Smelting method of antimony ore

Abstract

The invention discloses a smelting method of antimony ore, and belongs to the technical field of non-ferrous metal smelting. The smelting method provided by the invention comprises the following steps: S1, mixing antimony ore and a smelting aid for granulation, and smelting the obtained particles in an oxygen-containing atmosphere to obtain oxidizing slag; the particulate matter contains the following components in percentage by mass: 18%-30% of Sb, more than or equal to 18% of S, 0.7-1.0% of Fe / SiO2 and 1.0-1.2% of CaO / SiO2; wherein the S occurrence state comprises elemental sulfur or sulfide; the smelting temperature ranges from 1200 DEG C to 1300 DEG C; and S2, reducing the oxidizing slag to obtain crude antimony and reducing slag. According to the smelting method, the low-grade antimony ore can be effectively treated, the recovery rate of antimony is increased, and the mass percentage of antimony in the target product crude antimony is increased.

Description

Technical Field

[0001] This invention relates to the field of non-ferrous metal metallurgy, and in particular to a method for smelting antimony ore. Background Technology

[0002] Antimony is an important strategic metal, widely used in military, electronics, aerospace and other fields. With the continuous development of antimony mining, many operating mines are facing problems such as shortened resource security lifespan and declining ore grades. High-quality single stibnite (Sb2S3) resources are also decreasing. The utilization of complex antimony-bearing resources, such as mixed sulfur-oxygen ores, low-grade sulfide ores, antimony-lead-zinc sulfide ores, and antimony-gold sulfide ores, is becoming increasingly important. In traditional technology, the main processing method for high-quality stibnite is the blast furnace volatilization smelting-reflective furnace reduction smelting process. The blast furnace volatilization smelting method employs unique technical measures such as low charge column, high coke ratio, and high-temperature furnace top. Under a reducing atmosphere, Sb mainly volatilizes into the flue dust to form antimony-oxygen powder. This process has the characteristics of strong raw material adaptability, large processing capacity, and high degree of mechanization, and is currently the widely used antimony ore smelting process. At the same time, this process also has shortcomings: (1) It requires the furnace charge to have an antimony grade of more than 40%, which is particularly suitable for processing high-grade antimony concentrate. Moreover, the higher the antimony grade, the greater the production capacity and the higher the recovery rate; (2) It is not suitable for directly processing powdery materials. The antimony concentrate must be pre-processed into agglomerates through multiple processes such as batching, mixing, rolling, and compaction; (3) It requires a large amount of high-quality metallurgical coke, and the coke ratio is very high, generally 20%~25% of the furnace charge or 30%~45% of the concentrate; (4) The antimony content of the waste slag produced by the blast furnace volatilization smelting is still relatively high, generally reaching about 5%; (5) When processing antimony sulfide ore or sulfur-oxygen mixed ore, a large amount of low-concentration SO2 flue gas will be produced, causing environmental pollution. The nature of the blast furnace volatilization smelting process determines that it has disadvantages such as long process, high energy consumption, low thermal efficiency, high processing cost and difficulty in utilizing low-concentration SO2 flue gas. At present, there is a lack of targeted treatment methods for complex antimony-containing resources, and traditional treatment methods are not effective in treating complex antimony-containing resources.

[0003] Therefore, it is very important to provide a targeted smelting method for processing low-grade antimony ore. Summary of the Invention

[0004] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a smelting method for antimony ore, which can effectively process low-grade antimony ore, improve the antimony recovery rate, and increase the mass percentage of antimony in the target product, crude antimony.

[0005] According to an embodiment of a first aspect of the present invention, a method for smelting antimony ore is provided, the smelting method comprising the following steps: S1. Mix antimony ore and smelting aids to form granules, and then smelt the resulting granules in an oxygen-containing atmosphere to obtain oxide slag. The particulate matter contains the following components by mass percentage: Sb 18%~30%, S ≥ 18%, Fe / SiO2 = 0.7~1.0, CaO / SiO2 = 1.0~1.2; wherein the occurrence state of S includes elemental sulfur or sulfides; The melting temperature is 1200~1300℃; S2. Reduce the oxide slag to obtain crude antimony and reduced slag.

[0006] The mechanism of the smelting reaction is explained as follows: In step S1, In step S1, the reaction that occurs during the smelting includes: 2Sb₂S₃ + ​​9O₂ = 2Sb₂O₃ + 6SO₂; Sb₂S₃ + ​​2Sb₂O₃ = 6Sb + 3SO₂; 4Sb + 3O2 = 2Sb2O3; 2Sb₂O₃ + O₂ = 2Sb₂O₄; 2Sb₂O₄ + O₂ = 2Sb₂O₅.

