Process for extracting copper, lead and precious metals by vacuum distillation method

Abstract

The invention discloses a process for extracting copper, lead and precious metals by a vacuum distillation method. The process for extracting the copper, lead and precious metals by the vacuum distillation method comprises the following steps: step 1, preparing and pretreating raw materials; 2, plasma pretreatment; step 3, carrying out segmented heating and rotary distillation; step 4, multi-stage condensation; 5, online monitoring is carried out; according to the technology for extracting the copper-containing, lead-containing and precious metal through the vacuum distillation method, metal steam with different boiling points can be accurately separated at different temperature sections through a multi-stage condensation system, follow-up purification steps such as cross contamination, multi-stage condensation and electrolytic refining between the metals are avoided, the purity of the metals can be remarkably improved, and the purity of the copper-containing, lead-containing and precious metal is improved. The final product is ensured to meet the high-quality standard; the boiling point of metal in a vacuum environment is reduced, energy consumption required by heating is reduced, the rotary distiller is used, raw materials are continuously turned over in the heating process, uniform heating is guaranteed, the evaporation efficiency is improved, and residues are reduced.

Description

Technical Field

[0001] The invention relates to a process for extracting copper, lead and precious metals, in particular to a process for extracting copper, lead and precious metals by vacuum distillation, belonging to the technical field of extracting copper, lead and precious metals. Background Art

[0002] Vacuum distillation is a metallurgical technology that separates and purifies metals by heating the material under vacuum conditions so that different metals evaporate and condense in turn according to their respective evaporation temperatures. This method is particularly suitable for processing complex ores and secondary resources containing multiple metals. Compared with traditional pyrometallurgy and hydrometallurgy, vacuum distillation has significant advantages in many aspects.

[0003] Disadvantages of traditional pyrometallurgy and hydrometallurgy

[0004] Pyrometallurgy: high energy consumption. Pyrometallurgy usually requires extremely high temperatures to smelt metals, which leads to huge energy consumption, reduces energy utilization efficiency, and increases production costs; cross-contamination. During the high-temperature smelting process, cross-contamination is prone to occur between different metals, resulting in low purity of the final product. Multiple refining is required to achieve the required purity, further increasing time and cost; environmental pollution. Pyrometallurgy will produce a large amount of waste gas and waste slag. If not handled properly, it will cause serious pollution to the environment.

[0005] Hydrometallurgy: The use of chemical reagents. Hydrometallurgy requires the use of a large amount of chemical reagents, such as acids and alkalis, which not only increases costs, but also poses potential hazards to the environment and the health of operators. Complex process: The hydrometallurgical process is complex and requires multiple steps to achieve metal extraction and separation. The process is long and the operation is difficult. Low metal recovery rate: Due to the complexity of chemical reactions, the metal recovery rate of hydrometallurgy is relatively low, especially when dealing with multi-metal mixed ores, the separation effect is not ideal. Summary of the invention

[0006] The object of the present invention is to provide a process for extracting copper, lead and precious metals by vacuum distillation to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solution: a process for extracting copper, lead and precious metals by vacuum distillation, wherein the process steps for extracting copper, lead and precious metals by vacuum distillation are as follows:

[0008] Step 1: Raw material preparation and pretreatment: collect raw materials containing copper, lead and precious metals, crush and grind them to make the particle size uniform for subsequent processing;

[0009] Step 2: Plasma pretreatment, using plasma technology to heat and pretreat the raw materials, partially evaporate the metal components, and separate a portion of lead and copper in advance;

[0010] Step 3: Segmented heating and rotary distillation. The first stage is lead evaporation. The lead is evaporated and the rotary distiller is started. The evaporated lead gas enters the condenser, is cooled and collected. The second stage is copper evaporation. The copper is evaporated and the rotary distiller is continued to make the raw materials continue to be heated evenly and the copper evaporates more fully. The evaporated copper gas enters the condenser, is cooled and collected. The third stage is precious metal evaporation. According to the boiling point of the precious metal, the temperature is further raised to an appropriate temperature to evaporate the precious metal. The rotary distiller is continuously operated to ensure that the precious metal evaporates evenly. The evaporated precious metal gas enters the condenser, is cooled and collected.

