CN115970903B - Method for extracting zinc concentrate from high-alkaline gangue type zinc mixed ore - Google Patents

Abstract

The application provides a method for extracting zinc concentrate from high-alkalinity gangue type zinc mixed ore, and relates to the field of ore dressing. A method for extracting zinc concentrate from an overbased gangue type zinc blende, comprising: grinding the raw ore of the high-alkaline gangue type zinc mixed ore, and then adding sodium silicate, sodium hexametaphosphate, sodium hydroxide, sodium carbonate, sodium sulfide and dodecylamine for roughing to obtain rough concentrate and rough tailings; adding sodium silicate, sodium hexametaphosphate and dodecylamine into the rough concentrate for first concentration to obtain zinc concentrate and first concentration tailings, and returning the first concentration tailings to the rough concentration step; adding sodium sulfide and dodecylamine into the coarse tailings for second concentration to obtain second concentration middlings and second concentration tailings, returning the second concentration middlings to the rough concentration step, and treating the second concentration tailings as final tailings. The method solves the technical problem that the high-alkalinity gangue type zinc mixed ore cannot be effectively utilized for a long time, and lays a foundation for realizing clean and efficient utilization of non-traditional resources.

Description

Method for extracting zinc concentrate from high-alkaline gangue type zinc mixed ore

Technical Field

The application relates to the field of mineral separation, in particular to a method for extracting zinc concentrate from high-alkalinity gangue type zinc mixed ore.

Background

Zinc is the third largest nonferrous metal, and is widely used as an important raw material for anti-corrosion materials, energy materials and magnetic materials in the industries of vehicles, bridges, ships, buildings, energy sources and the like. The zinc compound is an important functional material and is applied to the high-tech fields of energy materials, magnetic materials and the like. At present, the total amount of zinc ore resources in China is about 1.1 hundred million tons, and three types of sulfide ores, oxidized ores and mixed ores are mainly used, wherein the sulfide ores are available resources in the traditional technology, and the oxidized ores and the mixed ores are difficult to utilize in the traditional technology. A significant number of zinc ore resources are oxidized monosulfide mixed ores, including typical mixed ores, as well as oxidized ores containing small amounts of sulfide minerals and sulfide ores containing small amounts of oxidized minerals. Recently, the modern metallurgical industry has developed and utilized zinc resources mainly including zinc sulfide (sphalerite and blende) for over 100 years. However, with the high-speed development of economy, the demand for nonferrous metal resources is increasing, the traditional and easily-handled zinc sulfide resources are decreasing, and the development requirement cannot be met. The zinc resource is prepared from complex oxidized ore and mixed ore with multiple metal and mineral phases, and the complex oxidized ore and the mixed ore cannot be separated and extracted efficiently by adopting the traditional dressing and smelting technology.

Therefore, research on synchronous sorting of multi-mineral-phase zinc resources is very important in practical significance.

Disclosure of Invention

The object of the present application is to provide a method for extracting zinc concentrate from an overbased gangue type zinc mixed ore, so as to solve the above problems.

In order to achieve the above purpose, the present application adopts the following technical scheme:

a method for extracting zinc concentrate from an overbased gangue type zinc blende, comprising:

grinding the raw ore of the high-alkaline gangue type zinc mixed ore, and then adding sodium silicate, sodium hexametaphosphate, sodium hydroxide, sodium carbonate, sodium sulfide and dodecylamine for roughing to obtain rough concentrate and rough tailings;

adding sodium silicate, sodium hexametaphosphate and dodecylamine into the rough concentrate for first concentration to obtain zinc concentrate and first concentration tailings, and returning the first concentration tailings to the rough concentration step;

and adding sodium sulfide and dodecylamine into the coarse tailings to perform second concentration to obtain second concentration middlings and second concentration tailings, wherein the second concentration middlings return to the rough concentration step, and the second concentration tailings are treated as final tailings.

