Method for improving recovery rate of reground and reseparated copper of pyrrhotite-containing copper ore copper middling

Abstract

The invention discloses a method for improving the recovery rate of reground and reseparated copper of pyrrhotite-containing copper ore copper middling. The method comprises the following steps: S1, crushing and grinding raw ore and mixing pulp; s2, primary roughing of ore pulp; s3, primary scavenging is conducted on roughing tailings in the S2; s4, primary concentration is conducted on the copper rough concentrate obtained in the step S2; s5, performing secondary scavenging on the tailings subjected to primary scavenging in the step S3; s6, the middlings 1 obtained in the S3 and the selected tailings obtained in the S4 are combined and then subjected to ore grinding again; s7, the middling ore pulp obtained in the step S6 is subjected to re-separation; s8, scavenging the separated crude tailings obtained in the step S7; s9, the separated rough concentrate obtained in the step S7 is finely selected; s10, the separated middlings obtained in the step S8 and the step S9 and the separated refined tailings are combined and returned to the step S7; s11, the tailings 1 obtained in the step S5 and the tailings 2 obtained in the step S8 are combined and then subjected to magnetic separation through a magnetic separator, and magnetic concentrate and total tailings are obtained; and S12, the magnetic concentrate obtained in the step S11 is subjected to size fraction grading, the magnetic concentrate with the size fraction ranging from 0.25 mm to 0.18 mm is obtained, and the process returns to the step S7. According to the method, the recovery effect of micro-fine particle copper is effectively improved through migration of coarse particles in the magnetic concentrate.

Description

Technical Field

[0001] The invention relates to the technical field of copper-sulfur mineral beneficiation engineering, and in particular to a method for improving the copper recovery rate of regrinding and re-selecting copper in copper ore containing pyrrhotite. Background Art

[0002] With the continuous development of technological iteration, my country's copper metal consumption has grown rapidly, and copper production has long ranked first in the world, which requires mining companies to increase the development of low-grade minerals. However, low-grade copper ore dressing is difficult and tailings are easily lost. In order to improve the copper recovery rate and reduce tailings losses, companies have continuously increased their investment in scientific research and developed a series of new processes and mineral processing agents, which effectively improved the recovery rate of rough copper.

[0003] In these new process flows, the copper middling regrinding and reselection process effectively reduces the middling circulation pressure of the conventional middling sequential return process and reduces the total tailings copper loss. The regrinding and reselection of copper middlings improves the total copper recovery rate to a certain extent, but over-grinding is inevitable, so the problem of high copper content in the regrinding tailings arises, that is, some fine-grained copper is difficult to recover. In response to the above problems, the present invention proposes a method for reducing the copper loss of the tailings of the regrinding and reselection of copper middlings containing pyrrhotite-type chalcopyrite ores. Therefore, the present application provides a method for improving the copper recovery rate of the regrinding and reselection of copper middlings of pyrrhotite-containing copper ores to meet the demand. Summary of the invention

[0004] The purpose of the present application is to provide a method for improving the copper recovery rate of regrinding and reselecting copper middlings of pyrrhotite-containing copper ore. By performing particle size classification on magnetic concentrates, a certain amount of coarse particles are obtained and returned to the regrinding middlings for merging and reselection, so that the content of coarse magnetic concentrate of this particle size in the ore pulp is increased. The introduced coarse magnetic concentrate itself is not easy to float, and acts as a "support body" and "stirring body" in the ore pulp system. The stirring effect increases the opportunities for fine chalcopyrite in the ore pulp to interact with reagents, and the supporting effect increases the opportunities for fine chalcopyrite in the ore pulp to adhere to bubbles, thereby increasing the floating amount of fine-grained chalcopyrite, thereby improving the copper recovery rate.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solution: a method for improving the copper recovery rate of regrinding and re-selecting copper from copper ore containing pyrrhotite, comprising the following steps; S1. The raw ore is crushed and ground to -0.074mm, accounting for 73%, and the slurry concentration is controlled at 38%; S2. The slurry is subjected to a roughing process to obtain a portion of copper concentrate and a portion of roughing tailings; S3. Perform a sweep on the rougher tailings in S2 to obtain a portion of medium ore 1 and a portion of swept tailings; S4. The copper rough concentrate obtained in S2 is subjected to a concentration to obtain a copper concentrate 1 and a concentrated tailings; S5. Perform secondary sweeping of the tailings obtained in S3 to obtain a portion of middlings 2 and a portion of tailings 1, and the middlings 2 are returned to S3; S6. The middling ore 1 obtained from S3 and the selected tailings obtained from S4 are combined and then ground again to -0.045mm, accounting for 82%; S7. reselecting the middling slurry obtained in S6 to obtain a separated coarse tailing and a separated coarse concentrate; S8. Sweep and select the separated coarse tailings obtained in S7 to obtain a separated middling and a tailings 2; S9. The separated coarse concentrate obtained in S7 is concentrated to obtain a copper concentrate 2 and a separated fine tailings; S10. Combine the separated middlings and separated tailings obtained in S8 and S9 and return to step S7; S11. The tailings 1 obtained from S5 and the tailings 2 obtained from S8 are combined and magnetically separated by a 3500Oe magnetic separator to obtain a magnetic concentrate and a total tailings; S12. The magnetic concentrate obtained in S11 is graded to obtain a magnetic concentrate with a particle size of 0.25 mm to 0.18 mm, and the magnetic concentrate is returned to S7.

