Method for efficiently separating arsenic in arsenic-containing material through oxygen-enriched side-blown molten pool smelting

Abstract

The invention discloses a method for efficiently separating arsenic from an arsenic-containing material through smelting of an oxygen-enriched side-blown molten pool. The treated arsenic-containing material, a flux and reduction coal are subjected to batching, a mixed material obtained after batching is continuously put into an oxygen-enriched side-blown molten pool smelting furnace, and oxygen-enriched air and gas fuel are blown into the smelting furnace for heating and high-temperature smelting; the materials are subjected to melting, reduction and slagging reaction in the smelting furnace; along with the reaction in the smelting furnace, the melt in the furnace is settled and layered, and alloy, sulfonium, furnace slag and high-temperature flue gas are obtained; generated alloy and sulfonium are discharged through a siphon port, and obtained slag is discharged through a slag discharging port; most arsenic and part of metal are volatilized and oxidized and enter high-temperature flue gas; and the generated high-temperature flue gas is subjected to cooling, high-temperature dust collection, shock cooling, low-temperature dust collection and tail gas treatment and then is discharged after reaching the standard. According to the method, the processes of matched treatment of the arsenic-containing materials, strengthened smelting and segmented dust collection are adopted, so that the arsenic content of the obtained crude arsenic oxide accounts for 70-75% of the total amount of the arsenic entering the furnace, the content of other metals is low, and the separation effect of the arsenic is good.

Description

I. Technical Field:

[0001] The present invention relates to the technical field of comprehensive recovery and environmental protection disposal of arsenic-containing hazardous wastes, and particularly relates to a method for recovering valuable metals from arsenic-containing materials and efficiently separating arsenic during non-ferrous metal smelting, that is, a method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blown bath smelting. II. Background Art:

[0002] During the smelting of non-ferrous metals and precious metals, since most concentrates are associated with arsenic elements, they enter the soot, slag, and liquid respectively to form arsenic-containing soot, arsenic slag, and arsenic-containing wastewater. The several main arsenic-containing materials produced are arsenic-containing soot, arsenic-alkali slag, and arsenic sulfide slag; a. Arsenic-containing soot: mainly produced in pyrometallurgical processes, most of its components are oxides and a small amount of sulfides. Most of them are recycled through multiple smelting processes until the arsenic content reaches a certain grade and then discharged out of the system for separate disposal; it will be produced in the matte smelting, converting, and anode slime smelting processes of copper smelting, containing 10-40% arsenic, and also containing metals such as lead, copper, zinc, and bismuth; in lead smelting, it is mainly arsenic-antimony soot produced in the anode slime smelting process, containing 20-40% arsenic, 25-35% antimony, and also containing metals such as lead and bismuth; similar arsenic-containing soot will also be produced during the pyrometallurgical processes of other metals. b. Arsenic-alkali slag: produced during the refining of crude antimony, its components are 25-35% arsenate, the main phase is Na3AsO4, 35-45% antimony and its compounds, the main phase is Sb, Na3SbO3; among them, elemental antimony is mainly due to incomplete separation and being carried out of the furnace during manual slag skimming. c. Arsenic sulfide slag: produced during the treatment of arsenic-containing sewage by the sulfide process. The main phases of arsenic in the above several types of arsenic-containing materials are oxides and arsenates, with a small amount of arsenic sulfide. Traditional treatment methods include pyrometallurgical treatment, hydrometallurgical treatment, and pyrometallurgical-hydrometallurgical combined treatment. The existing treatment methods all have problems to varying degrees, such as high cost, long process, poor arsenic separation effect, and the subsequent processes and disposal of the arsenic products are difficult. The following briefly summarizes the existing treatment methods for the three arsenic-containing materials:

[0003] 1. Pyrometallurgical treatment:

[0004] Process description: Pyrometallurgical treatment of arsenic-containing materials is to volatilize arsenic in the form of gas under high-temperature reducing conditions, so as to achieve the separation of arsenic from valuable metals. The commonly used one is the rotary kiln process.

[0005] Advantages: The treatment process is relatively simple. For some high-grade arsenic-containing materials, it can quickly achieve the preliminary separation of arsenic, and some valuable metals can be recovered simultaneously during the treatment process, and the treatment efficiency is relatively high.

[0006] Disadvantages: The temperature and atmosphere control of this treatment process are uneven, inaccurate, and the mass and heat transfer are poor; the cost is high, and a large amount of energy is required to maintain high-temperature reaction conditions; the arsenic separation effect is not ideal, and the recycled products still contain a relatively high content of arsenic; the arsenic products produced have many impurities, and the subsequent processes and disposal are more difficult; the process level is low, and the on-site environment is poor.