Preferably, in the roughing, the water glass is 300-600g/t, the sodium hexametaphosphate is 20-60g/t, the sodium hydroxide is 1800-2200g/t, the sodium carbonate is 1900-2100g/t, the sodium sulfide is 7000-9000g/t, and the dodecyl amine is 200-400g/t.

Preferably, the roughing time is 4-6min.

Preferably, in the first refining, the water glass is used in an amount of 100-300g/t, sodium hexametaphosphate is used in an amount of 15-25g/t, and dodecyl amine is used in an amount of 10-30g/t.

Preferably, the first beneficiation bubble scraping time is 4-6 minutes.

Preferably, in the second refinement, the sodium sulphide is used in an amount of 1800-2200g/t and the dodecyl amine is used in an amount of 30-50g/t.

Preferably, the second beneficiation bubble scraping time is 4-6 minutes.

Preferably, the end point of the grinding is that the particles below 200 meshes account for 70-80%.

Preferably, the zinc in the high alkaline gangue type zinc mixed ore is present in calamine, sphalerite and calamine.

Preferably, the high alkaline gangue type zinc mixed ore further comprises iron minerals, lead minerals, copper minerals and gangue minerals.

Compared with the prior art, the beneficial effects of this application include:

the method for extracting zinc concentrate from the high-alkalinity gangue type zinc mixed ore provided by the application adopts sodium silicate and sodium hexametaphosphate to inhibit gangue ore, sodium hydroxide to adjust ore pulp, sodium carbonate to disperse ore pulp and activate target minerals, and adopts a thiamine method to activate and collect zinc minerals, thereby breaking through the traditional separation mode of 'firstly sulfur before oxygen', creatively providing a novel synchronous flotation method for multi-mineral phase minerals of the same metal, shortening and simplifying the flotation process, reducing the selectivity of medicament types, and adopting a closed-circuit process of 'one coarse and two fine', recycling zinc concentrate, and obtaining zinc concentrate with high grade and high recovery rate.

The method establishes a system for synchronously separating multi-mineral-phase zinc minerals, solves the technical problem that the high-alkaline gangue type zinc mixed ore cannot be effectively utilized for a long time, and lays a foundation for realizing clean and efficient utilization of non-traditional resources.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate certain embodiments of the present application and therefore should not be considered as limiting the scope of the present application.

FIG. 1 is a graph of the energy spectrum of an ore sample;

FIG. 2 is a schematic process flow diagram of the method provided in the example for extracting zinc concentrate from an overbased gangue type zinc mixed ore;

FIG. 3 is a graph showing the effect of dodecylamine usage;

FIG. 4 is a graph showing the effect of sodium sulfide;

FIG. 5 is a schematic illustration of the process flow provided in comparative example 1;

FIG. 6 is a schematic illustration of the process flow provided in comparative example 2;

fig. 7 is a schematic illustration of the process flow provided in comparative example 3.

Detailed Description

The term as used herein:

"prepared from … …" is synonymous with "comprising". The terms "comprising," "including," "having," "containing," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, step, method, article, or apparatus.

The conjunction "consisting of … …" excludes any unspecified element, step or component. If used in a claim, such phrase will cause the claim to be closed, such that it does not include materials other than those described, except for conventional impurities associated therewith. When the phrase "consisting of … …" appears in a clause of the claim body, rather than immediately following the subject, it is limited to only the elements described in that clause; other elements are not excluded from the stated claims as a whole.

When an equivalent, concentration, or other value or parameter is expressed as a range, preferred range, or a range bounded by a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when ranges of "1 to 5" are disclosed, the described ranges should be construed to include ranges of "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a numerical range is described herein, unless otherwise indicated, the range is intended to include its endpoints and all integers and fractions within the range.

In these examples, the parts and percentages are by mass unless otherwise indicated.

