A beneficiation method of low-grade lead-antimony-zinc sulfide ore

Abstract

The application discloses a beneficiation method for low-grade lead-antimony-zinc sulfide ore, which comprises the following steps: two rough selections, two selections, two sweep selections and one magnetic selection, and the specific process is as follows: grinding-lead-antimony rough selection-zinc rough selection-lead-antimony selection-magnetic selection-zinc selection-lead-antimony sweep selection-zinc sweep selection. The method is used for recovering lead, antimony and zinc from low-grade lead-antimony-zinc sulfide ore through two rough selections, two selections, two sweep selections and one magnetic selection. Lead and antimony are recovered through flotation, and then the lead-antimony concentrate after flotation is subjected to magnetic selection, so that the recovery rate of the lead-antimony concentrate is improved, and the overall recovery rate of lead and antimony is above 80%. The zinc flotation operation and the lead-antimony flotation operation are alternately performed, so that the recovery rate of zinc is improved, and the overall recovery rate of zinc is above 85%.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, specifically to a method for beneficiating low-grade lead-antimony-zinc sulfide ores. Background Technology

[0002] my country has abundant lead, antimony, and zinc mineral resources. However, with the continuous depletion of these resources, high-grade, easily mined, and easily beneficiated ores are becoming increasingly scarce and facing depletion. Meanwhile, low-grade, difficult-to-mine lead-antimony-zinc sulfide ores containing lead, antimony, and zinc, with high levels of impurities such as iron, copper, sulfur, and arsenic, and complex mineral compositions, have gradually become an important source of raw materials for the lead-antimony-zinc beneficiation industry. Lead-antimony-zinc sulfide ores contain a wide variety of minerals. Lead and antimony mainly exist as brittle antimony sulfide, while zinc mainly exists as sphalerite. The minerals are closely interdependent, with the main metals having fine grain sizes and containing varying amounts of other impurity elements.

[0003] Brittle stibnite, also known as "feather ore," is a sulfide mineral, lead-gray in color, opaque, with a metallic luster, and very soft. Its Mohs hardness is 2.5–3, and its specific gravity is 5.6. The mineral occurs as massive and feather-like aggregates. Due to its columnar or acicular to fibrous crystal morphology, it is called "feather ore." It is mainly found in polymetallic hydrothermal deposits and can be used as a mineral raw material for refining lead and antimony. Currently, the main processing methods for brittle stibnite include sodium sulfate leaching-diaphragm electrowinning, new chlorination-hydrolysis, chloride salt chlorination-low-temperature dry distillation, selective chlorination, slurry electrolysis, steam-air oxidation volatilization roasting, and fluidized bed roasting-reduction smelting. Among these, the main method for processing brittle stibnite concentrate remains the pyrometallurgical process, namely, fluidized bed roasting and desulfurization – blast furnace reduction smelting – reverberatory furnace oxidation blowing and then reduction smelting. Brittle antimony-lead concentrate is desulfurized by roasting in a fluidized bed furnace, followed by secondary sintering of the roasted sand and reduction smelting in a blast furnace to produce a lead-antimony alloy. The lead-antimony alloy is then oxidized and smelted in a reverberatory furnace to obtain antimony oxide powder and bottom lead, thus separating the lead and antimony. The antimony oxide powder is further reduced and refined in a reverberatory furnace to produce refined antimony. The bottom lead is then electrolyzed using lead fluorosilicate to produce electrolytic lead, while silver is enriched in the anode mud for recovery. However, this method has drawbacks such as high material return during smelting, a long process flow, low metal recovery rate, and environmental pollution.

[0004] Patent CN201210090831.3 discloses a method for separating lead and antimony from brittle sulfide ore. Based on the unique molecular composition of brittle sulfide ore, by controlling appropriate heating and condensation temperatures and utilizing the special environment of a vacuum, galena and stibnite are volatilized and condensed separately, thus effectively separating lead and antimony. This invention can directly process brittle sulfide ore to obtain galena and stibnite; however, lead-antimony-zinc mineral deposits not only include brittle sulfide ore but also other metallic minerals such as sphalerite. Simply performing vacuum smelting cannot separate these other metallic minerals.

[0005] Patent CN201010518066.1 discloses a method for separating and flotating low-grade complex lead, antimony, and zinc sulfide ores. It relates to a new method for flotation of lead, antimony, and zinc sulfide ores, specifically targeting the separation of low-grade complex and difficult-to-separate lead, antimony, and zinc sulfide ores. It adopts a method of simultaneous separation and washing, integrating separation and washing into one process. This method removes the interference of harmful ions, reagents, and slime in the slurry on the separation of low-grade lead, antimony, and zinc. Although this method can effectively separate lead, antimony, and zinc by flotation, it requires continuous water washing, which can easily lead to water waste.

