High-purity rare earth metal recovery method and system of waste rare earth permanent magnet material

Abstract

The invention discloses a high-purity rare earth metal recovery method and system of a waste rare earth permanent magnet material, and relates to the technical field of rare earth metal recovery. The method comprises the following steps: carrying out acid leaching treatment on material particles; continuously monitoring the acid leaching solution by using a pH meter to obtain a pH monitoring value sequence; carrying out fluctuation trend analysis on the pH monitoring value sequence, and when an analysis result meets a preset requirement, carrying out centrifugal separation on the acid leaching solution to obtain a solution to be extracted; adding the solution to be extracted into the extraction box body for rotary extraction; carrying out dynamic periodic detection on the extraction process until a preset extraction stopping condition is met to obtain an extraction solution, carrying out precipitation crystallization on the extraction solution, and cleaning and drying the precipitate to obtain the high-purity rare earth metal salt; and carrying out reduction smelting on the high-purity rare earth metal salt to obtain the high-purity rare earth metal. The technical problem that in the prior art, the recycling efficiency of waste rare earth permanent magnet materials is low is solved, and the technical effect of improving the recycling efficiency of rare earth metal is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of rare earth metal recovery, and in particular to a method and system for recovering high-purity rare earth metals from waste rare earth permanent magnet materials. Background Art

[0002] As an important high-performance material, rare earth permanent magnet materials are widely used in new energy, electronics, aerospace and other fields. However, in the process of their production, processing and product replacement, a large amount of waste rare earth permanent magnet materials are inevitably generated. These waste materials contain rich rare earth resources. If they are not recycled and utilized reasonably and effectively, it will not only cause a waste of rare earth resources, but also cause potential harm to the environment. Most of the existing methods for recycling waste rare earth permanent magnet materials have problems such as low recycling efficiency, complicated processing process and high cost. Therefore, how to efficiently recycle rare earth metals in waste rare earth permanent magnet materials has become a technical problem that needs to be solved urgently in the current rare earth recycling field. Summary of the Invention

[0003] The present application provides a method and system for recovering high-purity rare earth metals from waste rare earth permanent magnet materials, which solves the technical problem of low recovery efficiency of waste rare earth permanent magnet materials in the prior art.

[0004] In a first aspect of the present application, a method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials is provided, the method comprising: Waste rare earth permanent magnet materials are mechanically crushed into material particles, and the material particles are acid-leached using a preset chemical solvent according to a preset leaching parameter group; during the acid leaching process, the acid leaching solution is continuously monitored using a pH meter to obtain a pH monitoring value sequence; a fluctuation trend analysis is performed on the pH monitoring value sequence, and when the analysis result meets the preset requirements, the acid leaching solution is centrifuged to obtain a solution to be extracted; the solution to be extracted is added to an extraction box through a waste material adding component, and an extractant is added to the extraction box through an extractant high-pressure spraying component provided on the extraction box, and the extraction box is driven by a motor to rotate and extract at a first rotation speed; the extraction process is dynamically and periodically detected until a preset extraction stop condition is met to obtain an extraction solution, the extraction solution is precipitated and crystallized, and the precipitate is cleaned and dried to obtain a high-purity rare earth metal salt; the high-purity rare earth metal salt is reduced and smelted to obtain high-purity rare earth metal.

[0005] A second aspect of the present application provides a high-purity rare earth metal recovery system for waste rare earth permanent magnet materials, the system comprising: a processing module for mechanically crushing waste rare earth permanent magnet materials into material particles, and performing acid leaching treatment on the material particles using a preset chemical solvent according to a preset leaching parameter set; a monitoring module for continuously monitoring the acid leaching solution using a pH meter during the acid leaching process to obtain a pH monitoring value sequence; an analysis module for performing fluctuation trend analysis on the pH monitoring value sequence, and when the analysis result meets preset requirements, centrifuging the acid leaching solution to obtain a solution to be extracted; an extraction module for adding the solution to be extracted into an extraction box via a waste material adding component, adding an extractant into the extraction box via an extractant high-pressure spraying component provided on the extraction box, and rotating the extraction box at a first rotation speed via a motor-driven first rotating component for extraction; a detection module for dynamically and periodically detecting the extraction process until a preset extraction stop condition is met, obtaining an extraction solution, precipitating and crystallizing the extraction solution, and washing and drying the precipitate to obtain a high-purity rare earth metal salt; and a smelting module for reducing and smelting the high-purity rare earth metal salt to obtain high-purity rare earth metal.

