Method for improving galena flotation recovery rate under grinding system and verification method thereof

Abstract

The invention relates to a method for improving the galena flotation recovery rate under a grinding system and a verification method thereof, and belongs to the technical field of engineering. A hexagonal prism-shaped grinding medium is adopted to replace a traditional spherical medium to grind galena particles, and under the same crushing result, the galena flotation recovery rate is increased. The hexagonal prism-shaped grinding medium is adopted to grind galena, the medium is in linear contact and surface contact with minerals in the ore grinding process, the effect of grinding the galena can be effectively achieved, meanwhile, the over-crushing phenomenon of the galena is reduced, and ground galena particles have large elongation and certain edges and sharp corners, so that the grinding efficiency is improved, and the grinding quality of the galena is improved. In the flotation process, a bubble hydration layer can be rapidly punctured, the adhesion time of galena mineral particles and bubbles is shortened, and finally the recovery rate of galena is increased.

Description

Technical Field

[0001] This invention relates to a method for improving the flotation recovery rate of galena in a grinding system and its verification method, belonging to the field of engineering technology. Background Technology

[0002] In grinding operations, the type of grinding media has a significant impact on the grinding effect of minerals, especially the shape of the media.

[0003] Research on grinding media of different shapes has been ongoing both domestically and internationally, including rod-shaped, spherical, tetrahedral, short cylindrical, conical, truncated conical, elliptical, teardrop-shaped, capsule-shaped, octahedral, and hexagonal prism shapes. Short cylindrical and truncated conical shapes have been the most studied, as they combine point and line contact with mineral particles, effectively preventing over-grinding. These two shapes have been successfully applied in the fine grinding of phosphate, nickel, and lead-zinc ores with good grinding results. However, during use, the top and bottom edges of short cylindrical and truncated conical media experience stress concentration, leading to excessive wear and ultimately causing the worn media to tend towards a circular shape.

[0004] Currently, the most common grinding media shape in mineral processing plants is still spherical, while for brittle and fragile ores, such as cassiterite, some plants and mines will choose rod-shaped media.

[0005] The contact between the spherical medium and the mineral particles is point contact. Therefore, the particles will be subjected to a large destructive force the moment they come into contact with the steel ball. Some particles will form penetrating fragments along the cleavage plane. As a result, the selective dissociation effect of the steel ball on the mineral is poor, which may cause the mineral to be over-ground, producing a large number of (ultra)fine and highly spherical pulverized particles.

[0006] Because rod-shaped grinding media are prone to breakage and disorder during the grinding process, the machine must be shut down for repairs, which seriously affects the production process. At the same time, changing and adding rods is also time-consuming and labor-intensive, which makes spherical grinding media still the most important grinding media at present.

[0007] Galena is the most important mineral raw material for lead refining, and silver-bearing galena is also an important raw material for silver refining. Lead has wide applications in metallurgy, national defense, science and technology, and the electronics industry. Galena is a cubic crystal, brittle, and has a Mohs hardness of 2.5, making it a relatively soft mineral. During grinding with spherical media, the point contact impact of the steel balls can easily lead to over-grinding, thus affecting the galena recovery rate. Rod-shaped media and short cylindrical or truncated conical media also suffer from drawbacks in galena grinding, including severe media wear and the need for rod replacement and addition. Summary of the Invention

[0008] This invention addresses the issue that in existing technologies, the shape of grinding media only affects the crushing result of minerals. It provides a method where, under the same crushing result, different grinding media directly impact the subsequent flotation process. This invention uses hexagonal prism-shaped grinding media to grind galena. Under the same crushing result as spherical grinding media, this directly improves the flotation recovery rate in the subsequent flotation process. This invention is achieved through the following technical solution.

[0009] A method for improving the flotation recovery rate of galena in a grinding system is proposed, which uses hexagonal prism-shaped grinding media instead of traditional spherical media to grind galena particles, thereby improving the flotation recovery rate of galena under the same grinding results.

[0010] The hexagonal prism-shaped grinding media grinds galena particles down to 200 mesh with a yield of 60%-80%.

[0011] The hexagonal prism-shaped grinding media is made of cast iron, the same material as conventional cast balls, with a length-to-height ratio of 1 / 3.

