Application of combined collecting agent in flotation of low-grade copper oxide ore

Abstract

The invention discloses application of a combined collecting agent in flotation of low-grade copper oxide ore, and belongs to the technical field of beneficiation flotation reagents. The combined collecting agent comprises a chelating agent and a xanthate collecting agent, the chelating agent is benzyl-N, N-dimethyl dithiocarbamic acid, the xanthate collecting agent is amyl xanthate, and the combined collecting agent is used for flotation of low-grade copper oxide ore. Ore is subjected to crushing, ore grinding, coarse separation and pulp mixing to obtain ore pulp to be floated, a gangue inhibitor is firstly added into the ore pulp, then sodium sulfide is added to activate copper oxide ore, and after activation, a combined collecting agent and a foaming agent are sequentially added to recover copper oxide minerals in the ore. Compared with a single xanthate collecting agent, the low-grade copper oxide ore combined collecting agent is small in agent dosage and convenient to add, the dosage of amyl xanthate serving as a collecting agent and the dosage of sodium sulfide serving as a vulcanizing agent are reduced, the beneficiation cost is reduced while the flotation recovery rate and grade of low-grade copper oxide ore are improved, and the low-grade copper oxide ore combined collecting agent is an environment-friendly agent.

Description

Technical Field

[0001] The invention relates to application of a combined collector in flotation of low-grade copper oxide ore, belonging to the technical field of ore dressing and flotation reagents. Background Art

[0002] Copper is a strategic metal resource. Copper and its alloys are widely used in mechanical metallurgy, energy petrochemicals, electronics and electrical, and national defense construction due to their excellent electrical conductivity, thermal conductivity, and wear resistance. At present, more than 80% of copper smelting raw materials are sulfide copper ore. With the increasing global demand for copper metal and the continuous exhaustion of high-quality copper ore resources, low-grade oxidized copper ore, as one of the important copper ore resources, is an important supplement to copper resources through its efficient recovery and utilization. China is the world's largest copper consumer. However, the current utilization rate of oxidized copper ore in my country is less than 10%, and the external dependence is relatively high. Many researchers have strengthened the research on the beneficiation and smelting technology of low-grade and difficult-to-select oxidized copper ore, and improved the utilization rate and recovery rate of resources, so as to improve the self-sufficiency rate of copper resources in my country.

[0003] Low-grade copper oxide ores have the characteristics of high oxidation rate, high binding rate, complex mineral composition and high content of floating gangue, which leads to low recovery rate. At present, the two commonly used beneficiation methods for low-grade copper oxide ores are chemical beneficiation and flotation. Chemical beneficiation processes include acid leaching, ammonia leaching, separation-flotation and bacterial leaching. Since the cost of chemical beneficiation is high and often cannot meet safety and environmental protection requirements, flotation methods with high recovery rate and large processing capacity, which can obtain high-grade concentrate at low cost, are currently the most important separation and recovery processes. Direct flotation is the earliest method used to treat copper oxide ores. The ore is not pre-sulfided with sodium sulfide, and is directly floated using higher fatty acids and their soaps, higher xanthates, thiols and chelating agents. However, this method has high reagent cost and poor flotation selectivity, and is only suitable for oxidized ores with simpler mineral composition. At present, the most commonly used and most widely used method for flotation of low-grade oxidized copper ore in industry is sulfide-xanthate flotation method. However, due to the large surface tension and defects of the cleavage surface of oxidized copper ore, its surface properties are unstable. Therefore, the sulfide film formed by the reaction of copper oxide and sulfiding agent is not uniform and stable. Usually, there are sulfide zones, semi-sulfide zones and non-sulfide zones on the surface of copper ore after sulfidation. Single collector xanthate is usually easy to adsorb in the sulfide zone, difficult to adsorb in the semi-sulfide zone and non-sulfide zone, and easy to fall off, which leads to the low flotation recovery rate of the sulfide-xanthate flotation process of traditional oxidized copper ore. For easy-floating oxidized copper ore, the recovery rate is only 60% to 70%, and the recovery rate of difficult-floating oxidized copper is even less than 50%.

