Zinc electrodeposition anode slime recovery treatment method

Abstract

The invention relates to a zinc electrodeposition anode slime recovery treatment method, and belongs to the technical field of zinc hydrometallurgy. The cleaned anode slime is discharged into a spiral classifier to be subjected to classified filtration, grinding is conducted twice through a ball mill, and a filter press is adopted for conducting anode slime filter pressing enrichment treatment on the ground anode slime; according to the method, the anode slime is ground twice, the anode slime filter pressing residues obtained after filter pressing and enrichment are returned to a liquid preparation plant, and the anode slime filter pressing residues serve as oxidizing agents to replace manganese powder to be put into an acid leaching tank to enter the leaching process at all manganese powder use points in the zinc leaching procedure, so that the consumption of the manganese powder in the zinc leaching procedure is effectively reduced; the leaching rate of manganese is high, the utilization rate of manganese ions is effectively improved, the recycling process is simple, the production cost is low, and the problems that hydrogen peroxide is used in a traditional recycling method to harm human bodies and the electrolysis cost is high when an electrolysis mode is adopted are solved.

Description

Technical Field

[0001] The invention relates to a method for recovering and treating zinc electrodeposition anode mud, belonging to the technical field of hydrometallurgy of zinc. Background Art

[0002] In the hydrometallurgical zinc smelting process, zinc electrowinning usually uses Pb-Ag alloy anodes. After direct current is passed, the Pb on the anode first generates PbSO4 or PbO2, and the manganese ions in the electrolytic solution exist in the form of divalent ions. In the anode process, an oxidation reaction occurs to generate MnO2. A part of MnO2 is adsorbed on the surface of the anode plate and forms a dense anode protective film together with the PbO2 on the anode surface. This protective film can reduce the lead content in the cathode zinc and improve the quality of the cathode zinc. The other part of MnO2 is precipitated at the bottom of the electrolytic cell to form anode mud. In the zinc electrowinning process, the manganese ions in the electrolytic solution exist in the form of divalent ions. In the anode process, an oxidation reaction occurs to generate MnO2. A part of MnO2 is adsorbed on the surface of the anode plate and forms a dense anode protective film together with the PbO2 on the anode surface. This protective film can reduce the lead content in the cathode zinc and improve the quality of the cathode zinc. The other part of MnO2 is precipitated at the bottom of the electrolytic cell to form anode mud. Depletion will cause anode corrosion and seriously affect the quality of cathode zinc. However, if the manganese ion concentration is too high, it will increase the resistance of the solution, resulting in an increase in the cell voltage and increased power consumption. Therefore, controlling the stability of the manganese ion content in the electrolytic solution is of great significance to zinc electrolytic production. Usually, the manganese ion content in the electrolytic solution is 3-5g / L. In order to maintain a stable manganese ion content, the current main method of manganese supplementation is to use manganese powder to react with dilute sulfuric acid in the leaching process to prepare a high manganese solution to supplement the process. However, due to the generation of anode mud, the zinc electrolytic process has problems such as low manganese ion utilization, large manganese powder input and high production cost.

[0003] In order to prevent anode mud from being deposited in large quantities at the bottom of the tank, causing the cathode and anode to contact in the tank and thus causing a short circuit between the two poles, it is necessary to clean the anode mud in the electrolytic cell regularly. For the cleaned anode mud, in order to recover the manganese, lead and silver in the anode mud, there are currently some anode mud recovery and treatment methods, such as the method for direct leaching of manganese dioxide from electrolytic zinc anode mud disclosed in Chinese patent publication number CN102168177B, which first ball-mills the anode mud, and then uses hydrogen peroxide as a reducing agent to reduce and leach the manganese dioxide in the anode mud in an acidic system to achieve the recovery of manganese. However, this method has the problems of large amount of hydrogen peroxide used and high production cost, and the problem that hydrogen peroxide is highly volatile and corrosive and harmful to the human body; and a method for recovering zinc, manganese, lead and silver from zinc electrolytic anode mud disclosed in Chinese patent publication number CN102912138B, in which the anode mud is wet-milled and then filtered, the filtrate is used as the raw material of the zinc smelting system, the filter residue is mixed with an acidic solution to leach manganese, and then manganese dioxide is prepared from the purified leachate by electrolysis, but this method has the problems of complex recovery process, low utilization rate of manganese ions and high electrolysis cost. Summary of the invention

