A method for comprehensive utilization of reduced porphyry copper ore resources

Abstract

The present invention discloses a method for comprehensive utilization of reduced - quantity resources of porphyry copper deposits, which comprises the following steps: S1: semi - autogenous grinding circuit operation; S2: primary precise classification; S3: secondary precise classification; S4: roughing flotation of medium and coarse particles in fine screening. The present invention adopts a mill combination of semi - autogenous grinding + pebble crusher + rod mill, which can grind the ore relatively evenly and finely, ensure that copper minerals before entering the subsequent grinding and flotation system are not easily over - ground, and improve the copper recovery effect. By using the mineral composition characteristics of porphyry copper deposits to determine the precise screening of fine - grained grades, it not only provides a significant guarantee for obtaining good technical and economic indexes in subsequent grinding operations, but also meets the requirements of the gradation of manufactured sand on the other hand.

Description

Technical Field

[0001] The present invention relates to the technical field of beneficiation of low-grade copper minerals, and particularly relates to a method for comprehensive utilization of reduced resources of porphyry copper deposits. Background Art

[0002] Porphyry copper deposits are the world's most important copper deposits, accounting for half of the world's proven copper ore reserves, and are also one of the most important copper deposit types in China. However, the copper grade of porphyry copper deposits is relatively low, and with the continuous increase in the demand for copper ore resources in China, high-grade porphyry copper deposits are facing an increasingly depleted situation. Currently, the average copper grade is only about 0.4%, and there are still a large number of low-grade copper ores with a grade of 0.2% - 0.25%. In actual production applications, there is a trend that the lower the copper grade of the raw ore, the lower the copper recovery rate index. At the same time, due to the too low copper grade of the raw ore, it will also affect the compliance of the copper grade in the copper concentrate product, and it is difficult to recover and utilize under the condition that the energy consumption and material consumption of the ball milling operation remain unchanged, resulting in a large amount of waste of resources. At the same time, with the increase in the mining dilution rate, the generation of more tailings further restricts the development of copper mining enterprises and also poses a great test to the service life of the tailings pond.

[0003] Regarding how to improve the feed grade of low-grade ore entering the beneficiation system, domestic and foreign researchers have carried out a large amount of research work in the field of intelligent optoelectronic beneficiation technology. Among them, image color sorting technology and XRT (transmission technology) are relatively mature in application, and they sort ores through the differences in the surface characteristics or internal characteristic information of the ores. Currently, it is commonly used for the sorting of ores such as lead, zinc, and wolframite. The veins of such deposits are usually banded, the vein is relatively narrow, the ore types are either dense or stockwork, and the surrounding rock is significantly mixed and depleted during the mining process, and the boundary between waste rock and ore is clear, which is more suitable for waste rejection. In addition, some types of copper deposits also match this characteristic, such as skarn-type copper deposits. For porphyry copper deposits, their deposits often have certain alteration and mineralization zoning, the ores are distributed in a fine vein-disseminated form, the ore bodies are large, and the amount of surrounding rock mixed in during the mining process is small, further resulting in a small difference in the boundary between copper ore and gangue and poor adaptability for waste rejection.

[0004] In addition, the copper minerals in porphyry copper deposits are mainly chalcopyrite, with a hardness of 3 - 4, and the gangue minerals are mainly quartz and feldspar. Among them, the hardness of feldspar minerals is 6 - 6.5, and the hardness of quartz is 7.0, which is more difficult to grind than chalcopyrite. Currently, the commonly used grinding process flow in newly built copper concentrators is "SABC" (semi-autogenous grinding + ball milling + pebble crushing), which will grind some of the easily ground chalcopyrite in porphyry copper deposits to a particle size of -0.01mm, resulting in over-grinding and being difficult to effectively recover. In addition, some chalcopyrite is intergrown with the difficult-to-grind feldspar and quartz gangue, and this part of the combined ore is difficult to grind fine, resulting in that some chalcopyrite embedded in the coarse-grained ore is also difficult to recover, causing the loss of copper metal.

