Efficient comprehensive recovery method for valuable metals in zinc oxide smoke dust

Abstract

The invention belongs to the technical field of metallurgical resource recovery, and discloses an efficient comprehensive recovery method for valuable metals in zinc oxide smoke dust, which comprises the steps of neutral leaching of zinc oxide smoke dust, low-acid leaching, high-acid leaching, neutralization and precipitation, arsenic removal by ferric salt and the like, by adopting the method, the recovery rate of zinc in the zinc oxide smoke dust reaches 98%, the recovery rate of lead reaches 98%, the recovery rate of silver reaches 98%, and the recovery rate of valuable metals in the zinc oxide smoke dust reaches 98%. The recovery rate of indium reaches 90% or above, the comprehensive slag rate can be reduced to 30%, the recovery rate of all valuable metals in the zinc oxide smoke dust is remarkably increased, the resource utilization rate is increased, and resource waste is reduced. And on the basis of optimizing experimental conditions, the production cost is reduced, and the economic benefit is improved. Meanwhile, the method is high in recovery efficiency, low in safety risk, low in investment and suitable for industrial application, and has obvious economic benefits and popularization values.

Description

Technical Field

[0001] The present invention relates to the technical field of metallurgical resource recovery, and particularly to a method for efficiently comprehensively recovering valuable metals from zinc oxide fume Background Art

[0002] With the acceleration of the global industrialization process, the consumption rate of metal resources has increased sharply. Metals such as zinc, lead, indium, and germanium are widely used in many fields, such as the electronics, automotive, and construction industries, and are indispensable basic materials. However, the ore reserves of these metals are limited. After long-term mining, high-quality ores have gradually decreased, and the resource supply pressure has increased. Zinc oxide fume, as a by-product in the metallurgical process, contains valuable metals equivalent to secondary resources. Recycling it can, to a certain extent, relieve the pressure of resource shortage. The traditional ways of treating zinc oxide fume are mainly stacking or simple landfill. These fumes contain harmful substances such as heavy metals. During natural processes such as rainwashing and weathering, heavy metals will gradually be released into the soil, water body, and atmosphere, causing serious harm to the ecological environment and human health. In order to address environmental pollution problems, governments of various countries have successively introduced strict environmental protection regulations, requiring enterprises to carry out harmless treatment and resource utilization of industrial wastes, which has prompted enterprises to carry out comprehensive recovery projects for valuable metals in zinc oxide fume.

[0003] During the smelting process of metals such as zinc and lead, a large amount of zinc oxide fume will be generated. For example, during the pyrometallurgical zinc smelting process, zinc concentrate will produce fumes containing valuable metals such as zinc, lead, indium, and germanium after roasting. If these fumes are not recycled, it will not only cause resource waste, but also increase the production cost and environmental protection pressure of enterprises. Therefore, from the perspective of the interests and sustainable development of metallurgical enterprises themselves, there is also an urgent need to comprehensively recover valuable metals from zinc oxide fume to improve the resource utilization rate and economic benefits of the entire metallurgical production process. Summary of the Invention

[0004] The purpose of the present invention is to address the problems existing in the existing technology for comprehensively recovering valuable metals from zinc oxide fume, and provide a method for efficiently comprehensively recovering lead-silver slag and indium-germanium slag, so as to solve problems such as the environmental pollution caused by valuable metals in zinc oxide fume, the inability to comprehensively recycle fully utilized resources, and the improvement of the recovery rate of valuable metals by optimizing experimental conditions.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A method for efficiently comprehensively recovering valuable metals from zinc oxide fume, comprising the following steps:

[0007] (1) Neutral leaching: First, the zinc oxide dust is pretreated to remove impurities and ground into lumps. Based on the zinc concentration in the middle supernatant, an oxidation solution with a corresponding concentration is prepared using electrolytic waste liquid. According to the experimental conditions, the reaction is carried out at a certain temperature for a certain time. After the reaction, it is allowed to stand and filtered. The filtrate is the middle supernatant, which is sent to the purification system, and the filter residue is the neutral leaching residue, which is used for the next step of low-acid leaching.

