Method for co-processing and removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes

Abstract

The invention belongs to the technical field of thermometallurgy, and particularly relates to a method for co-processing and removing arsenic from non-ferrous smelting arsenic-containing hazardous waste. The method for removing arsenic through co-processing of the non-ferrous smelting arsenic-containing hazardous waste comprises the following steps that different kinds of arsenic-containing hazardous waste are mixed, and a mixed material is obtained; the arsenic-containing hazardous waste comprises copper smelting arsenic-containing hazardous waste and arsenic sulfide slag, and the copper smelting arsenic-containing hazardous waste comprises copper smelting smoke dust and / or black copper sludge; the mixed material is roasted, residues and volatile matter are obtained, the volatile matter is an arsenic-containing product, and the residues are other valuable metal compounds; the roasting pressure intensity range is 1.01 * 10 < 5 > to 1.33 * 10 <-1 > Pa. According to the method provided by the invention, waste is treated by waste, and harmless and reduction treatment and resource utilization of the arsenic-containing solid waste are realized; meanwhile, the method provided by the invention is high in arsenic removal rate, short in process flow, clean, environment-friendly and suitable for industrial application.

Description

Technical Field

[0001] The invention belongs to the technical field of pyrometallurgy, and in particular relates to a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes through coordinated disposal. Background Art

[0002] Arsenic emissions during copper smelting account for more than 80% of the total emissions from non-ferrous metal smelting, of which more than 70% of arsenic is usually present in copper smelting dust obtained from the flue gas dust collection process and black copper mud produced in the electrolytic purification process of the circulating electrolyte of crude copper electrolytic refining. Arsenic sulfide slag is a hazardous waste (HW48) with an arsenic content of up to 60% produced during the treatment of polluted acid in non-ferrous smelting flue gas purification. At present, the treatment processes for copper smelting dust, black copper mud and arsenic sulfide slag mainly include wet processes. The wet process can select acid leaching and alkaline leaching according to the presence of arsenic in the raw materials. The reagents generally used are concentrated sulfuric acid and NaOH. At the same time, the addition of an oxidant can increase the arsenic leaching rate to more than 90%, and the subsequent recovery of other valuable elements such as copper, lead, and sulfur can be further realized.

[0003] Currently, most companies usually use wet leaching technology to recover or store arsenic in the form of As2O3 and arsenate. The technical process is long and the production cost is high. At the same time, a large amount of arsenic-containing wastewater will be generated, posing a major safety hazard. Summary of the invention

[0004] The purpose of the present invention is to provide a method for the coordinated disposal of arsenic-containing hazardous waste from non-ferrous smelting to remove arsenic. The method provided by the present invention treats waste with waste, achieves the harmless and reduced treatment of arsenic-containing solid waste and resource utilization; at the same time, the method provided by the present invention has a high arsenic removal rate, a short process flow, and is clean and environmentally friendly, and is suitable for industrial application.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous waste by co-disposal, comprising the following steps:

[0007] Mixing arsenic-containing hazardous wastes to obtain a mixed material, wherein the arsenic-containing hazardous wastes include copper smelting arsenic-containing hazardous wastes and arsenic sulfide slag, and the copper smelting arsenic-containing hazardous wastes include copper smelting smoke and / or black copper mud;

[0008] The mixed material is roasted to obtain a residue and a volatile, wherein the volatile is an arsenic-containing product and the residue is other valuable metal compounds; the roasting pressure range is 1.01×10 5 ~1.33×10 -1 Pa.

[0009] Preferably, the main components of the copper smelting fume include: As 12-18%, Zn 14-20%, Pb10-15%, Bi 4-6%, Cu 3-4%, Fe 4-6% and Sn 0.5-1.5%; the main phases of the copper smelting fume include PbSO4, Zn(H2O)(OH)(AsO3), As2O3, As2O5, ZnSO4(H2O), Bi2O3 and SnO2.

[0010] Preferably, the main components of the black copper mud include: Cu 30-35%, As 20-35%, S 5-8%, Sb0.5-1.5% and Ni 0.5-1%; the main phases of the black copper mud include As2O3, CuSO4·H2O, Cu5As2 and Cu3As.