[0004] In order to overcome the problems existing in the background technology, the present invention proposes a method for recovering and treating zinc electrolytic anode mud, in which the anode mud filter press residue is returned to a liquid preparation plant after grinding the anode mud twice and filtering and enriching the anode mud, and the anode mud filter press residue is used as an oxidant instead of manganese powder at each manganese powder use point in the zinc leaching process and put into an acid leaching tank to enter the leaching process, thereby effectively reducing the manganese powder consumption in the zinc leaching process, achieving a high manganese leaching rate, effectively improving the utilization rate of manganese ions, having a simple recovery and treatment process and a low production cost, thereby avoiding the problem of the traditional recovery method using hydrogen peroxide that is harmful to the human body and the problem of the high cost of electrolysis using the electrolysis method.

[0005] To solve the above problems, the present invention is implemented through the following technical solutions:

[0006] A method for recovering zinc electrowinning anode mud comprises at least the following steps:

[0007] S1: The anode plate with anode mud is placed in an anode cleaning and leveling machine for leveling and cleaning with high-pressure water. The cleaned anode plate is transported for standby use;

[0008] S2: the anode mud slurry formed after cleaning in step S1 is discharged into a spiral classifier for classification and filtration to separate the anode mud slurry and anode washing water;

[0009] S3: the anode mud slurry separated in step S2 is discharged into a ball mill for primary grinding, and the anode washing water is discharged into an anode washing water tank for storage;

[0010] S4: The anode mud in the electrolytic cell is discharged into the vacuum liquid receiving tank for collection and storage, and then introduced into the anode mud overflow tank;

[0011] S5: the anode mud discharged from the ball mill in step S3 and the anode mud discharged from the anode mud overflow tank in step S4 are uniformly introduced into the anode mud intermediate barrel for storage;

[0012] S6: the anode washing water in the anode washing tank in step S3 and the anode mud in the anode mud intermediate barrel in step S5 are simultaneously discharged into a spiral classifier for classification and filtration to separate the anode mud and the supernatant;

[0013] S7: discharging the anode mud separated in step S6 into a ball mill for secondary grinding;

[0014] S8: introducing the anode mud discharged from the ball mill in step S7 and the supernatant of the spiral classifier separated in step S6 into a filter press for anode mud filter press enrichment treatment, separating the anode mud filter press residue and the filter press liquid and collecting them for later use;

[0015] S9: the anode mud filter press residue separated in step S8 is returned to the liquid production plant, and the anode mud filter press residue is used as an oxidant instead of manganese powder at each manganese powder use point in the zinc leaching process and put into the acid leaching tank to enter the leaching process. The liquid after filter press is introduced into the liquid production plant and enters the leaching process as a solvent.

[0016] Preferably, the particle size of the anode mud after the primary grinding in the ball mill in step S3 is not less than 180 meshes, and the particle size of the anode mud after the secondary grinding in the ball mill in step S7 is not less than 200 meshes.

[0017] Preferably, the leaching time in step S9 is not less than 2 hours, and the leaching temperature is not less than 90°C.

[0018] The beneficial effects of the present invention are:

[0019] The present invention grinds the anode mud twice and filters the anode mud filter press residue after enrichment to return it to the liquid preparation plant, and uses the anode mud filter press residue as an oxidant instead of manganese powder at each manganese powder use point in the zinc leaching process to put it into the acid leaching tank to enter the leaching process, thereby effectively reducing the manganese powder consumption in the zinc leaching process, and the manganese leaching rate is high, and the utilization rate of manganese ions is effectively improved. The recovery and treatment process is simple, the production cost is low, and the problem of harm to human body by using hydrogen peroxide in the traditional recovery method and the problem of high electrolysis cost by using the electrolysis method are avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the process flow of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution, purpose achieved and effect of the present invention clear and easy to understand, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that technicians can understand.