[0007] 2. Wet treatment:

[0008] Process description: By using the method of acid leaching or alkali leaching, the arsenic in the arsenic-containing material is dissolved into the solution, and then through subsequent processes such as precipitation and extraction, the arsenic is separated from the solution.

[0009] Advantages: The reaction conditions are relatively mild, generally carried out at room temperature, and the energy consumption is low; the selectivity for arsenic is high, and the purity of the obtained arsenic products is relatively high; less waste gas is generated during the treatment process, and the air pollution is small.

[0010] Disadvantages: This treatment process is long, involving multiple chemical reaction steps and separation operations, and a large amount of chemical reagents need to be used, resulting in a high cost; due to the corrosiveness of chemical reagents, corrosion-resistant equipment needs to be used, increasing the equipment investment; the subsequent treatment of arsenic-containing products (mainly arsenates) is difficult; a large amount of wastewater is generated during the treatment process, and the treatment is difficult; for some complex arsenic-containing materials, the treatment effect is not ideal, and the recovery rate of some valuable metals is low.

[0011] 3. Pyrometallurgical-hydrometallurgical combined treatment method:

[0012] Process description: This method combines the advantages of pyrometallurgy and hydrometallurgy. First, the arsenic-containing material is preliminarily treated by pyrometallurgy to volatilize or enrich the arsenic, and then the product after pyrometallurgical treatment is further refined and separated by hydrometallurgy. For example: First, through pyrometallurgical smelting, the arsenic in the arsenic-containing material volatilizes into the flue gas, and the arsenic in the flue gas is collected to obtain a crude arsenic product, and then the crude arsenic product is purified by hydrometallurgy.

[0013] Advantages: This combined treatment method can comprehensively utilize the advantages of pyrometallurgy and hydrometallurgy, and to a certain extent improve the arsenic separation effect and product quality; compared with single pyrometallurgy or hydrometallurgy, it has stronger adaptability to complex arsenic-containing materials and can treat different types and grades of arsenic-containing materials.

[0014] Disadvantages: This combined treatment process is complex, the process is long, and the operation difficulty is large; the equipment investment is large, and relevant equipment for both pyrometallurgy and hydrometallurgy needs to be equipped at the same time, and the maintenance and management requirements are high; the cost is high, and it is necessary to bear both the high-temperature energy consumption cost of pyrometallurgy and the chemical reagent and equipment costs of hydrometallurgy; the types of pollutants generated are many, the treatment is difficult, and the potential risk to the environment is large.

[0015] The oxygen-enriched bath smelting process is an advanced smelting process that emerged in China at the beginning of this century. Due to its strong adaptability to raw materials, fast heat and mass transfer, fast information conduction, and high automation level, it has been rapidly promoted in the metal smelting and comprehensive recovery industries such as copper, lead, nickel, and tin. In addition to the above advantages, the oxygen-enriched side-blowing bath smelting process has a very strong ability to adjust the furnace atmosphere, and can be used as both an oxidation furnace and a reduction furnace; the melt temperature and composition in the dynamic bath are uniform and can be precisely controlled; a relatively static hearth is provided at the lower part of the furnace body to collect the metal and matte generated in the smelting area.

[0016] In the process of cooling and dust collection of high-temperature flue gas in gold concentrate and copper-gold ore smelting, taking advantage of the characteristics of high vapor pressure, low condensation temperature of arsenic oxide, and the generation of vitreous crystals in the 175 - 250 °C section, after collecting metal dust with an electrostatic precipitator in the high-temperature section (250 - 450 °C), the temperature is rapidly cooled below 150 °C to condense arsenic oxide and then collect dust, so as to separate arsenic oxide from other valuable metals. However, the electrostatic precipitator has a certain adaptability range for the resistivity of the collected metal dust (104 - 1010 Ω·cm), and the dust collection efficiency for dust with resistivity outside this range (such as antimony oxide and lead oxide dust) will be greatly reduced, especially when dealing with complex materials, the adaptability is poor; at the same time, there is a lack of in-depth research on the process control of two-stage dust collection and the separation effect of arsenic, and the separation effect of arsenic needs to be improved.

