Process for efficiently recovering tin, copper and silver in kesterite based on sulfur potential and oxygen potential regulation and control method

Abstract

The invention discloses a process for efficiently recovering tin, copper and silver in kesterite based on a sulfur potential and oxygen potential regulation and control method. The process comprises the following steps that the kesterite, a vulcanizing agent, a reducing agent and a solvent are mixed and granulated; the obtained materials are subjected to volatilization smelting, and tin-containing smoke dust, copper matte and furnace slag are obtained; during smelting, the sulfur potential of a system is controlled to be log pSO2 = 1.0 + / -0.5, and the oxygen potential of the system is controlled to be log pO2 =-7 + / -0.5; mixing the obtained tin-containing smoke dust with a reducing agent and a solvent, and carrying out reduction smelting; and then a reducing agent is supplemented, the temperature is increased, zinc evaporation smelting is conducted, and crude tin, secondary smoke dust and furnace slag are obtained. The technology is good in adaptability, the tin-copper-silver bulk concentrate can be directly treated, low-grade raw materials which are difficult to treat through a traditional technology can be effectively utilized, efficient recycling of valuable metal such as tin, copper, silver and zinc is achieved, and the content of the valuable metal in slag is low.

Description

Technical Field

[0001] This invention belongs to the field of pyrometallurgical technology, specifically relating to a combined process for efficiently separating and recovering tin, copper, and silver from tin ore. Background Technology

[0002] Tin, copper, and silver are strategic non-ferrous metals in high demand in the electronics and new energy sectors, but the global tin ore reserve-to-production ratio has declined rapidly over the past two decades, highlighting the problem of resource scarcity.

[0003] The Mugistun region of Tajikistan is rich in tin ore, and developing this deposit could alleviate the current market shortage of tin and copper resources. Tin ore is a typical tin-copper symbiotic sulfide deposit, with tin and copper exhibiting similar chemical properties, making separation particularly challenging.

[0004] Existing patents such as CN105886783A, CN103060571A, and CN105886783B primarily focus on secondary resources or materials, where tin typically exists in a free state as SnO2 or SnO. However, stud ore is a primary sulfide mineral, where tin is embedded in the mineral structure in a lattice-enclosed state of Cu2FeSnS4. This tin occurrence form, which is drastically different from that of secondary resources, makes the aforementioned existing technologies significantly less suitable for stud ore.

[0005] The tin smelting process disclosed in CN113667836A achieves the recovery of valuable metals by combining fuming furnace blowing with matte enrichment, but the process has obvious limitations: first, the zinc recovery rate is low, making it difficult to efficiently utilize the zinc resources associated with tin ore; second, a large amount of sulfur concentrate needs to be added in batches, making the operation process cumbersome and not conducive to continuous industrial production.

[0006] The bottom-blown furnace process developed by the authorized patent CN102925702B can be used to process copper, zinc, tin and lead in slag and low-grade tin ore. However, the process adopts a staged volatilization mode for lead, zinc and tin. The multi-stage temperature and atmosphere control not only increases the complexity of operation, but also increases energy consumption and production cycle. It is also difficult to meet the high-efficiency processing requirements of tin ore.

[0007] Traditional pyrometallurgical tin refining processes rely solely on slag formation, making it difficult to achieve directional separation of tin into the metallic phase and copper and silver into the matte phase, resulting in low recovery rates of valuable metals. While hydrometallurgical processes can process some copper-tin ores, they require high-grade raw materials and consume a huge amount of sulfuric acid. However, the mining areas in Tajikistan are located in remote mountainous regions, making the procurement and transportation of sulfuric acid expensive and difficult to apply on a large scale.

[0008] In summary, there is an urgent need to develop a highly efficient pyrometallurgical process that is adaptable to raw materials, has a simple process, controllable auxiliary material usage, low equipment maintenance difficulty, and is suitable for remote mining areas. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the background art above, and to provide a process for efficient recovery of tin, copper and silver from tin ore based on sulfur potential and oxygen potential regulation.

