Method for volatilizing and smelting antimony ore in oxygen-enriched molten pool

Abstract

The invention provides a method for volatilizing and smelting antimony ore in an oxygen-enriched molten pool, and belongs to the technical field of non-ferrous metallurgy. The method comprises the following steps: mixing antimony ore, a calcium-containing material, an iron-containing material, a carbon-containing material and a sulfur-containing material according to a mass ratio of 100: (8-15): (10-35): (0-15): (5-20) to form a charging material; putting the materials in the furnace into a molten pool smelting furnace for oxygen-enriched smelting, and controlling the temperature in the furnace to be 1000-1400 DEG C; high-temperature melt formed by smelting is automatically layered, the upper layer is slag, the middle layer is antimony matte, and the bottom layer is crude antimony or precious antimony; the obtained high-temperature high-concentration antimony-containing flue gas is subjected to oxidative desulfurization, crude Sb2O3 is collected, and the discharged high-temperature flue gas is sent to an acid making system for acid making. According to the method, advanced oxidation of antimony sulfide is avoided by utilizing the characteristics of the sulfur-containing material, and the temperature in the furnace is maintained by utilizing heat released by oxidation of the antimony sulfide, so that the purposes of reducing energy consumption and the antimony content in slag and improving the antimony yield and the sulfur dioxide content in flue gas are achieved, and comprehensive resource utilization of antimony ore is realized. The method is low in cost and can be stably operated in industry.

Description

Technical Field

[0001] The invention relates to the technical field of nonferrous metal metallurgy, and more specifically to a method for volatilization smelting of antimony ore in an oxygen-enriched molten pool. Background Art

[0002] Antimony is one of the ten commonly used nonferrous metals and a typical strategic metal. It is an indispensable key raw material for national defense, military industry, semiconductor and other industries. As the world's largest producer and consumer of antimony products, my country's antimony smelting is still mainly based on the traditional blast furnace volatilization smelting process. Due to its special operating mode of "low material column, thin material layer, high coke rate, and high temperature furnace top", the process has high energy consumption and a coke rate of more than 30%; the flue gas SO2 concentration is low (≤1%), and sulfur resources cannot be recovered through acid production, which seriously pollutes the ecological environment; and the process precious metal recovery rate is low, less than 80%. Therefore, this process can no longer meet the environmental protection requirements under the new situation and urgently needs technological innovation.

[0003] As a mainstream process for intensified smelting, the molten pool smelting process can not only give full play to the advantages of heat release and energy saving of sulfur oxidation in sulfide ores, but also has the advantages of strong raw material adaptability, high production efficiency, and high flue gas SO2 concentration, which is conducive to acid recovery. It has been widely used in the pyrometallurgy of copper and lead, and is regarded by my country's backbone antimony smelting enterprises as the most promising alternative to the blast furnace antimony smelting process. To this end, in recent years, relevant enterprises and research institutions have carried out a large number of experimental research and development work on new processes for antimony smelting in oxygen-enriched molten pools, hoping that during the smelting process, Sb in the antimony sulfide ore will volatilize and oxidize to antimony oxide powder in the flue, while the gangue components such as Fe and Si in the antimony sulfide ore will form FeO-SiO2-CaO slag together with the slag-making agent, and industrial tests of oxygen-enriched molten pool top blowing, bottom blowing, and side blowing smelting have been carried out successively. For example:

[0004] Chinese patent 200710050357.0 discloses a method for smelting lead-antimony ore in an oxygen bath, wherein lead-antimony ore or a mixture of lead-antimony ore and lead concentrate, flux (iron ore, limestone or quartz), smoke and solid fuel are added to molten oxidized bottom slag, and oxidative smelting is performed based on the FeO-CaO-SiO2 slag type. However, the output is a lead-antimony alloy, and the antimony is not volatilized into the gas phase as expected, resulting in an antimony content of more than 5% in the slag, which needs to be further volatilized by fume.