[0011] Preferably, the main components of the arsenic sulfide slag include As 20-40%, S 30-50%, Cd 2-3%, Na2.5-4% and Pb 1-2.5%; the main phases of the arsenic sulfide slag include As2O3, As2S3, S, and PbSO4, and the As2S3 in the arsenic sulfide slag is in an amorphous state.

[0012] Preferably, the mass ratio of the copper smelting fume to the arsenic sulfide slag is 1:(0.5-4);

[0013] The mass ratio of the black copper mud to the arsenic sulfide slag is 1:(0.3-4).

[0014] Preferably, the calcination temperature is 400-800° C., and the calcination holding time is ≥20 min.

[0015] Preferably, the heating rate from room temperature to the calcination temperature is 5-16° C. / min.

[0016] Preferably, the arsenic-containing product includes one or more of arsenic oxides, arsenic sulfides and elemental arsenic.

[0017] Preferably, the other valuable metal compounds include one or more of copper sulfide, lead sulfide and zinc oxide.

[0018] Preferably, before the mixing, the method further comprises: pre-treating the copper smelting arsenic-containing hazardous waste and arsenic sulfide slag respectively, wherein the pre-treatment comprises drying, grinding and screening;

[0019] The drying temperature is 105-300°C and the drying time is 5-24h;

[0020] The separation sieve used in the screening is an 80-mesh sieve or a 100-mesh sieve.

[0021] The present invention provides a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes by co-disposal, comprising the following steps: mixing arsenic-containing hazardous wastes to obtain a mixed material, wherein the arsenic-containing hazardous wastes include copper smelting arsenic-containing hazardous wastes and arsenic sulfide slag, and the copper smelting arsenic-containing hazardous wastes include copper smelting smoke and / or black copper mud; roasting the mixed material to obtain residues and volatiles, wherein the volatiles are arsenic-containing products, and the residues are other valuable metal compounds; the roasting pressure range is 1.01×10 5 ~1.33×10 -1 Pa. The present invention uses different arsenic-containing hazardous wastes generated by the metallurgical industry, such as arsenic sulfide slag, mixed with copper smelting smoke and / or black copper mud, and then roasted. During the roasting process, the arsenic sulfide slag reacts with the stable arsenic-containing compounds in the copper smelting arsenic-containing hazardous waste (copper smelting smoke, black copper mud), and the components in the copper smelting arsenic-containing hazardous waste (black copper mud) react with each other to generate easily volatile arsenic-containing products and release toxic element arsenic; the residue obtained is other valuable metal compounds. At the same time, the pressure range of the present invention to control the roasting is 1.01×10 5 ~1.33×10 -1 Pa can significantly increase the evaporation rate of volatile arsenic-containing products, while valuable metals are enriched in the residues, thereby achieving effective separation of toxic element arsenic and other valuable metals. The method provided by the present invention not only has a simple process flow and high arsenic removal efficiency, but is also suitable for the coordinated disposal of arsenic-containing hazardous wastes and arsenic sulfide slag, and has a good working environment, is clean and efficient, and does not produce secondary pollution. Valuable metals are enriched in the residues, which can further achieve the selective recovery and recycling of valuable metals in arsenic-containing materials, and comprehensively improve resource utilization efficiency. The results of the embodiment show that the method provided by the present invention can be used to remove arsenic from common arsenic-containing materials (copper smoke, black copper mud and arsenic sulfide slag) in non-ferrous smelting, and the arsenic removal rate reaches more than 95%. In summary, the method provided by the present invention treats waste with waste, realizes the harmless and reduced treatment of arsenic-containing solid waste and resource utilization; at the same time, the method provided by the present invention has a high arsenic removal rate, a short process flow, and is clean and environmentally friendly, suitable for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A process flow chart of the method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes in a coordinated manner provided by the present invention;

[0023] Figure 2 The X-ray diffraction pattern of the arsenic sulfide slag raw material used in the embodiment of the present invention;

