WO2024124684A1 - Method for recovering lead, antimony and tin from complex lead-antimony hazardous waste material - Google Patents

Abstract

A method for recovering lead, antimony and tin from complex lead-antimony hazardous waste material, comprising the following steps: (1) side-blown reduction smelting: adding a certain amount of gangue and reducing coal into a complex lead-antimony-containing hazardous waste material, and placing the mixture into a side-blown reduction furnace for reduction smelting, to obtain an alloy; (2) tin separation: placing the alloy discharged by the side blowing reduction furnace in a stainless steel anode pot, heating and stirring to remove tin; (3) copper separation: further reducing the temperature of the alloy after stirring and tin removal, adding xylose, stirring and collecting slag, to obtain a lead-antimony alloy having a copper content of less than 0.2%, and casting the lead-antimony alloy into a lead-antimony alloy anode plate; (4) electrolytic refining: placing the lead-antimony anode plate into a lead electrolytic bath for electrolysis, and ingot casting to produce a refined lead ingot. The present method can produce qualified refined lead, the tin slag contains more than 30% tin, and the anode slurry contains more than 60% antimony. A single device can adapt to various different hazardous waste raw materials, the production cost is greatly reduced, and the production period is short.

Description

A method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials Technical Field

The invention relates to the technical field of pyrometallurgy, in particular to a method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials.

Background technique

In the traditional treatment of complex lead-antimony hazardous waste materials, according to the characteristics of the materials, the following methods are often used: 1. The lead-removing slag produced by antimony smelting and refining is first crushed, ball-milled, and alkaline-leached to obtain phosphorus-containing high-lead antimony oxide, and then the phosphorus-containing high-lead antimony oxide is put into a reverberatory furnace for reduction to obtain high-lead antimony. The high-lead antimony is continuously cycled through blowing-reduction-blowing-reduction to finally obtain antimony and lead, but the antimony-lead separation is not complete, the treatment process is long, time-consuming, the treatment cost is high, and there is no profit margin. 2. Small antimony smelters directly put lead-containing antimony slag into a blast furnace, add flux iron ore, flux sodium carbonate, coking coal, etc., and undergo high-temperature oxidation, reduction, oxidation and other processes to volatilize antimony and lead together to obtain high-lead antimony oxide, and then put it into a reverberatory furnace for reduction to obtain high-lead antimony, and then put the high-lead antimony into a blowing furnace, through blowing-reduction-blowing-reduction continuous cycle, finally obtain antimony oxide and lead, but the separation is also not complete, the treatment process is long, time-consuming, the treatment cost is high, and there is no profit margin.

Chinese patent CN201811348203 discloses a method for separating lead from antimony by fire method, which includes crushing the lead antimony slag, adding a reducing agent and mixing evenly, then placing it in a medium frequency induction furnace, heating and melting it, cooling it down for reaction, pouring out the antimony liquid, casting ingots, and obtaining antimony ingots. This method has the disadvantages of small processing capacity and high electricity cost.

Chinese patent CN105603197A discloses a reverberatory furnace treatment method for antimony slag or antimony smoke, which is similar to the treatment of antimony slag by adding flux iron ore, flux sodium carbonate, coking coal, etc. in a blast furnace. Although antimony is reduced, other impurity metals are also reduced at the same time, which has no effect on the separation of antimony and impurity metals; moreover, a large amount of iron ore and stone are added for slag making, which further causes the waste of iron ore and stone resources and increases the storage and reprocessing costs of waste slag.

Chinese patent CN101538658A discloses a new process for smelting antimony oxide slag, which is processed in a blast furnace for smelting lead-antimony alloy, and antimony oxide and the like are evaporated from the slag under high temperature and low pressure conditions. However, when the antimony oxide is evaporated, impurities such as lead oxide are also evaporated, and the effect of lead-antimony separation cannot be achieved. If lead-antimony separation is to be achieved, it is also necessary to use a continuous cycle of reduction-oxidation-reduction-oxidation to separate the lead and antimony, which not only takes a long time, but also consumes too much energy, and is not suitable for treating lead-antimony slag.

Chinese patent CN1908208A discloses a comprehensive process for recovering valuable metals from antimony oxychloride slag. Although it can separate antimony from slag well, it still has technical shortcomings such as long blowing time and high energy consumption. trap.

In summary, long-term research has been conducted on how to effectively and quickly treat complex lead-antimony hazardous waste materials, but no new technology has been found that can react quickly and effectively, efficiently separate antimony and lead, and adapt to a variety of different hazardous waste raw materials with a single device, and has low cost, profitability, short process, easy operation, and is new and environmentally friendly.

Summary of the invention

The purpose of the present invention is to solve the above technical problems and provide a method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials, which can produce tin products, copper products, lead products and antimony products respectively. A single device can be adapted to a variety of different hazardous waste raw materials, greatly reducing production costs and shortening the production cycle.