[0005] Chinese patent 201410173492.4 discloses a method and device for producing crude antimony trioxide by oxygen-enriched side-blown volatile bath smelting, wherein antimony-containing materials, anthracite, iron ore, and lime are fed into an oxygen-enriched side-blown volatile bath smelting furnace through a feed port, and the materials undergo melting, dissociation, desulfurization, oxidation, volatilization, and slagging reactions in the furnace, and more than 95% of antimony enters the flue gas to obtain slag, antimony matte, and crude antimony or precious antimony. However, in fact, the process depends on specific equipment. If pyrite (pyrite) is used as a slag-forming agent for iron ore, it is difficult to operate stably because pyrite cannot be smoothly oxidized under experimental conditions, so the iron source therein cannot form the set slag composition as expected, and ultimately due to poor slag fluidity and other reasons, The slag cannot be discharged smoothly from the furnace, so the furnace has to be shut down; and using other iron ores as slag-forming agents not only makes it difficult to operate the process stably, but also the SO2 concentration in the flue gas cannot meet the acid production requirements. The reason is that under this condition, the heating of the furnace can only rely on the oxidation of coke, and the volatilization of antimony sulfide will take away a lot of heat, so a large amount of coke and oxygen have to be added during the smelting process to maintain the furnace temperature through the combustion of coke. At the same time, a large amount of CO gas will be formed, which will dilute the SO2 concentration in the flue gas; on the other hand, due to the addition of a large amount of carbon, the added iron ore may be deeply reduced to metallic iron. Because the melting point of iron is very high, the melt viscosity increases, which also makes it difficult for smelting to operate stably.

[0006] The literature (Nonferrous Metallurgy Design and Research, 2010, 31(6):12-16) reported a semi-industrial test study on the oxygen-enriched top-blown molten pool smelting process of antimony sulfide concentrate. The test used iron ore and limestone as slag-making agents and lump coal as fuel. The test was run continuously for more than 20 days and antimony oxide powder with an antimony content of >78% was obtained. However, due to the large fluctuations in the slag composition and the antimony content in the slag during the test, continuous and stable operation has not been achieved. Sometimes the slag Fe / SiO2 value is very low, only 0.49, and the slag viscosity is very high, which cannot be discharged from the furnace smoothly; sometimes the slag contains antimony Sb as high as 7.81%, which makes the slag unable to be directly discarded.

[0007] The literature (Metallurgical and Materials Transactions B, 2014, 45B: 1281-1290) reported an oxygen-enriched bottom blowing process for antimony refining. However, during the experiment, antimony was produced in the form of high-antimony slag, and the slag contained antimony as high as more than 30%, which could not be directly discarded. The high-antimony slag produced needed to be reduced by an electric furnace to further obtain crude antimony.

[0008] In summary, people have conducted a lot of experimental research on the oxygen-enriched molten pool antimony smelting process, and even carried out semi-industrial experiments, but it has not been able to achieve industrialization. It is difficult to coordinate the volatilization of antimony with the smooth slag formation of silicon and iron in the experimental process. The results show two situations: one is that although the volatilization rate of antimony is very high, the iron cannot be smoothly oxidized and entered into the slag as expected, and thus the target slag composition cannot be obtained; the other is that a large amount of antimony is oxidized into the slag, and even high-antimony slag is formed. At this time, it is impossible to directly discard the slag and obtain a high antimony volatilization recovery rate. Subsequently, Chinese Patent No. 201710764008.9 proposed a new process based on MnO-SiO2-CaO slag-type volatilization smelting to address the problem that the traditional FeO-SiO2-CaO slag-type oxygen-enriched molten pool volatilization antimony smelting process is difficult to operate stably. This process uses manganese-containing materials (manganese carbonate ore, manganese oxide ore, manganese sulfide ore and / or silver-containing manganese ore) as a slag-forming agent for oxygen-enriched molten pool volatilization smelting antimony, and forms MnO-SiO2-CaO slag during the smelting process, which solves the problem of smooth slag formation of antimony and gangue such as silicon. However, due to the high price of manganese ore, the process has not been promoted to industrialization. Summary of the invention

[0009] Based on the technical problem that the prior art cannot operate stably in industry, the purpose of the present invention is to provide a method for volatilization smelting of antimony ore in an oxygen-enriched molten pool, which can increase the SO2 concentration in the flue gas, reduce energy consumption and improve resource utilization.

