Pretreatment separation method of chalcopyrite-pyrite

Abstract

The invention discloses a chalcopyrite-pyrite pretreatment separation method. The method comprises the following steps: crushing, grinding and screening the composite mineral containing the chalcopyrite and the pyrite to obtain composite mineral powder with fine particle size; pouring the composite mineral powder into the heavy salt water, sealing, and standing for 2-4 days to obtain ore pulp; in the standing process, dissolved oxygen in the high-salt water seriously oxidizes the surface of the pyrite and generates a large number of hydrophilic substances, so that the floatability of the pyrite is inhibited; meanwhile, the surface of the chalcopyrite is slightly oxidized by dissolved oxygen in the high-salt water, and the floatability of the chalcopyrite is not affected; adding a collecting agent into the ore pulp, and uniformly stirring; and the ore pulp added with the collecting agent is subjected to air inflation flotation, and copper-containing concentrate is obtained through flotation. According to the method, agent pollution in the flotation process is reduced from the source, the flotation separation technological process of the chalcopyrite-pyrite is simplified, and the recovery rate and grade of the chalcopyrite in the concentrate are improved.

Description

Technical Field

[0001] The invention relates to the technical field of plate and strip rolling, and in particular to a pretreatment and separation method of chalcopyrite-pyrite. Background Art

[0002] Chalcopyrite is the main mineral source for extracting strategic copper metal, which is mainly obtained through flotation, separation and enrichment, but chalcopyrite generally coexists with pyrite. If the two minerals cannot be effectively separated during the flotation process, the copper grade in the flotated concentrate will be reduced. The reduction in copper grade not only reduces the economic value of the copper concentrate, but also makes the subsequent smelting process difficult, thereby increasing production costs and is not conducive to large-scale industrial applications.

[0003] Chalcopyrite and pyrite have similar flotation properties. Enhanced flotation separation is generally achieved by adding inhibitors (lime, sodium cyanide, etc.) or oxidants (hydrogen peroxide, etc.) to inhibit the floating of pyrite under alkaline conditions, thereby separating chalcopyrite. However, the amount of lime used is large, and the high alkaline conditions lead to increased foam viscosity, which in turn reduces the recovery rate and grade of chalcopyrite; sodium cyanide is toxic and is not conducive to actual industrial promotion; the oxidant H2O2 is expensive and has high storage requirements, and the cost of industrial practice is high; the water used for mineral processing also needs to be treated before it can be discharged or used, which increases environmental protection costs.

[0004] In addition, some plants far from fresh water have to use circulating water, groundwater, and even seawater and other high-salt water resources for flotation operations. High-salt water accounts for 97% of the total water resources, and the use of high-salt water for mineral flotation separation has certain application prospects.

[0005] In the prior art, Chinese patent CN 114074030 reduces the floatability of chalcopyrite and inhibits chalcopyrite by treating seawater for 14 to 28 days, thereby achieving flotation recovery of molybdenite. However, the high-salt water treatment time in this process is long, and a large amount of adjusting agent needs to be added to place the slurry in a strong alkaline environment, which increases the reagent cost and process flow, and does not involve the separation of pyrite; Chinese patent CN 114074032A achieves the separation of chalcopyrite and pyrite under weak alkaline conditions by adding oxidant H2O2 and adjusting agent NaOH; Chinese patent CN 114074031 A achieves the separation of copper-sulfur ore under pH=8 conditions by adding oxidant ferrate and adjusting agent NaOH; Chinese patent CN 110653075 B achieves copper mineral recovery by adding multiple reagents such as lime, sodium sulfide, Z-200 and pine oil for multiple flotation, and there are many types of reagents and a large amount of reagents used, which increases the process cost.

[0006] At present, the separation of chalcopyrite and pyrite through high-salt water pretreatment requires the addition of a large amount of inhibitors, regulators, or oxidants, which not only reduces the recovery rate and grade of chalcopyrite, but also pollutes the environment and increases the process cost. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention proposes a chalcopyrite-pyrite pretreatment separation method, in which no inhibitor, regulator or oxidant is added during the entire flotation process, which not only reduces the reagent pollution in the flotation process from the source, but also simplifies the flotation separation process of chalcopyrite-pyrite, improves the recovery rate and grade of chalcopyrite in the concentrate, and is a clean and pollution-free mineral pretreatment method.

