A method for beneficiating high-clay low-grade manganese carbonate ore

Abstract

The present invention discloses a beneficiation method for high-clay low-grade manganese carbonate ore, wherein the adjusting agent polyepoxysuccinic acid (PESA) is first prepared into a solution; the raw ore is added into a mill, and the raw ore is high-clay low-grade manganese carbonate ore. At the same time, 200-800 g / t of PESA is added into the mill, and the raw ore is ground, and the grinding fineness of 0.075 mm accounts for 54%-70%; then, the grinding product enters the magnetic separation operation, and after a rough and sweep separation process is carried out by a high-gradient magnetic separator, a comprehensive manganese concentrate with high grade and high recovery rate is obtained. The present invention can achieve the purpose of green environmental protection, efficient short process, and reducing the discharge of electrolytic manganese slag at the source.

Description

Technical Field

[0001] The invention relates to a beneficiation method for high-clay low-grade manganese carbonate ore, and in particular to a green and environmentally friendly, efficient and short-process beneficiation method for reducing the emission of manganese slag at the source. Background Art

[0002] my country's manganese ore reserves are 2.1 billion tons, the main type of ore is manganese carbonate, with a grade of less than 30%, and the reserves account for 26% of the world. Guizhou has 839 million tons, accounting for about 40% of the country; Guangxi has 476 million tons, accounting for 22.7% of the country. Tongren City, Guizhou has proven manganese ore resources of 740 million tons, accounting for 35.2% of the country and 88.2% of the province. There are 4 super-large manganese deposits of more than 100 million tons (there are 13 in the world) and 1 super-large manganese-rich deposit. The ore grade is between 11% and 22%, with an average grade of about 16%. In actual production, the grade is about 14%. Low-grade manganese carbonate ore has the characteristics of "poor, mixed, and fine", and has ore characteristics such as medium-high iron and high clay. The production of 1 ton of metallic manganese produces 8 to 10 tons of manganese slag. The annual increase in manganese slag in the country exceeds 10 million tons, and the cumulative stockpile of manganese slag exceeds 150 million tons. The manganese slag in the "Manganese Triangle" area increases by more than one million tons each year, and the cumulative stockpile of slag in the warehouse exceeds 12 million tons. The manganese slag in the warehouse not only occupies a large amount of land, but also has serious water accumulation and fluidization due to long-term operation. There are serious safety hazards during the rainy season, and heavy metal ions cause serious pollution to downstream water bodies. Therefore, in order to reduce the pressure of slag storage, reduce the cost of electrolytic manganese operations, and improve the comprehensive recovery rate of manganese, it is urgent to adopt appropriate physical methods to efficiently separate manganese-containing minerals from silicon-containing and other gangue minerals, so as to achieve the purpose of green reduction of electrolytic manganese slag emissions at the source.

[0003] At present, the emission reduction technologies for low-grade manganese carbonate ore mainly include physical beneficiation and chemical beneficiation. Due to the high production cost and environmental pollution of chemical beneficiation, chemical beneficiation is not recommended. Physical beneficiation includes washing, re-selection and flotation. Among them, flotation is the use of chemical agents to regulate the mineral interface to achieve the separation of rhodochrosite and gangue minerals. Compared with other physical beneficiation methods, this method has a relatively high production cost, and flotation agents will have a certain impact on electrolytic manganese operations. Washing and re-selection can only play the role of throwing away surrounding rocks or muddy materials in the beneficiation of manganese carbonate ore to restore the geological grade, but rhodochrosite is brittle and easy to mud, thereby reducing the comprehensive recovery rate of manganese. In summary, after the low-grade manganese carbonate ore is fully dissociated, the weakly magnetic mineral rhodochrosite and non-magnetic gangue minerals are separated in a strong magnetic field by using the difference in mineral magnetic properties. The use of strong magnetic separation is an effective method. Since rhodochrosite is brittle and easy to be muddied, and the ore also contains a large amount of clay minerals, it is easy to cover the rhodochrosite interface or carry manganese ore mud, which not only reduces the capture rate of rhodochrosite by magnetic media, but also some clay minerals adhere to the surface of magnetic minerals and are selected into the concentrate product together, thereby reducing the grade and recovery rate of magnetically separated manganese concentrate. Therefore, the key to improving the beneficiation index of high-clay manganese carbonate ore is to effectively improve the dispersion characteristics of the slurry, realize the dispersion between mineral particles, improve the fluidity of the viscous slurry, and improve the interference of the ore mud on the magnetism of rhodochrosite. In short, in order to reduce the pressure of electrolytic manganese slag disposal, it is necessary to achieve the reduction of electrolytic manganese slag source emissions by physical methods. The existing technology mainly has the following problems: complex process, addition of multiple chemical agents, low manganese recovery rate or manganese slag source reduction. Summary of the invention

[0004] The purpose of the present invention is to provide a beneficiation method for high-clay low-grade manganese carbonate ore, so as to achieve the purpose of green environmental protection, high efficiency and short process, and reduce the emission of manganese slag at the source.