[0010] In order to achieve the above object, the technical solution of the present invention is as follows:

[0011] A method for volatilization smelting of antimony ore in an oxygen-enriched molten pool comprises the following steps:

[0012] (1) preparing antimony ore, calcium-containing material, iron-containing material, carbon-containing material and sulfur-containing material respectively, and then batching the prepared materials according to a mass ratio of 100:8-15:10-35:0-15:5-20;

[0013] (2) The ingredients of step (1) are put into a molten pool smelting furnace, and oxygen-enriched air is blown into the molten pool to initiate a smelting reaction, and the temperature in the furnace is controlled to be 1000°C to 1400°C; the high-temperature melt formed by smelting is automatically stratified, with the upper layer being slag, the middle layer being antimony matte, and the bottom layer being crude antimony or precious antimony (the gold and silver in the input materials are enriched in the crude antimony to form precious antimony); the resulting high-temperature and high-concentration antimony-containing flue gas is oxidized and desulfurized, and the crude Sb2O3 is collected, and the high-temperature flue gas discharged from the furnace is sent to an acid-making system for acid production.

[0014] Furthermore, in step (1), the antimony ore is an antimony-containing mineral and / or antimony-containing material containing ≥10% antimony; the antimony-containing mineral is one or more of antimony sulfide concentrate, sulfur-oxygen mixed antimony concentrate, antimony oxide concentrate, and antimony-gold ore; the antimony-containing material is one or more of antimony-containing slag and antimony-containing smoke dust; the iron-containing material is one or more of hematite, magnetite, limonite, hematite, and siderite; the sulfur-containing material is one or more of sulfur, elemental sulfur, elemental sulfur, manganese sulfide ore, and high-sulfur manganese ore; the calcium-containing material is one or more of lime and dolomite of limestone; the carbon-containing material is one or more of anthracite, coke, natural gas, coal gas, heavy oil, petroleum coke, coal, and firewood.

[0015] In the present invention, the form of the material entering the furnace is not limited, and it can be powder ore, granular ore or lump ore.

[0016] Furthermore, in step (1), the smelting furnace is an oxygen-enriched top-blowing smelting furnace, an oxygen-enriched bottom-blowing smelting furnace or an oxygen-enriched side-blowing smelting furnace.

[0017] Furthermore, in step (1), in order to ensure the slag / matte separation effect, the mass ratio of iron, manganese, silicon and calcium elements in the materials entering the furnace (including antimony ore, calcium-containing materials, iron-containing materials, carbon-containing materials and sulfur-containing materials) satisfies SiO2: (FeO + MnO): CaO = 1: 0.2 ~ 1.3: 0.2 ~ 0.7.

[0018] Furthermore, the mass ratio of the antimony ore, the calcium-containing material, the iron-containing material, the carbon-containing material and the sulfur-containing material is 100:8-15:10-35:0-10:5-20.

[0019] Furthermore, in step (2), when the high-temperature and high-concentration antimony-containing flue gas passes through the furnace top, it is further oxidized and desulfurized by the secondary air or oxygen-enriched air sent in by the secondary air nozzle, and then the flue gas is passed through the waste heat boiler, the electric dust collector and the bag dust collector to obtain a crude Sb2O3 product, and the flue gas after the bag dust collector is sent to the acid-making system to make acid. The antimony content in the crude Sb2O3 product is ≥70%, the antimony recovery rate is ≥90%, and the SO2 concentration of the high-temperature flue gas discharged from the furnace is ≥8% (V / V).

[0020] Furthermore, in step (2), the slag is discharged through the slag siphon chamber, the antimony matte, crude antimony or precious antimony is discharged through the antimony matte siphon chamber, and a small amount of antimony enters the antimony matte, crude antimony or precious antimony.

[0021] Further, in step (2), oxygen-enriched air is blown to control the oxygen-enriched concentration in the smelting furnace to be 20% to 95% (V / V). More preferably, in step (2), oxygen-enriched air is blown to control the oxygen-enriched concentration in the smelting furnace to be 30% to 80% (V / V).

[0022] Furthermore, in step (2), the smelting temperature is 1100°C to 1350°C.

[0023] Furthermore, in step (2), the produced slag contains ≤1% antimony and can be directly discarded.

