymethyl cellulose) is used as a binder, the calcination temperature should be set between 350-400°C. By adjusting the temperature based on the thermal stability and decomposition characteristics of different binders, the calcination process can not only be more efficient but also effectively prevent the side effects of excessively high or low temperatures, such as excessive thermal decomposition of the material or incomplete removal of binder residue.

[0055] The gas flow rate within the furnace is crucial for maintaining the material's suspension. The set airflow velocity needs to be maintained between 0.8 and 1.2 m / s to ensure that the material remains suspended within the furnace, achieving uniform heating and roasting. Too low an airflow velocity can cause material sedimentation, affecting roasting results; while too high an airflow velocity can cause material to be carried out of the furnace, wasting energy and potentially affecting roasting uniformity. By precisely controlling the flow rate, the material is kept in a well-balanced state within the furnace, ensuring the stability and effectiveness of the roasting process.

[0056] In one possible embodiment, during the recycling process, the superconducting magnetic separator dynamically adjusts the magnetic field strength by detecting the content of metal oxides in the waste ternary lithium batteries. The X-ray fluorescence analyzer is responsible for real-time monitoring of the metal oxide content in the battery and transmitting the data to the magnetic separator. Based on the detection results, the superconducting magnetic separator automatically adjusts its magnetic field strength to ensure efficient separation of metal enrichments such as nickel, cobalt, and manganese within the separation field strength range of 1.0-1.5T. Through this precise adjustment, the superconducting magnetic separator can effectively remove metal oxides from waste batteries, improve recovery rates and reduce losses. This dynamic adjustment process ensures the efficient sorting of metal components in different batteries, reduces errors in the magnetic separation process, and improves the adaptability and stability of the system.

[0057] The hydrocyclone is primarily used to process fine-particle materials after sorting. Its feed pressure is controlled by a centrifugal pump between 0.3 and 0.5 MPa. The centrifugal pump provides a stable flow rate and pressure, ensuring that the material is fully dispersed upon entering the hydrocyclone and entering the cyclonic separation stage. Adjusting the feed pressure ensures that the hydrocyclone effectively separates lighter materials, such as graphite and other lighter components, while simultaneously discharging heavy metals through the underflow port. The ratio of the underflow port diameter to the overflow port height is set at 1:2. This design ensures good material distribution within the hydrocyclone and optimizes the separation effect.

[0058] A high-gradient magnetic separator is used to further remove residual metal impurities from the sorted graphite. The magnetic medium fill rate of this separator needs to be controlled between 70-80% to ensure that the magnetic medium can effectively absorb fine metal impurities and separate them from the graphite under the high-gradient magnetic field. Through this step, the metal impurity content in the sorted graphite can be controlled to below the standard of ≤0.3wt%. The high-gradient magnetic separator has a strong magnetic field strength, which can capture trace metal impurities in the graphite, thereby further improving the purity of the recycled battery product.

[0059] The combined use of a superconducting magnetic separator, a hydrocyclone, and a high-gradient magnetic separator enables efficient recycling and sorting of used ternary lithium batteries. First, the superconducting magnetic separator dynamically adjusts the magnetic field strength to precisely separate metal oxides, ensuring efficient separation of nickel, cobalt, and manganese. Second, the hydrocyclone precisely controls the feed pressure, optimizing the separation of light and heavy materials and reducing impurities in the graphite. Finally, the high-gradient magnetic separator further removes metallic impurities from the graphite, ensuring product purity. This synergistic effect significantly improves the recycling efficiency of used batteries, effectively ensuring the purity of the recovered metal and graphite components, reducing environmental pollution, and improving resource utilization.

[0060] In one possible embodiment, during the acid leaching purification process, the pH value of a section of the acid leaching tank has a significant impact on the progress of the reaction. By installing a pH sensor, the pH value of the reaction liquid can be monitored in real time. When the pH value exceeds 3.5, the system automatically activates a metering pump to inject citric acid solution into the acid leaching tank. The addition of citric acid can effectively lower the pH value of the reaction liquid, maintaining it within the ideal range of 2.5-3.0, thereby ensuring sufficient dissolution of metal ions and improving leaching efficiency. This automatic adjustment mechanism can maintain a stable pH value during the reaction, optimize the acid leaching effect, and avoid incomplete metal recovery caused by overly rapid or slow reactions.