[0008] In order to achieve the above object, the present invention is designed to separate chalcopyrite-pyrite pretreatment, which is characterized in that it comprises the following steps:

[0009] S1) crushing, grinding and screening the composite mineral containing chalcopyrite and pyrite to obtain composite mineral powder with fine particle size;

[0010] S2) pouring the composite mineral powder into high-salt water, sealing it, and letting it stand for 2 to 4 days to obtain a slurry;

[0011] During the static process, the dissolved oxygen in the high salt water seriously oxidizes the surface of pyrite and generates a large amount of hydrophilic substances, thereby inhibiting the floatability of pyrite; at the same time, the dissolved oxygen in the high salt water slightly oxidizes the surface of chalcopyrite and does not affect the floatability of chalcopyrite;

[0012] The chemical equation for the oxidation of pyrite is

[0013] 2FeS2+7O2+2H2O=2Fe 2+ +4SO4 2- +4H + ;

[0014] The chemical equation for the oxidation of chalcopyrite is

[0015] C U FeS2+4O2=C U 2+ +Fe 2+ +2SO4 2- ;

[0016] S3) adding a collector to the slurry obtained in step S2) and stirring the slurry uniformly;

[0017] The collector includes one or more of thiocarbamate, butyl xanthate or ethyl xanthate;

[0018] S4) aerating the ore pulp after adding the collector, most of the chalcopyrite and trace pyrite float up to become concentrate, most of the pyrite does not float out to become tailings, and the copper-containing concentrate obtained by flotation realizes the pretreatment separation of chalcopyrite and pyrite.

[0019] Furthermore, in S1), the particle size of the composite mineral powder is 0.038-0.075 mm.

[0020] Furthermore, in S2), the material ratio of the composite mineral powder to the high brine is 2-5 g:50-60 mL.

[0021] Furthermore, in S2), the high salt water includes Cl - 、SO4 2- , HCO 3- Br - 、Na + , K + , Ca + Mg 2+ , Cl - The concentration is 18.1~21.7g / L, SO4 2- The concentration is 2.5~3.0g / L, HCO3 - The concentration of Br is 0~0.1g / L, - The concentration is 0~0.1g / L, Na + The concentration of K is 10.3~10.9g / L, + The concentration of Ca is 0.4~0.8g / L, + The concentration is 0.4~0.8g / L, Mg 2+ The concentration is 1.2~1.5g / L.

[0022] Furthermore, in S3), the amount of the collector added is 1 to 10 mg / L.

[0023] Furthermore, in S4), a self-priming flotation machine is used to flush gas into the slurry for flotation, and the aeration rate is 3 to 7 mL / s.

[0024] The advantages of the present invention are:

[0025] 1. The present invention utilizes the characteristic that pyrite is more easily oxidized than chalcopyrite under high-salt water immersion conditions. By adjusting the high-salt water immersion time, the high-salt water causes the surface of pyrite to be severely oxidized and a large amount of hydrophilic substances to be generated, thereby inhibiting the floatability of pyrite, causing pyrite to enter the tailings during flotation; at the same time, under the same conditions, the high-salt water only slightly oxidizes the surface of chalcopyrite, does not affect the floatability of chalcopyrite, causes chalcopyrite to float out of the flotation and enter the concentrate, and finally realizes the flotation separation of chalcopyrite and pyrite;

[0026] 2. The present invention does not add any inhibitor, regulator or oxidant during the entire flotation process, only adds a trace amount of collector, and the flotation process is simple, which not only reduces the flotation cost, but also reduces the difficulty of subsequent treatment of mineral processing wastewater, saving manpower, material resources and financial resources to a certain extent;

[0027] 3. The present invention soaks pyrite and chalcopyrite with high salt water and pre-treats them for 2 to 4 days. The concentrate yield is as high as 57.63%, the copper grade in the concentrate is as high as 22.26%, the chalcopyrite recovery rate is as high as 94.91%, and the pyrite recovery rate is as low as 8.89%;

[0028] The chalcopyrite-pyrite pretreatment separation method of the present invention not only reduces the reagent pollution in the flotation process from the source, but also simplifies the flotation separation process of chalcopyrite-pyrite, improves the recovery rate and grade of chalcopyrite in the concentrate, and is a clean and pollution-free mineral pretreatment method. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a flow chart of the pretreatment separation method of chalcopyrite-pyrite of the present invention;

[0030] Figure 2 The comparison diagram of the recovery rate of chalcopyrite and the copper grade in the concentrate in the embodiment;

[0031] Figure 3 It is a comparison chart of the chalcopyrite recovery rate and the pyrite recovery rate in the embodiment. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0033] In the description of the present invention, it is necessary to understand that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the invention.

