Process method for improving purity of cathode plate based on electrolytic copper refining process regulation

Abstract

This invention relates to the field of copper electrolytic refining control technology, and in particular to a process method for improving the purity of cathode plates based on the regulation of the electrolytic copper refining process. The method includes the following steps: S1, pre-treating the colloidal system charge state of the circulating electrolyte; S2, constructing a uniform mass transfer environment in the diffusion boundary layer on the cathode surface during the electrolysis start-up stage; S3, homogenizing and regulating the inter-electrode electric field; S4, simultaneously implementing in-situ interface barrier treatment in the electrolyte circulation path; S5, dynamically adjusting the cathode interface electrocrystallization environment in stages according to the electrolysis process to suppress the instantaneous potential shift disturbance of the oxygen evolution side reaction; S6, continuously implementing impurity co-deposition suppression intervention based on the difference in deposition potential between impurities and copper; S7, performing surface cleaning and maintenance treatment on the cathode plate to remove interface-adsorbed impurities and residual electrolyte, thereby obtaining a high-purity cathode copper plate. This invention significantly improves the continuous and stable operation capability of the electrolysis process and reduces rework and loss costs caused by product defects.

Description

Technical Field

[0001] This invention relates to the field of copper electrolytic refining control technology, and in particular to a process method for improving the purity of cathode plates based on the regulation of the electrolytic copper refining process. Background Technology

[0002] In electrochemical metallurgical systems, copper electrolytic refining uses pyrometallurgically refined crude copper as the anode, pure copper starting sheet or stainless steel plate as the cathode, and a copper sulfate-sulfuric acid mixed solution as the electrolyte. Under the action of a DC electric field, the copper at the anode undergoes electrochemical dissolution, and copper ions are reduced and deposited at the cathode, thus achieving a purification process that separates copper from impurities. With the development of fields such as electronic information, precision electrical engineering, and new energy materials, the purity requirements for cathode copper are constantly increasing, while the limits on impurities such as arsenic, antimony, bismuth, and lead are becoming increasingly stringent. According to the Nernst equation, diffusion boundary layer theory, and electrocrystallization kinetics theory, the purity of cathode deposition depends not only on the concentration of the host ions and macroscopic electrical parameters, but also on intrinsic factors such as the double-layer structure, impurity co-deposition behavior, colloidal stability, and interfacial mass transfer state. Conventional process control is insufficient to meet the theoretical and engineering requirements of high-purity electrodeposition.

[0003] The traditional process commonly used in the copper electrolytic refining industry is as follows: controlling macroscopic parameters such as copper ion concentration, free sulfuric acid concentration, electrolyte temperature, circulation flow rate and current density in the electrolyte, adding grain refiners such as gelatin, thiourea, and chloride ions, and removing soluble metal impurities by means of solvent extraction, ion exchange and filtration to achieve the production of conventional cathode copper.

[0004] In the process of high-purity copper electrolytic deposition, traditional control methods have obvious theoretical limitations: the ion concentration and pH value in the diffusion boundary layer are significantly different from those in the main electrolyte. Impurities such as antimony and bismuth are prone to hydrolysis reactions in the interface region to generate hydroxyl oxide colloids. These colloids have high specific surface area and interfacial activity, and are easy to undergo electrophoretic migration and adsorption on the cathode surface under the action of an electric field, forming mechanical inclusions and co-deposition.

[0005] Meanwhile, organic colloids and silica-alumina colloids formed by the decomposition of additives and the introduction of raw materials in the electrolyte cannot be effectively removed by conventional purification methods. This will damage the uniformity of cathode electrocrystallization and induce morphological defects such as dendrites and nodules.

[0006] Therefore, it can be seen that the above-mentioned methods in the existing technology have the following shortcomings in actual production processes:

[0007] First, the existing process only controls the main components of the electrolyte and macroscopic electrical parameters, which leads to abnormal co-deposition of impurities with similar potentials to copper, such as arsenic, antimony, and bismuth, forming lattice inclusions and colloidal inclusions, directly limiting the upper limit of the purity of the cathode plate.

[0008] Secondly, the existing technology's processing methods make it easy for colloidal particles to generate heterogeneous nucleation and inclusion on the cathode surface. At the same time, the lack of refined control over factors such as the uniformity of electric field distribution and current fluctuations leads to disordered cathode electrocrystallization kinetics, poor selective suppression of impurities, and insufficient product purity and stability.

[0009] Therefore, it is necessary to design a process method to improve the purity of the cathode plate by controlling the electrolytic copper refining process. Summary of the Invention

[0010] To solve one of the above-mentioned technical problems, the present invention adopts the following technical solution: a process method for improving the purity of cathode plates based on the control of electrolytic copper refining process, characterized by including the following steps: S1, pre-treating the colloidal system charge state of the circulating electrolyte, and achieving stable dispersion of inorganic hydroxyl colloids and organic degradation colloids in the electrolyte through interface charge compensation.

[0011] S2. After pretreatment, during the electrolysis start-up stage, a uniform mass transfer environment of diffusion boundary layer is constructed on the cathode surface to correct the Reynolds number distribution of the fluid in the near-wall region of the cathode and unify the material transfer conditions at the interface between the main electrolyte and the cathode.

[0012] S3. After starting the electrolytic deposition process, the electric field between the electrodes is homogenized and regulated to compensate for the ion flux deviation caused by microcracks in the anodic passivation film and to suppress local current distortion and deposition potential shift between the electrodes.

[0013] S4. During the electrolytic deposition process, in-situ interface barrier treatment is simultaneously implemented in the electrolyte circulation path to target and adsorb colloidal impurity particles in the electrolyte.

[0014] S5. After completing the inter-electrode electric field regulation in step S3, the electrocrystallization environment at the cathode interface is dynamically adjusted in stages according to the electrolysis process to suppress the instantaneous potential shift disturbance of the oxygen evolution side reaction and maintain the homogeneous nucleation and growth conditions of the deposited grains.

[0015] S6. During the entire electrolysis cycle, based on the electrocrystallization environment parameters fed back from step S5 and the difference in deposition potential between impurities and copper, continuous intervention to suppress impurity co-deposition is implemented to enhance the selective reduction deposition of copper ions. The data on the impurity suppression effect is synchronously transmitted back to the preprocessing module of step S1 to form a closed loop of full-process collaboration.

[0016] S7. After electrolysis, based on the barrier effect monitoring data fed back from step S4, the cathode plate is subjected to surface cleaning and maintenance treatment to remove interface adsorbed impurities and residual electrolyte, thereby obtaining a high-purity cathode copper plate.

[0017] As a preferred embodiment, the pretreatment of the charge state of the colloidal system in step S1 is as follows:

[0018] (1) Online detection of colloidal electrokinetic potential, ionic strength, relative content of organic degradation products and concentration of trace fluoride ions in circulating electrolyte, and comprehensive determination of the instability risk level of colloidal system;

[0019] (2) Based on the level of instability risk, charge regulators are added directionally to the electrolyte buffer tank to unify the surface charge state of colloidal particles to the preset negative charge range.

[0020] (3) Low-shear homogeneous disturbance is applied to the electrolyte in the buffer tank to eliminate local charge accumulation and colloidal agglomerates;

[0021] (4) Static homogenize the disturbed electrolyte and send it into the electrolytic cell system after the colloidal electric potential stabilizes; wherein, the static homogenization completion signal serves as the only pre-trigger condition for the start of electrolysis in step S2.

[0022] As a preferred solution, the in-situ interface barrier treatment in step S4 is as follows:

[0023] (1) At the front end of the liquid distributor of the electrolytic cell, colloidal impurities that are oppositely charged to the cathode surface are pre-adsorbed and retained;

[0024] (2) A filter-type interception structure is arranged in the inter-electrode barrier between the cathode and the anode to intercept micro- and nano-sized colloidal impurities step by step according to the particle size scale.

[0025] (3) Periodically perform micro-flow backwashing on the interception section of the filter-type interception structure;

[0026] (4) The impurity enrichment solution discharged from backwashing is introduced into an independent purification branch and is not returned to the main electrolyte circulation system;

[0027] (5) A particle concentration monitoring node is set downstream of the filter-type interception structure to monitor the penetration rate of colloidal impurities in real time. When the penetration rate exceeds the preset limit, the backwashing frequency and interception intensity are automatically adjusted. The penetration rate monitoring data in step (5) is used as the input parameters for the spray pressure and purging speed of the surface cleanliness maintenance treatment in step S7.

[0028] As a preferred approach, S2 constructs a uniform mass transfer environment in the cathode diffusion boundary layer, and is implemented according to the following steps:

[0029] (1) Before electrolysis is started, the fluid velocity in the near-wall region of the cathode working surface is calibrated point by point to obtain basic data on the near-wall Reynolds number distribution at different points on the entire cathode plate.

[0030] (2) After electrolysis is started, the concentration of trace fluoride ions, free hydrogen ions and copper ions in the main electrolyte are collected online and the real-time characteristic thickness of the cathode diffusion boundary layer is detected simultaneously.

[0031] (3) Substitute all the detection data collected in the above steps into the mass transfer equilibrium quantization model with near-wall Reynolds number correction, and calculate the mass transfer equilibrium coefficient at the corresponding time.

[0032] (4) Compare the calculated mass transfer equilibrium coefficient with the preset high-purity production equilibrium range, adjust the opening of the electrolyte inlet branch and the deflection angle of the inlet distributor according to the deviation range, correct the Reynolds number distribution in the cathode near-wall region, until the mass transfer equilibrium coefficient stably falls into the preset range.

[0033] (5) During the entire electrolysis process, the above detection, calculation and adjustment steps are repeated every 2 hours to dynamically maintain the stability of the mass transfer state of the cathode boundary layer throughout the process. The calculation results of each round are simultaneously pushed to the S3 inter-electrode electric field homogenization and S5 electrocrystallization environment adjustment steps.

[0034] As a preferred option, when the mass transfer equilibrium coefficient falls into the preset equilibrium range, the inter-electrode electric field homogenization and normalization operation of S3 is initiated, and the mass transfer equilibrium coefficient is used as the input variable of the electric field normalization intensity, so that the electric field distribution and the boundary layer mass transfer state are adapted in real time, and the electric field normalization intensity and the mass transfer equilibrium coefficient have a linear correspondence.

[0035] As a preferred approach, step S6, which involves impurity co-deposition suppression intervention, is implemented according to the following steps:

[0036] (1) During the electrolysis operation, the impedance characteristics and integrity of the passivation film on the anode surface are detected online, and the ion permeability coefficient of the microcracks in the anode passivation film is calculated by equivalent circuit fitting.

[0037] (2) By using a high-frequency and high-speed data acquisition system, the instantaneous fluctuation data of the inter-electrode potential is monitored in real time at a microsecond sampling interval, and the instantaneous potential shift coefficient caused by the oxygen evolution side reaction is separated and extracted.

[0038] (3) The real-time concentration of each controlled impurity in the electrolyte, the equilibrium precipitation potential of the corresponding impurity ions, the interfacial adsorption coefficient, and the real-time charge surface density data of the cathode interface are collected simultaneously. All parameters are substituted into the multi-impurity synergistic repulsion quantification model that couples the permeability of the anode microcrack and the instantaneous potential shift to calculate the comprehensive impurity repulsion coefficient at the corresponding time.

[0039] (4) Compare the calculated comprehensive impurity repulsion coefficient with the preset control threshold, and dynamically adjust the cathode interface charge density and the voltage regulation accuracy of the inter-electrode power supply according to the deviation amplitude to mitigate the risk of co-deposition caused by instantaneous potential shift. The adjustment command and the model calculation results are synchronized in real time to ensure that the instantaneous potential shift disturbance is mitigated within 100 microseconds.

[0040] (5) During the entire electrolysis cycle, the above parameters are continuously collected, calculated and controlled in a closed loop to maintain the continuous suppression effect on impurity co-deposition throughout the process. The calculation results of the entire cycle are simultaneously pushed to the S5 electrocrystallization environment adjustment step and the S1 colloidal system charge state pretreatment step to achieve closed-loop coordination throughout the entire process.

[0041] As a preferred embodiment, the uniformization and normalization of the inter-electrode electric field described in S3 includes uniformly calibrating the flatness and verticality of all anode plates in the same tank, uniformly normalizing the parallelism and inter-electrode spacing of the cathode plates, uniformly processing the overlapping surfaces of the conductive busbars to homogenize the contact resistance, and simultaneously monitoring the current distribution of a single electrode plate in zones to eliminate local current density distortion. The current distribution monitoring data is synchronously input into the multi-impurity cooperative repulsion quantization model in S6 as auxiliary correction parameters for model calculation.

[0042] As a preferred option, the segmented dynamic adjustment of the cathode interface electrocrystallization environment in S5 is specifically as follows: according to the initial nucleation-dominant stage, the middle stable growth stage, and the later thickening and forming stage, corresponding interface impedance adjustment strategies are set respectively. By controlling the fluid disturbance intensity and charge transport state in the near-cathode region, the grain nucleation rate and growth rate are maintained in a preset matching relationship in each stage. The parameters of the adjustment strategy in each stage are taken from the real-time calculation results of the multi-impurity synergistic repulsion quantization model in S6.

