RU2821082C1 - Method for bulk flotation of polymetallic ores based on use of microemulsions - Google Patents

Abstract

FIELD: enrichment of minerals.

SUBSTANCE: proposed invention can be used in flotation of polymetallic lead-zinc, copper-nickel, copper-lead-zinc and other types of ores, which are processed according to collective-selective enrichment schemes. Method for collective flotation of polymetallic ores based on use of microemulsions includes a cycle of ore preparation by grinding with addition of sodium sulphide in amount of 100 g/t, reagent treatment of pulp with reagent-activator, which is copper sulphate, a collecting reagent based on potassium butyl xanthate in the form of a reverse microemulsion and a foaming agent T-92, which is a mixture of alcohols and dimethyldioxane ethers, and bulk flotation. Before the pulp is treated with the activating reagent, a pulp pH regulator is introduced to achieve values from 8.5 to 9.0. Before treatment with a collecting reagent based on butyl potassium xanthate in the form of a reverse microemulsion, a collecting reagent based on 5 dialkyldithiophosphates is additionally introduced into the pulp with the number of C atoms in the hydrocarbon chain from 2 to 5—BTP-152—with its share in the total consumption of collecting reagents from 15% to 85%.

EFFECT: increased selectivity of extraction of lead and zinc minerals into bulk concentrates of flotation, reduced weight fraction of iron in bulk sulphide concentrates.

1 cl, 2 tbl, 1 ex

Description

The invention relates to the beneficiation of minerals and can be used in the flotation of polymetallic lead-zinc, copper-nickel, copper-lead-zinc and other types of ores that are processed according to collective selective enrichment schemes.

There is a known method for flotation of non-ferrous metal ores [RF Patent No. 2379116, IPC B03D 1/00, B03D 1/02. publ. 01/20/2010], containing components such as copper, lead, zinc, and noble metals. The method includes grinding, conditioning, collective copper-lead flotation in a slightly alkaline environment with known reagents. In collective copper-lead flotation, a collector with the technical name “Beraflot” is used as a collector, which is a composition of dithiophosphates, thionocarbamates, C1-C4 aliphatic alcohols, a mixture of terpene alcohols and hydrocarbons, a mixture of propylene glycol butyl ethers, bottom residues from the production of butyl alcohols, 2 -ethylhexanol, 2-ethylhexanoic acid, ethylene propylene and ethylbenzene, followed by activation of sphalerite in a highly alkaline environment and flotation of zinc with a Beraflot collector from collective flotation tailings and production of waste tailings as a chamber product. The technical result of the claimed method is achieved based on the use of a composite collector due to the different affinities of the components with the surface of the separated minerals, which is determined by the energy characteristics of the atoms and the heterogeneity of the surface of the minerals and is manifested through the adsorption characteristics and adsorption kinetics of the components of the composite reagent.

The disadvantage of this method is the consumption of collecting reagents with various chemical properties for interaction with rock minerals and inevitable ions of the liquid phase of the pulp, which leads to a decrease in their sorption on ore minerals on the one hand and an increase in the flotation activity of the rock on the other. This circumstance leads to a decrease in flotation selectivity.

A known method for flotation of sulfide ores [RF Patent No. 2038857, IPC B03D 1/004, B03D 1/012, B03D 103/02. publ. 07/09/1995], which is based on the use of a flotation reagent composition containing butyl xanthate and sulfur-nitrogen oil concentrate obtained by two-stage extraction of its fraction with a boiling point of 200-300 ^o C with a solution of zinc chloride in dimethylformamide. Component ratio, mass: butyl xanthate 33-50, sulfur-nitrogen oil concentrate 50-67. The technical result is achieved by the presence of complex-forming functional groups associated with an apolar reagent, the sorption of which is higher on sulfide, partially hydrophobic minerals.

The disadvantage of this method is the instability of the composition and properties of the reagent; its production has not been established by the domestic industry.

