Iron-zinc separation and enrichment beneficiation method for zinc-containing magnetite concentrate

Abstract

The invention discloses an iron-zinc separation and enrichment beneficiation method for zinc-containing magnetite concentrate, which comprises the following steps of: firstly, carrying out zinc-sulfur bulk flotation on the zinc-containing magnetite concentrate by using copper sulfate as an activating agent, using a mixed drug of BK606, BK608 and butyl xanthate as a collecting agent and using 2 # oil as a foaming agent to obtain the content lt of Zn; the content of magnetite concentrate is 0.08%, and the content of zinc-sulfur bulk concentrate is 2.7%-3.3%; and the obtained zinc-sulfur bulk concentrate is subjected to ore grinding operation, discharged zinc-sulfur bulk concentrate grinding products are subjected to zinc-sulfur separation flotation operation, zinc concentrate with the Zn content being larger than or equal to 40% and zinc separation tailings with the zinc content being smaller than or equal to 0.55% are obtained, and the zinc separation tailings and magnetite concentrate are combined into final iron concentrate with the zinc content being smaller than or equal to 0.095%. According to the method, under the condition that the zinc content of the iron ore concentrate is only 0.16%, the zinc concentrate product with the zinc grade larger than 40.0% is obtained, the enrichment ratio reaches up to 250 times, the loss of the iron ore concentrate yield is reduced to the maximum extent, and the loss of the iron ore concentrate yield is only 0.17%.

Description

Technical Field

[0001] The invention belongs to the technical field of iron ore beneficiation, and specifically relates to a separation method for zinc-containing iron concentrate, which is particularly suitable for processing iron-zinc separation, separation and enrichment of zinc-containing iron concentrate with a TFe grade between 65% and 67% and a Zn content between 0.10% and 0.20%. Background Art

[0002] Excessive Zn content in iron ore is not conducive to smelting. About 10% of the zinc in the iron ore concentrate in the blast furnace is removed during the sintering process, and the rest exists mostly in the state of ZnO, and a small amount is ferrite compounds, which enter the blast furnace with the sintered ore. Due to its high melting point, it is difficult to be melted directly in the blast furnace, which has a great harm to the blast furnace and subsequent smelting. It is generally required to reduce the Zn content in the iron ore concentrate to less than 0.1%.

[0003] The following process is usually used to reduce zinc in iron ore concentrate:

[0004] (1) Grinding-single magnetic separation process. Chinese patent CN 110947516 A discloses a method for reducing zinc in iron concentrate: by subjecting zinc tailings to weak magnetic roughing-grinding-weak magnetic concentration 1-weak magnetic concentration 2, and grinding to -400 mesh 80%, the zinc content in the iron concentrate is reduced from 0.09% to 0.068%, which is a small reduction. In addition, the zinc content of the iron concentrate of 0.09% has met the requirement of smelting that the zinc content of the iron concentrate is less than 0.1%, so it seems unnecessary to reduce the zinc content to 0.068%.

[0005] (2) Single flotation process. Chinese patent CN 113477405 B discloses an activator for the beneficiation of sphalerite and sphalerite and a method for flotation reduction of zinc in iron concentrate: amino acids containing multiple ligands are preferably used as activators to increase the depth of zinc removal. Although deep zinc removal in iron concentrate can be achieved, strict requirements are also imposed on the zinc grade (<0.1%), and it is not applicable to iron concentrate with high zinc content.

[0006] (3) Float-magnetic combined process: Chinese patent CN 115582209 A discloses a method for improving the quality of high-zinc iron concentrate and reducing silicon to prepare high-purity iron concentrate: the high-zinc iron concentrate is ground and then subjected to flotation and zinc selection, a coarse, two-fine and three-sweep closed-circuit flotation process, and zinc tailings weak magnetic separation to obtain low-zinc high-purity iron concentrate. This method is to obtain high-purity iron concentrate, but is not suitable for reducing zinc in ordinary iron concentrate. In Example 1, a certain weak magnetic separation iron concentrate has a zinc content of 0.416%, an iron content of 65.05%, and an SiO2 content of 4.56%. By using this patented method, the zinc content in the iron concentrate is significantly reduced, but at the same time, the iron concentrate yield is lost by 7.65%; in Example 2, a certain weak magnetic separation iron concentrate has a zinc content of 0.356%, an iron content of 64.05%, and an SiO2 content of 5.56%. By using this patented method, the iron concentrate yield is lost by 8.95%. The iron concentrate yield loss in the two embodiments is very large, which means that the output of iron concentrate will be greatly reduced. Under the premise that iron ore mining and processing enterprises generally maintain output, it is almost unacceptable to significantly reduce output in order to reduce zinc. Moreover, general iron ore mining and processing enterprises do not need to produce high-purity iron concentrate. As far as the domestic market is concerned, the market demand for both high-purity iron concentrate and ultra-pure iron concentrate is small, and blindly pursuing high-quality iron concentrate is not meaningful. Summary of the invention