[0006] One or more technical solutions provided in this application have at least the following technical effects or advantages: First, waste rare earth permanent magnet materials are mechanically crushed into material particles. The particles are then acid-leached using a preset chemical solvent according to a preset set of leaching parameters. During the acid leaching process, the acid leaching solution is continuously monitored using a pH meter to obtain a sequence of pH values. Next, the pH value sequence is analyzed for fluctuation trends. When the analysis results meet preset requirements, the acid leaching solution is centrifuged to obtain a solution to be extracted. The solution to be extracted is then added to an extraction chamber via a waste material addition assembly. Extractant is then added to the chamber via a high-pressure extractant spray assembly mounted on the chamber. A motor-driven first rotating assembly rotates the chamber at a first rotational speed for extraction. The extraction process is dynamically and periodically monitored until a preset extraction stop condition is met. An extraction solution is obtained, which is then precipitated and crystallized, and the precipitate is washed and dried to obtain a high-purity rare earth metal salt. Finally, the high-purity rare earth metal salt is subjected to reduction smelting to obtain high-purity rare earth metals. This method solves the technical problem of low recovery efficiency of waste rare earth permanent magnet materials in the prior art, achieving the technical effect of improving rare earth metal recovery efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] 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.

[0008] Figure 1 A schematic flow chart of a method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials provided in an embodiment of the present application; Figure 2 Schematic diagram of the structure of a high-purity rare earth metal recovery system for waste rare earth permanent magnet materials provided in an embodiment of the present application.

[0009] Description of the accompanying drawings: processing module 11, monitoring module 12, analysis module 13, extraction module 14, detection module 15, smelting module 16. DETAILED DESCRIPTION

[0010] The present application solves the technical problem of low recycling efficiency of waste rare earth permanent magnet materials in the prior art by providing a high-purity rare earth metal recovery method and system for waste rare earth permanent magnet materials.

[0011] The following will be combined with the accompanying drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only some of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0012] It should be noted that the terms "including" and "having" are intended to cover non-exclusive inclusions. For example, a process, method, system, product or server that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or modules that are not clearly listed or are inherent to these processes, methods, products or devices.

[0013] Example 1, as Figure 1 As shown, the present application provides a method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials, wherein the method comprises: Waste rare earth permanent magnet materials are mechanically crushed into material particles, and the material particles are acid-leached using a preset chemical solvent according to a preset leaching parameter group.

[0014] In an embodiment of the present application, waste rare earth permanent magnet materials are crushed into fine particles by mechanical crushing equipment to increase the specific surface area of ​​the material, thereby improving the efficiency of subsequent leaching treatment; the crushed material particles are sent to a reactor and acid-leached using a preset chemical solvent (such as sulfuric acid, hydrochloric acid and other acidic solvents); during the acid leaching process, the chemical solvent is added according to a preset parameter group (acid concentration, liquid-solid ratio, reaction temperature, reaction time, stirring speed), stirring is started, and heating is carried out to the target temperature.

[0015] During the acid leaching process, the acid leaching solution is continuously monitored using a pH meter to obtain a pH monitoring value sequence.

[0016] During the acid leaching process, the pH meter probe is immersed in the solution of the acid leaching reactor and continuous monitoring is performed according to a preset monitoring frequency (such as recording data once every 30 seconds) to generate a pH monitoring value sequence.

[0017] The pH monitoring value sequence is subjected to a fluctuation trend analysis, and when the analysis result meets a preset requirement, the acid leaching solution is centrifuged to obtain a solution to be extracted.

[0018] Furthermore, the preset requirement is that the fluctuation variance of the pH monitoring value is less than or equal to the preset fluctuation variance.

[0019] In the present embodiment, a fluctuation trend analysis is performed on the sequence of pH monitoring values, i.e., the fluctuation variance of the pH monitoring values ​​is calculated to assess changes in the solution's pH. When the pH fluctuation variance is less than or equal to a preset fluctuation variance threshold, the acid leaching reaction has reached the desired stable state and is complete. At this point, the acid leaching solution is centrifuged to remove solid impurities and obtain a solution to be extracted. The solution to be extracted contains rare earth metal ions dissolved during the acid leaching process, and solid impurities have been removed after centrifugation.

[0020] The solution to be extracted is added into the extraction box through the waste adding component, the extractant is added into the extraction box through the extractant high-pressure spraying component arranged on the extraction box, and the first rotating component is driven by the motor to drive the extraction box to rotate at a first rotation speed for extraction.

[0021] The waste material addition assembly introduces the solution to be extracted into the extraction chamber. Next, a high-pressure extraction agent spray assembly, mounted on the extraction chamber, introduces a predetermined extractant into the chamber via a high-pressure spray method. For example, the extractant, pressurized by a high-pressure plunger pump, is sprayed tangentially along the inner wall of the extraction chamber through an annular nozzle array, forming a spiral liquid film coating. The extractant chemically reacts with the rare earth metal ions in the solution to be extracted, extracting the rare earth metals from the solution and forming an easily separable extraction solution.

[0022] The first component is driven by a motor to rotate the extraction box around the horizontal axis at a preset first rotation speed. During the rotation, the solution and the extractant are continuously mixed and contacted, thereby enhancing the efficiency of the dissolution and extraction reactions.