[0012] A verification method for improving the flotation recovery rate of galena in a grinding system, comprising the following steps: (1) Select appropriate hexagonal prism or other shapes of grinding media according to the size of the galena particles being ground, and select the required grinding environment (dry grinding or wet grinding) according to the test requirements. (2) Weigh several galena ore samples and grind them in a mill with hexagonal prism and other grinding media for 2 min, 4 min, 6 min, 8 min and 10 min respectively. Then, screen the discharged ore after grinding and calculate the -200 mesh yield corresponding to the two types of media at different grinding times. (3) Based on the grinding time as the x-axis and the -200 mesh yield corresponding to different grinding times as the y-axis, draw and simulate the relationship between grinding time and -200 mesh yield under two different shaped media. (4) Based on the relationship diagram, select the grinding time corresponding to the -200 mesh yield of 60%, 65%, 70%, 75%, and 80%, respectively, which is t. 其它60% t 其它65% t 其它70% t 其它75% t 其它80% , and t 六60% t 六65% t 六70% t 六75% t 六80% ; (5) Weigh out several portions of raw galena ore samples and grind them separately using hexagonal prism-shaped grinding media. 六60% t 六65% t 六70% t六75% t 六80% And grinding with other shapes of grinding media respectively. 其它60% t 其它65% t 其它70% t 其它75% t 其它80% Grind the ore; (6) Different ground ores were transferred to flotation cells for flotation. The reagent system was kept consistent during the flotation process. The flotation recovery rate of galena was calculated separately. It was verified that under the same crushing result, that is, the same grinding fineness, the flotation recovery rate obtained by using hexagonal prism grinding media was the highest and the flotation effect was the best.

[0013] The calculated recovery rate of galena flotation is: After flotation, the mass of the flotation concentrate was weighed, and the grades of the flotation tailings and flotation concentrate were analyzed separately to accurately derive the Pb grade in each batch of raw ore. The Pb grade in the raw ore was then calculated using the formula: The calculated recovery rate of galena flotation is: After flotation, the mass of the flotation concentrate was weighed, and the grades of the flotation tailings and flotation concentrate were analyzed separately to accurately derive the Pb grade in each batch of raw ore. The Pb grade in the raw ore was then calculated using the formula: (1); in, This represents the Pb grade in the raw ore. The grade of Pb in the concentrate. The grade of Pb in the tailings. For the yield of concentrate, The yield of tailings; Calculate the recovery rate for each group of galena flotation: (2) in, The recovery rates of lead ore flotation at different yields below -200 mesh were calculated. i Different yields for -200 mesh.

[0014] The beneficial effects of this invention are: (1) The present invention uses a hexagonal prism-shaped grinding media to grind galena. During the grinding process, the media contacts the mineral in the form of line contact and surface contact, which can effectively play the role of grinding galena while reducing the over-grinding phenomenon of galena. Furthermore, the ground galena particles have a large elongation rate and certain edges and sharp corners, which can quickly pierce the bubble hydration layer during the flotation process, shorten the adhesion time between galena mineral particles and bubbles, and ultimately improve the recovery rate of galena.

[0015] (2) The present invention uses hexagonal prism-shaped grinding media to grind galena, thereby increasing the surface roughness, angularity and elongation of the galena particles after grinding, and ultimately improving the flotation recovery rate of galena.

[0016] (3) This invention has the advantages of small workload, convenient medium addition, low labor intensity and high galena recovery rate, which can bring great innovation to engineering practice and scientific research, and further improve the flotation recovery rate of galena.

[0017] (4) The verification method of the present invention has a simple, convenient, fast and easy-to-understand calculation process, which is conducive to the learning, use and promotion of other engineering technicians.

[0018] (5) This invention makes up for the shortcomings of traditional spherical media in the grinding process, and can improve the flotation recovery rate of galena, improve the comprehensive utilization of mineral resources, and improve the efficiency of enterprises. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the verification method of the present invention; Figure 2 This is a schematic diagram of the hexagonal prism-shaped grinding media structure of the present invention; Figure 3 This is the grinding simulation curve of the hexagonal prism-shaped grinding media during the verification process of the embodiments of the present invention; Figure 4 These are the grinding simulation curves of the spherical grinding media during the verification process of this invention embodiment; Figure 5 This is a flowchart illustrating the flotation process during the verification of an embodiment of the present invention. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0021] Example 1 This example uses galena ore from a lead-zinc mine in a certain region of Northwest China for illustration.

[0022] The method for improving the flotation recovery rate of galena in this grinding system is to use hexagonal prism-shaped grinding media instead of traditional spherical media to grind galena particles. Under the same grinding results, the flotation recovery rate of galena will be improved. The yield of galena particles of -200 mesh is 60%-80% when the hexagonal prism-shaped grinding media is used to grind the galena particles.

[0023] Among them, such as Figure 2 As shown, the hexagonal prism-shaped grinding media is made of the same cast iron material as conventional cast balls, with a length-to-height ratio of 1 / 3.

