RU2555280C1 - Method of concentration of poor and balanced silver-containing sulphide ores and concentration tailings - Google Patents

Abstract

FIELD: mining.

SUBSTANCE: invention relates to concentration of sulphide silver-containing poor and balanced ores and concentration tailings, containing antimony silver sulphides. The method comprises grinding the starting material to a particle size of 95% mesh minus 0.071 mm. Then the ground material is activated with a mixture of copper sulphate and lead nitrate at their ratio of 1:1 to 1:2. After activation the flotation of silver sulphides is carried out with a mixture of potassium xanthate and potassium dialkyldithiophosphate at their ratio of 1:0.8 to 1:1.2.

EFFECT: increasing the extraction of silver in concentrate due to providing conditions contributing to the fullest exposure of silver-containing minerals.

2 tbl, 1 ex

Description

The invention relates to mineral processing and can be used in the extraction of silver from poor and off-balance ores, as well as tailings containing antimony silver sulfides.

The main reason for the loss of silver in the processing of poor and off-balance silver-containing ores and waste tailings from mining and processing polymetallic plants is the incomplete disclosure of useful minerals finely disseminated in the rock. Studies have shown that the carriers of silver in these objects are antimony sulfides (pyrargyrite, myargyrite, etc.), which have a thin intergrowth (up to 0.05 mm) and are closely associated with pyrite.

There is a method of processing old dumps of off-balance silver and antimony-containing ores and tailings based on the use of nuclear-physical (radiometric) sorting, separation and heap bacterial-chemical leaching using thionic bacteria (RF patent No. 2111060, IPC B03B 7/00, publ. 05/20/1998).

The disadvantages of this method include low efficiency, efficiency and environmental friendliness caused by the following circumstances:

- for any sort of sorting (radiometric, optical - by color, etc.), this method requires the allocation of the so-called "machine class", that is, screening of ore by size, and the presence of the so-called ore contrast according to some shared characteristic, whereas practice shows that such signs cannot always be distinguished;

- studies conducted under the conditions of the known method indicate that the heap bacterial-chemical leaching method is not suitable for antimony ores (thionic microorganisms die), the method has not yet been fully studied;

- the leaching method is relatively expensive compared to flotation;

- Using the heap leaching method can lead to infection of the aquatic environment with bacteria or antimony Sb 2 + / Sb 4+.

The closest analogue to the claimed invention is a method of beneficiation of silver sulfide ores and products, in accordance with which the initial product, crushed to a particle size of not more than 0.2 mm and a grade content of less than 0.074 mm 40-50%, enters the collective flotation of silver sulfides, which carried out in the presence of a collector of butyl xanthate (100 g / t), soda (2800-3200 g / t) and a blowing agent T-80, (70-90 g / t) with a ratio of 1: 28: 0.7 to 1: 32: 0.9 (description of the patent of the Russian Federation No. 2055645, IPC B03D 1/018, B03D1 / 02, publ. 03/10/1996).

However, experiments on the processing of poor and off-balance ores, as well as processing tailings containing antimony silver sulfides, carried out under the conditions of the known method, showed the impossibility of achieving high silver recovery in the resulting flotation concentrates.

The claimed invention is directed to the development of an effective method for processing poor and off-balance ores, as well as tailings, containing antimony silver sulfides, which provides a high-quality commercial product.

The technical result of the claimed invention is to increase the extraction of silver in a marketable product by providing conditions conducive to the most complete disclosure of silver-containing minerals.

The technical result noted above is achieved by creating a method for beneficiating poor and off-balance silver-containing sulfide ores and beneficiation tailings containing antimony silver sulfides by flotation of silver sulfides to produce silver concentrate in which the starting material is ground to a particle size of 95% of the class minus 0.071 mm, preliminary activation is carried out before flotation the crushed material with a mixture of copper sulfate and lead nitrate at a ratio of 1: 1 to 1: 2, and the subsequent flotation of silver sulfides is a mixture of x potassium anthogenate and potassium dialkyldithiophosphate with a ratio of 1: 0.8 to 1: 1.2.

The essence of the claimed invention is as follows.

As a result of the studies, it was found that the preliminary activation of the starting material, crushed to the declared size, with a mixture of copper sulfate and lead nitrate in the claimed ratio, followed by flotation of silver sulfides in the inventive reagent mode, allows to solve the problem of silver extraction from poor and off-balance ores containing antimony silver sulfides and tailings enrichment.

Experiments have shown that it is advisable to extract silver into a commodity concentrate by flotation enrichment of the starting material, crushed to a flotation size that ensures the disclosure of the surface of silver minerals and their effective flotation and is 95% class minus 0.071 mm (table 1).

It was found that before flotation the crushed material must be subjected to preliminary activation with a mixture of copper sulfate and lead nitrate in a weight ratio of 1: 1 to 1: 2. The inventive ratio of the components of the mixture was determined experimentally, based on obtaining optimal process indicators (table 1).

For the subsequent extraction of silver by experiment, a reagent flotation regime was established, which allows the most complete separation of silver into a concentrate. As the experiments showed, the highest technical and economic indicators are achieved by flotation extraction of silver using a mixture of potassium xanthate and potassium dialkyldithiophosphate with a weight ratio of 1: 0.8 to 1: 1.2 (table 1).

The following is an example confirming the possibility of implementing the claimed invention to obtain the above technical result.

Example

Tailings of ore dressing from the Taiga deposit with silver content of ~ 30 g / t, including those associated with myargyrite ~ 20 g / t, associated with pyrargyrite ~ 5 g / t, free silver ~ 5 g / t, were studied.

Table 1

The source material was crushed to a particle size of 95% class minus 0.071 mm with a supply of soda. The ground material was treated with a mixture of copper sulfate (100 g / t) and lead nitric acid (200 g / t) (1: 2 ratio), and the subsequent flotation of silver sulfides was carried out with a mixture of potassium xanthate (70 g / t) and potassium dialkyldithiophosphate (70 g / t) (1: 1 ratio). The silver content in the resulting crude concentrate was 583.1 g / t (silver recovery - 75.92%), while the silver content in the tails was only 7.72 g / t (table 1, experiment 7). The experiments also showed the effectiveness of one to three cleanings of the rough concentrate. It was found that three purifications of the rough concentrate make it possible to obtain a product containing 2382.7 g / t silver. A decrease in cleaning operations to two leads to a decrease in the silver content in the concentrate to 1600-1800 g / t without reducing its extraction.

The research results are shown in table 2.

As can be seen from the materials presented in table 1, only the totality of the claimed features provides the most efficient implementation of the silver extraction process with obtaining high quality concentrate (experiments No. 3, 5, 6, 7, 10 and 11). Exceeding the limits regulated by the claims led to unsatisfactory results (experiments No. 1, 2, 4, 8, 9, and 12).

Thus, the claimed invention successfully solves the problem of creating an effective method of beneficiation of poor and off-balance silver-containing sulfide ores and tailings containing antimony silver sulfides, which allows to achieve high rates of silver recovery.

Claims (1)

A method for beneficiating poor and off-balance silver-containing sulfide ores and dressing tailings containing antimony silver sulfides by flotation of silver sulfides to produce silver concentrate, while the starting material is ground to a particle size of 95% class minus 0.071 mm, prior to flotation, the ground material is pre-activated with a mixture of copper sulfate and lead nitrate at a ratio of 1: 1 to 1: 2, and the subsequent flotation of silver sulfides is carried out with a mixture of potassium xanthate and potassium dialkyldithiophosphate when they are enii from 1: 0.8 to 1: 1.2.