[0023] The extraction process is dynamically and periodically detected until the preset extraction stop condition is met to obtain an extraction solution, which is then precipitated and crystallized, and the precipitate is washed and dried to obtain a high-purity rare earth metal salt.

[0024] While the extraction reaction proceeds within the extraction chamber, dynamic periodic monitoring of the extraction process is performed to ensure that the extractant is fully reacting with the rare earth metal ions in the solution to be extracted. Specifically, within a preset monitoring period, the solute concentration and extractant activity in the solution are sampled and analyzed, generating a concentration change data series and an activity coefficient series. By analyzing the trends of these series, it is determined whether the extraction reaction is stabilizing and, furthermore, whether the preset extraction stop conditions have been met, such as when the solute concentration falls below a set concentration threshold or when the extractant activity has stabilized.

[0025] Once the test results indicate that the extraction process has met the stopping conditions, the extraction operation is immediately terminated and the extraction solution obtained after the reaction is collected. The extraction solution is enriched with the target rare earth metal ions and then subjected to precipitation and crystallization. During the precipitation and crystallization stage, the rare earth metal ions are precipitated from the solution in the form of high-purity salts by adjusting the pH value, adding precipitants, or controlling the temperature. The obtained precipitate is filtered, washed in sequence to remove residual impurities, and then subjected to low-temperature drying to finally obtain a high-purity rare earth metal salt with high purity and low impurity content.

[0026] Furthermore, the extraction process is dynamically and periodically detected until a preset extraction stop condition is met to obtain an extraction solution, including: The extractant activity test and the solute concentration test are performed according to the first sampling test cycle to obtain an extractant activity coefficient sequence and a solute concentration test result sequence; the extractant activity coefficient sequence and the solute concentration test result sequence are analyzed respectively, and whether the extractant needs to be replenished is determined based on the analysis results, and the first sampling test cycle is dynamically adjusted to obtain an extractant activity sampling test cycle and a solute concentration sampling test cycle; the extraction process is dynamically and periodically tested based on the extractant activity sampling test cycle and the solute concentration sampling test cycle until a preset extraction stop condition is met to obtain the extraction solution.

[0027] Furthermore, the preset extraction stop condition is that the solute concentration is lower than a preset solute concentration threshold.

[0028] During the extraction process, the system regularly monitors the reaction system within the extraction chamber according to a pre-set first sampling and detection cycle. The system collects and analyzes extractant activity and solute concentration data, generating a sequence of extractant activity coefficients and a sequence of solute concentration test results. The extractant activity coefficient reflects the residual reactivity of the extractant during the reaction, while the solute concentration is used to assess the degree of extraction of the metal ions being extracted. By analyzing the changing trends of the extractant activity coefficient sequence and the solute concentration test result sequence, the system determines whether the current extraction reaction is at risk of extractant depletion or a decrease in reaction efficiency, and accordingly determines whether the extraction chamber needs to be replenished to maintain reaction efficiency. Based on the analysis results, the system dynamically adjusts the pre-set first sampling and detection cycle to generate new extractant activity and solute concentration sampling and detection cycles, respectively, ensuring that the detection frequency adapts to changes in the reaction state. When the reaction fluctuates significantly, the sampling cycle is automatically shortened to improve response speed; when the reaction stabilizes, the cycle is extended to reduce resource consumption.

[0029] Based on the extractant activity sampling detection cycle and the solute concentration sampling detection cycle, the subsequent extraction process is dynamically and periodically detected, and data is continuously collected and the judgment is updated until the preset extraction stop condition is met (such as the solute concentration drops below the preset solute concentration threshold). At this time, the extraction process is terminated and the final extraction solution is output.

[0030] Furthermore, respectively analyzing the extractant activity coefficient sequence and the solute concentration detection result sequence, determining whether to supplement the extractant according to the analysis results, and dynamically adjusting the first sampling detection period to obtain the extractant activity sampling detection period and the solute concentration sampling detection period, including: Determine whether there is data less than or equal to a preset extractant activity coefficient threshold and a preset solute concentration threshold in the extractant activity coefficient sequence and the solute concentration detection result sequence. If so, obtain a first extractant addition instruction and a first period dynamic adjustment instruction; based on the first extractant addition instruction, call the extractant high-pressure spraying component to add extractant to the extraction box; based on the first period dynamic adjustment instruction, reduce the first sampling detection period by half to obtain an extractant activity sampling detection period and a solute concentration sampling detection period.

[0031] After acquiring a sequence of extractant activity coefficients and solute concentration test results, the system analyzes both sequences in real time to determine if the extraction process is experiencing signs of declining efficiency. Specifically, the system determines whether any data in the sequences contains values ​​less than or equal to a preset extractant activity coefficient threshold or a preset solute concentration threshold. If either condition is met, it indicates a significant decrease in extractant activity or substantial extraction of the target solute. At this point, the extraction process is nearing completion or requires enhanced reaction conditions to maintain efficiency.