[0005] Chinese Patent Application No. CN202211063076X discloses a method for pre-selection of gold ore to discard waste and reduce over-grinding. The method first screens and classifies the hydrocyclone underflow in the gold ore grinding and classification closed-circuit system to obtain coarse-grained minerals, medium-grained minerals, and fine-grained minerals. Then, the coarse-grained minerals are returned to the ball mill for re-grinding, and the medium-grained minerals enter the heavy medium separation system. The tailings from the heavy medium separation are treated as waste rock, and the concentrate from the heavy medium separation is returned to the ball mill for re-grinding. Finally, the fine-grained minerals are subjected to flash flotation to obtain high-grade gold concentrate as the product, and the flotation tailings are returned to the ball mill for re-grinding. The inventive method mainly aims to achieve efficient separation between the main useful minerals and gangue minerals in gold mines, reduce the amount of ore entering the flotation process, and pre-flotate the useful minerals that are monomer-dissociated in the grinding and classification closed-circuit, avoiding the continuous circulation and accumulation of these minerals due to their large specific gravity during hydrocyclone classification, which may cause over-grinding and affect the gold recovery rate.

[0006] Chinese Patent Application No. CN202110958593.2 discloses a method for pre-selection of non-ferrous metal ore to discard waste. The method first obtains a first coarse ore, a first fine ore, and a first qualified ore through crushing and the first screening and classification. The first coarse ore is pre-selected and discarded through an intelligent ore sorting device to remove the gangue tailings therein. The remaining first rough concentrate is crushed and then subjected to the second screening and classification to obtain a second fine ore and a second qualified ore. Finally, the first fine ore and the second fine ore are pre-selected and discarded through heavy medium beneficiation to further remove the gangue tailings therein. The concentrate obtained from the heavy medium beneficiation is the qualified ore. In addition, the intelligent ore sorting device can also be used alone for waste discarding. Therefore, the core of this invention is the intelligent ore sorting device. As can be seen from the embodiments of this invention, it has good effects when applied to wolframite and lead-zinc ore respectively, but has poor effects on copper ores distributed in fine vein-disseminated form, especially porphyry copper ores. Summary of the Invention

[0007] One technical problem solved by the present invention is to provide a method for comprehensive utilization of reduced resources of porphyry copper ore, aiming at the problem of comprehensive utilization of reduced resources of porphyry copper ore, reducing energy consumption and cost, significantly reducing the output of flotation tailings, and effectively improving production capacity.

[0008] The technical solution adopted by the present invention is as follows: A method for comprehensive utilization of reduced resources of porphyry copper ore, comprising the following steps: S1: Semi-autogenous grinding cycle operation. After the low-grade porphyry copper ore is ground by semi-autogenous grinding, the discharged ore enters the coarse screening operation to obtain coarse-screened coarse particles and coarse-screened fine particles respectively. Among them, the coarse-screened coarse particles are returned to the semi-autogenous grinding after being crushed and ground by the pebble crusher to form a closed loop, and the coarse-screened fine particles enter S2;

[0009] S2: Primary precise classification. The coarsely screened fine particles obtained in S1 enter the high-frequency vibrating screen for primary precise classification to obtain primary refined coarse particles, primary refined medium particles, and primary refined fine particles respectively. Among them, the primary refined coarse particles enter S3, the primary refined medium particles enter S4, and the primary refined fine particles enter the grinding and flotation system. S3: Secondary precise classification. The primary refined coarse particles obtained in S2 enter the grinding mill to be ground finely and then enter the high-frequency vibrating screen for secondary precise classification to obtain secondary refined coarse particles, secondary refined medium particles, and secondary refined fine particles respectively. Among them, the secondary refined coarse particles are returned to the grinding mill to form a closed circuit. The secondary refined medium particles and the primary refined medium particles obtained in S2 are combined and enter S4, and the secondary refined fine particles and the primary refined fine particles obtained in S2 are combined and enter the grinding and flotation system. S4: Coarse particle flotation of refined medium particles. The refined medium particles obtained in S2 and S3 are combined and enter the coarse particle flotation operation. After stirring, a combined collector is added. After two rough selection operations, copper rough concentrate and copper tailings of coarse particle flotation are obtained respectively. Among them, the copper rough concentrate of coarse particle flotation enters the grinding system, and the copper tailings of coarse particle flotation can be sold as building materials products such as machine-made sand.