[0004] In recent years, since many reagents are more efficient when used in combination than when used alone, more and more researchers have adopted combined collectors for flotation to capture low-grade oxidized copper ores. Combined collectors can be divided into two categories: homogeneous combined collectors and heterogeneous combined collectors, and their main mechanisms of action are co-adsorption, chelation and synergy. Xanthates, hydroxy acids and their combinations have strong affinity and selectivity for oxidized copper minerals, such as Z200, sodium hydroxamate and salicylic hydroxamic acid, among which Z200 has been used in industrial production due to its advantages of small dosage, high efficiency and green environmental protection. Therefore, the mechanism of action of the commonly used oxidized copper ore collectors mixed with other types of collectors in the direct flotation method is studied in depth, and new combined collectors are developed to expand the types and application range of collectors to meet the increasingly complex flotation recovery of low-grade copper ore resources. Summary of the invention

[0005] The present invention aims at the problems that the collector is difficult to stably adsorb, the flotation recovery rate is low, and the concentrate quality is poor in the sulfide-xanthate flotation method for low-grade oxidized copper ore, and provides an environmentally friendly oxidized copper ore flotation combined collector with small dosage and high recovery efficiency. The present invention first adds gangue inhibitor water glass and sodium hexametaphosphate, and then adds sodium sulfide to sulfide the low-grade oxidized copper mineral, which can change the surface properties of the mineral and the components of the ore pulp solution, and then adds the combined collector benzyl-N, N-dimethyldithiocarbamic acid and amyl xanthate, and promotes the hydrophobicity of the surface of the low-grade oxidized copper ore by exerting the synergistic effect of the two collectors, and finally adds the foaming agent pine oil to flotate and recover it.

[0006] The flotation process of the low-grade copper oxide ore of the present invention is one roughing, three sweeping and three refining. The qualified particle size pulp after crushing and separation is sent to the flotation machine, and then adjusted to a suitable pulp concentration. A gangue inhibitor is first added to inhibit gangue and disperse the ore mud, and then an activator sodium sulfide is added to pre-sulfide it, and then a combined collector is added to hydrophobicize it, and finally a frother is added to recover it.

[0007] The specific steps are as follows:

[0008] (1) Crushing and grinding: crushing and grinding the low-grade copper oxide ore to a particle size of -74 μm with a mass percentage of 70% to 80%. The ore pulp after grinding is screened using a 32-mesh vibrating screen;

[0009] (2) Roughing: transporting the qualified -32 mesh slurry in step (1) to an aerated flotation machine, adjusting the slurry to a slurry mass concentration of 20% to 40%, and sequentially adding a gangue inhibitor, an activator, a combined collector and a frother to the adjusted slurry to perform a primary roughing operation to obtain a primary roughing concentrate and a primary roughing tailings;

[0010] (3) scavenging: adding an activator, a combined collector and a frother to the primary roughing tailings of step (2) in sequence to carry out a primary scavenging operation to obtain a primary scavenging concentrate and a primary scavenging tailings; the primary scavenging concentrate is returned and incorporated into the primary roughing operation, and an activator, a combined collector and a frother are added to the primary scavenging tailings in sequence to carry out a secondary scavenging operation to obtain a secondary scavenging concentrate and a secondary scavenging tailings; the secondary scavenging concentrate is returned and incorporated into the primary scavenging operation, and an activator, a combined collector and a frother are added to the secondary scavenging tailings in sequence to carry out a tertiary scavenging operation to obtain a tertiary scavenging concentrate and a tertiary scavenging tailings; the tertiary scavenging concentrate is returned and incorporated into the secondary scavenging operation, and the tertiary scavenging tailings are copper oxide tailings;

[0011] (4) Concentration: adding a combined collector and a frother to the primary roughing concentrate of step (2) in sequence to carry out a primary concentration operation, thereby obtaining a primary concentrated concentrate and a primary concentrated tailings; the primary concentrated tailings are returned and incorporated into the primary roughing operation, and a combined collector and a frother are added to the primary concentrated concentrate in sequence to carry out a secondary concentration operation, thereby obtaining a secondary concentrated concentrate and a secondary concentrated tailings; the secondary concentrated tailings are returned and incorporated into the primary concentration operation, and the secondary concentrated concentrate is subjected to a third blank concentration operation, thereby obtaining a third concentrated concentrate and a third concentrated tailings; the third concentrated tailings are returned and incorporated into the second concentration operation, and the third concentrated concentrate is a copper oxide concentrate.

[0012] The copper grade of the low-grade oxidized copper ore in step (1) is 0.40% to 0.70%, and the main useful minerals include malachite and chrysocolla. The low-grade oxidized copper ore contains at least one or more gangue minerals of diopside, calcite, talc, quartz, clinochlore and mica.