[0007] The smelting method according to embodiments of the present invention has at least the following beneficial effects: In step S1, by controlling the content of S and its occurrence state, the resulting particulate matter is effectively limited to contain sufficient combustible sulfur, which can burn in an oxygen-containing atmosphere to generate sulfur dioxide and release a large amount of heat at the same time. In step S1, combustible sulfur is fully utilized to replace carbon with sulfur to achieve self-heating smelting. This eliminates the problem of a large amount of low-concentration SO2 waste gas produced during the processing of low-grade antimony ore without the need for coal consumption. The waste heat of the high-concentration SO2 waste gas is then used for acid production.

[0008] In step S1, the antimony oxidation product Sb₂O₃ is highly volatile, which is a key characteristic that allows antimony concentrate to be volatilized using a blast furnace volatilization process to obtain antimony oxide powder. High-valence antimony oxides, on the other hand, are not easily volatilized. This invention, by limiting the oxygen-containing atmosphere, effectively provides a highly oxidizing environment. Adjusting the oxidizing atmosphere causes iron in the oxidizing slag to convert to Fe₂O₃, and antimony readily transforms into high-valence oxides. Simultaneously, under the presence of the strongly alkaline oxide CaO, antimonates are formed, allowing antimony to primarily enter the oxidizing slag and reducing its entry into the oxidizing flue gas as Sb₂O₃.

[0009] In step S1, by controlling the contents of Fe, Si, Ca, and Sb and their relative contents, the oxidized slag can have good fluidity at a temperature of 1200~1300℃. Furthermore, by limiting the content of Sb, the content of the oxidized slag is limited, thus avoiding an increase in slag volume and ultimately reducing energy consumption.

[0010] In step S1, the granulation process can improve the uniformity of raw material mixing; at the same time, it reduces the amount of powder, thus reducing the direct volatilization of easily volatile phases such as Sb2S3 and Sb2O3 into the oxidation waste dust during the oxidation smelting process; that is, granulation inhibits the volatilization of Sb to a certain extent.

[0011] According to some embodiments of the present invention, in step S1, the antimony grade in the antimony ore is ≤40%. That is, the smelting method provided by the present invention is applicable to low-grade antimony ore. The low-grade antimony ore comprises the following components by mass percentage: Sb 20%~40%; for example, it can be 20%, 25%, 28%, 30%, 34%, 35%, 40%; or a range of values ​​composed of any two of the above points; Fe 5%~25%; for example, it can be 5%, 10%, 15%, 18%, 20%, 25%; or a range of values ​​consisting of any two of the above points.

[0012] SiO2 5%~30%; for example, it can be 5%, 10%, 15%, 20%, 24%, 25%, 30%; the range of values ​​formed by any two of the above points.

[0013] CaO 2%~5%; for example, it can be 2%, 2.2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%; the range of values ​​formed by any two of the above points.

[0014] S5%~30%; for example, it can be 5%, 10%, 15%, 16%, 20%, 25%, 30%; the range of values ​​formed by any two of the above points.

[0015] However, it should be noted that the smelting method provided by this invention can be used to process antimony ore of all grades. However, there are already mature commercial processes for processing high-grade antimony ore, so this is not emphasized here.

[0016] According to some embodiments of the present invention, in step S1, the antimony ore includes at least one of antimony sulfide ore (the main antimony phase Sb2S3) and antimony sulfide mixed ore (the main antimony phases Sb2S3, Sb2O3, Sb2O4).

[0017] According to the standard YS / T385-2019, "Antimony Concentrate" classifies antimony concentrate and antimony concentrate with sulfur and oxygen as graded, as shown in Table 1.

[0018] Table 1. Chemical composition of antimony sulfide concentrate and mixed antimony concentrate

[0019] According to some embodiments of the present invention, in step S1, the smelting aid includes zinc oxygen pressure leaching residue.

[0020] Zinc oxygen pressure leaching is a process in the all-hydrometallurgical zinc smelting process. The zinc oxygen pressure leaching residue refers to the residue left after zinc concentrate has undergone oxygen pressure leaching; it is a hazardous waste rich in valuable elements and requires resource-based and harmless disposal. Therefore, the smelting method provided by this invention also utilizes the zinc oxygen pressure leaching residue as a resource, demonstrating good environmental and economic benefits.

[0021] The zinc-oxygen pressure leaching residue comprises the following components by mass percentage: Pb 4%~15%; for example, it can be 4%, 4.3%, 4.5%, 5%, 10%, 15%; the range of values ​​formed by any two of the above points.

[0022] Zn 1%~5%; for example, it can be 1%, 2%, 3%, 4%, 5%; the range of values ​​formed by any two of the above points.

[0023] S35%~60%; for example, it can be 35%, 40%, 45%, 50%, 55%, 60%; the range of values ​​formed by any two of the above points.