[0043] As a preferred embodiment, the surface cleanliness maintenance treatment described in S7 specifically includes:

[0044] Low-tension, low-flow-rate directional spraying is used to remove the electrolyte adhering to the cathode surface, followed by dry purging with inert gas to remove residual droplets and adsorbed colloidal impurities. The spraying pressure and purging airflow velocity are adaptively adjusted based on the monitoring results of colloidal impurity concentration downstream of the filter-type interception structure.

[0045] After the cleaning process is completed, the amount of residual impurities on the surface of the cathode plate is detected online. The detection results are simultaneously fed back to the process control steps of the entire process for optimization of process parameters in subsequent batches.

[0046] As a preferred approach, throughout the entire process from steps S1 to S7, the colloidal electrokinetic potential of the electrolyte, the thickness of the cathode diffusion boundary layer, and the regularity of the inter-electrode electric field are monitored online simultaneously. The mass transfer equilibrium coefficient calculated by the mass transfer equilibrium quantification model and the comprehensive impurity repulsion coefficient calculated by the multi-impurity synergistic repulsion quantification model are used together as feedback variables. The monitoring data and the calculated data are simultaneously input into the process control link to form a multi-parameter closed-loop synergistic control system.

[0047] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0048] 1. This invention achieves stable dispersion of inorganic hydroxyl colloids and organic degradation colloids in the electrolyte through charge state pretreatment of the colloidal system. Coupled with in-situ interface barrier treatment to directionally intercept impurity particles, and further combined with impurity co-deposition inhibition intervention, it suppresses impurity interference from both the source and process. At the same time, through segmented electrocrystallization environment adjustment, it ensures that the deposited grains are homogeneous and dense, effectively reducing the co-deposition probability of harmful impurities such as arsenic, antimony, and bismuth. The resulting cathode copper has a purity that meets the national standard for high-purity cathode copper, and the plate surface is free of defects such as black spots, pits, and nodules. The batch purity fluctuation range is significantly reduced, and the product quality stability is significantly better than that of traditional processes.

[0049] 2. This invention forms a closed-loop process from electrolyte pretreatment to cathode plate cleaning, with each process working in synergy and dynamically adapting to effectively compensate for sudden disturbances such as microcracks in the anode passivation film and instantaneous potential shifts, suppressing local current distortion, avoiding overall production anomalies caused by fluctuations in a single process, significantly improving the continuous and stable operation capability of the electrolysis process, and reducing rework and loss costs caused by product defects.

[0050] 3. This invention compensates for ion flux deviations by homogenizing and regularizing the inter-electrode electric field, reducing energy loss caused by local current distortion. Simultaneously, segmented electrocrystallization regulates and smooths oxygen evolution side reactions, reducing energy waste caused by these side reactions. Compared to traditional processes, this effectively reduces electrolysis energy consumption. The in-situ interface barrier treatment utilizes an existing multi-stage interception structure to achieve targeted interception and adsorption of colloidal impurities, eliminating the need for large amounts of additional purification agents, reducing agent consumption and subsequent wastewater treatment pressure. Furthermore, the intercepted impurity enrichment solution can undergo sulfide precipitation treatment through an independent branch, avoiding pollution of the main electrolyte circulation system and reducing pollutant emissions. Closed-loop control throughout the entire process optimizes the consumption of charge regulators, electrolytes, and other materials, further reducing production costs and improving the company's economic efficiency and environmental compliance.

[0051] 4. The process steps of this invention are based on the equipment foundation design of existing electrolytic copper refining production lines. Colloidal pretreatment can be completed in existing electrolyte buffer tanks. Boundary layer construction can be achieved by adjusting existing electrolyte inlet distributors. Electrode field regularization can be completed by conventional calibration and polishing equipment. In-situ interface barrier structures can be directly installed in the existing electrolytic cell's inter-electrode barrier without the need for new large-scale special equipment. The modification difficulty is low and the cost is controllable.

[0052] Meanwhile, the process parameters of this invention can be flexibly adjusted according to the capacity of different production lines and the impurity content of raw materials, adapting to the production needs of high-purity cathode copper of different scales. It is suitable for both newly built high-purity electrolytic copper production lines and the upgrading and transformation of existing production lines, enabling rapid industrialization and having broad application prospects. Attached Figure Description

[0053] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or components are generally identified by similar reference numerals. In the drawings, the elements or components are not necessarily drawn to scale.

[0054] Figure 1 This is a schematic diagram of the layout of the multi-level interception structure of the present invention.

[0055] Figure 2 This is a schematic diagram of the process for improving the purity of the cathode plate based on the electrolytic copper refining process control of the present invention.

[0056] Figure 3 This is a schematic diagram of the pretreatment process for the charge state of the colloidal system according to the present invention.

[0057] In the diagram, 1 is the first filter plate; 2 is the second filter plate; and 3 is the third filter plate. Detailed Implementation

[0058] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and are therefore merely examples and should not be used to limit the scope of protection of the present invention. The specific structure of the present invention is as follows: Figures 1-3 As shown in the image.

[0059] Example 1: A method for improving the purity of the cathode plate by controlling the electrolytic copper refining process, including the following steps:

[0060] S1. The colloidal system charge state pretreatment of the circulating electrolyte is coupled to suppress the double-layer compression effect of trace fluoride ions, and the steady-state dispersion of inorganic hydroxyl colloids and organic degradation colloids in the electrolyte is achieved through interfacial charge compensation.

[0061] S2. After completing the pretreatment in step S1, during the electrolysis start-up stage, a uniform mass transfer environment with a diffusion boundary layer is constructed on the cathode surface. The pretreatment results of step S1 are simultaneously used as the prerequisite conditions for the boundary layer construction in step S2, correcting the Reynolds number distribution of the fluid in the near-wall region of the cathode, and unifying the material transfer conditions at the interface between the main electrolyte and the cathode. The mass transfer environment parameters are simultaneously used as the prerequisite input conditions for the uniformization and regularization step of the interelectrode electric field in step S3.

[0062] S3. After starting the electrolytic deposition process, the electric field between the electrodes is homogenized and regulated to compensate for the ion flux deviation caused by microcracks in the anodic passivation film, suppress local current distortion and deposition potential shift between the electrodes, and the electric field regulation result is synchronously fed back to the electrocrystallization environment adjustment step in step S5.

[0063] S4. During the electrolytic deposition process, in-situ interface barrier treatment is simultaneously implemented in the electrolyte circulation path to target and adsorb colloidal impurity particles in the electrolyte. The barrier effect monitoring data is simultaneously used as the input parameter for the surface cleanliness maintenance treatment step in step S7.

[0064] S5. After completing the inter-electrode electric field regulation in step S3, the cathode interface electrocrystallization environment is dynamically adjusted in stages according to different stages of the electrolysis process to suppress the instantaneous potential shift disturbance of the oxygen evolution side reaction and maintain the homogeneous nucleation and growth conditions of the deposited grains.

[0065] S6. During the entire electrolysis cycle, based on the electrocrystallization environment parameters fed back from step S5 and the difference in deposition potential between impurities and copper, continuous intervention to suppress impurity co-deposition is implemented to enhance the selective reduction deposition of copper ions. The data on the impurity suppression effect is synchronously transmitted back to the preprocessing module of step S1 to form a closed loop of full-process collaboration.

[0066] S7. After electrolysis, based on the barrier effect monitoring data fed back from step S4, the cathode plate is subjected to surface cleaning and maintenance treatment to remove interface adsorbed impurities and residual electrolyte, thereby obtaining a high-purity cathode copper plate.

[0067] Further explanation is needed regarding this scheme, which designs a complete process from electrolyte pretreatment before electrolysis production, to cathode interface boundary layer construction during electrolysis startup, to electric field homogenization control, in-situ interception of colloidal impurities, dynamic adjustment of the electrocrystallization environment, and suppression of impurity co-deposition throughout the entire electrolysis cycle, culminating in cathode plate surface cleaning after the electrolysis cycle. This process is compatible with existing copper electrolysis production lines. All process parameters involved in each step of this scheme are based on clear current national standards and non-ferrous metal industry specifications: for example, the control limit for trace fluoride ions is determined according to the "Industry Specification for Impurity Control in Electrolytes for Heavy Non-ferrous Metals Metallurgy," the standard for electrode spacing is determined according to the "Design Specification for Non-ferrous Metals Metallurgical Engineering," and the characteristic thickness of the cathode diffusion boundary layer is determined according to the general design standard for electrochemical engineering. Those skilled in the art can directly determine the reasonable range of parameter values ​​based on publicly available specifications.

[0068] In this scheme, the colloidal steady-state dispersion treatment completed in S1 directly determines the initial environment of the cathode boundary layer in S2, avoiding interfacial mass transfer inhomogeneity caused by colloidal agglomeration; the uniform mass transfer environment constructed in S2 provides a stable precondition for the electric field regularization in S3, avoiding the superposition effect of mass transfer inhomogeneity and electric field distortion; the electric field homogenization treatment completed in S3 directly affects the stability of cathode electrocrystallization in S5, avoiding abnormal grain growth caused by local current distortion; the interfacial barrier effect in S4 directly determines the process parameters of the cleaning treatment in S7, avoiding surface contamination caused by colloidal residue; the electrocrystallization environment parameters in S5 directly affect the effect of impurity co-deposition suppression in S6, avoiding crystallization defects from providing adsorption sites for impurities; the impurity suppression effect in S6 is also synchronously fed back to the pretreatment module in S1, realizing dynamic optimization of the entire process.

[0069] To further explain, the preparation of high-purity cathode copper lies in controlling the electrocrystallization process at the cathode interface. This scheme inhibits the migration of impurities to the cathode interface, stabilizes the microenvironment for electrocrystallization at the interface, blocks the path of impurity co-deposition, and ultimately improves the purity of the cathode plate.

[0070] It should be noted that those skilled in the art have long attributed the insufficient purity of cathode plates to the overall high concentration of impurities in the electrolyte, while generally ignoring influencing factors such as double-layer compression caused by trace amounts of fluoride ions, sudden release of impurities caused by microcracks in the anolyte passivation film, and instantaneous potential shifts caused by oxygen evolution side reactions. Although these factors are present in low concentrations and occur over short periods, they are the cause of batch purity fluctuations and surface black spots and pitting in high-purity copper production. This solution incorporates these factors into the routine control scope. At the same time, this solution achieves precise quantitative control of the micro-environment at the cathode interface. The diffusion boundary layer on the cathode surface, only tens of micrometers thick, is the site of electrocrystallization reactions, and its ion concentration and acidity differ greatly from those of the main electrolyte. This solution, through a mass transfer equilibrium quantitative model coupled with near-wall Reynolds number correction, transforms the mass transfer state of the boundary layer into quantifiable and controllable process parameters, realizing a shift from extensive macro-control to precise micro-area management.

[0071] Furthermore, this solution achieves dynamic suppression of synergistic co-deposition of multiple impurities. Harmful impurities such as arsenic, antimony, and bismuth exhibit significant synergistic co-evolution effects, and the risk of co-deposition when all three coexist is far higher than when they exist alone. Existing technologies can only control the concentration of a single impurity and cannot address the synergistic effects of multiple impurities. This solution utilizes a multi-impurity synergistic repulsion quantification model, assigning weights based on national standard impurity limits, and coupling the deposition potential, interfacial adsorption characteristics, and interfacial charge density of impurities for calculation, achieving dynamic prediction and precise suppression of synergistic co-deposition of multiple impurities. Finally, various process parameters in the electrolysis process dynamically influence each other; fluctuations in one parameter can trigger a chain reaction of changes in others. This solution uses the feedback loop between each step, using the output of the preceding step as the input of the subsequent step, while simultaneously feeding back the effects of the subsequent step to the preceding module, forming a complete closed-loop control system and achieving stable and controllable operation throughout the entire electrolysis process.

[0072] As a preferred embodiment, the pretreatment of the charge state of the colloidal system in step S1 is as follows:

[0073] (1) Online detection of colloidal electrokinetic potential, ionic strength, relative content of organic degradation products and concentration of trace fluoride ions in circulating electrolyte, and comprehensive determination of the instability risk level of colloidal system;

[0074] (2) Based on the level of instability risk, charge regulators are added directionally to the electrolyte buffer tank to unify the surface charge state of colloidal particles to the preset negative charge range.

[0075] (3) Low-shear homogeneous disturbance is applied to the electrolyte in the buffer tank to eliminate local charge accumulation and colloidal agglomerates;

[0076] (4) Static homogenize the disturbed electrolyte and send it into the electrolytic cell system after the colloidal electric potential stabilizes; wherein, the static homogenization completion signal serves as the only pre-trigger condition for the start of electrolysis in step S2.

[0077] Further explanation is needed regarding the detection parameters involved in step (1). The detection methods are all conventional detection methods known in the field. Specifically, the detection of colloidal electromotive potential adopts the electrophoretic light scattering method commonly used in the field, and the detection equipment is a ζ-potential analyzer commonly used in the industry. The detection basis is the test standard commonly used in the field of colloidal chemistry. The detection of ionic strength is achieved by the conventional conductivity method in the field. The detection equipment is an industrial online conductivity meter, and the detection basis is the national standard method for the detection of electrolytes in aqueous solutions. The detection of the relative content of organic degradation products adopts the conventional ultraviolet-visible spectrophotometry method in the field, corresponding to the characteristic absorption wavelength of the electrolytic additive. The detection method is the standard for the detection of organic matter in electrolytes commonly used in the non-ferrous metallurgical industry. The detection of trace fluoride ion concentration adopts the conventional ion-selective electrode method in the field. The detection equipment is an industrial online fluoride ion detector, and the detection basis is the national standard for the detection of fluoride ions in water quality.