The closest in technical essence seems to be a flotation method based on the use of emulsion forms of collector capable of protecting the collector from the action of inevitable ions of the liquid phase of the pulp and limiting its interaction with hydrophilic mineral grains [Application of reagents in the form of a reverse microemulsion for the flotation of lead and zinc sulfides / V. I. Bragin, N. F. Usmanova, E. A. Burdakova, A. A. Kondratieva // Russian Journal of Non-Ferrous Metals, 2022, Vol. 63, No. 5, pp. 482–489].

The method includes grinding sulfide lead-zinc ores to 65% class - 0.074 mm with the supply of lead and zinc mineral flotation activator sodium sulfide to the grinding at a consumption of 200 g/t, conditioning with a microemulsion of the reagent in an amount corresponding to the consumption of the main collecting reagent - butyl xanthate 25 g/t, as well as conditioning with T-92 foaming agent at a consumption of the latter 50 g/t.

The method is based on the selective delivery of an aqueous solution of an ionic sulfhydryl collecting reagent in the composition of an inverse microemulsion based on apolar substances as a dispersion medium for the flotation of metal sulfides. The selectivity of droplet fixation is determined by the hydrophobicity of mineral grains.

The disadvantage of this method is the dilution of non-ferrous metal concentrates with iron sulfide minerals due to the low selectivity of the butyl xanthate reagent towards them, which leads to low quality concentrates for the target metals.

The objective of the invention is to improve the quality of non-ferrous metal concentrates isolated from polymetallic ores by increasing the selectivity of the froth flotation process by selectively fixing a strong collecting reagent in the composition of microemulsions.

It is achieved in that in the method of collective flotation of polymetallic ores based on the use of microemulsions, including ore preparation, reagent treatment of the pulp with a collecting reagent based on xanthate in the form of a reverse microemulsion and a foaming agent, collective flotation, according to the invention, before the collective flotation, a collecting reagent based on dialkyldithiophosphates with the number of C atoms in the hydrocarbon chain from 2 to 5, with its share in the total consumption of collecting reagents from 15% to 85%, while a collecting reagent based on xanthates with a number of C atoms in the hydrocarbon chain from 2 is supplied as part of the microemulsion up to 5.

The method includes a cycle of ore preparation of the initial lead-zinc ore, reagent treatment of the pulp, collective flotation, as a result of which a collective concentrate is obtained, represented by sulfide minerals of lead and zinc, and flotation tailings.

The ore preparation cycle includes grinding the original ore to a size that ensures the opening of intergrowths of ore minerals, sphalerite and galena, and gangue minerals, with the simultaneous supply of sodium sulfide at a flow rate of 100 g/t.

During reagent processing of the pulp, sequential conditioning of the crushed ore is carried out with the following reagents:

1 pulp pH regulator to achieve values from 8.5 to 9.0;

2 sulfide surface activator, at a consumption of 200 g/t;

3 collecting reagent based on dialkyldithiophosphates with the number of C atoms in the hydrocarbon chain from 2 to 5 (BTF-152), with its share in the total consumption of collecting reagents from 15% to 85%;

4 reagent-collector based on xanthates with the number of C atoms in the hydrocarbon chain from 2 to 5, in the form of an inverse microemulsion.

Composition of the reverse microemulsion (in mass fractions), in accordance with the prototype: sodium sulfide - 0.1, casein - 0.2, kerosene - 61, 10% aqueous solution of butyl xanthate - 61, nonionic surfactant based on sorbitan monooleate ( SPAN-80) - 12.7. After feeding the reverse microemulsion, a foaming agent is introduced, which is a mixture of alcohols and dimethyldioxane ethers (T-92) at a consumption of 40 g/t.

Preliminary supply of a collecting reagent based on dialkyldithiophosphates with the number of C atoms in the hydrocarbon chain from 2 to 5 (BTF-152) before the introduction of a reagent based on xanthate with the number of C atoms in the hydrocarbon chain from 2 to 5, in the form of a reverse hydrophobizing microemulsion, promotes good fixation of its drops on hydrophobized areas of the mineral surface, formed due to the selective fixation of a reagent-collector based on dialkyldithiophosphates on sulfides of non-ferrous metals.