[0024] The principle of the present invention is that during the molten pool smelting process, the antimony sulfide has the highest vapor pressure. Once antimony oxide is generated, its volatility becomes worse, and the volatility of metal antimony is even worse. Moreover, once Sb2O3 is generated, it will further react with Sb2S3 to generate metal antimony which is less volatile, thereby reducing the recovery rate of antimony. The relevant reaction equation is as follows:

[0025] Sb2S3+2Sb2O3=6Sb+3SO 2(g)

[0026] Moreover, the volatility of antimony sulfide increases significantly with increasing temperature. Therefore, during the molten pool smelting process, it is necessary to ensure that antimony first volatilizes in the form of antimony sulfide, and then further oxidizes in the gas phase to form antimony oxide. In addition, since the volatilization of antimony sulfide is a gasification process, it needs to absorb a large amount of heat. Therefore, a material that is easier to oxidize than antimony sulfide must be provided in the molten pool. It can oxidize before antimony sulfide, and then shield the oxidation of antimony sulfide, so that antimony can volatilize in the form of antimony sulfide; in addition, its oxidation can also release a large amount of heat, provide heat for the molten pool, and ensure that the molten pool temperature meets the requirements of smelting. In addition, its reaction products do not reduce the SO2 concentration in the flue gas, ensuring that the SO2 in the flue gas can be smoothly recovered by acid production. When adding sulfur-containing materials, such as sulfur, elemental sulfur, manganese sulfide ore, high-sulfur manganese ore, etc., they are easier to oxidize than antimony sulfide, and the oxidation reaction can also release a lot of heat. The sulfur-containing materials are oxidized before antimony sulfide, thereby avoiding the oxidation of antimony sulfide. At the same time, the heat released can maintain the temperature in the furnace; in addition, the SO2 gas produced by oxidation can also increase the SO2 concentration in the flue gas, which is beneficial to its acid recovery. In addition, its advantages are: in the smelting process, extremely abundant and cheap raw materials such as iron ore and calcium oxide are still used as slag-making agents. In addition, the source of sulfur-containing materials is also very abundant and cheap. This provides favorable conditions for the industrial application of the process.

[0027] Compared with the prior art, the advantages of the present invention are:

[0028] (1) The antimony smelting method of the present invention solves the problem that the existing antimony molten pool smelting process cannot be stably operated in industry. It makes full use of the characteristic that sulfur-containing materials are more easily oxidized than antimony sulfide. When sulfur-containing materials are added to the molten pool, they will be oxidized before antimony sulfide, thus avoiding the problem of increased antimony loss in the slag due to the oxidation of antimony sulfide, and also ensuring the stable entry of iron-containing materials into the slag.

[0029] (2) The antimony smelting method of the present invention has obvious advantages in energy saving and environmental protection. The reason is that the oxidation of sulfur-containing materials can release a large amount of heat, which can then provide energy for the molten pool, effectively reducing the amount of carbonaceous fuel used; in addition, the SO2 generated by the oxidation reaction of the sulfur-containing materials can further increase the SO2 concentration in the flue gas, which is beneficial to the acid production and recovery of sulfur resources.

[0030] (3) During the smelting process, the added iron-containing materials, sulfur-containing materials, carbon-containing materials, calcium-containing materials, etc. are widely available and inexpensive, which provides favorable conditions for the industrial application of the process. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a graph showing the relationship between the vapor pressure of antimony and major antimony compounds and temperature. DETAILED DESCRIPTION

[0032] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and meticulously in combination with preferred embodiments below, but the protection scope of the present invention is not limited to the following specific embodiments.

[0033] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0034] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0035] Example 1

[0036] A method for volatilization smelting of antimony ore in an oxygen-enriched molten pool comprises the following steps:

[0037] (1) Antimony ore (sulfur-oxygen mixed antimony concentrate and antimony-containing smoke, the mass ratio of the two is 95:5, and the antimony content is 30%), calcium-containing material (lime), iron-containing material (hematite) and sulfur-containing material (sulfur) are prepared separately, and then the prepared materials are mixed according to the mass ratio of 100:15:30:18, and the mass ratio of SiO2:FeO:CaO in the materials entering the furnace is 1:1.2:0.7.

