A weak magnetic separation-reverse flotation process based on hydrogen-based mineral phase transformation of pyrolusite

Abstract

The present application relates to the technical field of pyrolusite beneficiation, and particularly relates to a weak magnetic separation-reverse flotation process based on hydrogen-based mineral phase conversion of pyrolusite. In the prior art, the wet reduction process of pyrolusite has the problems of high acid consumption and difficult waste liquid treatment, and the dry reduction process has the problems of easy oxidation of minerals and reduced magnetism in the roasting process. In view of the above problems, the present application first grinds the ore to make most of the ore particles smaller than 38 microns, and then performs hydrogen-based mineral phase conversion suspension roasting, controls the amount of roasting gas, converts the pyrolusite into weakly magnetic and easily acid-soluble rhodochrosite, and makes the quartz lattice transform from alpha SiO2 into beta SiO2. After the gangue minerals are separated by magnetic separation, the magnetic separation concentrate is subjected to flotation to obtain a manganese concentrate. The manganese concentrate has high grade and can be used as a raw material for high-activity leaching and electrolysis of manganese.

Description

Technical Field

[0001] This invention relates to the field of pyrolusite beneficiation technology, specifically to a weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation. Background Technology

[0002] Pyrolusite is an important mineral resource widely used in steel, chemical, and battery industries. However, because pyrolusite is often associated with gangue minerals such as silicoaluminate and hematite, its complex mineral composition and fine particle size pose numerous technical challenges in beneficiation and smelting. Traditional roasting and beneficiation processes are energy-intensive and heavily polluting, failing to meet the requirements of modern green mining development. Traditional reduction processes, such as wet and dry reduction, also have significant drawbacks. Wet reduction typically involves high acid consumption and strong corrosiveness, generating large amounts of heavy metal-containing wastewater that is difficult to treat and puts severe pressure on the environment. Dry reduction, on the other hand, is energy-intensive and requires stringent operating conditions; mineral oxidation and magnetic degradation during roasting limit separation efficiency. Furthermore, high carbon emissions, metal volatilization losses, and waste gas and wastewater discharges during roasting and reduction processes exacerbate environmental pressures and increase production costs. Existing technologies struggle to simultaneously improve resource utilization efficiency while achieving both environmental friendliness and economic viability. To address these challenges, there is an urgent need to develop a new, efficient, energy-saving, and environmentally friendly process to achieve the efficient and clean utilization of soft manganese ore resources and promote the green and sustainable development of the manganese ore beneficiation field.

[0003] Patent CN110129589 A relates to a method for preparing manganese sulfate solution by reduction roasting and leaching of pyrolusite. This method converts manganese dioxide into manganese sulfate solution through low-temperature roasting and acidic leaching for the preparation of manganese-based materials, and reduces costs by incorporating waste electrolyte. This method has simple equipment and low processing costs. However, it requires high-concentration sulfuric acid, resulting in highly corrosive equipment, and the use of carbon powder in roasting increases carbon emissions, leading to high environmental pressure and energy consumption. Patent CN 102861674 B relates to a method for improving the grade of pyrolusite ore by pretreatment with silicate bacteria followed by flotation. This method proposes finely grinding the pyrolusite ore, pretreating it with silicate bacteria, and then performing reverse flotation. This patent can achieve separation of manganese, iron, and gangue minerals to some extent, but the bacterial leaching process is long, has harsh conditions, is difficult to handle complex pyrolusite ores, and suffers from insufficient separation of iron and manganese minerals. Summary of the Invention

[0004] To address the problems existing in current manganese ore beneficiation technologies, this invention provides a weak magnetic separation-reverse flotation process for complex pyrolusite ores based on hydrogen-based mineral phase transformation. The invention mainly comprises five stages: ceramic ball stirred mill grinding, hydrogen-based mineral phase transformation, protective gas cooling, weak magnetic separation, and reverse flotation, to achieve precise mineral phase transformation of pyrolusite from MnO2 to MnO and deep separation from iron-silicon-aluminum gangue minerals.

[0005] This invention provides a weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation, comprising the following steps:

[0006] Step 1: Grinding with a ceramic ball stirred mill: The raw pyrolusite ore enters the ceramic ball stirred mill to obtain a ore material with a particle size of -38μm content of 50%-80%. The corresponding slurry of this ore material is the ceramic ball mill slurry, which is dried to obtain the roasted raw material.