When microdroplets of the emulsion are fixed on the surface of partially hydrophobic sulfides, a concentrated solution of a reagent-collector based on xanthates interacts with the mineral surface under the protection of an oil film, which provides a greater coating density and a reduction in collector losses due to interaction with the surface of rock minerals and inevitable pulp ions.

Kerosene, which is part of the hydrophobizing microemulsion, acts as a dispersion medium. Stabilization of the microemulsion is achieved by introducing into its composition sodium sulfide, casein, and a nonionic surfactant based on sorbitan monooleate.

The introduction of a collecting reagent based on dialkyldithiophosphates with the number of C atoms in the hydrocarbon chain from 2 to 5, when its share in the total consumption together with a collecting reagent based on xanthates with the number of C atoms in the hydrocarbon chain from 2 to 5, does not lead to less than 15% a significant change in the content of valuable components in flotation products, flotation indicators. And, on the contrary, increasing its share above 85% does not make a significant difference compared to using only one collecting reagent based on dialkyldithiophosphate.

The use of collecting reagents based on dialkyldithiophosphates and based on xanthates with the number of C atoms in the hydrocarbon chain from 2 to 5 is due to the fact that a decrease in the length of the hydrocarbon radical entails a decrease in the collecting force and at the same time an increase in selectivity, thus, it is advisable to use it for various sulfide ores various radicals.

Preliminary supply of a collecting reagent based on dialkyldithiophosphates with the number of C atoms in the hydrocarbon chain from 2 to 5 (BTF-152) before the introduction of a reagent based on xanthate with the number of C atoms in the hydrocarbon chain from 2 to 5, in the form of a reverse hydrophobizing microemulsion, provides an increase selectivity of the froth flotation process.

The method of collective flotation of sulfide polymetallic ores makes it possible to increase the selectivity of the extraction of lead and zinc minerals into collective flotation concentrates, to reduce the mass fraction of iron in collective sulfide concentrates, which facilitates subsequent selection and production of qualified individual concentrates.

The present invention is illustrated by the following examples.

Example 1.

Collective flotation, according to the proposed method, is performed on lead-zinc ore of the Gorevskoye deposit, containing 2.92% Pb, 5.68% Zn., in accordance with example 2 of Table 1.

The ore preparation cycle includes grinding the original ore to a particle size of 80% class -0.074 mm in the presence of sodium sulfide at a consumption of 100 g/t. Crushed ore weighing 200 g was transferred to the chamber of an FML-1 (237FL) flotation machine with a chamber volume of 0.75 l, soda was dosed into the chamber to a pH of 8.5 to 9.0, and also conditioned with copper sulfate at a flow rate of 200 g/ T. Next, a collecting reagent based on dialkyldithiophosphates BTF-152 was additionally supplied, with its share in the total consumption of collecting reagents being 70%, followed by the introduction of a collecting reagent based on xanthates - potassium butyl xanthate in the form of an inverse microemulsion, with its share being 30 %. (example 2 table 1)

Examples of flotation performance depending on the proportion of collecting reagents in combination are given in Table 1.

Table 1 - Results of flotation of lead-zinc ore at various fractional ratios of collecting reagents

