SU659186A1 - Method of classifying finely disintegrated material - Google Patents

Description

one

This invention relates to the field of mineral processing, in particular to methods for the classification of finely divided material.

Methods are known for classifying finely divided material prior to its enrichment, carried out on apparatus with a screening surface — curvilinear screens, drum screens rotating at supercritical speed, as well as hydraulic classifiers and hydrocyclones 1, 2.

However, the separation efficiency on hydraulic classifiers is about 75%, and on hydrocyclones - 50%. This significantly reduces the productivity of grinding equipment and clogs the concentrate with oversized material.

The classification process on hydrocyclones is inefficient, with low productivity, and hydrocyclones wear out quickly. The classifiers used in the classification process are large, heavy, and difficult to repair.

The closest to the described invention is the method of classifying finely divided material through a screening surface, and as

the latter use a flat vibrating screen 3.

However, the classification of the material on a flat vibrating screen is characterized by low (up to 33%) efficiency due to the large amount of electricity consumed by P1 and the rapid wear of the screening surface. The aim of the invention is to increase

specific proizptelposti process and improving the efficiency of classification due to the regeneration of the screening surface.

The goal is achieved by the fact that

in the classification of finely ground material through the screening surface, the last one is used for slop balls, which are affected by a nulling stream of water.

The dependence of the boundary diameter of separation on the diameter of the ball of the screening surface was experimentally established. With sufficient accuracy, this dependence is expressed

yr 0.16 yga

where drp is the boundary diameter of separation, mm;

dm is the diameter of the ball of the screening surface, mm. To classify fine material, a screening surface is used from a compacted layer of spherical bodies (balls) laid on a grate with a cell size of a slit of 1-2 mm or less on the diameter of the ball. The number of layers must be at least four. The method of classifying finely divided material through a screening surface is that pulp is fed to a layer of balls. At the same time, particles smaller than a specified boundary diameter (.р 0,16 diir) pass through the layer of balls, and particles larger than (t / rp 0) are transported to the surfaces of the screening layer from the balls (not passing through the layer). In this case, non-irons occur, cyclically cleaning the channels between the balls with a pulsating flow of water, i.e., the living section by sieving the surface of the network (regeneration). Thus, in the case of the Daina, there is a separation of particles of fineness, and the process does not depend on the physical properties of the original finely divided material (sludge). The results of classification are tabulated.

The path of movement of particles through the projectile surface of the layer of balls with this method is not perpendicular to the horizontal plane, but is a spatial line, the character of which reflects the structure of the balls in the screening surface (laying angle a 60-90 °).

The drawing shows the case of such a trajectory.

The size of the boundary diameter of the separation is equal to the cross section of the channel at the narrowest point (point C). The channel is a curvilinear triangle whose sides are represented by the surfaces of nearby balls.

Such a surface and the shape of these channels implies a high degree of probability that the grains of the boundary diameter fall below a predetermined size (from a layer of classified grains) into the channels, and in combination with the cyclic cleaning of the channels, the high efficiency of the process is absorbed.

The implementation of the described method at the Grushevskaya concentrator of the Marganets ore processing plant

provides an economic effect in the amount of 2.9 million rubles. in year.

Claims (3)

Invention Formula The method of classifying finely ground material through a sifting and surface, characterized in that, in order to increase the specific productivity of the process and increase the efficiency of classification due to regeneration of the sifting surface, layers of balls affected by a pulsating flow of water are used as the last. Information sources, taken into account during the examination 1. Andreev S. E. et al. Crushing, grinding and screening of minerals. M., "Nedra, 1961, p. 72-104. 2. Razumov K. А. Designing of processing plants. M., “Nedra, 1970, p. 514-518. 3. Andreev S. E. and others. Crushing, grinding and screening of minerals. M., "Nedra, 1961, p. 96