[0007] Step 2 Hydrogen-based mineral phase transformation: The roasted raw material obtained in Step 1 is placed in a suspension roasting furnace for hydrogen-based mineral phase transformation suspension roasting. Pyrolusite is transformed into weakly magnetic and acid-soluble rhodochrosite, and quartz undergoes lattice transformation from α·SiO2 to β·SiO2, yielding mineral phase transformation products.

[0008] Step 3: Protective gas cooling: A protective gas is introduced to cool the mineral phase transformation product, resulting in a cooled product; the protective gas can prevent the mineral phase transformation product from being re-oxidized.

[0009] Step 4: Weak magnetic separation: The cooled product is subjected to weak magnetic separation to obtain magnetic concentrate and magnetic tailings.

[0010] Step 5: Reverse flotation separation: The magnetic concentrate is subjected to reverse flotation to obtain manganese concentrate.

[0011] Furthermore, in step 1, the concentration of the ceramic ball mill slurry is 30% to 50%.

[0012] Furthermore, in step 2, the mineral phase transformation equations are as follows: MnO2+H2→MnO+H2O, α·SiO2→β·SiO2;

[0013] Furthermore, in step 2, the suspension roasting temperature is 600℃~800℃, and the corresponding roasting gas flow rate per ton of roasting raw material at ambient temperature and pressure is 1200 m³ / h. 3 / h-1600m 3 / h, the roasting gas is a mixture of hydrogen and nitrogen, with a hydrogen concentration of 10% to 30%, the suspension roasting time is 20 min to 40 min, and the reducing gas is hydrogen.

[0014] Furthermore, in step 3, the cooling environment is a nitrogen or inert gas atmosphere, the cooling time is 5 min-15 min, and the temperature of the cooled product is ≤70℃.

[0015] Furthermore, in step 4, the magnetic field strength of the weak magnetic separation is 1400 Oe to 3200 Oe, which initially separates manganese concentrate and gangue minerals.

[0016] Furthermore, in step 5, reverse flotation of the magnetic concentrate refers to preparing a reverse flotation slurry from the magnetic concentrate and then entering the reverse flotation operation. This reverse flotation operation includes one roughing stage, one to two cleaning stages, and two to five scavenging stages. A pH adjuster, a combined collector (ZA), and a depressant are added to the reverse flotation slurry, and then the slurry enters the roughing stage. After the roughing stage, a roughing concentrate slurry and a roughing tailings slurry are obtained. The roughing tailings slurry is then subjected to scavenging without the addition of a collector, and gangue minerals are separated after the scavenging stage. A pH adjuster and a combined collector (ZA) are added to the roughing concentrate slurry, and the scavenging stage is then entered into the cleaning stage, whereby the silica-alumina gangue minerals adsorb the collector to achieve reverse flotation. After the cleaning stage, manganese concentrate is obtained.

[0017] Furthermore, in step 5, the pH adjuster includes sodium hydroxide and hydrochloric acid, the combined collector (ZA) is a mixture of sodium oleate and octadecyltrimethylammonium chloride in a mass ratio of 3:1 to 10:1, and the inhibitor includes sodium hexametaphosphate.

[0018] Furthermore, in step 5, the concentration of the reverse flotation slurry during the roughing operation is 35wt% to 55wt%; the materials added per ton of reverse flotation slurry are as follows: sodium hydroxide and hydrochloric acid are added to make the pH of the reverse flotation slurry 8.8 to 9.2; the dosage of combined collector ZA is 100g to 800g, and the dosage of inhibitor sodium hexametaphosphate is 100g to 1000g;

[0019] When entering the fine treatment operation, add a pH adjuster to the roughing concentrate pulp to adjust the pH to 8.8-9.2, and add 20g-200g of combined collector ZA per ton of roughing concentrate pulp.

[0020] Furthermore, in step 5, the grade of the obtained manganese concentrate is higher than 50%, and the manganese recovery rate is higher than 85%.

[0021] Compared with traditional technologies, the weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation, as described in this invention, has the following advantages:

[0022] 1. The present invention uses a ceramic ball stirred mill, which not only effectively avoids the introduction of iron ions during steel ball media grinding, but also obtains grinding products with uniform particle size and suitable for flotation, without over-grinding or under-grinding, and fully liberates manganese oxide and gangue minerals.