[0032] Once the above conditions are met, the system automatically generates the first extractant addition instruction and the first cycle dynamic adjustment instruction. Based on the first extractant addition instruction, the system controls the extractant high-pressure spray assembly to add a certain amount of extractant to the extraction chamber to restore the active environment required for the reaction. At the same time, based on the first cycle dynamic adjustment instruction, the original first sampling detection cycle is reduced to half of the original cycle, thereby increasing the frequency of subsequent detection and enhancing the system's responsiveness to changes in reaction status. Ultimately, the updated detection cycles are set as the new extractant activity sampling detection cycle and solute concentration sampling detection cycle, respectively, providing a foundation for subsequent dynamic detection and process control, ensuring that the entire extraction process continues to operate under efficient and stable conditions.

[0033] Furthermore, when there is no data less than or equal to the preset extractant activity coefficient threshold and the preset solute concentration threshold in the extractant activity coefficient sequence and the solute concentration detection result sequence, a single-point gradient analysis is performed on the extractant activity coefficient sequence and the solute concentration detection result sequence to obtain an extractant activity coefficient gradient decline sequence and a solute concentration gradient decline sequence; an extractant activity coefficient trend analysis is performed based on the extractant activity coefficient gradient decline sequence to obtain an extractant activity coefficient trend factor, and the first sampling detection period is adjusted according to the extractant activity coefficient trend factor to obtain an extractant activity sampling detection period; a solute concentration trend analysis is performed based on the solute concentration gradient decline sequence to obtain a solute concentration trend factor, and the first sampling detection period is adjusted according to the solute concentration trend factor to obtain a solute concentration sampling detection period.

[0034] When analyzing the extractant activity coefficient sequence and the solute concentration test result sequence, if no data in the test sequence is less than or equal to the preset extractant activity coefficient threshold and the preset solute concentration threshold, it indicates that the current extraction process is still in the stable reaction stage and has not yet triggered a significant abnormality or extraction termination condition. At this time, the system will perform a single-point gradient analysis operation on the extractant activity coefficient sequence and the solute concentration test result sequence, respectively. This operation calculates the change amplitude of adjacent test points in the sequence, obtains a gradient sequence reflecting the change rate, and forms a gradient-decreasing sequence of the extractant activity coefficient and the solute concentration, respectively.

[0035] Calculate the gradient of the extractant activity coefficient: ,in, is the activity coefficient of the extractant at time t, is the activity coefficient of the extractant at time t+1, is the time interval.

[0036] Calculate the solute concentration gradient: ,in, is the solute concentration at time t, is the solute concentration at time t+1, is the time interval.

[0037] If the gradient is positive, it means the variable is increasing (for example, the solute concentration is increasing or the extractant activity is increasing); if the gradient is negative, it means the variable is decreasing (for example, the solute concentration is decreasing or the extractant activity is decreasing).

[0038] Based on the gradient-decreasing sequence of the extractant activity coefficient, trend analysis is performed to extract representative features of the changing trend. By statistically analyzing the central trend gradient and the amplitude of the change, an extractant activity coefficient trend factor is generated, which is used to quantify the rate of decline and degree of fluctuation in the extractant activity during the reaction. Based on the extractant activity coefficient trend factor, the first sampling and detection period is dynamically adjusted to obtain an optimized extractant activity sampling and detection period, thereby more accurately matching the actual detection frequency requirements of the reaction process. Similarly, based on the solute concentration gradient-decreasing sequence, the system performs concentration trend analysis to obtain a solute concentration trend factor, which reflects the decreasing concentration trend of the target rare earth metal in the current solution. Based on the solute concentration trend factor, the first sampling and detection period is dynamically adjusted to obtain an optimized extractant activity sampling and detection period.

[0039] Furthermore, the extractant activity coefficient trend analysis is performed based on the extractant activity coefficient gradient descent sequence to obtain the extractant activity coefficient trend factor, including: A central gradient is selected from a gradient descent sequence of an extractant activity coefficient, wherein the central gradient is the mode of the extractant activity coefficient gradients in the gradient descent sequence of the extractant activity coefficient; a trend center neighborhood is constructed with the central gradient as the trend center according to a preset trend radius; a trend center neighborhood density of the trend center neighborhood is calculated; edge diffusion is performed on the trend center neighborhood according to a preset diffusion bandwidth, and diffusion stop identification is performed in combination with the trend center neighborhood density to determine a target trend center neighborhood; and a mean of the target trend center neighborhood is calculated to obtain the extractant activity coefficient trend factor.