To achieve the above object, the technical solution of the present invention is as follows: Provide a method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials, comprising the following steps:

(1) Side-blowing reduction smelting: The complex lead-antimony hazardous waste is mixed with a certain amount of gangue and reducing coal, and then put into a side-blowing reduction furnace for reduction smelting. The reduction temperature is controlled at 1100°C-1300°C, and the reduction time is 60-90 minutes. The upper slag contains 2-4% of valuable metals, and the alloy and slag are discharged at different furnace ports respectively;

(2) Separation of tin: The alloy discharged from the side-blown reduction furnace is placed in a stainless steel anode pot, heated to 750-800°C, and placed in a stirrer to stir the metal for 1.5-2 hours. During this time, salt is added into the pot to form a film to prevent metal volatilization and loss. Finally, the tin slag is removed to obtain the alloy after stirring and tin removal;

(3) Separating copper: the alloy after stirring and removing tin is further cooled to 500-400°C, and xylose is added and stirred for 2-5 times to remove slag. The whole process takes 1.5-2 hours, during which salt is added into the pot to form a film to prevent metal volatilization and loss. Finally, the tin slag is removed to obtain a lead-antimony alloy with a copper content of less than 0.2% and cast into a lead-antimony alloy anode plate;

(4) Electrolytic refining: The lead-antimony anode plates are placed in lead electrolytic cells for electrolysis, and the electrolytic current density is controlled to be no more than 150A/m2. The precipitated cathode lead ingots are then cast into refined lead ingots, and the anode mud containing 60% antimony is produced for recovery of antimony products.

The total grade of valuable nonferrous metals in the raw materials is greater than 10%, and the sulfur content in the raw materials is not more than 5%.

Unless otherwise specified, the percentages described in the present invention are all mass percentages, and the sum of the percentages of each component is 100%.

The outstanding advantages of the present invention are:

The present invention can produce qualified refined lead, tin slag containing more than 30% tin, and anode mud containing more than 60% antimony. A single device can be used for a variety of hazardous waste materials, greatly reducing production costs and shortening production cycles.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a process flow chart of the method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to the present invention.

Detailed ways

The technical solution of the present invention is further described in detail below in conjunction with embodiments, but the implementation mode of the present invention is not limited to the scope represented by the embodiments.

Example 1

This embodiment is an example of the method for recovering lead, antimony and tin from complex lead, antimony and hazardous waste materials according to the present invention, comprising the following steps:

Step 1: Add 40% lead, 10% antimony and 2% tin hazardous waste materials into 10% reducing coal, and evenly feed them into an 8.4 square meter side-blown reduction furnace through a feeding belt. Feed 30 tons of materials within 20 minutes, and then carry out reduction smelting at a temperature of 1200°C for 70 minutes. After the reduction, the alloy and slag are discharged from different furnace ports respectively, and the furnace is placed for 25 minutes. 12 tons of lead-antimony crude alloy containing 83% lead, 14% antimony and 2% tin are produced, and 15 tons of slag containing 1.8% lead, 1.4% antimony and 0.3% tin are produced. Repeat this step 5 times until 50 tons of lead-antimony crude alloy are produced.

Step 2: Put 50 tons of lead-antimony crude alloy discharged from the side-blown reduction furnace into a stainless steel anode pot with a capacity of 1 cubic meter, heat it to 800°C with natural gas, put it into a mixer and stir it for 1.5 hours, add 30 kg of salt into the pot, and then remove 3 tons of tin slag, which contains 32% Sn, 8% Pb, and 2% antimony. Obtain the lead-antimony crude alloy liquid after removing the tin slag;

Step 3: Use a lead pump to extract the lead-antimony crude alloy liquid after removing the tin slag and inject it into another cast steel anode pot, and slowly cool it down to 450°C under stirring. Remove the scum when it appears on the surface. The whole stirring time is 90 minutes, and 1 ton of copper slag (containing Cu15%, Pb55%, Sb15%) is removed. The lead-antimony crude alloy liquid after removing the copper slag is obtained;

Step 4: Casting lead-antimony alloy anode plates with the lead-antimony crude alloy liquid after scooping out the copper slag. The lead-antimony alloy anode plates contain 82% Pb, 16% Sb and 0.2% Cu. The lead-antimony alloy anode plates are placed in a lead electrolysis cell for electrolysis. Each lead-antimony alloy anode plate weighs 90 kg, and each cell is loaded with 35 _plates . The current density is 150 A/m2. The electrolyte composition is: _H2SiF6 (total) _115.08 g/L, Pb2 ⁺ 42.77 g/L, _H2SiF6 (free) 85.33 g/L. The power-on time is 70 hours. The precipitated lead meets the national standard of 0# refined lead. The anode mud contains Pb15%, Sb62% and Cu1.5%.