[0024] like Figure 1As shown, the verification method for improving the flotation recovery rate of galena under this grinding system includes the following steps: (1) Select appropriate hexagonal prism and spherical grinding media according to the size of the galena particles being ground, and select the required grinding environment according to the test requirements; (2) Weigh 10 portions of 500g ore samples, with a grinding concentration of 75%, i.e., add 167ml of water, and grind for 2, 4, 6, 8 and 10 minutes respectively using hexagonal prism-shaped and spherical grinding media in a mill. The ground ore products were then sieved, and the -200 mesh yield corresponding to different grinding times for the two types of media was calculated. The grinding curves for hexagonal prism-shaped and spherical grinding media are shown in the figure below. Figure 3 and Figure 4 ; (3) Based on the grinding time as the X-axis and the -200 mesh yield corresponding to different grinding times as the Y-axis, draw and simulate the relationship between grinding time and -200 mesh yield under two different shaped media. (4) Based on the relationship diagram, find the grinding times corresponding to 60%, 65%, 70%, 75%, and 80% of the -200 mesh yield in the grinding curves of the two grinding media systems, i.e., t. 六60% t 六65% t 六70% t 六75% t 六80% The times were 6.33 min, 6.68 min, 7.03 min, 7.34 min, and 7.67 min, respectively. 球60% t 球65% t 球70% t 球75% t 球80% The times were 5.59 min, 5.98 min, 6.38 min, 6.75 min, and 7.11 min, respectively. (5) Weigh out several 500g samples of raw galena ore and grind them separately using hexagonal prism-shaped grinding media. 六60% t 六65% t 六70% t 六75% t 六80% And grinding with spherical grinding media respectively 其它60% t 其它65% t 其它70% t 其它75% t 其它80% The resulting ore was ground. (6) The ores after different grinding processes are transferred to flotation cells for flotation. The reagent system is kept consistent throughout the flotation process. The flotation process is as follows: Figure 5As shown, each flotation process adopts a roughing, cleaning, and scavenging process. During the roughing process, 2000g / t of lime, 80g / t of butylammonium black powder, and 100g / t of T16 are added; during the cleaning process, 1000g / t of lime and 50g / t of T16 are added; and during the scavenging process, 40g / t of butylammonium black powder is added.

[0025] Calculate the flotation recovery rate of galena separately: After flotation, the mass of the flotation concentrate was weighed, and the grades of the flotation tailings and flotation concentrate were analyzed, as shown in Table 1 and Table 2.

[0026] Table 1 Relevant flotation parameters of hexagonal prism-shaped abrasive media

[0027] Table 2 Relevant Flotation Indicators for Spherical Grinding Media

[0028] The grade of Pb in each batch of flotation ore is accurately derived, and the grade of Pb in the ore is calculated using the formula: (1); in, This represents the Pb grade in the raw ore. The grade of Pb in the concentrate. The grade of Pb in the tailings. For the yield of concentrate, The yield of tailings; For example, when the -200 mesh content is 80%, the Pb grade in the raw ore treated by hexagonal prism and spherical grinding media is [value missing].

[0029]

[0030] The ore grades from all groups of tests are summarized in Table 3.

[0031] Table 3. Pb grade of raw ore in all groups of tests

[0032] Calculate the recovery rate for each group of galena flotation: (2) in, The recovery rates of lead ore flotation at different yields below -200 mesh were calculated. i Different yields for -200 mesh.

[0033] The results showed that, under the same grinding results, i.e. the same grinding fineness, the hexagonal prism grinding media achieved the highest flotation recovery and the best flotation effect. For example, when the -200 mesh content is 80%, the recovery rate of concentrate obtained from hexagonal prism and spherical grinding media is...

[0034]

[0035] The concentrate recovery results from all groups of experiments are summarized in Table 4.

[0036] Table 4. Pb recovery rate in concentrate for all test groups

[0037] The flotation recovery rates of galena ground by the two grinding media are compared, as shown in Table 5.

[0038] Table 5. Differences in flotation parameters after using two different grinding media

[0039] As shown in Table 5, under the same grinding fineness, i.e. the same proportion of -200 mesh, the recovery rate of galena after grinding with hexagonal prism grinding media is higher, which is about 3% higher than that of grinding with the same spherical grinding media. Moreover, the improvement rate increases as the grinding fineness decreases.