[0040] Preferably, a central gradient is selected from the gradient descent sequence of the extractant activity coefficient, that is, the mode of the extractant activity coefficient gradient in the gradient descent sequence of the extractant activity coefficient is selected; the central gradient is used as the trend center, and a trend center neighborhood is constructed in combination with a preset trend radius, that is, a set of intervals formed by expanding up and down in the numerical dimension with the central gradient as the core, which is used to capture gradient change points close to the dominant trend. The number of gradient points contained in the trend center neighborhood is calculated, and the density of the trend center neighborhood is obtained based on this to reflect the significance of the trend pattern. According to the preset diffusion bandwidth, the trend center neighborhood is subjected to edge diffusion processing, that is, the neighborhood range is gradually expanded and the density of the diffusion area is recalculated. After each step of diffusion, the difference between the density of the diffusion trend center neighborhood and the density of the original trend center neighborhood is compared to determine whether the preset diffusion stop condition is met: when the density after diffusion is not lower than the original density, and the density difference is less than or equal to the set threshold, it is considered that the current diffusion range has stabilized, the diffusion is stopped, and it is used as the target trend center neighborhood. Finally, the mean of all gradient values ​​in the neighborhood of the target trend center is calculated and used as the trend factor of the current extractant activity change, which comprehensively reflects the speed and direction of the current extractant activity decline.

[0041] Furthermore, edge diffusion is performed on the trend center neighborhood according to a preset diffusion bandwidth, and diffusion stop identification is performed in combination with the density of the trend center neighborhood to determine the target trend center neighborhood, including: The trend center neighborhood is edge diffused according to a preset diffusion bandwidth to obtain a diffusion trend center neighborhood; when the diffusion trend center neighborhood density of the diffusion trend center neighborhood is greater than or equal to the trend center neighborhood density, and the difference between the diffusion trend center neighborhood density and the trend center neighborhood density is less than or equal to the preset difference, the diffusion is stopped and the diffusion trend center neighborhood is used as the target trend center neighborhood; when the diffusion trend center neighborhood density of the diffusion trend center neighborhood is less than the trend center neighborhood density, the trend center neighborhood is used as the target trend center neighborhood.

[0042] Preferably, the trend center neighborhood is numerically expanded according to a preset diffusion bandwidth, i.e., a diffusion step interval is added to the upper and lower boundaries of the central gradient neighborhood, forming a diffusion trend center neighborhood containing more gradient points. The density within the diffusion trend center neighborhood is calculated, i.e., the number or proportion of gradient data points contained in the neighborhood is counted to obtain the diffusion trend center neighborhood density. The diffusion trend center neighborhood density is then compared with the original trend center neighborhood density to determine: if the diffusion trend center neighborhood density is greater than or equal to the original trend center neighborhood density, and the density difference between the two does not exceed a preset tolerance threshold (i.e., the difference is less than or equal to the preset difference), it is considered that the diffusion has not introduced noise interference and the trend boundary has stabilized. The diffusion operation is terminated, and the current diffusion trend center neighborhood is identified as the target trend center neighborhood. Conversely, if the diffusion trend center neighborhood density is less than the original trend center neighborhood density, it indicates that data points outside the trend boundary are not helpful for trend identification or even interfere with trend identification. The system terminates the diffusion and retains the original trend center neighborhood as the final target trend center neighborhood.

[0043] Furthermore, calculating the mean of the neighborhood of the target trend center to obtain the extractant activity coefficient trend factor also includes: It is determined whether the extraction agent activity coefficient trend factor meets a preset tolerance threshold. If not, extraction abnormality warning information is obtained; and an early warning is issued for the extraction process according to the extraction abnormality warning information.

[0044] After determining the target trend center neighborhood, all gradient values ​​within that neighborhood are statistically calculated to obtain their mean. This is used as a quantitative indicator of the overall trend in extractant activity during the current period, recorded as the extractant activity coefficient trend factor. This trend factor accurately reflects the rate of decline or stability of extractant activity over time and is used to determine whether there are potential anomalies in the extraction process or whether strategy adjustments are needed.

[0045] After the calculation is complete, the system compares the trend factor with a preset tolerance threshold to determine whether the current activity change is within the normal range. If the trend factor does not meet the set tolerance threshold conditions (such as a rapid decline or excessive fluctuation), it indicates that the effective activity of the extractant is abnormally declining, which may lead to a significant decrease in subsequent extraction efficiency or a misjudgment of the extraction endpoint. The system will immediately generate a corresponding extraction abnormality warning message. Based on this extraction abnormality warning message, the system prompts the operator to intervene through the human-machine interface or automatically links the control module to initiate emergency adjustment procedures, such as replenishing the extractant in advance, adjusting the rotation speed, and enhancing mixing, to ensure the continuous and stable operation of the extraction process.

[0046] The high-purity rare earth metal salt is subjected to reduction smelting to obtain high-purity rare earth metal.

[0047] After obtaining high-purity rare earth metal salts, reduction smelting is carried out to extract high-purity rare earth metals from the metal salts.

