Method for treating copper cobalt oxide ore

Abstract

The invention discloses a method for treating copper cobalt oxide ore, and belongs to the technical field of non-ferrous metal hydrometallurgy. The method comprises the following steps: carrying out critical leaching on the copper-cobalt oxide ore to obtain a leaching solution and leaching residues, returning the leaching residues to a wastewater and waste residue neutralization process, carrying out a sulfuration sectional copper-cobalt deposition process on the leaching solution to obtain two products of copper sulfide and cobalt sulfide, carrying out targeted adsorption cobalt recovery on the produced sulfurized solution, returning the desorbed solution to a critical leaching process, and carrying out secondary leaching on the desorbed solution. After adsorption, liquid enters a waste water and waste residue neutralization process, produced neutralization residues are piled up, and produced neutralization water is returned to a critical leaching process. The method sequentially comprises the key procedures of critical leaching, vulcanization segmented copper and cobalt deposition, targeted adsorption and waste water and waste residue neutralization. The process adopted by the invention has the advantages of short process flow, high recovery rate, zero discharge of wastewater and the like. Compared with a traditional process, the copper and cobalt leaching rates can reach 90% or above, and the cobalt recovery rate can be increased by 10% or above.

Description

Technical Field

[0001] The invention belongs to the technical field of nonferrous metal hydrometallurgy, and in particular relates to a method for treating copper-cobalt oxide ore. Background Art

[0002] At present, the main production area of ​​copper-cobalt oxide ores in the world is in the Democratic Republic of the Congo in Africa. The typical process flow of copper-cobalt oxide ores is: leaching - extraction - iron and manganese removal - copper and aluminum removal - cobalt precipitation - magnesium precipitation - tailings. The process of removing iron and manganese and copper and aluminum produces a large amount of iron-manganese slag and copper-aluminum slag. The two slags are rich in valuable metals such as copper and cobalt, with a large loss rate of copper and cobalt and a low recovery rate of cobalt. In a hydrometallurgical project of copper-cobalt oxide with an annual production capacity of 5,000 tons of cobalt, the annual loss of copper and cobalt is about 500 tons and 1,000 tons. Summary of the invention

[0003] Aiming at the problem of low cobalt recovery rate in the wet refining process of copper-cobalt oxide ore, the present invention provides a method for treating copper-cobalt oxide ore. The main process flow of the method is: critical leaching - sulfidation segmented copper and cobalt precipitation - targeted adsorption - wastewater and waste residue neutralization. The process is adopted to realize the recovery of copper and cobalt in the copper-cobalt oxide ore and greatly improve the recovery rate of cobalt.

[0004] Under the condition of reasonable control of critical leaching technical conditions, this method can open the lattice of copper-cobalt oxide ore, change the existence form of copper and cobalt, and convert trivalent cobalt in copper-cobalt oxide ore into divalent cobalt, so that copper and cobalt enter the solution. Compared with the traditional process, the copper-cobalt leaching rate can be greatly improved, and the copper-cobalt leaching rate can reach more than 90%; the copper and cobalt can be effectively separated by sulfidation segmented precipitation of copper and cobalt; the remaining cobalt ions can be adsorbed in the cobalt precipitation solution by targeted adsorption. The present invention adopts a new wet refining process, which realizes zero wastewater discharge through critical leaching, sulfidation segmented precipitation of copper and cobalt, targeted adsorption and wastewater and waste residue neutralization technology, and can increase the cobalt recovery rate by more than 10%. The process is simple and easy, the cobalt recovery rate is high, and the economic benefits are significant.

[0005] The objective of the present invention is achieved through the following technical solutions: 1) Critical leaching: The critical leaching technology is used for the oxidized copper-cobalt ore. Under the condition of reasonable control of the leaching technical conditions, the lattice of the oxidized copper-cobalt ore can be opened, the existence form of copper and cobalt can be changed, and copper and cobalt can enter the solution, which can greatly improve the copper-cobalt leaching rate. At the same time, the trivalent cobalt in the oxidized copper-cobalt ore is converted into divalent cobalt, increasing the leaching rate of cobalt. The copper-cobalt leaching rate can reach 90%. After the oxidized copper-cobalt ore is ground, it is mixed according to the liquid-solid ratio, and the pH is adjusted with sulfuric acid. The prepared slurry is pumped into the reactor, and SO2 gas is introduced into the reactor to maintain a certain temperature and pressure so that the reactor reaches the critical leaching requirements and starts the reaction. Critical leaching conditions: temperature 95-105℃, pressure 0.05-0.1MPa, pH1.0~2.0, liquid-solid ratio 3-5:1, SO2 dosage 24~40Nm 3 / ton of ore, reaction time 2-4h.

