RU2668675C1 - Method for disintegration of lumpy raw material - Google Patents

Abstract

FIELD: disintegrators and crushing devices.SUBSTANCE: invention relates to a method for fine grinding and can be used for the processing of solid lumpy raw materials in the chemical, construction and other industries. Method consists in that, in the confined space of the grinding chamber, inside which two parallel disks are vertically disposed, a lumpy raw material is fed, which is destroyed by imparting to its particles a centrifugal acceleration due to the rotation of one of the disks and the collision of pieces of raw material with the side wall of the working chamber and destructive beater - elements radially fixed on the disks, and the disintegrated raw material is recovered. In this case, a pressure gradient is added in the gaps between the rows of beams, the surfaces of the movable and fixed discs facing each other are corrugated for this purpose, and the corrugations are performed in the form of Laval nozzles cut in the longitudinal direction, that are uniformly positioned radially along the surface of the discs, the tapered portions of the nozzles being positioned in the direction from the loading opening to the middle radial rows of beats, and the expanding parts of the nozzles are positioned from the middle radial rows to the discharge port located in the peripheral part of the discs. Also, to reinforce the venting effect that appears in the gaps on the end face of the movable disk, fix the ventilation blades, that are performed in the form of flat blades, rotated at an angle of 45 degrees with respect to the direction of movement of the disk. Then the disintegrated material from the discharge port is piped to the cyclone battery.EFFECT: method provides a reduction in the dispersion of the raw material particles by more than 2 times.1 cl, 3 dwg

Description

The invention relates to methods and devices for fine grinding, mixing, horizontal and vertical transportation, and mechanical activation of materials, including nanostructure, and can be used in chemical, construction and other industries, for the processing of solid lump raw materials, in particular waste chemical production, for example fluorohydrite, to the disintegration of lumpy rock mass, which contains particles of the useful component in a separate form, or in breed splices.

A known method of enrichment of raw materials with metal inclusions. The method includes feeding the feedstock into the space of the working chamber, which has a bottom part and a lid, exposure to destructive elements, distribution to components that contain and do not contain metal (I. M. Kelina "Ore dressing", M .: Nedra, 1979 , p. 93).

The disadvantage of this method is its low productivity due to the cyclical nature of the disintegration cycle. The method has limited use, since it allows you to separate the feedstock, which is characterized by low strength, or raw materials, which are represented by splices of strong and low strength components.

The method requires preliminary preparation of the feedstock, which negatively affects the cost of the final commercial product.

A known method of disintegration of lumpy raw materials, which is implemented in a method of enrichment of raw materials with metal inclusions.

The known method includes supplying lumpy raw materials to a limited space of the working chamber, exposing the raw materials to the bottom with destructive elements, disintegrating the raw materials and imparting centrifugal particles to the particles until they collide with the side wall of the working chamber and its cover, removing disintegrated raw materials from the side opening in the working chamber and from its bottom (Patent of Ukraine for the invention No. 64672).

The disadvantage of this method is that during the disintegration of raw materials, which consists of high-strength particles, the process of their destruction takes a long period of time.

The closest technical solution, selected as a prototype, is the method described in the patent (SU 1704821 A1, IPC B02C 13/22, publ. 15.01.1991). The disembrator that implements the prototype method comprises a housing, inside of which a rotor and a fixed disk with concentrically mounted rows of pins are vertically located, a loading and unloading pipe. In this case, the pins are distributed on a movable disk in a circle located closer to the center of the disk, and are made in cross section in the form of a rectangular shape. The remaining pins mounted on the movable disk are evenly distributed over concentric circles, remote from the central part of the disk made in the form of a trapezoidal shape with an angle of inclination of the working planes to the radial plane of 4-6 °. The pins located on the concentric circles of the fixed disk are made in the form of an isosceles trapezoid with concave lateral sides 9, the center of curvature of which is located above the smaller base at a distance equal to 0.6-0.8 of the height of the trapezoid, and the radius is 2.5-3.0 her heights.

The disintegration of raw materials in the prototype method is as follows. The source material through the loading pipe enters the working chamber, where it is sequentially crushed on concentrically mounted rows of rotor pins and fixed disk pins and is discharged through the discharge pipe. When the working surfaces of the pins of the rotor of the rotor of the disassembler are worn, they are reversed. The implementation of the pins of the specified shape and parameters provides a direct central impact with the particles of the crushed material without sliding and abrasion, which helps to increase the uniformity of the grinding product and the life of the pins. The ability of the dismantle to operate in reverse mode also significantly increases the service life. Direct impact leads to uniform wear of the working surfaces of the pins, which leaves the grinding quality unchanged throughout the life of the pins.

