RU2057600C1 - Method of metal particles extraction from natural material - Google Patents

Abstract

FIELD: solid materials separation and sorting. SUBSTANCE: method of metal particles extraction from natural material provides for initial material preliminary size screening, crushing of preliminary screened over latticed product with simultaneous rolling or pressing of metal particles to make them flat, repeated screening of crushing process products by sizing screen with size of screening holes equal to size of screening holes used for preliminary size screening. Flattened metal particles are removed as over latticed product for repeated size screening. EFFECT: increased productivity. 3 dwg, 2 tbl

Description

 The invention relates to the separation or sorting of solid materials, in particular to the separation of the constituents of the mixture according to physico-mechanical properties, namely to the extraction of metal particles from granular natural material.

 The invention can find application in mining, metallurgical and other industries when sorting mixtures for the allocation of metal particles.

 Known methods and devices for separation (screening) of the components of the mixture in density and shape ("Separator for separating heavy metal particles"), in which the material is initially sieved through an inclined sieve, and then the sifted material is washed, separating light particles from heavy .

 Also known is a method for sorting flat parts, in particular sheet stampings, which takes into account frictional properties or roughnesses on both surfaces of flat parts materials.

 In addition, there is a known crushing and screening method and device for extracting particles of a certain strength and particle size from granular natural material comprising two stages of screening and crushing of an oversize product of the first stage of screening, however, the specified method and device for its implementation does not use the plasticity of the material (metal) to extract it.

 Closest to the technical nature of the present invention is a method for extracting metal particles from a natural material comprising two stages of screening of the source material with intermediate crushing and removal of metal particles.

 However, in the known methods and devices described above, it is impossible to perform better separation of metal, for example, gold, flat particles, which fail due to their small size, since none of the methods and the device provides selective separation of metal particles during the associated grinding of slags (waste rock) in order to remove the latter, which can be achieved only by changing the shape of small particles of metal and slag, and not just by screening them.

 The basis of the invention is the creation of a method for extracting metal particles from granular natural material, which would carry out additional processing of waste rock and slag particles, changing the metal particles in shape, i.e. flattening them and increasing their linear dimensions, ensuring the release of concentrate, thereby contributing to a more efficient extraction of metal particles from natural material or from the tailings of natural material.

 The problem is solved in that in the method for extracting flat metal particles from granular natural material, which consists in the fact that the natural material is subjected to at least two stages of screening, crushing the sack fraction of the first stage of screening and removing metal particles, according to the invention, simultaneously crushing the sieve product carry out rolling or pressing of metal particles to simplify them, and re-screening is carried out on a screen with the size of the sifting holes, p the same size of the screening holes of the screen for preliminary screening, while the flattened metal particles are discharged in the form of an oversize re-screening product.

 It is advisable to perform a crushing unit in the device for implementing the method in the form of two rolls mounted for rotation, one of which would be kinematically connected to the electric drive motor, and the side surface of the other roll would touch the side surface of the first roll.

 The proposed method for the extraction of metal particles from granular natural material, can improve the efficiency of the process of extracting metal particles, mainly flat, for example, gold, due to the fact that during additional processing, i.e. crushing in the form of rolling or pressing particles of classified material, metal particles of any shape are flattened and their linear dimensions are increased, and gangue particles are crushed.

 The proposed method meets environmental requirements, since chemical processes are not involved in their implementation and cyanidation, amalgamation, flotation processes harmful to natural resources and human health are excluded.

 Dust pollution, to some extent associated with the operation of the device, is much less dangerous to nature and public health.

 In FIG. 1 is a functional diagram of a method for extracting flat metal particles from bulk natural material by a rolling process; figure 2 is another functional diagram of the method in which the crushing of the classified material is carried out by pressing; in FIG. 3 is a schematic diagram of a device for implementing the method (longitudinal section), in the rolling process in which the crushing unit is made in the form of two rolls.

 To describe the proposed method for the extraction of flat metal particles from granular natural material, we turn to the functional diagram in figure 1.

Natural bulk material (e.g. pyrite) is first screened (first step) by placing (arrow a) it on a sieve 1 with rectangular, for example, square cells. Screening is carried out under the influence of vibration, as a result of which part of the initial product passes through the sieve 1 cells, the particle sizes of which are smaller than the sieve 1 mesh sizes. Thus (arrow b ₁ ) the first part of the under-sieve product is formed, which possibly contains grains of metal. (Further processing of this product is not the subject of the invention). After the first stage of screening, the natural bulk product (classified material) is fed to the metal table 2 via an inclined sieve 1 (arrow "c"), where additional processing is carried out, i.e. crushing of bulk material. In this case, crushing is carried out by rolling it, for example, using a roller 3 rotating around its own longitudinal axis d, moving along the table 2 in the forward and reverse directions (see arrow e).

As a result of rolling, the metal particles of the classified material change their shape, becoming flat, and the linear dimensions of the metal particles increase. Slag particles, also present in the mixture, are crushed as a result of rolling, turning into dust. After crushing, the mixture of crushed slag and flat metal particles is subjected to the second screening stage, for which it is moved (arrow f) to sieve 4, where the screening, as in the first stage, is carried out in the presence of vibration. After the second stage of screening, flat metal particles (concentrate) remain on the sieve 4, and small particles of crushed gangue remain in the sublattice product (b ₂ ). The resulting oversize (metal particles) and under-sieve (slag) products are separately removed from the working area (arrows g and b ₂ ).