[0024] Figure 3 The X-ray diffraction pattern of the black copper mud raw material used in the embodiment of the present invention;

[0025] Figure 4The X-ray diffraction pattern of the copper fume raw material used in the embodiment of the present invention;

[0026] Figure 5 is the X-ray diffraction pattern of the condensate obtained in Example 1 of the present invention;

[0027] Figure 6 is the X-ray diffraction pattern of the residue obtained in Example 1 of the present invention;

[0028] Figure 7 This is the X-ray diffraction pattern of the residue obtained in Example 3 of the present invention. DETAILED DESCRIPTION

[0029] The present invention provides a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous waste by co-disposal, comprising the following steps:

[0030] Mixing arsenic-containing hazardous wastes to obtain a mixed material, wherein the arsenic-containing hazardous wastes include copper smelting arsenic-containing hazardous wastes and arsenic sulfide slag, and the copper smelting arsenic-containing hazardous wastes include copper smelting smoke and / or black copper mud;

[0031] The mixed material is roasted to obtain a residue and a volatile, wherein the volatile is an arsenic-containing product and the residue is other valuable metal compounds; the roasting pressure range is 1.01×10 5 (i.e. normal pressure)~1.33×10 -1 Pa.

[0032] In the present invention, unless otherwise specified, all preparation raw materials / components are commercially available products well known to those skilled in the art.

[0033] The method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes provided by the present invention has a short process flow, and the arsenic removal rate is maintained at above 90%, thereby achieving the harmless and reduced treatment of arsenic-containing hazardous wastes (copper smelting smoke, black copper mud and arsenic sulfide slag), and is clean and environmentally friendly.

[0034] The present invention mixes arsenic-containing hazardous wastes to obtain a mixed material, wherein the arsenic-containing hazardous wastes include copper smelting arsenic-containing hazardous wastes and arsenic sulfide slag, and the copper smelting arsenic-containing hazardous wastes include copper smelting smoke and / or black copper mud. In the present invention, the main components of the copper smelting smoke preferably include: As 12-18%, Zn 14-20%, Pb 10-15%, Bi 4-6%, Cu 3-4%, Fe 4-6% and Sn 0.5-1.5%. The main phase of the copper smelting smoke preferably includes PbSO4, Zn(H2O)(OH)(AsO3), As2O3, As2O5, ZnSO4(H2O), Bi2O3 and SnO2. The main components of the black copper mud preferably include: Cu 30-35%, As 20-35%, S 5-8%, Sb 0.5-1.5% and Ni 0.5-1%. The main phase of the black copper mud preferably includes As2O3, CuSO4·H2O, Cu5As2 and Cu3As. The main components of the arsenic sulfide slag preferably include As20-40%, S 30-50%, Cd 2-3%, Na 2.5-4% and Pb 1-2.5%. The main phase of the arsenic sulfide slag preferably includes As2O3, As2S3, S, and PbSO4, and As2S3 in the arsenic sulfide slag is preferably amorphous.

[0035] In the present invention, the mass ratio of the copper smelting smoke and the arsenic sulfide slag is preferably 1: (0.5-4), more preferably 1: (1-3), and in the embodiment it can be 1: 2 or 1: 1. The mass ratio of the black copper mud and the arsenic sulfide slag is preferably 1: (0.3-4), more preferably 1: (0.5-4), further preferably 1: (1-2), and in the embodiment it can be 1: 4, 1: 0.8 or 1: 1. When the arsenic-containing hazardous waste includes copper smelting smoke and black copper mud, when calculating the amount of arsenic sulfide slag in the present invention, the mass ratio of copper smelting smoke and the arsenic sulfide slag and the mass ratio of black copper mud and the arsenic sulfide slag are calculated respectively and then summed.