[0008] (2) Low-acid leaching: According to the amount of neutral leaching residue, an initial low-acid leaching solution with a certain concentration is prepared using 98% industrial sulfuric acid at a certain liquid-solid ratio. The reaction is carried out at a certain temperature for a certain time. After the reaction, it is allowed to stand and filtered. The filtrate is the low-acid leaching solution, which is returned to the neutral leaching process, and the filter residue is used for the next step of high-acid leaching.

[0009] (3) High-acid leaching: According to the amount of low-acid leaching residue, an initial high-acid leaching solution with a certain concentration is prepared using electrolytic waste liquid at a certain concentration. The reaction is carried out at a certain temperature for a certain time. After the reaction, it is allowed to stand and filtered. The filtrate is the high-acid leaching solution, which is returned to the low-acid leaching process. The filter residue is dried, the mass is recorded, and then it is sent for sample testing to calculate the recovery rate of rare and precious metals. The filter residue is lead-silver slag, which is sold externally.

[0010] (4) Neutralization precipitation: The low-acid leaching solution is enriched through three cycles, and the indium concentration in the acid leaching solution is increased to 1 g / L. Then, germanium and indium are precipitated by neutralization, and the indium and germanium in the acid leaching solution are enriched into the neutralization slag, which is sold externally.

[0011] (5) Iron salt arsenic removal: The neutralized solution in step (4) is used for iron salt arsenic removal.

[0012] Further, in step (1) of neutral leaching, the zinc oxide dust is pretreated. The concentration of the oxidation solution is prepared to be 130 g / L, and the volume is measured to be 3 L. The temperature is heated to 60 °C through a constant-temperature heating plate, zinc oxide is slowly added, the pH is adjusted to 2 - 3, potassium permanganate of 1% of the added zinc oxide amount is added. After reacting for 30 min, zinc oxide is continuously added to adjust the pH to 4.5. After reacting for 90 min, the end-point pH is controlled at 5.0, and the reaction temperature during the process is controlled at 65 - 70 °C. At this time, the neutral leaching process is completed, and it is allowed to stand and filtered. The filtrate is the middle supernatant, which is sent to the purification system, and the filter residue is used for the next process of low-acid leaching.

[0013] Further, in step (2) of low-acid leaching, the neutral leaching residue obtained in step (1) is used, and the control conditions are as follows: the concentration of the acid leaching initial solution is 40 g / L, the liquid-solid ratio is controlled at 5:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, it is allowed to stand and filtered. The filtrate is the low-acid leaching solution, which is returned to the neutral leaching process for recycling, and the filter residue is the low-acid leaching residue, which is used for the next process of high-acid leaching.

[0014] Further, in step (3), high-acid leaching is carried out using the low-acid leaching residue obtained in step (2), and the conditions are controlled as follows: The initial acid solution with an acid concentration of 120 g / L is prepared using electrolytic waste liquid, the liquid-solid ratio is controlled at 3:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, it is allowed to stand and filtered. The filtrate is returned to the low-acid leaching process for recycling, and the filter residue is lead-silver slag. After drying, the mass is recorded and the contents of precious and rare metals such as zinc, lead, silver, and indium are detected, and the lead-silver slag is sold externally.

[0015] Further, in step (4), neutralization precipitation is carried out using the low-acid leaching solution obtained in step (2), and the conditions are controlled as follows: First, the low-acid leaching solution is heated to 60 °C by a constant-temperature heating plate, zinc oxide is slowly added to adjust the pH to 2.5, tannic acid 40 times the content of germanium in the low-acid leaching solution is added, the reaction time is 60 min, then zinc oxide is continuously added to adjust the pH to 4.0, the process temperature is controlled at 50 - 60 °C, the reaction time is 60 min. After the reaction, it is allowed to stand and filtered. The filtrate is the neutralized solution, which is used for the next step of iron salt arsenic removal, and the filter residue is indium-germanium slag, which is sold externally.

[0016] Further, in step (5), iron salt arsenic removal is carried out using the neutralized solution in step (4), and the conditions are as follows: The neutralized solution is heated to 60 - 70 °C by a constant-temperature heating plate, ferrous sulfate 30 times the content of arsenic in the neutralized solution is added, the reaction time is 180 min. After the reaction, it is allowed to stand and filtered. The filtrate is returned to the medium leaching process for recycling, and the filter residue is arsenic slag, which is landfilled.

