Method for comprehensively recovering low-grade lead-zinc oxidized ore resources

Abstract

The invention relates to the technical field of non-ferrous metal metallurgy, in particular to a comprehensive recovery method for low-grade lead-zinc oxidized ore resources. According to the method, through a side-blown smelting furnace oxidation process and a fuming furnace reduction process, firstly, pyrometallurgy oxygen-enriched smelting is carried out, high-lead smoke dust and zinc-germanium-containing slag are produced, zinc oxide smoke dust is obtained through fuming reduction volatilization, then the zinc oxide smoke dust enters a zinc hydrometallurgy process, the high-lead smoke dust enters a pyrometallurgy lead smelting process for batching, and the zinc-germanium-containing slag is obtained. And finally, lead metal (rich in silver), zinc metal, germanium concentrate and tailings are generated. The method aims at achieving comprehensive recovery of low-grade lead-zinc oxidized ore resources by improving the recovery rate of lead and zinc in the low-grade lead-zinc oxidized ore and conducting cooperative treatment on silver, germanium and cadmium at the same time, and a new thought is provided for comprehensive recovery and large-scale industrial production of the low-grade lead-zinc oxidized ore resources.

Description

Technical Field

[0001] This invention relates to the field of non-ferrous metal smelting technology, and in particular to a method for the comprehensive recovery of low-grade lead-zinc oxide ore resources. Background Technology

[0002] my country possesses abundant lead-zinc mineral resources, but the majority are low-grade ores with limited high-grade ones. Low-grade ores are structurally complex and often contain impurities such as fluorine, chlorine, arsenic, cadmium, and mercury, making them difficult to process. Currently, domestic lead-zinc smelting enterprises generally face problems such as raw material shortages, declining concentrate grades, high procurement costs for high-grade ore, high impurity content in low-grade lead-zinc ores, and high overall energy consumption in smelting. Lead-zinc enterprises are gradually shifting their smelting raw materials from high-grade lead sulfide concentrate to medium- and low-grade lead sulfide concentrate, then to lead oxide concentrate, zinc oxide concentrate, lead-zinc oxide ore, leaching slag, and secondary zinc-containing materials such as steel mill zinc dust. Some enterprises rely on imported lead-zinc concentrate. With the continuous growth of my country's lead-zinc smelting capacity, the contradiction between high-grade, high-quality lead-zinc mineral resources and the raw material shortage for smelting enterprises is becoming increasingly prominent, forcing them to smelt low-grade, complex lead-zinc oxide ore and high-fluorine and chlorine zinc oxide dust. Therefore, improving the comprehensive recycling technology of low-grade lead-zinc resources aligns with the new trend of industry development. At present, although my country has made breakthroughs in the beneficiation technology of lead-zinc oxide ore, the lead-zinc metal recovery rate is only about 80%, and there are problems such as high energy consumption and large slag volume in smelting low-grade lead-zinc oxide ore.

[0003] The main smelting methods for low-grade lead-zinc oxide ore resources include pyrometallurgical processes and hydrometallurgical processes. Among them, Chinese patent CN106086457A (a method for the resource utilization of low-grade lead-zinc oxide ore) achieves the utilization of low-grade lead-zinc oxide ore resources. However, the use of rotary kilns results in low recovery rates of associated rare and precious metals such as silver, germanium, and indium, low zinc recovery efficiency, and high labor intensity in cleaning kiln deposits.

[0004] Furthermore, Chinese patent CN108456775B (A method for combined side-blown chemical processing and fuming furnace refining of zinc-containing materials) proposes to mix zinc-containing materials such as lead-zinc symbiotic ores and zinc leaching slag in any proportion, add them to a side-blown furnace for chemical processing, and obtain zinc oxide dust with high F, Cl, and As content; the slag is directly fed into a fuming furnace for refining, and the flue gas from the fuming furnace is treated to obtain zinc oxide dust with low F, Cl, and As content. However, this process is mainly for lead-zinc symbiotic ores containing F, Cl, and As, and the arbitrary mixing of raw materials is detrimental to the recovery rate of precious metals such as lead, zinc, silver, germanium, and indium in low-grade lead-zinc oxide ores. The F and Cl impurities cannot be ignored in the problem of electrolytic sticking in zinc hydrometallurgical processes.