[0038] (2) The ingredients prepared in step (1) are placed into an oxygen-enriched side-blown smelting furnace, and 80% (V / V) oxygen-enriched air is blown into the molten pool for smelting reaction, and the temperature in the furnace is controlled to be 1200° C. to 1300° C. The high-temperature melt formed by smelting is automatically layered, with the upper layer being slag, the middle layer being antimony matte, and the bottom layer being crude antimony or precious antimony (the gold and silver in the materials entering the furnace are enriched in the crude antimony to form precious antimony). The slag is discharged through the slag siphon chamber, and the antimony matte, crude antimony or precious antimony is discharged through the antimony matte siphon chamber. A small amount of antimony enters the antimony matte, crude antimony or precious antimony, and more than 90% of gold enters the precious antimony. The obtained high-temperature and high-concentration antimony-containing flue gas is further oxidized and desulfurized by the secondary air or oxygen-enriched air sent in by the secondary air nozzle when passing through the furnace top, and then the flue gas is passed through the waste heat boiler, electric dust collector and bag dust collector to obtain a crude Sb2O3 product. The flue gas after bag dust collection is sent to the acid making system for acid making, and the crude Sb2O3 product contains 80.91% antimony, the antimony recovery rate is 97.14%, the slag contains 0.51% antimony, and the SO2 concentration of the high-temperature flue gas discharged from the furnace is 14.06% (V / V). The smelting can be continuously and stably operated for more than 200 days.

[0039] Example 2

[0040] A method for volatilization smelting of antimony ore in an oxygen-enriched molten pool comprises the following steps:

[0041] (1) Antimony ore (antimony concentrate, antimony content 45%), calcium-containing material (limestone), iron-containing material (hematite), carbon-containing material (anthracite) and sulfur-containing material (sulfur concentrate) are prepared separately, and then the prepared materials are mixed according to a mass ratio of 100:8:10:5:5, and the mass ratio of SiO2:FeO:CaO in the materials entering the furnace is 1:0.5:0.3.

[0042] (2) The ingredients prepared in step (1) are placed into an oxygen-enriched side-blown smelting furnace, and 75% (V / V) oxygen-enriched air is blown into the molten pool for smelting reaction, and the temperature in the furnace is controlled to be 1150° C. to 1250° C. The high-temperature melt formed by smelting is automatically layered, with the upper layer being slag, the middle layer being antimony matte, and the bottom layer being crude antimony or precious antimony (the gold and silver in the materials entering the furnace are enriched in the crude antimony to form precious antimony). The slag is discharged through the slag siphon chamber, and the antimony matte, crude antimony or precious antimony is discharged through the antimony matte siphon chamber. A small amount of antimony enters the antimony matte, crude antimony or precious antimony, and more than 90% of gold enters the precious antimony. The obtained high-temperature and high-concentration antimony-containing flue gas is further oxidized and desulfurized by the secondary air or oxygen-enriched air sent in by the secondary air nozzle when passing through the furnace top, and then the flue gas is passed through the waste heat boiler, electric dust collector and bag dust collector to obtain a crude Sb2O3 product. The flue gas after bag dust collection is sent to the acid making system for acid making, and the crude Sb2O3 product contains 81.23% antimony, the antimony recovery rate is 94.71%, the slag contains 0.71% antimony, and the SO2 concentration of the high-temperature flue gas discharged from the furnace is 13.25% (V / V). The smelting can be continuously and stably operated for more than 200 days.

[0043] Example 3

[0044] A method for volatilization smelting of antimony ore in an oxygen-enriched molten pool comprises the following steps:

[0045] (1) Antimony ore (a mixture of antimony concentrate and antimony-gold ore, with an antimony content of 38% and a gold content of 10 g / t), calcium-containing material (limestone), iron-containing material (mixed in a mass ratio of 1:1:1 among hematite, hematite and siderite), carbon-containing material (anthracite) and sulfur-containing material (sulfur concentrate) are prepared separately, and then the prepared materials are mixed in a mass ratio of 100:10:24:5:10, and the mass ratio of SiO2:FeO:CaO in the materials entering the furnace is 1:0.8:0.5.

