Indium tin smelting method capable of improving smelting efficiency

Abstract

The invention discloses an indium tin smelting method capable of improving smelting efficiency, which comprises the following steps: 1) smelting: feeding polymetallic zinc ore into an oxidizing furnace for smelting to produce oxidized flue gas and smelting slag, and preparing sulfuric acid from the oxidized flue gas; the smelting slag, the granules and the reduction coal are mixed and smelted by adopting a stirring molten pool with a lead rain condenser; (2) carrying out multi-stage distillation on the crude zinc alloy; and (3) the indium-tin-zinc alloy is subjected to crushing, primary leaching, extraction and reverse extraction, sodium carbonate tin deposition, zinc replacement and crude indium electrolysis, and tin and indium are obtained. According to the method, heat and mass transfer is enhanced in the reaction process in smelting, the smelting efficiency is improved, enrichment of elements such as copper in raw materials in a sulfide or metal state is facilitated, and the metal recovery rate is improved; and harmful organic matter impurities in the waste can be decomposed and converted into non-toxic substances at high temperature, fluorine and calcium fluoride are solidified in the slag, and it is guaranteed that the slag is harmless.

Description

Technical Field

[0001] The invention relates to the technical field of ore smelting, and in particular to an indium tin smelting method for improving smelting efficiency. Background Art

[0002] my country has rich reserves of mineral resources, and polymetallic zinc ore resources are also a part of the mineral resources. For this part of resources, due to rough development and utilization, a large amount of resources have been wasted.

[0003] In the process of lead and zinc ore smelting and downstream development, a large amount of indium tin mixture will be produced, and waste powder will be produced in the ITO powder production process; in addition, waste indium tin solder will also be produced in the sputtering production of coating. These waste materials such as waste targets, waste powder, waste indium tin solder, etc. are all indium tin mixtures and have high economic value for recycling.

[0004] In addition, in the zinc ore smelting technology of the prior art, there is a problem of low recovery rate for other valuable metals, which seriously affects economic benefits and work efficiency and causes certain economic losses to the enterprise.

[0005] Therefore, there is an urgent need for an indium tin smelting method that improves smelting efficiency to solve the above problems. Summary of the invention

[0006] The object of the present invention is to provide an indium tin smelting method with improved smelting efficiency.

[0007] The scheme of the present invention is:

[0008] An indium tin smelting method for improving smelting efficiency comprises the following steps:

[0009] 1) Smelting: the polymetallic zinc ore is fed into an oxidation furnace for smelting, and oxidized flue gas and smelting slag are produced. The oxidized flue gas is used to produce sulfuric acid. The smelting slag, pellets and reducing coal are mixed and smelted in a stirring molten pool with a lead rain condenser. The smelting temperature is 1250-1350°C, and the temperature of oxygen-enriched air entering the furnace is 800-1000°C. Crude zinc alloy, crude mixed metal and slag are produced. The pellets include recycled materials, flux, sodium silicate and water, which are mixed and dried to form 0.1-2 cm pellets.

[0010] 2) The crude zinc alloy is subjected to multi-stage distillation, and the multi-stage distillation includes primary vacuum distillation, secondary vacuum distillation, tertiary vacuum distillation and quaternary vacuum distillation. The crude zinc alloy is subjected to primary vacuum distillation, and the primary vacuum distillation temperature is 650-750° C., and zinc-cadmium alloy and zinc-indium-tin bottom liquid are produced; the zinc-cadmium alloy is subjected to secondary vacuum distillation, and the secondary vacuum distillation temperature is 600-650° C., and pyrometallurgical distillation zinc and high-cadmium zinc alloy are produced. The pyrometallurgical distillation zinc is cast and cooled to obtain a zinc ingot product; the high-cadmium zinc alloy is subjected to tertiary vacuum distillation, and the tertiary vacuum distillation temperature is 500-600° C., and a crude cadmium product and a low-cadmium zinc alloy are obtained, and the low-cadmium zinc alloy is returned to the secondary vacuum distillation; the zinc-indium-tin bottom liquid is subjected to quaternary vacuum distillation, and the quaternary vacuum distillation temperature is 950-1000° C., and a high-indium-tin zinc alloy and high-temperature crude zinc are produced, and the high-temperature crude zinc is returned to the primary vacuum distillation;

[0011] 3) The indium-tin-zinc alloy is crushed, leached once, extracted and stripped, tin is precipitated with soda ash, replaced with zinc, and electrolyzed with crude indium to obtain tin and indium.

[0012] As a preferred technical solution, the polymetallic zinc ore is fed into an oxidation furnace for smelting, and the oxidation smelting temperature is 1200-1300°C.