[0010] As a further improvement of the present invention, in S1 and S2, the particle size screening range is +0.4mm, 0.4mm - 0.15mm, +0.15mm. By studying the mineral composition characteristics of porphyry copper ore, that is, there are differences in grindability between copper minerals and gangue minerals, and the particle size distribution characteristics of porphyry copper ore, that is, the dissemination size of chalcopyrite is relatively fine, the copper grade is relatively high in the -0.15mm particle size range, and the minimum particle size of the machine-made sand gradation product is 0.15mm, it is determined that the precise screening fine particle size is -0.15mm. On the one hand, this greatly improves the copper grade in the -0.15mm particle size ore, providing a major guarantee for obtaining good technical and economic indicators in the subsequent grinding operation. On the other hand, the +0.15mm particle size can also meet the requirements of machine-made sand gradation. If the particle size range entering the subsequent grinding and flotation operation is increased, not only will the copper grade of the flotation feed be reduced, but also the grinding time required for the copper particles to reach the specified fineness will be longer, and the ball mill power consumption will also be more. According to the requirements of the particle size range of the coarse particle flotation feed and combined with the comprehensive analysis of grinding energy consumption, it is determined that the precise screening medium particle size is 0.15mm - 0.4mm.

[0011] As a further improvement of the present invention, in S3, the grinding mill is a rod mill. Adopting a mill combination of semi-autogenous grinding + pebble crushing + rod mill can grind the ore relatively evenly, ensure that the copper minerals before entering the subsequent grinding and flotation system are not prone to over-grinding, and improve the copper recovery effect.

[0012] As a further improvement of the present invention, in the step S4, the combined collector for coarse particle flotation is butyl xanthate and glycerol monolaurate sulfate. The dosage of butyl xanthate in the first roughing operation is 150 - 200 g / t, and that of glycerol monolaurate sulfate is 30 - 40 g / t. The dosage of butyl xanthate in the second roughing operation is 50 - 100 g / t, and that of glycerol monolaurate sulfate is 10 - 20 g / t. According to the requirements of the feed particle size range for coarse particle flotation and the comprehensive analysis of grinding energy consumption, the accurate screening medium particle size is determined to be 0.15 mm - 0.4 mm. Further considering that the on-site actual production application is relatively extensive, that is, in the classification operation, some gangue fines are not screened out in time from the -0.15 mm particle size and instead are screened out from the 0.15 mm - 0.4 mm particle size. If this part of the fines is mixed into the manufactured sand, it will cause the mud content of the final manufactured sand product to exceed the standard, which is reflected in a high methylene blue value. At the same time, too high sulfur content in the manufactured sand will also affect its quality and economic value. Therefore, in the coarse particle flotation, the fines entering the 0.15 mm - 0.4 mm particle size are utilized, and the combined collector butyl xanthate and glycerol monolaurate sulfate are added. This combined collector can replace the addition of water-soluble foaming agents, increase the foam viscosity, and promote the floating of slime. At the same time, using this part of the slime, under the synergistic effect of the combined collector, it further entrains copper-sulfur minerals to float together. In particular, it can effectively recover the fine-grained copper-sulfur minerals that are difficult to obtain. This measure can reduce the sulfur content of the manufactured sand while also making the copper content in the tailings after the coarse particle flotation operation of this particle size less than 0.1%, and the loss of copper metal is relatively small.

