RU1777972C - Apparatus for separation of friable materials - Google Patents

Abstract

Usage: the device is intended for preparatory screening of bulk materials in the enrichment of minerals. SUMMARY OF THE INVENTION: intensification of the separation of bulk material in size in the zone of its free fall. Above the screening surface 4, a loading vibro-surface 3 is installed with holes 11 at its downstream end. The nozzle 5 is fixed in the guides 7 and is located between the vibro-surface 3 and the screening surface 4. The guides 7 are rigidly connected to the vibro-surface 3 and are made with curved grooves 8 for adjusting the position of the nozzle 5. By changing the height and angle of installation of the nozzle 5, you can adjust the boundary separation size . 1 s.p. f-ly, 5 ill. VJ S XJ S L 9W 1G 15 FIG. 4

Description

The invention relates to mineral processing, is intended for preparatory screening of bulk materials and can be used in the coal, mining, metallurgical, construction and chemical industries.

An air-string vibrating screen for classifying high moisture coals is known. It consists of a box with string sieves, a vibrator shaft, four suspensions, two axial fans, a feed chute, a diffuser, a casing, and a drive, consisting of an electric motor and a gearbox.

Coal of class 0-13 mm by gravity through the chute enters the chamber between the ° diffuser and the screen box, where the air flowing through the diffuser, the coal is pressed against the working part of the steeply inclined string sieve (45 °), while small grains (bayonet) are pressed through a sieve , larger grains glide over the working surface of this sieve and, together with the bayonet, which has not had time to pass through the working surface of the bit, enter the shallow part (15-25 °) of the string sieve for additional classification. The disadvantage of this device is the low screening efficiency due to the considerable resistance of the steeply inclined sieve during the passage of air through the openings, and the high resistance of the thick layer of material entering in one continuous stream. Under such screening conditions, small grains are not effectively squeezed out of the thick layer of material, and most of the grains displaced from the layer cannot fall through the holes of the steeply inclined sieve, since the main component of gravity is directed to transporting the material along the working surface. In addition, a stream of air is locally supplied to one section of the steeply inclined screen, which does not allow to achieve high Screening efficiency.

Known vibration screen GIST72, including a box mounted on supports, shock absorbers, an electric motor, a vibrator, two screens, spray devices. The disadvantage of this screening is the low screening efficiency, since the flow of the working medium (water) by gravity flows from the spraying devices onto the non-screening material on the upper screen, it flushes the oversize product and only contributes to the removal of mainly 0-1 mm class. Moreover, such a design of the spray device and its location in the screen do not allow preliminary screening of a significant portion of grains smaller than the boundary separation size.

A device for separating bulk materials is known. This device includes a separation chamber with a loading device and fraction receivers, inclined vibration surfaces installed in the separation chamber with a gap one under the other and stepwise from the loading

adaptations to the receiver of large fractions, a screening surface associated with the lower vibro-surface, nozzles for suctioning the dust and gas stream from the spaces of the separation chamber above

downhill with a vibration surface, a gas injection system into the separation chamber, gas distribution sieves transversely installed in the gaps between the outlet end of each overlying and underlying vibration surfaces along the entire length and height of these gaps, while in each gap gas distribution sieves are combined in a package and installed in a package with sequential downsizing

openings to the downstream end of the vibro-surfaces, and the space behind the latter from the upstream end of the gas distribution sieve in each bag is individually communicated with the gas injection system into the separation chamber. In addition, the gas distribution sieves in each package are combined into a cassette, and each cassette and each gas distribution sieve in the cassette is removable,

The source material in the free fall zone from the upper to the lower vibrational surfaces is treated with a stream of compressed air flowing through the gap in the direction of transporting the material along the vibrational surfaces, while fine grains removed from the treated layer are sucked through the nozzles from the chamber space above the passages from the upper to lower vibrational surfaces, coarse material then goes to a similar treatment in the next cascade of vibrational surfaces.

The disadvantage of this device is the low screening efficiency due to incomplete air displacement of small grains from a thick continuous stream of material, the small pore sizes between the particles of which create significant resistance to air passage. Under such conditions

increasing the pressure or air flow rate to ensure efficient displacement of the fine grains from the bed results in the removal of grains in the dust-air mixture over a predetermined separation size. In addition, the inability to carry out control

the screening of the dust-air mixture leads to the arrival of grains larger than the separation size into the sublattice product, and the forced removal of the dust-air mixture in the direction opposite to the direction of gravity requires additional energy consumption to drive the fan or smoke exhauster and can only be used to separate the grains of finely dispersed material . Such a device design cannot be used for wet screening of bulk materials.