"parts by mass" means a basic unit of measurement showing the mass ratio of a plurality of components, and 1 part may be any unit mass, for example, 1g may be expressed, 2.689g may be expressed, and the like. If we say that the mass part of the a component is a part and the mass part of the B component is B part, the ratio a of the mass of the a component to the mass of the B component is represented as: b. alternatively, the mass of the A component is aK, and the mass of the B component is bK (K is an arbitrary number and represents a multiple factor). It is not misunderstood that the sum of the parts by mass of all the components is not limited to 100 parts, unlike the parts by mass.

"and/or" is used to indicate that one or both of the illustrated cases may occur, e.g., a and/or B include (a and B) and (a or B).

A method for extracting zinc concentrate from an overbased gangue type zinc blende, comprising:

grinding the raw ore of the high-alkaline gangue type zinc mixed ore, and then adding sodium silicate, sodium hexametaphosphate, sodium hydroxide, sodium carbonate, sodium sulfide and dodecylamine for roughing to obtain rough concentrate and rough tailings;

adding sodium silicate, sodium hexametaphosphate and dodecylamine into the rough concentrate for first concentration to obtain zinc concentrate and first concentration tailings, and returning the first concentration tailings to the rough concentration step;

and adding sodium sulfide and dodecylamine into the coarse tailings to perform second concentration to obtain second concentration middlings and second concentration tailings, wherein the second concentration middlings return to the rough concentration step, and the second concentration tailings are treated as final tailings.

In an alternative embodiment, in the roughing, the amount of water glass is 300-600g/t, sodium hexametaphosphate is 20-60g/t, sodium hydroxide is 1800-2200g/t, sodium carbonate is 1900-2100g/t, sodium sulfide is 7000-9000g/t, and ethylenediamine is 200-400g/t.

Alternatively, in the roughing, the amount of water glass may be 300g/t, 400g/t, 500g/t, 600g/t or any value between 300 and 600g/t, the amount of sodium hexametaphosphate may be 20g/t, 30g/t, 40g/t, 50g/t, 60g/t or any value between 20 and 60g/t, the amount of sodium hydroxide may be 1800g/t, 1900g/t, 2000g/t, 2100g/t, 2200g/t or any value between 1800 and 2200g/t, the amount of sodium carbonate may be 1900g/t, 2000g/t, 2100g/t or any value between 1900 and 2100g/t, the amount of sodium sulfide may be 7000g/t, 8000g/t, 9000g/t or any value between 7000 and 9000g/t, and the amount of dodecylamine may be 200g/t, 300g/t, 400g/t or any value between 200 and 400g/t.

In an alternative embodiment, the rougher time is 4-6 minutes.

Alternatively, the roughing time may be any value between 4min, 5min, 6min, or 4-6min.

In an alternative embodiment, in the first refinement, the water glass is used in an amount of 100 to 300g/t, sodium hexametaphosphate is used in an amount of 15 to 25g/t, and ethylenediamine is used in an amount of 10 to 30g/t.

Alternatively, in the first refinement, the water glass may be used in an amount of 100g/t, 200g/t, 300g/t, or any value between 100 and 300g/t, the sodium hexametaphosphate may be used in an amount of 15g/t, 20g/t, 25g/t, or any value between 15 and 25g/t, and the dodecylamine may be used in an amount of 10g/t, 20g/t, 30g/t, or any value between 10 and 30g/t.

In an alternative embodiment, the first beneficiation bubble scraping time is 4-6 minutes.

Alternatively, the first selected bubble scraping time may be any value between 4min, 5min, 6min, or 4-6min.

In an alternative embodiment, the second refinement uses sodium sulfide in an amount from 1800 to 2200g/t and ethylenediamine in an amount from 30 to 50g/t.

Alternatively, in the second refinement, the sodium sulfide may be used in an amount of 1800g/t, 1900g/t, 2000g/t, 2100g/t, 2200g/t, or any value between 1800 and 2200g/t, and the dodecylamine may be used in an amount of 30g/t, 40g/t, 50g/t, or any value between 30 and 50g/t.