[0013] In step (2), the gangue inhibitor is water glass and sodium hexametaphosphate, the activator is sodium sulfide, the combined collector is benzyl-N, N-dimethyldithiocarbamic acid and amyl xanthate, and the foaming agent is pine oil. The mass ratio of water glass and sodium hexametaphosphate added to the slurry is 3:1, and the mass ratio of benzyl-N, N-dimethyldithiocarbamic acid and amyl xanthate added to the slurry is (1-2):5. Among them, water glass and sodium hexametaphosphate not only play a role in inhibiting gangue and improving the concentrate enrichment ratio, but also can disperse the sludge in the slurry and reduce the impact of the sludge on the subsequent flotation process.

[0014] Step (2) is a primary roughing operation, in which the amount of inhibitor added is 1000-1600 g / t, the amount of activator added is 800-900 g / t, the amount of combined collector added is 250-500 g / t, and the amount of foaming agent added is 20-40 g / t.

[0015] In step (3), the activator is sodium sulfide, the combined collector is benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate, the foaming agent is pine oil, and the mass ratio of benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate added to the ore pulp is (1-2):5.

[0016] Step (3) is a three-stage scavenging operation. In step (3), the amount of reagents added to the primary roughing tailings is 300-400 g / t of activator, 150-300 g / t of combined collector, and 20-30 g / t of frother; the amount of reagents added to the primary scavenging tailings is 200-300 g / t of activator, 80-140 g / t of combined collector, and 20-30 g / t of frother; the amount of reagents added to the secondary scavenging tailings is 100-150 g / t of activator, 40-80 g / t of combined collector, and 10-20 g / t of frother.

[0017] In step (4), the activator is sodium sulfide, the combined collector is benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate, the foaming agent is pine oil, and the mass ratio of benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate added to the ore pulp is (1-2):5.

[0018] Step (4) is a three-stage concentration operation. In step (4), the amount of reagents added to the primary roughing concentrate is 50-120 g / t of combined collector and 20-30 g / t of frother; the amount of reagents added to the primary concentration concentrate is 30-60 g / t of combined collector and 10-20 g / t of frother.

[0019] The principle of the present invention is as follows:

[0020] In the synergistic system of the flotation process of low-grade copper oxide ore: the chelating agent benzyl-N,N-dimethyldithiocarbamic acid added first can chelate with the Cu component on the mineral surface through chelation, and the chelated product formed has stronger adsorption stability than the xanthate collector. At the same time, molecules with hydrophobic structures such as hydrocarbon groups and benzene rings cover the mineral surface, promoting further hydrophobicity of the mineral surface; when the hydrophobicity of the mineral surface is further enhanced, the bubbles start from the contact point with the copper oxide and expel most of the hydration film from the surface of the copper oxide ore particles, further promoting the interaction between the collector benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate and the mineral surface; as the chelating agent further acts on the Cu component on the mineral surface, the soluble Cu component on the mineral surface continues to decrease, thereby effectively reducing the Cu in the slurry. 2+ The concentration of amyl xanthate is reduced, and the mineralization effect of flotation foam is significantly enhanced, making the foam layer more stable.

[0021] Benzyl-N,N-dimethyldithiocarbamic acid may react with copper ions on the surface of minerals as follows:

[0022]

[0023] The reaction equation of benzyl-N,N-dimethyldithiocarbamic acid and copper ion

[0024] Beneficial effects of the present invention:

[0025] (1) Compared with a single xanthate collector, the combined collector of the present invention has a chelate product formed by the chelating agent benzyl-N,N-dimethyldithiocarbamic acid and the Cu component on the surface of the mineral, which has stronger adsorption stability than the xanthate collector, and effectively improves the flotation recovery rate of the oxidized copper ore.

[0026] (2) The chelating agent benzyl-N,N-dimethyldithiocarbamic acid in the combined agent of the present invention consumes a large amount of soluble Cu components on the surface of the mineral through chelation, thereby effectively reducing the Cu content in the slurry. 2+ The concentration of amyl xanthate is greatly reduced.

[0027] (3) The chelating agent in the combined agent of the present invention is an organic agent with strong applicability and significant economic, social and environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described in detail below in conjunction with specific embodiments. The embodiments are only used to specifically illustrate the present invention, but the protection scope of the present invention is not limited to the contents described.