[0078] The rules for determining the instability risk level of the colloidal system in step (1) are further explained in conjunction with the well-known DLVO colloidal stability theory in this field. The stability of the colloidal system depends on the electrokinetic potential of the colloidal particles. When the absolute value of the zeta potential is less than 30mV, the repulsive force between the colloidal particles is insufficient to overcome the van der Waals force, and aggregation instability will occur. At the same time, the increase in ionic strength, the increase in the concentration of trace fluoride ions, and the increase in the content of organic degradation products will all compress the double layer of the colloidal system and exacerbate the instability risk. Therefore, the instability risk level of this scheme is divided into three levels:

[0079] The low-risk level is defined as an absolute value of ζ potential ≥ 40mV, and all other parameters are within the limits specified in industry standards.

[0080] The medium risk level is defined as an absolute value of the ζ potential between 30mV and 40mV, or any parameter exceeding the industry standard limit.

[0081] A high-risk level is defined as an absolute value of the zeta potential <30mV, or multiple parameters exceeding industry-standard limits.

[0082] The charge regulator in step (2) is a commonly used anionic surfactant, specifically a compound of sodium lignosulfonate, gelatin, and thiourea, a conventional electrolytic additive. This type of regulator is itself a grain refiner commonly used in electrolytic copper refining and will not introduce new harmful impurities into the electrolyte. The dosage is determined according to the instability risk level. No dosage is required for low-risk levels, the dosage is 5-10 mg / L for medium-risk levels, and the dosage is 10-20 mg / L for high-risk levels. The dosage range is determined according to the specifications for the use of electrolyte additives in the non-ferrous metallurgical industry. Those skilled in the art can directly determine the corresponding dosage based on the risk level. The low-shear homogeneous disturbance in step (3) has a shear rate controlled at 50-100 s. -1This rate range achieves homogeneous mixing of the electrolyte without damaging the adsorption layer on the surface of the colloidal particles, thus avoiding secondary aggregation. The disturbance time is controlled within 30-60 minutes.

[0083] The static homogenization in step (4) allows the surface charge state of the colloidal particles to reach a stable equilibrium. The static homogenization time is controlled between 60 and 120 minutes until the ζ potential fluctuation amplitude of three consecutive tests does not exceed 5mV, at which point the homogenization is considered complete. At the same time, this scheme clarifies that the static homogenization completion signal is the only pre-trigger condition for the start of S2 electrolysis, ensuring that the colloidal system of the electrolyte is always in a stable state before the start of electrolysis, thus avoiding purity problems caused by colloidal impurities.

[0084] It should be noted that this solution is based on the DLVO colloidal stability theory. Starting from the charge characteristics of colloidal particles, it achieves precise control over the stability of the colloidal system and blocks the migration path of colloidal impurities to the cathode interface from the source.

[0085] Specifically, the multi-parameter online detection in step (1) and the risk level-oriented regulation in step (2) form a synergy of precise identification and targeted regulation. By simultaneously detecting the four parameters that affect the stability of the colloid, the risk of instability is comprehensively determined, and then the regulator is added in a targeted manner according to the risk level. This avoids the problem of blindly adding additives in the prior art, ensuring the regulation effect and preventing new problems caused by excessive additives.

[0086] The addition of charge regulator in step (2) and the low-shear homogenization disturbance in step (3) form a synergy of surface modification and uniform dispersion. The charge regulator makes the surface charge state of colloidal particles tend to be uniform, and the low-shear disturbance achieves homogeneous mixing of the entire electrolyte system, avoiding agglomeration caused by local charge accumulation. The two work together to achieve uniform dispersion of the colloidal system.

[0087] The homogenization disturbance in step (3) and the static homogenization in step (4) form a synergy of dynamic mixing and static equilibrium. Dynamic mixing allows the regulator to be evenly distributed in the electrolyte, and static homogenization allows the surface charge state of the colloidal particles to reach a stable equilibrium, ensuring that the colloidal state of the electrolyte entering the electrolytic cell remains stable throughout the process.

[0088] The static homogenization completion signal in step (4) and the electrolysis start-up in step S2 form a synergy of pre-verification and subsequent triggering. Electrolysis can only be started after the colloidal system reaches a stable state, which fundamentally avoids the cathode inclusion problem caused by colloidal instability.

[0089] It should be noted that when the potential of colloidal particles reverses to positive, they are strongly adsorbed by the negatively charged cathode and directly embedded in the deposition layer, forming inclusion defects. This solution predicts instability risks in advance by detecting the electrokinetic potential of the colloid online, and then maintains the stable negative charge of the colloid through charge compensation, eliminating the driving force for the colloid to migrate to the cathode. Secondly, this solution effectively suppresses the double-layer compression effect of trace fluoride ions. Even trace fluoride ions in the electrolyte, even at a concentration as low as 1 mg / L, can drastically compress the double layer of colloidal particles, significantly reducing the electrokinetic potential of the colloid and causing colloidal aggregation. Fluoride ions mainly come from trace fluoride impurities in the anode copper, which is an unavoidable component in the electrolytic copper refining system. This solution incorporates the fluoride ion concentration into the parameter for judging the instability risk of the colloid, and compensates for the double-layer compression effect caused by fluoride ions by the targeted addition of charge regulators, maintaining the stability of the colloid's electrokinetic potential.

[0090] In addition, this solution clarifies that the static homogenization completion signal is the only pre-trigger condition for electrolysis start-up, realizing the interlocking control of the two processes, avoiding errors from human operation, and ensuring that the colloidal system of the electrolyte is in a stable state before each batch of electrolysis starts.

[0091] As a preferred solution, the in-situ interface barrier treatment in step S4 is as follows:

[0092] (1) At the front end of the liquid distributor of the electrolytic cell, colloidal impurities that are oppositely charged to the cathode surface are pre-screened and pre-adsorbed and retained.

[0093] (2) A filter-type interception structure is arranged in the inter-electrode barrier between the cathode and the anode to intercept micro- and nano-sized colloidal impurities step by step according to the particle size scale.

[0094] (3) Periodically backwash the interception section of the filter-type interception structure with a small flow rate to prevent the intercepted impurities from being compacted, blocked, and released again;

[0095] (4) The impurity enrichment solution discharged from backwashing is introduced into an independent purification branch and is not returned to the main electrolyte circulation system;

[0096] (5) A particle concentration monitoring node is set downstream of the filter-type interception structure to monitor the penetration rate of colloidal impurities in real time. When the penetration rate exceeds the preset limit, the backwashing frequency and interception intensity are automatically adjusted. The penetration rate monitoring data in step (5) is used as the input parameters for the spray pressure and purging speed of the surface cleanliness maintenance treatment in step S7.

[0097] Further explanation is needed regarding step (1), where an existing charged pre-screening section is installed at the front end of the electrolyte distributor in the electrolytic cell. Simultaneously, it is ensured that all electrolyte entering the electrolytic cell must pass through the installed charged pre-screening section. The structure of the charged pre-screening section is a porous conductive material known in the art, specifically a lead-antimony alloy porous plate, a graphite porous plate, or other corrosion-resistant conductive materials commonly used in electrolytic systems. The pore size of the porous plate is controlled at 5-10 mm, and the porosity is controlled at 40%-60%. The parameter range is determined according to the design specifications for fluid distributors in the non-ferrous metallurgical industry. The potential of the charged pre-screening section is controlled within the same negative potential range as the cathode, thus enabling electrostatic adsorption of positively charged colloidal impurities, achieving pre-adsorption and retention. Its potential control accuracy is ±10 mV, determined according to industry standards for potential control in electrolytic systems. Those skilled in the art can complete the installation of the charged pre-screening section based on the above description.

[0098] The filter-type interception structure in step (2) is positioned within the inter-electrode barrier between the cathode and anode. The inter-electrode barrier is a conventional baffle structure in existing electrolytic cells, used to prevent short circuits between the cathode and anode. This solution simply integrates the filter-type interception structure based on the existing inter-electrode barrier, without modifying the main structure of the electrolytic cell. The multi-stage filter-type interception structure is divided into three stages, with pore sizes of 100μm, 50μm, and 10μm respectively from the liquid inlet end to the cathode side (corresponding to...). Figure 1 The existing technology uses a first filter plate 1, a second filter plate 2, and a third filter plate 3 to form a graded interception system with gradient pore sizes. The pore size classification is determined according to industry standards for micro and nanoparticle filtration. The filter-type interception structure is made of corrosion-resistant and electrolyte-resistant polymer materials such as polytetrafluoroethylene and polypropylene, which are well-known in the art. It is suitable for the electrolytic copper refining environment of sulfuric acid system and does not introduce new impurities into the electrolyte. Those skilled in the art can complete the layout of the filter-type interception structure according to the above pore size classification and material requirements.

[0099] The periodic micro-flow backwashing in step (3) uses purified clean electrolyte as the backwashing medium. The backwashing flow rate is controlled at 5%-10% of the normal inlet flow rate, and the backwashing pressure is controlled at 0.1-0.2 MPa. This parameter range can achieve the removal of impurities through rinsing without interfering with the normal flow field distribution in the electrolytic cell. The backwashing cycle is controlled at 4-8 hours and dynamically adjusted according to the penetration rate monitoring data in step (5). The backwashing control method is the electromagnetic valve timing control known in the art. The particle concentration monitoring node in step (5) is located downstream of the multi-stage filter interception structure and upstream of the cathode surface to ensure real-time monitoring of the concentration of colloidal impurities in the electrolyte after interception. The particle concentration monitoring uses a conventional online laser particle counter, which covers particles from 10nm to 100μm and can detect the concentration of micro-nano colloidal particles. The penetration rate is calculated by dividing the particle concentration downstream of the filter interception structure by the particle concentration upstream. The preset limit is 10%. That is, when the penetration rate exceeds 10%, the backwashing frequency is automatically increased, for example, from once every 8 hours to once every 4 hours. At the same time, the interception intensity can be increased by adjusting the inlet flow rate. In addition, this solution clarifies that the penetration rate monitoring data is synchronously used as the input parameter for the S7 surface cleanliness maintenance treatment. That is, when the penetration rate is high, it indicates that there are more residual colloidal impurities in the electrolyte. The spray pressure and purging speed are increased accordingly to ensure the surface cleanliness effect.

[0100] The multi-stage filter-type interception structure in step (2) and the periodic micro-flow backwashing in step (3) form a continuous interception-online cleaning system. The multi-stage filter-type interception structure achieves continuous impurity retention, and the micro-flow backwashing achieves online cleaning of the filter-type interception structure. This ensures the continuity of the interception effect and avoids the flow field disturbance caused by the blockage of the filter-type interception structure, thus achieving long-term stable operation of the interception system. The online penetration rate monitoring in step (5) forms a synergy of real-time monitoring, dynamic control, and full-process adaptation with the preceding interception and backwashing steps and the subsequent cleaning treatment steps. The interception effect is grasped in real time through online monitoring, and the backwashing frequency and interception intensity are dynamically adjusted. At the same time, the monitoring data is synchronized to the subsequent cleaning treatment process.

[0101] As a preferred approach, S2 constructs a uniform mass transfer environment in the cathode diffusion boundary layer, and is implemented according to the following steps:

[0102] (1) Before electrolysis is started, a laser Doppler velocimeter is used to calibrate the fluid velocity in the near-wall region of the cathode working surface point by point to obtain basic data on the near-wall Reynolds number distribution at different points on the entire cathode plate.

[0103] (2) After the electrolysis is started, the concentration of trace fluoride ions, free hydrogen ions and copper ions in the main electrolyte are collected online and synchronously. The real-time characteristic thickness of the cathode diffusion boundary layer is detected by electrochemical impedance spectroscopy.

[0104] (3) Substitute all the detection data collected in the above steps into the mass transfer equilibrium quantification model with near-wall Reynolds number correction, and calculate the mass transfer equilibrium coefficient at the corresponding time. The model calculation link is seamlessly connected with the existing DCS control system of the electrolysis production line. The sampled data is directly input into the model without intermediate conversion links.

[0105] (4) Compare the calculated mass transfer equilibrium coefficient with the preset high-purity production equilibrium range, adjust the opening of the electrolyte inlet branch and the deflection angle of the inlet distributor according to the deviation range, correct the Reynolds number distribution in the cathode near-wall region, until the mass transfer equilibrium coefficient stably falls into the preset range, and the adjustment action is linked with the model calculation result in real time without lag deviation.

[0106] (5) During the entire electrolysis process, the above detection, calculation and adjustment steps are repeated every 2 hours to dynamically maintain the stability of the mass transfer state of the cathode boundary layer throughout the process. The calculation results of each round are simultaneously pushed to the S3 inter-electrode electric field homogenization and S5 electrocrystallization environment adjustment steps to achieve multi-process coordinated control.

[0107] The expression for the mass transfer equilibrium quantization model coupled with near-wall Reynolds number correction is:

[0108]

[0109] In the formula:

[0110] The mass transfer equilibrium coefficient is dimensionless and its reasonable range is determined according to the non-ferrous metallurgical engineering design specifications.

[0111] The symbol for the closed surface integral along the effective deposition area of ​​the cathode;

[0112] The modulus of the copper ion concentration gradient in the electrolyte;

[0113] The characteristic thickness of the cathode diffusion boundary layer is determined according to the general design standards for electrochemical engineering.