[0023] 2. This invention uses suspension roasting technology to perform hydrogen-based mineral phase transformation on pyrolusite. While being green and environmentally friendly, it not only transforms acid- and alkali-insoluble pyrolusite into weakly magnetic and acid-soluble rhodochrosite, but also provides a guarantee for subsequent magnetic separation.

[0024] 3. This invention uses protective gas cooling and introduces inert gas to cool the material, effectively preventing the natural oxidation of newly formed manganese ore in an oxidizing atmosphere, increasing the divalent manganese content in the reduction product, and successfully establishing a cooling and anti-oxidation mechanism.

[0025] 4. This invention employs a combined collector ZA for deep removal of silica-alumina gangue minerals. Through intermolecular synergy and electrostatic adsorption between anions and cations, the agent's effect on Si is further enhanced. 2+ The binding ability of the active sites results in a better collection effect on gangue minerals, and the obtained manganese concentrate can be used as a raw material for highly active leaching electrolytic manganese.

[0026] 5. This invention uses hydrogen-based mineral phase conversion-weak magnetic separation-reverse flotation technology to convert pyrolusite into highly active manganese concentrate that is easy to leach and electrolyze, saving reagent usage for the next leaching process. Furthermore, the use of hydrogen reduction effectively reduces carbon emissions, achieving clean and efficient utilization of pyrolusite mineral resources. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments and accompanying drawings. It should be noted that the embodiments described in this invention are only for further explanation and illustration, and not for limiting their scope of application. All other embodiments obtained by those skilled in the art based on this invention without inventive effort are within the protection scope of this invention.

[0029] The process diagram of this invention is as follows: Figure 1 As shown.

[0030] Example 1

[0031] This embodiment uses a soft manganese ore from a certain region as raw material. The main chemical components are total manganese (TMn) 25.90%, SiO 26.98%, and Al 2O 33.82%. The specific steps are as follows:

[0032] Step 1: Grinding with a ceramic ball stirred mill: The raw pyrolusite ore first enters the ceramic ball stirred mill to obtain ore with a particle size of -38μm content of 72%, and the corresponding slurry concentration of the ore is 38%. After drying, the calcined raw material is obtained.

[0033] Step 2: Hydrogen-based mineral phase conversion: The roasting feedstock is fed into a hydrogen-based mineral phase conversion suspension roaster for suspension roasting. The suspension roasting process is controlled at a temperature of 750℃, with a roasting gas flow rate of 1550 m³ / ton of roasting feedstock. 3The roasting gas is a mixture of hydrogen and nitrogen, with a hydrogen concentration of 15%, and the roasting time is 25 min. The reducing gas is hydrogen. After roasting, mineral phase transformation products are obtained.

[0034] Step 3: Protective gas cooling: After roasting, the mineral phase conversion product is cooled under a nitrogen atmosphere to prevent the rhodochrosite from being oxidized to tetravalent or trivalent manganese. The cooling time is 7 minutes, and the product is cooled to 70°C to obtain the cooled product. The mineral phase conversion rate of rhodochrosite in the cooled product is 99%.

[0035] Step 4: Weak magnetic separation: The cooled product is subjected to weak magnetic separation with a magnetic field strength of 2000 Oe to obtain magnetic concentrate and magnetic tailings.

[0036] Step 5: Reverse Flotation Separation: The magnetic concentrate is converted into a reverse flotation slurry, which enters the reverse flotation process. This process includes one roughing stage, one cleaning stage, and three scavenging stages. The reverse flotation slurry concentration is 42 wt%. Sodium hydroxide and hydrochloric acid are added to adjust the pH to 8.89. A combined collector (ZA dosage 400 g / t, sodium oleate and octadecyltrimethylammonium chloride mass ratio 5:1) and a depressant (sodium hexametaphosphate 500 g / t) are also added before the roughing stage. After the roughing stage, roughing concentrate and roughing tailings slurry are obtained. The roughing tailings slurry is then subjected to scavenging without the addition of a collector, after which gangue minerals are separated. A pH adjuster was added to the roughing concentrate pulp to adjust the pH to 9, followed by the addition of collector ZA 100 g / t. The pulp then entered the cleaning process, where the silica-alumina gangue minerals adsorbed the collector, achieving reverse flotation. After this cleaning process, manganese concentrate was obtained. The manganese concentrate grade was 52.23%, and the recovery rate was 87.42%.