[0005] Therefore, it is necessary to propose a comprehensive resource recovery method for low-grade lead-zinc oxide ores to improve the recovery rate of lead and zinc in low-grade lead-zinc oxide ores, while simultaneously co-processing silver, germanium, and cadmium, thereby achieving comprehensive recovery of low-grade lead-zinc oxide ores.

[0006] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0007] The main objective of this application is to provide a comprehensive recovery method for low-grade lead-zinc oxide ore resources. The method aims to improve the recovery rate of lead and zinc in low-grade lead-zinc oxide ore, while simultaneously co-processing silver, germanium, and cadmium, thereby achieving comprehensive recovery of low-grade lead-zinc oxide ore resources and providing a new approach for the large-scale industrial production of comprehensive recovery of low-grade lead-zinc oxide ore resources.

[0008] To achieve the above objectives, the present invention provides a comprehensive recovery method for low-grade lead-zinc oxide ore resources, the method comprising the following steps: S1, low-grade lead-zinc oxide ore, wet zinc leaching residue, iron slag, lump coal, quartz sand and secondary zinc-containing materials are mixed in a mass ratio of 4:4:2:2:2:1 to obtain a mixed ore; The low-grade lead-zinc oxide ore has a combined lead and zinc grade greater than 10% and a calcium grade less than 35%. The secondary zinc-containing materials include any two or more of zinc-containing iron slag, zinc-containing sulfuric acid slag, and pyrometallurgical lead smelting slag. S2, the mixed ore described in S1 is fed into a side-blown smelting furnace to obtain high-lead flue dust and liquid zinc-containing slag; S3, the liquid zinc-containing slag described in S2 is sent to the fuming furnace A, and zinc oxide dust A is obtained after smelting; S4, the high-lead dust mentioned in S2 is mixed with lead slag, iron slag and lead concentrate in a mass ratio of 1:1:1:2 and then fed into a top-blown smelting furnace to obtain molten lead-rich slag. The molten lead-rich slag is then periodically transported to a side-blown reduction furnace to obtain crude lead and reduction slag. After the crude lead is electrolytically smelted and die-cast, lead ingots and silver ingots are obtained. S5, the reducing slag described in S4 is periodically fed into the fuming furnace B to obtain zinc oxide dust B; S6, the zinc oxide dust A and zinc oxide dust B are fed into the hydrometallurgical zinc smelting system to obtain germanium concentrate, zinc-containing filtrate, iron slag and lead slag. The lead slag and iron slag are returned to S4 for batching. The zinc-containing filtrate is purified and impurities are removed to obtain supernatant and germanium-containing filter residue. The germanium-containing filter residue was calcined to obtain germanium concentrate; The supernatant is purified and electrolytically melted to obtain zinc ingots.

[0009] Optionally, the mass ratio of FeO to SiO2 in the mixed ore is (1.3-1.5):1, and the mass ratio of CaO to SiO2 is (0.5-0.8):1.

[0010] Optionally, in the fuming furnace A described in S3, a high-pressure air flow of 24,000 m³ / h and pulverized coal flow of 4.5 t / h are introduced, the furnace temperature is 1150–1250℃, and the smelting cycle is 3 hours per furnace.

[0011] Optionally, pulverized coal is injected into the top-blown smelting furnace in S4, and the temperature is controlled at 950-1050℃. The conveying cycle of the molten lead-rich slag is 2.5-3.5 hours, and the temperature in the side-blown reduction furnace is 1050-1200℃.