[0006] 2) Sulfidation and segmented precipitation of copper and cobalt: Through step 1), copper, cobalt, iron, manganese, aluminum and other impurities in the oxidized copper-cobalt ore enter the leaching solution. Add sulfidizing agent to the leaching solution, the amount of copper ions and sulfidizing agent added is 0.9~1.2 times the theoretical amount, control the redox potential to 200-300mv, the copper precipitation rate is greater than 95-99%, and the output copper sulfide slag contains 40-55% copper, which is sold as copper concentrate. The copper content of the solution after copper precipitation is 0.002-0.005g / L. The copper-precipitated liquid is then used for cobalt precipitation. A sulfiding agent is added to the leaching solution. The amount of cobalt ions and sulfiding agent added is 0.9-1.2 times the theoretical amount. The redox potential is controlled at -100-100mv. The cobalt precipitation rate is greater than 95-99%. The produced cobalt sulfide liquid contains 0.1-0.2g / L of cobalt and 2-4g / L of iron. The cobalt sulfide slag contains 50-60% cobalt and is sold as cobalt concentrate.

[0007] 3) Targeted adsorption to recover cobalt: The sulfided liquid produced in step 2) uses a special targeted resin to efficiently recover cobalt and achieve cobalt-iron separation. The adsorbed liquid contains 0.001-0.005 g / L cobalt and 2-4 g / L iron. The adsorption process conditions are: pH 0.5, solution flow rate 10 BV / h, after the resin is saturated with adsorption, it needs to be analyzed, and the analyzed resin is recycled. The analytical process conditions are: analytical liquid flow rate 1-4 BV / h, analytical acid 20-40% sulfuric acid, analytical liquid contains 25-50 g / L cobalt, and 0.1-0.5 g / L iron.

[0008] 4) Neutralization of wastewater and waste residue: The leached residue produced in step 1 and the adsorbed liquid produced in step (3) are slurried, and magnesium oxide is added for neutralization and precipitation. The pH is adjusted to 9.0-10.0, and the generated neutralized water enters the critical leaching process in step 1). The generated neutralized residue is stored.

[0009] The beneficial effects of the present invention are: 1. The present invention proposes a method for treating oxidized copper-cobalt ore in the Democratic Republic of the Congo, Africa, and adopts critical leaching, sulfidation segmented copper-cobalt precipitation, targeted adsorption, and wastewater and waste residue neutralization new technologies to treat oxidized copper-cobalt ore. It can achieve efficient recycling of copper and cobalt, shorten the process flow, and significantly reduce investment and cost.

[0010] 2. The present invention adopts critical leaching, which greatly improves the copper-cobalt leaching rate. The critical leaching process can open the lattice of the copper-cobalt oxide ore, and at the same time convert the trivalent cobalt in the copper-cobalt oxide ore into divalent cobalt, change the existence form of copper and cobalt, and allow copper and cobalt to enter the solution, which can greatly improve the copper-cobalt leaching rate and reduce the copper and cobalt taken out of the leaching residue, thereby greatly improving the recovery rate of copper and cobalt.

[0011] 3. The critical leaching adopted in the present invention has the advantage of high recovery rate of pressurized leaching, and avoids the defects of high temperature, high pressure, expensive pressure vessel, long processing cycle of special equipment, and great difficulty in production and operation. The "critical leaching" process is just right for the leaching of copper and cobalt in the copper-cobalt oxide ore.

[0012] 4. The present invention omits the traditional iron removal process and directly recovers copper and cobalt from the solution containing iron and other impurities through the sulfidation process. The obtained copper sulfide and cobalt sulfide slag can be directly sold as products, avoiding the traditional process of iron removal and other processes taking away valuable metals, and effectively improving the cobalt recovery rate again.

[0013] 5. The liquid after sulfide precipitation in the present invention is directly connected to the targeted resin adsorption, and the trace residual cobalt in the solution is directly adsorbed and recovered from the liquid after precipitation, thereby further improving the recovery rate of cobalt in the whole process.