[0037] Example 2

[0038] This embodiment uses a soft manganese ore from a certain region as raw material. The main chemical components are total manganese (TMn) 33.72%, SiO2 5.37%, and Al2O3 6.45%. The specific steps are as follows:

[0039] Step 1: Grinding with a ceramic ball stirred mill: The raw pyrolusite ore first enters the ceramic ball stirred mill to obtain ore with a particle size of -38μm content of 78%, and the corresponding slurry concentration of the ore is 42%. After drying, the calcined raw material is obtained.

[0040] Step 2: Hydrogen-based mineral phase conversion: The roasting feedstock is fed into a hydrogen-based mineral phase conversion suspension roaster for suspension roasting. The suspension roasting process is controlled at a temperature of 700℃, with a roasting gas flow rate of 1300 m³ / ton of roasting feedstock. 3The roasting gas is a mixture of hydrogen and nitrogen, with a hydrogen concentration of 20%, and the roasting time is 30 min. The reducing gas is hydrogen. After roasting, mineral phase transformation products are obtained.

[0041] Step 3: Protective gas cooling: After roasting, the mineral phase conversion product is cooled under a nitrogen atmosphere to prevent the rhodochrosite from being oxidized to tetravalent or trivalent manganese. The cooling time is 15 minutes, and the product is cooled to 40°C to obtain the cooled product. The mineral phase conversion rate of rhodochrosite in the cooled product is 98%.

[0042] Step 4: Weak magnetic separation: The cooled product is subjected to weak magnetic separation with a magnetic field strength of 3000 Oe to obtain magnetic concentrate and magnetic tailings.

[0043] Step 5: Reverse Flotation Separation: The magnetic concentrate is converted into a reverse flotation slurry, which enters the reverse flotation process. This process includes one roughing stage, one cleaning stage, and four scavenging stages. The reverse flotation slurry concentration is 35 wt%. Sodium hydroxide and hydrochloric acid are added to adjust the pH to 8.88. A combined collector (ZA dosage 600 g / t, sodium oleate and octadecyltrimethylammonium chloride mass ratio 7:1) and a depressant (sodium hexametaphosphate 400 g / t) are also added before the slurry enters the roughing stage. After the roughing stage, roughing concentrate and roughing tailings slurry are obtained. The roughing tailings slurry is then subjected to scavenging without the addition of a collector, after which gangue minerals are separated. A pH adjuster was added to the roughing concentrate pulp to adjust the pH to 9, followed by the addition of collector ZA 200 g / t. The pulp then entered the cleaning process, where the silica-alumina gangue minerals adsorbed the collector, achieving reverse flotation. After this cleaning process, manganese concentrate was obtained. The manganese concentrate grade was 54.28%, and the recovery rate was 89.30%.

[0044] Example 3

[0045] This embodiment uses a soft manganese ore from a certain region as raw material. The main chemical components are total manganese (TMn) 25.88%, SiO2 10.82%, and Al2O3 4.36%. The specific steps are as follows:

[0046] Step 1: Grinding with a ceramic ball stirred mill: The raw pyrolusite ore first enters the ceramic ball stirred mill to obtain ore with a particle size of -38μm content of 80%, and the corresponding slurry concentration of the ore is 35%. After drying, the calcined raw material is obtained.

[0047] Step 2: Hydrogen-based mineral phase conversion: The roasting feedstock is fed into a hydrogen-based mineral phase conversion suspension roaster for suspension roasting. The suspension roasting process is controlled at a temperature of 800℃, with a roasting gas flow rate of 1600 m³ / ton of roasting feedstock. 3The roasting gas is a mixture of hydrogen and nitrogen, with a hydrogen concentration of 30%, and the roasting time is 20 min. The reducing gas is hydrogen. After roasting, mineral phase transformation products are obtained.

[0048] Step 3: Protective gas cooling: After roasting, the mineral phase conversion product is cooled under a nitrogen atmosphere to prevent rhodochrosite from being oxidized to tetravalent or trivalent manganese. The cooling time is 10 minutes, and the product is cooled to 60°C to obtain the cooled product. The mineral phase conversion rate of rhodochrosite in the cooled product is 97%.

[0049] Step 4: Weak magnetic separation: The cooled product is subjected to weak magnetic separation with a magnetic field strength of 2500 Oe to obtain magnetic concentrate and magnetic tailings.