[0010] To solve the above-mentioned technical problems, the technical solution proposed by this invention is as follows:

[0011] A process for efficiently recovering tin, copper, and silver from stent ore based on sulfur potential and oxygen potential regulation includes the following steps: (1) Mix tin ore with sulfiding agent, reducing agent and solvent and granulate; (2) The material obtained in step (1) is volatilized and smelted to obtain tin-containing dust, copper matte and slag; the sulfur potential of the system is controlled at log pSO2=1.0±0.5 and the oxygen potential is controlled at log pO2=-7±0.5 during smelting. (3) The tin-containing dust obtained in step (2) is mixed with reducing agent and solvent and then reduced and smelted; then the reducing agent is added and the temperature is raised to carry out zinc smelting to obtain crude tin, secondary dust and slag.

[0012] As a further improvement, the sulfiding agent in step (1) is one or more of pyrite, sulfur, pyrite, calcium sulfide, calcium sulfate, and sodium sulfide.

[0013] As a further improvement, the sulfiding agent in step (1) is calcium sulfate and pyrite.

[0014] As a further improvement, the amount of pyrite and calcium sulfate added to the sulfiding agent in step (1) is 25-30% and 15-20% of the mass of tin ore, respectively.

[0015] As a further improvement, the reducing agent in step (1) is coke, and the amount added is 1.2 to 1.5% of the mass of tin ore.

[0016] As a further improvement, the temperature of the volatilization melting in step (2) is 1320~1380℃.

[0017] As a further improvement, the excess air coefficient during the volatilization smelting process in step (2) is maintained at 0.65~0.75.

[0018] As a further improvement, the reduction smelting temperature in step (3) is 1150~1250℃, and the zinc steaming smelting temperature is 1300~1400℃.

[0019] As a further improvement, the reducing agent in step (3) is coke, and the amount of reducing agent added twice is 12-18% and 3-8% of the mass of tin-containing dust.

[0020] As a further improvement, the solvent is quartz or lime.

[0021] This invention achieves efficient separation of tin, copper, and silver through a process combining "granulation pretreatment + precise sulfur and oxygen potential controlled electric furnace volatilization smelting + segmented heating and dust reduction," taking into account the sulfide characteristics of stentrite. Specifically, the core innovation of this invention lies in the discovery of a sulfur-oxygen potential coupling control window adapted to the lattice characteristics of stentrite through precise thermodynamic design, fundamentally solving the separation problem caused by the coexistence of tin, copper, and silver lattices. The specific thermodynamic design principle is as follows: ① High efficiency in tin volatilization (the stable phase is gaseous SnS, not Sn, SnO or SnO2); ② Copper-silver oriented matte (the stable copper phase is Cu2S, not Cu, CuO, or Cu2O); ③ Efficient slag formation for impurities such as iron and silicon (the stable phase of iron is FeS or FeO, which is beneficial for reaction with SiO2). The thermodynamic dominance phase diagrams of the Sn-OS, Fe-OS, and Cu-OS systems at 1350℃ were simulated using the HSC6.0 software system. Figure 2 , 3 4) The first identification of the unique intersection window where the above three target phase regions coexist: log pSO2 = 1.0 ± 0.5, log pO2 = 7±0.5. The non-obviousness of this window lies in the fact that deviation from either end (too high / too low sulfur potential, too high / too low oxygen potential) will lead to phase disorder (such as the formation of non-target phases like SnO2, SnS2, Cu-Sn alloys, etc.), making separation impossible. This thermodynamic discovery constitutes the core theoretical basis of the process of this invention and is also a substantial feature that distinguishes it from existing empirical smelting technologies.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This process has good adaptability. It can directly process tin-copper-silver mixed concentrate, effectively utilize low-grade raw materials that are difficult to process with traditional processes, alleviate the industry pressure of high-quality tin ore resource shortage, and conform to the development trend of comprehensive resource utilization.

[0023] 2. Based on the sulfide-affinity of tin, copper, and silver and the oxy-affinity of impurities such as iron, magnesium, calcium, and silicon in the ore phase, as well as the differences in vapor pressure and density of tin sulfide and other substances, the tin-copper-silver ore phase can be directionally transformed by adding a sulfiding agent to the tin-copper-sulfur polymetallic concentrate to adjust the sulfur potential and oxygen potential during smelting, thus realizing a short-process smelting of tin-copper-silver polymetallic ores.