[0017] In recent years, the emerging dust collection process using intermetallic compound membrane separation technology has developed and been applied rapidly in the metallurgical and chemical industries due to its characteristics of high adaptability temperature (up to 500 °C in some cases), corrosion resistance, high dust collection efficiency, and being unaffected by the resistivity of dust. However, it also has the disadvantages of high cost, large brittleness of materials, insufficient thermal shock resistance and flexibility, and large wind resistance. III. Summary of the Invention:

[0018] The technical problem to be solved by the present invention is: aiming at the disadvantages of high cost, long process, poor arsenic separation effect, and difficult subsequent processes and disposal of arsenic products in the traditional process for treating high-arsenic materials of non-ferrous metals, the present invention provides a method for efficiently separating arsenic from arsenic-containing materials by using oxygen-enriched side-blowing bath smelting. The technical solution of the present invention adopts a process of combined treatment of arsenic-containing materials, enhanced smelting, and staged dust collection, so that the obtained crude arsenic oxide contains 70 - 75% of the total arsenic in the furnace charge, with low content of other metals and good arsenic separation effect.

[0019] To solve the above problems, the technical solution adopted by the present invention is:

[0020] The present invention provides a method for efficiently separating arsenic from arsenic-containing materials by using oxygen-enriched side-blowing bath smelting, and the method includes the following steps:

[0021] 1) Material preparation: The massive arsenic-containing materials are crushed, and the arsenic-containing dust is granulated to obtain arsenic-containing pellets; then the arsenic-containing pellets are proportioned with fluxes and reducing coal to obtain a mixed material;

[0022] 2) Bath smelting: Continuously feed the mixed material obtained from proportioning into an oxygen-enriched side-blowing bath smelting furnace, then blow in oxygen-enriched air and gaseous fuel for high-temperature smelting; control the temperature in the furnace at 1000 - 1250 °C and the bath depth at 1400 - 2400 mm, so that the materials undergo melting, reduction, and slagging reactions in the smelting furnace, strengthening the reduction and volatilization processes of arsenic;

[0023] 3) Furnace charge separation: As the reaction in the smelting furnace proceeds, the melt in the furnace settles and stratifies to obtain alloy, matte, slag, and high-temperature flue gas; when the bath depth reaches 1400 - 2400 mm, the obtained slag is discharged through the slag tapping port; the produced alloy and matte are regularly discharged through the siphon port provided in the hearth; most of the arsenic and some metals are volatilized and oxidized and enter the high-temperature flue gas;

[0024] 4) Flue gas treatment: The generated high-temperature flue gas is cooled by a cooling flue and a waste heat boiler, and after cooling, it is successively dust-collected by a high-temperature dust collector, cooled by a quench tower, and dust-collected in a bag room, and the obtained tail gas is discharged up to the standard after treatment.

[0025] According to the above method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting, the arsenic content grades in the massive arsenic-containing materials and arsenic-containing dust described in step 1) are both 1 - 50%. The arsenic-containing materials are arsenic-containing intermediate materials generated during the smelting of non-ferrous metals such as copper, lead, zinc, antimony, bismuth, etc. and precious metals, and their shapes are massive, semi-solid, or dust.

[0026] According to the above method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting, after the massive arsenic-containing materials in step 1) are crushed, their particle size is 20 - 25 mm; after the arsenic-containing dust is granulated, the particle size of the obtained arsenic-containing pellets is 10 - 25 mm, and the moisture content ≤ 10%.

[0027] According to the above method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting, in step 1), the flux is at least one of iron ore, quartzite, and limestone, and its particle size is 10 - 25 mm; the reducing coal is at least one of coke particles and anthracite particles, the carbon content in the reducing coal > 78%, and its particle size is 10 - 25 mm.

[0028] According to the above method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting, in step 1), the weight ratio of the arsenic-containing pellets to the reducing coal and flux during proportioning is 100:8 - 20:15 - 30.

[0029] According to the method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting described above, in step 2), the oxygen concentration in the oxygen-enriched air is 25-100%, and the air pressure is 0.05-0.15 MPa; the gaseous fuel is natural gas or coal gas, and the air pressure is 0.05-0.15 MPa.

[0030] According to the method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting described above, the slag obtained in step 3) is of the FeO-SiO2-CaO ternary slag type or the FeO-SiO2-CaO-Na2O quaternary slag type.

[0031] Among them: The ternary slag type is the conventional slag type of metallurgical furnaces, with a melting point of 1150°C to 1250°C; when treating arsenic-alkali slag in combination, due to its high alkali content, it becomes one of the main components of the slag; the quaternary slag has a melting point of 1000°C to 1100°C.