[0050] Step 5: Reverse Flotation Separation: The magnetic concentrate is converted into a reverse flotation slurry, which enters the reverse flotation process. This process includes one roughing stage, two cleaning stages, and two scavenging stages. The reverse flotation slurry concentration is 45 wt%. Sodium hydroxide and hydrochloric acid are added to adjust the pH to 9.16. A combined collector (ZA dosage 700 g / t, sodium oleate and octadecyltrimethylammonium chloride mass ratio 9:1) and a depressant (sodium hexametaphosphate 400 g / t) are also added before the roughing stage. After the roughing stage, a roughing concentrate slurry and a roughing tailings slurry are obtained. The roughing tailings slurry is then subjected to scavenging without the addition of a collector, after which gangue minerals are separated. A pH adjuster was added to the roughing concentrate pulp to adjust the pH to 9. In the first stage of cleaning, collector ZA 100 g / t was added, and in the second stage, collector ZA 50 g / t was added. The cleaning process then proceeded, allowing the silica-alumina gangue minerals to adsorb the collector and achieve reverse flotation. After this cleaning process, manganese concentrate was obtained. The manganese concentrate grade was 50.31%, and the recovery rate was 86.93%.

[0051] Example 4

[0052] This embodiment uses a soft manganese ore from a certain region as raw material. The main chemical components are total manganese (TMn) 32.15%, SiO2 12.79%, and Al2O3 5.56%. The specific steps are as follows:

[0053] Step 1: Grinding with a ceramic ball stirred mill: The raw pyrolusite ore first enters the ceramic ball stirred mill to obtain ore with a particle size of -38μm content of 68%, and the corresponding slurry concentration of the ore is 48%. After drying, the calcined raw material is obtained.

[0054] Step 2: Hydrogen-based mineral phase conversion: The roasting feedstock is fed into a hydrogen-based mineral phase conversion suspension roaster for suspension roasting. The suspension roasting process is controlled at a temperature of 650℃, with a roasting gas flow rate of 1450 m³ / ton of roasting feedstock. 3The roasting gas is a mixture of hydrogen and nitrogen, with a hydrogen concentration of 15%, and the roasting time is 35 min. The reducing gas is hydrogen. After roasting, mineral phase transformation products are obtained.

[0055] Step 3: Protective gas cooling: After roasting, the mineral phase conversion product is cooled under a nitrogen atmosphere to prevent the rhodochrosite from being oxidized to tetravalent or trivalent manganese. The cooling time is 8 minutes, and the product is cooled to 50°C to obtain the cooled product. The mineral phase conversion rate of rhodochrosite in the cooled product is 98%.

[0056] Step 4: Weak magnetic separation: The cooled product is subjected to weak magnetic separation with a magnetic field strength of 2000 Oe to obtain magnetic concentrate and magnetic tailings.

[0057] Step 5: Reverse Flotation Separation: The magnetic concentrate is converted into a reverse flotation slurry, which enters the reverse flotation process. This process includes one roughing stage, one cleaning stage, and two scavenging stages. The reverse flotation slurry concentration is 52 wt%. Sodium hydroxide and hydrochloric acid are added to adjust the pH to 8.97, along with a combined collector (600 g / t of ZA, with a sodium oleate and octadecyltrimethylammonium chloride mass ratio of 7:1) and a depressant (700 g / t of sodium hexametaphosphate). This slurry then enters the roughing stage. After roughing, roughing concentrate and roughing tailings slurry are obtained. The roughing tailings slurry is then scavenged without collector addition, separating gangue minerals. A pH adjuster is added to the roughing concentrate slurry to adjust the pH to 9. 200 g / t of collector ZA is added to the cleaning stage, allowing the silica-alumina gangue minerals to adsorb the collector and achieve reverse flotation. This cleaning stage yields manganese concentrate. The manganese concentrate grade is 54.11%, and the recovery rate is 88.34%.

[0058] Comparative Example 1

[0059] Compared to Example 1, the difference lies in that step 3 does not use protective gas cooling, but only air cooling; the remaining steps are the same as in Example 1. In step 3, the conversion rate of manganese ore was only 51%, and in step 5, the grade and recovery rate of manganese concentrate were only 44.32% and 68.34%, respectively. The possible reason is that divalent manganese is oxidized to hypervalent manganese during the cooling process, which alters its magnetic and surface properties, thereby reducing the iron-manganese separation in the magnetic separation process and the adsorption effect of flotation reagents in the flotation process.