[0006] As mineral resources become increasingly depleted, the amount of usable resources will continue to decrease. Therefore, expanding resource utilization or comprehensively recovering secondary resources will be an important source of resources for the mineral processing industry. How to efficiently process low-grade ores is of great significance. Summary of the Invention

[0007] The purpose of this invention is to provide a beneficiation method for low-grade lead-antimony-zinc sulfide ore that efficiently recovers lead-antimony and zinc by performing flotation operations on lead-antimony and zinc separately and combining the flotation process with magnetic separation, in order to solve the technical problem of low flotation separation and recovery efficiency of lead-antimony-zinc.

[0008] To solve the above technical problems, the present invention adopts the following solution: A beneficiation method for low-grade lead-antimony-zinc sulfide ore includes the following steps: (1) Grinding: The ore is classified by ball mill and spiral classifier, and the ore is ground to -200 mesh, accounting for 85~95%. The ore that is too large after classification is recycled to the ball mill for re-grinding. (2) Lead-antimony roughing: Add zinc mineral inhibitor ZnSO4 and sodium sulfite, lead-antimony collector SN-9 and frother No. 2 oil to the slurry after grinding and classification for flotation to obtain lead-antimony roughing froth and lead-antimony roughing tailings; (3) Zinc roughing: Add iron mineral inhibitor y-As and lime, activator copper sulfate, collector butyl xanthate and frother No. 2 oil to lead-antimony roughing tailings for flotation to obtain zinc roughing froth and zinc roughing tailings; (4) Lead-antimony refining: Add zinc mineral inhibitor ZnSO4 and sodium sulfite, lead-antimony collector SN-9, frother No. 2 oil and lead-antimony activator sulfuric acid to the lead-antimony roughing froth in step (2) for reflotation to obtain lead-antimony concentrate; (5) Magnetic separation: The lead-antimony flotation foam from step (4) is subjected to magnetic separation using a magnetic separator to obtain lead-antimony concentrate with higher purity; (6) Zinc Refinement: Add iron mineral inhibitor γ-As and lime, activator copper sulfate, collector butyl xanthate and frother No. 2 oil to the zinc roughing froth for reflotation to obtain zinc concentrate; (7) Lead-antimony scavenging: Add zinc mineral inhibitor ZnSO4 and sodium sulfite, lead-antimony collector SN-9, frother No. 2 oil and lead-antimony activator sulfuric acid to the zinc roughing tailings in step (3) for scavenging to obtain a small amount of lead-antimony concentrate and scavenged tailings; (8) Zinc scavenging: Add iron mineral inhibitor y-As and lime, activator copper sulfate, collector butyl xanthate and frother No. 2 oil to the scavenging tailings for reflotation to obtain zinc concentrate and tailings.

[0009] Furthermore, the dosages in step (2) are 800~1300g / t of zinc mineral inhibitor ZnSO4, 300~700g / t of sodium sulfite, 50~100g / t of lead-antimony collector SN-9, and 60~100g / t of foaming agent No. 2 oil.

[0010] Furthermore, in steps (4) and (7), the zinc mineral inhibitor ZnSO4 and sodium sulfite are both 300~700g / t, the lead-antimony collector SN-9 (ethyl thiocyanate) is 50~100g / t, the foaming agent No. 2 oil is 60~100g / t, and the lead-antimony activator sulfuric acid is 800~1500g / t.

[0011] Furthermore, the amounts used in steps (3), (6), and (8) are 150-300 g / t of iron mineral inhibitor y-As, 6000 g / t of lime, 150-300 g / t of activator copper sulfate, 50-150 g / t of collector butyl xanthate, and 60-100 g / t of foaming agent No. 2 oil, respectively.

[0012] Furthermore, the magnetic field strength in step (5) is in the range of 100~120 Ka•m. -1 After zinc selection in step (6), zinc magnetic separation is performed.

[0013] Furthermore, the collector is 25# black powder plus CSU11, with a dosage of 50~200g / t.