[0007] The purpose of the present invention is to provide a method for separating, enriching and beneficiating zinc from zinc-containing magnetite concentrate, in order to solve the technical problems that the current zinc removal process for zinc-containing iron concentrate has a high iron loss rate, strict requirements on the zinc grade, a small reduction in zinc content in the iron concentrate, and no zinc concentrate can be obtained after sorting.

[0008] To achieve the above-mentioned purpose of the present invention, the present invention provides a method for separating and enriching zinc from zinc-containing magnetite concentrate, which is used to separate and enrich zinc from zinc-containing iron concentrate with a TFe grade of 65% to 67% and a Zn content of 0.10% to 0.20%, and is specifically implemented by the following processes and steps:

[0009] S1 zinc-sulfur mixed flotation of zinc-containing magnetite concentrate

[0010] Firstly, zinc-sulfur mixed flotation is performed on the zinc-containing magnetite concentrate to obtain a magnetite concentrate with a Zn content of less than 0.08% and a zinc-sulfur mixed concentrate containing 2.7% to 3.3% zinc; the zinc-sulfur mixed flotation adopts a primary roughing, copper sulfate is used as an activator, a mixture of BK606, BK608 and butyl xanthate is used as a collector, and 2# oil is used as a frother;

[0011] S2 zinc-sulfur mixed concentrate grinding

[0012] The zinc-sulfur mixed concentrate obtained in step S1 is fed into the grinding operation, and the particle size of the grinding product is controlled at -0.076 mm, with the mass accounting for 91% to 97%;

[0013] S3 zinc-sulfur mixed concentrate grinding product zinc-sulfur separation flotation

[0014] The zinc-sulfur mixed concentrate grinding product discharged from step S2 is fed into zinc-sulfur separation flotation operation to obtain zinc concentrate with Zn content ≥40% and zinc tailings with zinc content ≤0.55%. The zinc tailings are combined with the magnetite concentrate from step S1 to form a final iron concentrate with zinc content ≤0.095%. The zinc-sulfur separation flotation operation adopts 1 roughing selection, 1 scavenging selection and 3 to 5 cleaning selections, lime is used as pH adjuster and inhibitor, copper sulfate is used as zinc-containing mineral activator, and MK-306 is used as collector.

[0015] Preferably, in step S1, according to the amount of dry ore fed to the flotation ore, the dosage of the reagents is: 100-300 g / t of copper sulfate, 100-200 g / t of BK606, 100-200 g / t of BK608, 25-75 g / t of butyric acid, and 40-60 g / t of frother 2 oil. The mass ratio of BK606, BK608, and butyric acid is preferably (2.5-3.5): (2.5-3.5): 1, and 3:3:1 is optimal.

[0016] Preferably, in step S3, the zinc-sulfur separation flotation operation adopts 1 roughing, 1 scavenging and 4 concentrating operations, and the middling ore is returned in a "semi-concentrated-semi-sequential" manner, that is, the concentrate 1 tailings and the scavenging 1 concentrate are sequentially returned to the roughing operation, and the concentrating 2 tailings, concentrating 3 tailings and concentrating 4 tailings are concentratedly returned to the concentrating 1 operation.

[0017] Preferably, in step S3, the flotation roughing operation uses lime as a pH adjuster and inhibitor, copper sulfate as an activator for zinc-containing minerals, and MK-306 as a collector; the flotation scavenging operation uses MK-306 as a collector; the selection 1 operation uses lime as a pH adjuster and inhibitor, and copper sulfate as an activator for zinc-containing minerals; the selection 2 operation, the selection 3 operation, and the selection 4 operation all use lime as a pH adjuster and inhibitor, and MK-306 as a collector, respectively.

[0018] Preferably, in step S3, based on the amount of dry ore fed to the flotation feed, the dosage of the flotation roughing agent is: 3500-4500 g / t of lime, 500-700 g / t of copper sulfate, and 100-150 g / t of collector MK306; the dosage of the flotation scavenging agent is: 50-70 g / t of MK306.