The disadvantage of this grinder is that according to the working hypothesis developed by I.A. Hint [Hint I.A. On the main problems of mechanical activation. Tallinn, 1977. Preprint 1.], activation is determined by three parameters: the speed of impact, the number of strokes and the time interval between subsequent strokes. Grinding elements with a round cross-section give the material the widest gamut of types of impact from direct impact to sliding with various angles of inclination, the activation of the material occurs over a wide range of forces from pure compression to shear forces, in the direct impact zone the material is activated by compression forces, and the product it is obtained predominantly of a large fraction, in the zone of a sliding impact, the material is activated by shear forces, and the product is obtained mainly of a small fraction. In the dismounter that implements the prototype method, there is no sliding and abrasion of particles of crushed raw materials, so it is impossible to achieve the maximum grinding fineness.

These disadvantages are due to the fact that there are no circulating flows in the working chamber that affect the displacement speed inside the grinding chamber of the raw material particle.

A significant duration of the processing of raw materials occurs due to the fact that the process of disintegration is significantly affected by the speed of collision of the particles of raw materials with destructive elements. In the prototype method, this speed is small, since the particles move along the gaps between the beams only under the influence of gravitational and centrifugal forces, which create insignificant dynamic forces and give individual particles relatively low acceleration in the direction from the loading hole to the discharge hole located in the peripheral part of the chamber grinding. The loss of particle velocity during movement requires a multi-cycle dynamic action to grind them to a given size.

When implementing the known method in a device for the disintegration of mineral raw materials, it is difficult to create excess pressure inside the working chamber, which complicates the conditions for the removal of crushed particles and creates conditions for the deposition of these particles inside the working chamber.

The technical problem to which the invention is directed is to increase the speed of movement of particles of disintegrated raw materials inside the disintegrator and to intensify the grinding process.

The solution to this problem is achieved by the fact that in the method of disintegrating lumpy raw materials, which includes supplying lumpy raw materials to a limited space of the grinding chamber, inside which there are vertically two parallel disks, on the planes facing each other, which destroy elements are radially fixed with gaps relative to each other ( beats), the destruction of pieces of raw materials by imparting centrifugal particles to its particles due to the rotation of one of the disks, and their collision with the side wall of the working chamber and destructive elements (bills), and the extraction of disintegrated raw materials from the side opening in the working chamber and from its bottom, additionally create a pressure gradient in the gaps between the rows of destructive elements (bills) of the movable and stationary disks by creating a high-speed air flow in the said gaps, creating rarefaction at the outlet of the loading hole and overpressure in the discharge pipe of the working bodies, for this, the surfaces of the movable and stationary disks facing each other are corrugated, and the corrugated We perform in the form of Loval nozzles cut in the longitudinal direction, which are uniformly located in the radial direction along the surface of the disks, while the tapering part of the nozzles is located in the direction from the loading hole to the middle radial rows of the beads, and the expanding parts of the nozzles are located from the middle radial rows of the beads to the unloading a hole located in the peripheral part of the disks, and to enhance the ventilation effect arising in the gaps, ventilation vanes are fixed at the end of the movable disk Which is in the form of flat blades, rotated at an angle of 45 degrees with respect to the direction of movement of the disc, disintegrated material from the discharge outlet of the conduit is directed to a cyclone battery.

In FIG. 1 schematically shows a cross section of a disintegrator that implements the inventive method. In FIG. 2. Schematically shows a radial view of the corrugations on a movable and fixed disk, made in the form of a truncated nozzle Loval.

In FIG. 3 shows a view and dimensions of an individual corrugation made in the form of a Loval nozzle truncated in the longitudinal direction.

In FIG. 1. The following designations are introduced: 1 - the body of the grinding chamber; 2 - loading hole; 3 - discharge hole; 4 - movable disk; 5 - fixed disk; 6 - working elements (bills) on a fixed disk; 7 working elements (bills) on a moving disk; 8 - ventilation blades; 9 - axis of the drive shaft; 10, 11 - ball bearing; 12 - loading pipe.

In FIG. 2. The following notation is introduced 2 - loading hole; 5 - fixed disk; 13 - corrugations made in the form of a Loval nozzle truncated in the longitudinal direction. Similar corrugations 13 are made on a movable disk (rotor).

In FIG. 3 the following designations are introduced: Z1, Z2, Z3 - sections in the boot of the corrugation; B1, B2, B3 - sections in the unloading part of the corrugation; O is the diameter of the critical section of the Loval nozzle. FIG. 1, FIG. 2, FIG. C serve to clarify the invention.