[0013] As a further improvement of the present invention, in the step S4, compared with the traditional flotation machine, the flotation machine used for coarse particle flotation has a shallower cell depth and a relatively larger air inflow.

[0014] The beneficial effects of the present invention are as follows:

[0015] 1. The present invention adopts a mill combination of semi-autogenous grinding + pebble crushing + rod mill, which can grind the ore relatively evenly, ensure that the copper minerals before entering the subsequent grinding and flotation system are not easily over-ground, and improve the copper recovery effect.

[0016] 2. Utilizing the mineral composition characteristics of porphyry copper ore, there are differences in grindability between copper minerals and gangue minerals, as well as the particle size distribution characteristics of porphyry copper ore minerals, the accurate screening fine particle size is determined to be -0.15 mm. On the one hand, it greatly improves the copper grade in the -0.15 mm particle size ore, providing a major guarantee for obtaining good technical and economic indicators in the subsequent grinding operation. On the other hand, the +0.15 mm particle size can also meet the requirements of the manufactured sand gradation.

[0017] 3. According to the requirements of the coarse flotation feed size range, combined with the comprehensive analysis of grinding energy consumption, the size of the precise screening is determined to be 0.15mm-0.4mm. At the same time, it is further considered that the actual production application on site is relatively extensive, that is, in the grading operation, some gangue fine mud will not be screened out from the -0.15mm particle size in time, but will be screened out from the 0.15mm-0.4mm particle size. If this part of fine mud is mixed into the machine-made sand, the mud content of the final machine-made sand product will exceed the standard, which is reflected in the high methylene blue value; at the same time, the excessive sulfur content in the machine-made sand will also affect its quality and economic value. Therefore, in the coarse-grained flotation, the fine mud with a particle size of 0.15mm-0.4mm is used, and the combined collectors of butyl xanthate and glycerol monolaurate sulfate are added to replace the addition of water-soluble frothers, increase the foam viscosity, and promote the floating of the ore mud; at the same time, this part of the ore mud is used, under the synergistic effect of the combined collector, to further float the copper-sulfur minerals together; in particular, it can effectively recover the difficult-to-obtain fine-grained copper-sulfur minerals. This move can reduce the sulfur content of the machine-made sand, and can also make the copper content of the tailings of this particle size after the coarse-grained flotation operation reach less than 0.1%, and the loss of copper metal is relatively small.

[0018] 4. At the same time, the copper coarse concentrate after coarse particle flotation enters the subsequent grinding and flotation system, which can further improve the grade of the grinding and flotation system. Under the condition of the same semi-autogenous grinding processing capacity, it significantly reduces the processing capacity of subsequent grinding and flotation operations, reduces the energy consumption and material consumption costs of the grinding and flotation operation process, effectively improves production capacity, and significantly reduces the output of flotation tailings, providing great support for increasing the service life of the tailings pond. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the present invention.

[0020] Figure 2 This is the existing process flow chart. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] As shown in the figure, a method for comprehensive utilization of porphyry copper ore reduction resources includes the following steps:

[0023] S1: Semi-autogenous grinding cycle operation. After the porphyry low-grade copper ore is semi-autogenous ground, the ore is discharged into the coarse screening operation to obtain coarse particles and fine particles. The coarse particles are crushed and ground by stone and then returned to the semi-autogenous grinding to form a closed loop. The fine particles enter S2.

[0024] S2: Primary precise classification. The coarse-screened fine particles obtained in S1 enter the high-frequency vibrating screen for primary precise classification, respectively obtaining primary fine-screened coarse particles, primary fine-screened medium particles, and primary fine-screened fine particles. Among them, the primary fine-screened coarse particles enter S3, the primary fine-screened medium particles enter S4, and the primary fine-screened fine particles enter the grinding and flotation system.