[0012] Optionally, pulverized coal and high-pressure air are introduced into the fuming furnace B described in S5, the smelting temperature is 1100-1250℃, and the smelting cycle is 1.5-3h / furnace.

[0013] Optionally, the calorific value of the pulverized coal is 4000–6500 kcal·kg⁻¹. -1 The pulverized coal has a fixed carbon content of ≥50%, an sulfur content of ≤2.5%, a volatile matter content of 10% to 25%, a moisture content of ≤2%, an ash content of ≤30%, and a particle size of ≤200 mesh accounting for more than 70% of the total volume of pulverized coal.

[0014] Optionally, the pulverized coal supply system is a Redek pulverized coal injection system, with a pulverized coal feed rate of 2 to 5.5 t / h.

[0015] Optionally, the particle size of the low-grade lead-zinc oxide ore in S1 is ≤10mm; the moisture content of the secondary zinc-containing material is 10% to 18%; and the moisture content of the mixed ore is <18%.

[0016] Optionally, the smelting temperature of the side-blown smelting furnace described in S2 is 1150–1350°C, and the smelting cycle is 2–4 hours per furnace.

[0017] Optionally, smelting waste slag is generated in the smelting furnace A and the smelting furnace B. The smelting waste slag is water-quenched to obtain water-quenched slag, which is recycled as a raw material for cement building materials.

[0018] Invention principle: Low-grade lead-zinc oxide ores contain elements such as lead, zinc, gold, silver, germanium, cadmium, arsenic, sulfur, thallium, fluorine, chlorine, iron, silicon, calcium, aluminum, and magnesium. Based on the different physicochemical properties of these elements and the varying levels of valuable metal content, a combined smelting process is determined. First, a high-temperature oxidation-reduction smelting process using a side-blown furnace is employed. Lead, zinc, gold, silver, germanium, cadmium, and arsenic are introduced into the intermediate product dust, while impurities such as thallium, fluorine, and chlorine are separated and introduced into the flue gas. Sulfur from the oxide ore is fed into a medium-concentration flue gas sulfuric acid production system as sulfur dioxide flue gas to produce concentrated sulfuric acid. Impurities such as iron, silicon, calcium, aluminum, and magnesium oxides are separated and slag is formed. Then, leveraging the advantages of the lead-zinc combined smelting process, pyrometallurgical smelting of lead, gold, and silver produces crude lead, while hydrometallurgical smelting produces zinc, cadmium, and germanium, ultimately achieving the goal of comprehensively recovering valuable metals such as lead, zinc, gold, silver, germanium, and cadmium. The lower the lead and zinc grade in the oxide ore, the higher the content of iron, silicon, calcium, aluminum, and magnesium elements, the more difficult the smelting process control, the lower the metal recovery rate, the higher the energy consumption, and the higher the waste slag production.