[0036] In the present invention, before the mixing, the present invention preferably further comprises: pre-treating the copper smelting arsenic-containing hazardous waste and arsenic sulfide slag respectively, and the pre-treatment comprises drying, grinding and screening. In the present invention, the drying temperature is preferably 105-300°C, and the time is preferably 5-24h. In the present invention, the drying temperature of the copper smelting fume is more preferably 200-300°C, and the time is preferably 5-24h, more preferably 8-20h, and more preferably 9-12h. The drying temperature of the black copper mud is preferably 105-200°C, more preferably 110-180°C, and more preferably 120-150°C; the time is preferably 5-24h, more preferably 8-20h, and more preferably 9-12h. The drying temperature of the arsenic sulfide slag is preferably 105-200°C, more preferably 110-180°C, and more preferably 120-150°C; the time is preferably 5-24h, more preferably 8-20h, and more preferably 9-12h. The grinding is preferably carried out in a pulverizer or in a mortar. The present invention has no special requirements for the specific implementation of the grinding. The separation screen used for the screening is preferably an 80-mesh screen or a 100-mesh screen, and the material of the separation screen is specifically stainless steel. The screening takes the undersize.

[0037] In the present invention, the grinding, sieving and drying are preferably carried out in the following order: grinding, sieving and drying in sequence, or drying, grinding and sieving in sequence.

[0038] The present invention has no special requirements on the specific implementation method of the mixing of arsenic-containing hazardous wastes.

[0039] After obtaining the mixed material, the present invention roasts the mixed material to obtain a residue and a volatile, wherein the volatile is an arsenic-containing product and the residue is other valuable metal compounds; the roasting pressure range is 1.01×10 5 ~1.33×10 -1 Pa. In the present invention, the calcination is preferably carried out in a tube furnace, and the tube furnace is specifically a vacuum tube furnace or a tube resistance furnace. Before the calcination, the tube furnace can be connected to a gas purification device. In a specific embodiment of the present invention, the calcination is carried out in a vacuum environment, or in a semi-open state. When the calcination is carried out in a semi-open state, the pressure of the calcination is normal pressure (1.01×10 5 Pa), the material can be in contact with air. In the present invention, when the calcination is carried out in a vacuum environment, it is called vacuum calcination. The present invention preferably performs vacuum calcination in an inert gas atmosphere, and the inert gas is preferably argon. The implementation method of the vacuum calcination preferably includes: firstly connecting the vacuum calcination device to a vacuum reaction system, and then passing an inert gas at one end of the vacuum calcination device to adjust the pressure of the vacuum calcination device; the inert gas is preferably argon.

[0040] In the present invention, the calcination pressure is 1.01×10 5 Pa~1.33×10 -1 Pa, preferably 1 to 50000 Pa, more preferably 1 to 1000 Pa, in the embodiment, it can be 1 Pa, normal pressure (1.01×10 5 When the calcination is carried out in a vacuum environment, the pressure of the calcination is preferably adjusted by connecting the vacuum tube furnace to a vacuum reaction system, and then passing an inert gas at one end of the vacuum tube furnace to adjust the pressure of the vacuum tube furnace; the inert gas is preferably argon.

[0041] In the present invention, the calcination temperature is preferably 500-800°C, more preferably 550-700°C, further preferably 600-700°C, and in the embodiment it can be 700°C, 600°C or 650°C. The calcination holding time is preferably ≥20min, more preferably ≥30min, further preferably 30-120min, most preferably 60-100min, and in the embodiment it can be 120min, 100min, 60min or 3h. The heating rate from room temperature to the calcination temperature is preferably 5-16°C / min, more preferably 10-15°C / min, further preferably 11-14°C / min, most preferably 12-13°C / min, and in the embodiment it can be 13°C / min, 12°C / min, 10°C / min or 14°C / min. The present invention uses the principle of metal-sulfur strong bonding to react elemental sulfur and sulfide in arsenic sulfide slag with stable arsenic compounds in arsenic-containing hazardous waste (copper smelting smoke and / or black copper mud) through roasting, and converts them into arsenic oxides, arsenic sulfides and elemental arsenic with large saturated vapor pressure, and volatilizes to obtain volatiles. The present invention preferably allows the volatiles to enter the low temperature zone of the vacuum tube furnace for condensation, and the condensation temperature is preferably 50 to 300° C. The arsenic-containing product obtained by condensation preferably includes one or more of arsenic oxides, arsenic sulfides and elemental arsenic, and the main phase of the arsenic-containing product is preferably As2O3 and As4S4.

