RU2432999C2 - Method of flotation separation of collective lead-copper concentrate - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to dressing of minerals and may be used in flotation concentration of polymetallic ores and may be used in flotation concentration of polymetallic ores. Proposed method comprises conditioning of pulp containing copper and lead sulphides in alkaline limy medium with alkaline metal dichromate, extracting yellow copper ore into foam product and extracting galenite into flotation tail. Prior to conditioning with alkaline metal dichromate, additionally added is hydrogen peroxide in amount of 30-200 g/t, while alkaline metal dichromate is added in amount of 0.05-1.2 kg per ton of ore.

EFFECT: higher selectivity of flotation and lead extraction into lead concentrate, increased quality of lead and copper concentrates.

2 cl, 2 tbl, 2 ex

Description

The invention relates to the field of mineral processing and can be used in flotation processing of polymetallic ores in a selective flotation cycle of collective lead-copper concentrate for the separation of lead-copper concentrates.

Polymetallic ores are enriched according to developed technological schemes with the production of collective lead-copper concentrates and their subsequent separation by selective flotation.

A known method of flotation separation of a collective copper-lead concentrate, characterized in that in order to extract copper represented by chalcosine or bornite into a concentrate and reduce the cost of reagents, the flotation of a collective copper-lead concentrate is carried out in an alkaline medium using a sulfite mixture with galena as a depressant chrompike [USSR Author's Certificate No. 152439, cl. B03D 1/002, published in the Bulletin of Inventions No. 1 of 1963]. The ratio of components in the proposed mixture of reagents by weight: chrompick about 43%; sodium sulfite about 57%.

The disadvantage of this method is that the use of sulfite leads to suppression of flotation of sphalerite and the transition of sphalerite to lead concentrate. This requires the introduction of a de-galvanizing operation for lead concentrate. In addition, sulfoxide compounds can dissolve non-ferrous xanthates chemisorbed on the mineral surface, form complex and hardly soluble compounds that hydrophilize the surface of copper minerals, which leads to a disruption in the floatability of copper minerals and a decrease in copper recovery in copper concentrate. At pH above 5, the stability of lead thiosulfate complexes decreases, which leads to a violation of effective separation and a decrease in the degree of selectivity of flotation. The effectiveness of the method is reduced in the presence of secondary copper sulfides.

Closest to the proposed method is the separation of collective lead-copper concentrate, which includes conditioning pulp containing lead sulfides and copper in a neutral medium with alkali metal bichromate, withdrawing chalcopyrite into a foam product and removing galena into a chamber product [see Polkin S.I., Adamov E.V. "Enrichment of non-ferrous metal ores", Moscow, Nedra, 1983, p.123-128]. The method is effective if the lead contains enough lead in the copper-lead concentrate to produce a conditioned lead concentrate without refining, since after dichromate suppression the galena floatability is poorly restored. With this separation method, zinc minerals are suppressed and converted into lead concentrate, from where they can be extracted after activation with copper sulfate.

The disadvantage of this method is the insufficiently high flotation indices of the process of separation of lead and copper sulfides — a decrease in the extraction of lead into a lead concentrate compared with the cyanide method, due to the insufficient depressing effect of potassium dichromate on galena.

The objective of the invention is to obtain higher technological indicators of flotation in the separation of collective lead-copper concentrate.

The technical result of the invention is an increase in the degree of selectivity of flotation during the separation of collective lead-copper concentrate, increased recovery in lead concentrate, and the quality of lead and copper concentrates.

The technical result is achieved as follows. A flotation separation method for a collective lead-copper concentrate, including conditioning pulp containing lead and copper sulfides in an alkaline lime medium with alkali metal bichromate, discharging chalcopyrite into a foam product and withdrawing galena into a chamber product, characterized in that before conditioning with alkali metal bichromate additionally, hydrogen peroxide (30-200, g / t) is introduced, while alkali metal dichromate is introduced in an amount of 0.05-1.2 kg / t of ore; Flotation pH 9-11 is created by adding lime.

The research results showed that an increase in the degree of selectivity of flotation causes the combined action of modifiers - hydrogen peroxide and potassium dichromate in a calcareous medium.