[0019] This application provides a method for the comprehensive recovery of low-grade lead-zinc oxide ore resources, which has at least the following beneficial effects: 1. This application involves mixing low-grade lead-zinc oxide ore with other materials in a specific ratio, then melting all materials in a side-blown smelting furnace and conducting a preliminary reaction. The resulting slag flows into a fuming furnace. In the fuming furnace, the metals in the slag are further reduced and volatilized, ultimately yielding a high-purity metal product. The integrated recovery process of the side-blown smelting furnace and the fuming furnace combines the advantages of the side-blown smelting furnace's wide applicability of raw materials and the fuming furnace's high metal recovery rate and large production capacity. This improves the recovery rate of lead and zinc in low-grade lead-zinc oxide ore and simultaneously co-processes silver, germanium, and cadmium, achieving comprehensive recovery of low-grade lead-zinc oxide ore resources. 2. This application uses a side-blown smelting furnace to send sulfur from oxidized ore into a medium-concentration flue gas acid production system in the form of sulfur dioxide flue gas. Compared with the traditional low-concentration sulfur dioxide flue gas entering the tail gas desulfurization system, the tail gas treatment cost is lower and it is more suitable for large-scale industrial production. 3. This application recovers lead, zinc, silver and germanium metals through a comprehensive recycling process using a side-blown smelting furnace and a fuming furnace. Compared with the direct smelting process using a fuming furnace, the mineral processing capacity is large, which allows valuable metals in low-grade lead and zinc oxide ores to be comprehensively recycled and utilized through the comprehensive recycling process, making it suitable for large-scale industrial production. 4. This application controls the proportion of mixed ore raw materials, the slag type, smelting temperature and smelting cycle in the process, and regulates the key process control parameters in the entire lead-zinc smelting system, so that the lead recovery rate in low-grade lead-zinc oxide ore is greater than 95% and the zinc recovery rate is greater than 93%. Compared with the traditional process of directly smelting low-grade oxide ore in a fuming furnace, the lead and zinc recovery rates are improved. 5. This application directly sells lead ingots, zinc ingots and germanium concentrate, and uses the tailings of the fuming furnace as raw materials for the building materials and cement industries, generating zero hazardous waste and zero solid waste. 6. This application is applicable to the smelting of all low-grade lead-zinc oxide ores with a total lead-zinc content >10%, and no longer strictly limits whether the zinc content is greater than the lead content. In contrast, the traditional rotary kiln process requires the total lead-zinc content of the raw material to reach more than 48% and the zinc content to be greater than the lead content. Compared with the two, the raw material applicability of this application is wider. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the process of the present invention.

[0021] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0022] To better understand the above technical solutions, exemplary embodiments of this disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of this disclosure to those skilled in the art.

[0023] Test Procedure S1, low-grade lead-zinc oxide ore, hydrometallurgical zinc leaching slag, iron slag, lump coal, quartz sand, and secondary zinc-containing materials are mixed in a mass ratio of 4:4:2:2:2:1 to obtain a mixed ore; the particle size of the low-grade lead-zinc oxide ore is ≤10mm; the sum of lead and zinc grades in the low-grade lead-zinc oxide ore is greater than 10%, and the calcium grade is less than 35%; the secondary zinc-containing materials include any two or more of zinc-containing iron slag, zinc-containing sulfuric acid slag, and pyrometallurgical lead slag; the moisture content in the mixed ore is <18%. S2, natural gas and oxygen-enriched air are added into the side-blown smelting furnace, and the mixed ore in S1 is sent into the side-blown smelting furnace. After smelting, high-lead dust and liquid zinc-containing slag are obtained. S3, high-pressure air and pulverized coal are introduced into the fuming furnace A, and the temperature is controlled at 1150-1250℃. The liquid zinc-containing slag in S2 is sent to the fuming furnace A and smelted to obtain zinc oxide dust A. S4 involves mixing high-lead dust from S2 with lead slag, iron slag, and lead concentrate in a mass ratio of 1:1:1:2, then feeding it into a top-blown smelting furnace. Pulverized coal is injected into the furnace, and the temperature is controlled at 950–1050°C. After smelting, molten lead-rich slag is obtained. This molten lead-rich slag is then periodically transported to a side-blown reduction furnace, where oxygen-enriched air and natural gas are introduced, along with lump coal. The temperature is controlled at 1050–1200°C, and reduction smelting yields crude lead and reduction slag. After electrolytic smelting and die casting of the crude lead, lead ingots and silver ingots are obtained. S5, the reducing slag in S4 is periodically fed into the fuming furnace B, and pulverized coal and high-pressure air are introduced into the fuming furnace B to obtain zinc oxide dust B; S6, zinc oxide dust A and zinc oxide dust B are fed into a hydrometallurgical zinc refining system to obtain germanium concentrate, zinc-containing filtrate, iron slag and lead slag. The lead slag and iron slag are returned to S4 for batching. The zinc-containing filtrate is purified and impurities are removed to obtain supernatant and germanium-containing filter residue. The germanium-containing filter residue is calcined to obtain germanium concentrate. The supernatant is purified and electrolytically melted to obtain zinc ingots.