The invention consists in the following. The source material through the loading pipe 12 enters through the loading hole 2 into the working chamber 1, where it is subsequently crushed on concentrically mounted rows of pins 7 of the rotor 4 and pins 6 of the fixed disk (stator) 5 and is discharged out through the discharge pipe 3. The rotor 4 is driven by a drive, the axis of which 9 is mechanically connected through the ball bearing 10, 11 to the center of the rotor 4. The source material through the feed pipe 12 and the feed hole 2 falls on the first row of grinding elements (pins) 7, 6 of the stator 5 and rotor 4. As a result of an impact on these elements, the particles of material are destroyed and discarded to the following grinding elements of the stator, and so on, until the crushed material is completely released through the discharge pipe 3. In the inventive method, disintegrated particles are moved t the feed inlet 2 into the discharge opening 3 occurs not only under the influence of centrifugal and gravitational forces, as it is implemented in the prototype method, but also by the pressure gradient that occurs between said openings. This happens as follows. The high rotor speed, with the beaters installed and on it, with the help of ventilation blades 8 creates a stream of air moving from the loading hole 2 to the discharge hole 3. The created air stream passes through the corrugations 13 (Fig. 2), made in the form of a truncated the longitudinal direction of the Loval nozzle, (tapering-expanding nozzle) representing a channel narrowed in the middle. The Loval nozzle serves to accelerate the gas flow passing through it, under certain conditions, to speeds above the speed of sound. Since the corrugations 13 are made similar in shape and size not only in the stator, but also in the rotor, when the rotor rotates, when the corrugations overlap, they form a complete Loval nozzle. The high-speed air flow in the corrugations creates a strong vacuum inside the chamber, sucking in disintegrated particles and giving them high speeds, which significantly increases the intensity of disintegration and the degree of grinding (disintegration) of the raw material particles. The crushed material, reaching the last row of beats, is ejected at high speed through the discharge opening, and is sent through a pipeline to a cyclone battery. At the same time, fresh material is continuously sucked into the pipe 12, maintaining a constant cycle of mixing, grinding and pumping.

An example of a specific implementation. Using the proposed method, grinding of fluorohydrite was carried out, which from the storage hopper, with a metering screw, is dispensed in batches to grind the granules into a hammer mill (metering is carried out by calibrating and maintaining the required speed by the electric metering screw of the metering screw). After the hammer mill, fluorohydrite entered the disintegrator (Fig. 1) through the loading pipe 12 and the loading hole 2.

The disintegrator was made in the form of a movable (rotor) 4 and fixed 5 (stator) disks. The diameter of both disks was the same (Fig. 2) and amounted to 513 mm. Each of the disks had 6 corrugations 13 (Fig. 2) uniformly made in the disks in the radial direction. Each of the corrugations was a Loval nozzle truncated in the longitudinal direction. The dimensions of the cross sections of the corrugations and the bevel angles of the tapering and expanding parts of the nozzle are shown in FIG. 3.

On the movable and fixed disks on the surfaces facing each other, 6 and 5 rows of shock elements (beats) 7 and 6, respectively, were concentrically arranged. At the same time, a gap was formed between the rows of the movable and stationary disks, uniformly varying from 26 mm closer to the center to 14 mm at the most remote radii. At the end of the movable disk (rotor), ventilation blades were made in the form of plates 8 turned 45 ° to the direction of rotation of the disk. Using the above-mentioned plates, an air stream was created inside the grinding chamber, which, passing through corrugations made in the form of Loval nozzles, was accelerated to high speeds, capturing disintegrated particles of raw materials and crushing them intensively, destroying them to small sizes.

Using the proposed method, a productivity of 2000 kg / h was achieved. The average dispersion of ground fluorohydrite was 15 μm. When disintegrating fluorohydrite by the prototype method, the productivity did not exceed 1200 kg / h, and the average dispersion of crushed fluorohydrite did not decrease below 4 microns.

Thus, the claimed method compared with the method of the prototype allowed to increase 1.65 times, and the dispersion of the particles of raw materials to reduce more than 2 times.

Claims (1)

A method of disintegrating lumpy raw materials, which includes feeding lumpy raw materials to a limited space of the grinding chamber, inside of which there are vertically two parallel disks, on the planes facing each other, which are destructive elements radially fixed with gaps relative to each other - beats, breaking pieces of raw material by imparting it particles of centrifugal acceleration due to the rotation of one of the disks and their collision with the side wall of the working chamber and destructive elements - bills, and the extraction of disintegration of raw material from the side opening in the working chamber and from its bottom, characterized in that they additionally create a pressure gradient in the gaps between the rows of destructive elements - beat mobile and stationary disks - by creating a high-speed air flow in the said gaps, creating a vacuum at the outlet of the loading hole , and excess pressure in the discharge pipe of the working bodies, for this, the surfaces of the movable and stationary disks facing each other are corrugated, and the corrugations are made in the form of dissected into the home direction of the Laval nozzles, which are uniformly located in the radial direction on the surface of the disks, while the tapering parts of the nozzles are located in the direction from the loading hole to the middle radial rows of the beaters, and the expanding parts of the nozzles are located from the middle radial rows of the beaters to the discharge hole located in the peripheral part disks, and to enhance the ventilation effect arising in the gaps, ventilation blades are fixed on the end of the movable disk, which are made in the form of flat blades Attack, rotated at an angle of 45 degrees relative to the direction of movement of the disk, the disintegrated material from the discharge opening through the pipeline is sent to the cyclone battery.

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