[0024] Fe 5%~15%; for example, it can be 5%, 8%, 10%, 11%, 15%; the range of values ​​formed by any two of the above points.

[0025] SiO2 5%~10%. For example, it can be 5%, 6%, 7%, 8%, 9%, 10%; or any two of the above values ​​forming a range.

[0026] The main form of sulfur is elemental sulfur, with a small portion existing as sulfate.

[0027] According to some embodiments of the present invention, the zinc oxygen pressure leaching residue also contains non-metallic elements such as O combined with Pb and Zn.

[0028] According to some embodiments of the present invention, the zinc oxygen pressure leaching residue also contains metallic elements such as Cu, Sb, Bi, and Ag.

[0029] Since the above-mentioned metal elements have low content, are diverse in type, and have little impact on the smelting method provided by the present invention, their content has not been listed for the time being.

[0030] In actual production, if there is no requirement for the harmless treatment of zinc oxygen pressure leaching residue, the zinc oxygen pressure leaching residue can be replaced with a combination of pyrite, limestone, etc. As long as the composition requirements of the particulate matter are met, the technical solution provided by this invention can be effectively implemented.

[0031] According to some embodiments of the present invention, in step S1, the smelting aid comprises pyrite. This allows the utilization of the combustible sulfur and Fe contained therein.

[0032] According to some embodiments of the present invention, in step S1, the raw materials for the mixed granulation further include a flux. The function of the flux includes adjusting the composition of the particles.

[0033] According to some embodiments of the present invention, in step S1, the particle size of the particulate matter is 10 mm to 25 mm. Specifically, it can be a range of values ​​consisting of any two of the above points: 10 mm, 12 mm, 15 mm, 17 mm, 18 mm, 20 mm, 22 mm, or 25 mm. The particulate matter has a spherical morphology.

[0034] According to some embodiments of the present invention, in step S1, the particulate matter contains the following components: Sb = 18%~30%; for example, it can be 18%, 20%, 22%, 24%, 26%, 30%; the range of values ​​formed by any two of the above points; S ≥ 18%; specifically, it can be 18%, 18.01%, 18.02%, 18.03%, 18.05%, 18.1%, 18.3%, 18.5%, 18.7%, 19%, 20%, 21%; or any range of two of the above values. Within this range, overheating caused by excessive heat release from S oxidation can be avoided; it also ensures sufficient sulfur for the autothermal reaction.

[0035] Fe / SiO2 = 0.7~1.0; for example, it can be 0.7, 0.75, 0.8, 0.85, 0.86%, 0.88%, 0.9, 0.95, 1.0; the range of values ​​formed by any two of the above points; CaO / SiO2 = 1.0~1.2; for example, it can be 1, 1.02, 1.05, 1.1, 1.15, 1.2; the range of values ​​formed by any two of the above points.

[0036] In the particulate matter, sulfur exists in the form of elemental sulfur or sulfides. Additionally, sulfur may also exist in small amounts as sulfates.

[0037] According to some embodiments of the present invention, in step S1, the volume percentage of oxygen (externally blown gas) injected by the oxygen lance in the oxygen-containing atmosphere is 85% to 95%. For example, it can be 85%, 88%, 90%, 92%, 94%, 95%; or a range of values ​​composed of any two of the above points.

[0038] According to some embodiments of the present invention, in step S1, the melting temperature is 1200~1300℃. For example, it can be 1200℃, 1220℃, 1240℃, 1250℃, 1260℃, 1280℃, or 1300℃; or any range of any two of the above points.

[0039] According to some embodiments of the present invention, in step S1, the smelting product further includes oxidized waste dust and oxidized waste gas.

[0040] The oxidized waste dust is recycled as a raw material for the mixed granulation; the oxidized waste dust contains antimony trioxide.

[0041] The oxidizing waste gas contains a high concentration of sulfur oxides, which are used for acid production after being purified by waste heat utilization.

[0042] According to some embodiments of the present invention, in step S1, the equipment used for smelting includes an oxidation furnace. In actual production, the oxygen-containing atmosphere is injected through an oxygen lance; the particulate matter is transported into the oxidation furnace via a belt conveyor. The oxidation furnace is a side-blown oxidation furnace.

[0043] According to some embodiments of the present invention, in step S1, the mass of the components in the oxidation slag satisfies the following conditions: Fe2O3 / SiO2 = 1.0~1.4; for example, it can be 1.0, 1.1, 1.2, 1.24%, 1.25, 1.3, 1.4; or a range of values ​​composed of any two of the above points.

[0044] CaO / SiO2 = 1.0~1.2; for example, it can be 1.0, 1.02, 1.05, 1.1, 1.15, 1.2; or a range of values ​​consisting of any two of the above points.