[0032] According to the method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting described above, the high-temperature dust collector in step 4) is a high-temperature filtration dust collector based on an intermetallic compound porous membrane, which has stronger adaptability to the complex multi-metal oxide soot generated and higher dust collection efficiency.

[0033] According to the method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting described above, the outlet flue gas temperature of the high-temperature dust collector in step 4) is controlled at 260-290°C, and the temperature control method is shell-and-tube water cooling or air infiltration cooling; the flue gas in the pipeline is evenly mixed, and the temperature difference is controlled at 10-20°C; the collected arsenic soot contains relatively high valuable metals such as lead and antimony, and is sent back to the furnace for treatment.

[0034] According to the method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting described above, the crude arsenic oxide collected after dust collection in the baghouse in step 4) has an arsenic grade of 55-70%, contains less other metals, and can be used to produce high-purity arsenic oxide, metallic arsenic and other arsenic products;

[0035] The arsenic in the collected crude arsenic oxide accounts for 70-75% of the total amount charged into the furnace; the other main metals in the collected crude arsenic oxide are: the antimony content accounts for 4-7% of the total amount of antimony charged into the furnace, the lead content accounts for 2-4.5% of the total amount of lead charged into the furnace, and the copper, bismuth and zinc contents account for 1-3% of the total amount of metals charged into the furnace; the total evaporation rate of arsenic reaches 80-90%, and the separation effect of arsenic is good.

[0036] The main reaction equations of the bath smelting furnace are as follows:

[0037] C + O2 = CO2;

[0038] 2C + O2 = 2CO;

[0039] 2CO + O2 = 2CO2;

[0040] CH4 + 2O2 = CO2 + 2H2O;

[0041] 2Sb2O3 + 3C = 4Sb + 3CO2;

[0042] 2PbO + C = 2Pb + CO2;

[0043] 2Cu2O + C = 4Cu + CO2;

[0044] 2As2O3 + 3C = 4As + 3CO2;

[0045] 2As2S3 + 9O2 = 2As2O3 + 6SO2;

[0046] 2Na3AsO4 + 5C = 2As + 3Na2O + 5CO;

[0047] 2Na3SbO4 + 5C = 2Sb + 3Na2O + 5CO.

[0048] The positive and beneficial effects of the present invention:

[0049] 1. The technical solution of the present invention adopts a process of collocating and treating arsenic-containing materials, strengthening smelting, and sectional dust collection. Different slag types and process parameters are controlled for different types of arsenic-containing materials, and the characteristics of the bath smelting furnace are fully utilized to ensure a relatively high volatilization rate of arsenic. A high-temperature dust collector with an intermetallic compound porous membrane as the base material is adopted, and the flue gas outlet temperature is controlled in the range of 260 - 290 °C, and the flue gas must be mixed evenly with a temperature difference within 10 - 20 °C to collect more valuable metals other than arsenic while minimizing the premature condensation and collection of arsenic oxide vapor. The arsenic content in the separated crude arsenic oxide accounts for 70 - 75% of the total arsenic in the furnace charge, and the content of other metals is relatively low. Therefore, the separation effect of arsenic is better.

[0050] 2. The crude alloy and matte produced by smelting and treating arsenic-containing materials using the technical solution of the present invention can be further used to extract lead, antimony, copper, bismuth, and precious metals; the water-quenched slag produced can be used as a raw material for producing building materials; the crude arsenic oxide produced is a raw material for manufacturing high-purity arsenic oxide, metallic arsenic, and other arsenic products.

[0051] 3. The technical solution of the present invention has a high level of automation and a good on-site environment; it realizes the reduction and harmless treatment of hazardous waste, and has a shorter process and higher efficiency compared with traditional methods.

[0052] In summary, the technical solution of the present invention has significant economic and social benefits. IV. Description of the Drawings:

[0053] Figure 1 Schematic flow chart of the method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting of the present invention. V. Specific implementation manners:

[0054] The present invention will be further elaborated below in conjunction with embodiments, but does not limit the scope of protection of the technical solution of the present invention.