The closest technical solution to the invention is a device for separating bulk materials. This device includes a screening surface, a loading vibro-surface installed with a gap above the screening surface with the formation of a step between them, additional screen sections, a device for removing small grains from the material flow, made in the form of a nozzle for a working medium installed in the gap between the loading vibro-surface and the screening surface over their entire width and directed against the movement of the material along the vibro-surface, with additional sections of screens located under nonperforated The vibration-free surface is arranged in a planed area in the plane of the screening surface and is removable, and the nozzle along its entire length is made in the form of separate alternating chambers isolated from each other, connected through one to individual sources of pumping of the working medium.

A disadvantage of this device is the low screening efficiency due to local exposure to the material layer in the free fall zone. In this case, the trace of the jet of the working medium on the material flow slightly increases the size of the nozzle outlet. This limits the area of influence of the working medium on the screened material at the moment of free fall and, therefore, reduces the probability of dropping out fine grains. In addition, due to the fact that the nozzle is stationary, not associated with a rumble, the jet of the working medium does not oscillate, and its alternating pulsating components are absent. This worsens the loosening of the material and the movement of particles relative to each other, does not allow the formation of a sufficient number of pores in the layer for intensive passage of particles of the working medium through the layer of the screened material at the moment of free fall. Due to the lack of horizontal displacement of the nozzles, the regulation of the required boundary separation size and the search for a rational mode of operation of the device are limited. In addition, for mounting the nozzle vertically or turning it, separate fastening units are provided, which complicates the design of the device and its maintenance.

The aim of the invention is to improve the quality of separation of fine grains due to the intensification of separation of granular

0 material by size in the zone of its free fall.

This object is achieved in that in a device for separating bulk materials, including a screening surface 5, a loading vibro-surface mounted with a gap above the screening surface, a nozzle for supplying a working medium mounted in guides for moving it vertically in the gap

0 between the loading vibro-surface and the screening surface over their entire width and directed against the movement of the material along the vibro-surface, the guides made with curved pauses are rigidly fixed on the lower side of the vibro-surface, and the nozzle is mounted with the ability to move it horizontally and change the angle of inclination. The proposed design will allow

0 to improve the quality of separation of small grains due to the intensive separation of bulk material in the zone of its free fall, which is achieved by the joint movement of the nozzle and the vibro-surface.

5 In FIG. 1 shows a device, a General view; in FIG. 2 - node I in FIG. 1; in FIG. 3, unit II in FIG. 2; in FIG. 4 is a view B in FIG. 3; in FIG. 5 is a general view of the device with the additional sieve removed.

0 The device consists of a box 1, a drive 2, a loading vibrating 3 and located under it sifting 4 surfaces installed with a gap one under the other and stepwise in the direction

5, unloading large fractions, a nozzle made in the form of a chamber 5, equipped with a converging nozzle 6 along its entire length, the nozzle is fixed in guides 7, rigidly connected to the loading vibro-surface 3. Guides 7 have grooves 8 in which the nozzle moves the outlet of which is directed opposite to the movement of the material along the loading vibro-surface 3 and is located throughout

5, the length of the gap between the opposed bars 9, heated under the corners 10 at the outflow end of the vibrating surface 3, holes 11 are located in front of the nozzle nozzle 6. The nozzle pipe 5 is connected using a flexible pipe 12

with a rigidly fixed pipe 13 for supplying a working medium. To enable the nozzle to move in curved grooves 8 of the guides 7, it is provided on each end side with a fastening assembly including a rigidly fixed stud 14, with washers 15 and nuts 16 fitted thereon.

The screening surface 4 is provided with additional sections of screens 17 located under the non-perforated portion of the vibro-surface 3 in the screening surface and made with the possibility of removal. The sieve sections 17 are fastened with clamps 18 on the beams 19. A bath 20 is located under the device.

A device for separating bulk materials operates as follows. The source material enters the initial non-perforated portion of the vibrating surface 3 and is transported along this surface in a continuous stream across the width of the device. Upon receipt of the material on the perforated portion of the vibrational surface 3 and the grain failure through the holes 11 along the device width, a vertical flow is formed in which the material is discretely separated along the flow width by equal streams in the cross section, while the jets of adjacent flows are displaced relative to each other by an amount equal distance between the working edges of adjacent holes.

The oversize product (mainly large grains that did not fall through the hole 11, the size of which is much larger than the specified separation size) is transported along the final non-perforated portion of the vibrational surface 3 and form in the free fall zone onto the screening surface 4 a continuous second vertical flow of material that is not processed jets of the working environment. In the free fall zone, the flow of bulk material passing through the openings 11 is treated with jets of the working medium (water or air-water mixture with wet screening, air with dry screening) coming from nozzle nozzle 6.