Example 2

This embodiment is another example of the method for recovering lead, antimony and tin from complex lead, antimony and hazardous waste materials of the present invention, comprising the following steps:

Step 1: Add 25% lead, 8% antimony and 1% tin hazardous waste into 10% reducing coal, and evenly feed it into a 8.4 square meter side-blown reduction furnace through a feeding belt. Feed 30 tons of materials within 20 minutes, and then carry out reduction smelting at a temperature of 1180°C for 60 minutes. After the reduction, the alloy and slag are discharged from different furnace ports respectively, and the furnace is placed for 25 minutes. 9 tons of lead-antimony crude alloy containing 81% lead, 16% antimony and 1.5% tin are produced, and 18 tons of slag containing 1.8% lead, 1.4% antimony and 0.3% tin are produced. Repeat this step 6 times until 50 tons of lead-antimony crude alloy are produced.

Step 2: 50 tons of lead-antimony crude alloy discharged from the side-blown reduction furnace are placed in a stainless steel anode pot with a capacity of 1 cubic meter, heated to 800° C. with natural gas, and placed in a stirrer for 1.5 hours, during which 30 kg of salt is added into the pot, and then 2 tons of tin slag containing 36% Sn, 5% Pb, and 2% antimony are removed to obtain a lead-antimony crude alloy liquid after the tin slag is removed;

Step 3, the lead-antimony crude alloy liquid after the tin slag is removed is pumped out with a lead pump and injected into another cast steel anode pot, and the temperature is slowly lowered to 450° C. under stirring. During this period, scum is removed when there is scum on the surface. The whole stirring time is 100 minutes, and 1 ton of copper slag containing Cu12%, Pb60%, and Sb17% is removed to obtain the lead-antimony crude alloy liquid after the copper slag is removed;

Step 4, casting lead-antimony alloy anode plates with the lead-antimony crude alloy liquid after the copper slag is removed, the lead-antimony alloy anode plates contain Pb82%, Sb16%, and Cu0.2%, and the lead-antimony alloy anode plates are placed in a lead electrolysis cell for electrolysis, each lead-antimony alloy anode plate weighs 90Kg, 35 plates are placed in each cell, the current density is 150A/m2, the electrolyte composition is: _H2SiF6 (total) _112.08g /L, Pb2 ⁺ 45.71g/L, _H2SiF6 (free) _88.23g /L, the power-on time is 70 hours, the precipitated lead meets the national standard 0# refined lead, and the anode mud contains Pb12%, Sb65%, and Cu1.8%.

Example 3

This embodiment is another example of the method for recovering lead, antimony and tin from complex lead, antimony and hazardous waste materials of the present invention, comprising the following steps:

Step 1: Add 20% lead, 5% antimony and 1% tin hazardous waste into 10% reducing coal, and evenly feed it into an 8.4 square meter side-blown reduction furnace through a feeding belt. Feed 30 tons of materials within 20 minutes, and then carry out reduction smelting at a temperature of 1150°C for 65 minutes. After the reduction, the alloy and slag are discharged from different furnace ports respectively, and the furnace is placed for 25 minutes. 6.7 tons of lead-antimony crude alloy containing 82.5% lead, 15.6% antimony and 2.1% tin are produced, and 20.5 tons of slag containing 1.8% lead, 1.4% antimony and 0.3% tin are produced. Repeat this step 8 times until 50 tons of lead-antimony crude alloy are produced.

Step 2: 50 tons of lead-antimony crude alloy discharged from the side-blown reduction furnace are placed in a stainless steel anode pot with a capacity of 1 cubic meter, heated to 800° C. with natural gas, and placed in a mixer for stirring for 100 minutes, during which 30 kg of salt is added into the pot, and then 2.7 tons of tin slag containing 36.5% Sn, 5.5% Pb, and 2.1% antimony are removed to obtain a lead-antimony crude alloy liquid after the tin slag is removed;

Step 3, the lead-antimony crude alloy liquid after the tin slag is removed is pumped out with a lead pump and injected into another cast steel anode pot, and the temperature is slowly lowered to 450° C. under stirring. During this period, scum is removed when there is scum on the surface. The whole stirring time is 100 minutes, and 1 ton of copper slag containing Cu16.5%, Pb66.1%, and Sb16.7% is removed to obtain the lead-antimony crude alloy liquid after the copper slag is removed;

Step 4, the lead-antimony alloy crude liquid after the copper slag is scooped out is used to cast lead-antimony alloy anode plates, the lead-antimony alloy anode plates contain Pb82%, Sb16%, and Cu0.2%, and the lead-antimony alloy anode plates are placed in a lead electrolysis cell for electrolysis, each lead-antimony alloy anode plate weighs 90Kg, and each cell is loaded with 35 plates. The current density is _145A /m2, and the electrolyte composition is: _H2SiF6 (total) 118.18g/L, Pb2 ⁺ 46.87g/L, _H2SiF6 (free) _88.37g /L, and the power-on time is 65 hours. The precipitated lead meets the national standard 0# refined lead standard, and the anode mud contains Pb12.1%, Sb66.4%, and Cu1.7%.