[0055] Embodiment 1:

[0056] The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting of the present invention is as follows in detail (the arsenic-containing materials used in this embodiment are copper smelting arsenic dust, arsenic-antimony dust, returned arsenic dust, and arsenic sulfide slag):

[0057] 1) Material preparation: Mix copper smelting arsenic dust, arsenic-antimony dust, returned arsenic dust, and arsenic sulfide slag according to a weight ratio of 10:10:2:1. The obtained arsenic-containing mixed ingredients are made into arsenic-containing pellet materials with a particle size of 10 - 25 mm and a moisture content of ≤10% by a cylindrical granulator, and the obtained arsenic-containing pellet materials enter a special preparation bin; in addition, anthracite pellets, limestone pellets, and iron ore pellets with a particle size of 10 - 20 mm are prepared and enter the special preparation bin; then the arsenic-containing pellet materials, anthracite pellets, limestone pellets, and iron ore pellets are proportioned according to a weight ratio of 100:18:10:12 to obtain a mixed material (wherein, the arsenic-containing material contains 20.11% arsenic, 10.44% antimony, 12.0% lead, 7.48% copper, and 2.89% zinc);

[0058] 2) Bath smelting: Continuously input the obtained mixed material into an oxygen-enriched side-blowing bath smelting furnace at a feeding speed of 8 - 12 t / h, and then blow in 95% oxygen-enriched air and natural gas for heating and high-temperature smelting (the pressures of the oxygen-enriched air and natural gas are both controlled at 0.09 - 0.12 MPa, and the blown gas strongly stirs the high-temperature melt and participates in the reaction), adopting the FeO - SiO2 - CaO ternary slag type; control the temperature in the furnace at 1200 - 1250 °C and the bath depth at 2100 mm, so that the materials undergo melting, reduction, and slag-making reactions in the smelting furnace, and strengthen the reduction and volatilization processes of arsenic;

[0059] 3) Furnace charge separation: As the reaction in the smelting furnace proceeds, the melt in the furnace settles and stratifies to obtain alloy, matte, slag, and high-temperature flue gas; 2 hours after feeding, when the bath liquid level approaches the bath depth of 2100 mm, slag is discharged. The discharged slag is transported by a slag ladle to a fuming furnace for blowing and recovering zinc oxide powder; the produced alloy and matte are regularly discharged through a siphon port arranged in the hearth, 1 - 2 times every 8 hours; most of the arsenic and part of the metals are volatilized and oxidized and enter the high-temperature flue gas;

[0060] 4) Flue gas treatment: The generated high-temperature flue gas is cooled by a cooling flue and a waste heat boiler, and after cooling, it is sequentially dust-collected by a high-temperature dust collector, cooled by a quenching tower, and dust-collected in a bag house. The obtained tail gas is treated and discharged up to the standard;

[0061] The high-temperature dust collector adopted is a high-temperature filtration dust collector with an intermetallic compound porous membrane as the base material. This dust collector has stronger adaptability to the complex multi-metal oxide soot generated and higher dust collection efficiency;

[0062] The outlet flue gas temperature of the high-temperature dust collector is controlled at 260 - 290 °C. The collected soot contains on average 18.3% antimony, 1.6% copper, 4.8% lead, 1.00% zinc, and 21.2% arsenic, and is sent back to the furnace for treatment; The components and their contents in the crude arsenic oxide collected in the cloth bag chamber are: 3.3% antimony, 0.42% copper, 2.18% lead, 0.28% zinc, and 69.8% arsenic. The total volatilization rate of arsenic is 89.7%;

[0063] The arsenic content in the crude arsenic oxide accounts for 74.7% of the total arsenic in the furnace charge, the antimony content accounts for 6.8% of the total antimony in the furnace charge, the lead content accounts for 3.9% of the total lead in the furnace charge, the copper content accounts for 2.7% of the total copper in the furnace charge, and the zinc content accounts for 2.1% of the total zinc in the furnace charge.

[0064] Example 2:

[0065] The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting in the present invention is as follows in detail (the arsenic-containing materials used in this example are arsenic soda residue, arsenic-antimony soot, returned arsenic soot, and arsenic sulfide slag):

[0066] 1) Material preparation: The arsenic soda residue is crushed to obtain arsenic-containing slag particles with a particle size of 20 - 25 mm and enter a special stock bin; In addition, the arsenic-antimony soot, returned arsenic soot, and arsenic sulfide slag are mixed and proportioned according to a weight ratio of 20:2:1, and then made into arsenic-containing pellets with a particle size of 10 - 25 mm and a moisture content ≤ 10% through a cylindrical pelletizer and enter a special stock bin; Prepare anthracite particles, limestone particles, and iron ore particles with a particle size of 10 - 20 mm and enter a special stock bin; The arsenic-containing pellets, arsenic-containing slag particles, anthracite particles, limestone particles, and iron ore particles are mixed and proportioned according to a weight ratio of 100:15:15:10:10 to obtain a mixed material (wherein, the arsenic-containing material contains 24.3% arsenic, 10.76% antimony, and 8.45% lead);