In an alternative embodiment, the second beneficiation bubble scraping time is 4-6 minutes.

Alternatively, the second selected bubble scraping time may be any value between 4min, 5min, 6min, or 4-6min.

In an alternative embodiment, the endpoint of the milling is 70-80% of the particles below 200 mesh.

Optionally, the end point of the grinding is any value with the particle ratio below 200 meshes reaching 70%, 75%, 80% or 70-80%.

In an alternative embodiment, the zinc in the overbased gangue type zinc blendstock is present in calamine, sphalerite, and calamine.

In an alternative embodiment, the overbased gangue type zinc blendstock also includes iron minerals, lead minerals, copper minerals, and gangue minerals.

Embodiments of the present application will be described in detail below with reference to specific examples, but it will be understood by those skilled in the art that the following examples are only for illustration of the present application and should not be construed as limiting the scope of the present application. The specific conditions are not noted in the examples and are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or apparatus used were conventional products commercially available without the manufacturer's attention.

First, a raw ore processed in the present application will be described, specifically as follows: the zinc ore of a certain mine is selected for sampling and is subjected to ore technology research, and the ore sample mainly comprises Si, zn, ca, fe, S, C, pb, al, ba, K, mg, na, mn and other elements through energy spectrum analysis, as shown in figure 1. Other elements cannot be displayed due to low content of the energy spectrum analysis spectrogram. The specific components and the content are shown in table 1:

TABLE 1 raw ore composition table

Through electron microscope, energy spectrum, chemical phase and XRD analysis, the main zinc minerals in the ore sample are hydrozincite, sphalerite (including marblesite) and calamine; iron minerals such as pyrite, pyrrhotite, limonite, hematite, magnetite, etc.; lead minerals such as galena, white lead, and lead pyrolusite; trace copper minerals such as chalcopyrite and cuprite; gangue minerals mainly comprise quartz, calcite, barite, celestite, small or trace amount of mica (sericite, biotite, etc.), feldspar (potassium feldspar, albite, plagioclase, etc.), clay minerals, pyroxene, amphibole, chlorite, etc. The results are shown in Table 2 below.

TABLE 2 mineral composition of ore

According to analysis, the main zinc-containing minerals in the ore include hydrozincite, sphalerite and calamine, and a small amount or trace amount of limonite and lead pyrolusite contain trace amount of zinc.

Chemical phase results show that about half of the zinc in the sample is stored in zinc carbonate, wherein zinc in the zinc carbonate mainly refers to zinc in the siderite, and the zinc content is 4.05 percent and accounts for 49.09 percent of the total zinc; the zinc in sulfide mainly refers to zinc in sphalerite, and the content of the zinc is 3.31 percent, accounting for 40.12 percent of the total zinc; zinc in silicate mainly refers to zinc in calamine, and the zinc content is 0.69% and accounts for 8.36% of the total zinc; other zinc (mainly, limonite and other minerals contain zinc) 0.20 percent and account for 2.42 percent of the total zinc. The recovered zinc is mainly zinc in the siderite, sphalerite and calamine.

The distribution of zinc in the raw ore is shown in table 3:

TABLE 3 distribution of zinc in raw ore

From table 3 above, in the zinc distribution, the hydrozincite was 49.09%, the sphalerite was 40.12%, and the calamine was 8.36%.

Particle size analysis of the main zinc-containing minerals in the ore:

because most of the hydrozincite, sphalerite and calamine in the ore are produced in a net-shaped or knot-shaped structure, in a crushed ore sample of 2-0mm, the inside of mineral particles is porous, and the main zinc-bearing minerals in the ore, the hydrozincite, sphalerite and calamine are measured in a sample of 2-0mm by using BPMA (a BPMA technology mineral parameter automatic analyzer of Beijing mining and metallurgy institute). Unlike conventional drawing methods, the particle size of minerals in the present application is calculated by BPMA, the "center drawing" method, and the mineral content of each fraction is expressed by weight (area x specific gravity). The central line drawing method is to draw a line every 10 degrees by taking the geometric center of the mineral particles as an origin, draw 18 lines altogether, each line can cut one or more sections of 'sectional lines' on the mineral particles, each section of sectional line corresponds to a certain area, the method uses the 'sectional line' to represent the diameter length of the mineral particles, and uses the corresponding area to multiply the specific gravity of the mineral to represent the content of the mineral particles.