[0114] This is the Reynolds number correction factor for the cathode near-wall region, determined based on the standard definition of wall flow in fluid mechanics and field calibration data.

[0115] The area of ​​a micro-element of the cathode working surface;

[0116] The diffusion coefficient of copper ions in the electrolyte is determined according to national standards.

[0117] It is a natural exponential function;

[0118] This is a dimensionless correction factor for the effect of acidity, set according to the industry standard YS / T1057 for copper electrolysis electrolyte systems.

[0119] The concentration of trace fluoride ions in the electrolyte is limited according to the industry standard for impurity control of electrolytes in heavy non-ferrous metal metallurgy.

[0120] The concentration of free hydrogen ions in the main electrolyte;

[0121] The effective deposition area of ​​the cathode is determined according to industry standards for electrolytic cell structure design.

[0122] The calculation result of the mass transfer equilibrium coefficient is simultaneously used as a preliminary judgment basis for the uniformity and regularization of the electric field between electrodes of S3.

[0123] It needs further explanation that the mass transfer equilibrium quantification model with coupled near-wall Reynolds number correction adopted in this scheme has a three-layer standard architecture. Specifically, the first layer of the model is the data acquisition input layer. The input parameters are divided into two categories: one is the basic parameters obtained through calibration before electrolysis, including the total effective deposition area of ​​the cathode. Cathode near-wall region Reynolds number correction factor The first type is basic distribution data; the second type is real-time parameters collected online during the electrolysis process, including the model of copper ion concentration gradient. Characteristic thickness of cathode diffusion boundary layer Copper ion diffusion coefficient Acidity influence correction factor Trace fluoride ion concentration The concentration of free hydrogen ions in the main electrolyte All input parameters are physical quantities that can be directly obtained at the electrolytic copper production site using known equipment and testing methods. Among them, the laser Doppler velocimeter is a well-known flow velocity measurement device in the field of fluid mechanics, capable of point-by-point calibration of the fluid velocity in the near-wall region of the cathode. The near-wall Reynolds number is calculated according to the standard definition of wall flow in fluid mechanics: Reynolds number = fluid density × characteristic velocity × characteristic length / dynamic viscosity. Those skilled in the art can calculate the near-wall Reynolds number correction factor based on the calibrated flow velocity data. The electrochemical impedance spectroscopy is a well-known boundary layer thickness detection method in the field of electrochemistry. By fitting the diffusion impedance in the electrochemical impedance spectrum, the real-time characteristic thickness of the cathode diffusion boundary layer can be calculated. This method is a conventional detection technique known to those skilled in the art. The copper ion diffusion coefficient is determined according to the national standard GB / T27508 "Determination of Diffusion Coefficient of Electrolytes in Aqueous Solutions". The copper ion diffusion coefficient at different temperatures and concentrations can be obtained by referring to tables or calculating using the methods in this standard. The acidity influence correction factor... According to the industry standard YS / T1057 "Technical Specification for Copper Electrolytic Refining Electrolyte" for copper electrolysis electrolyte systems, the standard specifies the methods for correcting the mass transfer characteristics of the electrolyte under different acidities. The value range is 0.8-1.2, adjusted in real time according to the acidity of the main electrolyte; the limit for trace fluoride ion concentration is based on the industry standard for impurity control of electrolytes in heavy non-ferrous metal metallurgy, with a control limit of ≤5mg / L; the free hydrogen ion concentration in the main electrolyte is determined based on the conventional process range of copper electrolytic refining, which is 180-220g / L. The second layer of the model is the computational layer, where the closed surface integral is the integral operation of the entire effective deposition area of ​​the cathode. It is used to integrate and average the parameters of the entire cathode plate surface, eliminating the influence of local parameter fluctuations and ensuring that the calculated mass transfer equilibrium coefficient can reflect the average mass transfer state of the entire cathode surface. All parameters in the input layer are directly entered into the computational layer for calculation, and a unique mass transfer equilibrium coefficient is output. .

[0124] The third layer of the model is the execution output layer. The mass transfer equilibrium coefficient output by the model directly corresponds to two execution actions. The first is to adjust the opening degree of the electrolyte inlet branch pipe and the deflection angle of the inlet distributor to correct the Reynolds number distribution in the near-wall region of the cathode and realize closed-loop control of the boundary layer mass transfer state. The second is to simultaneously push it to the S3 inter-electrode electric field homogenization and S5 electrocrystallization environment adjustment steps to realize the coordinated control of multiple processes. The algorithm features are deeply bound to the process technology features of electrolytic refining. The output of the model directly drives the process actions and solves the technical problems of impurity hydrolysis and co-deposition caused by uneven mass transfer in the cathode boundary layer.

[0125] This solution clarifies the temporal logic and linkage relationships between steps. Pre-electrolysis calibration is the foundation for all subsequent adjustments; only by completing point-by-point calibration of the near-wall Reynolds number can accurate Reynolds number distribution correction be achieved during electrolysis. Online data acquisition is a prerequisite for model calculation; all acquired data is synchronously input into the model without intermediate conversion steps, ensuring real-time data accuracy. Model calculation results directly drive process adjustments, with adjustments and calculation results linked in real-time without lag or deviation, ensuring timely control. The entire process is repeated every 2 hours, achieving dynamic stability throughout the electrolysis process. Simultaneously, the calculation results from each round are synchronously pushed to other processes, enabling coordinated control across multiple processes.

[0126] Further explanation based on well-known electrochemical mass transfer theory in this field: The cathode diffusion boundary layer is a liquid film layer with a thickness of only tens of micrometers on the cathode surface, which is the reaction site for the reduction and deposition of copper ions. Due to the consumption of copper ions by the electrochemical reaction, the concentration of copper ions in the boundary layer is much lower than that of the main electrolyte, and the acidity is also much lower than that of the main electrolyte. This difference in concentration and acidity will cause impurity ions such as arsenic, antimony, and bismuth to hydrolyze in the boundary layer, generating hydroxyl colloids, which are directly adsorbed on the cathode surface, forming inclusion defects. The mass transfer state in the boundary layer is directly determined by the fluid flow state in the near-wall region of the cathode, that is, the near-wall Reynolds number. Existing technologies ignore the influence of the near-wall Reynolds number on the mass transfer state of the boundary layer, and there is no quantitative control method for the mass transfer state of the boundary layer. This scheme transforms the mass transfer state of the boundary layer into a quantifiable and controllable parameter through a mass transfer equilibrium quantitative model. By correcting the near-wall Reynolds number distribution, the precise control of the mass transfer state of the boundary layer is achieved.

[0127] It should be noted that this scheme is the first to deeply integrate fluid dynamics wall flow theory with electrochemical mass transfer theory, and construct a quantitative control system for the cathode diffusion boundary layer. It revolves around the cathode boundary layer, the site of the electrocrystallization reaction. In the existing technology, the mass transfer control of electrolytic copper refining is concentrated on adjusting macroscopic parameters such as the overall circulation flow rate, temperature, and copper ion concentration of the electrolyte. Those skilled in the art have overlooked the fact that there are great differences in the near-wall flow velocity at different points on the cathode plate, which will lead to uneven mass transfer in the local boundary layer and cause local impurity hydrolysis and co-deposition. This scheme directly controls the micro-area mass transfer state of the cathode boundary layer. The near-wall Reynolds number calibration in step (1) and the Reynolds number distribution correction in step (4) form a synergy of basic calibration and precise control. By calibrating point by point before electrolysis, the basic data of the near-wall flow state of the entire cathode plate are obtained. Then, based on the model calculation results, the opening of the inlet branch pipe and the deflection angle of the inlet distributor are precisely adjusted to correct the near-wall Reynolds number at different points and realize the homogenization of the mass transfer state of the entire cathode plate. The two work together to realize the overall The design of flow rate adjustment to point-by-point flow state correction; Steps (2) and (3) collect all parameters affecting the mass transfer state of the boundary layer online, input them into the model for calculation, and output the mass transfer equilibrium coefficient that can directly reflect the mass transfer state, realizing the real-time quantitative characterization of the mass transfer state of the boundary layer, solving the problem that the existing technology cannot quantify the mass transfer state of the boundary layer; The model calculation in step (3) and the process adjustment in step (4) cooperate with each other to realize the precise closed-loop control of the mass transfer state of the boundary layer; The full-process dynamic maintenance in step (5) and the collaboration of S3 and S5 processes push the model calculation results of each round to the electric field regularization and electrocrystallization adjustment processes, so that the electric field state, crystallization environment and boundary layer mass transfer state are adapted in real time, avoiding the superposition effect of mass transfer inhomogeneity and electric field distortion, realizing the synergistic effect of multiple processes. The algorithm features are not abstract calculations independent of the process steps, but are integrated into the entire process of process control, providing a precise quantitative basis for process adjustment, directly improving the deposition uniformity and purity stability of the cathode plate, and making a substantial contribution to the technical solution.

[0128] As a preferred option, when the mass transfer equilibrium coefficient falls into the preset equilibrium range, the inter-electrode electric field homogenization and normalization operation of S3 is initiated, and the mass transfer equilibrium coefficient is used as the input variable of the electric field normalization intensity, so that the electric field distribution and the boundary layer mass transfer state are adapted in real time. The electric field normalization intensity and the mass transfer equilibrium coefficient have a linear correspondence, and the correspondence is determined according to the non-ferrous metallurgical engineering design specifications.

[0129] It needs to be further explained that the uniformization and normalization operation of the interelectrode electric field will only be initiated when the mass transfer equilibrium coefficient falls into the preset equilibrium range, that is, when the boundary layer mass transfer state reaches a stable and uniform state. This is because the effect of electric field normalization can only be guaranteed when the interface mass transfer state is stable. Otherwise, the mass transfer inhomogeneity and electric field distortion will superimpose each other, which will exacerbate the abnormality of the interface reaction.

[0130] The preset equilibrium range of the mass transfer equilibrium coefficient is determined based on the non-ferrous metal metallurgical engineering design specifications and industry practices in the production of high-purity cathode copper. Specifically, the preset range of the mass transfer equilibrium coefficient is 0.8-1.2. When the mass transfer equilibrium coefficient is within this range, it indicates that the mass transfer state of the entire cathode plate is in a uniform and stable state, the ion concentration gradient and acidity distribution in the boundary layer are uniform, and there will be no local hydrolysis and enrichment of impurities. When the mass transfer equilibrium coefficient is less than 0.8 or greater than 1.2, it indicates that there is a problem of local mass transfer unevenness on the cathode plate. It is necessary to adjust the mass transfer state of the boundary layer until the mass transfer equilibrium coefficient falls into the preset range. Those skilled in the art can determine the corresponding equilibrium range based on the non-ferrous metal metallurgical engineering design specifications, combined with the specific electrolytic cell structure and production process.

[0131] The linear correspondence between the electric field regularity and the mass transfer equilibrium coefficient is based on the adaptation rules for electric field distribution and mass transfer state in the non-ferrous metallurgical engineering design code. Specifically, the linear correspondence is as follows:

[0132] ,in The proportionality coefficient, ranging from 0.5 to 2.0, is determined based on conventional process parameters such as the electrode spacing and current density of the electrolytic cell. The principle behind this linear correspondence is that the closer the mass transfer equilibrium coefficient is to 1, the more uniform the mass transfer state, and the lower the required electric field regularization intensity. Conversely, the greater the deviation of the mass transfer equilibrium coefficient from 1, the more severe the mass transfer unevenness problem, and the higher the required electric field regularization intensity. Through this linear correspondence, real-time adaptation of the electric field distribution to the boundary layer mass transfer state is achieved, avoiding the problem that a fixed intensity of electric field regularization cannot adapt to dynamically changing mass transfer states. This linear correspondence is based on the fundamental theories of electrochemical engineering, and those skilled in the art can determine the corresponding proportionality coefficient and linear relationship based on specific production process parameters.

[0133] The operation of homogenizing and regulating the electric field between electrodes is implemented using conventional techniques known in the art. These techniques include adjusting the parallelism of the electrodes, the distance between electrodes, the contact resistance of the conductive busbars, and adjusting the local current density through zoned power supply. These operations are conventional electric field regulation methods used in existing electrolytic copper refining production. Those skilled in the art can determine the corresponding regulation operation range based on the required electric field regulation intensity. For example, when the regulation intensity is high, the deviation range of the electrode distance can be reduced, the consistency requirement of the contact resistance of the conductive busbars can be improved, and the current distribution ratio of the zoned power supply can be adjusted.

[0134] Further explanation based on well-known electrochemical theories in this field reveals that the controlling factors of the electrocrystallization process include the mass transfer process and the charge transfer process. The mass transfer process corresponds to the mass transfer state of the boundary layer, while the charge transfer process corresponds to the electric field distribution between the electrodes. These two processes are mutually influential and mutually restrictive. Only when the mass transfer process and the charge transfer process are matched can stable and uniform electrocrystallization be achieved, resulting in high-purity cathode copper. In existing technologies, mass transfer regulation and electric field regulation are two independent processes with no linkage between them. This often leads to a mismatch between the mass transfer state and the electric field distribution, causing defects such as local current distortion, abnormal grain growth, and impurity co-deposition. This solution uses the mass transfer equilibrium coefficient as a linkage bridge between the two processes. Electric field normalization is only initiated after the mass transfer state is stable, while simultaneously ensuring that the intensity of the electric field normalization is matched with the mass transfer state in real time, thus achieving precise matching between the mass transfer process and the charge transfer process.