[0005] In order to achieve the above object, the solution of the present invention is:

[0006] A method for beneficiating high-clay low-grade manganese carbonate ore, the steps of which are as follows:

[0007] In the first step, polyepoxysuccinic acid (PESA) is prepared into a solution, and c is 0.004 g / L;

[0008] The second step is to add the raw ore into the mill. The raw ore is a high-clay low-grade manganese carbonate ore with a clay mineral content of 18% to 24% and a manganese grade of 10% to 13%. At the same time, 200 to 800 g / t of PESA is added to the mill to grind the raw ore. The grinding fineness of -0.075 mm accounts for 54% to 70%.

[0009] In the third step, the grinding products of the second step enter the magnetic separation operation. After a roughing and sweeping separation process by a high gradient magnetic separator, a comprehensive manganese concentrate with high grade and high recovery rate is obtained. The roughing magnetic field strength range is 0.9-1.1T, the sweeping magnetic field strength range is 1.3-1.5T, the magnetic medium of the high gradient magnetic separator is 2.5mm, and the magnetic separation pulsation frequency is 100-150r / min.

[0010] After adopting the above scheme, the present invention provides a green, efficient and short-process physical method to achieve source reduction of electrolytic manganese slag emissions in Tongren City, aiming at the problems that high-clay low-grade manganese carbonate ore in Tongren City is prone to mudification, ore mud entrainment and covering during the grinding process, which leads to low ore dressing efficiency, difficulty in obtaining high-grade manganese concentrate and low recovery rate. The present invention adopts PESA as a regulator. PESA is a phosphorus-free, non-nitrogen and biodegradable green and environmentally friendly water-soluble polymer. It has a strong chelating ability for metal ions such as calcium, magnesium and iron. A certain proportion (200-800 g / t) of PESA is added to the mill to grind low-grade manganese carbonate ore, effectively improving the slurry dispersion characteristics, achieving dispersion between mineral particles, improving the fluidity of the viscous slurry, reducing the covering or entrainment of clay minerals on rhodochrosite, effectively inhibiting the agglomeration between particles, reducing the mudification degree, improving the interference of mudification on the magnetic separation of rhodochrosite, forming a slurry with effective monomer dissociation of minerals, thereby helping to improve the beneficiation index of magnetically separated manganese concentrate, and then through high-gradient magnetic separation, the grade and recovery rate of the comprehensive manganese concentrate can be significantly improved. Specifically, by adding a specific proportion of PESA in the grinding process and combining a roughing and sweeping magnetic separation process, the manganese grade can be increased by 6-7 percentage points, the manganese recovery rate is 87%-93%, and the source emission reduction is achieved by 40%-50%. In summary, the entire processing flow of the present invention is short and efficient, and the grade of the magnetic separation tailings is low. While ensuring the efficient recovery of manganese-containing minerals in the ore, it can achieve green and efficient source reduction of low-grade manganese carbonate ore.

[0011] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a simplified process flow diagram of the present invention. DETAILED DESCRIPTION

[0013] like Figure 1As shown, the present invention is a beneficiation method for high-clay type low-grade manganese carbonate ore. The present invention is mainly suitable for beneficiation of raw ore with a clay mineral content of 18% to 24% and a grade of 10% to 13%. First, polyepoxysuccinic acid (PESA) is prepared into a solution (c = 0.004g / L). Then, the raw ore (high-clay type low-grade manganese carbonate ore) is added to the mill. At the same time, PESA is also added to the mill. 200 to 800g PESA is added to each ton of raw ore. The ore is ground in the mill, and the grinding fineness of -0.075mm accounts for 54% to 70%. Then, the grinding product enters the magnetic separation operation, and after a high-gradient magnetic separator (magnetic medium 2.5mm, magnetic separation pulsation impulse 100 to 150r / min) is used for a rough (0.9 to 1.1T) and a sweep (1.3 to 1.5T) separation process, a high-grade, high-recovery comprehensive manganese concentrate is obtained.