[0024] Based on the above description, an embodiment of the present invention is proposed for a comprehensive recovery method of low-grade lead-zinc oxide ore resources.

[0025] First Embodiment A feasibility test was conducted in this embodiment; Test Procedure S1, low-grade lead-zinc oxide ore, hydrometallurgical zinc leaching residue, iron slag, lump coal, quartz sand, and secondary zinc-containing materials are mixed in a mass ratio of 4:4:2:2:2:1 to obtain a mixed ore; for every 60 tons of mixed ore, 16 tons of low-grade lead-zinc oxide ore, 16 tons of hydrometallurgical zinc leaching residue, 8 tons of iron slag, 8 tons of lump coal, 8 tons of quartz sand, and 4 tons of secondary zinc-containing materials need to be added; the particle size of the low-grade lead-zinc oxide ore is ≤10mm; the sum of lead and zinc grades in the low-grade lead-zinc oxide ore is greater than 10%, and the calcium grade is less than 35%; the secondary zinc-containing materials include any two or more of zinc-containing iron slag, zinc-containing sulfuric acid slag, and pyrometallurgical lead slag; the moisture content in the mixed ore is <18%. S2, the mixture is added to the side-blown smelting furnace at a uniform rate of 27 t / h. Natural gas and oxygen-enriched air are added to the side-blown smelting furnace. The process conditions for smelting low-grade lead-zinc oxide ore in the side-blown smelting furnace are controlled as follows: the pressure of the natural gas is 0.2-0.4 MPa, and the flow rate is 1000-1400 Nm³ / h; the pressure of the oxygen-enriched air is 0.18-0.35 MPa, and the flow rate is 9000-10000 Nm³ / h. 3 / h. Melting temperature 1150~1350℃, oxygen-enriched air concentration 53%; The mixed ore in S1 is fed into a side-blown smelting furnace, with a smelting cycle of 3 hours per furnace. The slag produced during smelting flows through a slag chute to the fuming furnace A. The difference in slag pool depth before and after slag discharge is greater than 0.6 meters. The sulfur dioxide flue gas generated during smelting in the furnace is cooled by a waste heat boiler and collected by an electrostatic precipitator before being sent to the flue gas acid production facility. After smelting, high-lead dust and liquid zinc-containing slag are obtained. The high-lead dust is sent to the lead pyrometallurgical batching process.

[0026] S3 introduces high-pressure air at 24,000 m³ / h and pulverized coal at 4.5 t / h into the A-section of the fuming furnace. It receives secondary air from the side-blown slag furnace with a pressure difference exceeding 10 kPa, controlling the reduction and volatilization temperature at 1150–1250℃. The smelting cycle is 3 hours per furnace, producing zinc oxide dust containing lead, zinc, silver, and germanium, which is supplied to the hydrometallurgical zinc smelting system. The resulting tailings are water-quenched and transported off-site for use in the building materials and cement industries. The liquid zinc-containing slag in S2 is sent to the fuming furnace A, and zinc oxide dust A is obtained after smelting. For reduction smelting in Furnace A, the waste slag composition requirements are: 22-28% iron, 20-24% silicon dioxide, and 12-18% calcium oxide.