[0030] In the following embodiments of the present invention, the gangue inhibitor is water glass and sodium hexametaphosphate, the activator is sodium sulfide, the foaming agent is pine oil, the combined collector includes benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate, and the mass ratio of water glass and sodium hexametaphosphate added to the slurry is 3:1.

[0031] Embodiment 1: This embodiment processes the low-grade copper oxide ore in a certain place in Xinjiang, in which: Cu grade is 0.42%, SiO2 grade is 56.85%, CaO grade is 14.72%, MgO grade is 7.82%, Fe grade is 3.45%; the main useful minerals are malachite and chrysocolla, and the main gangue minerals are quartz, diopside, calcite, and talc; the mass percentage of copper is 42.72% for free copper oxide, 24.76% for combined copper oxide, 28.35% for primary copper sulfide, and 4.17% for secondary copper sulfide.

[0032] In this embodiment, the low-grade copper oxide ore is first crushed and ground. After crushing, the copper oxide ore is recovered by flotation using a flotation test process of one roughing, three fines and three sweeps. In the flotation, a combination of reagents is used to synergistically capture the copper oxide ore. The mass ratio of benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate in the combined collector is 1:5. Benzyl-N,N-dimethyldithiocarbamic acid enhances the hydrophobicity of copper oxide minerals through chelation, and forms a synergistic adsorption system with the subsequently added xanthate, thereby achieving efficient recovery of copper oxide minerals. The experimental flow chart is shown in FIG. Figure 1 As shown, the specific steps are as follows:

[0033] (1) Crushing and grinding: The copper oxide ore is crushed and ground to a particle size of -74 μm, accounting for 70% by mass. The ore pulp after grinding is screened using a 32-mesh vibrating screen;

[0034] (2) Roughing: transport the -32 mesh qualified slurry in step (1) to an aerated flotation machine, adjust the slurry to a slurry mass concentration of 40%, and sequentially add 1600 g / t of gangue inhibitor, 900 g / t of activator, 500 g / t of combined collector, and 40 g / t of frother to the adjusted slurry to perform a roughing operation to obtain a roughing concentrate and a roughing tailing;

[0035] (3) Scavenging: 400 g / t of activator, 300 g / t of combined collector and 30 g / t of frother are sequentially added to the primary roughing tailings of step (2) to carry out a primary scavenging operation to obtain a primary scavenging concentrate and a primary scavenging tailings; the primary scavenging concentrate is returned and incorporated into the primary roughing operation to form a closed loop, 300 g / t of activator, 140 g / t of combined collector and 30 g / t of frother are sequentially added to the primary scavenging tailings to carry out a secondary scavenging operation to obtain a secondary scavenging concentrate and a secondary scavenging tailings; the secondary scavenging concentrate is returned and incorporated into the primary scavenging operation to form a closed loop, 150 g / t of activator, 80 g / t of combined collector and 20 g / t of frother are sequentially added to the secondary scavenging tailings to carry out a tertiary scavenging operation to obtain a tertiary scavenging concentrate and a tertiary scavenging tailings; the tertiary scavenging concentrate is returned and incorporated into the secondary scavenging operation to form a closed loop, and the tertiary scavenging tailings are the final tailings;

[0036] (4) Concentration: 120 g / t of combined collector and 30 g / t of frother were added to the primary roughing concentrate of step (2) to perform a primary concentration operation, and a primary concentrated concentrate and a primary concentrated tailing were obtained; the primary concentrated tailing was returned and incorporated into the primary roughing operation, and 60 g / t of combined collector and 20 g / t of frother were added to the primary concentrated concentrate to perform a secondary concentration operation, and a secondary concentrated concentrate and a secondary concentrated tailing were obtained; the secondary concentrated tailing was returned and incorporated into the primary concentration operation, and the secondary concentrated concentrate was subjected to a third blank concentration operation to obtain a third concentrated concentrate and a third concentrated tailing; the third concentrated tailing was returned and incorporated into the second concentration operation, and the third concentrated concentrate was a copper oxide concentrate. The test results of this embodiment are shown in Table 1.

[0037] Comparative Example 1: The low-grade copper oxide ore treated in this example is consistent with that in Example 1, and the treatment process is consistent with that in Example 1, except that the collector is amyl xanthate. The test results of this comparative example are shown in Table 2.