[0048] Illustratively, the obtained high-purity rare earth metal salt (such as rare earth chloride, nitrate, etc.) is mixed with a reducing agent (such as hydrogen, carbon or a metal reducing agent, etc.); based on the chemical properties of the selected rare earth metal, an appropriate reducing agent is selected to react with the metal salt, usually at a high temperature; through the reduction reaction, the rare earth metal ions in the metal salt are reduced to the corresponding rare earth metal, and precipitated to form solid metal.

[0049] In summary, the embodiments of the present application have at least the following technical effects: First, waste rare earth permanent magnet materials are mechanically crushed into material particles. The particles are then acid-leached using a preset chemical solvent according to a preset set of leaching parameters. During the acid leaching process, the acid leaching solution is continuously monitored using a pH meter to obtain a sequence of pH values. Next, the pH value sequence is analyzed for fluctuation trends. When the analysis results meet preset requirements, the acid leaching solution is centrifuged to obtain a solution to be extracted. The solution to be extracted is then added to an extraction chamber via a waste material addition assembly. Extractant is then added to the chamber via a high-pressure extractant spray assembly mounted on the chamber. A motor-driven first rotating assembly rotates the chamber at a first rotational speed for extraction. The extraction process is dynamically and periodically monitored until a preset extraction stop condition is met. An extraction solution is obtained, which is then precipitated and crystallized, and the precipitate is washed and dried to obtain a high-purity rare earth metal salt. Finally, the high-purity rare earth metal salt is subjected to reduction smelting to obtain high-purity rare earth metals. This method solves the technical problem of low recovery efficiency of waste rare earth permanent magnet materials in the prior art, achieving the technical effect of improving rare earth metal recovery efficiency.

[0050] Example 2, based on the same inventive concept as the method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials in the previous embodiment, Figure 2 As shown, the present application provides a high-purity rare earth metal recovery system for waste rare earth permanent magnet materials, wherein the system includes: The processing module 11 is configured to mechanically crush waste rare earth permanent magnet materials into material particles and acid-leach the material particles using a preset chemical solvent according to a preset leaching parameter set. The monitoring module 12 is configured to continuously monitor the acid leaching solution using a pH meter during the acid leaching process to obtain a pH monitoring value sequence. The analysis module 13 is configured to perform fluctuation trend analysis on the pH monitoring value sequence and, when the analysis result meets preset requirements, centrifuge the acid leaching solution to obtain a solution to be extracted. The extraction module 14 is configured to add the solution to be extracted into an extraction box via a waste material adding component, add an extractant into the extraction box via an extractant high-pressure spraying component provided on the extraction box, and rotate the extraction box at a first rotation speed via a motor-driven first rotating component to perform extraction. The detection module 15 is configured to dynamically and periodically detect the extraction process until a preset extraction stop condition is met, thereby obtaining an extraction solution, precipitating and crystallizing the extraction solution, and washing and drying the precipitate to obtain a high-purity rare earth metal salt. The smelting module 16 is configured to reduce and smelt the high-purity rare earth metal salt to obtain high-purity rare earth metal.

[0051] Furthermore, the detection module 15 is configured to perform the following method: The extractant activity test and the solute concentration test are performed according to the first sampling test cycle to obtain an extractant activity coefficient sequence and a solute concentration test result sequence; the extractant activity coefficient sequence and the solute concentration test result sequence are analyzed respectively, and whether the extractant needs to be replenished is determined based on the analysis results, and the first sampling test cycle is dynamically adjusted to obtain an extractant activity sampling test cycle and a solute concentration sampling test cycle; the extraction process is dynamically and periodically tested based on the extractant activity sampling test cycle and the solute concentration sampling test cycle until a preset extraction stop condition is met to obtain the extraction solution.

[0052] Furthermore, the detection module 15 is configured to perform the following method: The preset extraction stop condition is that the solute concentration is lower than a preset solute concentration threshold.

[0053] Furthermore, the detection module 15 is configured to perform the following method: Determine whether there is data less than or equal to a preset extractant activity coefficient threshold and a preset solute concentration threshold in the extractant activity coefficient sequence and the solute concentration detection result sequence. If so, obtain a first extractant addition instruction and a first period dynamic adjustment instruction; based on the first extractant addition instruction, call the extractant high-pressure spraying component to add extractant to the extraction box; based on the first period dynamic adjustment instruction, reduce the first sampling detection period by half to obtain an extractant activity sampling detection period and a solute concentration sampling detection period.

[0054] Furthermore, the detection module 15 is configured to perform the following method: When there is no data less than or equal to the preset extractant activity coefficient threshold and the preset solute concentration threshold in the extractant activity coefficient sequence and the solute concentration detection result sequence, the extractant activity coefficient sequence and the solute concentration detection result sequence are traversed to perform single-point gradient analysis to obtain an extractant activity coefficient gradient decline sequence and a solute concentration gradient decline sequence; based on the extractant activity coefficient gradient decline sequence, an extractant activity coefficient trend analysis is performed to obtain an extractant activity coefficient trend factor, and the first sampling detection period is adjusted according to the extractant activity coefficient trend factor to obtain an extractant activity sampling detection period; based on the solute concentration gradient decline sequence, a solute concentration trend analysis is performed to obtain a solute concentration trend factor, and the first sampling detection period is adjusted according to the solute concentration trend factor to obtain a solute concentration sampling detection period.