[0022] It should be noted that in the description of the present invention, unless otherwise clearly defined or specified, the terms “installed”, “connected”, “connected”, “connected”, etc. should be understood in a broad sense, that is, it can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium.

[0023] In the present invention, if Figure 1 As shown, a method for recovering zinc electrowinning anode mud comprises the following steps:

[0024] S1: The anode plate with anode mud is placed in an anode cleaning and leveling machine for leveling and cleaning with high-pressure water. The cleaned anode plate is transported for standby use;

[0025] S2: the anode mud slurry formed after cleaning in step S1 is discharged into a spiral classifier for classification and filtration to separate the anode mud slurry and anode washing water;

[0026] S3: the anode mud slurry separated in step S2 is discharged into a ball mill for primary grinding, and the anode washing water is discharged into an anode washing water tank for storage;

[0027] S4: The anode mud in the electrolytic cell is discharged into the vacuum liquid receiving tank for collection and storage, and then introduced into the anode mud overflow tank;

[0028] S5: the anode mud discharged from the ball mill in step S3 and the anode mud discharged from the anode mud overflow tank in step S4 are uniformly introduced into the anode mud intermediate barrel for storage;

[0029] S6: the anode washing water in the anode washing tank in step S3 and the anode mud in the anode mud intermediate barrel in step S5 are simultaneously discharged into a spiral classifier for classification and filtration to separate the anode mud and the supernatant;

[0030] S7: discharging the anode mud separated in step S6 into a ball mill for secondary grinding;

[0031] S8: introducing the anode mud discharged from the ball mill in step S7 and the supernatant of the spiral classifier separated in step S6 into a filter press for anode mud filter press enrichment treatment, separating the anode mud filter press residue and the filter press liquid and collecting them for later use;

[0032] S9: the anode mud filter press residue separated in step S8 is returned to the liquid production plant, and the anode mud filter press residue is used as an oxidant instead of manganese powder at each manganese powder use point in the zinc leaching process and put into the acid leaching tank to enter the leaching process. The liquid after filter press is introduced into the liquid production plant and enters the leaching process as a solvent.

[0033] In this embodiment, the recovered anode mud is ground twice and filtered to enrich, and the anode mud filter press residue is returned to the liquid preparation plant. At each manganese powder use point in the zinc leaching process, the anode mud filter press residue is used as an oxidant instead of manganese powder and put into the acid leaching tank to enter the leaching process. In the zinc leaching process, MnO2 in the anode mud filter press residue reacts with the reducing agent SO2 under acidic conditions and is reduced to Mn 2+ , the main reactions are as follows:

[0034] MnO2+SO2+H2O=MnSO4+H2O;

[0035] SO2+H2O=H2SO3;

[0036] H2SO3+MnO2=MnSO4+H2O.

