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Beneficiation is a mechanical process of separating ore particles that
represent either a useful mineral or waste rock. To do this, use differences
in any differing properties of the useful mineral and waste rock: density,
wettability, color, gloss, hardness, optical,
electrical, magnetic, and other
properties.
Today there are many methods of ore beneficiation:
gravitational,
magnetic, electric, special. The flotation method, as the most versatile, is used
in the enrichment of sulfur, gold (processing of gold-bearing ores), coal
(enrichment of coal sludge), iron ores, and non-ferrous metal ores. Also,
flotation is used in tailings processing.
Flotation is a method of mineral processing in industrial plants. This
method is based on the ability of some particles - hydrophilic - to be easily wetted
with a liquid and separated from other particles - hydrophobic. The process
takes place in a liquid medium, which is aerated
with air or into which oil
droplets are introduced.
The separation of ore into elements occurs at the border of two different
means. In a flotation unit, hydrophobic particles adhere to gas or oil bubbles
and rise to the surface, while hydrophilic elements settle to the bottom of the
vessel. One part of the raw material goes into the foam product; the other part
of the raw material remains in the pulp. If minerals remain in the froth product,
flotation is called direct flotation. And if waste rock goes into the foam
product, the process is called reverse. In addition to water, other substances
can be used as flotation liquid.
There are four different flotation methods:
Oil. It is used for the extraction of sulfide minerals.
Minerals are
wetted with oil in the ore and float to the surface of the water, and waste rock
settles down.
Film. The principle of operation of this equipment is based on the
ability of small hydrophobic particles to adhere to the surface of the water.
Electro-flotation. Particles rise to the surface of the liquid due to the
release of electrolytic gases in the liquid.
Foam. In installations, small air bubbles are passed through the
mixture of ore in water, which float to the surface and are collected from it.
The work of both young and venerable scientists is devoted to the study
and improvement of the technology of enrichment
of various ores by the
flotation method. In particular, much attention is paid to this problem by the
staff of the Department of Processing and Processing of Mineral Resources
and Technogenic Raw Materials of the National Research Technological
University (or NRTU) ‘MIS&S’. A technique has been modeled for increasing
the quality of the concentrate by a factor of 2-3 for separate flotation of sands
and sludge in comparison with the standard scheme by capturing mineral