[0042] In the present invention, the main reactions that may occur during the calcination include the following:

[0043] (1)Cu3As+3 / 4S2(g)=3 / (2-x)Cu 2-x S+1 / 4As4(g);

[0044] (2)Cu5As2+5 / 4S2(g)=5 / (2-x)Cu 2-x S+1 / 2As4(g);

[0045] (3)Cu3As+As2S3(g)=3CuS+3 / 4As4(g);

[0046] (4)Cu3As+3 / 4CuSO4=15 / 4Cu+1 / 4As4O6(g)+3 / 4SO2(g);

[0047] (5)As4(g)+2S2(g)=As4S4(g);

[0048] (6)As4O6(g)+7 / 2S2(g)=As4S4(g)+3SO2(g);

[0049] (7)Me3(AsO4)2+11 / 4S2(g)=3MeS+1 / 2As4O6(g)+5 / 2SO2(g);

[0050] (8)Me3(AsO4)2+11 / 9As2S3(g)→3MeS+10 / 9As4O6(g)+2 / 3SO2(g);

[0051] (9)Bi2O3+3 / 4S2(g)=2Bi+3 / 2SO2(g);

[0052] (10)PbSO4+S2(g)=PbS+2SO2(g);

[0053] (11)PbSO4+4 / 9As2S3(g)=PbS+2 / 9As4O6(g)+4 / 3SO2(g).

[0054] In the present invention, during the roasting process, valuable metals such as copper, lead and zinc in the arsenic sulfide slag and arsenic-containing hazardous waste are enriched in the residue after arsenic removal, and the toxic element arsenic evaporates in the form of gas under the high temperature conditions of roasting, condenses and collects in the low temperature zone, so as to achieve the selective separation of arsenic. The residue after the enrichment of valuable metals is reduced in volume and low in toxicity, and can be directly returned to the main process of non-ferrous smelting for recycling. In the present invention, the other valuable metal compounds include one or more of copper sulfide, lead sulfide and zinc oxide. In the present invention, after the roasting is completed, the present invention will preferably cool the roasting residue to ≤150°C and then take it out.

[0055] In the present invention, the SO2 flue gas generated during the roasting process preferably enters an acid-making system to produce sulfuric acid.

[0056] The method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes provided by the present invention preferably comprises the following steps: fully mixing the arsenic-containing hazardous wastes with arsenic sulfide slag and then roasting them; the roasting process is carried out at 1.01×10 5 ~1.33×10 -1Pa conditions. The present invention utilizes the mutual reaction between the components in arsenic sulfide slag and arsenic-containing hazardous waste, and achieves the separation of arsenic and other valuable metals by roasting at 400°C to 800°C. The method provided by the present invention has a simple process and strong operability, and can achieve low-toxicity and reduced-volume disposal of arsenic-containing hazardous waste, thereby improving the recycling level of the non-ferrous smelting industry. By using the method provided by the present invention to dispose of arsenic-containing hazardous waste and arsenic sulfide slag, the comprehensive arsenic removal rate can reach more than 90%.

[0057] In order to further illustrate the present invention, the technical solutions provided by the present invention are described in detail below in conjunction with embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0058] The following embodiment provides a flowchart of a method for removing arsenic from non-ferrous metallurgical arsenic-containing hazardous wastes in a coordinated manner. Figure 1 shown.