Since the nozzle is mounted in guides that are rigidly fixed on the underside of the vibrational surface, the mestroke of the working medium oscillates in the vertical plane. Due to the action of inertial forces, when the direction of the vibrations of the screen changes, the jet of the working medium makes alternating movements in the vertical plane. This significantly increases the angle

open the jet and the zone of its impact on the screened material at the moment of free fall. The screened material in a vertical flow. Intensively loosened, pores of a larger volume are formed to pass the jet of the working medium.

In this case, the fine grains are intensively displaced by the jets of the working medium from the jets of the vertical flow and enter the initial section of the sieving surface 4, where they easily fall through the openings of the working surface not loaded with material (see Fig. 1). In this case, control hunting is carried out.

(grains larger than the separation size do not enter the sublattice product, but are transported along the working surface of the screen section 17. Large grains from discrete jets of a vertical flow enter the large grain layer after control screening, and then large grains of the second continuous grain enter the upper layer of the mixture of these grains flow coming from the vibrating surface and after the zone

of free fall, the resulting mixture of the over-sieve product is finally refined on the sieving surface 4. The under-sieve product enters the screen 20. At a low content of large (substandard) grains in the material displaced from the jets passing through the holes 11, this material is sent without a screen to the screen through the gap a and into the screen 20 of the screen (see Fig.

5). Depending on the size of the source material, the required boundary separation size, volumes and pressure of the working sphere to ensure the necessary sieving quality, the jets of the working medium may

applied at different angles to the stream of discrete jets of material, to different sections of the stream in the free fall zone, while the nozzle can be located at different distances from the discrete jets of material. This makes it possible in each case to create rational conditions for separation and to provide an increase in screening efficiency.

The creation of these conditions is carried out

in the following way.

When the device stops, the nuts 16 on the studs 14 are untwisted. This weakens the fastener assembly (the washers 1 with the nuts 1 do not press against the surface of the guides 11) and the nozzle studs 14 can easily move along curved grooves 8 and rotate about their axis. In this case, the nozzle may rise or fall relative to the vibrating surface 3, move away or approach

relative to discrete streams, vary the angle of inclination. There is a wide range of nozzle position choices. Having chosen the required nozzle position, the position of the studs 14 is fixed by squeezing on each side of the guide 7 with washers 15 and nuts 16. Thus, the nozzle is rigidly mounted on the guides 7 and oscillates in the same mode as the vibration surface 3. The proposed device for separation of bulk materials in comparison with the prototype has the following advantages.

The connection of the nozzle with the loading vibro-surface allows due to the action of inertial forces to change the direction of vibrations of the screen to make oscillating movements in the vertical plane of the working medium. In this case, the opening angle of the jet increases (especially at the point of contact with the vertical flow of maTepnafla) and the area of influence of this jet on the material. This contributes to the intensive loosening of the material, the formation of more pores. Under such conditions, small grains are intensively separated by jets of the working medium from a vertical flow (the main mass of the sublattice product is released), the screening surface is unloaded from most of the small product, screening on it occurs in a thin layer and favorable conditions are created for passage of sieve small grains.

Fastening the nozzle with the possibility of movement and rotation in the curved grooves of the guides rigidly connected to two adjacent beams makes it possible to easily move the nozzle vertically, horizontally and rotate around its axis. This allows the nozzle position to be selected so that the separation mode is most rational. Thus, the force of the dynamic action of the jet of the working medium on the screened material is controlled and the desired boundary size of separation is selected. Nodes for mounting and adjusting the nozzle are simpler in design and maintenance.

We did not find similar technical solutions in 5 searches, on the basis of which we can conclude that the proposed technical solution meets the criterion of significant features.

According to the inventive device for screening bulk materials, initial data were selected for the development of technical specifications, a preliminary design of the nozzle design and its mounting on the screen was completed.

The economic effect of using 5 devices is 41148 rubles. With the estimated need of the national economy for the claimed device of 10 units per year, the economic effect of its use will amount to 411,480 rubles. 0

Claims (2)

1. A device for separating bulk materials, including a screening surface, a loading vibro-surface 5 installed with a gap above the screening surface, a nozzle for supplying a working medium installed in the guides to move it vertically in the gap between the loading vibro-surface and the screening surface over their entire width and directed against the movement of the material along the vibro-surface, on the outgoing end of which there are holes in front of the nozzle, characterized by 5 in that, in order to improve the quality of separation of small grains due to the intensification of the process of separation of bulk material in size in the area of its free fall, the guides are rigidly fixed to 0 to the lower side of the loading vibro-surface, and the nozzle is mounted with the possibility of moving it horizontally and changing the angle of inclination. 2. The device according to p. 1, characterized by 5 so that the rails are made with curved grooves for moving the nozzle. well fig.Z Figure 5