[0011] Step 4: Multi-stage condensation: according to the different boiling points of the evaporated metals, different metals are condensed and collected at different temperature ranges to improve the collection efficiency and purity;

[0012] Step 5: Online monitoring: Install online monitoring equipment to monitor the temperature, pressure and gas composition in the distiller in real time to ensure accurate control of process parameters;

[0013] Step 6: Purification treatment: the extracted crude lead and crude copper are placed in the corresponding electrolyte solution for electrolytic purification to obtain refined products such as refined lead and refined copper.

[0014] As a preferred technical solution of the present invention, in the step 1, the raw materials containing copper, lead and precious metals are crushed into small pieces of 1-2 cm by using a jaw crusher, and then the crushed raw materials are crushed to less than 100 μm by using a ball mill, and then the raw materials are preliminarily sorted by gravity separation or magnetic separation to remove impurities.

[0015] As a preferred technical solution of the present invention, in the step 2, the plasma temperature is 800-1200° C., the processing time is 30 min-60 min, and the vacuum degree is 0.01-0.05 Torr.

[0016] As a preferred technical solution of the present invention, in the step three, the temperature is raised to the boiling point of lead 1700°C-1800°C, the rotation speed is 10-15RPM, and the evaporation time is 2-4 hours; the temperature is raised to the boiling point of copper 2500°C-2600°C, the rotation speed of the rotary distiller is 15-20RPM, and the evaporation time is 3-5 hours; in the third stage, the precious metal is evaporated at 2600-3000°C, the rotation speed is 20-30RPM, and the evaporation time is 4-6 hours.

[0017] As a preferred technical solution of the present invention, in step four, the first condensation stage lead: 300-400°C, the second condensation stage (copper): 1000-1200°C, the third condensation stage (precious metal): 1500-2000°C, and the cooling medium is one of high-temperature thermal conductive oil or liquid nitrogen.

[0018] As a preferred technical solution of the present invention, in step five, the online monitoring equipment installed includes temperature sensors, pressure sensor accuracy and body composition monitoring.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention is a process for extracting copper, lead and precious metals by vacuum distillation. Through a multi-stage condensation system, metal vapors with different boiling points can be accurately separated in different temperature ranges, avoiding cross contamination between metals. Subsequent purification steps such as multi-stage condensation and electrolytic refining can significantly improve the purity of the metal and ensure that the final product meets high quality standards. The boiling point of the metal is reduced in a vacuum environment, reducing the energy consumption required for heating. A rotary distiller is used to continuously turn the raw materials during the heating process to ensure uniform heating, improve evaporation efficiency and reduce residue. The temperature and cooling medium in the multi-stage condensation can be flexibly adjusted to meet the condensation requirements of different metals, thereby improving the adaptability and operational stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] The present invention provides a process for extracting copper, lead and precious metals by vacuum distillation. The process steps for extracting copper, lead and precious metals by vacuum distillation are as follows:

[0023] Step 1: Raw material preparation and pretreatment: collect raw materials containing copper, lead and precious metals, crush and grind them to make the particle size uniform for subsequent processing;

[0024] Step 2: Plasma pretreatment, using plasma technology to heat and pretreat the raw materials, partially evaporate the metal components, and separate a portion of lead and copper in advance;

[0025] Step 3: Segmented heating and rotary distillation. The first stage is lead evaporation. The lead is evaporated and the rotary distiller is started. The evaporated lead gas enters the condenser, is cooled and collected. The second stage is copper evaporation. The copper is evaporated and the rotary distiller is continued to make the raw materials continue to be heated evenly and the copper evaporates more fully. The evaporated copper gas enters the condenser, is cooled and collected. The third stage is precious metal evaporation. According to the boiling point of the precious metal, the temperature is further raised to an appropriate temperature to evaporate the precious metal. The rotary distiller is continuously operated to ensure that the precious metal evaporates evenly. The evaporated precious metal gas enters the condenser, is cooled and collected.

[0026] Step 4: Multi-stage condensation: according to the different boiling points of the evaporated metals, different metals are condensed and collected at different temperature ranges to improve the collection efficiency and purity;

[0027] Step 5: Online monitoring: Install online monitoring equipment to monitor the temperature, pressure and gas composition in the distiller in real time to ensure accurate control of process parameters;

[0028] Step 6: Purification treatment: the extracted crude lead and crude copper are placed in the corresponding electrolyte solution for electrolytic purification to obtain refined products such as refined lead and refined copper.

[0029] Among them, in the step 1, the raw materials containing copper, lead and precious metals are crushed into small pieces of 1-2 cm by using a jaw crusher, and then the crushed raw materials are crushed to less than 100 μm by using a ball mill, and then the raw materials are preliminarily sorted by gravity separation or magnetic separation to remove impurities.