[0013] As a preferred technical solution, a stirred molten pool with a lead rain condenser is used for smelting and oxygen-enriched blowing is adopted.

[0014] As a preferred technical solution, the recycled material is one or more of smoke containing tin and indium, ITO waste and multi-metal zinc and tin industrial waste, and the flux is one or more of calcium oxide, silicon dioxide and iron disulfide.

[0015] As a preferred technical solution, the mass ratio of the recycled material, flux and sodium silicate is 1:0.1-0.3:0.06; and the particles are dried to a moisture content of less than 1%.

[0016] As a preferred technical solution, the mass ratio of the sum of the mass of the smelting slag and the granular material to the mass of the reducing coal is 1:0.3-0.5.

[0017] As a preferred technical solution, the oxygen-enriched air includes oxygen and air; the oxygen content in the oxygen-enriched air is 40-60 vol%.

[0018] As a preferred technical solution, the crushing in step 3) is mechanical crushing.

[0019] As a preferred technical solution, the oxygen concentration injected into the oxidation furnace for smelting is 30%; the smelting time of the stirred molten pool with lead rain condenser is 30 to 50 minutes, and the logarithm of the sulfur partial pressure is -7 to -5.

[0020] Advantages of the present invention:

[0021] The present invention strengthens the heat and mass transfer in the reaction process of smelting slag, smoke containing tin and indium, ITO waste and multi-metal zinc and tin industrial waste during smelting, improves the smelting efficiency, is conducive to the enrichment of elements such as copper in the raw materials in the form of sulfide or metal, and is conducive to improving the metal recovery rate; and can decompose harmful organic impurities in the waste into non-toxic substances at high temperature, and solidify fluorine in the slag as calcium fluoride, which is conducive to ensuring that the slag is harmless.

[0022] It is beneficial to improve the treatment efficiency of smoke containing tin and indium, ITO waste and multi-metal zinc and tin industrial waste, and reduce the treatment energy consumption of smelting. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a process framework diagram of the present invention. DETAILED DESCRIPTION

[0024] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments.

[0025] The following examples are only used to further illustrate the present invention in detail, but do not constitute any limitation to the present invention; the materials used in the following examples, unless otherwise specified, were purchased from conventional chemical reagent companies and raw material suppliers.

[0026] Embodiment 1:

[0027] A polymetallic zinc ore containing Fe12%, In0.04%, Cu0.1%, Cd0.2%, Ag0.01%, Sn0.1%, Zn42%, S26%;

[0028] 1) Smelting, the polymetallic zinc ore is added into the oxidation furnace at a rate of 10t / h for smelting, the oxidation smelting temperature is 1200℃, oxidation flue gas and smelting slag are produced, and sulfuric acid is produced from the oxidation flue gas; the smelting slag, granular material and reducing coal are mixed and smelted in a stirring molten pool with two lead rain condensers, the smelting temperature is 1250℃, the temperature of oxygen-enriched air entering the furnace is 800℃, and crude zinc alloy, crude mixed metal and slag are produced; the granular material includes recycled material, flux, sodium silicate and water, which are mixed and dried to form 0.1cm granular material; the daily output of crude zinc alloy contains Zn98.2%, In0.012%, Cu0.02%, Cd0.54%, Sn0.06%, and the daily output of crude mixed metal contains Cu87.3%, Fe2.1%, In0.018%, Ag4.3%, Sn6.7%.

[0029] 2) The crude zinc alloy is subjected to multi-stage distillation, wherein the multi-stage distillation is a multi-stage vacuum distillation, wherein the distillation stage above 950° C. in the multi-stage vacuum distillation produces an indium tin zinc alloy and crude zinc, and the crude zinc is returned to the distillation stage at 650-750° C. in the multi-stage distillation;

[0030] 3) The indium tin zinc alloy is processed by the process of "mechanical crushing, dilute sulfuric acid dissolution, P204 organic matter extraction, hydrochloric acid stripping, soda ash precipitation, zinc ingot replacement, and crude indium electrolysis", with each batch processing 1.0t, producing a refined indium product containing 99.995% In and recovering a tin raw material containing 53.8% Sn.

[0031] A stirred molten pool with a lead rain condenser is used for smelting and oxygen-enriched blowing is adopted.

[0032] The recycled material is smoke containing 53.25% Sn, 2.62% Pb, 1.12% Fe, 0.01% Cu, 3.412% Zn and 0.598% S, and the flux is calcium oxide.

[0033] The mass ratio of the recycled material, flux and sodium silicate is 1:0.1:0.06; the particles are dried until the moisture content is less than 1%.

[0034] The mass ratio of the sum of the mass of the smelting slag and the granular material to the mass of the reducing coal is 1:0.3.