[0038] Embodiment 2: This embodiment processes the low-grade copper oxide ore in a certain place of Yunnan, in which: Cu grade is 0.58%, SiO2 grade is 60.25%, CaO grade is 12.79%, MgO grade is 5.93%, Fe grade is 3.27%; the main useful minerals are malachite and chrysocolla, and the main gangue minerals are quartz, talc, diopside, calcite, and mica; the mass percentage of copper is 42.62% of free copper oxide, 24.78% of combined copper oxide, 27.85% of primary copper sulfide, and 4.75% of secondary copper sulfide.

[0039] In this embodiment, low-grade copper oxide ore in a certain place in Yunnan is first crushed and ground, and then the copper oxide mineral is recovered by a flotation test process of one roughing, three fines and three sweeps. In the flotation, a combined agent is used to synergistically capture the copper oxide ore. The mass ratio of benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate in the combined collector is 1.5:5. The experimental flow chart is as follows Figure 1 As shown, the specific steps are as follows:

[0040] (1) Crushing and grinding: The copper oxide ore is crushed and ground to a particle size of -74 μm, accounting for 76.52% by mass. The ore pulp after grinding is screened using a 32-mesh vibrating screen;

[0041] (2) Roughing: transport the -32 mesh qualified slurry in step (1) to an aerated flotation machine, adjust the slurry to a slurry mass concentration of 35%, and sequentially add 1300 g / t of inhibitor, 850 g / t of activator, 380 g / t of combined collector, and 30 g / t of frother to the adjusted slurry to perform a roughing operation to obtain a roughing concentrate and a roughing tailing;

[0042] (3) Scavenging: 350 g / t of activator, 220 g / t of combined collector and 25 g / t of frother are sequentially added to the primary roughing tailings of step (2) to carry out a primary scavenging operation to obtain a primary scavenging concentrate and a primary scavenging tailings; the primary scavenging concentrate is returned and incorporated into the primary roughing operation, and 250 g / t of activator, 110 g / t of combined collector and 15 g / t of frother are sequentially added to the primary scavenging tailings to carry out a secondary scavenging operation to obtain a secondary scavenging concentrate and a secondary scavenging tailings; the secondary scavenging concentrate is returned and incorporated into the primary scavenging operation, and 120 g / t of activator, 60 g / t of combined collector and 15 g / t of frother are sequentially added to the secondary scavenging tailings to carry out a tertiary scavenging operation to obtain a tertiary scavenging concentrate and a tertiary scavenging tailings; the tertiary scavenging concentrate is returned and incorporated into the secondary scavenging operation to form a closed loop, and the tertiary scavenging tailings are the final tailings;

[0043] (4) Concentration: Add 80 g / t of combined collector and 25 g / t of frother to the primary roughing concentrate of step (2) to carry out primary concentrating operation, and obtain primary concentrating concentrate and primary concentrating tailings; the primary concentrating tailings are returned and incorporated into the primary roughing operation, and 50 g / t of combined collector and 15 g / t of frother are added to the primary concentrating concentrate to carry out secondary concentrating operation, and obtain secondary concentrating concentrate and secondary concentrating tailings; the secondary concentrating tailings are returned and incorporated into the primary concentrating operation, and the secondary concentrating concentrate is subjected to three blank concentrating operations to obtain three times of concentrating concentrate and three times of concentrating tailings; the three times of concentrating tailings are returned and incorporated into the secondary concentrating operation, and the three times of concentrating concentrate is copper oxide concentrate. The test results of this embodiment are shown in Table 1.

[0044] Comparative Example 2: The low-grade copper oxide ore treated in this example is consistent with that in Example 2, and the treatment process is consistent with that in Example 2, except that the collector is amyl xanthate. The test results of this comparative example are shown in Table 2.

[0045] Embodiment 3: The low-grade oxidized copper ore treated in this embodiment is a low-grade oxidized copper ore from a place in Jiangxi Province. In the low-grade oxidized copper ore, the Cu grade is 0.69%, the SiO2 grade is 63.17%, the CaO grade is 12.79%, the MgO grade is 5.93%, and the Fe grade is 3.27%; the main useful minerals are chrysocolla and malachite, and the main gangue minerals are quartz, talc, clinochlore, diopside, and calcite; the mass percentage of copper is 42.73% for free copper oxide, 24.78% for combined copper oxide, 28.35% for primary copper sulfide, and 8.16% for secondary copper sulfide.