[0059] Example 1

[0060] This embodiment provides a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes by collaborative disposal, which specifically includes the following steps:

[0061] Take arsenic sulfide slag and black copper mud, dry them at 120℃ for 10h, grind them in a pulverizer, and finally sieve them through a 100-mesh stainless steel sieve. Weigh 10g of arsenic sulfide slag and 10g of black copper mud sieve respectively, mix them evenly and place them in a corundum crucible, place the crucible in a quartz tube in a vacuum tube furnace, connect the vacuum reaction system, then pass argon gas at one end of the vacuum tube furnace, turn on the vacuum pump, evacuate the vacuum tube furnace, adjust the pressure of the vacuum tube furnace, and when the residual pressure in the reaction device reaches 1Pa, control the roasting temperature to 600℃, the heating rate to 14℃ / min, heat from room temperature to the roasting temperature of 600℃, keep warm for 120min at 600℃, cool naturally after the reaction, and obtain a large amount of yellow and orange condensates in the low temperature zone. When the temperature in the furnace drops below 150℃, take out the crucible, and use X-ray fluorescence spectroscopy to test the residue in the crucible to contain 9.13% As and 9.13% Cu. 35.86%, S18.51%, weight loss rate was 54.45%, arsenic volatilization rate reached 91.12%, and copper direct recovery rate was 97.9%, wherein direct recovery rate refers to the element component content in the residue / initial raw material component content.

[0062] Example 2

[0063] This embodiment provides a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes by collaborative disposal, which specifically includes the following steps:

[0064] The black copper mud and arsenic sulfide slag were dried at 150℃ for 5h, ground with a mortar and sieved with a 100-mesh stainless steel sieve. Weigh 10g of black copper mud and 8g of arsenic sulfide slag sieve respectively, mix them evenly and place them in a crucible. The crucible was placed in the heating center of the quartz tube in the tubular resistance furnace. One end of the quartz tube was closed and the other end was connected to the gas purification device. The temperature was adjusted to 650℃, and the heating rate was controlled at 10℃ / min. The temperature was raised to 650℃ and the pressure (1.01×10 5 Pa) for 100 min, and then cool naturally after the reaction. A large amount of yellow and white condensate is obtained in the low temperature zone. When the temperature in the furnace drops below 150°C, the crucible is taken out. The residue in the crucible contains 9.51% As, 36.99% Cu, 19.15% S, and a weight loss rate of 53.05%. The arsenic volatilization rate reaches 90.07%, the direct recovery rate is greater than 99%, and there is basically no loss of copper.

[0065] Example 3

[0066] This embodiment provides a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous wastes by collaborative disposal, which specifically includes the following steps:

[0067] The copper smelting fume was placed in an electric blast drying oven at 260°C for 8 hours, and the arsenic sulfide slag was placed in an electric blast drying oven at 105°C for 8 hours. The dried copper smelting fume and arsenic sulfide slag were ground in a pulverizer and sieved through a 100-mesh stainless steel sieve. Then 10g of the arsenic sulfide slag and copper smelting fume were weighed, mixed evenly, and placed in a corundum crucible. The crucible was placed in a vacuum tube furnace, and the vacuum reaction system was connected. Then argon gas was passed through one end of the vacuum tube furnace, and the vacuum pump was turned on to evacuate the vacuum tube furnace. The pressure in the vacuum tube furnace was adjusted. When the residual pressure in the reaction device was evacuated to 80Pa, the roasting temperature was adjusted to 600°C, the heating rate was controlled at 12°C / min, and the temperature was kept for 60 minutes. After the reaction was completed, it was naturally cooled. When the temperature in the furnace drops below 150°C, the crucible is taken out. The residue in the crucible contains 3.05% As, 6.12% Cu, 20.07% Zn, and 14.17% S. The weight loss rate is 57.4%, the arsenic volatilization rate reaches 94.39%, the direct recovery rate of copper is >99%, and there is basically no loss of copper.