[0061] Belt filter presses are primarily used to separate solid material (filter cake) from liquid after acid leaching. During this process, the filter belt's speed must be precisely controlled by a variable-frequency motor, maintaining it within a range of 1-2 m / min. This speed control ensures optimal separation of liquid and solid materials. Slower belt speeds increase filtration time, ensuring adequate dehydration of solids while also preventing excessively fast belt speeds that could lead to high moisture content in the filter cake, potentially impacting subsequent processing. The moisture content of the filter cake after filtration is strictly controlled to ≤15%, providing an excellent foundation for subsequent processing steps and minimizing the adverse effects of moisture.

[0062] The addition of reducing agents is crucial during the secondary acid leaching stage. Using a metering pump, the system accurately adds reducing agents at a rate of 5-8% of the acid leaching residue's mass. The reducing agent promotes the reduction of metal ions, further dissolving them in the liquid phase. Precisely controlling the amount of reducing agent added avoids waste caused by excessive addition while ensuring the full progress of the reaction. Furthermore, the reaction temperature ramp rate is controlled at 5°C / min. This temperature control system ensures a smooth temperature change during the reaction, preventing incomplete chemical reactions or side reactions caused by rapid temperature increases. Precise control of the temperature gradient ensures reaction stability and efficiency.

[0063] Through the synergistic effect of the above steps, the acid leaching purification module can achieve an efficient and precise purification process. First, the linkage control of the pH sensor and the metering pump ensures the stability of the pH value during the reaction process and optimizes the leaching efficiency of the metal. The speed control of the belt filter press enables the filter cake to be effectively dehydrated, reducing the difficulty of subsequent processing. The precise adjustment of the amount of reducing agent added and the temperature control system in the second-stage acid leaching tank not only improves the dissolution rate of the metal, but also ensures the efficient progress of the reaction and avoids waste of resources. Overall, this acid leaching purification process significantly improves the recycling efficiency of waste ternary lithium batteries through intelligent and automated control, ensures the quality of the purified metal, and reduces the risk of environmental pollution.

[0064] In one possible embodiment, during the graphite recovery process, the function of the countercurrent water washing tank is to remove impurities and harmful substances attached to the graphite surface. In order to improve the washing effect, the countercurrent water washing tank is equipped with an ultrasonic oscillator, and its frequency is set to 28kHz±2. The ultrasonic oscillator can promote the full contact between the washing water and the graphite particles through the oscillation of sound waves, thereby more efficiently removing the attachments on the graphite surface. In order to ensure the efficiency of the washing process, the circulating flow rate of the washing water and the graphite feed amount maintain a ratio of 1.5:1, that is, the flow rate of the washing water should be 1.5 times the graphite feed amount. This ratio can ensure the uniform distribution of graphite during the washing process, maximize the utilization efficiency of the washing water, avoid the accumulation and blockage of graphite particles, and ensure the continuity and efficiency of the cleaning process.

[0065] During the graphite processing process, a flash dryer is used to remove moisture from the graphite particles. A PID controller precisely controls the hot air inlet temperature of the dryer, maintaining it within the range of 180-220°C. This temperature range effectively evaporates moisture from the graphite particles while preventing damage from excessive temperatures. The PID controller adjusts the hot air temperature based on real-time feedback data, ensuring a stable and efficient drying process. During the drying process, the moisture content of the outlet material is kept at ≤0.5%. This low moisture content ensures that the dried graphite particles have excellent physical properties and provides an ideal foundation for subsequent carbonization.

[0066] The rotary carbonization furnace is a key piece of equipment in graphite processing, used to further enhance the purity and quality of graphite through high-temperature treatment. The carbonization process consists of three stages: First, the temperature is gradually increased from 600-800°C and maintained for 30 minutes to remove volatile impurities from the graphite; then, the temperature is raised to 1000-1200°C for a two-hour carbonization treatment to further remove residual impurities and improve the structural stability and electrical conductivity of the graphite; finally, the temperature is lowered to 500-600°C for cooling. This process prevents rapid temperature changes from damaging the graphite structure while ensuring the stability of its physical properties.