[0027] S4 involves mixing high-lead dust from S2 with lead slag, iron slag, and lead concentrate in a mass ratio of 1:1:1:2, and then feeding it into a top-blown smelting furnace. The smelting cycle is 3 hours per furnace. Pulverized coal is injected into the top-blown smelting furnace, and the temperature is controlled at 950–1050℃. After smelting, molten lead-rich slag is obtained. The molten lead-rich slag is then periodically transported to a side-blown reduction furnace. Oxygen-enriched air and natural gas are introduced into the side-blown reduction furnace, and lump coal is added. The temperature is controlled at 1050–1200℃, and reduction smelting yields crude lead and reduction slag. After electrolytic smelting and die casting of the crude lead, lead ingots and silver ingots are obtained. S5, the reducing slag in S4 is periodically fed into the fuming furnace B, and pulverized coal and high-pressure air are introduced into the fuming furnace B to obtain zinc oxide dust B; S6, zinc oxide dust A and zinc oxide dust B are fed into a hydrometallurgical zinc refining system to obtain germanium concentrate, zinc-containing filtrate, iron slag and lead slag. The lead slag and iron slag are returned to S4 for batching. The zinc-containing filtrate is purified and impurities are removed to obtain supernatant and germanium-containing filter residue. The germanium-containing filter residue is calcined to obtain germanium concentrate. The supernatant is purified and electrolytically melted to obtain zinc ingots.

[0028] The material composition is as follows: Table 1. Main chemical components of zinc leaching residue from hydrometallurgical processes (dry basis, %) Ge Ag The unit is g / t Table 2. Main chemical components of low-grade lead-zinc oxide ore (dry basis, %) Ge Ag The unit is g / t The zinc oxide fume wet zinc smelting process is as described in the process flow.

[0029] First comparison Compared with Example 1, the same batch of low-grade lead-zinc oxide ore and hydrometallurgical zinc leaching residue were treated using other processes, and the experimental results are as follows: Table 3 Energy consumption indicators for commonly used processes in processing low-grade lead-zinc oxide ore In summary, as shown in Table 3, the side-blown smelting furnace combined with fuming furnace process of the present invention has a wider range of raw material applicability and a larger mineral processing capacity compared with other smelting processes. The recovery rate of lead is greater than or equal to 98%, the recovery rate of zinc is 88% to 94.5%, the recovery rate of silver is 95% to 98%, the recovery rate of germanium reaches 83%, and cadmium is recycled as sponge cadmium for productization.

[0030] Second pair of proportions Compared with Example 1, all other conditions remained completely unchanged, except for another batch of low-grade lead-zinc oxide ore and hydrometallurgical zinc leaching residue, whose main chemical composition is shown in the table below; The side-blown smelting furnace + fuming furnace process in this application was compared separately with the direct smelting process using a fuming furnace (processing the same batch of low-grade lead-zinc oxide ore and hydrometallurgical zinc leaching residue). The test results are as follows: Table 4. Main chemical components of leaching residue (dry basis, %) Ge Ag The unit is g / t Table 5. Main chemical components of oxide ores (dry basis, %) Ge Ag The unit is g / t During the smelting process, the overall equipment operating conditions, negative pressure, slag melting pool depth, slag type, flue gas volume, temperature, sulfuric acid flue gas SO2 concentration, boiler evaporation rate, and the periodic matching between the side-blown smelting furnace and the upstream and downstream metallurgical furnaces are comprehensively controlled, and the amount of lump coal added and the material feeding rate are adjusted in real time. Natural gas flow rate > 1200 Nm³ / h; oxygen-enriched air concentration > 45%, oxygen-enriched air flow rate > 8000 Nm³ / h.

[0031] Table 6 Energy consumption indicators for commonly used processes in processing low-grade lead-zinc oxide ore In summary, compared with the direct smelting process using a side-blown smelting furnace and a fuming furnace, the side-blown smelting furnace + fuming furnace process has a larger mineral processing capacity and a stronger adaptability to the main metal grades of lead-zinc oxide ores; the recovery rates of lead and zinc are higher, with lead recovery rates greater than or equal to 98%, zinc recovery rates of 88% to 94.5%, silver recovery rates of 95% to 98%, and germanium recovery rates of 83%.

[0032] It should be noted that although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the present invention.

