RU2683526C1 - Lumpy raw material disintegration method - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to the materials fine grinding, mixing, horizontal and vertical transportation and mechanical activation. Performing the lumpy raw materials supply to the grinding chamber limited space, inside which two vertically parallel disks are located, on which facing each other planes the destructive elements, the beaters, are radially fixed with gaps relative to each other. Performing the raw material pieces destruction by the centrifugal acceleration imparting to its particles due to one of the disks rotation and their collision with the working chamber side wall and destructive elements, the beaters. Performing the disintegrated raw materials extraction from the side opening in the working chamber and from its bottom part. Additionally developing the pressure gradient in the gaps between the movable and fixed disks destructive elements, the beaters, rows by the high-speed air flow in the said gaps development, which forms vacuum at the loading opening input, and the overpressure in the working bodies discharge branch pipe. Facing each other movable and fixed disks surfaces are made in the form of facing each other with concave surfaces plates. Wherein the recess in the plates is made in the form of intersecting by the forming surfaces two truncated cones surfaces, first of which is made in the plates central part in the form of diverging at an angle of 60–66° truncated cone surface, and the recess second part surface is formed by the second diverging at an angle of 150–160° cone side surface part. At that, the first truncated cone larger base forms a circle lying at the said cones side surfaces intersection. Wherein made on the stationary disk in the region of the first cone small base, and rotating the movable disk drive axis loading opening is mechanically fixed to the rotating disk first truncated cone small base center. Radial ventilation flow in the gaps between the impact elements, the beaters, is initiated by the ventilation blades placing on the movable disk peripheral circumference, which during the movable disk rotation form the air flow. Disintegrated material from located in the grinding chamber end surface behind the ventilation blades discharge opening is directed to the cyclone battery through the pipeline.

EFFECT: enabling increase in the disintegrated raw material particles movement velocity inside the disintegrator and the grinding process intensification.

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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 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 of which are two vertically parallel disks vertically facing each other, on the planes of which are destructive, radially fixed with gaps relative to each other elements (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 with destructive elements (bills), removing the 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 initiating a high-speed air flow in the said gaps, forming a vacuum at the inlet 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 performed in the idea of plates facing each other with concave surfaces, and the recess in the plates is made in the form of surfaces of two truncated cones intersecting the forming surfaces, the first of which is made in the central part of the plates in the form of a truncated cone diverging at an angle of 60 ° -66 °, and the surface of the second part the recesses forms a part of the lateral surface of the second cone diverging at an angle of 150-160 °, while the large base of the first truncated cone forms a circle lying at the intersection of the lateral surfaces the radii of these cones, the loading hole being made on a fixed disk in the region of the small base of the first cone, and the axis of the drive rotating the movable disk is mechanically fixed to the center of the small base of the first truncated cone of the rotating disk, while the radial ventilation flow in the gaps between the impact elements (bills), create by placing ventilation blades on the surface of the peripheral circumference of the movable disk, forming a disintegrated air stream during rotation of the moving disk Therians from the discharge openings disposed in the end surface of the grinding chamber for ventilation blades, the pipeline is directed to a cyclone battery.

In FIG. 1 schematically shows a cross section of a disintegrator that implements the inventive method.

In FIG. 1. The following designations are introduced: 1 - a cylindrical 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 - ball bearing, 11 - grinding chamber covers, 12 - first truncated cone, 13 - second truncated cone.

The invention consists in the following. The source material through the loading hole 2 enters the working chamber 1, where it is sequentially crushed on concentrically mounted rows of pins 7 of the movable disk (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 to the center of the rotor 4. The source material through 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 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, the disintegrated particles are moved from the loading opening 2 to the discharge opening 3 occurs not only under the action of centrifugal and gravitational forces, as is realized in the prototype method, but also under the influence of the pressure gradient that arises between these holes. This happens as follows. The high rotor speed, with the beater installed 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. In the installation, the air enters in the axial direction, is pushed out in the radial direction. The air masses under the action of centrifugal forces move in a cylindrical housing 1. The whole process can be divided into several stages: when the movable disk 4 rotates, the air between the space of the blades 8 rushes to the edge of the rotor. As a result, a low pressure zone is formed in the center of the wheel, in the area of which a loading hole 2 is located. This leads to the absorption of air masses from the outside. In the center of the chamber, the air flows change direction from axial to radial, entering the compartments between the blades. Due to the rapid rotation, the air masses rush to the inner wall of the housing. Kinetic energy is partially converted into compression energy, and air velocity decreases - a volumetric air flow is collected inside the body and excess pressure is generated. The gaseous mass rushes to the discharge opening 3, enters the pipeline, and then into the working area.