[0067] In one possible implementation, the core of the circulation module is to monitor the conductivity of the reflux liquid in real time, and continuously detect the conductivity value of the reflux liquid through a conductivity sensor. When the conductivity value exceeds 50μS / cm, it means that the impurity concentration in the reflux liquid is high, which may affect the effect of the subsequent treatment process. At this time, the proportional integral valve will automatically close the reflux channel and start the ion exchange resin purification unit. Through the action of the ion exchange resin, the excess ions in the reflux liquid will be effectively removed, thereby ensuring the stability of the liquid quality in the subsequent process. This linkage control system can respond to changes in liquid quality in real time and automatically adjust the treatment method, avoiding the lag of manual operation and improving the automation and accuracy of the treatment.

[0068] The cascade sedimentation system is used to precipitate and separate harmful substances from wastewater by adjusting the pH value. To precisely control the precipitation effect, the system features a three-stage pH adjustment system, which injects three different solutions via metering pumps: NaOH (sodium hydroxide), NH4HCO3 (ammonia carbonate), and Ca(OH)2 (calcium hydroxide). These solutions are used to adjust the pH to different levels, ensuring optimal precipitation results at each stage. The pH adjustment accuracy is ±0.1 pH, ensuring precise control of the reaction environment, effectively promoting the precipitation and separation of metal ions in the wastewater, and improving recovery efficiency. This precise pH adjustment system effectively avoids over- or under-adjustment, reduces reagent waste, and enhances environmental friendliness.

[0069] In order to ensure the continuous flow of liquid in the system and the liquid balance during the wet grinding process, the reflux rate of the unsaturated solution needs to be linked with the water supply port of the wet grinding process for adjustment. The flow rate of the reflux liquid is monitored by a turbine flowmeter. At the same time, the water supply port of the wet grinding process is equipped with a pressure sensor to monitor the water supply pressure in real time. When the reflux rate of the reflux liquid changes, the pressure sensor will automatically adjust the water supply flow rate so that the water supply pressure remains between 0.2-0.4MPa, ensuring the stability and continuity of the wet grinding process. This linkage adjustment mechanism can respond to changes in process requirements in real time and maintain the stable operation of the entire reflux system, thereby ensuring uniform distribution of liquid and particles during the wet grinding process and reducing possible blockages or liquid flow fluctuations.

[0070] In one possible implementation, the central control module detects the purity of the metal particles after crushing by the crushing module in real time, paying particular attention to the copper / aluminum content. When it is detected that the copper / aluminum content is lower than the preset threshold for three consecutive times, the central control system automatically performs an adjustment operation. Specifically, the system adjusts the spacing between the crushing rollers to optimize the crushing effect, making the particles more uniform and avoiding over-crushing or under-crushing. At the same time, the system will also extend the vibration screening time to ensure that the crushed metal particles can be sorted more effectively and improve the separation accuracy of copper / aluminum particles. The core purpose of this control method is to ensure that the crushed particles meet the requirements of subsequent processes, especially the metal recovery efficiency.

[0071] The function of the roasting module is to remove harmful substances (such as PVDF) from used batteries through high-temperature pyrolysis. The central control module monitors the pyrolysis peak intensity of PVDF in the roasting module in real time. This peak intensity is closely related to the pyrolysis process of PVDF. When the system detects that the PVDF pyrolysis peak intensity is greater than the preset threshold, it indicates that the decomposition of PVDF is not complete and may require more heat for complete decomposition. At this time, the central control module automatically adjusts the temperature of the roasting furnace, increases the temperature of the suspension roasting furnace, and increases the volume ratio of nitrogen to hydrogen to optimize the atmosphere conditions for the roasting reaction and accelerate the pyrolysis process of PVDF. Increasing the ratio of nitrogen to hydrogen helps to improve the reducing atmosphere during the roasting process, promotes the removal of harmful substances, and reduces the generation of residues.