[0014] The beneficial effects of this invention are as follows: 1. This invention utilizes two roughing, two cleaning, two scavenging, and one magnetic separation process to recover lead, antimony, and zinc from low-grade lead-antimony-zinc sulfide ores. For lead and antimony recovery, flotation is performed first, followed by magnetic separation of the flotation concentrate to improve the recovery rate of the lead and antimony concentrate, achieving an overall lead and antimony recovery rate of over 80%. Zinc flotation is performed alternately with lead and antimony flotation to improve the zinc recovery rate, achieving an overall zinc recovery rate of over 85%.

[0015] 2. In this invention, both lead-antimony collectors and zinc collectors can be 25# black powder plus CSU11. CSU11 has better selectivity, while 25# black powder has stronger collecting ability. The combination of 25# black powder and CSU11 has a stronger collecting ability and better selectivity for lead-antimony minerals and zinc minerals compared to traditional collectors. Detailed Implementation

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] The following is a further detailed description of the beneficiation method for low-grade lead-antimony-zinc sulfide ore according to the present invention: Example 1

[0018] A beneficiation method for low-grade lead-antimony-zinc sulfide ore includes the following steps: (1) Grinding: Low-grade lead-antimony-zinc sulfide ore is ground and dissociated. The ore is classified by ball mill and spiral classifier. The ore is ground to about 85% of -200 mesh. The spiral classifier and ball mill are matched to form a closed-loop circulation process for the slurry to be divided and diverted. The ore with larger particle size after classification is recycled to the ball mill for re-grinding. (2) Lead-antimony roughing: Add 1000g / t of zinc mineral inhibitor ZnSO4, 500g / t of sodium sulfite, 60g / t of lead-antimony collector SN-9, and 80g / t of frother No. 2 oil to the slurry after grinding and classification for flotation to obtain lead-antimony roughing froth and lead-antimony roughing tailings. (3) Zinc roughing: Add 200g / t of iron mineral inhibitor y-As, 6000g / t of lime, 200g / t of copper sulfate activator, 100g / t of butyl xanthate collector, and 80g / t of No. 2 oil frother to lead-antimony roughing tailings for flotation to obtain zinc roughing froth and zinc roughing tailings. (4) Lead-antimony refining: Add 500g / t of zinc mineral inhibitor ZnSO4 and 500g / t of sodium sulfite, 60g / t of lead-antimony collector SN-9, 80g / t of frother No. 2 oil and 1000g / t of lead-antimony activator sulfuric acid to the lead-antimony roughing froth in step (2) for reflotation to obtain lead-antimony concentrate with a lead-antimony recovery rate of more than 83%; (5) Magnetic separation: The lead-antimony flotation foam from step (4) is subjected to magnetic separation using a magnetic separator. The magnetic field strength of the magnetic separator is adjusted to 110KA / m to obtain lead-antimony concentrate with higher purity and lead-antimony recovery rate greater than 95%. (6) Zinc Refinement: Add 200g / t of iron mineral inhibitor y-As, 6000g / t of lime, 230g / t of copper sulfate activator, 120g / t of butyl xanthate collector, and 80g / t of No. 2 oil frother to the zinc roughing froth for reflotation to obtain zinc concentrate with a zinc recovery rate of more than 85%; (7) Lead-antimony scavenging: Add 500g / t of zinc mineral inhibitor ZnSO4 and 500g / t of sodium sulfite, 60g / t of lead-antimony collector SN-9, 80g / t of frother No. 2 oil and 800g / t of lead-antimony activator sulfuric acid to the zinc roughing tailings in step (3) for scavenging to obtain a small amount of lead-antimony concentrate and scavenged tailings; (8) Zinc scavenging: Add 180g / t of iron mineral inhibitor y-As, 6000g / t of lime, 200g / t of copper sulfate activator, 100g / t of butyl xanthate collector, and 80g / t of No. 2 oil frother to the scavenging tailings for reflotation to obtain zinc concentrate and tailings. Example 2

[0019] The difference from Example 1 is that after zinc refining in step (6), zinc magnetic separation is performed. A magnetic separator is used to perform magnetic separation on the zinc concentrate from step (6). The magnetic field strength of the magnetic separator is adjusted to 120KA / m to obtain zinc concentrate with higher purity and a zinc recovery rate greater than 95%. In step (2), the dosage of lead-antimony roughing is 1200g / t of zinc mineral inhibitor ZnSO4 and 600g / t of sodium sulfite, 50g / t of lead-antimony collector SN-9, and 60g / t of frother No. 2 oil. In step (4) lead-antimony refining and step (7) lead-antimony scavenging, the dosage of zinc mineral inhibitor ZnSO4 and sodium sulfite is 700g / t, the dosage of lead-antimony collector SN-9 is 80g / t, the dosage of frother No. 2 oil is 60g / t, and the dosage of lead-antimony activator sulfuric acid is 1200g / t. The lead-antimony recovery rate is greater than 90%. The amounts used in step (3) zinc roughing, step (6) zinc fine selection and step (8) zinc scavenging are 150 g / t of iron mineral inhibitor y-As and 6000 g / t of lime, 150 g / t of activator copper sulfate, 75 g / t of collector butyl xanthate and 60 g / t of foaming agent No. 2 oil, respectively; the zinc recovery rate is greater than 85%. Example 3