[0046] (2) The ingredients of step (1) are put into an oxygen-enriched side-blown smelting furnace, and 65% (V / V) oxygen-enriched air is blown into the molten pool to cause smelting reaction, and the temperature in the furnace is controlled to be 1150°C to 1300°C. The high-temperature melt formed by smelting is automatically stratified, with the upper layer being slag, the middle layer being antimony matte, and the bottom layer being crude antimony or precious antimony (the gold and silver in the input materials are enriched in the crude antimony to form precious antimony). The slag is discharged through the slag siphon chamber, and the antimony matte, crude antimony or precious antimony is discharged through the antimony matte siphon chamber. A small amount of antimony enters the antimony matte, crude antimony or precious antimony, and more than 90% of the gold enters the precious antimony. The obtained high-temperature and high-concentration antimony-containing flue gas is fed by the secondary air or oxygen-enriched air supplied by the secondary air nozzle when passing through the furnace top. After further oxidation desulfurization, the flue gas is passed through a waste heat boiler, an electric dust collector and a bag filter to obtain a crude Sb2O3 product. The flue gas after bag filter is sent to the acid making system for acid making. The crude Sb2O3 product contains 80.32% antimony, an antimony recovery rate of 95.67%, a gold recovery rate of 95.89%, an antimony content of 0.71% in the slag, and a SO2 concentration of 18.62% (V / V) in the high-temperature flue gas discharged from the furnace. The smelting can operate continuously and stably for more than 200 days.

[0047] Example 4

[0048] A method for volatilization smelting of antimony ore in an oxygen-enriched molten pool comprises the following steps:

[0049] (1) Antimony ore (antimony concentrate, antimony content 45%), calcium-containing material (limestone), iron-containing material (hematite and magnetite in a mass ratio of 1:1), carbon-containing material (anthracite) and sulfur-containing material (manganese sulfide concentrate) are prepared separately, and then the prepared materials are mixed according to a mass ratio of 100:10:22:6:15, and the mass ratio of SiO2:(FeO+MnO):CaO in the materials entering the furnace is 1:0.35:0.55.

[0050] (2) The ingredients prepared in step (1) are placed into an oxygen-enriched side-blown smelting furnace, and 80% (V / V) oxygen-enriched air is blown into the molten pool for smelting reaction, and the temperature in the furnace is controlled to be 1150° C. to 1250° C. The high-temperature melt formed by smelting is automatically layered, with the upper layer being slag, the middle layer being antimony matte, and the bottom layer being crude antimony or precious antimony (the gold and silver in the materials entering the furnace are enriched in the crude antimony to form precious antimony). The slag is discharged through the slag siphon chamber, and the antimony matte, crude antimony or precious antimony is discharged through the antimony matte siphon chamber. A small amount of antimony enters the antimony matte, crude antimony or precious antimony, and more than 90% of gold enters the precious antimony. The obtained high-temperature and high-concentration antimony-containing flue gas is further oxidized and desulfurized by the secondary air or oxygen-enriched air sent in by the secondary air nozzle when passing through the furnace top, and then the flue gas is passed through the waste heat boiler, electric dust collector and bag dust collector to obtain a crude Sb2O3 product. The flue gas after bag dust collection is sent to the acid making system for acid making, and the crude Sb2O3 product contains 80.23% antimony, the antimony recovery rate is 95.71%, the slag contains 0.56% antimony, and the SO2 concentration of the high-temperature flue gas discharged from the furnace is 14.16% (V / V). The smelting can be continuously and stably operated for more than 200 days.

[0051] Example 5

[0052] A method for volatilization smelting of antimony ore in an oxygen-enriched molten pool comprises the following steps:

[0053] (1) Antimony ore (a mixture of stibnite and antimony oxide, with an average antimony content of 30%), calcium-containing material (limestone), iron-containing material (hematite and magnetite in a mass ratio of 1:1), carbon-containing material (anthracite) and sulfur-containing material (a mixture of sulfur concentrate and manganese sulfide concentrate in a mass ratio of 1:1) are prepared separately, and then the prepared materials are mixed in a mass ratio of 100:15:27:15:12, and the mass ratio of SiO2:(FeO+MnO):CaO in the materials entering the furnace is 1:0.75:0.25.