The specific results are shown in table 4 below:

TABLE 4 particle size distribution

Table 4 above shows that the average grain size of the target mineral is the largest of the wurtzite, followed by the sphalerite and the smallest of the calamine. The amounts of wurtzite, sphalerite and calamine were greater than 74 microns, 67.45%, 51.88% and 48.62%, respectively. Less than 0.010mm are 2.52%, 3.90% and 8.32%, respectively. The calamine is in medium grain embedded cloth, and the sphalerite and the calamine are in medium grain finer embedded cloth.

Although the amount of minerals of Table 4 below 0.010mm is not large, as the fineness of the grind increases, the amount of this fraction, including other fines, increases accordingly.

The mineralogical factors affecting zinc recovery were analyzed as follows:

about 49.09%, 40.12% and 8.63% of zinc in the ore accounts for 97.57% of the total zinc content of the ore in the siderite, sphalerite and heteroelectrode ores, and the recovered zinc is mainly zinc in the recovered siderite, sphalerite and heteroelectrode ores; the net-like and knot-like structures are the main output structures of the siderite, sphalerite and heteropolar. Most of the net cores of the net structures are granular quartz. The intergrowth boundary of quartz with the target mineral is mostly smoother and simpler. The hardness of quartz is about 7, while the hardness of calamine, sphalerite and calamine is between 5 and 3.5, with a large difference in hardness. These are all beneficial to grinding and dissociating the target minerals;

the average grain diameters of the chabazite, the sphalerite and the calamine are respectively 0.217mm, 0.117mm and 0.107mm. Amounts greater than 74 microns were 67.45%, 51.88% and 48.62%, respectively. Amounts less than 10 microns were 2.52%, 3.50% and 8.62%, respectively. The maximum grain size of the siderite is middle grain embedded, and the sphalerite and the heteropolar ore are relatively smaller and are middle grain finely embedded. The dissociation condition of the magnesite after grinding can be better than that of sphalerite and calamine;

a small amount of calamine or sphalerite is produced in a fine pulse shape or a fine particle dispersion shape, is not easy to be completely separated from the intergrowth mineral, and is unfavorable for producing zinc concentrate.

Based on the analysis, the process design and reagent screening are carried out, water glass and sodium hexametaphosphate are adopted to inhibit gangue ores, sodium hydroxide is adopted to adjust ore pulp, sodium carbonate is adopted to disperse ore pulp and activate target minerals, and a thiamine method is adopted to activate and collect zinc minerals.

Sodium silicate and sodium hexametaphosphate are gangue inhibitors (including gangue such as calcite, quartz, etc.); the sodium hydroxide is strong alkali, so that the pH value of ore pulp can be effectively regulated, and if lime is adopted, the consumption is large, so that the zinc mineral separation is not facilitated; the sodium carbonate can activate zinc minerals and can serve as an activating agent and a dispersing agent, so that the target minerals are easier to float.

Example 1

As shown in fig. 2, the embodiment provides a method for extracting zinc concentrate from high alkaline gangue type zinc mixed ore, which specifically comprises the following steps:

firstly, crushing and grinding raw ore until the raw ore accounts for 75% below 200 meshes, then adding sodium silicate and sodium hexametaphosphate to inhibit gangue minerals (including quartz and other gangue), wherein sodium hydroxide and sodium carbonate are used for floatation and adjustment of the pH value of ore pulp, sodium sulfide is used for vulcanizing and activating zinc minerals, and dodecylamine plays a role in collecting and foaming. Wherein the water glass dosage is 500g/t, the sodium hexametaphosphate dosage is 40g/t, the sodium hydroxide and sodium carbonate dosage are 2000g/t and 2000g/t respectively, the sodium sulfide and dodecylamine dosage are 8000g/t and 300g/t respectively, and the roughing time is controlled at 5 min.