[0072] Through the coordinated control of the crushing module and the roasting module by the central control module, the entire recycling and sorting device can achieve highly automated and precise operation. First, the optimized control of the crushing module can ensure the purity of the metal particles and avoid low metal recovery rates due to insufficient or excessive crushing. Extending the vibration screening time can effectively improve the sorting effect of metal particles and ensure the sorting accuracy in subsequent steps. Secondly, the temperature and atmosphere adjustment of the roasting module can improve the pyrolysis efficiency of PVDF and ensure the complete removal of harmful substances, thereby improving the environmental friendliness and safety of the recycling process. Through real-time monitoring and feedback mechanisms, the central control system can automatically adjust process parameters to maximize recycling efficiency and energy utilization, reduce manual intervention, and ensure the stable operation of the system. This automated control system makes the entire waste ternary lithium battery recycling process more refined, energy-saving and efficient, and has high technical advantages and market competitiveness.

[0073] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0074] In this invention, this modular design improves the efficiency of each module through precise process flow and dynamic parameter adjustment, particularly in the metal and graphite recovery process. Systematic feedback control and real-time monitoring avoid excessive processing or resource waste, and enable real-time adjustment of process parameters at each stage to ensure high purity and recovery rates of the recovered materials. Furthermore, the recovery of wastewater and purification of graphite significantly reduces environmental pollution, contributing to the sustainable utilization of resources.

[0075] The present invention encompasses any alternatives, modifications, equivalents, and solutions that fall within the spirit and scope of the present invention. While specific details are described in detail in the preferred embodiments to provide a thorough understanding of the present invention, those skilled in the art will be able to fully understand the present invention without these details. Furthermore, to avoid unnecessary confusion regarding the essence of the present invention, well-known methods, processes, procedures, components, and circuits have not been described in detail.

[0076] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A waste ternary lithium battery recycling and sorting device, characterized in that: include: Crushing module, used to discharge, disassemble and crush used ternary lithium batteries, and separate black powder and metal particles; The roasting module is connected to the downstream of the crushing module and is used to perform reducing gas suspension roasting on the black powder to decompose organic matter; Multi-stage magnetic separation module, including a superconducting magnetic separator and hydrocyclone connected in series, and a high-gradient magnetic separator, for separating magnetic metal oxides, graphite and metallic impurities; Acid leaching and purification module, including two-stage reaction tanks, used for preferential leaching of lithium and selective leaching of nickel, cobalt and manganese respectively; Graphite processing module, used to purify and grade the sorted graphite; a circulation module, comprising a precipitation device and a solution reflux pipeline connected to the acid leaching purification module, for recovering the metal solution and circulating the unsaturated liquid; The crushing module, roasting module, multi-stage magnetic separation module, acid leaching purification module, graphite processing module and circulation module are connected in the order of material flow, and the output of the previous module is the input of the subsequent module; The crushing module includes symmetrically arranged crushing rollers, a vibrating screening mechanism and a sealed screw conveyor, wherein: The surface of the crushing roller is provided with a staggered blade structure, and the battery is crushed by the reverse rotation of the gear set; The inclination angle of the vibrating screening mechanism is adjustable. The screened black powder is transported to the roasting module through a sealed screw conveyor, and the metal particles are discharged through the side discharge port. The roasting module includes a suspension roasting furnace, a reducing gas injection device and a temperature control system, wherein: The feed port of the suspension roasting furnace is connected to the outlet of the sealed screw conveyor, and a mixed gas of nitrogen and hydrogen is introduced into the furnace, and the gas flow rate is dynamically adjusted by a solenoid valve; The temperature control system regulates the baking temperature according to the type of binder in the black powder; The multi-stage magnetic separation module includes a superconducting magnetic separator, a hydrocyclone and a high gradient magnetic separator, among which: The magnetic product outlet of the superconducting magnetic separator is connected to the acid leaching purification module through an airtight pipeline, and a solenoid valve is provided in the pipeline to control the material flow; After the non-magnetic products are separated by the hydrocyclone, the light phase graphite enters the high gradient magnetic separator for secondary separation through the negative pressure suction system, and the heavy phase metal impurities are discharged through the pneumatic gate at the bottom; The acid leaching and purification module includes a two-stage acid leaching tank, a precipitation tank and a solution reflux pipeline, among which: A pH sensor is installed in the first acid leaching tank. The leachate from the first acid leaching tank is transported to the sedimentation tank via a centrifugal pump. The acid leaching residue is dehydrated by a belt filter press and then enters the second acid leaching tank. The reducing agent is injected into the second-stage acid leaching tank through a metering pump, and the leachate is introduced into the cascade sedimentation device through a corrosion-resistant pipeline. The inner wall of the pipeline is coated with a polytetrafluoroethylene layer; The graphite processing module includes a countercurrent water washing tank, an airflow classifier and a functional treatment device, wherein: The countercurrent water washing tank is equipped with an ultrasonic oscillator, and the washing water is recycled through a multi-layer filter screen, and the purified graphite is processed in a flash dryer; The airflow classifier separates the dry graphite into oversize and undersize according to the particle size. The oversize is mixed with asphalt through a screw feeder and then enters the rotary carbonization furnace. The undersize is compounded with molybdenum disulfide in a high-speed mixer through a pneumatic conveying system. The circulation module includes a conductivity sensor, a proportional-integral valve, and a central control module, including: The unsaturated solution is returned to the water replenishment port of the wet grinding process of the multi-stage magnetic separation module through the reflux pipe. The amount of water replenishment is dynamically adjusted through the proportional integral valve according to the feedback signal of the conductivity sensor.