[0024] 3. Significant synergistic effects of reagents: Calcium sulfate, pyrite, calcium sulfide and other substances form a synergistic sulfidation system, which effectively solves the problem of sulfur potential drift caused by uneven sulfur release rate of single sulfiding agents, and achieves precise and stable control of sulfur potential window; the decomposition products of calcium sulfate synergistically form slag with quartz and iron oxides, reduce slag melting point and viscosity, synergistically enhance the separation of valuable metals from slag phase, and reduce copper and silver entrainment losses.

[0025] 4. The process steps are simple, key parameters are easy to monitor and adjust, no complicated and delicate operations are required, it is suitable for large-scale industrial production, reduces operation and maintenance difficulty and labor costs, and achieves efficient recovery of valuable metals such as tin, copper, silver and zinc, with low content of valuable metals in the slag. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the process flow of the present invention; Figure 2 The thermodynamic dominance phase diagram for the Sn-OS system (1350℃); Figure 3 The thermodynamic dominance phase diagram for the Fe-OS system (1350℃); Figure 4 The thermodynamic dominance phase diagram for the Cu-OS system (1350℃). Detailed Implementation

[0028] To facilitate understanding of the present invention, the present invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0029] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0030] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0031] In some specific embodiments, the process of the present invention for the efficient recovery of tin, copper, and silver from stentre ore based on sulfur potential and oxygen potential regulation is as follows: Figure 1 It includes the following steps: (1) Mix tin ore with sulfiding agent, reducing agent (e.g., coke) and solvent (e.g., quartz) and granulate.

[0032] This invention controls the sulfur potential of the system to remain stable at log pSO2 = 1.0 ± 0.5 and the oxygen potential to remain stable at log pO2 = -7 ± 0.5 during volatilization smelting. The sulfur and oxygen potentials are related to the amount of vulcanizing agent, the amount of reducing agent, the air intake during volatilization smelting, and the volatilization smelting temperature. These factors can be adjusted using methods known in the art to keep the sulfur and oxygen potentials within the aforementioned ranges.

[0033] In some embodiments, the sulfiding agent can be one or more of pyrite, sulfur, pyrite, calcium sulfide, calcium sulfate, and sodium sulfide. Preferably, calcium sulfate and pyrite are used in a synergistic ratio. Calcium sulfate can act as a sulfur potential buffering synergistic sulfiding agent, forming a fast-release + slow-release sulfur source combination with pyrite (a fast-release sulfur source). This ensures that the sulfur potential reaches the target quickly in the initial stage of smelting, and also continuously replenishes SO2 through the slow decomposition of calcium sulfate in a weak reducing atmosphere, avoiding sulfur potential fluctuations caused by a single sulfiding agent.

[0034] The amount of sulfiding agent can be calculated based on the Sn-OS / Cu-OS / Fe-OS thermodynamic dominance phase diagram at the smelting temperature.

[0035] Preferably, the amounts of pyrite, calcium sulfate, coke, and quartz added are 25-30%, 15-20%, 1.2-1.5%, and 15-25% of the mass of tin ore, respectively.

[0036] In some embodiments, tin ore is mixed with sulfiding agent, coke and quartz in a certain proportion, and then ground to a specified fineness using a ball mill. An appropriate amount of water is added (to control the moisture content), and balls of a fixed diameter are prepared by a bidirectional extrusion baller to improve the compressive strength of the balls. The balls are first dried to a low moisture content in a hot air circulating oven, and then dried again for a short time before entering the furnace to ensure that the moisture in the balls is completely removed and to prevent steam impact during smelting.

[0037] (2) The material from step (1) is volatilized and smelted to obtain tin-containing dust, copper matte and slag.

[0038] In some embodiments, the melting temperature is 1320~1380℃ and the melting time is 3~5h.

[0039] During controlled volatilization smelting, the sulfur potential of the system was stabilized at log pSO2 = 1.0 ± 0.5, and the oxygen potential was stabilized at log pO2 = -7 ± 0.5. Within this sulfur-oxygen potential control window, Sn exists as the easily volatile SnS, Cu forms Cu2S and enters the copper matte phase, and iron exists as Fe. 0.877 In the S phase region, it undergoes a slag-forming reaction with SiO2.

[0040] In some embodiments, the baseline air intake for volatile melting is calculated based on an excess air coefficient (the ratio of actual air consumption to theoretical air consumption) of 0.65 to 0.75 (weak reducing atmosphere). That is, the excess air coefficient is maintained at 0.65 to 0.75.