Secondly, the coarse concentrate which is coarsely selected adopts water glass and hexa-partial inhibition gangue minerals as well, and then is directly collected by adopting dodecylamine (the first fine selection is called as fine 1), the dosage of the water glass, the hexa-partial and the dodecylamine is respectively 200g/t, 20g/t and 20g/t, the scraping time of the fine 1 is controlled to be 5min, and the concentrate which is floated and selected by the fine 1 is the final product, namely zinc concentrate.

The product of the tailing tank after the fine 1 is used as middling (which can be called middling 1 for short) and returned to the roughing for circulation; the product of the tailings tank after roughing is subjected to sulfuration activation by adopting sodium sulfide and dodecylamine, the link is called fine 2, the dosage of the sodium sulfide and the dodecylamine is 2000g/t and 40g/t respectively, the foam scraping time of the fine 2 is controlled to be 5 minutes as well, the foam scraping time of the fine 2 is the same as that of the fine 1, the product of the fine 2 (called as middle 2 for short) and the middle 1 are returned to roughing operation for circulation treatment, and the tailings of the fine 2 are the final tailings.

The results of the closed-loop test are shown in Table 5 below:

TABLE 5 closed circuit test results

Example 2

Firstly, crushing and grinding raw ore until the raw ore accounts for 70% below 200 meshes, then adding sodium silicate and sodium hexametaphosphate to inhibit gangue minerals (including quartz and other gangue), wherein sodium hydroxide and sodium carbonate are used for floatation and adjustment of the pH value of ore pulp, sodium sulfide is used for vulcanizing and activating zinc minerals, and dodecylamine plays a role in collecting and foaming. Wherein the water glass dosage is 300g/t, the sodium hexametaphosphate dosage is 30g/t, the sodium hydroxide and sodium carbonate dosage are 1800g/t and 1900g/t respectively, the sodium sulfide and the dodecylamine dosage are 7000g/t and 200g/t respectively, and the roughing time is controlled to be 4 min.

Secondly, the coarse concentrate which is coarsely selected adopts water glass and hexa-partial inhibition gangue minerals as well, and then is directly collected by adopting dodecylamine (the first fine selection is called as fine 1), the consumption of the water glass, the hexa-partial and the dodecylamine is respectively 100g/t, 15g/t and 10g/t, the scraping time of the fine 1 is controlled to be 4min, and the concentrate which is floated and selected by the fine 1 is the final product, namely zinc concentrate.

The product of the tailing tank after the fine 1 is used as middling (which can be called middling 1 for short) and returned to the roughing for circulation; the product of the tailings tank after roughing is subjected to sulfuration activation by adopting sodium sulfide and dodecylamine, the link is called concentrate 2, the dosage of the sodium sulfide and the dodecylamine is 1800g/t and 30g/t respectively, the foam scraping time of the concentrate 2 is controlled to be 4 minutes as well, the foam scraping time of the concentrate 2 is the same as that of the concentrate 1, the product of the concentrate 2 (called as the concentrate 2 for short) and the concentrate 1 are returned to roughing operation for circulation treatment, and the tailings of the concentrate 2 are the final tailings.

The results of the closed-loop test are shown in Table 6 below:

TABLE 6 closed circuit test results

Example 3

Firstly, crushing and grinding raw ore until the raw ore accounts for 80 percent below 200 meshes, then adding sodium silicate and sodium hexametaphosphate to inhibit gangue minerals (including quartz and other gangue), wherein sodium hydroxide and sodium carbonate are used for floatation and adjustment of the pH value of ore pulp, sodium sulfide is used for vulcanizing and activating zinc minerals, and dodecylamine plays a role in collecting and foaming. Wherein the water glass dosage is 600g/t, the sodium hexametaphosphate dosage is 60g/t, the sodium hydroxide and sodium carbonate dosage are 2200g/t and 2100g/t respectively, the sodium sulfide and dodecylamine dosage are 9000g/t and 400g/t respectively, and the roughing time is controlled at 6min.

