RU2248248C1 - Method for flotation separation of sulfides - Google Patents

Abstract

FIELD: flotation concentration of non-iron metal sulfide ores.

SUBSTANCE: claimed method includes conditioning of sulfide-containing slurry in alkali medium with collector, foaming agent, and alkali metal dimethyldithiocarbamate. In foamed product one from sulfide is derived, and second or residual sulfides are derived in form of chamber product. Conditioning is carried out without aeration.

EFFECT: increased flotation selectivity.

3 ex, 3 tbl

Description

The invention relates to mineral processing and can be used in flotation concentration of non-ferrous sulfide ores.

A known method of flotation separation of pyrite-arsenopyrite products, including conditioning the pulp with sodium dimethyldithiocarbamate (DMDK), collector, blowing agent and subsequent flotation. The method allows to reduce the flotability of arsenopyrite to the level of its extraction with one blowing agent, while maintaining a high yield of pyrite [1].

The disadvantage of this method is the instability of the flotation process of the separation of sulfides associated with possible violations in the optimal ratio between the consumption of butyl xanthate and dimethyldithiocarbamate.

Closest to the proposed method is a flotation separation of lead-zinc concentrates, including pre-mixing in an alkaline medium of zinc sulfate and alkali metal dialkyl dithiocarbamate, conditioning the pulp with the mixture, introducing a collector, blowing agent and releasing lead minerals into the foam product and removing zinc minerals in the form of a chamber product [2]. The ratio of zinc sulfate, alkali metal dialkyl carbamate and soda is from 1: 0.75: 0.1 to 1: 1: 0.2. The method allows for the successful selection of lead-zinc collective concentrate.

The disadvantage of this method is not sufficiently high flotation indicators of the process of separation of sulfides - a decrease in the extraction of lead in lead concentrate compared with the cyanide process due to the depressing effect of DMDK on galena.

The objective of the invention is to obtain higher flotation in the separation of sulfides.

The technical result of the invention is an increase in the degree of selectivity of flotation during the separation of sulfides.

The technical result is achieved by the fact that in the method of flotation separation of sulphides, including conditioning pulp containing sulphides in an alkaline medium with a collector, blowing agent and dimethyldithiocarbamate of an alkali metal, the output of one of the sulphides into the foam product and the output of the second or other sulphides in the form of a chamber product, according to According to the invention, conditioning is carried out without aeration.

The research results showed that an increase in the degree of selectivity of flotation causes alkali metal dimethyldithiocarbamate, which is in the liquid phase in ionic form. Under aeration conditions, alkali metal dimethyldithiocarbamate is oxidized to form neutral thiuram disulfide molecules. The presence of thiuram disulfides in the pulp destabilizes the process of reducing the extraction of the second or remaining sulfides into the foam product. Aeration, i.e. Intensive mixing, accompanied by air suction, leads to the formation of thiuram disulfides and even to the precipitation of thiuram disulfides from the solution as an independent phase, which in turn has a profound violation of the influence of alkali metal dimethyldithiocarbamate on the flotation properties of sulfides during their flotation.

The method is as follows.

The pulp containing a mixture of sulfides, for example, pyrite, arsenopyrite and pyrrhotite, is conditioned in an alkaline medium with a collector - butyl xanthate, a blowing agent - MIBK (methyl isobutyl carbinol) and alkali metal dimethyldithiocarbamate without aeration. The absence of aeration is achieved by mixing with a magnetic stirrer at a low number of revolutions to prevent the formation of a funnel, which leads to air suction. As a result of flotation, sulfides are separated: one of the sulfides - pyrite is removed as a foam product, the other sulfides - arsenopyrite and pyrrhotite are removed as a chamber product.

Example 1

One gram of a mixture of sulfides containing pyrite, arsenopyrite and pyrrhotite is placed in a glass cup, pour 80 ml of distilled water, milk of lime is added until a pH of 10.5-11.0 is reached. The resulting pulp is transferred to the flotation chamber using the liquid phase from the beaker. Then, butyl xanthate is added to a concentration of 50 mg / L, stirred for 1 minute without aeration, after which freshly prepared alkali metal dimethyldithiocarbamate (DMDK) is added to the desired concentration, mixed again without aeration for 1 minute and MIBK blowing agent is added to a concentration of 50 mg / L. They float for 3 minutes. The results of the experiment are presented in table 1.

Table 1 Experience number CONCENTRATION DMDK, MG / L EXTRACTION,% Pyrites Arsenopyrite Pyrrhotite 1 about 90.50 53.06 42.38 2 10 20.71 23.62 3 thirty 8.21 21.01 4 fifty 84.23 7.86 19.70 5 100 87.27 7.42 12.92

As follows from the above results, the recovery of the remaining sulfides (arsenopyrite and pyrrhotite) is steadily decreasing.

Example 2

The experimental conditions are the same as in example 1, but alkali metal dimethyldithiocarbamate is introduced together with thiuram disulfides, which are in water-soluble form. The results of the experiment are presented in table 2.

table 2 EXPERIENCE NO. CONCENTRATION OF DMDK WITH THIURAMDISULFIDES, MG / L EXTRACTION,% Pyrites Arsenopyrite Pyrrhotite 1 about 90.50 53.06 42.38 2 10 22.04 28.54 3 thirty 12.21 20.61 4 fifty 85,10 13.90 23.86 5 100 85.13 21.12 17.90

As follows from the above results, the oxidation of part of DMDC to thiuram disulfides leads to a destabilization of the process of decreasing the yield of arsenopyrite.

Example 3

The experimental conditions are the same as in example 1, but the concentration of freshly prepared DMDK is constant and is 100 mg / L. The effect of the duration of mixing with aeration is investigated. The results of the experiment are presented in table 3.

Table 3 EXPERIENCE NO. AERATION TIME, min EXTRACTION,% Pyrites Arsenopyrite Pyrrhotite 1 0 82.71 4.88 21.11 2 1 85.41 0.82 26.96 3 3 88.05 74.45 29.43 4 5 85,10 40.37 54.34

As follows from the above results, the best data on the separation of pyrite from arsenopyrite and pyrrhotite were obtained with stirring without aeration (table 1, experiment 5). The recovery of pyrite in the foam product during aeration for 3 minutes (table 3, experiment 3) is 88.05%, but at the same time 74.45% of arsenopyrite and 29.43% of pyrrhotite are recovered in the foam product.

Thus, we can conclude that the present invention allows to obtain higher flotation rates during the separation of sulfides by increasing the degree of selectivity of flotation.

Sources of information used in the description:

1. Chanturia V.A., Nedosekina T.V., Fedorov A.A. About Flotation separation of pyrite-arsenopyrite products using low molecular weight organic reagents // Physicotechnical problems of mining, 1998, No. 5, pp. 99-105.

2. Copyright certificate of the USSR 1565526, cl. B 03 D 1/02, publ. 05/23/1990.

Claims (1)

Method of flotation separation of sulfides, including conditioning pulp containing sulfides in an alkaline medium with a collector, blowing agent and alkali metal dimethyldithiocarbamate, withdrawing one of the sulfides into the foam product and withdrawing the second or other sulfides in the form of a chamber product, characterized in that the conditioning is carried out without aeration .