2. The method for using the waste ternary lithium battery recycling and sorting device according to claim 1, characterized in that: The following steps are involved: Step 1: The discharged battery modules are crushed by a crushing roller. The black powder particle size distribution is monitored in real time by a vibrating screening mechanism, and the screen parameters are dynamically adjusted to separate the black powder and metal particles. The black powder is then transported to a suspension roasting furnace. A reducing gas is introduced, and the gas mixing ratio and roasting temperature are dynamically adjusted based on the detection results of the binder type in the black powder to keep the material in a suspended state and decompose organic matter. Step 2: After calcination, the material is wet-grinded to the target particle size and then enters a superconducting magnetic separator to separate magnetic metal oxides and non-magnetic products based on the magnetic characteristics of the material. The non-magnetic products are graded by density in a hydrocyclone, and the light phase products are passed through a high-gradient magnetic separator for a second time to remove residual metal impurities. Step 3: After the magnetic metal oxide is mixed with the non-magnetic product treated in step 2, an organic acid and a complexing agent are dynamically added based on real-time monitoring by a pH sensor to preferentially leach lithium and complex metal impurities to obtain acid leaching residue, completing the first stage of acid leaching. The acid leaching residue is dynamically controlled by the amount of reducing agent injected under high temperature conditions to selectively leach nickel, cobalt and manganese, ultimately obtaining residual graphite, completing the second stage of acid leaching; Step 4: The graphite obtained in step 3 is subjected to multi-stage countercurrent washing until the conductivity meets the standard and then dried. The dried graphite is classified according to particle size and then carbonized and repaired and lubricant compounded; Step 5: The liquid after the acid leaching is precipitated with sodium carbonate to form lithium carbonate. The remaining unsaturated solution is refluxed to the wet grinding process through a proportional integral valve controlled by a conductivity sensor to complete lithium recovery. The second-stage acid leaching liquid passes through a three-stage pH adjustment device to precipitate Fe or Al at pH = 4.3 ± 0.1, Ni or Co at pH = 9.0 ± 0.2, and Mn at pH = 11.0 ± 0.3, thereby completing the recovery of the ternary metals.

3. The method for using the waste ternary lithium battery recycling and sorting device according to claim 2, characterized in that: The crushing module operates in the following manner: The staggered blade structure of the crushing rollers operates in a counter-rotating manner, and the roller spacing is controlled by a hydraulic adjustment system at 0.8-1.5mm; The inclination angle of the vibrating screening mechanism is dynamically adjusted according to the thickness of the black powder accumulation: when the thickness of the black powder layer is greater than 10cm, the servo motor drives the screen mesh inclination angle to increase from 25° to 35°; The screw speed of the sealed screw conveyor is adjusted to 15-25rpm by the frequency converter, and the sealing pressure is maintained at 0.05-0.1MPa during the conveying process.