The created air flow passes in the cavity between the concave surfaces of the movable and fixed disks (Fig. 1). The radial section of the cavity forms a configuration in the form of a Loval nozzle, truncated in the longitudinal direction, (a tapering-expanding nozzle) representing a channel narrowed in the middle. The proposed design, facing each other of the surfaces of the rotating and fixed disks 4 and 5, serves, similar to the Loval nozzle, to accelerate the gas flow passing through the cavity, and, under certain conditions, reaching speeds exceeding the speed of sound. The high-speed air flow 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 thrown out 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 feed opening 2, maintaining a constant cycle of mixing, grinding and pumping.

The angle of divergence of the first cone, which forms the concave surfaces of the surfaces of the disks 4 and 5, facing each other, is selected in the central part of the plates in the form of a surface of a truncated cone diverging at an angle of 60 ° –66 °, and the surface of the second part of the recess forms part of the side surface of the second diverging angle of 150-160 ° cone. The choice of the indicated range of diverging angles of intersecting cones is due to the fact that the radial section of the cavity between the surfaces of the disks 4 and 5 facing each other forms a contour of the longitudinal section of the Loval nozzle, the optimal angles of the converging and diverging cones of which lie in the range of 60-66 ° and 10, respectively -15 ° respectively. The desire to ensure the optimal design of the disintegrator and explains the choice of ranges of diverging angles of intersecting cones, forming a concave surface of the turned sides of the disks 4 and 5 above.

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 feed 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 and amounted to 513 mm. The disks were placed in a cylindrical grinding chamber 1. The surfaces of the movable 4 and the stationary 5 disks facing each other were made in the form of plates facing each other with concave surfaces. The deepening in the plates was performed in the form of surfaces of two truncated cones intersecting the forming surfaces, the first of which was performed in the central part of the plates in the form of a surface of a truncated cone 12 diverging at an angle of 60 ° (Fig. 1 shows an angle ϕ = 30 ° equal to half the angle of the diverging cone ) The surface of the second part of the recess, formed part of the side surface of the second cone 13 diverging at an angle of 160 ° (Fig. 1 shows the angle at the lower base of the cone (ϕ ₁ = 10 °), while the large base of the first truncated cone forms a circle lying at the intersection of the side surfaces of these cones. The loading hole was made on a fixed disk in the region of the small base of the first cone. The axis 9, rotating the movable drive disk, is mechanically fixed to the center of the small base of the first truncated rotation cone 4. Radial ventilation flow in the gaps between the shock elements (bills) was created by placing on the end of the movable disk ventilation blades, which, when the movable disk rotates, increase the pressure in the area of the discharge opening 3. Disintegrated material from the discharge opening located in the end surface grinding chambers behind the ventilation blades, they are sent through a pipeline to a cyclone battery.

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. Ventilation blades 8 were made at the end of the movable disk (rotor). Using the said blades, an air stream was created inside the grinding chamber, which, passing through the cavity formed by the facing surfaces of the stationary 5 and movable 4 disks, was accelerated to high speeds, capturing disintegrated particles raw materials intensively grinding and destroying them to small sizes.

When using the proposed method, a productivity of 2200 kg / h was achieved. The average dispersion of the ground fluorohydrite was 4 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 10 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 for the disintegration of lumpy raw materials, which includes supplying lumpy raw materials to a limited space of the grinding chamber, inside of which are two vertically parallel disks, on the planes facing each other, which are destructive elements - beats, breaking pieces of raw material by giving 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 disintegration extraction 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 - beats of the movable and fixed disks by creating a high-speed air flow in the said gaps, forming a vacuum at the inlet 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 made in the form of plates facing each other surfaces, and the recess in the plates is made in the form of surfaces of two truncated cones intersecting the forming surfaces, the first of which is made in the center of the plates in the form of a surface of a truncated cone diverging at an angle of 60-66 °, and the surface of the second part of the recess forms part of the side surface of the second diverging at an angle of 150-160 ° cone, while the larger base of the first truncated cone forms a circle lying at the intersection of the side surfaces of these cones, and loading The primary hole is made on a fixed disk in the region of the small base of the first cone, and the axis of the drive rotating the movable disk is mechanically fixed to the center of the small base of the first truncated cone of the rotating disk, while the radial ventilation flow in the gaps between the impact elements - beats is initiated by placing a peripheral circle on the surface the movable disk of the ventilation blades forming an air flow during the rotation of the movable disk and the disintegrated material from the discharge opening located in the end surface of the grinding chamber behind the ventilation blades, sent through the pipeline to the cyclone battery.

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