[0017] In the above step (1), the zinc oxide fume is prepared in the self-owned slag treatment workshop.

[0018] The above industrial 98% sulfuric acid is a by-product of the acid-making process of a zinc hydrometallurgy enterprise and does not need to be purchased externally.

[0019] The heating sources for the above leaching and neutralization processes are provided by the self-owned constant-temperature heating plate.

[0020] In summary, due to the adoption of the above technical solution, the present invention comprehensively recovers valuable metals in the zinc oxide fume. The zinc recovery rate in the zinc oxide fume reaches 98%, the lead recovery rate reaches 98%, the silver recovery rate reaches 98%, the indium recovery rate is above 90%, and the comprehensive slag rate can be reduced to 30%, significantly improving the recovery rates of various valuable metals in the zinc oxide fume.

[0021] The main advantages of this method include: 1. It can effectively improve the leaching rates of valuable metals such as zinc and indium in zinc oxide fume, fully recover resources, and enhance economic benefits; 2. It can effectively recover multiple valuable metals. While recovering zinc, indium, and germanium, it can also effectively recover valuable metals such as lead and silver; 3. Compared with some traditional processes, this method can reduce energy consumption during the leaching process; 4. During the neutralization precipitation process, by controlling the reaction conditions, valuable metals can be precipitated, while reducing the discharge of pollutants such as wastewater and waste residue, reducing the harm to the environment, and meeting environmental protection requirements; 5. This method has good adaptability to zinc oxide fume with different compositions and properties, can be adjusted and optimized according to the specific raw material situation, and achieve efficient recovery of valuable metals; 6. This method is simple and reliable in operation, overall reduces production costs, improves the economy and competitiveness of the process, and is very suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The present invention will be described in detail below in conjunction with the drawings and specific embodiments. Here, the schematic embodiments of the present invention and the description are used to explain the present invention, but do not limit the present invention.

[0024] Example 1

[0025] Raw materials: Zinc oxide fume, Zn 64.58%, Pb 12.87%, Ag 0.15%, In 0.048%, Ge 0.0024%.

[0026] (1) In neutral leaching, the zinc oxide fume is pretreated. The concentration of the oxidation solution is prepared at 130 g / L, and the volume is measured at 3 L. The temperature is heated to 60 °C by a constant temperature heating plate. Zinc oxide is slowly added, and the pH is adjusted to 2 - 3. Potassium permanganate at 1% of the zinc oxide addition amount is added. After reacting for 30 min, zinc oxide is continuously added to adjust the pH to 4.5. After reacting for 90 min, the end-point pH is controlled at 5.0, and the reaction temperature during the process is controlled at 65 - 70 °C. At this time, the neutral leaching process is completed, and it is left to stand for filtration. The filtrate is the middle supernatant, which is sent to the purification system, and the filter residue is used for the next process of low-acid leaching. The amount of zinc oxide added is 405 g.

[0027] (2) Low-acid leaching: According to the amount of neutral leaching residue, the initial concentration of the acid leaching solution is 40 g / L, the liquid-solid ratio is controlled at 5:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction ends, it is left to stand for filtration. The filtrate is the low-acid leaching solution, which is returned to the neutral leaching process for recycling, and the filter residue is the low-acid leaching residue, which is used for the next process of high-acid leaching.

[0028] (3) High-acid leaching: According to the amount of low-acid leaching residue, an initial acid solution with a concentration of 120 g / L is prepared from the electrolytic waste liquid. The liquid-solid ratio is controlled at 3:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, it is left to stand and filtered. The filtrate is returned to the low-acid leaching process for recycling. The filter residue is lead-silver slag, which is dried, weighed, and the contents of precious and rare metals such as zinc, lead, silver, and indium are detected. The lead-silver slag is sold externally.