[0041] This invention, based on the lattice characteristics of tinplate, determines a specific sulfur-oxygen potential control window (log pSO2 = 1.0 ± 0.5, log pO2 = ...). (7±0.5), by adjusting the sulfur potential to generate volatile SnS, efficient volatilization and separation of tin in tin ore is achieved, while Cu2S is generated. Cu and Ag enter the matte phase to avoid alloying loss, and iron enters the slag phase. After smelting, slag, flue dust and copper matte are obtained.

[0042] (3) Mix tin-containing fumes with reducing agent and solvent (e.g., lime or quartz) for reduction smelting, then add reducing agent and heat up for zinc steaming smelting to obtain crude tin, secondary fumes and slag.

[0043] In some embodiments, the amount of reducing agent added twice is 12-18% and 3-8% of the mass of tin-containing dust.

[0044] In some embodiments, reduction smelting is carried out at 1150~1250℃ for 3~5 hours, and zinc vaporization smelting is carried out at 1300~1400℃ for 1.5~2.5 hours.

[0045] In some embodiments, the flue gas is mixed with coke, heated to a first target temperature and held at that temperature to reduce SnO2 in the flue gas to crude tin. The reducing atmosphere is controlled to prevent secondary oxidation of Sn. The temperature is then raised to a second target temperature and held at that temperature, allowing volatile impurities such as Zn to enter the secondary flue gas (the secondary flue gas can be recycled for reduction, improving the overall Sn recovery rate and recovering zinc). After cooling, crude tin, low-tin reduction slag, and flue gas (desulfurized) are obtained, achieving efficient Sn recovery.

[0046] Example 1 (1) Mixing and granulation: Take a certain amount of dry-basis styrene, the composition of which is shown in Table 1, and add 27% pyrite, 18% calcium sulfate, 1.4% coke, and 20% quartz by weight of raw materials. Use a mixer to add deionized water to control the moisture content for granulation, and dry the pellets. The above-mentioned amount of sulfiding agent was calculated based on the Sn-OS / Cu-OS / Fe-OS thermodynamic dominance phase diagram at 1350℃ to ensure that the sulfur potential of the system is stabilized at log pSO2=1.0±0.5 by the decomposition of pyrite and calcium sulfate during smelting, and the oxygen potential is stabilized at log pO2=-7±0.5 by controlling the amount of coke.

[0047] Table 1. Composition of tin ore

[0048] (2) Volatilization smelting: Smelting temperature 1350℃, smelting time 4h, dust collected by cyclone dust collector and bag dust collector. The sulfur potential and oxygen potential of the system were controlled during smelting as follows: log pSO2 = 1.0 ± 0.5, log pO2 = 7±0.5 (excess air coefficient maintained at 0.65~0.75, adjusting intake air volume to maintain oxygen potential). Under this sulfur-oxygen potential control window, Sn exists as volatile SnS, Cu forms Cu2S and enters the copper matte phase, and iron exists as Fe. 0.877 In the S phase region, a slag-forming reaction occurs with SiO2. After smelting, the melt is allowed to cool naturally, and the upper slag layer and the lower copper matte layer are separated by density difference. The measured volatility of Sn was 92%, the Cu matte incorporation rate was 85.43%, and the Ag matte incorporation rate was 85.77%.

[0049] (3) Reduction smelting: The tin-rich flue dust obtained in the previous step is added to 15% coke and 8% CaO and smelted at 1200℃ for 4 hours for tin reduction smelting. After the smelting is completed, 5% coke is added and zinc is steamed and smelted at 1350℃ for 2 hours to obtain crude tin and secondary flue dust. The secondary flue dust (with a Zn volatility of 75.79%, and most of the Zn is enriched in it) and the secondary flue dust containing Sn can be returned to this reduction smelting process for recycling, thereby maximizing the recovery of tin resources. According to the test report data, the total Sn recovery rate of this process reaches 99.15%.

[0050] Comparative Example 1 (1) The same batch of tin ore as in Example 1 was used. The mixing and granulation method was the same as in Example 1. The only difference was that pyrite was not added, but iron oxide with the same "iron molar ratio" as pyrite in Example 1 was added instead. No other sulfur source was used.