[0135] It should be noted that this solution integrates the previously independent mass transfer control and electric field control processes through a mass transfer equilibrium coefficient, thereby solving a series of purity problems caused by the mismatch between mass transfer and electric field in existing technologies.

[0136] Specifically, the determination of the mass transfer equilibrium coefficient range and the triggering of the electric field regularization operation form a synergy of pre-verification and subsequent execution. The electric field regularization operation will only be initiated when the mass transfer state reaches the preset requirement of stability and uniformity, ensuring that the effect of electric field regularization can be reflected in a stable mass transfer environment and avoiding interference from mass transfer fluctuations on the effect of electric field regularization. The linear correspondence between the mass transfer equilibrium coefficient and the electric field regularization intensity forms a synergy of quantitative input and precise output. The intensity of electric field regularization is dynamically adjusted according to the magnitude of the deviation of the mass transfer state from the uniform range, realizing real-time adaptation of electric field distribution and mass transfer state, avoiding the problems of over-regulation or under-regulation of fixed regularization intensity. The coordinated matching of mass transfer and electric field and the S5 electrocrystallization environment adjustment form a synergy of basic environment matching and crystallization process control. The precise matching of mass transfer and electric field provides a stable and uniform basic environment for cathode electrocrystallization, greatly improving the effect of subsequent electrocrystallization environment adjustment. The three support each other and realize the stable control of the entire chain from the basic environment to the crystallization process.

[0137] It should be noted that the speed of the electrocrystallization process in this scheme is determined by the slower of the mass transfer process and the charge transfer process. When the two are mismatched, local reaction runaway will occur. For example, when the mass transfer rate cannot keep up with the charge transfer rate, copper ion depletion will occur on the cathode surface, leading to defects such as hydrogen evolution, impurity co-deposition, and loose grains. This scheme uses the mass transfer balance coefficient as a linkage bridge to allow the electric field distribution and mass transfer state to be matched in real time, ensuring that the charge transfer rate and mass transfer rate at each point are matched, fundamentally avoiding the problem of abnormal local reaction.

[0138] This scheme clarifies that the electric field conditioning operation will only be initiated when the mass transfer equilibrium coefficient falls into the preset equilibrium range, ensuring that the electric field conditioning is always performed in a stable mass transfer environment. This not only guarantees the conditioning effect but also avoids the risk of superposition. This design completely changes the fixed operation mode of the existing technology that is performed periodically.

[0139] This solution achieves dynamic adaptive adjustment of the regularization intensity by establishing a linear correspondence between the electric field regularization intensity and the mass transfer equilibrium coefficient. When the mass transfer state deviates significantly from the uniform range, the regularization intensity is automatically increased; when the mass transfer state approaches the uniform range, the regularization intensity is automatically decreased. This ensures real-time adaptation between the electric field distribution and the mass transfer state while avoiding production fluctuations caused by over-regulation, making it highly practical for industrial applications.

[0140] As a preferred approach, step S6, which involves impurity co-deposition suppression intervention, is implemented according to the following steps:

[0141] (1) During the electrolysis operation, the impedance characteristics and integrity of the passivation film on the anode surface are detected online by in-situ AC impedance spectroscopy. The ion permeability coefficient of the microcracks in the anode passivation film is calculated by equivalent circuit fitting.

[0142] (2) By using a high-frequency and high-speed data acquisition system, the instantaneous fluctuation data of the inter-electrode potential is monitored in real time at a microsecond sampling interval, and the instantaneous potential shift coefficient caused by the oxygen evolution side reaction is separated and extracted.

[0143] (3) The real-time concentration of each controlled impurity in the electrolyte, the equilibrium precipitation potential of the corresponding impurity ions, the interfacial adsorption coefficient, and the real-time charge surface density data of the cathode interface are collected simultaneously. All parameters are substituted into the multi-impurity synergistic repulsion quantification model that couples the permeability of the anode microcrack and the instantaneous potential shift to calculate the comprehensive impurity repulsion coefficient at the corresponding time. The model calculation adopts the weighted summation and nonlinear fitting algorithm known in the field.

[0144] (4) Compare the calculated comprehensive impurity repulsion coefficient with the preset control threshold, and dynamically adjust the cathode interface charge density and the voltage regulation accuracy of the inter-electrode power supply according to the deviation amplitude to mitigate the risk of co-deposition caused by instantaneous potential shift. The adjustment command and the model calculation results are synchronized in real time to ensure that the instantaneous potential shift disturbance is mitigated within 100 microseconds.

[0145] (5) During the entire electrolysis cycle, the above parameters are continuously collected, calculated and controlled in a closed loop to maintain the continuous suppression effect on impurity co-deposition throughout the process. The calculation results of the entire cycle are simultaneously pushed to the S5 electrocrystallization environment adjustment step and the S1 colloidal system charge state pretreatment step to achieve closed-loop coordination throughout the entire process.

[0146] The expression for the multi-impurity synergistic repulsion quantization model that couples anodic microcrack permeability with instantaneous potential shift is as follows:

[0147]

[0148] In the formula:

[0149] The overall impurity rejection coefficient is dimensionless, and the threshold is determined based on the purity control target of high-purity cathode copper.

[0150] The summation sign is given for controlled impurities from type 1 to type m.

[0151] The number represents the type of controlled impurity, which is a positive integer with values ​​of 1, 2, 3... respectively, corresponding to controlled impurities such as arsenic, antimony, and bismuth;

[0152] The total number of controlled impurities is determined based on the types of impurities that are explicitly controlled in the national standard GB / T467.

[0153] The weighting coefficient for the k-th impurity is dimensionless and is set according to the stringency of the limit for the corresponding impurity in GB / T467. The lower the limit for the impurity, the larger the weighting coefficient.

[0154] Let be the equilibrium deposition potential of the k-th impurity ion;

[0155] The equilibrium deposition potential of copper ions is taken from the internationally accepted standard electrochemical thermodynamic electrode potential data table.

[0156] It is the natural logarithm function;

[0157] is the interfacial adsorption coefficient of the k-th impurity ion on the cathode surface, dimensionless, and set according to the industry standard YS / T959 for interfacial behavior of metallurgical electrolytes.

[0158] The surface charge density at the cathode interface is determined according to industry standards for electric field control in electrolysis systems.

[0159] The value is the ion permeability coefficient of the microcracks in the anodic passivation film, which is determined based on the theory of metal anodic dissolution and the design specifications of the copper electrolysis industry.

[0160] The instantaneous potential shift coefficient for the oxygen evolution side reaction is determined based on the standard definition of electrocrystallization kinetics and on-site data.

[0161] The calculation result of the comprehensive impurity repulsion coefficient is simultaneously used as the control basis for adjusting the electrocrystallization environment at the S5 cathode interface.

[0162] It is necessary to further explain that the multi-impurity synergistic repulsion quantification model coupled with anodic microcrack permeability and instantaneous potential shift adopted in this scheme has a clear hierarchical architecture, consisting of a standard four-layer architecture. The first layer of the model is the multi-source data acquisition input layer, and the input parameters are divided into four categories. The first category is anodic state parameters, including the ion permeability coefficient of the anodic passivation film microcrack. The second category is potential fluctuation parameters, including the instantaneous potential shift coefficient of the oxygen evolution side reaction. The third category is impurity characteristic parameters, including the types and quantities of controlled impurities. Impurity type serial number The weighting coefficient of the kth impurity Equilibrium deposition potential Interfacial adsorption coefficient The fourth category is cathode interface parameters, including the copper ion equilibrium deposition potential. Cathode interface charge surface density All input parameters are physical quantities that can be directly obtained at the electrolytic copper production site using known equipment and testing methods. In-situ AC impedance spectroscopy is a well-known method for detecting film characteristics in the field of electrochemistry. By applying a small AC perturbation to the anode surface and detecting the corresponding impedance response, the impedance characteristics and integrity of the anode passivation film can be calculated through equivalent circuit fitting, thereby obtaining the ion permeability coefficient of the microcracks. This method is a conventional detection technique known to those skilled in the art. The ion permeability coefficient ranges from 0 to 1. When the passivation film is intact and crack-free, ion permeability is high. The coefficient is 0. When a large number of cracks appear in the passivation film, the ion permeability coefficient approaches 1. Its value is determined based on the metal anodic dissolution theory and the design specifications of the copper electrolysis industry. High-frequency, high-speed data acquisition systems are common equipment in the industrial control field. Microsecond-level sampling intervals can capture instantaneous potential fluctuations caused by the oxygen evolution reaction. Through digital filtering algorithms, the high-frequency fluctuation component caused by the oxygen evolution reaction can be separated from the overall potential signal, and the instantaneous potential offset coefficient can be calculated. This separation and calculation method is a common signal processing algorithm known in the field. The total number of controlled impurities... Based on the types of impurities explicitly controlled in the national standard GB / T467 "Cathode Copper", high-purity cathode copper requires control of 18 impurities, including arsenic, antimony, bismuth, iron, lead, and tin. The value is 18. Those skilled in the art can adjust the number and types of controlled impurities according to the actual purity requirements of production; the weighting coefficient of the kth impurity... Based on the stringency of the limits for impurities set in GB / T467, the lower the limit, the greater the impact on purity, and the larger the corresponding weighting coefficient. For example, the limit for arsenic in high-purity cathode copper is 0.0005%, with a corresponding weighting coefficient of 1.2, and the limit for iron is 0.001%, with a corresponding weighting coefficient of 1.0. The sum of the weighting coefficients equals the total number of controlled impurities. To ensure the comparability of the weighted summation results; the equilibrium deposition potentials of impurity ions and copper ions were all taken from the internationally recognized standard electrode potential data table of electrochemical thermodynamics, namely the standard electrode potential table in the well-known Land's Handbook of Chemistry. Those skilled in the art can directly look up the table to obtain the equilibrium deposition potential at the corresponding temperature and concentration; the interfacial adsorption coefficient of impurity ions... According to the industry standard YS / T959 on interfacial behavior of metallurgical electrolytes, the adsorption characteristics of different impurity ions on the surface of copper cathodes are clearly defined. The value ranges from 0.5 to 1.5, determined based on the adsorption characteristics of the impurities; the cathode interface charge surface density. Based on industry standards for electric field control in electrolysis systems, these parameters can be calculated using the relationship between cathode current density and potential, and are well-known conventional electrochemical parameters in this field.

[0163] The second layer of the model is a weight allocation layer. Based on the impurity limit requirements of GB / T467, it assigns corresponding weight coefficients to different impurities. The logic is clear and reproducible, without any custom or non-public rules. The input is the limit requirement for each impurity, and the output is the weight coefficient of the corresponding impurity. .

[0164] The third layer of the model is the computational layer. It employs summation, division, natural logarithm, and multiplication operations—all well-known basic algorithms in mathematics. The nonlinear fitting logic conforms to the well-known theory of interfacial adsorption thermodynamics. The computational hierarchy is clearly defined, and the correspondence between input and output is unique. All parameters from the input layer and the weight allocation layer are directly fed into the computational layer for calculation, outputting a unique comprehensive impurity repulsion coefficient. .

[0165] The fourth layer of the model is the closed-loop execution output layer. The comprehensive impurity repulsion coefficient output by the model directly corresponds to two execution actions. First, it dynamically adjusts the charge density at the cathode interface and the voltage regulation accuracy of the inter-electrode power supply to mitigate the risk of co-deposition caused by instantaneous potential shifts and achieve closed-loop suppression of impurity co-deposition. Second, it is synchronously pushed to the S5 electrocrystallization environment adjustment step and the S1 colloidal system charge state pretreatment step to achieve closed-loop synergy throughout the entire process. The algorithm features are deeply bound to the impurity control technology features of electrolytic refining. The model's output directly drives the process actions, solving the problem of abnormal co-deposition of impurities such as arsenic, antimony, and bismuth.

[0166] This solution clarifies that the detection of the anolyte passivation film state and the acquisition of instantaneous potential fluctuations are the prerequisites for model calculation. This is because microcracks in the anolyte passivation film can lead to the localized release of impurity ions, and instantaneous potential shifts can disrupt the deposition potential balance between impurities and copper. These two factors are triggering factors for abnormal impurity co-deposition. Only by monitoring these two parameters in real time can the risk of impurity co-deposition be predicted in advance. Simultaneous acquisition of multiple parameters ensures the time consistency of the model input data and avoids calculation errors caused by asynchronous acquisition times of different parameters. The model calculation results directly drive the control actions, and the adjustment commands are synchronized with the calculation results in real time, ensuring that the instantaneous potential shift is smoothed within 100 microseconds, avoiding impurity co-deposition caused by instantaneous fluctuations. Continuous acquisition, calculation, and control throughout the entire cycle achieve continuous impurity suppression throughout the electrolysis process. At the same time, the calculation results are synchronously pushed to other processes, realizing closed-loop collaboration throughout the entire process.

[0167] The co-deposition of harmful impurities such as arsenic, antimony, and bismuth with copper is not determined solely by the overall concentration of the impurities, but rather by a combination of factors including the sudden release of anodic impurities, instantaneous potential shifts, interfacial adsorption characteristics, and cathode charge density. In particular, the localized sudden release of impurities caused by microcracks in the anodic passivation film, and the microsecond-level instantaneous potential shifts caused by the oxygen evolution side reaction, are the triggering factors for abnormal co-deposition of impurities. Existing technologies ignore these two instantaneous and localized influencing factors and can only passively control the situation by reducing the overall concentration of impurities, which cannot cope with this sudden co-deposition risk. This solution uses a multi-impurity synergistic repulsion quantification model to couple and calculate all factors affecting impurity co-deposition, achieving real-time prediction and precise suppression of co-deposition risk.