[0046] In this embodiment, low-grade copper oxide ore is first crushed and ground, and then the copper oxide mineral is recovered by a flotation test process of one roughing, three fines and three sweeps. In the flotation, a combination reagent is used to synergistically capture the copper oxide ore. The mass ratio of benzyl-N,N-dimethyldithiocarbamic acid and amyl xanthate in the combination reagent is 2:5. The test flow chart is as follows: Figure 1 As shown, the specific steps are as follows:

[0047] (1) Crushing and grinding: The copper oxide ore is crushed and ground to a particle size of -74 μm, accounting for 80% by mass. The ore pulp after grinding is screened using a 32-mesh vibrating screen;

[0048] (2) Roughing: transport the -32 mesh qualified slurry in step (1) to an aerated flotation machine, adjust the slurry to a slurry mass concentration of 40%, and sequentially add 1000 g / t of an inhibitor, 800 g / t of an activator, 250 g / t of a combined collector, and 20 g / t of a frother to the adjusted slurry to perform a roughing operation to obtain a roughing concentrate and a roughing tailing;

[0049] (3) Scavenging: 300 g / t of activator, 150 g / t of combined collector and 20 g / t of frother are sequentially added to the primary roughing tailings of step (2) to carry out primary scavenging operation, thereby obtaining primary scavenging concentrate and primary scavenging tailings; the primary scavenging concentrate is returned and incorporated into the primary roughing operation, and 200 g / t of activator, 80 g / t of combined collector and 20 g / t of frother are sequentially added to the primary scavenging tailings to carry out secondary scavenging operation, thereby obtaining secondary scavenging concentrate and secondary scavenging tailings; the secondary scavenging concentrate is returned and incorporated into the primary scavenging operation, and 150 g / t of activator, 40 g / t of combined collector and 10 g / t of frother are sequentially added to the secondary scavenging tailings to carry out tertiary scavenging operation, thereby obtaining tertiary scavenging concentrate and tertiary scavenging tailings; the tertiary scavenging concentrate is returned and incorporated into the secondary scavenging operation, and the tertiary scavenging tailings are the final tailings.

[0050] (4) Concentration: 50 g / t of combined collector and 20 g / t of frother were added to the primary roughing concentrate of step (2) to perform a primary concentration operation, and a primary concentrated concentrate and a primary concentrated tailing were obtained; the primary concentrated tailing was returned and incorporated into the primary roughing operation, and 30 g / t of combined collector and 10 g / t of frother were added to the primary concentrated concentrate to perform a secondary concentration operation, and a secondary concentrated concentrate and a secondary concentrated tailing were obtained; the secondary concentrated tailing was returned and incorporated into the primary concentration operation, and the secondary concentrated concentrate was subjected to a third blank concentration operation to obtain a third concentrated concentrate and a third concentrated tailing; the third concentrated tailing was returned and incorporated into the second concentration operation, and the third concentrated concentrate was a copper oxide concentrate. The test results of this embodiment are shown in Table 1.

[0051] Comparative Example 3: The low-grade copper oxide ore treated in this example is consistent with that in Example 3, and the treatment process is consistent with that in Example 3, except that the collector is amyl xanthate. The test results of this comparative example are shown in Table 2.

[0052] Table 1 Example flotation results

[0053]

[0054]

[0055] Table 2 Comparative Example Flotation Results

[0056]

[0057] It can be seen from Table 1 that in the flotation process of low-grade copper oxide ore, when the combined collector composed of the chelating agent benzyl-N,N-dimethyldithiocarbamic acid and butyl xanthate is used as the flotation collector, the grade of copper oxide concentrate is above 18%, and the recovery rate is above 80%, which effectively realizes the recovery of low-grade copper oxide ore.

[0058] From the data in Table 2 and Table 1, it can be seen that the flotation recovery rate and grade of low-grade copper oxide ore flotation by sulfide-xanthate method are not ideal. Therefore, in the flotation process of low-grade copper oxide ore, the synergistic collection system composed of a combined collector composed of chelating agent benzyl-N, N-dimethyldithiocarbamic acid and amyl xanthate can effectively solve the above problems and effectively recycle low-grade copper oxide ore.

[0059] The above description is only the preferred embodiment of the present invention and does not limit the present invention in any form. All modifications of various equivalent forms based on the technical essence of the present invention by those skilled in the art shall fall within the scope defined by the claims attached to this application.