[0030] Furthermore, in the step 2, the plasma temperature is 800-1200° C., the processing time is 30 min-60 min, and the vacuum degree is 0.01-0.05 Torr.

[0031] Furthermore, in the step three, the temperature is raised to the boiling point of lead 1700°C-1800°C, the rotation speed is 10-15RPM, and the evaporation time is 2-4 hours; the temperature is raised to the boiling point of copper 2500°C-2600°C, the rotation speed of the rotary distiller is 15-20RPM, and the evaporation time is 3-5 hours; in the third stage, the precious metal is evaporated at 2600-3000°C, the rotation speed is 20-30RPM, and the evaporation time is 4-6 hours.

[0032] Preferably, in step 4, the first condensation stage lead: 300-400°C, the second condensation stage (copper): 1000-1200°C, the third condensation stage (precious metal): 1500-2000°C, and the cooling medium is one of high-temperature thermal oil or liquid nitrogen.

[0033] Among them, in the step five, the online monitoring equipment installed includes temperature sensors, pressure sensor accuracy and body composition monitoring.

[0034] Embodiment 1:

[0035] Raw material preparation and pretreatment:

[0036] Raw materials: alloys containing lead, copper and precious metals;

[0037] Crushing: jaw crusher, particle size 1-2cm, ball mill (speed 400RPM, crushing time 3 hours, particle size <100μm);

[0038] Gravity separation: spiral chute, chute inclination 20 degrees, gravity separation time 1 hour;

[0039] Acid leaching treatment: 10% sulfuric acid solution, leaching temperature 70°C, leaching time 3 hours;

[0040] Washing and drying: Wash 3 times, drying temperature 110℃, drying time 2 hours.

[0041] 2. Vacuum distillation

[0042] Rotary distiller: rotation speed 100RPM, heating temperature 1100°C, vacuum degree 0.01Torr, distillation time 4 hours.

[0043] 3. Multi-stage condensation

[0044] Lead condensation: temperature 350℃, cooling medium is high temperature thermal oil;

[0045] Copper condensation: temperature 1100℃, cooling medium is high temperature thermal oil;

[0046] Precious metal condensation: temperature 1600℃, cooling medium is liquid nitrogen.

[0047] 4. Product Purification

[0048] Electrolytic refining: copper sulfate solution, electrolytic voltage 3V, electrolytic temperature 60℃, current density 150A / m 2 , electrolysis time 72 hours;

[0049] Condensation extraction of precious metals: 0.05M sodium cyanide solution (dissolution temperature 50°C, dissolution time 3 hours), precious metal precipitation is reduced by zinc powder, and the precipitation time is 2 hours.

[0050] Metal purity

[0051] Copper: 99.99%; Lead: 99.95%; Precious metal condensation: 99.99%.

[0052] Embodiment 2:

[0053] 1. Raw material preparation and pretreatment

[0054] - Raw materials: alloys containing lead, copper and precious metals;

[0055] - Crushing: jaw crusher (particle size 1-2 cm), ball mill (rotation speed 400 RPM, crushing time 3 hours, particle size <100 μm).

[0056] - Gravity separation: spiral chute (chute inclination 20 degrees, gravity separation time 1 hour).

[0057] 2. Melting and blowing

[0058] Smelting: Smelting at a high temperature of 1200℃, using coke as fuel;

[0059] Blowing: Use oxygen to blow to remove impurities.

[0060] 3. Refining

[0061] Lead refining: carried out at 1000°C, with the addition of an appropriate amount of reducing agent;

[0062] Copper refining: carried out at 1200°C, adding appropriate amount of oxidant;

[0063] Precious metal refining: Extraction by chemical precipitation during the smelting process.

[0064] 4. Product Purification

[0065] Electrolytic refining: copper sulfate solution, electrolytic voltage 3V, electrolytic temperature 60℃, current density 150A / m 2 , electrolysis time 72 hours;

[0066] Final metal purity: copper: 99.5%, lead: 99.0%; precious metals: 99.7%;

[0067] Embodiment three:

[0068] 1. Raw material preparation and pretreatment:

[0069] Raw materials: alloys containing lead, copper and precious metals;

[0070] Crushing: jaw crusher (particle size 1-2cm), ball mill (speed 400RPM, crushing time 3 hours, particle size <100μm);

[0071] Gravity separation: spiral chute (chute inclination 20 degrees, gravity separation time 1 hour);

[0072] 2. Acid leaching

[0073] Copper leaching: 10% sulfuric acid solution (leaching temperature 70°C, leaching time 3 hours);

[0074] Lead leaching: 5% nitric acid solution (leaching temperature 60°C, leaching time 2 hours);

[0075] Gold leaching: 0.05M sodium cyanide solution (dissolving temperature 50°C, dissolving time 3 hours).