[0034] like Figure 1 As shown, a pretreatment separation method of chalcopyrite-pyrite of the present invention comprises the following steps:

[0035] S1) crushing, grinding and screening the composite mineral containing chalcopyrite and pyrite to obtain composite mineral powder with fine particle size.

[0036] Specifically, the particle size of the composite mineral powder is 0.038-0.075 mm.

[0037] In the following embodiments, the purity of chalcopyrite in the chalcopyrite raw material is 91.9%, of which Cu accounts for 24.99%, Fe accounts for 32.69%, and S accounts for 33.69%; the purity of pyrite in the pyrite raw material is 98.93%, of which Fe accounts for 46.13% and S accounts for 52.80%.

[0038] S2) Pour the composite mineral powder into high salt water, seal it, and let it stand for 2 to 4 days to obtain ore slurry.

[0039] During the static process, the dissolved oxygen in the high-salt water seriously oxidizes the surface of pyrite and generates a large amount of hydrophilic substances, thereby inhibiting the floatability of pyrite; at the same time, the dissolved oxygen in the high-salt water slightly oxidizes the surface of chalcopyrite and does not affect the floatability of chalcopyrite.

[0040] The chemical equation for the oxidation of pyrite is

[0041] 2FeS2+7O2+2H2O=2Fe 2+ +4SO4 2- +4H + ;

[0042] The chemical equation for the oxidation of chalcopyrite is

[0043] C U FeS2+4O2=C U 2+ +Fe 2+ +2SO4 2-

[0044] Specifically, the material ratio of the composite mineral powder to the high brine is 2-5 g:50-60 mL.

[0045] Specifically, the high salt water includes Cl - 、SO4 2- , HCO 3- Br - 、Na + , K + , Ca + Mg 2+ , Cl - The concentration is 18.1~21.7g / L, SO4 2- The concentration is 2.5~3.0g / L, HCO3 - The concentration of Br is 0~0.1g / L, - The concentration is 0~0.1g / L, Na + The concentration of K is 10.3~10.9g / L, + The concentration of Ca is 0.4~0.8g / L, + The concentration is 0.4~0.8g / L, Mg 2+The concentration is 1.2~1.5g / L.

[0046] Chalcopyrite and pyrite are naturally floatable in high-salt water, and pyrite is more easily oxidized than chalcopyrite under high-salt water immersion conditions.

[0047] S3) adding a collector to the slurry obtained in step S2) and stirring the slurry uniformly.

[0048] The collector includes one or more of thiocarbamate, butyl xanthate or ethyl xanthate.

[0049] Specifically, the added amount of the collector is 1 to 10 mg / L.

[0050] S4) aerating the ore pulp after adding the collector, most of the chalcopyrite and trace pyrite float up to become concentrate, most of the pyrite does not float out to become tailings, and the copper-containing concentrate obtained by flotation realizes the pretreatment separation of chalcopyrite and pyrite.

[0051] Specifically, a self-priming flotation machine is used to flush gas into the slurry for flotation, and the aeration rate is 3 to 7 mL / s.

[0052] The present invention utilizes the characteristic that pyrite is more easily oxidized than chalcopyrite under the condition of high-salt water immersion. By adjusting the high-salt water immersion time, the high-salt water causes the surface of pyrite to be severely oxidized and a large amount of hydrophilic substances to be generated, thereby inhibiting the floatability of pyrite and causing the pyrite to enter the tailings during flotation. At the same time, under the same conditions, the high-salt water only slightly oxidizes the surface of chalcopyrite and does not affect the floatability of chalcopyrite, causing the chalcopyrite to float out and enter the concentrate during flotation, thereby finally realizing the flotation separation of chalcopyrite and pyrite.

[0053] In addition, the present invention does not add any inhibitors, regulators and oxidants during the entire flotation process, only adds a trace amount of collectors, and the flotation process is simple, which not only reduces the flotation cost, but also reduces the difficulty of subsequent treatment of mineral processing wastewater, saving manpower, material resources and financial resources to a certain extent.

[0054] The following examples use simulated high-salt water to flotate pyrite and chalcopyrite. The ion composition and concentration range of the simulated high-salt water are similar to those of natural high-salt water. The main ion composition and concentration of the simulated high-salt water are shown in Table 1.