[0045] According to some embodiments of the present invention, in step S2, the reduction includes adding a flux and a carbonaceous reducing agent to the hot oxidized slag. One function of the flux is to adjust the composition of the reduced slag, and the carbonaceous reducing agent serves to heat and reduce.

[0046] According to some embodiments of the present invention, the carbonaceous reducing agent comprises pulverized coal.

[0047] According to some embodiments of the present invention, in step S2, the pulverized coal accounts for 15% to 20% of the mass percentage of the mixture used for reduction. Specifically, it can be 15%, 16%, 17%, 18%, 19%, or 20%; or a range of any two of the above values. That is, the smelting method provided by the present invention uses only a small amount of pulverized coal in step S2, and this smelting method significantly saves energy and reduces consumption.

[0048] According to some embodiments of the present invention, in step S2, the reduction temperature is 1200~1300℃. For example, it can be 1200℃, 1220℃, 1240℃, 1250℃, 1260℃, 1280℃, or 1300℃; or any range of any two of the above points.

[0049] According to some embodiments of the present invention, in step S2, the atmosphere of the reduction process includes carbon monoxide, wherein the volume percentage of carbon monoxide is 3-8%. Specifically, it can be 3%, 4%, 5%, 6%, 7%, 8%; or a range consisting of any two of the above values. In actual production, the carbon monoxide is a reaction product of the carbonaceous reducing agent; its volume fraction is controlled by controlling the ratio of the injected gas to the carbonaceous reducing agent.

[0050] According to some embodiments of the present invention, in step S2, during the reduction process, gas is blown in from the outside. The volume percentage of oxygen in the blown gas is 30-55%. Specifically, it can be 30%, 35%, 40%, 45%, 48%, 50%, 55%; or a range of any two of the above values. Using oxygen-enriched air can reduce the volume of reduction waste gas, further reducing the heat carried away by the reduction waste gas, thus achieving energy conservation and emission reduction. According to some embodiments of the present invention, in step S2, the reduction is carried out in a side-blown reduction furnace. In actual production, the gas and pulverized coal are blown into the reduction furnace through a side-blown spray gun.

[0051] According to some embodiments of the present invention, the mass percentage of antimony in the crude antimony is ≥90%. Specifically, it can be 90%, 90.5%, 91%, 91.5%, 92%, 92.5%, or 93%; or a range of any two of the above values. The crude antimony contains impurities such as copper and lead. In actual production, the crude antimony can be further refined using pyrometallurgical methods to obtain refined antimony.

[0052] According to some embodiments of the present invention, in step S2, the reduction products further include reduction waste dust and reduction waste gas; the reduction waste dust is recycled as a raw material for the mixed granulation. The reduction waste dust includes antimony trioxide and lead oxide; in actual production, the reduction waste dust may also contain other components.

[0053] The recycling of the oxidation and reduction waste dust significantly improves the antimony yield in the smelting method.

[0054] According to some embodiments of the present invention, in step S2, the reduction product further includes reducing slag.

[0055] In actual production, hot reducing slag can be water-quenched to obtain water-quenched slag. This water-quenched slag can undergo vitrification, thus rendering the slag harmless.

[0056] In the entire smelting process described above, among the components discharged from the system, apart from the crude antimony, only the water-quenched slag contains antimony, meaning the water-quenched slag represents the antimony loss gap. The antimony mass percentage in the water-quenched slag (reduction slag) is <0.5%. For example, it can be 0.49%, 0.4%, 0.3%, 0.25%, 0.2%, 0.15%, 0.1%; or a range of any two of the above values. Therefore, it can be seen that the smelting method provided by this invention has a high overall antimony recovery rate.

[0057] According to some embodiments of the present invention, the composition of the water-quenched slag, by mass, satisfies the following conditions: FeO / SiO2 = 0.8~1.4; for example, it can be 0.8, 1.0, 1.1, 1.2, 1.4; or a range of values ​​consisting of any two of the above points.

[0058] The CaO / SiO2 ratio is 0.65 to 0.8; specifically, it can be 0.65, 0.7, 0.75, or 0.8; or a range of values ​​consisting of any two of the above points.

[0059] According to some embodiments of the present invention, the flux used in the smelting and reduction processes is independently selected from at least one of limestone, iron ore, and silica.

[0060] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. Attached Figure Description

[0061] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a flowchart of Embodiment 1 of the present invention. Detailed Implementation

[0062] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

[0063] Example 1 This example provides a method for smelting antimony ore, with the specific steps as follows: S1. By mass percentage, the composition of the antimony ore used in this example includes: Sb 34.50%; Fe 16.96%; SiO2 23.00%; CaO 2.10%; S 15.03%; Pb 0.11%; As 0.15%.