[0054] (2) The ingredients prepared in step (1) are placed into an oxygen-enriched side-blown smelting furnace, and 40% (V / V) oxygen-enriched air is blown into the molten pool for smelting reaction, and the temperature in the furnace is controlled to be 1150° C. to 1250° C. The high-temperature melt formed by smelting is automatically layered, with the upper layer being slag, the middle layer being antimony matte, and the bottom layer being crude antimony or precious antimony (the gold and silver in the materials entering the furnace are enriched in the crude antimony to form precious antimony). The slag is discharged through the slag siphon chamber, and the antimony matte, crude antimony or precious antimony is discharged through the antimony matte siphon chamber. A small amount of antimony enters the antimony matte, crude antimony or precious antimony, and more than 92% of gold enters the precious antimony. The obtained high-temperature and high-concentration antimony-containing flue gas is further oxidized and desulfurized by the secondary air or oxygen-enriched air sent in by the secondary air nozzle when passing through the furnace top, and then the flue gas is passed through the waste heat boiler, electric dust collector and bag dust collector to obtain a crude Sb2O3 product. The flue gas after bag dust collection is sent to the acid making system for acid making, and the crude Sb2O3 product contains 81.49% antimony, the antimony recovery rate is 94.92%, the slag contains 0.95% antimony, and the SO2 concentration of the high-temperature flue gas discharged from the furnace is 12.17% (V / V). The smelting can be continuously and stably operated for more than 200 days.

[0055] Comparative Example 1

[0056] On the basis of Example 1, no sulfur-containing material is added.

[0057] The SO2 flue gas concentration was only 5.91%, so acid could not be produced smoothly. The slag contained antimony as high as 3.96%, so it could not be directly discarded. The stable operation time was less than 10 days.

[0058] Comparative Example 2

[0059] Based on Example 2, no sulfur-containing material is added.

[0060] The SO2 flue gas concentration was only 7.01%, so acid could not be produced smoothly. The slag contained as much antimony as 5.22%, so it could not be directly discarded. The stable operation time was less than 10 days.

[0061] Comparative Example 3

[0062] On the basis of Example 1, the iron-containing material is pyrite, and no sulfur-containing material is added.

[0063] Antimony ore (sulfur-oxygen mixed antimony concentrate and antimony-containing smoke, the mass ratio of the two is 95:5, and the antimony content is 30%), calcium-containing material (lime) and pyrite are added into the furnace in a mass ratio of 100:15:50. Since the pyrite cannot be smoothly oxidized into slag, the SO2 flue gas concentration is only 4.31%, and acid cannot be produced smoothly. The antimony content in the slag is as high as 2.57%, which cannot be directly discarded. The stable operation time is less than 5 days.

[0064] Comparative Example 4

[0065] On the basis of Example 1, the iron-containing material is pyrite, and a sulfur-containing material is added.

[0066] Antimony ore (sulfur-oxygen mixed antimony concentrate and antimony-containing smoke, the mass ratio of the two is 95:5, and the antimony content is 30%), calcium-containing materials (lime), pyrite, and sulfur-containing materials are added into the furnace in a mass ratio of 100:15:50:18. Since sulfur can be smoothly oxidized, the SO2 concentration in the flue gas can be increased to 12.78%, and its oxidation energy can provide heat for the furnace; however, since pyrite still cannot be smoothly oxidized, FeO-SiO2-CaO slag of the target composition cannot be formed in the molten pool, and the slag fluidity and other requirements for smooth discharge from the furnace are not met. Finally, because the slag cannot be smoothly discharged from the furnace, the stable operation time of the smelting process is less than 10 days, which cannot meet the requirements of industrial production.

[0067] From Comparative Examples 1 and 2, it can be seen that without adding sulfur-containing materials, the SO2 concentration in the tail gas is low and the slag cannot be directly discarded. From the comparison between Comparative Examples 3-4 and Example 1, it can be seen that, combined with Figure 1 Conventional pyrite cannot meet the process requirements because FeS is more difficult to oxidize than Sb2S3. When it is added to the molten pool, under the condition that antimony sulfide is not oxidized, FeS can neither be oxidized to form slag, so the target composition of FeO-SiO2-CaO slag cannot be formed in the molten pool, and the slag fluidity and other requirements for smooth discharge from the furnace cannot be met; in addition, FeS cannot be smoothly oxidized to release heat, which will also lead to the temperature in the furnace failing to reach the expected target, and the slag cannot be smoothly melted, so the final smelting process cannot run stably for a long time.