[0019] Preferably, in step S3, based on the amount of dry ore fed to the flotation ore, the amount of lime used in the selection operation 1 is 2000-4000 g / t, and the amount of copper sulfate is 40-60 g / t; the amount of lime used in the selection operation 2 is 1200-1800 g / t, and the amount of MK306 is 15-25 g / t; the amount of lime used in the selection operation 3 is 700-900 g / t, and the amount of MK306 is 5-15 g / t; the amount of lime used in the selection operation 4 is 700-900 g / t, and the amount of MK306 is 5-15 g / t.

[0020] The specific values ​​of the above-mentioned parameters such as flotation times and reagent dosage can be determined based on the properties of the ore and the results of laboratory tests.

[0021] The three collectors BK606, BK608 and MK-306 used in the iron-zinc separation, enrichment and beneficiation method of zinc-containing magnetite concentrate of the present invention are briefly described as follows:

[0022] BK608: Yellow liquid, non-irritating odor, belongs to general chemicals, has strong capture power, excellent flotation index characteristics, has better flotation performance than xanthate, can completely replace xanthate, produced by Beikuang Chemical Technology (Cangzhou) Co., Ltd.

[0023] BK608: BK606: Brown liquid, no irritating odor, belongs to general chemicals, copper sulfide mineral collector, has good selectivity, produced by Beikuang Chemical Technology (Cangzhou) Co., Ltd.

[0024] MK-306: Brown-yellow transparent liquid, a highly efficient collector for nonferrous metal sulfide ores, with self-foaming properties, mostly used for the flotation of copper sulfide ores, lead-zinc ores, gold-silver ores, and pyrites. It is easy to use, has little odor, has strong collecting power, and has good flotation indexes. It is produced by China Steel Ma'anshan Mining Research Institute Co., Ltd.

[0025] Compared with the prior art, the iron-zinc separation and enrichment beneficiation method of zinc-containing magnetite concentrate of the present invention has the following advantages:

[0026] (1) Considering that the zinc grade in the zinc-sulfur mixed flotation concentrate fluctuates greatly during production, the intermediate ore of the zinc-sulfur separation process (one roughing, four fines, one scavenging closed-circuit flotation process) of the present invention adopts a "semi-centralized-semi-sequential" return method, and the intermediate ore of the selected 2, selected 3, and selected 4 in the selected stage is concentrated and returned to the selected 1, thereby avoiding the influence of the sequential return of the intermediate ore on the zinc concentrate grade; the tailings of the selected 1 and the scavenging concentrate are sequentially returned to the roughing to ensure the recovery rate of zinc metal.

[0027] (2) In zinc-sulfur mixed flotation, a compound mixture of BK606, BK608 and butyl xanthate is used as a collector to exert a "synergistic effect" and minimize the zinc content of the mixed flotation tank bottom product; the selective collector MK 306 is used for zinc-sulfur separation, which greatly improves the grade of zinc concentrate.

[0028] (3) Under the condition that the zinc content in the zinc magnetite concentrate is only 0.10% to 0.20%, a zinc concentrate product with a zinc grade greater than 40.0% is obtained, and the zinc enrichment ratio is as high as more than 250 times, achieving unexpected technical results.

[0029] (4) The zinc content in the final iron ore concentrate is reduced to below 0.095%, which minimizes the loss of iron ore concentrate yield. The loss of iron ore concentrate yield is less than 0.2%, which solves the contradiction between zinc reduction in iron ore concentrate and loss of iron ore concentrate yield to the greatest extent, and achieves unexpected technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 The present invention is a mineral processing process flow chart of an embodiment of an iron-zinc separation, enrichment and mineral processing method for zinc-containing magnetite concentrate.

[0031] Figure 2 The present invention is a full-process numerical and mass flow chart of an embodiment of an iron-zinc separation, enrichment and beneficiation method for zinc-containing magnetite concentrate. DETAILED DESCRIPTION

[0032] To further describe the present invention, the iron-zinc separation, enrichment and beneficiation method of zinc-containing magnetite concentrate of the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be noted that any modification, equivalent replacement, improvement, etc. made within the technical ideas and principles of the present invention should be included in the protection scope of the present invention.

[0033] The chemical multi-element analysis results of the zinc-containing magnetite concentrate used in this example are shown in Table 1, and the zinc phase analysis results are shown in Table 2.