[0076] 3. Metal precipitation

[0077] Copper precipitation: add an appropriate amount of reducing agent, such as iron powder, to reduce the precipitate;

[0078] Lead precipitation: by adding alkali precipitation method, adding NaOH precipitation;

[0079] Gold precipitation: The metal is precipitated by reduction with zinc powder.

[0080] 4. Product Purification

[0081] Electrolytic refining: copper sulfate solution, electrolytic voltage 3V, electrolytic temperature 60℃, current density 150A / m 2 , electrolysis time 72 hours;

[0082] Final metal purity: Copper: 99.7%; Lead: 99.2%; Gold: 99.5%.

[0083] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for extracting copper, lead and precious metals by vacuum distillation, characterized in that: The process steps of extracting copper, lead and precious metals by vacuum distillation are as follows: Step 1: Raw material preparation and pretreatment: collect raw materials containing copper, lead and precious metals, crush and grind them to make the particle size uniform for subsequent processing; Step 2: Plasma pretreatment, using plasma technology to heat and pretreat the raw materials, partially evaporate the metal components, and separate a portion of lead and copper in advance; Step 3: Segmented heating and rotary distillation. The first stage is lead evaporation. The lead is evaporated and the rotary distiller is started. The evaporated lead gas enters the condenser, is cooled and collected. The second stage is copper evaporation. The copper is evaporated and the rotary distiller is continued to make the raw materials continue to be heated evenly and the copper evaporates more fully. The evaporated copper gas enters the condenser, is cooled and collected. The third stage is precious metal evaporation. According to the boiling point of the precious metal, the temperature is further raised to an appropriate temperature to evaporate the precious metal. The rotary distiller is continuously operated to ensure that the precious metal evaporates evenly. The evaporated precious metal gas enters the condenser, is cooled and collected. Step 4: Multi-stage condensation: according to the different boiling points of the evaporated metals, different metals are condensed and collected at different temperature ranges to improve the collection efficiency and purity; Step 5: Online monitoring: Install online monitoring equipment to monitor the temperature, pressure and gas composition in the distiller in real time to ensure accurate control of process parameters; Step 6: Purification treatment: the extracted crude lead and crude copper are placed in the corresponding electrolyte solution for electrolytic purification to obtain refined products such as refined lead and refined copper.

2. The process for extracting copper, lead and precious metals by vacuum distillation according to claim 1, characterized in that: In the step 1, raw materials containing copper, lead and precious metals are crushed into small pieces of 1-2 cm by using a jaw crusher, and then the crushed raw materials are crushed to less than 100 μm by using a ball mill. Then, the raw materials are preliminarily sorted by gravity separation or magnetic separation to remove impurities.

3. The process for extracting copper, lead and precious metals by vacuum distillation according to claim 1, characterized in that: In the step 2, the plasma temperature is 800-1200° C., the processing time is 30 min-60 min, and the vacuum degree is 0.01-0.05 Torr.

4. The process for extracting copper, lead and precious metals by vacuum distillation according to claim 1, characterized in that: In the step three, the temperature is raised to the boiling point of lead 1700°C-1800°C, the rotation speed is 10-15RPM, and the evaporation time is 2-4 hours; the temperature is raised to the boiling point of copper 2500°C-2600°C, the rotation speed of the rotary distiller is 15-20RPM, and the evaporation time is 3-5 hours; in the third stage, the precious metal is evaporated at 2600-3000°C, the rotation speed is 20-30RPM, and the evaporation time is 4-6 hours.

5. The process for extracting copper, lead and precious metals by vacuum distillation according to claim 1, characterized in that: In step 4, the first condensation stage lead: 300-400°C, the second condensation stage (copper): 1000-1200°C, the third condensation stage (precious metal): 1500-2000°C, and the cooling medium is one of high-temperature thermal conductive oil or liquid nitrogen.

6. The process for extracting copper, lead and precious metals by vacuum distillation according to claim 1, characterized in that: In step five, online monitoring equipment including temperature sensors, pressure sensors, accuracy and body composition monitoring are installed.

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