[0025] S3: Secondary precise classification. The primary fine-screened coarse particles obtained in S2 enter the grinding mill to be ground fine, and then enter the high-frequency vibrating screen for secondary precise classification, respectively obtaining secondary fine-screened coarse particles, secondary fine-screened medium particles, and secondary fine-screened fine particles. Among them, the secondary fine-screened coarse particles are returned to the grinding mill to form a closed circuit. The secondary fine-screened medium particles and the primary fine-screened medium particles obtained in S2 are combined and enter S4. The secondary fine-screened fine particles and the primary fine-screened fine particles obtained in S2 are combined and enter the grinding and flotation system.

[0026] S4: Coarse particle flotation of fine-screened medium particles. The fine-screened medium particles obtained in S2 and S3 are combined and enter the coarse particle flotation operation. After stirring, a combined collector is added. After two rough selection operations, respectively obtain copper rough concentrate of coarse particle flotation and copper tailings of coarse particle flotation. Among them, the copper rough concentrate of coarse particle flotation enters the grinding system, and the copper tailings of coarse particle flotation can be sold as building materials products such as machine-made sand.

[0027] Furthermore, by studying the grindability difference between copper minerals and gangue minerals in porphyry copper ore, as well as the particle size distribution characteristics of porphyry copper ore minerals, the particle size screening intervals in S1 and S2 are +0.4mm, 0.4mm - 0.15mm, +0.15mm.

[0028] Furthermore, to prevent over-grinding, ensure that the ore is ground fine relatively evenly, and improve the copper recovery effect, in S3, the grinding mill is a rod mill.

[0029] Furthermore, the on-site actual production application is relatively extensive. That is, in the classification operation, some gangue fines are not screened out in time from the -0.15mm particle size, but are instead screened out from the 0.15mm - 0.4mm particle size. If this part of the fines is mixed into the manufactured sand, it will cause the problem of a high methylene blue value in the final manufactured sand product. In S4, the combined collector for coarse-grained flotation is butyl xanthate and glycerol monolaurate sulfate. The dosage of butyl xanthate in the first roughing operation is 150 - 200g / t, and that of glycerol monolaurate sulfate is 30 - 40g / t. The butyl xanthate in the second roughing operation is 50 - 100g / t, and the dosage of glycerol monolaurate sulfate is 10 - 20g / t. In coarse-grained flotation, the fines with a particle size of 0.15mm - 0.4mm are utilized, and the combined collectors butyl xanthate and glycerol monolaurate sulfate are added. This combined collector can replace the addition of water-soluble foaming agents, increase the foam viscosity, and promote the floating of slime. At the same time, by utilizing the fines with a particle size of 0.15mm - 0.4mm, under the synergistic effect of the combined collector, it further entrains copper-sulfur minerals to float together, especially effectively recovering fine-grained copper-sulfur minerals that are difficult to obtain traditionally. This measure can reduce the sulfur content of the manufactured sand while also making the tailings after the coarse-grained flotation operation of this particle size contain less than 0.1% copper, with a relatively small loss of copper metal.

[0030] Furthermore, in S4, the flotation machine used in coarse-grained flotation has a shallower cell depth and a relatively larger air inflow compared to traditional flotation machines.

[0031] Example 1: A certain bornite mine in Anhui. The average copper grade of the raw ore is about 0.455%, among which the copper grade of the low-grade copper ore is about 0.246%. The copper minerals are mainly chalcopyrite, and the gangue minerals are mainly albite, oligoclase, and quartz.