[0034] Table 1 Chemical multi-element analysis results of zinc-containing magnetite concentrate

[0035] Test items TFe <![CDATA[SiO2]]> <![CDATA[Al2O3]]> CaO MgO content(%) 65.01 4.10 1.71 1.05 1.69 S P <![CDATA[K2O]]> <![CDATA[Na2O]]> MnO <![CDATA[TiO2]]> 0.176 0.01 0.127 0.066 0.445 0.215 <![CDATA[V2O5]]> Cu Zn <![CDATA[Cr2O3]]> NiO / 0.031 0.006 0.16 0.015 0.007 /

[0036] Table 2 Zinc phase analysis results of zinc-containing magnetite concentrate

[0037] Zinc phase name Zinc content Distribution rate Zinc in zinc sulfide 0.09 52.94 Zinc in zinc oxide 0.01 5.88 Other forms of zinc 0.07 41.18 total 0.17 100.00

[0038] Depend on Figure 1 The ore dressing process flow chart of an embodiment of the iron-zinc separation and enrichment ore dressing method of the zinc-containing magnetite concentrate of the present invention is shown in FIG. Figure 2 As shown in the full process number and mass flow chart of an embodiment of an iron-zinc separation, enrichment and beneficiation method for a zinc-containing magnetite concentrate of the present invention, the iron-zinc separation, enrichment and beneficiation method for a zinc-containing magnetite concentrate of the present invention is implemented by the following processes and steps:

[0039] (1) Zinc-sulfur mixed flotation of zinc-containing magnetite concentrate

[0040] Firstly, zinc-sulfur mixed flotation is carried out on the zinc-containing magnetite concentrate to obtain magnetite concentrate with Zn content less than 0.08% and zinc-sulfur mixed concentrate containing about 3.0% zinc.

[0041] In step (1), flotation is carried out by primary roughing; copper sulfate is used as an activator, BK606, BK608 and butyl xanthate are used as collectors, and 2# oil is used as a frother.

[0042] The dosage of the flotation reagents in step (1) is as follows: based on the amount of dry ore fed to the flotation ore, the dosage of the reagents is as follows: 200 g / t of copper sulfate for mixed flotation roughing, 150 g / t of BK606, 150 g / t of BK608, 50 g / t of butyric acid, and 50 g / t of frother 2# oil.

[0043] (2) Grinding of zinc-sulfur mixed concentrate

[0044] The step (2) uses a laboratory Φ240×90 conical ball mill for grinding, and the grinding particle size is -0.076mm 95%;

[0045] (3) Zinc-sulfur mixed concentrate grinding product zinc-sulfur separation flotation

[0046] The zinc-sulfur mixed concentrate grinding product with a Zn content of about 3.0% is subjected to zinc-sulfur separation to obtain a zinc concentrate with a Zn content of about 40% and a zinc tailings containing about 0.5% zinc (entering the iron concentrate).

[0047] The step (3) uses a mechanical stirring flotation machine, and the flotation operation adopts one roughing, four cleaning, and one scavenging. The middlings are returned in a "semi-concentrated-semi-sequential" manner, that is, the tailings of Concentrate 1 and the concentrate of Scavenging 1 are sequentially returned to the roughing, and the tailings of Concentrate 2, Concentrate 3, and Concentrate 4 are concentrated and returned to Concentrate 1. Lime is used as a pH adjuster and inhibitor; copper sulfate is used as an activator for zinc-containing minerals; and MK-306 is used as a collector.

[0048] The dosage of roughing reagents in step (3) flotation is: based on the dry ore amount of flotation feed, the dosage of reagents is: 4000g / t of lime, 600g / t of copper sulfate, and 120g / t of collector MK306.

[0049] The dosage of the flotation reagents in step (3) is as follows: based on the amount of dry ore fed to the flotation, the dosage of the reagents is as follows: 3000 g / t of lime and 50 g / t of copper sulfate for flotation 1; 1500 g / t of lime and 20 g / t of MK306 for flotation 2; 800 g / t of lime and 10 g / t of MK306 for flotation 3; 800 g / t of lime and 10 g / t of MK306 for flotation 4.

[0050] The dosage of scavenging agent in step (3) flotation is: based on the amount of dry ore fed to the flotation, the dosage of the agent is: 60g / t of MK306 for scavenging.

[0051] The results of experimental research show that, under the condition that the iron concentrate contains only 0.16% zinc, the present invention obtains a zinc concentrate product with a zinc grade greater than 40.0%, with an enrichment ratio of up to 250 times, and minimizes the loss of iron concentrate yield, with the loss of iron concentrate yield being only 0.17%. This solves the contradiction between the reduction of zinc in iron concentrate and the loss of iron concentrate yield to the greatest extent, and achieves an unexpected technical effect.