[0051] (2) Using the same equipment and process parameters as in Example 1—melting temperature 1350℃, holding time 4h—the same oxygen potential (weak reduction) was maintained by adjusting the air intake. The goal was to convert tin into crude tin through one-step reduction, while allowing copper and silver to enter the copper matte phase, and impurities such as silicon, calcium, magnesium, and iron to enter the slag phase. Due to the low sulfur potential of this system, the dominant phases in the phase diagram are Sn and Fe, respectively. 0.945 O and Cu, so after smelting, the melt will form a viscous "slag-metal mixture" without independent crude tin phase and copper matte phase.

[0052] Analysis revealed a Cu-Sn alloy phase in the mixture; the Sn recovery rate based on slag was <50%, and the Ag incorporation rate could not be statistically determined (no independent matte phase was observed), completely failing to achieve the expected goal of "tin reduction to crude tin, copper and silver incorporation into matte, and impurities in slag." This result confirms that the "lattice encapsulation" of stentrite is the core smelting challenge; insufficient sulfur potential cannot break its lattice, and simple reduction can only form a "slag-metal mixture," making directional separation impossible. Traditional pyrometallurgical reduction smelting is ill-suited for stentrite.

[0053] Comparative Example 2 (1) The same batch of Tajik Mugistun tin-copper concentrate as in Example 1 was used, and the mixing and granulation method was the same as in Example 1. The only difference was that only 0.35% coke was added. This would increase the oxygen potential. The oxygen potential was controlled to log pO2 ≥ by adjusting the air intake. 6.

[0054] (2) The same equipment and process parameters as in Example 1 were used—melting temperature 1350℃ and holding time 4h. Under these conditions, the thermodynamically dominant phases of tin, copper, and iron were SnO2, Cu2S, and Fe3O4, respectively. After melting and cooling, obvious stratification was observed.

[0055] Analysis revealed a copper matte phase in the lower layer of the material, with some tin entering the slag phase. Sn volatilization was <50%, Cu sulfur incorporation was 70.3%, and Ag matte incorporation was 68.9%. The high oxygen potential causes some Cu₂S to convert to CuO, reducing the matte incorporation rates of Cu and Ag. Furthermore, it directly disrupts the directional transformation of Sn, inhibiting SnS formation, and the resulting tin in the slag phase is difficult to recover.

[0056] Comparative Example 3 (1) The same batch of Tajik Mugistun tin-copper concentrate as in Example 1 was used. The mixing and granulation method was the same as in Example 1. The only difference was that 3% coke was added and the air intake was adjusted to control the oxygen potential to log pO2≤-10.

[0057] (2) The same equipment and process parameters as in Example 1 were used—melting temperature 1350℃ and holding time 4h. Under these conditions, the thermodynamically stable forms of tin, copper, and iron were SnS2, CuS, and FeS2, respectively. SnS2 has poor thermal stability, and its decomposition products are easily entrained by the melt and are difficult to volatilize; CuS has insufficient stability and is easily decomposed into free Cu, which poses a potential risk of forming an alloy with Sn; FeS2 is difficult to react with quartz to form slag, which leads to an increase in the viscosity of the system. After the melting was completed and cooled, no obvious stratification was observed.

[0058] Analysis revealed that the melt exhibited a uniform and viscous state, with no distinct coarse tin phase, copper matte phase, or slag phase. Only trace amounts of Cu-Sn alloy phase were detected, with a Sn volatilization rate of 34.7% based on slag. This result indicates that the "easily disordered multimetallic phase state" of tin ore is a core smelting challenge. Excessively low oxygen potential causes the stable phases of Sn, Cu, and Fe to deviate from their target morphology, disrupting the volatilization conditions of tin and hindering the directional enrichment of copper and silver. This highlights the necessity of precise control of the multimetallic phase state through the oxygen potential window in this invention.

[0059] Comparative Example 4 (1) The same batch of Tajik Mugistun tin-copper concentrate as in Example 1 was used. The mixing and granulation method was the same as in Example 1. The only difference was that calcium sulfate was not added, and a certain amount of pyrite was added to maintain the total sulfur content of the system as in Example 1.

[0060] (2) The same equipment and process parameters as in Example 1 were used—melting temperature 1350℃ and holding time 4h. Since there was no calcium sulfate as a sulfur potential buffering synergistic sulfurizing agent, and pyrite was used as a single fast-release sulfur source, the sulfur release was too fast in the early stage, causing the sulfur potential to exceed the target window, and the sulfur source was exhausted in the later stage, causing the sulfur potential to fall below the target window.