[0029] (4) Neutralization precipitation: The low-acid leaching solution is heated to 60 °C by a constant-temperature heating plate, zinc oxide is slowly added to adjust the pH to 2.5, tannic acid 40 times the content of germanium in the low-acid leaching solution is added, and the reaction time is 60 min. Then zinc oxide is continuously added to adjust the pH to 4.0. The process temperature is controlled at 50 - 60 °C, and the reaction time is 60 min. After the reaction, it is left to stand and filtered. The filtrate is the neutralized solution, which is used for the next process of arsenic removal by ferric salt. The filter residue is indium-germanium slag, which is sold externally.

[0030] The results show that: by using the above method, the recovery rates of zinc, lead, silver, indium, and germanium in the zinc oxide fume dust reach 98.24%, 92.63%, 91.58%, 92.65%, and 75.68% respectively, and the indium content in the neutralization slag is 1.58%.

[0031] Example 2

[0032] Raw materials: Zinc oxide fume dust, Zn 65.32%, Pb 15.49%, Ag 0.12%, In 0.053%, Ge 0.0025%.

[0033] (1) In neutral leaching, the zinc oxide fume dust is pretreated, the oxidation solution concentration is prepared at 130 g / L, the volume is measured as 3 L, the temperature is heated to 60 °C by a constant-temperature heating plate, zinc oxide is slowly added, the pH is adjusted to 2 - 3, potassium permanganate 1% of the amount of zinc oxide added is added, after reacting for 30 min, zinc oxide is continuously added to adjust the pH to 4.5, after reacting for 90 min, the end-point pH is controlled at 5.0, and the reaction temperature during the process is controlled at 65 - 70 °C. At this time, the neutral leaching process is completed, and it is left to stand and filtered. The filtrate is the middle supernatant, which is sent to the purification system, and the filter residue is used for the next process of low-acid leaching. The amount of zinc oxide added is 410 g.

[0034] (2) Low-acid leaching: According to the amount of neutral leaching residue, the initial acid leaching solution concentration is 40 g / L, the liquid-solid ratio is controlled at 5:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, it is left to stand and filtered. The filtrate is the low-acid leaching solution, which is returned to the neutral leaching process for recycling. The filter residue is the low-acid leaching residue, which is used for the next process of high-acid leaching.

[0035] (3) High-acid leaching: According to the amount of low-acid leaching residue, an initial acid solution with a concentration of 120 g / L is prepared from the electrolytic waste liquid. The liquid-solid ratio is controlled at 3:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, it is allowed to stand and filtered. The filtrate is returned to the low-acid leaching process for recycling. The filter residue is lead-silver slag, which is dried, weighed, and the contents of precious and rare metals such as zinc, lead, silver, and indium are detected. The lead-silver slag is sold externally.

[0036] (4) Neutralization precipitation: The low-acid leaching solution is heated to 60 °C by a constant-temperature heating plate, zinc oxide is slowly added to adjust the pH to 2.5, tannic acid 40 times the content of germanium in the low-acid leaching solution is added, the reaction time is 60 min, then zinc oxide is continuously added to adjust the pH to 4.0, the process temperature is controlled at 50 - 60 °C, the reaction time is 60 min. After the reaction, it is allowed to stand and filtered. The filtrate is the neutralized solution, which is used for the next step of iron salt arsenic removal. The filter residue is indium-germanium slag, which is sold externally.

[0037] The results show that: by using the above method, the recovery rates of zinc, lead, silver, indium, and germanium in the zinc oxide fume and dust reach 98.67%, 93.21%, 90.38%, 93.74%, and 72.34% respectively, and the indium content in the neutralization slag is 1.67%.

[0038] Example 3

[0039] Raw materials: Zinc oxide fume and dust, Zn 69.41%, Pb 12.84%, Ag 0.11%, In 0.061%, Ge 0.0023%.

[0040] (1) In neutral leaching, the zinc oxide fume and dust are pretreated, the oxidation solution concentration is prepared at 130 g / L, the volume is measured at 3 L, the temperature is heated to 60 °C by a constant-temperature heating plate, zinc oxide is slowly added to adjust the pH to 2 - 3, potassium permanganate 1% of the amount of zinc oxide added is added, after reacting for 30 min, zinc oxide is continuously added to adjust the pH to 4.5, after reacting for 90 min, the end-point pH is controlled at 5.0, the reaction temperature during the process is controlled at 65 - 70 °C. At this time, the neutral leaching process is completed, and it is allowed to stand and filtered. The filtrate is the middle supernatant, which is sent to the purification system, and the filter residue is used for the next step of low-acid leaching. The amount of zinc oxide added is 400 g.