[0068] Example 4

[0069] The arsenic sulfide slag was dried at 110°C for 24 hours, the black copper mud was dried at 150°C for 10 hours, and the copper smelting smoke was dried at 200°C for 12 hours. Then, the arsenic sulfide slag, black copper mud and copper smelting smoke were ground by a pulverizer and sieved through a 100-mesh stainless steel sieve. 40g of the arsenic sulfide slag undersize, 5g of the black copper mud undersize and 20g of the copper smelting smoke undersize were weighed respectively. The mass ratio of copper smelting smoke and arsenic sulfide slag was 1:2, and the mass ratio of black copper mud and arsenic sulfide slag was 1:4. The three materials were mixed evenly and placed in a porcelain boat. The porcelain boat was placed in a vacuum tube furnace, and the vacuum reaction system was connected. Then, argon gas was passed through one end of the vacuum tube furnace, and the vacuum pump was turned on to evacuate the vacuum tube furnace. The pressure in the vacuum tube furnace was adjusted. When the residual pressure in the vacuum tube furnace was stabilized at 20000Pa, the roasting temperature was adjusted to 700℃, the heating rate was controlled at 13℃ / min, and the temperature was kept for 3h. After the reaction was completed, it was naturally cooled. When the temperature in the furnace dropped below 150℃, the crucible was taken out. The residue in the crucible contained 2.48% As and 2.67% Cu. 7.87%, Zn 15.43%, S16.83%, weight loss rate is 61.50%, arsenic volatilization rate reaches 98.47%, and copper direct recovery rate is 98.78%.

[0070] Figure 1 The present invention provides a process flow chart of a method for removing arsenic from non-ferrous smelting arsenic-containing hazardous waste by co-disposal. The present invention first mixes the arsenic-containing hazardous waste with arsenic sulfide slag, and then 5 ~1.33×10 -1 Pa, and calcined to obtain volatile arsenic-containing products and residues enriched in valuable metals such as Cu, Zn, and Pb, thereby achieving the selective separation of the toxic element arsenic.

[0071] The arsenic sulfide slag raw material and the black copper mud raw material used in Example 1 of the present invention were tested by X-ray diffraction, and the following results were obtained: Figure 2 and Figure 3 The X-ray diffraction pattern is shown. Figure 2 It can be seen that the main phases of the arsenic sulfide slag raw material used in Example 1 of the present invention are S8, As2O3 and PbSO4. Figure 3 It can be seen that the main phases of the black copper mud raw material used in Example 1 of the present invention are As2O3, CuSO4·H2O, Cu5As2 and Cu3As. The XRD spectra of the arsenic sulfide slag raw material and the black copper mud raw material used in Example 2 are the same as those in Example 1. The XRD spectra of the arsenic sulfide slag raw material used in Example 3 are the same as those in Example 1.

[0072] The XRD spectra of the arsenic sulfide slag raw material and the black copper mud raw material used in Example 4 are the same as those in Example 1.

[0073] The copper smelting smoke raw material used in Example 3 of the present invention was tested by X-ray diffraction using an X-ray diffractometer to obtain Figure 4 The X-ray diffraction pattern is shown. Figure 4 It can be seen that the main phases of the copper smelting dust raw material used in Example 3 of the present invention are PbSO4, Zn(H2O)(OH)(AsO3), As2O3, ZnSO4(H2O), Bi2O3 and SnO2. The XRD spectrum of the copper smelting dust raw material used in Example 4 is the same as that in Example 3.

[0074] The condensate and the residue obtained in Example 1 of the present invention were analyzed by X-ray diffraction using an X-ray diffractometer. The results are as follows: Figure 5 and Figure 6 The X-ray diffraction pattern is shown in . Figure 5 and Figure 6 It can be seen that the main components of the condensate obtained in Example 1 of the present invention are As2O3 and As4S4, and the main components of the residue are CuS, Cu 7.2 S4 achieves efficient separation of arsenic and other valuable metals.

[0075] The residue obtained in Example 3 of the present invention was subjected to X-ray diffraction analysis using an X-ray diffractometer. The results are as follows: Figure 7 The X-ray diffraction pattern is shown in . Figure 7 It can be seen that the main components of the residue obtained in Example 3 of the present invention are PbS, SnO2, Bi and Bi2O3, which shows that arsenic and other valuable metals are successfully separated.

[0076] It can be seen from the above embodiments that the method for removing arsenic from non-ferrous smelting arsenic-containing hazardous waste coordinated disposal provided by the present invention not only has a simple process flow but also has high efficiency. The arsenic removal rate can reach as high as over 98%, and the arsenic content in the residue is reduced to below 3% without generating secondary pollution. Valuable metals are enriched in the residue and can be directly returned to the main process of non-ferrous smelting for recovery.