[0064] The main components of the zinc oxygen pressure leaching residue used in this example, by mass percentage, include: Pb 4.51%; Zn 4.53%; S 50.06%; Fe 10.07%; SiO 25.80%; and also elements such as O, Cu, Sb, Bi, and Ag. The content of the metal elements is too low to have any impact on the effect in this example.

[0065] Antimony ore, zinc oxygen pressure leaching residue, limestone (flux), and oxidation or reduction waste dust (if any) are mixed and granulated to form spherical particles with an average particle size of 15 mm.

[0066] The amount of each raw material added needs to be controlled so that the particulate matter meets the following requirements: Sb 24.35%; Fe / SiO2=0.85; CaO / SiO2=1.00; S 18.03%.

[0067] The granulated particles obtained from granulation are continuously fed into an oxygen-enriched side-blown oxidizer via a conveyor belt. A 94% oxygen concentration is introduced, and the side-blown furnace's molten pool is controlled to undergo self-heating smelting (the oxidation of elemental sulfur and sulfides releases a large amount of heat, meeting the furnace's heat balance requirements, eliminating the need for additional carbonaceous fuels or other heating). This process yields oxidation waste gas, oxidation dust, and oxidation slag. The melting temperature is approximately 1250°C; Oxidized slag is released intermittently every 20 to 30 minutes; fluctuations within the above time range have almost no impact on the implementation effect of the technical solution in this example.

[0068] The main component of the oxidized slag is antimonate, of which antimony accounts for about 88 wt% of the antimony in the mixture. By mass, the ratio of Fe2O3 / SiO2 in the oxidized slag is 1.21, CaO / SiO2 is 1.00, and Sb is 30.65%. After the oxidized slag reaches a certain height, it is subjected to intermittent slag discharge treatment. Part of the oxidized slag is sent to the oxygen-enriched side-blown reduction furnace for reduction through a chute (step S2). Oxidation waste gas is purified and then used to produce acid through waste heat utilization; Oxidized waste dust contains a certain amount of volatile Sb2O3; oxidized waste dust remixing and granulation process.

[0069] S2. The oxidation slag from reduction step S1 yields crude antimony, reduced slag, reduced waste gas, and reduced waste dust; apart from the oxidation slag, the raw materials contain oxygen-enriched gas, pulverized coal, and flux; among which, The reaction is carried out in a side-blown reduction furnace; The reducing slag is released intermittently every 90 minutes.

[0070] During the reaction, oxygen-enriched gas and pulverized coal are injected through the side-blown furnace lance. The oxygen volume concentration in the oxygen-enriched gas is 50%. The injection rates of oxygen-enriched gas and pulverized coal are controlled to maintain the molten pool temperature at 1250℃, the coal ratio at 18.0%, and the CO volume fraction in the atmosphere inside the reduction furnace at 6%. By adding silica and iron ore (flux), the FeO / SiO2 ratio in the reducing slag is adjusted to 1.0 and the CaO / SiO2 ratio to 0.8.

[0071] During the reduction process, antimony is mainly reduced into crude antimony. After accumulating to a certain amount, it is released through a siphon. The crude antimony obtained has an Sb mass percentage of 91.74%. The crude antimony can then be sent to pyrometallurgical refining to remove impurities such as copper and lead. In the oxidation slag (raw material of the reduction step), about 27.5% of the antimony volatilizes and is oxidized to antimony trioxide and enters the reduction waste dust. The subsequent reduction waste dust is returned to the mixing and granulation step; (i.e., in the reduction process, 27.5% of the Sb in the reactants volatilizes into the reduction flue dust).

[0072] The mass percentage of Sb in the reducing slag is 0.23%. After water quenching, water-quenched slag is obtained, which can achieve slag vitrification. The Sb lost in the water-quenched slag accounts for 0.43% of the material fed into the furnace. Therefore, the comprehensive recovery rate of Sb can reach 99.57%.

[0073] In this example, the component content was obtained by ICP-OES testing; the oxidized slag, reduced slag, and crude antimony were sampled at the discharge port during material discharge, the oxidized waste dust and reduced waste dust were sampled from the outlet of the dust collection equipment, and the other samples were obtained by cone quartering method.

[0074] Example 2 This example provides a method for smelting antimony ore, with the specific steps as follows: S1. By mass percentage, the composition of the antimony ore used in this example includes: Sb 28.55%, Fe 19.38%, SiO2 24.15%, CaO 2.46%, S 16.13%, Pb 0.13%, As 0.21%; The zinc oxygen pressure leaching residue used in this example, by mass percentage, contains: Pb 4.25%, Zn 3.86%, S 55.01%, Fe 6.69%, SiO 26.64%; it also contains elements such as O, Cu, Sb, Bi, and Ag. The content of the metal elements is too low to have any impact on the effect in this example.