[0067] 2) Bath smelting: The obtained mixed material is continuously fed into an oxygen-enriched side-blowing bath smelting furnace at a feeding speed of 8 - 12 t / h, and then 85% oxygen-enriched air and natural gas are blown in for heating and high-temperature smelting (the pressures of both the oxygen-enriched air and natural gas are controlled at 0.09 - 0.12 MPa, and the blown-in gases strongly stir the high-temperature melt and participate in the reaction), adopting a quaternary slag type of FeO - SiO2 - CaO - Na2O; Control the furnace temperature at 1050 - 1100 °C and the bath depth at 1700 mm, so that the materials undergo melting, reduction, and slag formation reactions in the smelting furnace, strengthening the reduction and volatilization processes of arsenic;

[0068] 3) Charge separation: As the reaction in the smelting furnace proceeds, the melt in the furnace settles and stratifies, yielding alloy, matte, slag, and high-temperature flue gas; 2 hours after feeding, when the molten pool level approaches a depth of 1700 mm in the molten pool, slag tapping begins, and the tapped molten slag is continuously quenched with water; the produced alloy and matte are periodically discharged through the siphon port located in the hearth, once every 8 hours; most of the arsenic and some metals are volatilized and oxidized and enter the high-temperature flue gas;

[0069] 4) Flue gas treatment: The generated high-temperature flue gas is cooled by a cooling flue and a waste heat boiler, and after cooling, it is successively dust-collected by a high-temperature dust collector, cooled in a quench tower, and dust-collected in a baghouse. The obtained tail gas is treated to meet the discharge standards;

[0070] The high-temperature dust collector used is a high-temperature filtration dust collector with an intermetallic compound porous membrane as the base material. This dust collector has stronger adaptability to the complex multi-metal oxide soot generated and higher dust collection efficiency;

[0071] The flue gas temperature at the outlet of the high-temperature dust collector is controlled at 260 - 290 °C. The collected soot contains 20.5% antimony, 2.8% lead, and 27.8% arsenic on average and is returned to the furnace for treatment; the components and their contents in the crude arsenic oxide collected in the baghouse are: 2.4% antimony, 1.5% lead, and 67.5% arsenic; the total volatilization rate of arsenic is 85.5%;

[0072] The arsenic content in the crude arsenic oxide accounts for 70.3% of the total arsenic input to the furnace, the antimony content accounts for 5.6% of the total antimony input to the furnace, and the lead content accounts for 4.5% of the total lead input to the furnace.

[0073] Example 3:

[0074] The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to the present invention has the following detailed steps (the arsenic-containing materials used in this example are arsenic soot and arsenic alkali residue produced from lead smelting):

[0075] 1) Material preparation: The arsenic alkali residue is crushed to obtain arsenic-containing slag particles with a particle size of 20 - 25 mm and enter a special batching bin; in addition, the arsenic soot is made into arsenic-containing pellets with a particle size of 10 - 25 mm and a moisture content ≤ 10% by a cylindrical pelletizer and enter a special batching bin; at the same time, coke particles (used as reducing coal), limestone particles, and iron ore particles with a particle size of 10 - 20 mm are prepared and enter a special batching bin; the arsenic-containing pellets, arsenic-containing slag particles, coke particles, limestone particles, and iron ore particles are mixed and proportioned according to a weight ratio of 100:10:15:9:9 to obtain a mixed material (wherein, the arsenic-containing material contains 28.5% arsenic, 8.6% antimony, and 15.2% lead);

[0076] 2) Bath smelting: Continuously feed the obtained mixed materials into an oxygen-enriched side-blowing bath smelting furnace at a feeding speed of 6 - 10 t / h, then blow in 90% oxygen-enriched air and gas for heating and high-temperature smelting (the pressures of both the oxygen-enriched air and the gas are controlled at 0.1 - 0.13 MPa, and the blown-in gases strongly stir the high-temperature melt and participate in the reaction). Adopt the quaternary slag type of FeO - SiO2 - CaO - Na2O; control the temperature in the furnace at 1050 - 1100 °C and the bath depth at 1800 mm, so that the materials undergo melting, reduction, and slag-making reactions in the smelting furnace, strengthening the reduction and volatilization processes of arsenic;