Claims

1. Application of a combined collector in flotation of low-grade copper oxide ore, It is characterized in that The specific steps of the flotation are as follows: (1) Crushing and grinding: The copper oxide ore is crushed and ground to a particle size of -74 μm, which accounts for 70% to 80% by mass. The ore pulp after grinding is screened using a 32-mesh vibrating screen; (2) Roughing: transporting the qualified -32 mesh slurry in step (1) to an aerated flotation machine, adjusting the slurry to a slurry mass concentration of 20% to 40%, and sequentially adding a gangue inhibitor, an activator, a combined collector and a frother to the adjusted slurry to perform a primary roughing operation to obtain a primary roughing concentrate and a primary roughing tailings; (3) scavenging: adding an activator, a combined collector and a frother to the primary roughing tailings of step (2) in sequence to carry out a primary scavenging operation to obtain a primary scavenging concentrate and a primary scavenging tailings; the primary scavenging concentrate is returned and incorporated into the primary roughing operation, and an activator, a combined collector and a frother are added to the primary scavenging tailings in sequence to carry out a secondary scavenging operation to obtain a secondary scavenging concentrate and a secondary scavenging tailings; the secondary scavenging concentrate is returned and incorporated into the primary scavenging operation, and an activator, a combined collector and a frother are added to the secondary scavenging tailings in sequence to carry out a tertiary scavenging operation to obtain a tertiary scavenging concentrate and a tertiary scavenging tailings; the tertiary scavenging concentrate is returned and incorporated into the secondary scavenging operation, and the tertiary scavenging tailings are copper oxide tailings; (4) Concentration: adding a combined collector and a frother to the primary roughing concentrate of step (2) in sequence to perform a primary concentration operation, thereby obtaining a primary concentrated concentrate and a primary concentrated tailings; the primary concentrated tailings are returned and incorporated into the primary roughing operation, and a combined collector and a frother are added to the primary concentrated concentrate in sequence to perform a secondary concentration operation, thereby obtaining a secondary concentrated concentrate and a secondary concentrated tailings; the secondary concentrated tailings are returned and incorporated into the primary concentration operation, and the secondary concentrated concentrate is subjected to a third blank concentration operation, thereby obtaining a third concentrated concentrate and a third concentrated tailings; the third concentrated tailings are returned and incorporated into the second concentration operation, and the third concentrated concentrate is a copper oxide concentrate; The combined collector in steps (2) to (4) comprises a chelating agent and a xanthate collector, the mass ratio of the chelating agent to the xanthate collector is (1-2):5, the chelating agent is benzyl-N,N-dimethyldithiocarbamic acid; and the xanthate collector is amyl xanthate.

2. Application of the combined collector according to claim 1 in flotation of low-grade copper oxide ore, Features: The mass percentage of copper in the low-grade oxidized copper ore is 0.40% to 0.70%, and the low-grade oxidized copper ore contains at least one or more gangue minerals of diopside, calcite, talc, quartz, clinochlore and mica.

3. Application of the combined collector according to claim 1 in flotation of low-grade copper oxide ore, Features: The gangue inhibitor is water glass and sodium hexametaphosphate, the mass ratio of water glass to sodium hexametaphosphate is 3:1, the activator is sodium sulfide, the foaming agent is pine oil, the flotation reagents are all configured into an aqueous solution with a mass concentration of 5% before use, and the total amount of the combined collector added is 600-1200g / t.

4. Application of the combined collector according to claim 1 in flotation of low-grade copper oxide ore, Features: In the step (2) roughing operation, the amount of gangue inhibitor is 1000-1600 g / t, the amount of activator is 800-900 g / t, the amount of combined collector is 250-500 g / t, and the amount of foaming agent is 20-40 g / t. In the step (3) three scavenging operations, 300-400 g / t of activator, 150-300 g / t of combined collector, and 20-30 g / t of foaming agent are added to the first roughing tailings; 200-300 g / t of activator are added to the first scavenging tailings. 00g / t, combined collector 80-140g / t, frother 20-30g / t; add activator 100-150g / t, combined collector 40-80g / t, frother 10-20g / t to the secondary scavenging tailings; step (4) concentrating operation, add combined collector 50-120g / t, frother 20-30g / t to the primary roughing concentrate; add combined collector 30-60g / t, frother 10-20g / t to the primary concentrating concentrate.

Images