[0006] As a preferred implementation in this example, in S2, the roughing collector is ester-200 and SN, with dosages of 20 g / t and 5 g / t respectively; the foaming agent is BC, with dosage of 10 g / t.

[0007] As a preferred implementation in this embodiment, in S3 and S4, the scavenging collectors are butyrate and SN, and the dosage is 5 g / t.

[0008] As a preferred implementation in this example, in S7, the separation roughing collector is ester-200, and the dosage is 10 g / t.

[0009] As a preferred implementation in this embodiment, in S8, the separation and scavenging collector is butyrate, and the dosage is 5 g / t.

[0010] As a preferred implementation in this embodiment, in S7 and S9, the separation equipment used is a flotation column.

[0011] As a preferred implementation in this embodiment, in S12, the grading equipment used is a high-frequency vibrating screen, the aperture of the upper screen is 0.25 mm, and the aperture of the lower screen is 0.18 mm.

[0012] As a preferred implementation in this embodiment, in S12, the particle size return amount is 21% of the total amount of the 0.25 mm to 0.18 mm particle size obtained by screening.

[0013] As a preferred implementation in this embodiment, in S12, the +0.25mm particle size and the -0.18mm particle size and the remaining -0.25mm+0.18mm are recombined to form a magnetic concentrate product.

[0014] In summary, the technical effects and advantages of the present invention are as follows: The invention has a reasonable structure. The invention selects a flotation column with a good recovery effect on fine particles as a coarse and fine equipment for regrinding the middlings, and cooperates with the "return" of coarse particles in the magnetic concentrate to effectively improve the recovery effect of fine copper particles. In the present invention, the coarse magnetic concentrate plays the main role of "supporting" and "stirring" in the ore pulp during regrinding. Compared with the flotation machine, the flotation column has a longer flotation time, and the action time of particles with reagents and bubbles is prolonged, while the fine copper particles are still prone to desorption. After the coarse particles are introduced into the ore pulp system, the coarse particles in the ore pulp system "support" the desorbed fine copper particles, increasing the probability of them reacting with reagents and bubbles again; the coarse particles "stir" the ore pulp system to cause irregular flow, thereby stirring the movement of the fine copper particles in the original ore pulp, thereby increasing the probability of them reacting with reagents and bubbles. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 It is a process flow chart of the present invention; Figure 2 This is a table of semi-industrial test results. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example: Figure 1 The method for improving the copper recovery rate of regrinding and re-selecting copper from copper ore containing pyrrhotite comprises the following steps: S1. The original ore is crushed and ground to -0.074mm, accounting for 73%. This particle size range is beneficial to the subsequent flotation process, because the appropriate particle size can increase the contact area between the ore particles and the flotation reagent, thereby improving the flotation efficiency. At the same time, this particle size range can also reduce the over-crushing phenomenon and avoid the generation of too much fine mud, which may affect the flotation effect. The slurry concentration is controlled to 38%. If the concentration is too high, the fluidity of the slurry in the flotation machine may deteriorate, affecting the flotation effect; if the concentration is too low, it may reduce the processing capacity of the flotation machine and increase energy consumption. The concentration of 38% can ensure that the slurry has good fluidity in the flotation machine, while ensuring that enough ore particles are in contact with the flotation reagent, thereby improving the copper recovery rate.