[0168] It should be noted that this solution uses a multi-factor, multi-impurity synergistic repulsion quantification model to couple and calculate all parameters affecting co-deposition, such as anode state, potential fluctuation, impurity characteristics, and cathode interface state, and outputs a unique comprehensive impurity repulsion coefficient. This coefficient can be used to predict the risk level of impurity co-deposition in real time and quantitatively. The lower the coefficient, the higher the risk of co-deposition. This design completely solves the problem that existing technologies cannot predict the risk of co-deposition.

[0169] The transient potential shift caused by the oxygen evolution side reaction lasts only tens to hundreds of microseconds, but it can cause a momentary negative shift in the cathode potential, disrupting the potential balance between impurities and copper deposition. This allows impurity ions that would otherwise not be deposited to co-deposit with copper. This solution uses a high-frequency, high-speed data acquisition system to capture the transient potential shift and calculates the corresponding control parameters in real time using a model. The adjustment commands and calculation results are synchronized in real time, ensuring that the transient potential shift is smoothed out within 100 microseconds, thus avoiding abnormal co-deposition caused by transient fluctuations.

[0170] During electrolysis, a lead oxide passivation film forms on the anode surface. This film prevents impurities in the anode from entering the electrolyte. However, when microcracks appear in the passivation film, impurities such as arsenic, antimony, and bismuth in the anode can rapidly enter the electrolyte through these cracks, forming a localized high-concentration region of impurities near the anode, leading to impurity co-deposition. This scheme introduces the ion permeability coefficient of the anode passivation film microcracks into a multi-impurity synergistic repulsion quantification model. This coefficient characterizes the risk of impurity burst release. When the ion permeability coefficient increases, the charge density at the cathode interface automatically increases, strengthening the electrostatic repulsion of impurity ions and compensating for the co-deposition risk caused by impurity burst release. This scheme assigns corresponding weight coefficients to different impurities through weighted summation, coupling the effects of multiple impurities in the calculation. Simultaneously, by nonlinearly fitting the synergistic effects of impurity adsorption, potential shift, and anode burst release using a natural logarithmic function, it achieves precise suppression of multi-impurity synergistic co-deposition.

[0171] As a preferred embodiment, the uniformization and normalization of the inter-electrode electric field described in S3 includes uniformly calibrating the flatness and verticality of all anode plates in the same tank, uniformly normalizing the parallelism and inter-electrode spacing of the cathode plates, uniformly processing the overlapping surfaces of the conductive busbars to homogenize the contact resistance, and simultaneously monitoring the current distribution of a single electrode plate in zones to eliminate local current density distortion. The current distribution monitoring data is synchronously input into the multi-impurity cooperative repulsion quantization model in S6 as auxiliary correction parameters for model calculation.

[0172] Further explanation is needed regarding the consistency calibration of the flatness and verticality of the anode plates. The implementation standard is determined according to the design specifications for non-ferrous metallurgical engineering. Specifically, the flatness deviation of the anode plates is controlled within ≤2mm / m, meaning the flatness deviation per meter of length does not exceed 2 millimeters. The verticality deviation is controlled within ≤1‰, meaning the deviation between the suspension centerline and the plumb line of the anode plate does not exceed one-thousandth. The calibration standards of all anode plates in the same tank are consistent to ensure that the working surfaces of all anode plates are in the same plane, avoiding electrode spacing deviation and electric field distortion caused by plate bending and suspension tilt. This calibration operation uses conventional methods known in the art, which can be completed using a spirit level, plumb line, and dial indicator. Those skilled in the art can complete the consistency calibration of the anode plates according to the above standards.

[0173] The parallelism of the cathode plates and the equidistant regularity of the electrode spacing are also implemented according to the design specifications for non-ferrous metallurgical engineering. Specifically, the parallelism deviation of the cathode plates is controlled within ≤1mm / m, and the electrode spacing deviation between the anode and cathode in the same cell is controlled within ±1mm. That is, the deviation of all electrode spacing values ​​from the set values ​​does not exceed ±1mm. The set value of the electrode spacing is determined according to the conventional electrolytic copper refining process, usually 90-110mm. Those skilled in the art can adjust the set value of the electrode spacing according to the specific current density and production process. The equidistant regularity operation can be completed using electrode spacing gauges and calipers known in the art, ensuring that all electrode spacings in the same cell are consistent and eliminating local current density distortion caused by uneven electrode spacing.

[0174] The purpose of uniform treatment of the busbar lap joint surfaces is to homogenize the contact resistance and avoid uneven current distribution on the plates caused by differences in contact resistance. The specific treatment method is a conventional method known in the art, including grinding and polishing the lap joint surfaces to remove oxide layers and oil stains, ensuring that the surface finish of the lap joint surfaces reaches Ra6.3 or less, and uniformly adjusting the torque of the fastening bolts on the lap joint surfaces. The torque value is determined according to the electrical design specifications for non-ferrous metallurgy, and is usually 25-35 N·m, ensuring that the contact resistance deviation of all lap joint surfaces is controlled within ≤5%. Those skilled in the art can complete the uniform treatment of the busbar lap joint surfaces according to the above standards.

[0175] The current distribution monitoring of a single electrode plate is implemented using conventional techniques known in the art. Specifically, multiple Hall current sensors are installed on the conductive rods of each electrode plate, dividing the plate into upper, middle, and lower sections along its height. The current density of each section is monitored separately, with the monitoring frequency consistent with the computation frequency of the S6 multi-impurity cooperative repulsion quantization model. This ensures that the monitoring data and model computation are synchronized. The monitored local current density data is synchronously input into the S6 multi-impurity cooperative repulsion quantization model as auxiliary correction parameters for model computation. Specifically, the deviation in local current density is corrected by adjusting the cathode interface charge surface density in the model using correction coefficients. The correction is made by adjusting the local current density. The higher the local current density, the larger the corresponding correction coefficient, to ensure that the model can accurately reflect the co-deposition risk caused by local current distortion. This correction method is based on the basic theory of electrochemistry. Those skilled in the art can determine the corresponding correction rules based on the correspondence between current density and charge surface density.

[0176] Uniform distribution of the electric field between electrodes is the foundation for achieving stable electrocrystallization. The flatness, perpendicularity, spacing consistency, and bus contact resistance of the electrodes are factors that affect the electric field distribution. Deviation of any of these factors will cause local current density distortion, leading to local precipitation potential shift, and in turn, defects such as impurity co-deposition, abnormal grain growth, and nodule formation. This scheme not only clarifies the specific implementation standards for electric field regularization, but also achieves real-time monitoring of the electric field distribution through zoned current monitoring. At the same time, it links the monitoring data with the impurity suppression model to achieve synergistic effects between electric field regularization and impurity control.

[0177] Specifically, the anode plate consistency calibration, cathode plate equidistant regularization, and busbar overlap surface treatment form a multi-dimensional synergistic regularization. This comprehensively regularizes the influencing factors of electric field distribution from three dimensions: plate installation accuracy, electrode spacing consistency, and conductive contact stability, rather than adjusting only one dimension as in existing technologies. These three aspects work together to ensure the initial uniformity of the electric field distribution from the source. The zonal monitoring of current distribution on a single plate and the elimination of local distortion form a real-time monitoring-dynamic correction synergy. Zonal monitoring allows for real-time monitoring of the dynamic changes in electric field distribution during electrolysis, timely detection and elimination of local current density distortion, achieving continuous stability of the electric field distribution throughout the entire electrolysis cycle. These two aspects support each other, solving the problem of existing technologies being unable to cope with dynamic electric field distortion. The current distribution monitoring data and the S6 multi-impurity synergistic repulsion quantization model form a synergistic electric field state-impurity control synergy. Local current distortion data is used as an auxiliary correction parameter for model calculation, allowing the suppression effect of impurity co-deposition to adapt to the dynamic changes in electric field distribution in real time, avoiding the risk of co-deposition caused by electric field distortion. These two aspects work together to achieve synergistic effects in electric field regularization and impurity control.

[0178] Example 2: Compared with Example 1, this example also includes the following technical features:

[0179] As a preferred option, the segmented dynamic adjustment of the cathode interface electrocrystallization environment in S5 is specifically as follows: according to the initial nucleation-dominant stage, the middle stable growth stage, and the later thickening and forming stage, corresponding interface impedance adjustment strategies are set respectively. By controlling the fluid disturbance intensity and charge transport state in the near-cathode region, the grain nucleation rate and growth rate are maintained in a preset matching relationship in each stage. The parameters of the adjustment strategy in each stage are taken from the real-time calculation results of the multi-impurity synergistic repulsion quantization model in S6.

[0180] Further explanation is needed. Specifically, the initial nucleation-dominant stage of electrolysis is the first 5%-10% of the electrolysis cycle, corresponding to a cathode deposition layer thickness ≤50μm. This stage aims to form uniform and dense crystal nuclei on the cathode substrate surface, laying the foundation for subsequent grain growth. The mid-electrolysis stable growth stage is 10%-90% of the electrolysis cycle, corresponding to a cathode deposition layer thickness of 50μm-2000μm. This stage is the main stage of cathode copper deposition, maintaining stable and uniform grain growth and avoiding abnormal grain growth and defects. The late-electrolysis thickening and shaping stage is the last 10% of the electrolysis cycle, corresponding to a cathode deposition layer thickness ≥2000μm. This stage aims to suppress the growth of nodules and dendrites on the deposition layer surface, ensuring the surface flatness and thickness uniformity of the cathode plate. This stage division is based on well-known copper electrocrystallization kinetics theory and industrial production practice. Those skilled in the art can determine the specific time points of each stage based on the specific electrolysis cycle length and deposition thickness requirements.

[0181] The interface impedance adjustment strategy for each stage is to change the electrochemical impedance characteristics of the cathode interface by regulating the fluid disturbance intensity and charge transport state in the near-cathode region, thereby controlling the nucleation and growth process of grains. The interface impedance includes Faraday impedance and diffusion impedance, which correspond to the charge transfer process and the mass transfer process, respectively. The implementation of this adjustment strategy is a conventional technique known in the art. Specifically, the fluid disturbance intensity in the near-cathode region is achieved by adjusting the opening degree of the electrolyte inlet branch and the deflection angle of the inlet distributor. The greater the disturbance intensity, the thinner the cathode boundary layer, the faster the mass transfer rate, and the smaller the diffusion impedance. The charge transport state is achieved by adjusting the waveform of the cathode current density and the voltage regulation accuracy of the inter-electrode potential. The more stable the waveform of the current density, the more stable the charge transfer process, and the more uniform the Faraday impedance. Based on the basic theory of electrochemical impedance, those skilled in the art can adjust the interface impedance through the above means.

[0182] The predetermined matching relationship between grain nucleation rate and growth rate is determined based on the well-known electrocrystallization theory in the art. Specifically, in the initial nucleation-dominant stage of electrolysis, it is necessary to increase the nucleation rate and decrease the growth rate, with the ratio of nucleation rate to growth rate controlled at ≥10, to ensure the formation of a large number of uniform and fine nuclei on the cathode surface and avoid the formation of coarse initial grains. In the stable growth stage of the middle stage of electrolysis, it is necessary to maintain a balance between the nucleation rate and growth rate, with the ratio controlled at 1-3, to ensure uniform and dense grain growth and avoid dendrites and loose structures. In the thickening and forming stage of the later stage of electrolysis, it is necessary to appropriately reduce the nucleation rate and maintain a stable growth rate, with the ratio controlled at 0.5-1, to ensure a smooth surface of the deposited layer and avoid the formation of nodules. Those skilled in the art can determine the corresponding ratio range based on the specific grain size requirements.

[0183] The combination of parameters of each stage adjustment strategy with the S6 multi-impurity synergistic repulsion quantization model is explained in this scheme. The parameters of each stage adjustment strategy, including fluid disturbance intensity, current density waveform, and potential regulation accuracy, are all taken from the real-time calculation results of the S6 model. Specifically, when the comprehensive impurity repulsion coefficient calculated by the S6 model is low, indicating a high risk of impurity co-deposition, the fluid disturbance intensity in the near-cathode region is increased to accelerate the interface mass transfer rate, avoid impurity enrichment at the interface, and simultaneously improve the regulation accuracy of the inter-electrode power supply to smooth out instantaneous potential shifts and suppress impurity co-deposition. When the comprehensive impurity repulsion coefficient is high, indicating a low risk of impurity co-deposition, the fluid disturbance intensity is reduced to maintain a stable charge transport state and ensure uniform grain growth. This parameter linkage logic is based on the basic theory of electrocrystallization and impurity co-deposition. Those skilled in the art can determine the corresponding parameter adjustment range based on the change in the comprehensive impurity repulsion coefficient.