[0061] Analysis showed that the Sn volatilization rate was 89.2%, the Cu matte incorporation rate was 75.1%, and the Ag matte incorporation rate was 65.5%, all of which were lower than those in Example 1. This result confirms that the "sulfur potential buffering" and "synergistic slag-forming" functions of calcium sulfate are irreplaceable. Pyrite alone cannot maintain a stable sulfur potential window and cannot optimize slag phase properties. The viscous slag phase leads to entrainment, resulting in a decrease in the directional separation efficiency of polymetallic (Cu, Ag) compounds.

[0062] The comparative examples 1-4 above systematically verified the consequences of deviating from the sulfur-oxygen potential coupling window and process design of this invention from four dimensions: "low sulfur potential," "high oxygen potential," "low oxygen potential," and "single sulfurizing agent." These consequences included either failure to destroy the styrene crystal lattice, phase disorder, or a sharp decrease in separation efficiency. This demonstrates the accuracy, necessity, and non-obviousness of the sulfur-oxygen potential window, synergistic sulfurization system, and process combination determined in this invention. It also proves that the technical solution of this invention is not a simple superposition of existing technologies, but a breakthrough design addressing the core challenges of styrene smelting.

[0063] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention should fall within the protection scope of the present invention.

Claims

1. A process for efficiently recovering tin, copper, and silver from stentre ore based on sulfur potential and oxygen potential regulation, characterized in that, The steps include the following: (1) Mix tin ore with sulfiding agent, reducing agent and solvent and granulate; (2) The material obtained in step (1) is volatilized and smelted to obtain tin-containing dust, copper matte and slag; the sulfur potential of the system is controlled at log pSO2=1.0±0.5 and the oxygen potential is controlled at log pO2=-7±0.5 during smelting. (3) The tin-containing dust obtained in step (2) is mixed with reducing agent and solvent and then reduced and smelted; then the reducing agent is added and the temperature is raised to carry out zinc smelting to obtain crude tin, secondary dust and slag.

2. The process for efficient recovery of tin, copper, and silver from stentrepotassium ore based on sulfur potential and oxygen potential regulation according to claim 1, characterized in that, The sulfiding agent in step (1) is one or more of pyrite, sulfur, pyrite, calcium sulfide, calcium sulfate, and sodium sulfide.

3. The process for efficient recovery of tin, copper, and silver from stent ore based on sulfur potential and oxygen potential regulation according to claim 2, characterized in that, The sulfiding agent in step (1) is calcium sulfate and pyrite.

4. The process for efficient recovery of tin, copper, and silver from stentrepotassium ore based on sulfur potential and oxygen potential regulation according to claim 3, characterized in that, In step (1), the amount of pyrite and calcium sulfate added to the sulfiding agent is 25-30% and 15-20% of the mass of tin ore, respectively.

5. The process for efficient recovery of tin, copper, and silver from stentrepotassium ore based on sulfur potential and oxygen potential regulation according to claim 1, characterized in that, The reducing agent in step (1) is coke, and its addition amount is 1.2~1.5% of the mass of tin ore.

6. The process for efficient recovery of tin, copper, and silver from stentrepotassium ore based on sulfur potential and oxygen potential regulation according to claim 1, characterized in that, The temperature of the volatilization smelting in step (2) is 1320~1380℃.

7. The process for efficient recovery of tin, copper, and silver from stentrepotassium ore based on sulfur potential and oxygen potential regulation according to claim 1, characterized in that, In step (2), the excess air coefficient during the volatilization smelting process is maintained at 0.65~0.

75.

8. The process for efficient recovery of tin, copper, and silver from stent ore based on sulfur potential and oxygen potential regulation according to claim 1, characterized in that, The reduction smelting temperature in step (3) is 1150~1250℃, and the zinc steaming smelting temperature is 1300~1400℃.

9. The process for efficient recovery of tin, copper, and silver from stent ore based on sulfur potential and oxygen potential regulation according to claim 1, characterized in that, The reducing agent in step (3) is coke, and the amount of reducing agent added twice is 12-18% and 3-8% of the mass of tin-containing dust.

10. The process for efficient recovery of tin, copper, and silver from stentrepotassium ore based on sulfur potential and oxygen potential regulation according to claim 1, characterized in that, The solvent is quartz or lime.

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