[0014] In order to prove that adding the adjusting agent PESA into the mill and grinding it together with high-clay low-grade manganese carbonate ore can reduce the degree of ore muddiness and significantly improve the separation index of magnetic concentrate, comparative tests were carried out before and after PESA was added to the mill and at the addition point. The results are shown in Tables 1 and 2.

[0015] First, adding PESA to the mill can slow down the sliming of manganese carbonate ore. As can be seen from Table 1, after adding PESA for 3 minutes, the yield of particle size +20μm-38μm decreased by about 3 percentage points (from 49.31% to 46.13%), while the yield of particle size -20μm decreased by nearly 2 percentage points (from 38.55% to 36.74%).

[0016] Secondly, it can be seen from Table 2 that adding PESA during the grinding process can improve the beneficiation index of magnetically separated manganese concentrate, especially the recovery rate is significantly increased by 17.54%; after adding the agent for a period of time after grinding and then performing magnetic separation, the recovery rate is increased by 11.09%. It shows that the present invention has a good gain effect in the magnetic separation process of low-grade manganese carbonate ore. By comparing the magnetic separation test results of the PESA addition point, it is concluded that adding PESA in the mill has a good benefit, which is also an important innovation point of the present invention.

[0017] Table 1 Comparison of particle size composition before and after PESA was added to the mill

[0018]

[0019] Table 2 Comparative test of reagent addition points

[0020]

[0021] Tongren City is rich in manganese carbonate ore, with a resource reserve of more than 700 million tons. The ore contains a certain amount of gangue minerals such as quartz and clay minerals. Polyepoxysuccinic acid (PESA) is an effective descaling agent with low cost, convenient use of water-soluble polymers, biodegradability, and green environmental protection. The agent can effectively react with metal ions such as calcium, magnesium and iron to generate water-soluble compounds, effectively solve the problem of scale formation in the recycling of backwater, and can reduce the inevitable ions of calcium, magnesium and iron in the electrolytic manganese operation, which is conducive to improving the electrolytic operation environment of the subsequent manganese concentrate. The present invention uses PESA as a regulator, which can effectively reduce the mudification phenomenon in the grinding operation, reduce the cover or entrainment of clay minerals on rhodochrosite, avoid the coarse phenomenon caused by adhesion to the surface of the target mineral in magnetic separation, and effectively improve the grade and recovery rate of magnetic separation concentrate; improve the dispersion characteristics of the ore pulp, which is conducive to the capture efficiency of the magnetic medium to rhodochrosite, more efficiently select the target mineral, reduce energy consumption, and have important significance for the development and utilization of high-clay low-grade manganese carbonate ore.

[0022] Embodiment 1:

[0023] The manganese-containing minerals in the representative ore sample I of Tongren City are calcium rhodochrosite and manganese dolomite, and the gangue minerals are mainly clay minerals, quartz, dolomite, albite, and a small amount of calcite and pyrite. The manganese grade of the original ore is 11.43%, and the clay minerals mainly include illite and a small amount of chlorite, with a content of 23.10%. The ore samples are crushed and screened to -2mm and then mixed. 200g of the mixed ore samples are taken for grinding, the grinding concentration is 66.7%, PESA 0~800g / t, and the grinding fineness of -0.075mm accounts for 54.53%. A magnetic separation (1.0T) test is carried out in a Slon-100 high gradient magnetic separator. The results are shown in Table 3. Due to the improvement of PESA on the flow characteristics of the ore pulp, the yield of manganese concentrate increased to 50.30% to 51.08%, an increase of about 5 percentage points; the manganese recovery rate reached 84.25% to 87.71%, an increase of 7.01 to 7.75 percentage points. Under the condition of 800g / t PESA dosage, a one-coarse (1.0T) and one-sweep (1.4T) magnetic separation process test was carried out. The test results are shown in Table 4. A comprehensive manganese concentrate with a manganese grade of 16.92% and a recovery rate of 93.61% can be obtained, in which the manganese content in the magnetic separation tailings is reduced to 1.66%, and the tailings throwing rate is 41.02%, which has achieved a good green source reduction of manganese slag emissions.