Example Share ratio
BTF-152/ BKK, % Consumption BTF-152/
BPC, g/t Product Exit, % Content, % Recovery, % Pb Zn Fe Pb Zn Fe 1 85/15 51 g/t/
9 g/t Collective
concentrate 28.87 7.45 6.14 24.18 73.67 31.22 27.86 Tails 71.13 1.08 5.49 25.42 26.33 68.78 72.14 Original 100.00 2.92 5.68 25.06 100.00 100.00 100.00 2 70/30 42 g/t /
18 g/t Collective
concentrate 28.96 8.05 6.48 25.03 79.82 33.04 28.93 Tails 71.04 0.83 5.35 25.07 20.18 66.96 71.07 Original 100.00 2.92 5.68 25.06 100.00 100.00 100.00 3 50/50 30 g/t /
30 g/t Collective
concentrate 30.21 7.79 6.40 25.83 80.59 34.02 31.14 Tails 69.79 0.81 5.37 24.73 19.41 65.98 68.86 Original 100.00 2.92 5.68 25.06 100.00 100.00 100.00 4 30/70 18 g/t /
42 g/t Collective
concentrate 33.27 7.15 5.95 26.25 81.46 34.83 34.86 Tails 66.73 0.81 5.55 24.46 18.54 65.17 65.14 Original 100.00 2.92 5.68 25.06 100.00 100.00 100.00 5 15/85 9 g/t /
51 g/t Collective
concentrate 34.37 6.95 6.00 26.58 81.75 36.33 36.46 Tails 65.63 0.81 5.51 24.26 18.25 63.67 63.54 Original 100.00 2.92 5.68 25.06 100.00 100.00 100.00

An increase in the proportion of potassium butyl xanthate leads to an increase in the iron content in the concentrate and a decrease in its quality. An increase in the proportion of BTF-152 leads to a decrease in the extraction of lead and zinc.

The total consumption of collectors was selected as 60 g/t based on preliminary tests and experience in the beneficiation of similar ores. The ratio of consumption of the collecting reagent potassium butyl xanthate (BX), supplied in the form of a microemulsion, and the collecting reagent based on BTF-152 dialkyldithiophosphates, in a fractional ratio of 70/ 30%, the highest content of lead and zinc in the collective concentrate is observed - 8.05% and 6.48%, respectively.

Thus, the reagent ratio of 70/30 ensures maximum selectivity of collective flotation.

Table 2 shows a comparative assessment of the results of flotation using collecting reagents based on xanthates in the form of a reverse microemulsion (example 2 of Table 1) and when supplying a collecting reagent in the form of solutions (example 6).

Table 2 - Examples of lead-zinc ore flotation with various forms of xanthatate-based reagent supply

Product Exit, % Content, % Recovery, % Pb Zn Fe Pb Zn Fe Example 2 table 1
Supply in the form of solutions: BTF-152 - 42 g/t and T-92 - 40 g/t.
Supply in the form of microemulsion: BKK - 18 g/t. Collective
concentrate 28.96 8.05 6.48 25.03 79.82 33.04 28.93 Tails 71.04 0.83 5.35 25.07 20.18 66.96 71.07 Original 100.00 2.92 5.68 25.06 100.00 100.00 100.00 Example 6
Supply in the form of solutions: BTF-152 - 42 g/t, BKK - 18 g/t, T-92 - 40 g/t Collective
concentrate 32.55 7.19 6.12 26.26 80.16 35.07 34.11 Tails 68.45 0.85 5.39 24.12 19.84 64.93 65.89 Original 100.00 2.92 5.68 25.06 100.00 100.00 100.00

The data in Table 2 show that the inventive flotation method with the supply of a collecting reagent based on xanthates in the form of an inverse microemulsion provides greater selectivity of enrichment compared to the generally accepted method of introducing collecting reagents in the form of solutions.

Claims (1)

A method of collective flotation of polymetallic ores based on the use of microemulsions, including a cycle of ore preparation by grinding with the addition of sodium sulfide in an amount of 100 g/t, reagent treatment of the pulp with an activator reagent, which is copper sulfate, a collecting reagent based on potassium butyl xanthate in the form reverse microemulsion and foaming agent T-92, which is a mixture of alcohols and dimethyldioxane ethers, collective flotation, characterized in that before treating the pulp with an activator reagent, a pulp pH regulator is introduced to achieve values from 8.5 to 9.0, and before treatment with the reagent - with a collector based on potassium butyl xanthate in the form of a reverse microemulsion, a collecting reagent based on 5 dialkyldithiophosphates with the number of C atoms in the hydrocarbon chain from 2 to 5 - BTF-152 - is additionally introduced into the pulp into the pulp, with its share in the total consumption of collecting reagents from 15% to 85%.