Secondly, the coarse concentrate which is coarsely selected adopts water glass and hexa-partial inhibition gangue minerals as well, and then is directly collected by adopting dodecylamine (the first fine selection is called as fine 1), the dosage of the water glass, the hexa-partial and the dodecylamine is respectively 300g/t, 25g/t and 30g/t, the scraping time of the fine 1 is controlled to be 6min, and the concentrate which is floatingly selected by the fine 1 is the final product, namely zinc concentrate.

The product of the tailing tank after the fine 1 is used as middling (which can be called middling 1 for short) and returned to the roughing for circulation; the product of the tailings tank after roughing is subjected to sulfuration activation by adopting sodium sulfide and dodecylamine, the link is called concentrate 2, the dosage of the sodium sulfide and the dodecylamine is 2200g/t and 50g/t respectively, the foam scraping time of the concentrate 2 is controlled to be 6 minutes as well, the foam scraping time of the concentrate 2 is the same as that of the concentrate 1, the product of the concentrate 2 (called as the concentrate 2 for short) and the concentrate 1 are returned to roughing operation for circulation treatment, and the tailings of the concentrate 2 are the final tailings.

The results of the closed-loop test are shown in Table 7 below:

TABLE 7 closed circuit test results

To illustrate the effect of ethylenediamine and sodium sulfide on the methods provided herein, experiments were performed and the results are shown in fig. 3 and 4.

FIG. 3 shows that the amount of dodecanol has a significant effect on the zinc sulfide classification, and that dodecamine can be used to classify zinc sulfide. FIG. 4 shows that the amount of sodium sulfide has little effect on the floatability of sphalerite when the amount of sodium sulfide is greater than 2000 mg.L ^-1 The recovery rate of sphalerite was substantially stabilized at about 88.87%. Also interesting is that in the dodecylamine system, the excess sodium sulphide does not exert a strong inhibitory effect on sphalerite like in the xanthate system, which makes the combination of agents provided by the present application particularly advantageous.

Therefore, the amine sulfide method provided by the application can be used as an effective screening method for mixed zinc minerals.

Comparative example 1

The traditional xanthate is used as a reagent, and a sulfur-before-oxygen method is adopted for mineral separation, and a flow chart is shown in figure 5. The test results are shown in table 8 below:

table 8 test results

As can be seen from table 8, the zinc mineral index obtained by sulfur and oxygen is slightly worse than that obtained by synchronous flotation, but the zinc mineral index is quite different, and the process is complicated in the important point compared with that of synchronous flotation. Thus, the advantages of synchronous flotation are seen.

Comparative example 2

The comparative example focuses on the grinding fineness:

the grinding fineness test flow is shown in fig. 6.

The test data and results are shown in table 9 below:

table 9 test results

The grinding fineness test result shows that when the zinc ore accounts for 75% below 200 meshes, the recovery index of the zinc ore is the best, so that the grinding fineness is relatively important to the index of the process and is one of important investigation objects.

Comparative example 3

The gangue inhibitor sodium hexametaphosphate and water glass are not taken as important points for investigation, and the variable test is carried out on the regulator. The flow chart is shown in fig. 7.

Sodium sulfide variable tests were performed using a short open circuit procedure, the test results are shown in table 10 below:

table 10 test results

Therefore, in the open circuit process, the index of the sodium sulfide of 14 kg/t is good, and the sodium sulfide consumption can be obtained to obtain a good index when the pH value of ore pulp is regulated to be 12 or above.