[0184] The electrocrystallization process of copper consists of two steps: nucleation and growth. The matching relationship between the nucleation rate and the growth rate directly determines the grain size, density, smoothness, and purity of the deposited layer. When the nucleation rate is much greater than the growth rate, fine and dense grains are formed; when the growth rate is much greater than the nucleation rate, coarse and loose grains are formed, and even dendrites and nodules may appear. The structural defects of the grains provide a large number of adsorption sites for impurity ions, which greatly increases the risk of impurity co-deposition. This scheme sets corresponding interface impedance adjustment strategies in stages according to different stages of grain growth to maintain the optimal matching relationship between the nucleation rate and the growth rate. At the same time, the adjustment parameters are linked with the calculation results of the impurity suppression model to achieve synergistic effect of grain growth control and impurity suppression.

[0185] It should be noted that this scheme employs segmented, precise control based on the kinetics of electrocrystallization. Specifically, the division into three stages of electrolysis and the interfacial impedance adjustment strategies for each stage form a synergistic effect of stage division and precise adaptation. Corresponding adjustment strategies are set to meet the grain growth requirements of different stages. In the initial stage of electrolysis, the nucleation rate is increased by adjusting the interfacial impedance, forming a uniform and dense crystal substrate. In the middle stage, the balance between nucleation and growth is maintained by adjusting the interfacial impedance, achieving stable and uniform grain growth. In the later stage, the growth of dendrite nodules is suppressed by adjusting the interfacial impedance, ensuring the smoothness of the deposited layer. These three aspects work together to achieve precise control of grain growth throughout the entire electrolysis cycle.

[0186] The parameters of the adjustment strategy at each stage, together with the S6 multi-impurity synergistic repulsion quantification model, form a synergy between grain growth control and impurity co-deposition suppression. Based on the risk level of impurity co-deposition, the control parameters of the electrocrystallization environment are dynamically adjusted. While ensuring uniform grain growth, the co-deposition of impurities is suppressed simultaneously, avoiding the vicious cycle of grain defects and impurity adsorption. The two work together to achieve a simultaneous improvement in grain density and cathode plate purity.

[0187] It should be noted that the controlling factors in the electrocrystallization process of copper differ at different electrolysis stages. In the initial stage of electrolysis, nucleation is crucial, requiring a high nucleation rate to form a uniform crystal substrate. In the middle stage, stable growth is essential, requiring a balance between nucleation and growth rates to ensure the compactness of the deposited layer. In the later stage, surface smoothness is paramount, necessitating the suppression of abnormal grain growth to prevent nodule dendrite formation. However, existing technologies use fixed process parameters, which can only meet the growth requirements of a specific stage and cannot achieve precise adaptation throughout the entire cycle. This solution divides the electrolysis cycle into three stages according to the kinetics of electrocrystallization. For each stage, a corresponding interface impedance adjustment strategy is set to precisely control the matching relationship between nucleation and growth rates, achieving precise control of grain growth throughout the entire electrolysis cycle.

[0188] This scheme links the parameters of the electrocrystallization adjustment strategy with the real-time calculation results of the S6 multi-impurity synergistic repulsion quantization model. When the risk of impurity co-deposition is high, the electrocrystallization environment is adjusted synchronously. On the one hand, the fluid disturbance intensity is increased to avoid impurity enrichment at the interface. On the other hand, the charge transport state is stabilized to suppress impurity co-deposition. At the same time, the uniform growth of the grains is maintained, the defect sites are reduced, and the vicious cycle of grain defects and impurity adsorption is broken, thus achieving the simultaneous improvement of grain compactness and cathode purity.

[0189] As a preferred embodiment, the surface cleanliness maintenance treatment described in S7 specifically includes:

[0190] Low-tension, low-flow-rate directional spraying is used to remove the electrolyte adhering to the cathode surface, followed by dry purging with inert gas to remove residual droplets and adsorbed colloidal impurities. The spraying pressure and purging airflow velocity are adaptively adjusted based on the monitoring results of colloidal impurity concentration downstream of the filter-type interception structure.

[0191] After the cleaning process is completed, the amount of residual impurities on the surface of the cathode plate is detected online. The detection results are simultaneously fed back to the process control steps of the entire process for optimization of process parameters in subsequent batches.

[0192] Further explanation is needed regarding the purpose of low-tension, low-flow-rate directional spraying. This aims to remove surface-adhered electrolyte without damaging the cathode plate deposition layer, preventing residual contamination from impurities in the electrolyte after surface drying. The spraying fluid uses a well-known low-tension clean electrolyte, specifically a deeply purified copper sulfate-sulfuric acid solution with the same composition as the electrolysis system. This avoids introducing new impurities into the cathode plate. The surface tension of the spraying fluid is controlled to ≤40 mN / m, achieved by adding trace amounts of a commonly used surfactant in electrolysis systems. This surfactant does not contaminate the cathode plate and is easily removed by subsequent purging processes. The spray flow rate is controlled at 0.5-1.5 m / s, and the spray pressure is controlled at 0.05-0.15 MPa. This parameter range is within the low flow rate and low pressure range, which can effectively remove the electrolyte adhering to the surface without causing mechanical erosion damage to the deposition layer on the cathode plate surface, avoiding defects such as grain shedding and surface scratches. The spraying method is directional spraying, with the spraying direction at an angle of 30°-45° to the cathode plate surface, ensuring that the spray liquid can cover the entire cathode plate surface, while avoiding direct impact of the spray liquid on the deposition layer. Those skilled in the art can select an existing spraying system based on the above parameter range and the size specifications of the cathode plate.

[0193] The purpose of dry purging with inert gas is to remove residual spray liquid droplets and adsorbed colloidal impurities from the surface of the cathode plate, preventing water stains and impurities from forming on the surface after the residual liquid dries. The inert gas used is nitrogen, argon, or other inert gases that do not react with copper, and the gas purity is controlled at ≥99.99% to avoid secondary contamination of the cathode plate by impurities in the gas. The purging airflow velocity is controlled at 5-15 m / s, and the purging direction is parallel to the cathode plate surface. Laminar flow purging removes droplets and adsorbed impurities from the surface, avoiding droplet splashing and secondary contamination caused by vertical purging. The purging time is controlled at 30-60 seconds to ensure that the entire cathode plate surface is dry and free of residual droplets.

[0194] The adaptive adjustment rules for spray pressure and purging airflow velocity in this scheme are based on the monitoring results of colloidal impurity concentration downstream of the existing filter-type interception structure. Specifically, when the detected colloidal impurity concentration is high, it indicates that there are more residual colloidal impurities in the electrolyte, and the colloidal impurities adsorbed on the cathode plate surface will also increase accordingly. Therefore, the spray pressure and purging airflow velocity should be increased to enhance the cleaning effect. When the detected colloidal impurity concentration is low, it indicates that the content of colloidal impurities in the electrolyte is low. Therefore, the spray pressure and purging airflow velocity should be reduced accordingly to ensure the cleaning effect while avoiding energy waste and mechanical damage to the cathode plate surface. The adaptive adjustment relationship is linear, with a proportionality coefficient of 0.01 MPa / (mg / L) for spray pressure and 1 m / s / (mg / L) for purging airflow velocity. These proportionality coefficients are determined according to the cathode plate cleaning specifications of the non-ferrous metallurgical industry. Those skilled in the art can determine the corresponding spray pressure and purging airflow velocity based on the monitoring results of the colloidal impurity concentration.

[0195] The online detection of residual impurities on the cathode plate surface is performed using laser-induced breakdown spectroscopy (LIBS), a method well-known in the art. This method enables rapid, non-destructive, and online detection of impurity content on the cathode plate surface, covering all controlled impurities specified in GB / T467. The detection time is controlled within 1 minute, adapting to the operational rhythm of production lines. The detection results include the residual amount of each impurity on the surface and the overall cleanliness level. Those skilled in the art can complete the deployment and operation of the online detection system based on the well-known LIBS detection method.

[0196] The feedback optimization logic of the test results clarifies that the test results are synchronously fed back to the entire process control steps for the optimization of process parameters in subsequent batches. Specifically, when the residual amount of impurities on the cathode plate surface is found to exceed the standard, the control intensity of the S1 colloidal system charge state pretreatment, the interception intensity of the S4 in-situ interface barrier treatment, and the intensity of the S6 impurity co-deposition inhibition intervention in subsequent batches are increased to reduce the impurity content in the electrolyte from the source and reduce impurity adsorption on the cathode plate surface. When mechanical damage is detected on the cathode plate surface, the spray pressure and purging airflow velocity of the cleaning treatment in subsequent batches are reduced to avoid damage to the deposition layer. This feedback optimization logic forms a complete closed loop throughout the entire process, realizing continuous optimization of process parameters. Based on the test results, those skilled in the art can determine the corresponding parameter optimization direction.

[0197] When the cathode plate is removed from the electrolytic cell, a layer of electrolyte adheres to its surface. The electrolyte contains copper ions, sulfuric acid, and residual impurity ions and colloidal particles such as arsenic, antimony, and bismuth. When the electrolyte dries, these impurities remain on the cathode plate surface, causing surface contamination and even penetrating into the grain boundaries of the deposited layer, affecting the overall purity of the cathode plate. In existing technologies, the cleaning of cathode plates is usually done by rinsing with water and air drying. This not only fails to completely remove adsorbed colloidal impurities but also leads to problems such as water stains and oxidation discoloration on the surface. Furthermore, it does not link the cleaning process parameters with the impurity interception effect at the front end, nor does it achieve closed-loop optimization of the process through detection results. This solution achieves non-destructive cleaning of the cathode plate surface through the synergistic effect of low-tension directional spraying and dry purging with inert gas. At the same time, through parameter adaptive adjustment and result feedback optimization, it achieves synergistic linkage between the cleaning process and the entire process flow.

[0198] It should be noted that this solution achieves non-destructive deep cleaning of the cathode plate surface, thoroughly removing adsorbed colloidal impurities while avoiding surface oxidation and mechanical damage. The cathode plate deposition layer has numerous grain boundaries and microscopic defects, where colloidal impurities are firmly adsorbed. This solution uses a low-tension clean electrolyte as the spraying liquid, whose composition is consistent with the electrolyte system, preventing oxidation of the copper surface. The low-tension characteristic also better wets the grain boundaries and microscopic defects, desorbing the adsorbed colloidal impurities. Then, a parallel inert gas laminar flow is used to thoroughly remove the desorbed impurities and residual droplets. The entire process uses low-pressure, low-flow-rate parameters, causing no mechanical damage to the deposition layer, thus achieving non-destructive deep cleaning.

[0199] In addition, the concentration of residual colloidal impurities in the electrolyte fluctuates dynamically with changes in electrolysis batch, anode composition, and process parameters. When the concentration of colloidal impurities is high, more impurities will be adsorbed on the cathode plate surface, requiring a stronger cleaning intensity. This solution links the spray pressure and purging airflow velocity of the cleaning process with the colloidal impurity concentration monitoring results downstream of the front-end filter-type interception structure. Based on the dynamic changes in impurity concentration, the cleaning parameters are adaptively adjusted. When the impurity concentration is high, the cleaning intensity is automatically increased to ensure the cleaning effect. When the impurity concentration is low, the cleaning intensity is automatically reduced to avoid waste, achieving a precise match between cleaning intensity and contamination level.

[0200] This solution involves online detection of residual impurities on the surface of the cleaned cathode plate, and synchronous feedback of the detection results to the entire process control steps. Problems discovered during the detection are used to optimize the front-end process parameters of subsequent batches. For example, when the residual arsenic and antimony impurities on the surface exceed the standard, the impurity co-deposition inhibition strength of S6 and the colloidal interception strength of S4 are increased to reduce the impurity content from the source. When mechanical damage occurs on the surface, the spray pressure and purging speed of the cleaned treatment are reduced to prevent the damage from recurring, thus achieving continuous optimization and improvement of the entire process chain.

[0201] As a preferred approach, throughout the entire process from steps S1 to S7, the colloidal electrokinetic potential of the electrolyte, the thickness of the cathode diffusion boundary layer, and the regularity of the inter-electrode electric field are monitored online simultaneously. The mass transfer equilibrium coefficient calculated by the mass transfer equilibrium quantification model and the comprehensive impurity repulsion coefficient calculated by the multi-impurity synergistic repulsion quantification model are used together as feedback variables. The monitoring data and the calculated data are simultaneously input into the process control link to form a multi-parameter closed-loop synergistic control system.

[0202] Further explanation is needed. Specifically, the colloidal electrokinetic potential of the electrolyte corresponds to the charge state pretreatment step of the colloidal system in S1, and is a parameter controlling the electrophoretic migration of colloidal impurities. Its monitoring method is an online zeta potential analyzer known in the art, with a monitoring frequency of 1 time / minute. The cathode diffusion boundary layer thickness corresponds to the boundary layer mass transfer environment construction step in S2, and is a parameter controlling the interface mass transfer state. Its monitoring method is the online electrochemical impedance method known in the art, with a monitoring frequency of 1 time / 2 hours, consistent with the model calculation frequency in claim 4. The inter-electrode electric field regularity corresponds to the inter-electrode electric field homogenization step in S3, and is a parameter controlling the uniformity of electric field distribution and current density. Its calculation method is the relative standard deviation of the current density of a single electrode zone. The smaller the deviation, the higher the regularity. The monitoring frequency is 1 time / 10 minutes. The three parameters correspond to the three dimensions of colloidal impurity control, interface mass transfer control, and electric field distribution control, respectively, covering all aspects affecting the purity of the cathode plate. Based on the above description, those skilled in the art can complete the layout and parameter setting of the monitoring system.