[0019] The concentration of 38% can ensure good fluidity of the pulp in the flotation machine, while ensuring that sufficient ore particles are in contact with the flotation reagent, thereby improving the recovery rate of copper; S2. The slurry is subjected to a roughing process to obtain a portion of copper concentrate and a portion of roughing tailings; S3. Perform a sweep on the rougher tailings in S2 to obtain a portion of medium ore 1 and a portion of swept tailings; S4. The copper rough concentrate obtained in S2 is subjected to a concentration to obtain a copper concentrate 1 and a concentrated tailings; S5. Perform secondary sweeping of the tailings obtained in S3 to obtain a portion of middlings 2 and a portion of tailings 1, and the middlings 2 are returned to S3; S6. The middling ore 1 obtained from S3 and the selected tailings obtained from S4 are combined and then ground again to -0.045mm, accounting for 82%; S7. reselecting the middling slurry obtained in S6 to obtain a separated coarse tailing and a separated coarse concentrate; S8. Sweep and select the separated coarse tailings obtained in S7 to obtain a separated middling and a tailings 2; S9. The separated coarse concentrate obtained in S7 is concentrated to obtain a copper concentrate 2 and a separated fine tailings; S10. Combine the separated middlings and separated tailings obtained in S8 and S9 and return to step S7; S11. The tailings 1 obtained from S5 and the tailings 2 obtained from S8 are combined and magnetically separated by a 3500Oe magnetic separator to obtain a magnetic concentrate and a total tailings; S12. The magnetic concentrate obtained in S11 is graded to obtain a magnetic concentrate with a particle size of 0.25 mm to 0.18 mm, and the magnetic concentrate is returned to S7.

[0020] The invention selects flotation columns with better recovery effect on fine particles as roughing and selecting equipment for regrinding middlings, and cooperates with the "return" of coarse particles in the magnetic concentrate to effectively improve the recovery efficiency of fine copper particles; the coarse magnetic concentrate mainly comes from tailings 1, and the magnetic concentrate obtained by magnetic separation of tailings 1 has a coarse particle size. After classification, it "returns" to the roughing flotation column of the regrinding middlings, thereby increasing the coarse particle content in the regrinding middling pulp. This part of the coarse particles will mainly act on the roughing process of the regrinding middlings. Due to the coarse particle size and difficulty in reacting with the reagent, after the reaction in the pulp is completed, it continues to enter the scavenging, and finally enters the tailings 2, merges with the tailings 1 and enters the magnetic separation again to complete the "return" effect; the coarse magnetic concentrate mainly plays the role of "support" and "stirring" in the regrinding middling pulp. Compared with the flotation machine, the flotation time of the flotation column is prolonged, and the action time of the particles with the reagent and the bubbles is prolonged, while the fine copper particles are still prone to desorption. After the coarse particles are introduced into the slurry system, the coarse particles support the desorbed fine-grained copper particles through the "supporting" effect in the slurry system, increasing the probability of them interacting with the reagent and bubbles again; the coarse particles cause irregular flow in the slurry system through the "stirring" effect, thereby stirring the movement of the fine-grained copper particles in the original slurry, thereby increasing the probability of them interacting with the reagent and bubbles.

[0021] As a preferred implementation in this example, in S2, the roughing collector is ester-200 and SN, with dosages of 20 g / t and 5 g / t respectively; the foaming agent is BC, with dosage of 10 g / t.

[0022] As a preferred implementation in this embodiment, in S3 and S4, the scavenging collectors are butyrrolidone and SN, and the dosage is 5 g / t.

[0023] As a preferred implementation in this example, in S7, the separation roughing collector is ester-200, and the dosage is 10 g / t.

[0024] As a preferred implementation in this embodiment, in S8, the separation and scavenging collector is butyrate, and the dosage is 5 g / t.

[0025] As a preferred implementation in this embodiment, in S7 and S9, the separation equipment used is a flotation column.

[0026] As a preferred implementation in this embodiment, in S12, the grading equipment used is a high-frequency vibrating screen, the aperture of the upper screen is 0.25 mm, and the aperture of the lower screen is 0.18 mm.

[0027] As a preferred implementation in this embodiment, in S12, the particle size return amount is 21% of the total amount of the 0.25 mm to 0.18 mm particle size obtained by screening.

[0028] During the production process of this ore, the 0.25mm+0.18mm particle size of magnetic concentrate accounts for 17%, and the 0.25mm+0.18mm particle size of "returning" accounts for 21% of its total amount. Calculated based on the original ore, the magnetic concentrate product accounts for 29% of the original ore content. The yield of coarse-grained magnetic concentrate from "returning" to the re-grinded intermediate ore is 1%, and the yield of intermediate ore is 8%, that is, the yield of "returning" intermediate ore is 9%. The yield of coarse particles of "returning" is the best. Small-scale tests have verified that the increase in the recovery rate of re-grinded copper concentrate when the yield of coarse-grained magnetic concentrate of "returning" is less than 1% or greater than 1% is less than 1%.

[0029] This embodiment is a semi-industrial test conducted at a copper ore dressing plant in Anhui. The dressing process of the dressing plant is the same as the schematic diagram of the invention. The re-grinded middlings are taken for semi-industrial testing, and the on-site magnetic concentrate is taken for small-scale high-frequency vibration screening and classification. The industrial hose pump takes the magnetic concentrate of the corresponding particle size according to the flow rate for "coarse particle vortex". The test was carried out to test whether the coarse particle magnetic concentrate "vortexes" and the amount of "vortexing". The semi-industrial test process is shown in the following table. The semi-industrial test results are shown in Figure 2 shown.