[0055] Furthermore, the detection module 15 is configured to perform the following method: A central gradient is selected from a gradient descent sequence of an extractant activity coefficient, wherein the central gradient is the mode of the extractant activity coefficient gradients in the gradient descent sequence of the extractant activity coefficient; a trend center neighborhood is constructed with the central gradient as the trend center according to a preset trend radius; a trend center neighborhood density of the trend center neighborhood is calculated; edge diffusion is performed on the trend center neighborhood according to a preset diffusion bandwidth, and diffusion stop identification is performed in combination with the trend center neighborhood density to determine a target trend center neighborhood; and a mean of the target trend center neighborhood is calculated to obtain the extractant activity coefficient trend factor.

[0056] Furthermore, the detection module 15 is configured to perform the following method: The trend center neighborhood is edge diffused according to a preset diffusion bandwidth to obtain a diffusion trend center neighborhood; when the diffusion trend center neighborhood density of the diffusion trend center neighborhood is greater than or equal to the trend center neighborhood density, and the difference between the diffusion trend center neighborhood density and the trend center neighborhood density is less than or equal to the preset difference, the diffusion is stopped and the diffusion trend center neighborhood is used as the target trend center neighborhood; when the diffusion trend center neighborhood density of the diffusion trend center neighborhood is less than the trend center neighborhood density, the trend center neighborhood is used as the target trend center neighborhood.

[0057] Furthermore, the detection module 15 is configured to perform the following method: It is determined whether the extraction agent activity coefficient trend factor meets a preset tolerance threshold. If not, extraction abnormality warning information is obtained; and an early warning is issued for the extraction process according to the extraction abnormality warning information.

[0058] Furthermore, the analysis module 13 is used to perform the following method: The preset requirement is that the fluctuation variance of the pH monitoring value is less than or equal to the preset fluctuation variance.

[0059] It should be noted that the order in which the embodiments of the present application are presented is for illustrative purposes only and does not necessarily represent the superiority or inferiority of the embodiments. Furthermore, the foregoing descriptions of specific embodiments of this specification are provided. The processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0060] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

[0061] This specification and drawings are merely illustrative of the present application and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of this application. Obviously, those skilled in the art may make various modifications and variations to this application without departing from the scope of this application. Thus, this application is intended to include such modifications and variations as fall within the scope of this application and its equivalents.

Claims

1. A method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials, characterized in that: The method comprises: The waste rare earth permanent magnet material is mechanically crushed into material particles, and the material particles are acid-leached using a preset chemical solvent according to a preset leaching parameter group; During the acid leaching process, the acid leaching solution is continuously monitored using a pH meter to obtain a pH monitoring value sequence; Performing a fluctuation trend analysis on the pH monitoring value sequence, and when the analysis result meets the preset requirements, centrifuging the acid leaching solution to obtain a solution to be extracted; The solution to be extracted is added into the extraction box through the waste adding assembly, the extractant is added into the extraction box through the extractant high-pressure spraying assembly provided on the extraction box, and the first rotating assembly is driven by a motor to rotate the extraction box at a first rotation speed for extraction; The extraction process is dynamically and periodically detected until a preset extraction stop condition is met to obtain an extraction solution, the extraction solution is precipitated and crystallized, and the precipitate is washed and dried to obtain a high-purity rare earth metal salt; The high-purity rare earth metal salt is subjected to reduction smelting to obtain high-purity rare earth metal.

2. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 1, wherein: The extraction process is dynamically and periodically detected until the preset extraction stop condition is met to obtain the extraction solution, including: Performing an extractant activity test and a solute concentration test according to a first sampling test cycle to obtain an extractant activity coefficient sequence and a solute concentration test result sequence; Analyzing the extractant activity coefficient sequence and the solute concentration test result sequence respectively, determining whether to supplement the extractant according to the analysis results, and dynamically adjusting the first sampling and detection period to obtain the extractant activity sampling and detection period and the solute concentration sampling and detection period; The extraction process is dynamically and periodically detected based on the extractant activity sampling detection period and the solute concentration sampling detection period until a preset extraction stop condition is met to obtain the extraction solution.

3. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 2, wherein: The preset extraction stop condition is that the solute concentration is lower than a preset solute concentration threshold.

4. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 2, wherein: Analyzing the extractant activity coefficient sequence and the solute concentration detection result sequence respectively, determining whether to supplement the extractant according to the analysis results, and dynamically adjusting the first sampling detection period to obtain the extractant activity sampling detection period and the solute concentration sampling detection period, including: Determine whether there is data less than or equal to a preset extractant activity coefficient threshold and a preset solute concentration threshold in the extractant activity coefficient sequence and the solute concentration detection result sequence, and if so, obtain a first extractant addition instruction and a first period dynamic adjustment instruction; Based on the first extractant adding instruction, calling the extractant high-pressure spraying component to add the extractant into the extraction box; The first sampling detection period is shortened by one half based on the first period dynamic adjustment instruction to obtain an extractant activity sampling detection period and a solute concentration sampling detection period.

5. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 4, wherein: include: When there is no data less than or equal to a preset extractant activity coefficient threshold and a preset solute concentration threshold in the extractant activity coefficient sequence and the solute concentration test result sequence, traversing the extractant activity coefficient sequence and the solute concentration test result sequence to perform single-point gradient analysis to obtain an extractant activity coefficient gradient descending sequence and a solute concentration gradient descending sequence; performing an extractant activity coefficient trend analysis based on the extractant activity coefficient gradient descent sequence to obtain an extractant activity coefficient trend factor, and adjusting the first sampling detection period according to the extractant activity coefficient trend factor to obtain an extractant activity sampling detection period; A solute concentration trend analysis is performed based on the solute concentration gradient descending sequence to obtain a solute concentration trend factor, and the first sampling detection period is adjusted according to the solute concentration trend factor to obtain a solute concentration sampling detection period.

6. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 5, wherein: The extractant activity coefficient trend analysis is performed based on the extractant activity coefficient gradient descent sequence to obtain the extractant activity coefficient trend factor, including: Selecting a central gradient from a descending sequence of the extractant activity coefficient gradient, wherein the central gradient is the mode of the extractant activity coefficient gradients in the descending sequence of the extractant activity coefficient gradient; Taking the central gradient as the trend center, constructing a trend center neighborhood according to a preset trend radius; Calculating the trend center neighborhood density of the trend center neighborhood; Perform edge diffusion on the trend center neighborhood according to a preset diffusion bandwidth, and perform diffusion stop identification based on the density of the trend center neighborhood to determine the target trend center neighborhood; The mean of the neighborhood of the target trend center is calculated to obtain the extractant activity coefficient trend factor.

7. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 6, wherein: Performing edge diffusion on the trend center neighborhood according to a preset diffusion bandwidth, and performing diffusion stop identification based on the density of the trend center neighborhood to determine the target trend center neighborhood, including: Perform edge diffusion on the trend center neighborhood according to a preset diffusion bandwidth to obtain a diffusion trend center neighborhood; When the diffusion trend center neighborhood density of the diffusion trend center neighborhood is greater than or equal to the trend center neighborhood density, and the difference between the diffusion trend center neighborhood density and the trend center neighborhood density is less than or equal to a preset difference, the diffusion is stopped, and the diffusion trend center neighborhood is used as the target trend center neighborhood; When the diffusion trend center neighborhood density of the diffusion trend center neighborhood is less than the trend center neighborhood density, the trend center neighborhood is used as the target trend center neighborhood.

8. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 6, wherein: Calculating the mean of the neighborhood of the target trend center to obtain the extractant activity coefficient trend factor also includes: Determining whether the extraction agent activity coefficient trend factor meets a preset tolerance threshold, and if not, obtaining extraction abnormality warning information; An early warning is given to the extraction process according to the extraction abnormality early warning information.

9. The method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to claim 1, wherein: The preset requirement is that the fluctuation variance of the pH monitoring value is less than or equal to the preset fluctuation variance.

10. A high-purity rare earth metal recovery system for waste rare earth permanent magnet materials, characterized in that: A method for recovering high-purity rare earth metals from waste rare earth permanent magnet materials according to any one of claims 1 to 9, the system comprising: A processing module is used to mechanically crush the waste rare earth permanent magnet material into material particles, and perform acid leaching treatment on the material particles using a preset chemical solvent according to a preset leaching parameter group; A monitoring module is used to continuously monitor the pickling solution using a pH meter during the pickling process to obtain a pH monitoring value sequence; An analysis module is used to perform fluctuation trend analysis on the pH monitoring value sequence, and when the analysis result meets the preset requirements, the acid leaching solution is centrifuged to obtain a solution to be extracted; An extraction module, configured to add the solution to be extracted into an extraction box via a waste material adding assembly, add an extractant into the extraction box via an extractant high-pressure spraying assembly provided on the extraction box, and drive a first rotating assembly via a motor to rotate the extraction box at a first rotation speed for extraction; The detection module is used to dynamically and periodically detect the extraction process until the preset extraction stop condition is met, obtain the extraction solution, precipitate and crystallize the extraction solution, and wash and dry the precipitate to obtain high-purity rare earth metal salt; The smelting module is used to perform reduction smelting on the high-purity rare earth metal salt to obtain high-purity rare earth metal.

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