[0075] Antimony ore, zinc oxygen pressure leaching residue, limestone (flux), and oxidation or reduction waste dust (if any) are mixed and granulated to form spherical particles with an average particle size of 18 mm.

[0076] The amount of each raw material added needs to be controlled so that the particulate matter meets the following requirements: Sb 20.20%, Fe / SiO2=0.88, CaO / SiO2=1.05, S 18.50%.

[0077] The granulated particles obtained from granulation are continuously fed into an oxygen-enriched side-blown oxidation furnace via a conveyor belt. A 94% oxygen concentration is introduced, and the furnace's molten pool is controlled for autothermal smelting, yielding oxidation waste gas, oxidation dust, and oxidation slag. The melting temperature is approximately 1280℃; Oxidized slag is released intermittently every 20 to 30 minutes; fluctuations within the above time range have almost no impact on the implementation effect of the technical solution in this example.

[0078] The main component of the oxidized slag is antimonate. By mass, the ratio of Fe2O3 / SiO2 in the oxidized slag is 1.26, the ratio of CaO / SiO2 is 1.05, and the content of Sb is 25.55%. After the oxidized slag reaches a certain height, it is subjected to intermittent slag discharge treatment. Part of the oxidized slag is sent to the oxygen-enriched side-blown reduction furnace for reduction through a chute (step S2). Oxidation waste gas is purified and then used to produce acid through waste heat utilization; Oxidized waste dust contains a certain amount of volatile Sb2O3; oxidized waste dust remixing and granulation process.

[0079] S2. The oxidation slag from reduction step S1 yields crude antimony, reduced slag, reduced waste gas, and reduced waste dust; apart from the oxidation slag, the raw materials contain oxygen-enriched gas, pulverized coal, and flux; among which, The reaction is carried out in a side-blown reduction furnace; The reducing slag is released intermittently every 90 minutes.

[0080] During the reaction, oxygen-enriched gas and pulverized coal are blown in through the side-blown furnace lance. The oxygen volume concentration in the oxygen-enriched gas is 45%. The amount of oxygen-enriched gas and pulverized coal injected is controlled to maintain the molten pool temperature at 1280℃, the coal ratio at 16.7%, and the CO volume fraction in the atmosphere inside the reduction furnace at 8%. By adding silica and iron ore (flux), the FeO / SiO2 ratio in the reducing slag is adjusted to 1.1 and the CaO / SiO2 ratio to 0.8.

[0081] During the reduction process, antimony is mainly reduced into crude antimony. After accumulating to a certain amount, it is released through a siphon. The crude antimony obtained has a Sb mass percentage of 90.82%. The crude antimony can then be sent for pyrometallurgical refining to remove impurities such as copper and lead. Some antimony volatilizes and is oxidized to antimony trioxide, which enters the reduction waste dust. The reduction waste dust is then returned to the mixing and granulation step. The mass percentage of Sb in the reducing slag is 0.32%. After water quenching, water-quenched slag is obtained, which can achieve slag vitrification. The Sb lost in the water-quenched slag accounts for 0.88% of the material fed into the furnace. Therefore, the comprehensive recovery rate of Sb can reach 99.12%.

[0082] Comparative Example 1 This example provides a method for smelting antimony ore, with the specific steps as follows: S1. By mass percentage, the composition of the antimony ore used in this example includes: Sb 22.38%, Fe 20.48%, SiO 26.15%, CaO 2.78%, S 14.85%, Pb 0.10%, As 0.20%.

[0083] The zinc oxygen pressure leaching residue used in this example, by mass percentage, contains: Pb 6.15%, Zn 4.23%, S 58.71%, Fe 7.95%, and SiO 25.69%; it also contains elements such as O, Cu, Sb, Bi, and Ag, but the content of these metal elements is too low to have any effect on the results in this example.

[0084] Antimony ore, zinc oxygen pressure leaching residue, limestone (flux), and oxidation or reduction waste dust (if any) are mixed and granulated to form spherical particles with an average particle size of 18 mm.

[0085] The amount of each raw material added needs to be controlled so that the particulate matter meets the following requirements: Sb 16.36%, Fe / SiO2=0.88, CaO / SiO2=1.00, S 18.20%.

[0086] The granulated particles obtained from granulation are continuously fed into an oxygen-enriched side-blown oxidation furnace via a conveyor belt. A 94% oxygen concentration is introduced, and the furnace's molten pool is controlled for autothermal smelting, yielding oxidation waste gas, oxidation dust, and oxidation slag. The melting temperature is approximately 1250°C; Oxidized slag is released intermittently every 20 to 30 minutes; fluctuations within the above time range have almost no impact on the implementation effect of the technical solution in this example.