[0032] After the porphyry-type low-grade copper ore is ground by semi-autogenous grinding, the discharged ore enters the coarse screening operation, and coarse-screened coarse particles and coarse-screened fine particles are obtained respectively. Among them, the coarse-screened coarse particles are returned to the semi-autogenous grinding after being crushed and ground by the pebble crusher to form a closed circuit. The coarse-screened fine particles enter the high-frequency vibrating screen for the first precise classification, and the first-precision-screened coarse particles, the first-precision-screened medium particles, and the first-precision-screened fine particles are obtained respectively. After the first-precision-screened coarse particles are ground fine by the rod mill, they enter the high-frequency vibrating screen for the second precise classification, and the second-precision-screened coarse particles, the second-precision-screened medium particles, and the second-precision-screened fine particles are obtained respectively. Among them, the second-precision-screened coarse particles are returned to the rod mill to form a closed circuit. The second-precision-screened medium particles and the first-precision-screened medium particles are combined and enter the coarse-grained flotation operation. The second-precision-screened fine particles and the first-precision-screened fine particles are combined and enter the grinding and flotation system; the precision-screened medium particles are combined and enter the coarse-grained flotation operation. Two roughing operations are adopted. Among them, 200 g / t of butyl xanthate and 30 g / t of glycerol monolaurate sulfate are added in the first roughing flotation operation, and 100 g / t of butyl xanthate and 15 g / t of glycerol monolaurate sulfate are added in the second roughing flotation operation. The coarse-grained flotation copper rougher concentrate and the coarse-grained flotation copper tailings are obtained respectively. Among them, the coarse-grained flotation copper rougher concentrate enters the grinding and flotation system, and the coarse-grained flotation copper tailings can be sold as building materials products such as machine-made sand. Because the particle size of the coarse-grained flotation tailings is relatively large, the dewatering operation is extremely convenient and is used in the actual on-site production. After semi-autogenous grinding + pebble crushing + rod mill grinding, the results of the copper particle size distribution law are shown in Table 1, the results of the open-circuit test of the coarse-grained flotation of the precision-screened medium particles are shown in Table 2, and after the precision-screened coarse particles are recycled, the comprehensive test results of the flotation feed of the closed-circuit process are shown in Table 3, and the flotation test results are shown in Table 4.

[0033] Table 1 Results of the copper particle size distribution law

[0034]

[0035]

[0036] It can be seen from the results of the copper particle size distribution law that the copper grade in the -0.15 mm particle size fraction is significantly increased, and the weighted copper grade reaches 0.437%, which is 0.191 percentage points higher than the original ore grade, and the effect is significant.

[0037] Table 2 Results of the open-circuit test of the coarse-grained flotation of the precision-screened medium particles

[0038] Product Name Operation Yield / % Cu Grade / % Cu Operation Recovery Rate / % Coarse Particle Flotation Copper Concentrate 3.36 2.61 51.05 Coarse Particle Flotation Copper Tailings 96.64 0.087 48.95 Total 100.00 0.172 100.00

[0039] It can be seen from the results of the exploratory test of the coarse-grained flotation of the precision-screened medium particles that a copper rougher concentrate with a copper grade of 2.61% can be obtained, and the copper content in the copper tailings is 0.087%, and the separation effect is significant.

[0040] Table 3 Comprehensive test results of the flotation feed of the closed-circuit process

[0041] Product Name Yield / % Cu Grade / % Cu Distribution Rate / % Precision Screening of Fine Particles 30.45 0.381 47.13 Coarse Particle Flotation Copper Concentrate 3.21 2.36 30.77 Σ Flotation Comprehensive Feed 33.66 0.570 77.90 Coarse Particle Flotation Copper Tailings 66.34 0.082 22.10 Total 100.00 0.246 100.00

[0042] After the coarse particles are accurately screened and circulated, the comprehensive test results of flotation feed in the closed-circuit process show that the copper grade of the comprehensive flotation feed can reach 0.570%, which is 0.224 percentage points higher than the lower-grade ore, and 0.115 percentage points higher than the average copper grade of the ore; at the same time, two-thirds of the coarse flotation copper tailings produced from the low-grade copper ore are obtained in advance, and the copper loss is relatively small. They can be sold as machine-made sand grading products, which greatly extends the use mission of the tailings pond while making full use of their economic value, and is conducive to the construction of green mines. At the same time, only one-third of the flotation feed produced enters the on-site grinding and flotation system, which greatly reduces the energy and material consumption generated by the ball milling operation, saving energy and reducing consumption for the enterprise.