The above embodiments are only specific examples for further describing the purpose, technical solutions and beneficial effects of the present invention, and the present invention is not limited thereto. Any modification, equivalent replacement, improvement, etc. made within the scope disclosed by the present invention are included in the protection scope of the present invention.

Claims (10)

A method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials, characterized in that it comprises the following steps: (1) Side-blowing reduction smelting: The complex lead-antimony hazardous waste is mixed with a certain amount of gangue and reducing coal, and then put into a side-blowing reduction furnace for reduction smelting. The reduction temperature is controlled at 1100°C-1300°C, and the reduction time is 60-90 minutes. The upper slag contains 2-4% of valuable metals, and the alloy and slag are discharged at different furnace ports respectively; (2) Separation of tin: The alloy discharged from the side-blown reduction furnace is placed in a stainless steel anode pot, heated to 750-800°C, and placed in a stirrer to stir the metal for 1.5-2 hours. During this time, salt is added to the pot to form a film to prevent metal volatilization and loss. Finally, the tin slag is removed to obtain the alloy after stirring and tin removal; (3) Separating copper: the alloy after stirring and removing tin is further cooled to 500-400°C, and xylose is added and stirred for 2-5 times to remove slag. The whole process takes 1.5-2 hours to obtain a lead-antimony alloy with a copper content of less than 0.2% and cast into a lead-antimony alloy anode plate; (4) Electrolytic refining: The lead-antimony anode plates are placed in lead electrolytic cells for electrolysis, and the electrolytic current density is controlled to be no more than 150A/m2. The precipitated cathode lead ingots are then cast into refined lead ingots, and the anode mud containing 60% antimony is produced for recovery of antimony products. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the total grade of valuable non-ferrous metals in the raw materials is greater than 10%, and the sulfur content in the raw materials is not more than 5%. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the complex lead-antimony hazardous waste materials are lead-antimony hazardous waste materials containing 40% lead, 10% antimony and 2% tin. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the complex lead-antimony hazardous waste materials are lead-antimony hazardous waste materials containing 25% lead, 8% antimony and 1% tin. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the complex lead-antimony hazardous waste materials are lead-antimony hazardous waste materials containing 20% lead, 5% antimony and 1% tin. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the side-blowing reduction furnace is an 8.4 square meter side-blowing reduction furnace. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the capacity of the stainless steel anode pot is a stainless steel anode pot of 1 cubic meter. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the lead-antimony alloy anode plate in step (4) contains Pb82%, Sb16%, and Cu0.2%, and the lead-antimony alloy anode plate is loaded into a lead electrolysis cell for electrolysis, each lead-antimony alloy anode plate weighs 90 kg, and each cell is loaded with 35 plates. Current density: 150A/m2, electrolyte composition: _H2SiF6 (total) _115.08g /L, Pb2 ⁺ 42.77g/L, _H2SiF6 (free) 85.33g/L, power-on time: 70 hours, the precipitated lead meets the national standard of 0# refined lead, _and the anode mud contains Pb15%, Sb62%, and Cu1.5%. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the lead-antimony alloy anode plate in step (4) contains Pb82%, Sb16%, and Cu0.2%, and the lead-antimony alloy anode plate is placed in a lead electrolysis cell for electrolysis, each lead-antimony alloy anode plate weighs 90 kg, 35 plates are placed in each cell, the current density is 150 A/m2, the electrolyte composition is: _H2SiF6 (total) _112.08 g/L, Pb2 ⁺ 45.71 g/L, _H2SiF6 (free) 88.23 g/L, the power-on time is 70 hours, the precipitated lead meets the national standard 0# refined lead standard, _and the anode mud contains Pb12%, Sb65%, and Cu1.8%. The method for recovering lead, antimony and tin from complex lead-antimony hazardous waste materials according to claim 1 is characterized in that the lead-antimony alloy anode plate in step (4) contains Pb82%, Sb16%, and Cu0.2%, and the lead-antimony alloy anode plate is placed in a lead electrolysis cell for electrolysis, each lead-antimony alloy anode plate weighs 90 kg, 35 plates are placed in each cell, the current density is 145 A/m2, the electrolyte composition is: _H2SiF6 (total) 118.18 _g /L, Pb2 ⁺ 46.87 g/L, _H2SiF6 (free) 88.37 g/L, the power-on time is 65 hours, the precipitated lead meets the national standard 0# refined lead standard, _and the anode mud contains Pb12.1%, Sb66.4%, and Cu1.7%.