[0014] 6. In the present invention, the liquid after sulfide precipitation and the leaching residue are mixed and neutralized, and the neutralization pH is controlled to meet the requirements of the external payment of the leaching residue. At the same time, the neutralized liquid is returned to the critical leaching process to realize the recycling of water resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0016] A method for treating copper-cobalt oxide ore, the process flow is shown in Figure 1 The specific process flow is briefly described as follows: the copper-cobalt oxide ore is first subjected to critical leaching to obtain leaching solution and leaching residue, the leaching residue is returned to the wastewater and waste residue neutralization process, the leaching solution enters the sulfidation segmented copper-cobalt precipitation process, and copper sulfide and cobalt sulfide are obtained respectively; the output sulfided liquid enters the targeted adsorption to recover cobalt, the analysis liquid of the targeted adsorption is returned to the critical leaching process for recycling, the adsorbed liquid of the targeted adsorption enters the wastewater and waste residue neutralization process, the output neutralized slag is stored, and the output neutralized water is returned to the critical leaching process for recycling.

[0017] Example 1 A method for treating copper-cobalt oxide ore, wherein the key steps of the treatment process include: 1) Critical leaching: After the copper-cobalt oxide ore is ground to -200 mesh ≥80%, sulfuric acid and copper sulfate are added at the same time, and the ingredients are prepared according to a liquid-solid ratio of 3:1. The prepared slurry is pumped into the reactor and SO2 gas is introduced into the reactor. Critical leaching conditions: temperature 105℃, pressure 0.05MPa, pH 1.5, SO2 dosage 24Nm 3 / ton of ore, reaction time 2h. The copper leaching rate reaches 92%, and the cobalt leaching rate reaches 91%.

[0018] 2) Sulfidation staged copper and cobalt precipitation: through step 1), add sulfiding agent to the leaching solution, the amount of copper ions and sulfiding agent added is 1.0 times the theoretical amount, control the redox potential to 300mv, the copper precipitation rate is 98%, and the output copper sulfide slag contains 45% copper. The copper content of the copper precipitation liquid is 0.002g / L. The copper precipitation liquid is then cobalt-precipitated, and the sulfiding agent is added to the leaching solution. The amount of cobalt ions and sulfiding agent added is 0.9 times the theoretical amount, control the redox potential to 10mv, the cobalt precipitation rate is greater than 95%, and the output cobalt sulfide liquid contains 0.2g / L cobalt, 3g / L iron, and the cobalt sulfide slag contains 50% cobalt.

[0019] 3) Targeted adsorption to recover cobalt: The sulfided liquid produced in step 2) is separated from cobalt and iron using targeted resin. The adsorbed liquid contains 0.005 g / L cobalt and 3 g / L iron. The adsorption process conditions are: solution flow rate 10 BV / h, analytical liquid flow rate 4 BV / h, analytical acid is 25% sulfuric acid, analytical liquid contains 30 g / L cobalt and 0.2 g / L iron.

[0020] 4) Neutralization of wastewater and waste residue: The leaching residue produced in step 1 and the adsorption liquid produced in step 3) are neutralized and precipitated with magnesium oxide, and the pH is adjusted to 10. The neutralized water produced enters the critical leaching process in step 1). The neutralized residue produced is stored.

[0021] Example 2 A method for treating copper-cobalt oxide ore, wherein the key steps of the treatment process include: 1) Critical leaching: After the copper-cobalt oxide ore is ground to -200 mesh ≥80%, sulfuric acid and copper sulfate are added at the same time, and the ingredients are prepared according to a liquid-solid ratio of 4:1. The prepared slurry is pumped into the reactor, and SO2 gas is introduced into the reactor. The critical leaching conditions are: temperature 100℃, pressure 0.1MPa, pH 1.0, liquid-solid ratio 4:1, and SO2 dosage is 30Nm 3 / ton of ore, reaction time 3h. The copper leaching rate reached 91%, and the cobalt leaching rate reached 90.5%.

[0022] 2) Sulfidation staged copper and cobalt precipitation: through step 1), add sulfiding agent to the leaching solution, the amount of copper ions and sulfiding agent added is 0.9 times the theoretical amount, control the redox potential to 260mv, the copper precipitation rate is 95%, and the output copper sulfide slag contains 40% copper. The copper precipitation liquid contains 0.005g / L of copper. The copper precipitation liquid is then cobalt-precipitated, and sulfiding agent is added to the leaching solution, the amount of cobalt ions and sulfiding agent added is 1.2 times the theoretical amount, control the redox potential to 100mv, the cobalt precipitation rate is greater than 99%, and the output cobalt sulfide liquid contains 0.1g / L of cobalt, 2g / L of iron, and the cobalt sulfide slag contains 60% cobalt.