[0043] The flotation comprehensive feed is then fed into the on-site grinding and flotation system for separation. The flotation test results are shown in Table 4.

[0044] Table 4 Example flotation test results

[0045] Product Name Yield / % Cu Grade / % Cu Recovery Rate / % Flotation Copper Concentrate 2.42 21.85 92.81 Copper Tailings from Copper Separation 97.58 0.042 7.19 Total 100.00 0.570 100.00

[0046] From the flotation test results of the embodiment, it can be seen that after the flotation of the low-grade bornite pre-enriched by the method of the present invention, a copper concentrate with a copper grade of 21.85% and a copper recovery rate of 92.81% can be obtained. In summary, for a concentrator with a daily processing capacity of 10,000 tons, 17.79 tons of copper metal can be obtained every day. Calculated at an 85% pricing coefficient and a unit price of 65,000 yuan / ton, an economic benefit of 982,700 yuan of copper concentrate can be obtained every day; at the same time, 6,700 tons of machine-made sand can be obtained every day. Calculated at a 60% pricing coefficient and a unit price of 80 yuan / ton, an economic benefit of 321,600 yuan of machine-made sand can be obtained every day. Calculated at the actual operating days of the production mine of 330 days / year, a total of 430 million yuan of economic benefits can be obtained each year, with significant effects.

[0047] Comparative Example 1: Low-grade bornite ore that has not been treated by the method of the present invention is directly fed into an on-site flotation system. The flotation test results are shown in Table 5.

[0048] Table 5 Flotation test results of comparative example 1

[0049] Product Name Yield / % Cu Grade / % Cu Recovery Rate / % Flotation Copper Concentrate 1.10 18.85 84.32 Copper Tailings from Copper Separation 98.90 0.039 15.68 Total 100.00 0.246 100.00

[0050] From the flotation experiment results of Comparative Example 1, it can be seen that after the flotation of low-grade bornite without being treated by the method of the present invention, both the copper grade and copper recovery rate of the copper concentrate have significantly decreased. Similarly, for a concentrator with a daily processing capacity of 10,000 t, 20.74 t of copper concentrate can be obtained every day. Calculated at a pricing coefficient of 85% and a unit price of 65,000 yuan per ton, the economic benefit of copper concentrate of 1.146 million yuan can be obtained every day, and there is no economic benefit of manufactured sand. Calculated based on the actual operating days of the production mine of 330 days / year, the total economic benefit of 378 million yuan can be obtained every year. At the same time, the energy consumption of the ball milling operation of low-grade bornite without being treated by the method of the present invention is relatively higher, and the production operation cost of the enterprise is relatively large.

[0051] Comparative Example 2: Using well-known domestic intelligent ore sorting equipment, through X-ray technology and image recognition algorithms, there are successful implementation cases in mines such as skarn-type copper mines and lead-zinc mines, and key indicators such as sorting accuracy, belt speed, single-particle compatibility, and output have reached the international advanced level. Multi-gradient fine separation and waste rejection of low-grade bornite ore are carried out, and the test results are shown in Table 6.

[0052] Table 6 Multi-echelon test results of intelligent sorting equipment

[0053] Product Name Weight / kg Yield / % Copper Grade / % Copper Recovery Rate / % Waste Reject Tail 1 57.0 16.40 0.15 11.45 Waste Reject Tail 2 69.2 19.91 0.18 16.69 Waste Reject Tail 3 84.5 24.32 0.23 26.04 Waste Reject Copper Concentrate 136.8 39.37 0.25 45.82 Total 347.5 100.00 0.21 100.00

[0054] From the multi-echelon test results of the intelligent sorting equipment, it can be seen that the copper grade of the copper concentrate obtained after three times of waste rejection and fine separation operations is 0.25%, which is only 0.04 percentage points higher than that of the original low-grade copper ore, and the copper loss is serious, and the effect is not ideal.