4. The method for using the waste ternary lithium battery recycling and sorting device according to claim 3, characterized in that: The roasting module operates in the following manner: The reducing gas injection device of the suspension roaster sprays a mixture of nitrogen and hydrogen through an annular distributor, and the gas volume ratio is controlled by a mass flow meter at 3:1-5:1; Set the calcination temperature according to the binder type: PVDF corresponds to 450-500℃, CMC corresponds to 350-400℃; The gas flow rate in the furnace needs to maintain the material in a suspended state, and the required flow rate is set to 0.8-1.2m / s.

5. The method for using the waste ternary lithium battery recycling and sorting device according to claim 4, characterized in that: The multi-stage magnetic separation module operates in the following manner: The magnetic field strength of the superconducting magnetic separator is dynamically adjusted according to the metal oxide content detected by the X-ray fluorescence analyzer. The separation field strength of nickel, cobalt and manganese enrichment is 1.0-1.5T; The feed pressure of the hydrocyclone is controlled at 0.3-0.5 MPa by a centrifugal pump, and the ratio of the underflow port diameter to the overflow port height is 1:2; The magnetic medium filling rate of the high gradient magnetic separator is 70-80%, and the residual metal impurities in the graphite after separation are ≤0.3wt%.

6. The method for using the waste ternary lithium battery recycling and sorting device according to claim 5, characterized in that: The acid leaching purification module operates in the following manner: The pH sensor of one acid leaching tank is linked to a metering pump, which automatically injects citric acid solution when the pH is greater than 3.5 to maintain the reaction pH value at 2.5-3.0; The filter belt speed of the belt filter press is controlled by a variable frequency motor at 1-2m / min, and the moisture content of the filter cake is ≤15%; The reducing agent of the second-stage acid leaching tank is added by a metering pump at a ratio of 5-8% of the mass of the acid leaching residue, and the reaction temperature gradient heating rate is 5°C / min.

7. The method for using the waste ternary lithium battery recycling and sorting device according to claim 6, characterized in that: The graphite processing module operates in the following manner: The frequency of the ultrasonic oscillator in the countercurrent water washing tank was set to 28kHz±2, and the ratio of the washing water circulation flow rate to the graphite feed rate was 1.5:1; The hot air inlet temperature of the flash dryer is maintained at 180-220°C by a PID controller, and the moisture content of the outlet material is ≤0.5%; The temperature control of the rotary carbonization furnace is divided into three stages: 600-800℃ devolatilization for 30min, 1000-1200℃ carbonization for 2h, and 500-600℃ cooling.

8. The method for using the waste ternary lithium battery recycling and sorting device according to claim 7, characterized in that: The loop module operates in the following manner: The conductivity sensor monitors the conductivity of the reflux liquid in real time. When the value is greater than 50μS / cm, the proportional-integral valve closes the reflux channel and starts ion exchange resin purification. The three-stage pH adjustment of the cascade sedimentation device is respectively carried out by injecting NaOH, NH4HCO3 and Ca(OH)2 solutions through metering pumps, with a control accuracy of ±0.1pH; The remaining unsaturated solution reflux is regulated by a turbine flowmeter in conjunction with the pressure sensor at the water supply port of the wet grinding process, and the water supply pressure is stabilized at 0.2-0.4MPa.

9. The method for using the waste ternary lithium battery recycling and sorting device according to claim 8, characterized in that: The waste ternary lithium battery recycling and sorting device further includes a central control module for controlling the various modules in a coordinated manner. The central control module controls the crushing module and the roasting module in the following manner: The central control module detects the purity of the metal particles crushed by the crushing module in real time. When the copper / aluminum content is less than the set threshold for three consecutive times, the central control system automatically adjusts the spacing between the crushing rollers and extends the vibration screening time. The PVDF pyrolysis peak intensity of the roasting module is detected. When the PVDF pyrolysis peak intensity is detected to be greater than the preset threshold, the central control system increases the temperature of the suspension roasting furnace and increases the volume ratio of nitrogen to hydrogen.

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