[0087] The main component of the oxidized slag is antimonate. By mass, the ratio of Fe2O3 / SiO2 in the oxidized slag is 1.26, the ratio of CaO / SiO2 is 1.00, and the content of Sb is 20.76%. After the oxidized slag reaches a certain height, it is subjected to intermittent slag discharge treatment. Part of the oxidized slag is sent to the oxygen-enriched side-blown reduction furnace for reduction through a chute (step S2). Oxidation waste gas is purified and then used to produce acid through waste heat utilization; Oxidized waste dust contains a certain amount of volatile Sb2O3; oxidized waste dust remixing and granulation process.

[0088] S2. The oxidation slag from reduction step S1 yields crude antimony, reduced slag, reduced waste gas, and reduced waste dust; apart from the oxidation slag, the raw materials contain oxygen-enriched gas, pulverized coal, and flux; among which, The reaction is carried out in a side-blown reduction furnace; The reducing slag is released intermittently every 90 minutes.

[0089] During the reaction, oxygen-enriched gas and pulverized coal are blown in through the side-blown furnace lance. The oxygen volume concentration in the oxygen-enriched gas is 45%. The amount of oxygen-enriched gas and pulverized coal injected is controlled to maintain the molten pool temperature at 1250℃, the coal ratio at 15.7%, and the CO volume fraction in the atmosphere inside the reduction furnace at 7%. By adding silica and iron ore (flux), the FeO / SiO2 ratio in the reducing slag is adjusted to 1.1 and the CaO / SiO2 ratio to 0.8.

[0090] During the reduction process, antimony is mainly reduced into crude antimony. After accumulating to a certain amount, it is released through a siphon. The crude antimony obtained has an Sb mass percentage of 86.83%. The crude antimony can then be sent to pyrometallurgical refining to remove impurities such as copper and lead. Some antimony volatilizes and is oxidized to antimony trioxide, which enters the reduction waste dust. The reduction waste dust is then returned to the mixing and granulation step. The mass percentage of Sb in the reducing slag is 0.31%. After water quenching, water-quenched slag is obtained, which can achieve slag vitrification. The Sb lost in the water-quenched slag accounts for 1.06% of the material fed into the furnace. Therefore, the comprehensive recovery rate of Sb can reach 98.94%.

[0091] Comparative Example 2 S1. By mass percentage, the composition of the antimony ore used in this example includes: Sb 34.50%; Fe 16.96%; SiO2 23.00%; CaO 2.10%; S 15.03%; Pb 0.11%; As 0.15%.

[0092] The main components of the zinc oxygen pressure leaching residue used in this example, by mass percentage, include: Pb 4.51%; Zn 4.53%; S 50.06%; Fe 10.07%; SiO 25.80%; and also elements such as O, Cu, Sb, Bi, and Ag. The content of the metal elements is too low to have any impact on the effect in this example.

[0093] Antimony ore, zinc oxygen pressure leaching residue, limestone (flux), pyrite, and oxidation or reduction waste dust (if any) are mixed and granulated to form spherical particles with an average particle size of 15 mm.

[0094] The amount of each raw material added needs to be controlled so that the particulate matter meets the following requirements: Sb 24.22%; Fe / SiO2=1.05; CaO / SiO2=0.90; S 19.10%.

[0095] The granulated particles obtained from granulation are continuously fed into an oxygen-enriched side-blown oxidizer via a conveyor belt. A 94% oxygen concentration is introduced, and the side-blown furnace's molten pool is controlled to undergo self-heating smelting (the oxidation of elemental sulfur and sulfides releases a large amount of heat, meeting the furnace's heat balance requirements, eliminating the need for additional carbonaceous fuels or other heating). This process yields oxidation waste gas, oxidation dust, and oxidation slag. The melting temperature is approximately 1360℃.

[0096] Oxidized slag is released intermittently every 20 to 30 minutes; fluctuations within the above time range have almost no impact on the implementation effect of the technical solution in this example.

[0097] The main component of the oxidized slag is antimonate, of which antimony accounts for about 84 wt% of the antimony in the mixture. By mass, the ratio of Fe2O3 / SiO2 in the oxidized slag is 1.50, CaO / SiO2 is 0.9, and Sb is 29.47%. After the oxidized slag reaches a certain height, it is subjected to intermittent slag discharge treatment. Part of the oxidized slag is sent to the oxygen-enriched side-blown reduction furnace for reduction through a chute (step S2). Oxidation waste gas is purified and then used to produce acid through waste heat utilization; Oxidized waste dust contains a certain amount of volatile Sb2O3; oxidized waste dust remixing and granulation process.