 Figure 2 presents the scheme by which the second variant of the proposed method for the extraction of flat metal particles of natural material (ilmenite, garnet, pyrite) is carried out by the same processes as in the first embodiment described above. The difference lies in the fact that in this embodiment, crushing is carried out by pressing, for example, by means of a press 5, the upper plate 6 of which performs vertical impacts (movements) (arrow h). In this case, the metal particles change shape, i.e. flattened by crushing. Their linear dimensions, as in the case described above, increase, and the gangue particles are crushed, so that the metal particles (for example, gold) remain on sieve 4, and the gangue is poured into the sublattice.

 In FIG. 3 schematically depicts a variant of the device that implements the proposed method. The device comprises a receiving hopper in the form of a funnel 7 for placing natural material A attached to the wall of the housing 8 above the upper edge of the sieve 1, which serves as the first screening unit. The sieve 1 is installed with an inclination on the spring shock absorbers 9. The lower edge of the sieve 1 is placed above the intermediate guide funnel 10, the lower smaller opening of which faces the crushing unit in the form of two rolls 11, mounted for rotation on the axes mounted on the housing 8. One of the rolls 11 is kinematically connected with the electric motor 12. The rollers 11 are mounted on the axes 11 'so that their side surfaces touch each other (section p) to ensure counter rotation of the rollers 11. The narrow opening of the funnel 10 is located above the section p between the two rollers 11. The rollers 11 are touched by a clamping mechanism 13. Under the rolls 11, rubber cleaners 14 are installed to prevent contamination of the internal space of the device and, moreover, to perform a guiding function, i.e. transporting a mixture of metal flat particles and crushed slag into a passage hole 15, made in the inner partition 16 of the housing 8, for directing the mixture to a sieve 4, which functions as a second screening unit and installed with an inclination to the horizon on spring shock absorbers 17. Sieve 1 and 4 the first and second screening units are kinematically connected with vibration units 18.19, respectively. In the housing 8 of the device there are outlet openings 20, 21 and 22 for the release of the under-sieve product and flat metal particles, respectively. For more reliable transportation of the under-sieve product, screens 23,24,25,26 are placed under the screens 1 and 4, directing the under-sieve product into the outlet openings 20 and 21.

 A device that implements the method described above works as follows. The initial natural product, for example, pyrite with the flat metal particles contained therein, is loaded into a receiving hopper 7, from where it is poured onto a sieve 1 subjected to vibration. Through the sieve cells, 1 part of the initial natural product, including with metal grains, enters the sublattice and enters the outlet 20. Particles of a larger size, including metal particles of a flat shape (classified material), usually not passing through the sieve 1, along its inclined plane, they move into the intermediate guide funnel 10, from where they pass into the rolling unit, falling between the rollers 11, rotating towards each other. The first roll 11 is driven by an electric drive 12, entraining another roll 11. As a result, the metal particles contained in the classified product become flat, their linear dimensions increase, and the gangue particles are crushed. A mixture of flat metal particles and gangue particles through the through hole 15 falls on an inclined sieve 4, driven into a state of vibration by the action of the vibration unit 19. The crushed particles of waste rock fall through the sieve 4 cells into the sublattice and through the outlet 21 are removed from the device, and flat metal particles remain on the surface of the sieve 4 and enter through it into the outlet 22.

 Note that the cells of the sieve 4 are equal to the minimum size of the cells of the sieve 1.

 PRI me R 1. As a natural product was used the material of the tails of gravitational enrichment of one of the mines of Yakutia, delivered to the laboratory.

 At the first stage of screening, screening was carried out on a commercially available sieve in the class of 0.1 mm. Crushing of the resulting oversize product was carried out by rolling on a smooth metal steel sheet 2 (Fig. 1) with a roller 3, with a through channel made along the longitudinal axis, in which a metal rod was freely installed. Rolling was carried out manually.

 The second stage of screening was carried out on sieve 4, having a perforation of 0.1 mm and square cells. Vibration during screening was provided manually.

 As a result of the second stage of screening, the over-sieve product was a concentrate and consisted of flat gold particles, and the under-sieve product was crushed waste rock.

 For comparison, similar samples were processed on an F-2M flotation machine and on a SKL-2 concentration table. The results of the study are presented in table 1.

 PRI me R 2. Was used in the laboratory natural material in the form of tails of gravity (garnet, ilmenite), selected at one of the Kolyma mines.

 At the first stage of screening, screening was carried out according to the class of 0.5 mm on a sieve 1 (figure 3).

 Crushing, in this case rolling, of the classified material was carried out between the rollers 11. The resulting mixture of crushed gangue and flat gold particles was subjected to the second stage of screening on sieve 4 with square cells of the same size 0.5 mm.

 As a result, the material containing gold remained in the oversize product of the second screening stage (concentrate), and the empty material was crushed in the undersize product.

 For comparison, a similar sample was processed on a FM-2C flotation machine and on a SKL-2 concentration table.

 The research results are presented in table.2.

 From the above examples it follows that the enrichment of natural material, for example, sand of placer deposits, by the proposed method and implemented by the proposed device can significantly increase the extraction of gold and reduce the yield of concentrate, i.e. to obtain a concentrate with a higher content of precious metal, which means increasing the efficiency of the process of extracting metal from natural material.

Claims (1)

 METHOD FOR REMOVING METAL PARTICLES FROM NATURAL MATERIAL, including preliminary screening of the starting material, crushing of the oversize pre-screening product, re-screening of crushing products, removal of the under-screening product of re-screening and removal of metal particles, characterized in that simultaneously crushing and pre-crushing the products are grinded or pre-crushed metal particles to flatten them, and re-screening is carried out on a screen with p zmerom sieve openings equal to the size of sieve openings screening for pre-screening, and the flattened metal particles are withdrawn as product re-screening oversize.

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