[0040] Comparative Example 1 The biggest difference between this comparative example and Example 1 is that a short-head truncated cone mill was used as the grinding medium. A 500g ore sample was ground using a ball mill to achieve a grinding concentration of 75%, grinding to -200 mesh with a yield of 80%. The sample was then transferred to a flotation cell for flotation. The reagent regimen remained consistent throughout the flotation process, and the flotation flow was as follows: Figure 5 As shown, each flotation process employs a roughing, cleaning, and scavenging process. During roughing, 2000 g / t of lime, 80 g / t of butylammonium black reagent, and 100 g / t of T16 are added; during cleaning, 1000 g / t of lime and 50 g / t of T16 are added; and during scavenging, 40 g / t of butylammonium black reagent is added. Compared to the 93.72% recovery rate of lead ore under hexagonal prism grinding media in Table 4, the recovery rate of galena flotation under short-headed truncated cone grinding media is lower, only roughly the same as that under spherical grinding media. This demonstrates that other shapes of grinding media used in ball mills cannot achieve the effect of this invention in improving the recovery rate of galena flotation.

[0041] Comparative Example 2 The biggest difference between this comparative example and Example 1 is that hexagonal prism and spherical grinding media were used to grind galena particles to a density of -200 mesh with a yield of 50%, and the particles were then transferred to a flotation cell for flotation. The reagent formulation remained consistent throughout the flotation process, and the flotation procedure was as follows: Figure 5As shown, each flotation process employs a roughing, cleaning, and scavenging procedure. During the roughing process, 2000 g / t of lime, 80 g / t of butylammonium black reagent, and 100 g / t of T16 are added; during the cleaning process, 1000 g / t of lime and 50 g / t of T16 are added; and during the scavenging process, 40 g / t of butylammonium black reagent is added. It was found that when hexagonal prism-shaped and spherical grinding media were used to grind galena particles to -200 mesh with a yield of 50%, the flotation recoveries were 90.88% and 85.32%, respectively. This demonstrates that spherical grinding media, used in ball mills, cannot achieve the improved galena flotation recovery effect of this invention at lower galena grinding fineness.

[0042] The specific embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for improving the flotation recovery rate of galena in a grinding system, characterized in that: Using hexagonal prism-shaped grinding media instead of traditional spherical media to grind galena particles will improve the flotation recovery rate of galena while achieving the same grinding results.

2. The method for improving the flotation recovery rate of galena in the grinding system according to claim 1, characterized in that: The hexagonal prism-shaped grinding media grinds galena particles down to 200 mesh with a yield of 60%-80%.

3. The method for improving the flotation recovery rate of galena in the grinding system according to claim 1, characterized in that: The hexagonal prism-shaped grinding media is made of cast iron, the same material as conventional cast balls, with a length-to-height ratio of 1 / 3.

4. A verification method for improving the flotation recovery rate of galena under the grinding system according to claim 1, characterized in that the steps are as follows: include: (1) Select appropriate size hexagonal prism or other shapes of grinding media according to the size of the galena particles being ground, and select the required grinding environment according to the test requirements; (2) Weigh several galena ore samples and grind them in a mill with hexagonal prism and other grinding media for 2 min, 4 min, 6 min, 8 min and 10 min respectively. Then, screen the discharged ore after grinding and calculate the -200 mesh yield corresponding to the two types of media at different grinding times. (3) Based on the grinding time as the x-axis and the -200 mesh yield corresponding to different grinding times as the y-axis, draw and simulate the relationship between grinding time and -200 mesh yield under two different shaped media. (4) Based on the relationship diagram, select the grinding time corresponding to the -200 mesh yield of 60%, 65%, 70%, 75%, and 80%, respectively, which is t. 其它60% t 其它65% t 其它70% t 其它75% t 其它80% , and t 六60% t 六65% t 六70% t 六75% t 六80% ; (5) Weigh out several portions of raw galena ore samples and grind them separately using hexagonal prism-shaped grinding media. 六60% t 六65% t 六70% t 六75% t 六80% And grinding with other shapes of grinding media respectively. 其它60% t 其它65% t 其它70% t 其它75% t 其它80% Grind the ore; (6) Different ground ores were transferred to flotation cells for flotation. The reagent system was kept consistent during the flotation process. The flotation recovery rate of galena was calculated separately. It was verified that under the same crushing result, that is, the same grinding fineness, the flotation recovery rate obtained by using hexagonal prism grinding media was the highest and the flotation effect was the best.

5. The verification method for improving the flotation recovery rate of galena under the grinding system according to claim 4, characterized in that: The calculated recovery rate of galena flotation is: After flotation, the mass of the flotation concentrate was weighed, and the grades of the flotation tailings and flotation concentrate were analyzed separately to accurately derive the Pb grade in each batch of raw ore. The Pb grade in the raw ore was then calculated using the formula: （1）； in, This represents the Pb grade in the raw ore. The grade of Pb in the concentrate. The grade of Pb in the tailings. For the yield of concentrate, The yield of tailings; Calculate the recovery rate for each group of galena flotation: （2） in, The recovery rates of lead ore flotation at different yields below -200 mesh were calculated. i Different yields for -200 mesh.

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