[0030] The semi-industrial test results in this embodiment show that the copper recovery rate of copper concentrate 2 can be significantly improved by "coarse grain return" of 21% -0.25mm + 0.18mm particle size magnetic concentrate, and the copper recovery rate is increased by 5.75 percentage points compared with the group without "coarse grain return". Increasing or decreasing the amount of "coarse grain return" is not as good as the effect of 21% return on the copper recovery rate of copper concentrate 2.

[0031] As a preferred implementation in this embodiment, in S12, the +0.25mm particle size and the -0.18mm particle size and the remaining -0.25mm+0.18mm are recombined to form a magnetic concentrate product.

[0032] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for improving the recovery rate of copper ore from regrinding and re-selecting copper in pyrrhotite-containing copper ore, characterized in that: The method comprises the following steps: S1. The raw ore is crushed and ground to -0.074mm, accounting for 73%, and the slurry concentration is controlled at 38%; S2. The slurry is subjected to a roughing process to obtain a portion of copper concentrate and a portion of roughing tailings; S3. Perform a sweep on the rougher tailings in S2 to obtain a portion of medium ore 1 and a portion of swept tailings; S4. The copper rough concentrate obtained in S2 is subjected to a concentration to obtain a portion of copper concentrate 1 and a portion of concentrated tailings; S5. Perform secondary sweeping of the tailings obtained in S3 to obtain a portion of middlings 2 and a portion of tailings 1, and the middlings 2 are returned to S3; S6. The middling ore 1 obtained from S3 and the selected tailings obtained from S4 are combined and then ground again to -0.045mm, accounting for 82%; S7. reselecting the middling slurry obtained in S6 to obtain a separated coarse tailing and a separated coarse concentrate; S8. Sweep and select the separated coarse tailings obtained in S7 to obtain a separated middling and a tailings 2; S9. The separated coarse concentrate obtained in S7 is concentrated to obtain a copper concentrate 2 and a separated fine tailings; S10. Combine the separated middlings and separated tailings obtained in S8 and S9 and return to step S7; S11. The tailings 1 obtained from S5 and the tailings 2 obtained from S8 are combined and magnetically separated by a 3500Oe magnetic separator to obtain a magnetic concentrate and a total tailings; S12. The magnetic concentrate obtained in S11 is graded to obtain a magnetic concentrate with a particle size of 0.25 mm to 0.18 mm, and the magnetic concentrate is returned to S7.

2. The method for improving the copper recovery rate of regrinding and reselecting copper in pyrrhotite-containing copper ore according to claim 1, characterized in that: In the S2, the roughing collector is ester-200 and SN, with the dosage being 20 g / t and 5 g / t respectively; the foaming agent is BC, with the dosage being 10 g / t.

3. The method for improving the copper recovery rate of regrinding and reselecting copper from pyrrhotite-containing copper ore according to claim 1, characterized in that: In S3 and S4, the scavenging collectors are butyrrolidone and SN, and the dosage is 5 g / t.

4. The method for improving the copper recovery rate of regrinding and reselecting copper in pyrrhotite-containing copper ore according to claim 1, characterized in that: In the S7, the separation roughing collector is ester-200, and the dosage is 10 g / t.

5. The method for improving the copper recovery rate of regrinding and reselecting copper in pyrrhotite-containing copper ore according to claim 1, characterized in that: In S8, the separation and scavenging collector is butyrrolidone, and the dosage is 5 g / t.

6. The method for improving the copper recovery rate of regrinding and reselecting copper from pyrrhotite-containing copper ore according to claim 1, characterized in that: In S7 and S9, the separation equipment used is a flotation column.

7. The method for improving the copper recovery rate of regrinding and reselecting copper from pyrrhotite-containing copper ore according to claim 5, characterized in that: In the S12, the grading device used is a high-frequency vibrating screen, the upper screen aperture is 0.25 mm, and the lower screen aperture is 0.18 mm.

8. The method for improving the copper recovery rate of regrinding and reselecting copper from pyrrhotite-containing copper ore according to claim 7, characterized in that: In S12, the particle size return amount is 21% of the total amount of the particle size of 0.25 mm to 0.18 mm obtained by screening.

9. The method for improving the copper recovery rate of regrinding and reselecting copper from pyrrhotite-containing copper ore according to claim 1, characterized in that: In S12, the +0.25 mm particle size, the -0.18 mm particle size and the remaining -0.25 mm + 0.18 mm are recombined to form a magnetic concentrate product.

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