[0068] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for volatilization smelting of antimony ore in an oxygen-enriched molten pool, characterized in that: The following steps are involved: (1) preparing antimony ore, calcium-containing material, iron-containing material, carbon-containing material and sulfur-containing material respectively, and then batching the prepared materials according to a mass ratio of 100:8-15:10-35:0-15:5-20 to form furnace materials; (2) The materials in step (1) are placed into a molten pool smelting furnace, and oxygen-enriched air is blown into the molten pool smelting furnace to initiate a smelting reaction, and the temperature in the furnace is controlled to be 1000°C to 1400°C; the high-temperature melt formed by smelting is automatically stratified, with the upper layer being slag, the middle layer being antimony matte, and the bottom layer being crude antimony or precious antimony; the resulting high-temperature and high-concentration antimony-containing flue gas is oxidized and desulfurized, and the crude Sb2O3 is collected, and the high-temperature flue gas discharged from the furnace is sent to an acid-making system for acid production.

2. The method for volatilization smelting of antimony ore in an oxygen-enriched molten pool according to claim 1, characterized in that: In step (1), the antimony ore is an antimony-containing mineral and / or antimony-containing material containing ≥10% antimony; the iron-containing material is one or more of hematite, magnetite, limonite, hematite, and siderite; the calcium-containing material is one or more of lime and dolomite of limestone; the sulfur-containing material is one or more of sulfur, elemental sulfur, elemental sulfur, manganese sulfide ore, and high-sulfur manganese ore; the carbon-containing material is one or more of anthracite, coke, natural gas, coal gas, heavy oil, petroleum coke, coal, and firewood.

3. The method for volatilization smelting of antimony ore in oxygen-enriched molten pool according to claim 2, characterized in that: The antimony-containing mineral is one or more of antimony sulfide concentrate, sulfur-oxygen mixed antimony concentrate, antimony oxide concentrate, and antimony-gold ore; the antimony-containing material is one or more of antimony-containing slag and antimony-containing smoke and dust.

4. The method for antimony ore oxygen-enriched molten pool volatilization smelting according to claim 1, characterized in that: In step (1), the smelting furnace is an oxygen-enriched top-blowing smelting furnace, an oxygen-enriched bottom-blowing smelting furnace or an oxygen-enriched side-blowing smelting furnace.

5. The method for volatilization smelting of antimony ore in oxygen-enriched molten pool according to claim 1, characterized in that: The mass ratio of iron, manganese, silicon and calcium elements in the materials entering the furnace is SiO2: (FeO+MnO): CaO = 1: 0.2~1.3: 0.2~0.

7.

6. The method for volatilization smelting of antimony ore in oxygen-enriched molten pool according to claim 1, characterized in that: In step (2), the high-temperature and high-concentration antimony-containing flue gas is further oxidized and desulfurized by the secondary air or oxygen-enriched air sent in by the secondary air nozzle when passing through the furnace top, and then the flue gas is passed through the waste heat boiler, electric dust collector and bag dust collector to obtain a crude Sb2O3 product. The high-temperature flue gas discharged from the furnace after bag dust collection is sent to the acid-making system for acid production; the antimony grade in the crude Sb2O3 product is ≥70%, the antimony recovery rate is ≥90%, and the SO2 concentration of the high-temperature flue gas discharged from the furnace is ≥8% (V / V).

7. The method for antimony ore oxygen-enriched molten pool volatilization smelting according to claim 1, characterized in that: In step (2), the oxygen enrichment concentration in the smelting furnace is 20% to 95% (V / V).

8. The method for antimony ore oxygen-enriched molten pool volatilization smelting according to claim 7, characterized in that: In step (2), the oxygen enrichment concentration in the smelting furnace is 30% to 80% (V / V).

9. The method for volatilization smelting of antimony ore in oxygen-enriched molten pool according to claim 1, characterized in that: In step (2), the smelting temperature is 1100°C to 1350°C.

10. The method for antimony ore oxygen-enriched molten pool volatilization smelting according to claim 1, characterized in that: In step (2), the produced slag contains antimony ≤ 1%.

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