[0077] 3) Furnace charge separation: As the reaction in the smelting furnace proceeds, the melt in the furnace settles and stratifies to obtain alloy, matte, slag, and high-temperature flue gas; 2 hours after feeding, when the bath liquid level approaches 1800 mm of the bath depth, slag is discharged. Since the discharged slag does not contain zinc, it is directly subjected to water quenching treatment; the produced alloy and matte are regularly discharged through the siphon port provided in the hearth, once every 8 hours; most of the arsenic and part of the metals are volatilized and oxidized and enter the high-temperature flue gas;

[0078] 4) Flue gas treatment: The generated high-temperature flue gas is cooled by a cooling flue and a waste heat boiler, and after cooling, it is successively dust-collected by a high-temperature dust collector, cooled by a quenching tower, and dust-collected in a bag room. The obtained tail gas is discharged up to the standard after treatment;

[0079] The high-temperature dust collector adopted is a high-temperature filtration dust collector based on an intermetallic compound porous membrane. This dust collector has stronger adaptability to the complex multi-metal oxide soot generated and higher dust collection efficiency;

[0080] The outlet flue gas temperature of the high-temperature dust collector is controlled at 260 - 290 °C. The collected soot contains on average 12.5% antimony, 5.8% lead, and 24.6% arsenic, and is sent back to the furnace for treatment; the components and their contents in the crude arsenic oxide collected in the bag room are: 2.8% antimony, 2.5% lead, and 66.3% arsenic. The total volatilization rate of arsenic is 87.2%;

[0081] The arsenic content in the crude arsenic oxide accounts for 72.5% of the total arsenic in the furnace charge, the antimony content accounts for 6.1% of the total antimony in the furnace charge, and the lead content accounts for 4.2% of the total lead in the furnace charge.

[0082] Example 4:

[0083] The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting of the present invention has the following detailed steps (the arsenic-containing materials used in this example are arsenic-containing soot and arsenic sulfide slag generated during copper and bismuth smelting):

[0084] 1) Material preparation: The arsenic-containing material prepared by mixing arsenic-containing dust and arsenic sulfide slag at a weight ratio of 25:3 is made into arsenic-containing pellets with a particle size of 10 - 25 mm and a water content of ≤10% through a cylindrical granulator and enters a special stock bin; at the same time, anthracite pellets with a particle size of 10 - 20 mm (as reducing coal), limestone pellets, and quartzite pellets are prepared and enter the special stock bin; the arsenic-containing pellets, anthracite pellets, limestone pellets, and quartzite pellets are mixed and proportioned according to a weight ratio of 100:18:12:8 to obtain a mixed material (wherein, the arsenic-containing material contains 32.0% arsenic, 5.5% antimony, 4.8% lead, 9.2% copper, and 3.0% bismuth).

[0085] 2) Bath smelting: The obtained mixed material is continuously fed into an oxygen-enriched side-blowing bath smelting furnace at a feeding speed of 7 - 11 t / h, and then 95% oxygen-enriched air and natural gas are blown in for heating and high-temperature smelting (the pressures of both the oxygen-enriched air and natural gas are controlled at 0.11 - 0.14 MPa, and the blown-in gases fully stir the high-temperature melt to promote the reaction), adopting the FeO - SiO2 - CaO ternary slag type; the temperature in the furnace is controlled at 1200 - 1250 °C and the bath depth is 2200 mm, so that the materials undergo melting, reduction, and slag-making reactions in the smelting furnace, strengthening the reduction and volatilization processes of arsenic.

[0086] 3) Furnace charge separation: As the reaction in the smelting furnace proceeds, the melt in the furnace settles and stratifies to obtain alloy, matte, slag, and high-temperature flue gas; 2 hours after feeding, when the bath liquid level approaches the bath depth of 2200 mm, slag is discharged, and the discharged slag is water-quenched; the produced alloy and matte are regularly discharged through the siphon opening provided in the hearth, 1 - 2 times every 8 hours; most of the arsenic and some metals are volatilized and oxidized and enter the high-temperature flue gas.

[0087] 4) Flue gas treatment: The generated high-temperature flue gas is cooled by a cooling flue and a waste heat boiler, and after cooling, it is dust-collected by a high-temperature dust collector, cooled by a quenching tower, and dust-collected in a bag chamber in sequence, and the obtained tail gas is discharged up to the standard after treatment;

[0088] The high-temperature dust collector adopted is a high-temperature filtration dust collector based on an intermetallic compound porous membrane, which has stronger adaptability to the complex multi-metal oxide dust generated and higher dust collection efficiency;

[0089] The flue gas temperature at the outlet of the high-temperature dust collector is controlled at 260 - 290 °C, and the collected dust contains 9.8% antimony, 2.3% copper, 3.5% lead, 1.2% bismuth, and 28.8% arsenic on average, and is returned to the furnace for treatment; the crude arsenic oxide collected in the bag chamber contains 4.8% antimony, 0.6% copper, 1.0% lead, 0.5% bismuth, and 68.5% arsenic, and the total volatilization rate of arsenic is 88.8%.