[0020] The difference from Example 2 is that the lead-antimony collector is 65g / t of 25# black powder plus 100g / t of CSU11, with a lead-antimony recovery rate greater than 85%; and the zinc collector is 60g / t of 25# black powder plus 120g / t of CSU11, with a zinc recovery rate greater than 85%.

[0021] All the drugs used in the examples are mining reagents, which are commercially available.

[0022] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A beneficiation method for low-grade lead-antimony-zinc sulfide ore, characterized in that: Includes the following steps: (1) Grinding: The ore is classified by ball mill and spiral classifier, and the ore is ground to -200 mesh, accounting for 85~95%. The ore that is too large after classification is recycled to the ball mill for re-grinding. (2) Lead-antimony roughing: Add zinc mineral inhibitor ZnSO4 and sodium sulfite, lead-antimony collector SN-9 and frother No. 2 oil to the slurry after grinding and classification for flotation to obtain lead-antimony roughing froth and lead-antimony roughing tailings; (3) Zinc roughing: Add iron mineral inhibitor y-As and lime, activator copper sulfate, collector butyl xanthate and frother No. 2 oil to lead-antimony roughing tailings for flotation to obtain zinc roughing froth and zinc roughing tailings; (4) Lead-antimony refining: Add zinc mineral inhibitor ZnSO4 and sodium sulfite, lead-antimony collector SN-9, frother No. 2 oil and lead-antimony activator sulfuric acid to the lead-antimony roughing froth in step (2) for reflotation to obtain lead-antimony concentrate; (5) Magnetic separation: The lead-antimony flotation froth from step (4) is subjected to magnetic separation using a magnetic separator to obtain lead-antimony concentrate with higher purity; the magnetic field strength range of the magnetic separation in step (5) is 100~120 Ka•m. -1 ; (6) Zinc Refinement: Add iron mineral inhibitor γ-As and lime, activator copper sulfate, collector butyl xanthate and frother No. 2 oil to the zinc roughing froth for reflotation to obtain zinc concentrate; after zinc refinement in step (6), zinc magnetic separation is carried out; (7) Lead-antimony scavenging: Add zinc mineral inhibitor ZnSO4 and sodium sulfite, lead-antimony collector SN-9, frother No. 2 oil and lead-antimony activator sulfuric acid to the zinc roughing tailings in step (3) for scavenging to obtain a small amount of lead-antimony concentrate and scavenged tailings; (8) Zinc scavenging: Add iron mineral inhibitor y-As and lime, activator copper sulfate, collector butyl xanthate and frother No. 2 oil to the scavenging tailings for reflotation to obtain zinc concentrate and tailings.

2. The beneficiation method for low-grade lead-antimony-zinc sulfide ore according to claim 1, characterized in that: The dosages in step (2) are 800~1300g / t of zinc mineral inhibitor ZnSO4, 300~700g / t of sodium sulfite, 50~100g / t of lead-antimony collector SN-9, and 60~100g / t of foaming agent No. 2 oil.

3. The beneficiation method for low-grade lead-antimony-zinc sulfide ore according to claim 1, characterized in that: In steps (4) and (7), the zinc mineral inhibitor ZnSO4 and sodium sulfite are 300~700g / t, the lead-antimony collector SN-9 is 50~100g / t, the foaming agent No. 2 oil is 60~100g / t, and the lead-antimony activator sulfuric acid is 800~1500g / t.

4. The beneficiation method for low-grade lead-antimony-zinc sulfide ore according to claim 1, characterized in that: The amounts used in steps (3), (6) and (8) are 150-300 g / t of iron mineral inhibitor y-As, 6000 g / t of lime, 150-300 g / t of activator copper sulfate, 50-150 g / t of collector butyl xanthate, and 60-100 g / t of foaming agent No. 2 oil, respectively.

5. The beneficiation method for low-grade lead-antimony-zinc sulfide ore according to claim 1, characterized in that: The lead-antimony collector is 25# black powder plus CSU11, with a dosage of 50~200g / t.