Claims

1. A method for separating and enriching zinc from zinc-containing magnetite concentrate, which is used to separate and enrich zinc from zinc-containing iron concentrate with a TFe grade of 65% to 67% and a Zn content of 0.10% to 0.20%, characterized in that The following process is used: S1 zinc-sulfur mixed flotation of zinc-containing magnetite concentrate Firstly, zinc-sulfur mixed flotation is performed on the zinc-containing magnetite concentrate to obtain a magnetite concentrate with a Zn content of less than 0.08% and a zinc-sulfur mixed concentrate containing 2.7% to 3.3% zinc; the zinc-sulfur mixed flotation adopts a primary roughing, copper sulfate is used as an activator, a mixture of BK606, BK608 and butyl xanthate is used as a collector, and 2# oil is used as a frother; S2 zinc-sulfur mixed concentrate grinding The zinc-sulfur mixed concentrate obtained in step S1 is fed into the grinding operation, and the particle size of the grinding product is controlled at -0.076 mm, with the mass accounting for 91% to 97%; S3 zinc-sulfur mixed concentrate grinding product zinc-sulfur separation flotation The zinc-sulfur mixed concentrate grinding product discharged from step S2 is fed into zinc-sulfur separation flotation operation to obtain zinc concentrate with Zn content ≥40% and zinc tailings with zinc content ≤0.55%. The zinc tailings are combined with the magnetite concentrate from step S1 to form a final iron concentrate with zinc content ≤0.095%. The zinc-sulfur separation flotation operation adopts 1 roughing selection, 1 scavenging selection and 3 to 5 cleaning selections, lime is used as pH adjuster and inhibitor, copper sulfate is used as zinc-containing mineral activator, and MK-306 is used as collector.

2. The iron-zinc separation, enrichment and beneficiation method of a zinc-containing magnetite concentrate according to claim 1, characterized in that: In step S1, according to the amount of dry ore fed to the flotation ore, the dosage of reagents is: 100-300 g / t of copper sulfate, 100-200 g / t of BK606, 100-200 g / t of BK608, 25-75 g / t of butyric acid, and 40-60 g / t of frother 2# oil.

3. The method for separating, enriching and beneficiating iron and zinc from a zinc-containing magnetite concentrate according to claim 2, characterized in that: In step S1, the mass ratio of BK606, BK608 and butyrrolidone is (2.5-3.5):(2.5-3.5):

1.

4. The method for separating, enriching and beneficiating iron and zinc from a zinc-containing magnetite concentrate according to claim 1, 2 or 3, characterized in that: In step S3, the zinc-sulfur separation flotation operation adopts 1 roughing, 1 scavenging and 4 concentrating operations, and the middlings are returned in a "semi-concentrated-semi-sequential" manner, that is, the concentrate 1 tailings and the scavenging 1 concentrate are sequentially returned to the roughing operation, and the concentrating 2 tailings, the concentrating 3 tailings and the concentrating 4 tailings are concentratedly returned to the concentrating 1 operation.

5. The method for separating, enriching and beneficiating iron and zinc from a zinc-containing magnetite concentrate according to claim 4, characterized in that: In step S3, lime is used as pH adjuster and inhibitor, copper sulfate is used as zinc-containing mineral activator, and MK-306 is used as collector in flotation roughing operation; MK-306 is used as collector in flotation sweeping operation; lime is used as pH adjuster and inhibitor, and copper sulfate is used as zinc-containing mineral activator in concentration 1 operation; lime is used as pH adjuster and inhibitor, and MK-306 is used as collector in concentration 2 operation, concentration 3 operation, and concentration 4 operation.

6. The method for separating, enriching and beneficiating iron and zinc from a zinc-containing magnetite concentrate according to claim 5, characterized in that: In step S3, according to the amount of dry ore fed to the flotation, the dosage of flotation roughing agents is: 3500-4500 g / t of lime, 500-700 g / t of copper sulfate, and 100-150 g / t of collector MK306; the dosage of flotation scavenging agents is: 50-70 g / t of MK306.

7. The method for separating, enriching and beneficiating iron and zinc from a zinc-containing magnetite concentrate according to claim 6, characterized in that: In step S3, according to the amount of dry ore fed to flotation, the amount of lime used in the selection operation 1 is 2000-4000 g / t, and the amount of copper sulfate is 40-60 g / t; the amount of lime used in the selection operation 2 is 1200-1800 g / t, and the amount of MK306 is 15-25 g / t; the amount of lime used in the selection operation 3 is 700-900 g / t, and the amount of MK306 is 5-15 g / t; the amount of lime used in the selection operation 4 is 700-900 g / t, and the amount of MK306 is 5-15 g / t.

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