[0023] 3) Targeted adsorption to recover cobalt: The sulfided liquid produced in step 2) is separated from cobalt and iron using targeted resin. The adsorbed liquid contains 0.001 g / L cobalt and 2 g / L iron. The adsorption process conditions are: solution flow rate 10 BV / h, analytical liquid flow rate 1 BV / h, analytical acid is 40% sulfuric acid, analytical liquid contains 50 g / L cobalt and 0.5 g / L iron.

[0024] 4) Neutralization of wastewater and waste residue: The leached residue produced in step 1 and the adsorption liquid produced in step 3) are slurried, and magnesium oxide is added for neutralization and precipitation. The pH is adjusted to 9.5, and the generated neutralized water enters the critical leaching process in step 1). The generated neutralized residue is stored.

[0025] Example 3 A method for treating copper-cobalt oxide ore, wherein the key steps of the treatment process include: 1) Critical leaching: After the copper-cobalt oxide ore is ground to -200 mesh ≥80%, sulfuric acid and copper sulfate are added at the same time, and the ingredients are prepared according to a liquid-solid ratio of 5:1. The prepared slurry is pumped into the reactor, and SO2 gas is introduced into the reactor. The critical leaching conditions are: temperature 105℃, pressure 0.08MPa, pH 1.5, SO2 dosage 35Nm 3 / ton of ore, reaction time 4h. The copper leaching rate reaches 93%, and the cobalt leaching rate reaches 92%.

[0026] 2) Sulfidation staged copper and cobalt precipitation: through step 1), add sulfiding agent to the leaching solution, the amount of copper ions and sulfiding agent added is 1.1 times the theoretical amount, control the redox potential to 300mv, the copper precipitation rate is 99%, and the output copper sulfide slag contains 55% copper. The copper content of the copper precipitation liquid is 0.003g / L. The copper precipitation liquid is then cobalt-precipitated, and a sulfiding agent is added to the leaching solution. The amount of cobalt ions and sulfiding agent added is 1.1 times the theoretical amount, control the redox potential to -50mv, the cobalt precipitation rate is greater than 98%, and the output cobalt sulfide liquid contains 0.1g / L cobalt, 4g / L iron, and the cobalt sulfide slag contains 54% cobalt.

[0027] 3) Targeted adsorption to recover cobalt: The sulfided liquid produced in step 2) is separated from cobalt and iron using targeted resin. The adsorbed liquid contains 0.005 g / L cobalt and 4 g / L iron. The adsorption process conditions are: solution flow rate 10 BV / h, analytical liquid flow rate 3 BV / h, analytical acid is 35% sulfuric acid, analytical liquid contains 45 g / L cobalt and 0.2 g / L iron.

[0028] 4) Neutralization of wastewater and waste residue: The leached residue produced in step 1 and the post-adsorption liquid produced in step 3) are slurried, and magnesium oxide is added for neutralization and precipitation. The pH is adjusted to 9.0, and the generated neutralized water enters the critical leaching process in step 1). The generated neutralized residue is stored.

[0029] Example 4 A method for treating copper-cobalt oxide ore, wherein the key steps of the treatment process include: 1) Critical leaching: After the copper-cobalt oxide ore is ground to -200 mesh ≥80%, sulfuric acid and copper sulfate are added at the same time, and the ingredients are prepared according to a liquid-solid ratio of 3:1. The prepared slurry is pumped into the reactor, and SO2 gas is introduced into the reactor. The critical leaching conditions are: temperature 95°C, pressure 0.1MPa, pH 1.0, and SO2 dosage 40Nm 3 / ton of ore, reaction time 2h. The copper leaching rate reaches 92%, and the cobalt leaching rate reaches 91%.

[0030] 2) Sulfidation staged copper and cobalt precipitation: through step 1), add sulfiding agent to the leaching solution, the amount of copper ions and sulfiding agent added is 1.2 times the theoretical amount, control the redox potential to 200mv, the copper precipitation rate is 96%, and the output copper sulfide slag contains 50% copper. The copper content of the copper precipitation liquid is 0.004g / L. The copper precipitation liquid is then cobalt-precipitated, and the sulfiding agent is added to the leaching solution. The amount of cobalt ions and sulfiding agent added is 1.0 times the theoretical amount, control the redox potential to -100mv, the cobalt precipitation rate is greater than 96%, and the output cobalt sulfide liquid contains 0.2g / L cobalt, 3g / L iron, and the cobalt sulfide slag contains 52% cobalt.

