A method for recovering antimony, lead and precious metals by sulfidation reduction smelting of arsenic-free lead anode mud

Abstract

The present invention relates to a method for recovering antimony, lead and precious metals by sulfurization reduction smelting of dearsenicized lead anode mud. The method specifically comprises the following steps: grinding dearsenicized lead anode mud, reducing agent, sulfurizing agent and slag-forming agent to a certain particle size and mixing them in a certain proportion; sending the mixture into a reduction smelting furnace for reduction smelting, controlling the smelting temperature and smelting time, generating lead-antimony alloy and capturing precious metals; the reducing agent is at least one of coke, coal powder, natural gas or blue coke; the sulfurizing agent is at least one of lead sulfide, zinc sulfide or arsenic sulfide; and the slag-forming agent is at least one of sodium carbonate or sodium hydroxide. Compared with the prior art, the present invention makes full use of the strong binding ability of the sulfur component in the sulfurizing agent with the sodium component in the dearsenicized lead anode mud, performs directional transformation of the sodium lead acid and sodium antimonate phases, improves the reduction activity of lead and antimony, and then realizes the efficient recovery of antimony, lead and precious metals in the dearsenicized lead anode mud, and at the same time has the advantages of short process and low cost, and has good prospects for promotion and application.

Description

Technical Field

[0001] The invention belongs to the technical field of hazardous waste resource disposal, and relates to a method for recovering antimony, lead and precious metals by sulfidation reduction smelting of arsenic-free lead anode mud. Background Art

[0002] Lead anode mud is a material produced during the lead electrolytic refining process. It contains high levels of toxic elements such as arsenic and lead. When stored in the environment, it poses a great threat to the environment and poses a great safety risk. At the same time, it contains a large amount of valuable metals such as antimony, bismuth, lead and tin, and contains rare and precious metals such as gold and silver, and has great resource recovery value. Domestic and foreign researchers and non-ferrous metal smelting companies have conducted a lot of research to achieve the resource utilization and harmless disposal of lead anode mud.

[0003] At present, there are two main treatment methods for lead anode mud: pyrometallurgical treatment process and hydrometallurgical-pyrometallurgical combined process. Traditional pyrometallurgical process generally uses direct reduction smelting method to recover antimony, lead and precious metal resources. However, the degree of dispersion of toxic elements arsenic and lead is serious during the treatment process, which is easy to cause secondary pollution, and there are problems such as long production cycle and high energy consumption.

[0004] Patent CN103397191A discloses a method for comprehensively and efficiently treating lead anode mud using a top-blown furnace, including the steps of preparing a mixed material, primary reduction smelting, reduction and gold capture, secondary blowing, and recovery of arsenic and antimony, that is, evenly mixing dry weight lead anode mud, slag-making agent, return material, and reducing agent to obtain a mixed material; spraying 1-10% of the fuel by weight into the top-blown furnace molten pool, controlling the smelting temperature of the top-blown furnace to be 900-1200°C, floating up to form a slag layer after sufficient reaction, and then discharged through a discharge port for recycling; the lead reduced by the reducing agent captures gold and silver and then sinks to form a precious lead layer, which is further intensively blown and discharged through a discharge port for further refining; the high-temperature smoke is passed through a waste heat recovery device, cooled and dusted to obtain arsenic-antimony smoke. However, during the implementation of the patent, arsenic in the reduction smelting process is widely dispersed in arsenic-antimony smoke, smelting slag and lead-antimony alloy, with a large dispersion, and secondary arsenic pollution is difficult to control; the wet-fire combined process generally first uses oxygen pressure alkali leaching to pre-de-arsenify lead anode mud, and controls key parameters such as oxygen pressure, leaching temperature and alkali concentration during the process, and then combines the leached slag with the reduction smelting method to achieve the recovery of antimony, lead and precious metal resources, effectively avoiding the dispersion of arsenic. However, due to the use of oxygen pressure alkali leaching process in the early stage of this method, the lead and antimony phases are partially transformed into sodium lead acid and sodium antimonate, and the reduction of the two is difficult, resulting in a high content of lead and antimony in the slag during the reduction smelting process, generally around 5-20wt.%, resulting in serious loss of lead and antimony resources, and further resulting in a decrease in the recovery rate of precious metal resources. Therefore, how to achieve the effective recovery of antimony, lead and precious metal resources in de-arsenicized lead anode mud has become a problem of great concern in the non-ferrous metal smelting industry. Summary of the invention