[0035] The oxygen-enriched air includes oxygen and air; the content of oxygen in the oxygen-enriched air is 40 vol%.

[0036] The 3) crushing is mechanical crushing.

[0037] The oxygen concentration injected into the oxidation furnace for smelting is 30%; the smelting time of the stirring molten pool with lead rain condenser is 30 to 50 minutes, and the logarithm of the sulfur partial pressure is -7 to -5.

[0038] Embodiment 2:

[0039] The zinc concentrate containing Fe18%, In0.09%, Cu0.2%, Cd0.3%, Ag0.018%, Sn0.16%, Zn48%, S27% is

[0040] 1) Smelting: 10 t / h of polymetallic zinc ore is added to an oxidation furnace for smelting. The oxidation smelting temperature is 1250°C, and oxidation flue gas and smelting slag are produced. Sulfuric acid is produced from the oxidation flue gas. The smelting slag, pellets and reducing coal are mixed and smelted in a stirring molten pool with two lead rain condensers. The smelting temperature is 1300°C, and the temperature of oxygen-enriched air entering the furnace is 900°C. Crude zinc alloy, crude mixed metal and slag are produced. The pellets include recycled materials, flux, sodium silicate and water, which are mixed and dried to form 1 cm pellets.

[0041] The daily output of crude zinc alloy contains 98.9% Zn, 0.042% In, 0.02% Cu, 0.83% Cd, and 0.16% Sn; the daily output of crude mixed metal contains 85.2% Cu, 2.6% Fe, 0.015% In, 3.8% Ag, and 5.2% Sn.

[0042] 2) The crude zinc alloy is subjected to multi-stage distillation, wherein the multi-stage distillation is a multi-stage vacuum distillation, wherein the distillation stage above 950° C. in the multi-stage vacuum distillation produces an indium tin zinc alloy and crude zinc, and the crude zinc is returned to the distillation stage at 650-750° C. in the multi-stage distillation;

[0043] 3) The indium tin zinc alloy is processed by the process of "mechanical crushing, dilute sulfuric acid dissolution, P204 organic matter extraction, hydrochloric acid stripping, soda ash precipitation, zinc ingot replacement, and crude indium electrolysis", with each batch processing 1.0t, producing a refined indium product containing 99.995% In and recovering a tin raw material containing 54.1% Sn.

[0044] A stirred molten pool with a lead rain condenser is used for smelting and oxygen-enriched blowing is adopted.

[0045] The recycled material is ITO waste containing 10% SnO2, and the flux is iron disulfide.

[0046] The mass ratio of the recycled material, flux and sodium silicate is 1:0.2:0.06; the particles are dried until the moisture content is less than 1%.

[0047] The mass ratio of the sum of the mass of the smelting slag and the granular material to the mass of the reducing coal is 1:0.4.

[0048] The oxygen-enriched air includes oxygen and air; the content of oxygen in the oxygen-enriched air is 50 vol%.

[0049] The oxygen concentration injected into the oxidation furnace for smelting is 30%; the smelting time of the stirring molten pool with lead rain condenser is 40 minutes, and the logarithm of the sulfur partial pressure is -7 to -5.

[0050] Embodiment 3:

[0051] Zinc concentrate containing Fe21%, In0.12%, Cu0.4%, Cd0.3%, Ag0.03%, Sn0.4%, Zn48%, S15%.

[0052] 1) Smelting: 10 t / h of polymetallic zinc ore is added to an oxidation furnace for smelting. The oxidation smelting temperature is 1300°C, and oxidation flue gas and smelting slag are produced. Sulfuric acid is produced from the oxidation flue gas. The smelting slag, pellets and reducing coal are mixed and smelted in a stirring molten pool with a lead rain condenser. The smelting temperature is 1350°C, and the temperature of oxygen-enriched air entering the furnace is 1000°C. Crude zinc alloy, crude mixed metal and slag are produced. The pellets include recycled materials, flux, sodium silicate and water, which are mixed and dried to form 2 cm pellets.

[0053] The daily output of crude zinc alloy contains Zn98.3%, Cu0.03%, In0.035%, Cd0.75%, Sn0.18%, and the daily output of crude mixed metal contains Cu85.4%, Fe2.6%, In0.012%, Ag2.6%, Sn3.6%;

[0054] 2) The crude zinc alloy is subjected to multi-stage distillation, wherein the multi-stage distillation is a multi-stage vacuum distillation, wherein the distillation stage above 950° C. in the multi-stage vacuum distillation produces an indium tin zinc alloy and crude zinc, and the crude zinc is returned to the distillation stage at 650-750° C. in the multi-stage distillation;

[0055] 3) The indium tin zinc alloy is processed by the process of "mechanical crushing, dilute sulfuric acid dissolution, P204 organic matter extraction, hydrochloric acid stripping, soda ash precipitation, zinc ingot replacement, and crude indium electrolysis", with each batch processing 1.0t, producing a refined indium product containing 99.995% In and recovering a tin raw material containing 52.6% Sn.