[0031] 3) Targeted adsorption to recover cobalt: The sulfided liquid produced in step 2) is separated from cobalt and iron using targeted resin. The adsorbed liquid contains 0.004 g / L cobalt and 3 g / L iron. The adsorption process conditions are: solution flow rate 10 BV / h, analytical liquid flow rate 1 BV / h, analytical acid is 20% sulfuric acid, analytical liquid contains 25 g / L cobalt and 0.1 g / L iron.

[0032] 4) Neutralization of wastewater and waste residue: The leaching residue produced in step 1 and the adsorption liquid produced in step 3) are neutralized and precipitated with magnesium oxide, and the pH is adjusted to 10.0. The generated neutralized water enters the critical leaching process in step 1). The generated neutralized residue is stored.

Claims

1. A method for treating copper-cobalt oxide ore, characterized in that: The following steps are involved: 1) Critical leaching: After the copper-cobalt oxide ore is ground to -200 mesh ≥80%, 98% concentrated sulfuric acid and copper sulfate solid ingredients are added in proportion, the prepared slurry is pumped into the reactor, SO2 gas is introduced into the reactor, the temperature and pressure required for the reaction are maintained, the reactor reaches the critical leaching requirements, and the reaction begins; the leaching residue and leaching liquid are obtained; 2) Sulfidation and segmented copper precipitation: adding a sulfiding agent to the copper-cobalt oxide ore leachate obtained in step 1), controlling the precipitation conditions so that the sulfiding agent first reacts with the copper ions in the leachate to obtain copper sulfide slag, filtering the copper sulfide slag to obtain copper sulfide slag and a copper precipitation liquid; continuing to add the sulfiding agent to the copper precipitation liquid to allow the cobalt ions to react with the sulfiding agent to obtain cobalt sulfide slag, and filtering and separating after the cobalt precipitation reaction to obtain cobalt sulfide slag and a cobalt precipitation liquid; 3) Targeted adsorption of cobalt: The cobalt-precipitated solution produced in step 2) is used to recover the cobalt in the solution using targeted resin, and iron and other impurities are suppressed in the solution; 4) Neutralization of wastewater and waste residue: The leaching residue produced in step 1) and the adsorption liquid produced in step 3) are slurried, magnesium oxide is added for neutralization and precipitation, the pH is adjusted to 9.0-10.0, and neutralized liquid and neutralized residue are produced; the neutralized liquid is returned to the critical leaching process in step 1) to realize water recycling, and the leaching residue is neutralized and stored.

2. The method for treating copper-cobalt oxide ore according to claim 1, characterized in that: The chemical composition of the copper-cobalt oxide ore is as follows by weight percentage: Cu: 2.5-5.5, Fe: 3.0-5.0, Co: 0.3-1.2, CaO: 1.0-4.0, MgO: 4.0-10.0, SiO2: 46.0-58.

0.

3. The method for treating copper-cobalt oxide ore according to claim 1, characterized in that: In the step 1), the reaction temperature is controlled at 95-105°C, the pressure is 0.05-0.1MPa, the pH is 1.0-2.0, the liquid-solid ratio is 3-5:1, and the SO2 dosage is 24-40Nm 3 / ton of ore, reaction time 2-4h.

4. The method for treating copper-cobalt oxide ore according to claim 1, characterized in that: In the step 2), the process conditions for copper sulfide deposition are: the amount of sulfiding agent added is 0.9-1.2 times the theoretical amount, and the redox potential is controlled at 200-300mv; the process conditions for cobalt sulfide deposition are: the amount of sulfiding agent added is 0.9-1.2 times the theoretical amount, and the redox potential is controlled at -100-100mv.

5. The method for treating copper-cobalt oxide ore according to claim 1, characterized in that: In the step 3), the solution after cobalt precipitation contains 0.1-0.2 g / L of cobalt and 2-4 g / L of iron.

6. The method for treating copper-cobalt oxide ore according to claim 5, characterized in that: The liquid after adsorption contains 0.001-0.005 g / L of cobalt and 2-4 g / L of iron; the analytical solution contains 30-50 g / L of cobalt and 0.1-0.5 g / L of iron; the adsorption process conditions are: pH 0.5, solution flow rate 10 BV / h, analytical solution flow rate 1-4 BV / h, analytical acid is 20-40% sulfuric acid; the analytical solution contains 20-50 g / L of cobalt and 0.1-0.5 g / L of iron.

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