“Ecomet Plus” LLC, Dnepropetrovsk, Ukraine:

Zubkov A. A., Chief Technologist, Candidate of Engineering Sciences, e-mail: trbusiness@mail.ru

This paper establishes the possibility of efficiency increasing of the processing of ores, which are difficult for concentration, due to the changes in the composition of the surface of oxidized minerals, by the transfer of oxides in the metallic state.

The transfer method of the oxidized surface of copper and bismuth minerals into the metallic surface directly in pulp is based on the usage of formaldehyde reducing agent in alkaline environment.

Alkaline environment (pH =12-12,5) was created by lime.

There were studied the operation conditions of the paraformaldegyde on the extraction of valuable components from the oxidized refractory silver ores: costs, PH-environment, temperature, “Solid : Liquid” ratio, processing time.

There was experimentally substantiated the metalization possibility of the oxidized surface of copper and bismuth minerals, silver and other metal oxides, which allowed to develop the high effective processing technology of oxidized copper, bismuth and silver-bearing ores in working environment.

In comparison with the traditional concentration methods, the silver extraction by recommended conditions is higher by 29%, extraction of lead and zinc is higher by 5,5 and 18,4 % respectively.

According to the technical and economic calculation, with the processing of 1 million tonnes of ore per year by the proposed technology, the amount of profit will be 1,9 million USD, at the expense of the additional products obtaining (silver, lead, zinc).

The proposed technology of ores concentration with the pre-metalization of oxidized surface of minerals allows to involve the oxidized and difficult for concentration ores into the processing sphere, without the environmental degradation.