[0098] S2. The oxidation slag from reduction step S1 yields crude antimony, reduced slag, reduced waste gas, and reduced waste dust; apart from the oxidation slag, the raw materials contain oxygen-enriched gas, pulverized coal, and flux; among which, The reaction is carried out in a side-blown reduction furnace; The reducing slag is released intermittently every 90 minutes.

[0099] During the reaction, oxygen-enriched gas and pulverized coal are blown in through the side-blown furnace lance. The oxygen volume concentration in the oxygen-enriched gas is 50%. The amount of oxygen-enriched gas and pulverized coal injected is controlled to maintain the molten pool temperature at 1250℃, the coal ratio at 16.9%, and the CO volume fraction in the atmosphere inside the reduction furnace at 6%. By adding silica and iron ore (flux), the FeO / SiO2 ratio in the reducing slag was adjusted to 1.35 and the CaO / SiO2 ratio to 0.8.

[0100] During the reduction process, antimony is mainly reduced into crude antimony. After accumulating to a certain amount, it is released through a siphon. The crude antimony obtained has a Sb mass percentage of 91.06%. The crude antimony can then be sent to pyrometallurgical refining to remove impurities such as copper and lead. Some antimony volatilizes and is oxidized to antimony trioxide, which enters the reduction waste dust. The reduction waste dust is then returned to the mixing and granulation step. The mass percentage of Sb in the reducing slag is 0.39%. After water quenching, water-quenched slag is obtained, which can achieve slag vitrification. The Sb lost in the water-quenched slag accounts for 0.72% of the material fed into the furnace. Therefore, the comprehensive recovery rate of Sb can reach 99.27%.

[0101] In this example, the component content was obtained by ICP-OES testing; the oxidized slag, reduced slag, and crude antimony were sampled at the discharge port during material discharge, the oxidized waste dust and reduced waste dust were sampled from the outlet of the dust collection equipment, and the other samples were obtained by cone quartering method.

[0102] As can be seen from the above embodiments and comparative examples, the present invention employs an oxygen-enriched enhanced smelting process (step S1) to co-process low-grade antimony ore and zinc-oxygen pressure leaching residue, which can solve the problem of difficult-to-process concentrates with antimony content <40% using the blast furnace volatilization smelting method, and achieve the resource utilization and harmless treatment of zinc-oxygen pressure leaching residue. Simultaneously, within the conditions provided by the present invention, the smelting temperature required in step S1 can be significantly reduced, thus lowering energy consumption. Furthermore, the product obtained by the present invention is crude antimony, and subsequent refining of crude antimony is relatively simple; that is, the smelting method provided by the present invention significantly saves post-processing steps of the product through the selection of smelting aids and the design of the process.

[0103] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A method for smelting antimony ore, characterized in that, The smelting method includes the following steps: S1. Mix antimony ore and smelting aids to form granules, and then smelt the resulting granules in an oxygen-containing atmosphere to obtain oxide slag. The particulate matter contains the following components by mass percentage: Sb 18%~30%, S ≥ 18%, Fe / SiO2 = 0.7~1.0, CaO / SiO2 = 1.0~1.2; wherein the occurrence state of S includes elemental sulfur or sulfides; The melting temperature is 1200~1300℃; S2. Reduce the oxide slag to obtain crude antimony and reduced slag.

2. The smelting method according to claim 1, characterized in that, In step S1, the smelting aid includes zinc oxygen pressure leaching residue; and / or, in step S1, the smelting aid includes pyrite.

3. The smelting method according to claim 1, characterized in that, In step S2, the reduction includes adding flux and carbonaceous reducing agent to the hot oxidized slag.

4. The smelting method according to claim 1, characterized in that, In step S2, the reduction temperature is 1200~1300℃; and / or, in step S2, the atmosphere of the reduction process includes carbon monoxide, wherein the volume percentage of carbon monoxide is 3~8%.

5. The smelting method according to any one of claims 1 to 4, characterized in that, In step S1, the smelting products also include oxidized waste dust and oxidized waste gas; the oxidized waste dust is recycled as a raw material for the mixed granulation.

6. The smelting method according to any one of claims 1 to 4, characterized in that, In step S2, the reduction products also include reduction waste dust and reduction waste gas; the reduction waste dust is recycled as a raw material for the mixed granulation.

7. The smelting method according to any one of claims 1 to 4, characterized in that, In step S2, the reduction product also includes reduced slag.

8. The smelting method according to any one of claims 1 to 4, characterized in that, In step S1, the antimony grade in the antimony ore is ≤40%.

9. The smelting method according to any one of claims 1 to 4, characterized in that, The mass ratio of antimony in the reducing slag to antimony in the antimony ore is ≤0.5%.

10. The smelting method according to any one of claims 1 to 4, characterized in that, The crude antimony contains ≥90% antimony by mass.

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