[0055] Table 1 Main ion components and concentrations of high salt water

[0056] Element Cl- <![CDATA[SO4 2- ]]> <![CDATA[HCO3 - ]]> <![CDATA[Br - ]]> <![CDATA[Na + ]]> <![CDATA[K + ]]> <![CDATA[Ca 2+ ]]> <![CDATA[Mg 2+ ]]> Concentration / g / L 18.1-21.7 2.5-3.0 0-0.1 0-0.1 10.3-10.9 0.4-0.8 0.4-0.8 1.2-1.5

[0057] Example 1

[0058] The mixed minerals of pyrite and chalcopyrite were poured into simulated high-salt water, and then sealed and allowed to stand for 3 days at room temperature to obtain slurry; the mass of the mixed minerals was 2.3 g, and the volume of the simulated high-salt water was 52 mL; the main ion components and concentrations of the simulated high-salt water used mainly included: 19.5 g / L Cl - , 2.7g / L SO4 2- , 0.1g / L HCO3 - , 10.4 g / L Na + , 0.4 g / L K + , 0.4 g / L Ca 2+ , 1.3 g / L Mg 2+ ;

[0059] 4 mg / L of butyl xanthate was added to the slurry obtained in the above steps, and then stirred for 6 minutes, followed by aeration flotation for 8 minutes to obtain concentrate products and tailings products. The products obtained by flotation were dried, weighed and chemically analyzed. The results are shown in Table 2.

[0060] Example 2

[0061] The mixed minerals of pyrite and chalcopyrite were poured into the simulated high-salt water, and then sealed and left to stand for 4 days at room temperature to obtain the slurry; the mass of the mixed minerals was 2.0 g, and the volume of the simulated high-salt water was 50 mL; the main ion components and concentrations of the simulated high-salt water used mainly included: 19.2 g / L Cl - , 2.4g / L SO4 2- , 0.1g / L HCO3 - , 0.1 g / L Br - , 10.6 g / L Na + , 0.4 g / L K + , 0.8 g / L Ca 2+ , 1.2 g / L Mg 2+ ;

[0062] 7 mg / L of ethyl xanthate was added to the slurry obtained in the above steps, and then stirred for 4 minutes, followed by aeration flotation for 12 minutes to obtain concentrate products and tailings products. The products obtained by flotation were dried, weighed and chemically analyzed. The results are shown in Table 2.

[0063] Example 3

[0064] The mixed minerals were poured into simulated high-salt water, and then sealed and allowed to stand for 2 days at room temperature to obtain a slurry; the mass of the mixed minerals was 2.4 g, and the volume of the simulated high-salt water was 60 mL; the main ion components and concentrations of the simulated high-salt water used mainly included: 19.6 g / L Cl - , 2.4g / L SO4 2- , 0.1g / L HCO3- , 0.1 g / L Br - , 10.8 g / L Na + , 0.4 g / L K + , 0.8 g / L Ca 2+ , 1.2 g / L Mg 2+ ;

[0065] 3 mg / L of thiocarbamate was added to the slurry obtained in the above steps, and then stirred for 3 minutes, followed by aeration flotation for 8 minutes to obtain concentrate products and tailings products. The products obtained by flotation were dried, weighed and chemically analyzed. The results are shown in Table 2.

[0066] Example 4

[0067] The mixed minerals were poured into simulated high-salt water, and then sealed and allowed to stand for 2 days at room temperature to obtain a slurry; the mass of the mixed minerals was 5.0 g, and the volume of the simulated high-salt water was 56 mL; the main ion components and concentrations of the simulated high-salt water used mainly included: 0.5400 mol / L Cl - , 0.0300mol / L SO4 2- , 0.0020 mol / L HCO 3- , 0.0009 mol / L Br - , 0.4620mol / L Na + , 0.0159 mol / L K + , 0.0150 mol / L Ca 2+ , 0.0550mol / L Mg 2+ ;

[0068] Thiocarbamate and butyl xanthate 4 mg / L were added to the slurry obtained in the above steps, and then stirred for 6 minutes, followed by aeration flotation for 12 minutes to obtain concentrate products and tailings products. The products obtained by flotation were dried, weighed and chemically analyzed. The results are shown in Table 2.

[0069] Comparative Example 1

[0070] The difference between this comparative example and Example 1 is that the standing time is 1 day. The results are shown in Table 2.