[0056] A stirred molten pool with a lead rain condenser is used for smelting and oxygen-enriched blowing is adopted.

[0057] The recycled material is multi-metal zinc-tin industrial waste containing 0.42% Zn and 1.8% Sn, and the flux is calcium oxide.

[0058] The mass ratio of the recycled material, flux and sodium silicate is 1:0.3:0.06; the particles are dried until the moisture content is less than 1%.

[0059] The mass ratio of the sum of the mass of the smelting slag and the granular material to the mass of the reducing coal is 1:0.5.

[0060] The oxygen-enriched air includes oxygen and air; the content of oxygen in the oxygen-enriched air is 60 vol%.

[0061] The oxygen concentration injected into the oxidation furnace for smelting is 30%; the smelting time of the stirring molten pool with lead rain condenser is 50 minutes, and the logarithm of the sulfur partial pressure is -7 to -5.

[0062] The multi-stage vacuum distillation comprises a first-stage vacuum distillation, the first-stage vacuum distillation temperature is 750° C., and zinc-cadmium alloy and zinc-indium-tin bottom liquid are produced; the zinc-cadmium alloy enters a second-stage vacuum distillation, the second-stage vacuum distillation temperature is 650° C., and vacuum distilled zinc and high-cadmium zinc alloy are produced, and the vacuum distilled zinc is cast and cooled to obtain a zinc ingot product; the high-cadmium zinc alloy enters a third-stage vacuum distillation, the third-stage vacuum distillation temperature is 600° C., and a low-cadmium zinc alloy is obtained, and the low-cadmium zinc alloy is returned to the cadmium tower for a second-stage vacuum distillation; the zinc-indium-tin bottom liquid enters a fourth-stage vacuum distillation, the fourth-stage vacuum distillation temperature is 1000° C., and 0.06 t / h of high-indium-tin zinc alloy and high-temperature crude zinc are produced, and the high-temperature crude zinc is returned to the lead tower for a first-stage vacuum distillation;

[0063] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for smelting indium tin with improved smelting efficiency, characterized in that: The following steps are involved: 1) Smelting: the polymetallic zinc ore is fed into an oxidation furnace for smelting, and oxidized flue gas and smelting slag are produced. The oxidized flue gas is used to produce sulfuric acid. The smelting slag, pellets and reducing coal are mixed and smelted in a stirring molten pool with a lead rain condenser. The smelting temperature is 1250-1350°C, and the temperature of oxygen-enriched air entering the furnace is 800-1000°C. Crude zinc alloy, crude mixed metal and slag are produced. The pellets include recycled materials, flux, sodium silicate and water, which are mixed and dried to form 0.1-2 cm pellets. 2) The crude zinc alloy is subjected to multi-stage distillation to produce a high-indium-tin zinc alloy and high-temperature crude zinc, and the high-temperature crude zinc is returned to the first-stage vacuum distillation in the multi-stage distillation; 3) The indium-tin-zinc alloy is crushed, leached once, extracted and stripped, tin is precipitated with soda ash, replaced with zinc, and electrolyzed with crude indium to obtain tin and indium.

2. The indium tin smelting method for improving smelting efficiency according to claim 1, characterized in that: The recycled material is one or more of smoke containing tin and indium, ITO waste and multi-metal zinc and tin industrial waste, and the flux is one or more of calcium oxide, silicon dioxide and iron disulfide.

3. The indium tin smelting method for improving smelting efficiency according to claim 1, characterized in that: The mass ratio of the recycled material, flux and sodium silicate is 1:0.1-0.3:0.06; the particles are dried to have a water content of less than 1%.

4. The indium tin smelting method for improving smelting efficiency according to claim 1, characterized in that: The mass ratio of the sum of the mass of the smelting slag and the granular material to the mass of the reducing coal is 1:0.3-0.

5.

5. The indium tin smelting method for improving smelting efficiency according to claim 1, characterized in that: The oxygen-enriched air includes oxygen and air; the content of oxygen in the oxygen-enriched air is 40-60 vol%.

6. The indium tin smelting method for improving smelting efficiency according to claim 1, characterized in that: The 3) crushing is mechanical crushing.

7. The indium tin smelting method for improving smelting efficiency according to claim 1, characterized in that: The oxygen concentration injected into the oxidation furnace for smelting is 30%; the smelting time of the stirring molten pool with lead rain condenser is 30 to 50 minutes, and the logarithm of the sulfur partial pressure is -7 to -5.

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