The method is as follows. The pulp containing the collective lead-copper concentrate is conditioned in an alkaline environment created by lime, with hydrogen peroxide, alkali metal bichromate and flotation is carried out. As a result of selective flotation, sulfide minerals are separated:

copper sulfides are excreted as a foam product, galena is excreted as a chamber product.

Examples are carried out on a collective lead-copper concentrate obtained by processing polymetallic ore and containing 29% lead and 14% copper.

Example 1. A sample of collective lead-copper concentrate weighing 200 g was loaded into a mechanical flotation machine with a chamber volume of 0.5 l, conditioning was carried out only with potassium dichromate 90 g / t (basic version) or with hydrogen peroxide 180 g / t and potassium dichromate 65 g / t (the proposed option) and conducted copper flotation at pH = 9. A copper concentrate was obtained as a foam product, and a lead concentrate was obtained as a chamber product. Extraction of lead in lead concentrate amounted to 79.3% in the base case and 82.5% in the proposed embodiment. Analysis of the results of selective flotation showed that the best depression of flotation of galena was observed according to the proposed option. In this case, the recovery of lead in lead concentrate is 3.2% more compared to the base case.

Example 2. A portion of the collective lead-copper concentrate was floated in a closed cycle to obtain the finished lead and copper concentrates. Reagent consumption: hydrogen peroxide 30-70 g / t, potassium dichromate 740 g / t, pH = 10.5.

Basic version

The results of selective flotation of collective lead-copper concentrate in the base case are shown in table 1.

Table 1 The results of selective flotation of collective lead-copper concentrate in the base case Product Exit, % Content% Recovery% Cu Pb Cu Pb Pb-Cu Concentrate one hundred 13.76 29.30 one hundred one hundred Xi concentrate 57.29 22.68 7.36 94.4 14,4 Pb concentrate 42.71 1.79 58.73 5,6 85.6

The proposed method

The results of selective flotation of collective lead-copper concentrate by the proposed method are shown in table 2.

table 2 The results of selective flotation of collective lead-copper concentrate according to the proposed method Product Exit, % Content% Recovery% Cu Pb Cu Pb Pb-Cu Concentrate one hundred 13.84 29.42 one hundred one hundred Xi concentrate 57.11 22.78 6.33 94 12.3 Pb concentrate 42.89 1.94 60.17 6 87.7

As follows from the above results, the best data on the separation of collective lead-copper concentrate by selective flotation were obtained by the proposed method (table 2). The lead recovery in the lead concentrate is 87.7% with a lead content of 60.17% in the lead concentrate. Extraction of copper in copper concentrate is 94% with a copper content in copper concentrate of 22.78%.

The use of an improved flotation regime, the use of an additional depressant before feeding potassium dichromate in an alkaline calcareous medium made it possible to increase lead extraction in lead concentrate by 2.1% with a lead content of the same concentrate 60.17% (increased by 1.44%) and obtain a conditional copper concentrate with a copper content of 22.78% when extracting copper into copper concentrate 94%.

The combination of hydrogen peroxide with alkali metal bichromate in a calcareous environment creates the conditions for deep depression of galena (lead recovery to lead concentrate 87.7%) while the copper sulfide floatability is preserved (copper recovery to copper concentrate 94%).

The use of a combination of hydrogen peroxide and potassium dichromate in an alkaline rift can significantly improve the separation indicators of collective lead-copper concentrate.

Thus, we can conclude that the present invention allows to obtain higher technological parameters of flotation in the separation of collective lead-copper concentrate by increasing the degree of selectivity.

Sources of information used in the description

1. USSR copyright certificate No. 152439, cl. B03D 1/002, published in the Bulletin of Inventions No. 1 of 1963.

2. Polkin S.I., Adamov E.V. “Enrichment of non-ferrous metal ores”, Moscow. Nedra, 1983, p.123-128.

Claims (2)

1. A method of flotation separation of a collective lead-copper concentrate, including conditioning pulp containing lead sulfides and copper in an alkaline calcareous medium with alkali metal bichromate, discharging chalcopyrite into a foam product and withdrawing galena into a chamber product, characterized in that before conditioning with bichromate alkali metal is additionally introduced hydrogen peroxide in an amount of 30-200 g / t, while the alkali metal bichromate is driven in an amount of 0.05-1.2 kg / t of ore. 2. The method according to claim 1, which consists in the fact that the flotation pH is created by adding lime in an amount providing a pH of 9-11.