[0071] Comparative Example 2

[0072] The difference between this comparative example and Example 1 is that the standing time is 7 days. The results are shown in Table 2.

[0073] Table 2 Ore dressing test results of Examples 1 to 4 and Comparative Examples 1 to 2

[0074]

[0075] As can be seen from Table 2, the flotation method proposed in the present invention significantly improves the flotation separation effect of chalcopyrite and pyrite, and the copper grade in the concentrate and the recovery rate of chalcopyrite are significantly improved; the copper grade in the concentrate of Comparative Example 1 is low, and the difference in the recovery rates of the two minerals is small, and the flotation separation of chalcopyrite and pyrite cannot be achieved, indicating that the static oxidation time is too short, the oxidation degree of pyrite is low, and the inhibitory effect is not obvious, resulting in the pyrite floating into the concentrate, which significantly reduces the recovery rate and grade of chalcopyrite in the concentrate; Comparative Example 2 shows that the oxidation time is too long, the surfaces of chalcopyrite and pyrite are oxidized, and hydrophilic substances are produced, which are suppressed into the tailings during flotation, resulting in low recovery rate and copper grade of chalcopyrite in the concentrate, and poor flotation separation effect. For specific comparison diagrams, see the attached Figures 2-3 .

[0076] The chalcopyrite-pyrite pretreatment separation method of the present invention not only reduces the reagent pollution in the flotation process from the source, but also simplifies the flotation separation process of chalcopyrite-pyrite, improves the recovery rate and grade of chalcopyrite in the concentrate, and is a clean and pollution-free mineral pretreatment method.

[0077] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A pretreatment separation method for chalcopyrite-pyrite, characterized in that: The steps include: S1) crushing, grinding and screening the composite mineral containing chalcopyrite and pyrite to obtain composite mineral powder with fine particle size; S2) pouring the composite mineral powder into high-salt water, sealing it, and letting it stand for 2 to 4 days to obtain a slurry; During the static process, the dissolved oxygen in the high salt water seriously oxidizes the surface of pyrite and generates a large amount of hydrophilic substances, thereby inhibiting the floatability of pyrite; at the same time, the dissolved oxygen in the high salt water slightly oxidizes the surface of chalcopyrite and does not affect the floatability of chalcopyrite; The chemical equation for pyrite oxidation is 2FeS2+7O2+2H2O=2Fe 2+ +4SO4 2- +4H + ; The chemical equation for the oxidation of chalcopyrite is C U FeS2+4O2=C U 2+ +Fe 2+ +2SO4 2- ; S3) adding a collector to the slurry obtained in step S2) and stirring the slurry uniformly; The collector includes one or more of thiocarbamate, butyl xanthate or ethyl xanthate; S4) aerating the ore pulp after adding the collector, most of the chalcopyrite and trace pyrite float up to become concentrate, most of the pyrite does not float out to become tailings, and the copper-containing concentrate obtained by flotation realizes the pretreatment separation of chalcopyrite and pyrite.

2. The pretreatment separation method of chalcopyrite-pyrite according to claim 1, characterized in that: S1), the particle size of the composite mineral powder is 0.038-0.075 mm.

3. The pretreatment separation method of chalcopyrite-pyrite according to claim 2, characterized in that: In S2), the material ratio of the composite mineral powder to the high brine is 2-5 g:50-60 mL.

4. The pretreatment separation method of chalcopyrite-pyrite according to claim 3, characterized in that: S2), the high salt water includes Cl - 、SO4 2- , HCO 3- Br - 、Na + , K + , Ca + Mg 2+ , Cl - The concentration is 18.1~21.7g / L, SO4 2- The concentration is 2.5~3.0g / L, HCO3 - The concentration of Br is 0~0.1g / L, - The concentration is 0~0.1g / L, Na + The concentration of K is 10.3~10.9g / L, + The concentration of Ca is 0.4~0.8g / L, + The concentration is 0.4~0.8g / L, Mg 2+ The concentration is 1.2~1.5g / L.

5. The pretreatment separation method of chalcopyrite-pyrite according to claim 1, characterized in that: In S3), the amount of the collector added is 1 to 10 mg / L.

6. The pretreatment separation method of chalcopyrite-pyrite according to claim 5, characterized in that: In S4), a self-priming flotation machine is used to flush gas into the slurry for flotation, and the aeration rate is 3 to 7 mL / s.

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