[0005] The purpose of the present invention is to provide a method for recovering antimony, lead and precious metals by sulfiding reduction smelting of dearsenicized lead anode mud in order to overcome at least one defect of the above-mentioned prior art. The present invention makes full use of the strong binding ability of the sulfur component in the sulfiding agent and the sodium component in the dearsenicized lead anode mud, and carries out directional conversion of the sodium lead acid and sodium antimonate phases, thereby improving the reduction activity of the lead and antimony phases, and then realizing the efficient recovery of antimony, lead and precious metals in the dearsenicized lead anode mud.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] One of the technical solutions of the present invention is to provide a method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud, the method comprising the following steps:

[0008] (1) grinding the dearsenicized lead anode mud, reducing agent, sulfiding agent and slag-forming agent to a certain particle size and uniformly mixing them in a certain proportion;

[0009] (2) The mixture is fed into a reduction smelting furnace for reduction smelting, and key parameters such as smelting temperature and smelting time are controlled. During the smelting process, the sulfiding agent undergoes a sulfidation replacement reaction with the sodium lead oxide and sodium antimonate phases in the dearsenicized lead anode mud, thereby increasing the reduction activity of the lead and antimony phases. The lead and antimony phases undergo a reduction reaction to generate a lead-antimony alloy, and then the precious metals such as gold and silver therein are captured, thereby achieving efficient recovery of antimony, lead and precious metals.

[0010] As a preferred technical solution, the lead-antimony alloy generated during the smelting process flows out through the molten metal outlet, the produced slag is discharged through the slag outlet, and the generated flue gas is discharged into the atmosphere after waste heat recovery and flue gas treatment meet the standards.

[0011] Furthermore, in step (1), the antimony content of the dearsenicized lead anode mud is 1-50wt.%, the lead content is 1-50wt.%, the gold content is 0.03-0.8kg / t, and the silver content is 10-150kg / t.

[0012] Furthermore, in step (1), the reducing agent is at least one of coke, coal powder, natural gas or lignite.

[0013] Furthermore, the amount of reducing agent added in step (1) is 1-25wt.% of the dearsenicized lead anode mud.

[0014] Furthermore, in step (1), the sulfiding agent is at least one of lead sulfide, zinc sulfide or arsenic sulfide.

[0015] Furthermore, in step (1), the amount of the sulfiding agent added is 1-15 wt.% of the dearsenicized lead anode mud.

[0016] Furthermore, in step (1), the slag-forming agent is at least one of sodium carbonate or sodium hydroxide.

[0017] Furthermore, the amount of slag-forming agent added in step (1) is 5-35wt.% of the dearsenicized lead anode mud.

[0018] Furthermore, in step (1), the grinding particle size of the dearsenicized lead anode mud, reducing agent, sulfiding agent and slag forming agent is 20-300 mesh.

[0019] Furthermore, in step (2), the smelting temperature is 800-1100° C., and the smelting time is 30-180 min.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) The sulfiding agent of the present invention can undergo a sulfidation replacement reaction with the sodium lead acid and sodium antimonate phases in the dearsenicized lead anode mud, thereby improving the reduction activity and reduction recovery rate of the lead and antimony phases, and generating a lead-antimony alloy to efficiently capture the precious metals such as gold and silver therein, thereby comprehensively realizing the efficient recovery of antimony, lead and precious metals in the dearsenicized lead anode mud;

[0022] (2) The present invention has a short process and low cost, and can be directly grafted into the existing reduction smelting process, and has a good prospect for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The present invention is a process flow chart of a method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The present invention is described in detail below in conjunction with specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0025] Unless otherwise specified, the equipment used in the following examples are all conventional equipment in the art; the reagents used are all commercially available products or prepared by conventional methods in the art unless otherwise specified. Anything not described in detail in the following examples can be achieved by conventional experimental means in the art.