[0090] The arsenic content in the collected crude arsenic oxide accounts for 73.8% of the total arsenic charged into the furnace, the antimony content accounts for 5.2% of the total antimony charged into the furnace, the lead content accounts for 3.4% of the total lead charged into the furnace, the copper content accounts for 2.2% of the total copper charged into the furnace, and the bismuth content accounts for 2.8% of the total bismuth charged into the furnace.

Claims

1. A method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting, characterized in that, The method comprises the following steps: 1) Material preparation: Crushing massive arsenic-containing materials and granulating arsenic-containing soot to obtain arsenic-containing pellets; then proportioning the arsenic-containing pellets with fluxes and reducing coal to obtain a mixed material; 2) Bath smelting: Continuously charging the mixed material obtained by proportioning into an oxygen-enriched side-blowing bath smelting furnace, then blowing oxygen-enriched air and gaseous fuel for high-temperature smelting; controlling the temperature in the furnace to be 1000-1250 °C and the bath depth to be 1400-2400 mm, so that the materials undergo melting, reduction and slag-making reactions in the smelting furnace; 3) Furnace charge separation: As the reaction in the smelting furnace proceeds, the melt in the furnace settles and stratifies to obtain alloy, matte, slag and high-temperature flue gas; when the bath depth reaches 1400-2400 mm, the obtained slag is discharged through the slag tapping opening; the produced alloy and matte are regularly discharged through the siphon opening provided in the hearth; most of the arsenic and part of the metals are volatilized and oxidized and enter the high-temperature flue gas; 4) Flue gas treatment: The generated high-temperature flue gas is cooled by a cooling flue and a waste heat boiler, and after cooling, it is sequentially dust-collected by a high-temperature dust collector, cooled by a quenching tower, and dust-collected by a bag chamber, and the obtained tail gas is discharged up to standard after treatment.

2. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, characterized in that: In step 1), the arsenic content grades of the massive arsenic-containing materials and the arsenic-containing soot are both 1-50%.

3. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, wherein: After the massive arsenic-containing materials in step 1) are crushed, their particle size is 20-25 mm; after the arsenic-containing soot is granulated, the particle size of the obtained arsenic-containing pellets is 10-25 mm, and the moisture content ≤ 10%.

4. The method for efficiently separating arsenic from arsenic-containing materials by using oxygen-enriched side-blowing bath smelting according to claim 1, characterized in that: In step 1), the flux is at least one of iron ore, quartzite and limestone, and its particle size is 10-25 mm; the reducing coal is at least one of coke pellets and anthracite pellets, the carbon content in the reducing coal > 78%, and its particle size is 10-25 mm.

5. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, characterized in that: In step 1), the weight ratio of the arsenic-containing pellets to the reducing coal and the flux during proportioning is 100:8-20:15-30.

6. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, characterized in that: In step 2), the oxygen content concentration in the oxygen-enriched air is 25-100%, and the air pressure is 0.05-0.15 MPa; the gaseous fuel is natural gas or coal gas, and the air pressure is 0.05-0.15 MPa.

7. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, wherein: The slag obtained in step 3) is of the FeO-SiO2-CaO ternary slag type or the FeO-SiO2-CaO-Na2O quaternary slag type.

8. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, characterized in that: In step 4), the high-temperature dust collector is a high-temperature filtration dust collector based on an intermetallic compound porous membrane.

9. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, characterized in that: In step 4), the outlet flue gas temperature of the high-temperature dust collector is controlled to be 260-290 °C, and the temperature difference is controlled to be 10-20 °C.

10. The method for efficiently separating arsenic from arsenic-containing materials by oxygen-enriched side-blowing bath smelting according to claim 1, wherein: The arsenic content grade of the crude arsenic oxide collected by the bag dust collector in step 4) is 55-70%; the arsenic contained in the collected crude arsenic oxide accounts for 70-75% of the total arsenic in the furnace; the collected crude arsenic oxide contains other main metals: the antimony content accounts for 4-7% of the total antimony in the furnace, the lead content accounts for 2-4.5% of the total lead in the furnace, and the copper, bismuth and zinc contents account for 1-3% of the total metal in the furnace; the total arsenic volatilization rate reaches 80-90%.

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