[0203] The two feedback variables, namely the mass transfer equilibrium coefficient and the comprehensive impurity repulsion coefficient, are used as feedback variables because they are the coupled quantitative results of multiple parameters in the entire process. The mass transfer equilibrium coefficient comprehensively reflects the mass transfer state of the cathode interface, the near-wall flow state, and the physicochemical properties of the electrolyte. The comprehensive impurity repulsion coefficient comprehensively reflects the anode state, potential fluctuations, impurity characteristics, cathode interface state, and co-deposition risk. The two coefficients together determine the stability and purity of the cathode electrocrystallization process and are quantitative indicators of the entire process scheme. The calculation frequencies of the two coefficients are 1 time / 2 hours and 1 time / 100 microseconds, respectively, to adapt to the slow-changing mass transfer process and the fast-changing potential fluctuation process, ensuring the timeliness and accuracy of control.

[0204] The architecture of the multi-parameter closed-loop collaborative control system is divided into a three-layer standard architecture. Specifically, the first layer is the data acquisition and input layer. The input data is divided into two categories: one is three real-time monitoring parameters obtained synchronously online, namely the electrolyte colloidal electromotive potential, cathode diffusion boundary layer thickness, and inter-electrode electric field regularity; the other is the mass transfer equilibrium coefficient and comprehensive impurity repulsion coefficient calculated by two models. All input data are acquired synchronously in real time with corresponding timestamps, avoiding control errors caused by data asynchrony. The second layer is the control calculation layer, which adopts the well-known PID closed-loop control logic, namely proportional-integral-derivative control logic. This is the most commonly used closed-loop control algorithm in the field of industrial process control, without any custom non-known control logic. The calculation layer combines the input monitoring data and feedback variables with the corresponding preset... Thresholds are compared to calculate the deviation value, and then the corresponding process control command is output through the PID control algorithm to ensure that all parameters are always maintained within the preset reasonable range. The third layer of the system is the execution output layer, and the output control commands correspond to all processes from S1 to S7, including the adjustment of charge regulator dosage in S1, the adjustment of inlet branch pipe opening and distributor angle in S2, the adjustment of electrode plate and busbar alignment in S3, the adjustment of backwash frequency and interception intensity in S4, the adjustment of interface impedance adjustment strategy in S5, the adjustment of cathode charge density and power supply voltage regulation accuracy in S6, and the adjustment of spray pressure and purging speed in S7. This realizes the coordinated closed-loop control of all processes. The hierarchy of the entire system is clear and the input-output relationship is clear. Based on the above description, those skilled in the art can build this control system in the DCS system of the existing electrolysis production line.

[0205] The specific implementation of the PID closed-loop control logic, including the tuning of its proportional coefficient, integral coefficient, and derivative coefficient, is determined according to the general design specifications of the non-ferrous metals metallurgy industry. At the same time, the critical proportional coefficient method, which is well-known in the field, is used for on-site tuning to ensure the stability and speed of the control process, without overshoot or oscillation, and to adapt to the characteristics of the electrolytic copper refining production process. Those skilled in the art can complete the tuning of the PID parameters based on common knowledge of industrial process control.

[0206] The multi-parameter closed-loop collaborative control system constructed in this scheme incorporates all parameters affecting the purity of the cathode plate into the same control system, takes into account the coupling relationship between parameters, and uses two coupling quantization coefficients as feedback variables to achieve collaborative control of all processes, avoid mutual interference between parameters, and ensure the stability of the entire production process.

[0207] It should be noted that this scheme uses two models with different sampling frequencies and different calculation cycles to correspond to the slow-changing mass transfer process and the fast-changing impurity co-deposition process, respectively. The calculation cycle of the mass transfer equilibrium coefficient is 2 hours, which is adapted to the slow-changing mass transfer process and ensures the stability of the control. The calculation cycle of the comprehensive impurity repulsion coefficient is 100 microseconds, which is adapted to the fast-changing instantaneous potential fluctuations and ensures the timeliness of the control. At the same time, the two coefficients are used as feedback variables and incorporated into the same control system, realizing the coordinated control of the slow-changing process and the fast-changing process. This not only ensures the stability of the entire production process, but also enables rapid response to sudden instantaneous risks.

[0208] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention. For those skilled in the art, any alternative improvements or transformations made to the implementation of the present invention fall within the protection scope of the present invention.

[0209] Any aspects of this invention not described in detail are well-known to those skilled in the art.

Claims

1. A method for improving the purity of cathode plates by controlling the electrolytic copper refining process, characterized in that, Includes the following steps: S1. Pre-treat the colloidal system charge state of the circulating electrolyte and achieve steady-state dispersion of inorganic hydroxyl colloids and organic degradation colloids in the electrolyte through interfacial charge compensation. S2. After pretreatment, during the electrolysis start-up stage, a uniform mass transfer environment of diffusion boundary layer is constructed on the cathode surface to correct the Reynolds number distribution of fluid in the near-wall region of the cathode and unify the material transfer conditions at the interface between the main electrolyte and the cathode. S3. After starting the electrolytic deposition process, the electric field between the electrodes is homogenized and regulated to compensate for the ion flux deviation caused by microcracks in the anode passivation film and to suppress local current distortion and deposition potential shift between the electrodes. S4. During the electrolytic deposition process, in-situ interface barrier treatment is simultaneously implemented in the electrolyte circulation path to target and adsorb colloidal impurity particles in the electrolyte. S5. After completing the inter-electrode electric field regulation in step S3, dynamically adjust the cathode interface electrocrystallization environment in stages according to the electrolysis process to suppress the instantaneous potential shift disturbance of the oxygen evolution side reaction and maintain the homogeneous nucleation and growth conditions of the deposited grains. S6. During the entire electrolysis cycle, based on the electrocrystallization environment parameters fed back from step S5 and the difference in deposition potential between impurities and copper, continuous intervention to suppress impurity co-deposition is implemented to enhance the selective reduction deposition of copper ions. The data on the impurity suppression effect is synchronously transmitted back to the preprocessing module of step S1 to form a closed loop of full-process collaboration. S7. After electrolysis, based on the barrier effect monitoring data fed back from step S4, the cathode plate is subjected to surface cleaning and maintenance treatment to remove interface adsorbed impurities and residual electrolyte, thereby obtaining a high-purity cathode copper plate.

2. The process method according to claim 1, characterized in that, The pretreatment of the charge state of the colloidal system in step S1 is as follows: (1) Online detection of colloidal electrokinetic potential, ionic strength, relative content of organic degradation products and concentration of trace fluoride ions in circulating electrolyte, and comprehensive determination of the instability risk level of colloidal system; (2) Based on the level of instability risk, charge regulators are added directionally to the electrolyte buffer tank to unify the surface charge state of colloidal particles to the preset negative charge range. (3) Low-shear homogeneous disturbance is applied to the electrolyte in the buffer tank to eliminate local charge accumulation and colloidal agglomerates; (4) Static homogenize the disturbed electrolyte and send it into the electrolytic cell system after the colloidal electric potential stabilizes; wherein, the static homogenization completion signal serves as the only pre-trigger condition for the start of electrolysis in step S2.

3. The process method according to claim 1, characterized in that, The in-situ interface barrier treatment in step S4 is as follows: (1) At the front end of the liquid distributor of the electrolytic cell, colloidal impurities that are oppositely charged to the cathode surface are pre-adsorbed and retained; (2) A filter-type interception structure is arranged in the inter-electrode barrier between the cathode and the anode to intercept micro- and nano-sized colloidal impurities step by step according to the particle size scale. (3) Periodically perform micro-flow backwashing on the interception section of the filter-type interception structure; (4) The impurity enrichment solution discharged from backwashing is introduced into an independent purification branch and is not returned to the main electrolyte circulation system; (5) A particle concentration monitoring node is set downstream of the filter-type interception structure to monitor the penetration rate of colloidal impurities in real time. When the penetration rate exceeds the preset limit, the backwashing frequency and interception intensity are automatically adjusted. The penetration rate monitoring data in step (5) is used as the input parameters for the spray pressure and purging speed of the surface cleanliness maintenance treatment in step S7.

4. The process method according to claim 1, characterized in that, S2 constructs a uniform mass transfer environment for the cathode diffusion boundary layer, and is carried out according to the following steps: (1) Before electrolysis is started, the fluid velocity in the near-wall region of the cathode working surface is calibrated point by point to obtain basic data on the near-wall Reynolds number distribution at different points on the entire cathode plate. (2) After electrolysis is started, the concentration of trace fluoride ions, free hydrogen ions and copper ions in the main electrolyte are collected online and the real-time characteristic thickness of the cathode diffusion boundary layer is detected simultaneously. (3) Substitute all the detection data collected in the above steps into the mass transfer equilibrium quantization model with near-wall Reynolds number correction, and calculate the mass transfer equilibrium coefficient at the corresponding time. (4) Compare the calculated mass transfer equilibrium coefficient with the preset high-purity production equilibrium range, adjust the opening of the electrolyte inlet branch and the deflection angle of the inlet distributor according to the deviation range, correct the Reynolds number distribution in the cathode near-wall region, until the mass transfer equilibrium coefficient stably falls into the preset range. (5) During the entire electrolysis process, the above detection, calculation and adjustment steps are repeated every 2 hours to dynamically maintain the stability of the mass transfer state of the cathode boundary layer throughout the process. The calculation results of each round are simultaneously pushed to the S3 inter-electrode electric field homogenization and S5 electrocrystallization environment adjustment steps. The expression for the mass transfer equilibrium quantization model coupled with near-wall Reynolds number correction is:

5. In the formula: This is the mass transfer equilibrium coefficient; The symbol for the closed surface integral along the effective deposition area of ​​the cathode; The modulus of the copper ion concentration gradient in the electrolyte; The characteristic thickness of the cathode diffusion boundary layer; This is the Reynolds number correction factor for the near-wall region of the cathode; The area of ​​a micro-element of the cathode working surface; is the diffusion coefficient of copper ions in the electrolyte; It is a natural exponential function; This is a correction factor for the effect of acidity. This refers to the concentration of trace fluoride ions in the electrolyte. The concentration of free hydrogen ions in the main electrolyte; This represents the total effective deposition area of ​​the cathode.

6. The process method according to claim 4, characterized in that, When the mass transfer equilibrium coefficient falls into the preset equilibrium range, the interelectrode electric field homogenization and normalization operation of S3 is initiated, and the mass transfer equilibrium coefficient is used as the input variable of the electric field normalization intensity, so that the electric field distribution and the boundary layer mass transfer state are adapted in real time, and the electric field normalization intensity and the mass transfer equilibrium coefficient have a linear correspondence.

7. The process method according to claim 1, characterized in that, Step S6, which involves impurity co-deposition suppression intervention, is implemented according to the following steps: (1) During the electrolysis operation, the impedance characteristics and integrity of the passivation film on the anode surface are detected online, and the ion permeability coefficient of the microcracks in the anode passivation film is calculated by equivalent circuit fitting. (2) By using a high-frequency and high-speed data acquisition system, the instantaneous fluctuation data of the inter-electrode potential is monitored in real time at a microsecond sampling interval, and the instantaneous potential shift coefficient caused by the oxygen evolution side reaction is separated and extracted. (3) The real-time concentration of each controlled impurity in the electrolyte, the equilibrium precipitation potential of the corresponding impurity ions, the interfacial adsorption coefficient, and the real-time charge surface density data of the cathode interface are collected simultaneously. All parameters are substituted into the multi-impurity synergistic repulsion quantification model that couples the permeability of the anode microcrack and the instantaneous potential shift to calculate the comprehensive impurity repulsion coefficient at the corresponding time. (4) Compare the calculated comprehensive impurity repulsion coefficient with the preset control threshold, and dynamically adjust the cathode interface charge density and the voltage regulation accuracy of the inter-electrode power supply according to the deviation amplitude to mitigate the risk of co-deposition caused by instantaneous potential shift. The adjustment command and the model calculation results are synchronized in real time to ensure that the instantaneous potential shift disturbance is mitigated within 100 microseconds. (5) During the entire electrolysis cycle, the above parameters are continuously collected, calculated and controlled in a closed loop to maintain the continuous suppression effect on impurity co-deposition throughout the process. The calculation results of the entire cycle are simultaneously pushed to the S5 electrocrystallization environment adjustment step and the S1 colloidal system charge state pretreatment step to achieve closed-loop coordination throughout the entire process.

8. The process method according to claim 1, characterized in that, The inter-electrode electric field homogenization and regularization described in S3 includes uniform calibration of the flatness and verticality of all anode plates in the same tank, equidistant regularization of the parallelism and inter-electrode spacing of the cathode plates, uniform treatment of the overlapping surfaces of the conductive busbars to homogenize the contact resistance, and zoned monitoring of the current distribution of a single electrode plate to eliminate local current density distortion. The current distribution monitoring data is synchronously input into the multi-impurity cooperative repulsion quantization model in S6 as auxiliary correction parameters for model calculation.

9. The process method according to claim 1, characterized in that, The segmented dynamic adjustment of the cathode interface electrocrystallization environment in S5 is as follows: according to the initial nucleation-dominant stage, the middle stable growth stage, and the later thickening and forming stage, corresponding interface impedance adjustment strategies are set respectively. By controlling the fluid disturbance intensity and charge transport state in the near-cathode region, the grain nucleation rate and growth rate are maintained in a preset matching relationship in each stage. The parameters of the adjustment strategy in each stage are taken from the real-time calculation results of the multi-impurity synergistic repulsion quantization model in S6.

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