[0026] A method for recovering antimony, lead and precious metals by sulfidation reduction smelting of arsenic-free lead anode mud, such as Figure 1 As shown, the specific steps are as follows:

[0027] Dearsenicized lead anode mud (lead content of 1-50wt.%, antimony content of 1-50wt.%, gold content of 0.03-0.8kg / t, silver content of 10-150kg / t), reducing agent (at least one of coke, coal powder, natural gas or semi-coke, added in an amount of 1-25wt.% of the dearsenicized lead anode mud), sulfiding agent (at least one of lead sulfide, zinc sulfide or arsenic sulfide, added in an amount of 1-15wt.% of the dearsenicized lead anode mud) and slag forming agent (sodium carbonate or hydrogen sulfide) are prepared. At least one of sodium oxide, the addition amount is 5-35wt.% of the dearsenicized lead anode mud), are all ground to 20-300 mesh and evenly mixed, and then sent to a reduction smelting furnace for reduction smelting, the smelting temperature is controlled to be 800-1100°C and the smelting time is 30-180min, the lead-antimony alloy (capturing precious metals gold and silver) generated in the smelting process flows out through the metal liquid outlet, the produced slag is discharged through the slag outlet, and the generated flue gas is discharged into the atmosphere after waste heat recovery and flue gas treatment meet the standards.

[0028] Embodiment 1:

[0029] A method for recovering antimony, lead and precious metals by sulfidation reduction smelting of arsenic-removed lead anode mud, the specific steps are as follows:

[0030] Dearsenicized lead anode mud (lead content of 12.03wt.%, antimony content of 27.43wt.%, gold content of 0.707kg / t, silver content of 65.41kg / t), reducing agent coke (added amount of 15wt.%), sulfiding agent lead sulfide (added amount of 5wt.%) and slag-forming agent sodium carbonate (added amount of 20wt.%) are all ground to 80 mesh and evenly mixed, and then sent to a reduction smelting furnace for reduction smelting. The smelting temperature is controlled to be 1000℃ and the smelting time is 60min. The lead-antimony alloy generated in the smelting process flows out through the metal liquid outlet, the produced slag is discharged through the slag outlet, and the generated flue gas is discharged into the atmosphere after waste heat recovery and flue gas treatment meet the standards.

[0031] After the arsenic-removed lead anode mud was smelted by sulfide reduction, the antimony content in the slag was reduced to 1.43wt.%, the lead content was reduced to 0.14wt.%, and the content of precious metals gold and silver in the slag was reduced to 1.61g / t and 80.37g / t respectively. The process achieved efficient recovery of antimony, lead and precious metals gold and silver in the arsenic-removed lead anode mud.

[0032] Embodiment 2:

[0033] A method for recovering antimony, lead and precious metals by sulfidation reduction smelting of arsenic-removed lead anode mud, the specific steps are as follows:

[0034] The arsenic-free lead anode mud (lead content of 18.03wt.%, antimony content of 20.43wt.%, gold content of 0.407kg / t, silver content of 45.41kg / t), reducing agent coal powder (added amount of 10wt.%), sulfiding agent zinc sulfide (added amount of 3wt.%) and slag-forming agent sodium hydroxide (added amount of 15wt.%) are all ground to 100 mesh and evenly mixed, and then sent to a reduction smelting furnace for reduction smelting. The smelting temperature is controlled to 850°C and the smelting time is 180min. The lead-antimony alloy generated in the smelting process flows out through the metal liquid outlet, the produced slag is discharged through the slag outlet, and the generated flue gas is discharged into the atmosphere after waste heat recovery and flue gas treatment meet the standards.