[0024] Table 3 Comparative test of representative ore samples in Tongren City Ⅰ

[0025]

[0026]

[0027] Table 4 Magnetic separation optimization test of representative ore samples in Tongren City I

[0028]

[0029] Embodiment 2:

[0030] The manganese-containing minerals in the representative ore sample II of Tongren City are calcium rhodochrosite and manganese dolomite, and the main gangue minerals are quartz, clay minerals, dolomite, albite, a small amount of pyrite and gypsum. The manganese grade of the original ore is 10.66%, and the clay mineral is mainly illite, which contains 19.30%. The ore samples were crushed and screened to -2 mm and then mixed. 200 g of the mixed ore sample was taken for grinding. The grinding concentration was 66.7%, PESA was 0-800 g / t, and the grinding fineness was -0.075 mm, accounting for 62.71%. A magnetic separation (1.0 T) test was carried out in a Slon-100 high gradient magnetic separator. The results are shown in Table 5. Compared with not adding PESA, adding PESA during grinding can significantly improve the beneficiation index of magnetically separated manganese concentrate. The manganese concentrate yield was 44.40%-47.50%, and the yield was increased by 4.57%-7.67%; the manganese recovery rate was 73.87%-79.88%, and the recovery rate was increased by 10.25%-16.26%. Under the condition of PESA dosage of 600g / t, a one-rough (1.0T) and one-sweep (1.4T) magnetic separation process test was carried out. The test results are shown in Table 6. A comprehensive manganese concentrate with a grade of 17.92% and a recovery rate of 92.92% can be obtained. The manganese content in the magnetic separation tailings is reduced to 2.01%, and the tailings discarding rate is 40.46%. It can also achieve the green source reduction of manganese slag emissions.

[0031] Table 5 Comparative test of representative ore samples II in Tongren City

[0032]

[0033] Table 6 Magnetic separation optimization test of representative ore samples II in Tongren City

[0034]

[0035] Embodiment 3:

[0036] The manganese-containing mineral in the representative ore sample III of Tongren City is calcium rhodochrosite, and the gangue minerals are mainly quartz, clay minerals, plagioclase, pyrite, and a small amount of iron dolomite, gypsum, calcite and siderite. The grade of the original ore is 12.66%, and the clay minerals mainly include illite and a small amount of illite / montmorillonite mixed layer, chlorite and kaolinite, with a content of 18.91%. The ore sample is crushed and screened to -2mm and then mixed. 200g of the mixed ore sample is taken for grinding, the grinding concentration is 66.7%, PESA 0~800g / t, and the grinding fineness is -0.075mm, accounting for 70.02%. A magnetic separation (1.0T) test is carried out in a Slon-100 high gradient magnetic separator. The results are shown in Table 7. Compared with not adding the adjusting agent PESA, adding PESA during grinding can significantly improve the beneficiation index of magnetic separation manganese concentrate. Under the condition of PESA dosage of 400g / t, a one-coarse (1.0T) and one-sweep (1.4T) magnetic separation process test was carried out. The test results are shown in Table 8. A comprehensive manganese concentrate with a grade of 18.04% and a recovery rate of 87.78% can be obtained. For low-grade manganese carbonate ore with complex clay mineral composition, a tailings discarding rate of 38.51% can also be achieved.

[0037] Table 7 Comparative test of representative ore samples in Tongren City

[0038]

[0039] Table 8 Magnetic separation optimization test of representative ore samples in Tongren City

[0040]

[0041]

[0042] The above are preferred embodiments of the present invention, but they do not limit the present invention. Any modifications, equivalent substitutions and improvements made by any technical personnel in this field without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for beneficiating high-clay low-grade manganese carbonate ore, characterized in that Here are the steps: The first step is to prepare polyepoxysuccinic acid PESA into a solution; The second step is to add the raw ore into the mill. The raw ore is a high-clay low-grade manganese carbonate ore with a clay mineral content of 18% to 24% and a manganese grade of 10% to 13%. At the same time, 200 to 800 g / t of PESA is added to the mill to grind the raw ore. The grinding fineness of -0.075 mm accounts for 54% to 70%. In the third step, the grinding products of the second step enter the magnetic separation operation. After a roughing and sweeping separation process using a high gradient magnetic separator, a comprehensive manganese concentrate with high grade and high recovery rate is obtained.

2. The method for beneficiating a high-clay low-grade manganese carbonate ore according to claim 1, characterized in that: In the first step, the PESA solution was prepared with a concentration c of 0.004 g / L.

3. The beneficiation method of a high-clay low-grade manganese carbonate ore according to claim 1, characterized in that: The third step is to use a roughing magnetic field strength range of 0.9 to 1.1 T, a scanning magnetic field strength range of 1.3 to 1.5 T, a high gradient magnetic separator magnetic medium of 2.5 mm, and a magnetic separation pulsation frequency of 100 to 150 r / min.

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