[0060] Comparative Example 2

[0061] Compared to Example 2, the difference lies in that step 4 does not use the novel collector used in this invention, but only the conventional flotation collector sodium oleate is used; the remaining steps are the same as in Example 2. In step 5, the manganese concentrate grade is only 41.21%, with a large amount of silica-bearing gangue minerals entering the concentrate.

Claims

1. A weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation, characterized in that, Includes the following: Step 1: Grinding with a ceramic ball stirred mill: The raw pyrolusite ore is fed into a ceramic ball stirred mill to obtain a ore material with a particle size of -38μm content of 50%~80%. The slurry corresponding to this ore material is the ceramic ball mill slurry, which is dried to obtain the roasting raw material. Step 2 Hydrogen-based mineral phase transformation: The roasting raw material obtained in Step 1 is placed in a suspension roasting furnace for hydrogen-based mineral phase transformation suspension roasting. The pyrolusite is transformed into weakly magnetic and acid-soluble rhodochrosite, and the quartz undergoes a lattice transformation from α•SiO2 to β•SiO2, thus obtaining the mineral phase transformation product. Step 3: Protective gas cooling: Introduce protective gas to cool the mineral phase transformation product and obtain the cooled product; Step 4: Weak magnetic separation: The cooled product is subjected to weak magnetic separation to obtain magnetic concentrate and magnetic tailings; Step 5: Reverse flotation separation: The magnetic concentrate is subjected to reverse flotation to obtain manganese concentrate; In step 2, the suspension roasting temperature is 600℃~800℃, and the corresponding roasting gas flow rate per ton of roasting raw material at ambient temperature and pressure is 1200 m³ / h. 3 / h~1600m 3 / h, the roasting gas is a mixture of hydrogen and nitrogen, with a hydrogen concentration of 10%~30%, the suspension roasting time is 20min~40min, and the reducing gas is hydrogen.

2. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 1, characterized in that, In step 1, the concentration of the ceramic ball mill slurry is 30%~50%.

3. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 1, characterized in that, In step 3, the cooling environment is a nitrogen or inert gas atmosphere, the cooling time is 5 min to 15 min, and the temperature of the cooled product is ≤70℃.

4. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 1, characterized in that, In step 4, the magnetic field strength of the weak magnetic separation is 1400 Oe to 3200 Oe, which initially separates manganese concentrate and gangue minerals.

5. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 1, characterized in that, In step 5, reverse flotation of magnetic concentrate refers to preparing reverse flotation slurry from magnetic concentrate and then entering the reverse flotation operation. The reverse flotation operation includes one roughing stage, one to two cleaning stages, and two to five scavenging stages. A pH adjuster, a combined collector ZA, and a depressant are added to the reverse flotation slurry, which is then used for roughing. After the roughing operation, roughing concentrate and roughing tailings slurry are obtained. The roughing tailings slurry is then subjected to scavenging without the addition of a collector, after which gangue minerals are separated. A pH adjuster and a combined collector ZA are added to the roughing concentrate slurry, which is then used for cleaning, where the silica-alumina gangue minerals adsorb the collector to achieve reverse flotation. After the cleaning operation, manganese concentrate is obtained.

6. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 5, characterized in that, In step 5, the pH adjuster used in the reverse flotation operation includes sodium hydroxide and hydrochloric acid, the combined collector ZA is a mixture of sodium oleate and octadecyltrimethylammonium chloride in a mass ratio of 3:1 to 10:1, and the inhibitor includes sodium hexametaphosphate.

7. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 5, characterized in that, In step 5, the concentration of the reverse flotation pulp is 35wt%~55wt% when entering the roughing operation; the following materials are added per ton of reverse flotation pulp: sodium hydroxide and hydrochloric acid are added to make the pH of the reverse flotation pulp 8.8~9.2; the dosage of combined collector ZA is 100g~800g, and the dosage of inhibitor sodium hexametaphosphate is 100g~1000g.

8. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 5, characterized in that, In step 5, when entering the fine separation operation, a pH adjuster is added to the roughing concentrate slurry to adjust the pH to 8.8~9.2, and 20g~200g of combined collector ZA is added per ton of roughing concentrate slurry.

9. The weak magnetic separation-reverse flotation process for pyrolusite based on hydrogen-based mineral phase transformation according to claim 5, characterized in that, In step 5, the grade of the manganese concentrate obtained is higher than 50%, and the manganese recovery rate is higher than 85%.

Images