The method provided by the application mainly carries out the following considerations and has the following advantages:

(1) because most zinc minerals in the zinc-bearing ores are concentrated in the siderite, sphalerite and calamine and have relatively high proportion, in order to simplify the existing process (the separate process of zinc oxide ore and zinc sulfide ore), three zinc-bearing minerals are jointly selected by adopting a synchronous floatation method. Thereby making the following process flow: three zinc-containing minerals are jointly selected to be used as target zinc concentrate.

(2) Because the hardness difference between the zinc-containing mineral and the gangue mineral (quartz) is large (about 2 differences), the grinding dissociation is in a favorable condition for separating the target mineral from the gangue mineral, and the grinding fineness is always controlled below 200 meshes to occupy 70-80% as a proper separation condition in the metal ore separation process.

(3) Since the average particle size of the three zinc-containing minerals is relatively large, the particle size of the siderite is the largest, and for the grinding operation, the particle size of the siderite is large in the ore grinding process, so that the particle size of the ore is below 200 meshes as a whole, the siderite and the heteropolar ore can be overground in the ore grinding process, and the siderite can be under a better dissociation condition. Therefore, the dissociation condition of the magnesite after grinding can be better than that of sphalerite and calamine.

(4) Because a small amount of calamine and sphalerite are produced in a fine pulse shape or a fine particle dispersion shape and are not easy to be completely separated from the intergrowth mineral, two inhibitors (sodium silicate and sodium hexametaphosphate) are used in the process flow to reduce the influence, so that the intergrowth gangue mineral is inhibited, and the grade of a zinc concentrate product is increased.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Furthermore, those skilled in the art will appreciate that while some embodiments herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the present application and form different embodiments. For example, in the claims below, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is only for enhancement of understanding of the general background of the application and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Claims (2)

1. A method for extracting zinc concentrate from high alkaline gangue type zinc mixed ore, which is characterized by comprising the following steps:

grinding the raw ore of the high-alkaline gangue type zinc mixed ore, and then adding a reagent consisting of sodium silicate, sodium hexametaphosphate, sodium hydroxide, sodium carbonate, sodium sulfide and dodecylamine for roughing to obtain rough concentrate and rough tailings;

adding a reagent consisting of sodium silicate, sodium hexametaphosphate and dodecylamine into the rough concentrate for first concentration to obtain zinc concentrate and first concentration tailings, and returning the first concentration tailings to the rough concentration step; in the raw ore, the zinc content in the siderite is 4.05 percent, which accounts for 49.09 percent of the total zinc content; the zinc content in the sphalerite is 3.31 percent, accounting for 40.12 percent of the total zinc content; the zinc content in the calamine is 0.69 percent, accounting for 8.36 percent of the total zinc content;

adding a reagent consisting of sodium sulfide and dodecylamine into the coarse tailings to perform second concentration to obtain second concentration middlings and second concentration tailings, wherein the second concentration middlings return to the coarse concentration step, and the second concentration tailings are treated as final tailings;

in the roughing, the dosage of water glass is 300-600g/t, the dosage of sodium hexametaphosphate is 20-60g/t, the dosage of sodium hydroxide is 1800-2200g/t, the dosage of sodium carbonate is 1900-2100g/t, the dosage of sodium sulfide is 7000-9000g/t, and the dosage of dodecyl amine is 200-400g/t;

the roughing time is 4-6min;

in the first refining, the dosage of the water glass is 100-300g/t, the dosage of the sodium hexametaphosphate is 15-25g/t, and the dosage of the dodecyl amine is 10-30g/t;

the first carefully chosen foam scraping time is 4-6min;

in the second refining, the dosage of sodium sulfide is 1800-2200g/t, and the dosage of dodecyl amine is 30-50g/t;

the second carefully chosen foam scraping time is 4-6min;

the end point of the ore grinding is that the particles below 200 meshes account for 70-80 percent.

2. The method of claim 1, wherein the overbased gangue type zinc blend further comprises iron minerals, lead minerals, copper minerals, and gangue minerals.

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