[0041] (2) Low-acid leaching: According to the amount of neutral leaching residue, the initial acid leaching solution concentration is 40 g / L, the liquid-solid ratio is controlled at 5:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, it is allowed to stand and filtered. The filtrate is the low-acid leaching solution, which is returned to the neutral leaching process for recycling. The filter residue is the low-acid leaching residue, which is used for the next step of high-acid leaching.

[0042] (3) High-acid leaching: According to the amount of low-acid leaching residue, an initial acid solution with a concentration of 120 g / L is prepared from the electrolytic waste liquid, the liquid-solid ratio is controlled at 3:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, it is left to stand and filtered. The filtrate is returned to the low-acid leaching process for recycling. The filter residue is lead-silver slag. After drying, its mass is recorded and the contents of precious and rare metals such as zinc, lead, silver, and indium are detected. The lead-silver slag is sold externally.

[0043] (4) Neutralization precipitation: The low-acid leaching solution is heated to 60 °C by a constant-temperature heating plate, zinc oxide is slowly added to adjust the pH to 2.5, tannic acid 40 times the content of germanium in the low-acid leaching solution is added, the reaction time is 60 min, then zinc oxide is continuously added to adjust the pH to 4.0, the process temperature is controlled at 50 - 60 °C, and the reaction time is 60 min. After the reaction, it is left to stand and filtered. The filtrate is the neutralized solution, which is used for the next step of arsenic removal by iron salt. The filter residue is indium-germanium slag, which is sold externally.

[0044] The results show that: by using the above method, the recovery rates of zinc, lead, silver, indium, and germanium in zinc oxide fume dust reach 99.12%, 94.13%, 93.42%, 91.26%, and 75.69% respectively, and the indium content in the neutralization slag is 1.83%.

[0045] The above has introduced the technical solutions provided by the embodiments of the present invention in detail. Specific examples are used in this article to elaborate on the principles and implementation manners of the embodiments of the present invention. The descriptions of the above embodiments are only applicable to helping understand the principles of the embodiments of the present invention. At the same time, for those of ordinary skill in the art, based on the embodiments of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for efficient comprehensive recovery of valuable metals from zinc oxide fume, comprising the following steps: (1) Neutral leaching: Pretreat the zinc oxide fume, remove impurities and grind it into pieces. Based on the zinc concentration in the middle supernatant, prepare an oxidation solution with a corresponding concentration using electrolytic waste liquid. React at a certain temperature for a certain time according to the experimental conditions. After the reaction, let it stand and filter. The filtrate is the middle supernatant, which is sent to the purification system. The filter residue is the neutral leaching residue and is used for the next step of low-acid leaching; (2) Low-acid leaching: According to the amount of the neutral leaching residue, prepare an initial low-acid leaching solution with a certain concentration using 98% industrial sulfuric acid at a certain liquid-solid ratio. React at a certain temperature for a certain time. After the reaction, let it stand and filter. The filtrate is the low-acid leaching solution, which is returned to the neutral leaching process. The filter residue is used for the next step of high-acid leaching; (3) High-acid leaching: According to the amount of the low-acid leaching residue, prepare an initial high-acid leaching solution with a certain concentration using electrolytic waste liquid at a certain concentration. React at a certain temperature for a certain time. After the reaction, let it stand and filter. The filtrate is the high-acid leaching solution, which is returned to the low-acid leaching process. The filter residue is dried, its mass is recorded, and then it is sent for sample testing to calculate the recovery rate of rare and precious metals. The filter residue is the lead-silver slag and is sold externally; (4) Neutralization precipitation: The low-acid leaching solution is enriched through three cycles to increase the indium concentration in the acid leaching solution to 1 g / L, and then germanium and indium are precipitated by neutralization. The indium and germanium in the acid leaching solution are enriched in the neutralization residue and then sold externally.