[0033] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for comprehensive recovery of low-grade lead-zinc oxide ore resources, characterized in that, The method comprises the following steps: S1, low-grade lead-zinc oxide ore, zinc hydrometallurgy leaching residue, iron slag, lump coal, quartz sand and secondary zinc-containing materials are proportioned according to the mass ratio of 4:4:2:2:2:1 to obtain mixed ore; The sum of the lead-zinc grade in the low-grade lead-zinc oxide ore is greater than 10%, and the calcium grade is less than 35%; The secondary zinc-containing materials include any two or more of zinc-containing iron slag, zinc-containing sulfuric acid slag and lead pyrometallurgy slag; S2, the mixed ore in S1 is sent into a side-blown smelting furnace to obtain high-lead fumes and liquid zinc-containing slag; S3, the liquid zinc-containing slag in S2 is sent to a fuming furnace A, and zinc oxide fumes A are obtained after smelting; S4, the high-lead fumes in S2 are proportioned with lead slag, iron slag and lead concentrate according to the mass ratio of 1:1:1:2, and then sent into a top-blown smelting furnace to obtain molten lead-rich slag, and the molten lead-rich slag is periodically sent to a side-blown reduction furnace to obtain crude lead and reduction furnace slag; After the crude lead is electrolytic smelting and die-casting, lead ingots and silver ingots are obtained; S5, the reduction furnace slag in S4 is periodically sent into a fuming furnace B to obtain zinc oxide fumes B; S6, the zinc oxide fumes A and the zinc oxide fumes B are sent into a zinc hydrometallurgy system to obtain germanium concentrate, zinc-containing filtrate, iron slag and lead slag, the lead slag and the iron slag are returned to S4 for proportioning, and the zinc-containing filtrate is purified and impurity-removed to obtain supernatant and germanium-containing filter residue; The germanium concentrate is obtained after the germanium-containing filter residue is calcined; The zinc ingot is obtained after the supernatant is purified and electrolytic cast.

2. The method of claim 1, wherein, The mass ratio of FeO to SiO2 in the mixed ore is (1.3-1.5):1, and the mass ratio of CaO to SiO2 is (0.5-0.8):

1.

3. The method of claim 1, wherein, In S3, high-pressure air 24000m³ / h and 4.5t / h of pulverized coal are fed into the fuming furnace A, the temperature in the furnace is 1150-1250℃, and the smelting period is 3 hours / furnace.

4. The method of claim 1, wherein, In S4, pulverized coal is sprayed into the top-blown smelting furnace, the temperature is controlled at 950-1050℃, the delivery period of the molten lead-rich slag is 2.5-3.5 hours, and the temperature in the side-blown reduction furnace is 1050-1200℃.

5. The method of claim 1, wherein, In S5, pulverized coal and high-pressure air are fed into the fuming furnace B, the smelting temperature is 1100-1250℃, and the smelting period is 1.5-3h / furnace.

6. The method according to any one of claims 3 to 5, characterized in that, The pulverized coal heat value is 4000-6500 kcal·kg -1 The pulverized coal fixed carbon content is > 50%, S content is < 2.5%, volatile matter content is 10%-25%, water content is < 2%, ash content is < 30%, and particle size < 200 mesh accounts for > 70% of the total pulverized coal volume.

7. The method of any one of claims 3-5, wherein, The pulverized coal supply system is a Ruedek pulverized coal injection system, and the given amount of pulverized coal is 2-5.5t / h.

8. The method of claim 1, wherein, In S1, the particle size of the low-grade lead-zinc oxide ore is ≤10mm, the moisture content of the secondary zinc-containing materials is 10%-18%, and the moisture content of the mixed ore is <18%.

9. The method of claim 1, wherein, In S2, the smelting temperature of the side-blown smelting furnace is 1150-1350℃, and the smelting period is 2-4h / furnace.

10. The method of claim 1, wherein, Smelting discard slag is generated in the fuming furnace A and the fuming furnace B, and the water-quenched slag is obtained after the smelting discard slag is water-quenched, and the water-quenched slag is recycled as a cement building material raw material.

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