[0037] In this embodiment, by performing primary grinding on the anode mud cleaned from the anode plate with anode mud in step S3, the operating load of the ball mill when performing secondary grinding on the anode mud cleaned from the electrolytic cell in step S7 can be effectively reduced, and the consistency of the anode mud particle size after the two grindings can be effectively improved, thereby effectively improving the leaching rate of manganese in the anode mud filter press residue in the leaching process in step S9. Specifically, the particle size of the anode mud after the primary grinding by the ball mill in step S3 is 180 meshes, and the particle size of the anode mud after the secondary grinding by the ball mill in step S7 is 200 meshes. , after the two grindings in step S7, the anode mud particle size is 200 mesh; under the same other conditions, the longer the leaching time, the higher the manganese leaching rate. When the leaching time reaches 2h, the leaching time is further extended, and the change in the manganese leaching rate decreases. Therefore, the leaching time in step S9 of this embodiment is preferably 2h; under the same other conditions, the manganese leaching rate increases with the increase of the leaching temperature. When the leaching temperature is not less than 90°C, the manganese leaching rate can reach 90%. Therefore, the leaching temperature in step S9 of this embodiment is preferably 90°C. In the zinc leaching process, the anode mud filter press residue is used as an oxidant instead of manganese powder and is put into the acid leaching tank to enter the leaching process. Specifically, the anode mud particle size is 200 mesh, the leaching time is 2h, and the leaching temperature is 90°C. At this time, the manganese leaching rate can reach more than 93%, which effectively improves the manganese leaching rate, thereby effectively improving the efficiency of recovering lead and silver from the leaching residue in the subsequent process.

[0038] The present invention grinds the anode mud twice and filters the anode mud filter press residue after enrichment to return it to the liquid preparation plant, and uses the anode mud filter press residue as an oxidant instead of manganese powder at each manganese powder use point in the zinc leaching process to put it into the acid leaching tank to enter the leaching process, thereby effectively reducing the manganese powder consumption in the zinc leaching process, and the manganese leaching rate is high, and the utilization rate of manganese ions is effectively improved. The recovery and treatment process is simple, the production cost is low, and the problem of harm to human body by using hydrogen peroxide in the traditional recovery method and the problem of high electrolysis cost by using the electrolysis method are avoided.

[0039] Finally, it should be noted that although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present invention. Ordinary technicians in the field can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention, which should all be included in the scope of protection of this application.

Claims

1. A method for recovering zinc electrowinning anode mud, characterized in that: At least the following steps are included: S1: The anode plate with anode mud is placed in an anode cleaning and leveling machine for leveling and cleaning with high-pressure water. The cleaned anode plate is transported for standby use; S2: the anode mud slurry formed after cleaning in step S1 is discharged into a spiral classifier for classification and filtration to separate the anode mud slurry and anode washing water; S3: the anode mud slurry separated in step S2 is discharged into a ball mill for primary grinding, and the anode washing water is discharged into an anode washing water tank for storage; S4: The anode mud in the electrolytic cell is discharged into the vacuum liquid receiving tank for collection and storage, and then introduced into the anode mud overflow tank; S5: the anode mud discharged from the ball mill in step S3 and the anode mud discharged from the anode mud overflow tank in step S4 are uniformly introduced into the anode mud intermediate barrel for storage; S6: the anode washing water in the anode washing tank in step S3 and the anode mud in the anode mud intermediate barrel in step S5 are simultaneously discharged into a spiral classifier for classification and filtration to separate the anode mud and the supernatant; S7: discharging the anode mud separated in step S6 into a ball mill for secondary grinding; S8: introducing the anode mud discharged from the ball mill in step S7 and the supernatant of the spiral classifier separated in step S6 into a filter press for anode mud filter press enrichment treatment, separating the anode mud filter press residue and the filter press liquid and collecting them for later use; S9: the anode mud filter press residue separated in step S8 is returned to the liquid production plant, and the anode mud filter press residue is used as an oxidant instead of manganese powder at each manganese powder use point in the zinc leaching process and put into the acid leaching tank to enter the leaching process. The liquid after filter press is introduced into the liquid production plant and enters the leaching process as a solvent.

2. A zinc electrodeposition anode slime recovery and treatment method according to claim 1, characterized in that: The particle size of the anode mud after the primary grinding by the ball mill in step S3 is not less than 180 meshes, and the particle size of the anode mud after the secondary grinding by the ball mill in step S7 is not less than 200 meshes.

3. A zinc electrodeposition anode slime recovery and treatment method according to claim 1 or 2, characterized in that: The leaching time in step S9 is not less than 2 hours, and the leaching temperature is not less than 90°C.

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