2. The high-efficiency comprehensive recovery method for valuable metals from zinc oxide fume according to claim 1, characterized in that: In step (1) of neutral leaching, after the zinc oxide fume is pretreated, the concentration of the oxidation solution is prepared to be 130 g / L, and the volume is measured to be 3.5 L. The temperature is heated to 60 °C through a constant-temperature heating plate, zinc oxide is slowly added, the pH is adjusted to 2 - 3, potassium permanganate accounting for 1% of the amount of zinc oxide added is added. After reacting for 30 min, zinc oxide is continuously added to adjust the pH to 4.

5. After reacting for 90 min, the end-point pH is controlled at 5.0, and the reaction temperature during the process is controlled at 65 - 70 °C. At this time, the neutral leaching process is completed. Let it stand and filter. The filtrate is the middle supernatant, which is sent to the purification system. The filter residue is used for the next process of low-acid leaching.

3. A method for highly efficient comprehensive recovery of valuable metals from zinc oxide fume, according to claim 1, characterized in that: In step (2) of low-acid leaching, the neutral leaching residue obtained in step (1) is used, and the control conditions are as follows: the concentration of the initial acid leaching solution is 40 g / L, the liquid-solid ratio is controlled at 5:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, let it stand and filter. The filtrate is the low-acid leaching solution, which is returned to the neutral leaching process for recycling. The filter residue is the low-acid leaching residue and is used for the next process of high-acid leaching.

4. A method for efficient comprehensive recovery of valuable metals from zinc oxide fume according to claim 1, characterized in that: In step (3) of high-acid leaching, the low-acid leaching residue obtained in step (2) is used, and the control conditions are as follows: Prepare an initial acid solution with an acid concentration of 120 g / L using electrolytic waste liquid, the liquid-solid ratio is controlled at 3:1, the reaction temperature during the process is controlled at 80 - 85 °C, the reaction time is 120 min. After the reaction, let it stand and filter. The filtrate is returned to the low-acid leaching process for recycling. The filter residue is the lead-silver slag, which is dried, its mass is recorded, and the contents of rare and precious metals zinc, lead, silver, and indium are detected. The lead-silver slag is sold externally.

5. The method for highly efficient comprehensive recovery of valuable metals from zinc oxide fume according to claim 1, characterized in that: Step (4) uses the low-acid leaching solution obtained in step (2) for neutralization precipitation, and the control conditions are as follows: The low-acid leaching solution is heated to 60 °C by a constant-temperature heating plate, zinc oxide is slowly added to adjust the pH to 2.5, tannic acid 40 times the germanium content in the low-acid leaching solution is added, the reaction time is 60 min, zinc oxide is continuously added to adjust the pH to 4.0, the process temperature is controlled at 50 - 60 °C, the reaction time is 60 min, after the reaction is completed, it is left to stand for filtration, the filtrate is the neutralized solution, which is used for iron salt arsenic removal in the next process, and the filter residue is indium-germanium residue, which is sold externally.

6. The high-efficiency comprehensive recovery method of valuable metals from zinc oxide fume according to claim 1, characterized in that: Step (5) uses the neutralized solution in step (4) for iron salt arsenic removal, and the control conditions are: The neutralized solution is heated to 60 - 70 °C by a constant-temperature heating plate, ferrous sulfate 30 times the arsenic content in the neutralized solution is added, the reaction time is 180 min, after the reaction is completed, it is left to stand for filtration, the filtrate is returned to the medium leaching process for recycling, and the filter residue is arsenic residue, which is landfilled.

7. A method for efficiently comprehensively recovering valuable metals from zinc oxide fume according to claim 2, characterized in that: In the neutral leaching process, most of the zinc is dissolved into zinc sulfate, and indium, germanium, lead, and indium are enriched in the neutral leaching residue. Through acid leaching, indium and germanium are leached out, and lead and silver in the residue are enriched. Then, through neutralization precipitation, indium and germanium are enriched in the residue, and zinc enters the large system while realizing the efficient comprehensive recovery of lead-silver residue and indium-germanium residue.

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