[0035] After the arsenic-removed lead anode mud in the above process is smelted by sulfide reduction, it is detected and analyzed that the antimony content in the slag is reduced to 0.97wt.%, the lead content is reduced to 0.08wt.%, and the content of precious metals gold and silver in the slag is reduced to 1.82g / t and 100.37g / t respectively. The process realizes the efficient recovery of antimony, lead and precious metals gold and silver in the arsenic-removed lead anode mud.

[0036] Embodiment 3:

[0037] A method for recovering antimony, lead and precious metals by sulfidation reduction smelting of arsenic-removed lead anode mud, the specific steps are as follows:

[0038] The arsenic-free lead anode mud (lead content of 34.18wt.%, antimony content of 30.96wt.%, gold content of 0.587kg / t, silver content of 95.69kg / t), reducing agent blue carbon (added amount of 20wt.%), sulfiding agent arsenic sulfide (added amount of 15wt.%) and slag-forming agent sodium carbonate and sodium hydroxide mixture (sodium carbonate: sodium hydroxide mass ratio = 8:3, added amount of 30wt.%) are all ground to 200 mesh and evenly mixed, and then sent to a reduction smelting furnace for reduction smelting. The smelting temperature is controlled to 1100°C and the smelting time is controlled to 30min. The lead-antimony alloy generated in the smelting process flows out through the metal liquid outlet, the produced slag is discharged through the slag outlet, and the generated flue gas is discharged into the atmosphere after waste heat recovery and flue gas treatment meet the standards.

[0039] After the arsenic-removed lead anode mud in the above process is smelted by sulfide reduction, the antimony content in the slag is reduced to 2.97wt.%, the lead content is reduced to 0.48wt.%, and the content of precious metals gold and silver in the slag is reduced to 0.96g / t and 90.42g / t respectively. The process realizes the efficient recovery of antimony, lead and precious metals gold and silver in the arsenic-removed lead anode mud.

[0040] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for recovering antimony, lead and precious metals by sulfidation reduction smelting of arsenic-free lead anode mud, characterized in that: The method comprises the following steps: (1) Grinding the dearsenicized lead anode mud, reducing agent, sulfiding agent and slagging agent to a certain particle size and mixing them in a certain proportion; (2) The mixture is sent to a reduction smelting furnace for reduction smelting, and the smelting temperature and smelting time are controlled to generate a lead-antimony alloy and capture the precious metals; In step (1), the antimony content of the dearsenicized lead anode mud is 1-50 wt.%, the lead content is 1-50 wt.%, the gold content is 0.03-0.8 kg / t, and the silver content is 10-150 kg / t; In step (1), the reducing agent is at least one of coke, coal powder, natural gas or semi-coke; In step (1), the sulfiding agent is at least one of lead sulfide, zinc sulfide or arsenic sulfide.

2. The method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud according to claim 1, characterized in that: The amount of reducing agent added in step (1) is 1-25 wt.% of the dearsenicized lead anode mud.

3. The method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud according to claim 1, characterized in that: The amount of sulfiding agent added in step (1) is 1-15 wt.% of the dearsenicized lead anode mud.

4. The method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud according to claim 1, characterized in that: In step (1), the slagging agent is at least one of sodium carbonate and sodium hydroxide.

5. The method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud according to claim 1, characterized in that: The amount of slag-forming agent added in step (1) is 5-35 wt.% of the dearsenicized lead anode mud.

6. The method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud according to claim 1, characterized in that: In step (1), the grinding particle size of the dearsenicized lead anode mud, the reducing agent, the sulfiding agent and the slag-forming agent is 20-300 mesh.

7. The method for recovering antimony, lead and precious metals by sulfidation reduction smelting of dearsenicized lead anode mud according to claim 1, characterized in that: In step (2), the smelting temperature is 800-1100°C and the smelting time is 30-180 min.

Images