[0055] In addition, the intelligent ore sorting equipment used in Comparative Example 2 of the present invention is not limited to this one. Waste rejection test studies have been carried out on the equipment of well-known domestic related manufacturers, and there is no obvious sorting effect. Combining the exploration test results of the equipment of each manufacturer, the main reason is that the copper ore grade is low, the density difference is small, and the imaging difference is small, resulting in an unsatisfactory sorting effect, which is also caused by the ore-forming characteristics of porphyry copper mines.

[0056] Those skilled in the art should be aware that the protection scheme of the present invention is not limited to the above embodiments, and various permutations, combinations and transformations can also be carried out on the basis of the above embodiments. Without departing from the spirit of the present invention, various transformations made to the present invention fall within the protection scope of the present invention.

Claims

1. A method for comprehensive utilization of reduced - quantity resources of porphyry copper deposits, comprising the following steps: S1: Semi-autogenous grinding circuit operation. After the porphyry-type low-grade copper ore is ground by semi-autogenous grinding, the discharge enters the coarse screening operation, and coarse-screened coarse particles and coarse-screened fine particles are obtained respectively. Among them, The coarse - screened coarse particles are returned to semi - autogenous grinding after being crushed and ground by pebble crushers to form a circulating closed - loop, and the coarse - screened fine particles enter S2; S2: Primary precise classification. The coarse - screened fine particles obtained in S1 enter a high - frequency vibrating screen for primary precise classification, and primary refined - screen coarse particles, primary refined - screen medium particles, and primary refined - screen fine particles are obtained respectively. Among them, the primary refined - screen coarse particles enter S3, the primary refined - screen medium particles enter S4, and the primary refined - screen fine particles enter the grinding and flotation system; S3: Secondary precise classification. The primary refined - screen coarse particles obtained in S2 are ground in a grinding mill and then subjected to secondary precise classification by a high - frequency vibrating screen, and secondary refined - screen coarse particles, secondary refined - screen medium particles, and secondary refined - screen fine particles are obtained respectively. Among them, the secondary refined - screen coarse particles are returned to the grinding mill to form a circulating closed - loop, the secondary refined - screen medium particles and the primary refined - screen medium particles obtained in S2 are combined and enter S4, and the secondary refined - screen fine particles and the primary refined - screen fine particles obtained in S2 are combined and enter the grinding and flotation system; S4: Coarse - particle flotation of refined - screen medium particles. The refined - screen medium particles obtained in S2 and S3 are combined and enter the coarse - particle flotation operation. After stirring, a combined collector is added. After two rough - selection operations, coarse - particle flotation copper rough concentrate and coarse - particle flotation copper tailings are obtained respectively. Among them, the coarse - particle flotation copper rough concentrate enters the grinding system, and the coarse - particle flotation copper tailings can be sold as building materials products such as machine - made sand.

2. The method for comprehensive utilization of reduced porphyry copper ore resources according to claim 1, characterized in that In S1 and S2, the particle - size screening ranges are +0.4 mm, 0.4 mm - 0.15 mm, and +0.15 mm.

3. The method for comprehensive utilization of reduced porphyry copper ore resources according to claim 1, characterized in that In S3, the grinding mill is a rod mill.

4. The method for comprehensive utilization of reduced porphyry copper ore resources according to claim 1 is characterized in that In S4, the combined collector for coarse - particle flotation is butyl xanthate and glycerol monolaurate sulfate, where For the first rough - selection operation, the dosage of butyl xanthate is 150 - 200 g / t, and the dosage of glycerol monolaurate sulfate is 30 - 40 g / t. For the second rough - selection operation, the dosage of butyl xanthate is 50 - 100 g / t, and the dosage of glycerol monolaurate sulfate is 10 - 20 g / t.

5. A method for comprehensive utilization of reduced porphyry copper ore resources according to claim 1, characterized in that In S4, compared with traditional flotation machines, the flotation machine used for coarse - particle flotation has a shallower cell depth and a relatively larger air - inflow rate.

Images