[0077] Comparative Example 1

[0078] The ground copper smelting dust was placed in an electric blast drying oven at 240°C for 4 hours, and 100g of the dried copper smelting dust was weighed and placed in a vacuum reactor for roasting. First, the vacuum reactor was connected to the vacuum reaction system, and then argon was passed through one end of the vacuum tube furnace, and the vacuum pump was turned on to evacuate the vacuum tube furnace, and the pressure of the vacuum tube furnace was adjusted. When the residual pressure in the vacuum reactor was evacuated to 10Pa, the roasting temperature was adjusted to 700°C, the heating rate was controlled to 14°C / min, and the temperature was kept for 5 hours. After the reaction was completed, the reactor was taken out when the temperature in the furnace dropped below 100°C, and the residue obtained contained 16.07% As, 4.52% Cu, 19.17% Zn, and 3.24% S, with a weight loss rate of 6.22%, an arsenic volatilization rate of only 1%, and a direct recovery rate of copper of 95.76%.

[0079] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for removing arsenic from non-ferrous smelting arsenic-containing hazardous waste by collaborative disposal, characterized in that: The following steps are involved: Mixing arsenic-containing hazardous wastes to obtain a mixed material, wherein the arsenic-containing hazardous wastes include copper smelting arsenic-containing hazardous wastes and arsenic sulfide slag, and the copper smelting arsenic-containing hazardous wastes include copper smelting smoke and / or black copper mud; The mixed material is roasted to obtain a residue and a volatile, wherein the volatile is an arsenic-containing product and the residue is other valuable metal compounds; the roasting pressure range is 1.01×10 5 ~1.33×10 -1 Pa.

2. The method according to claim 1, characterized in that The main components of the copper smelting fume include: As 12-18%, Zn 14-20%, Pb 10-15%, Bi 4-6%, Cu 3-4%, Fe 4-6% and Sn 0.5-1.5%; the main phases of the copper smelting fume include PbSO4, Zn(H2O)(OH)(AsO3), As2O3, As2O5, ZnSO4(H2O), Bi2O3 and SnO2.

3. The method according to claim 1, characterized in that The main components of the black copper mud include: 30-35% Cu, 20-35% As, 5-8% S, 0.5-1.5% Sb and 0.5-1% Ni; the main phases of the black copper mud include As2O3, CuSO4·H2O, Cu5As2 and Cu3As.

4. The method according to claim 1, characterized in that: The main components of the arsenic sulfide slag include As 20-40%, S 30-50%, Cd 2-3%, Na 2.5-4% and Pb 1-2.5%; the main phases of the arsenic sulfide slag include As2O3, As2S3, S, and PbSO4, and the As2S3 in the arsenic sulfide slag is in an amorphous state.

5. The method according to any one of claims 1 to 4, characterized in that: The mass ratio of the copper smelting dust to the arsenic sulfide slag is 1:(0.5-4); The mass ratio of the black copper mud to the arsenic sulfide slag is 1:(0.3-4).

6. The method according to claim 1, characterized in that The calcination temperature is 400-800° C., and the calcination insulation time is ≥20 min.

7. The method according to claim 1 or 6, characterized in that: The heating rate from room temperature to the calcination temperature is 5 to 16° C. / min.

8. The method according to claim 1, characterized in that The arsenic-containing product includes one or more of arsenic oxides, arsenic sulfides and elemental arsenic.

9. The method according to claim 1, characterized in that: The other valuable metal compounds include one or more of copper sulfide, lead sulfide and zinc oxide.

10. The method according to claim 1, characterized in that Before the mixing, the method further includes: pre-treating the copper smelting arsenic-containing hazardous waste and the arsenic sulfide slag respectively, wherein the pre-treatment includes drying, grinding and screening; The drying temperature is 105-300°C and the drying time is 5-24h; The separation sieve used in the screening is an 80-mesh sieve or a 100-mesh sieve.

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