RU1776453C - Sieve classifying device - Google Patents

Abstract

Usage: a screen classification device can be used to separate minerals in the ceramic, chemical, and other industries. The inventive device contains a housing 1 with a sealed cover 2. In the housing is a sieve

Description

The invention relates to the separation of materials by size and can be used in mineral processing, in the ceramic, chemical, food, pharmaceutical, glass industries and other sectors of the national economy.

A sieve classification device is known, selected as prototype 1.

The device includes a vertical housing with a sealed cover and nozzles for loading the initial product, supplying air, and unloading the finished large and small product. A sieve cylinder and an air distribution rotor in the form of a cylindrical drum with vertical slotted holes in the side surface are coaxially located inside the housing. At the edges of the slotted holes of the cylindrical drum, pegs are fixed, the vertices of which are directed radially to the inner surface of the sieve cylinder. The cylindrical drum is sealed at the ends by walls made with nozzles for air intake. The upper wall is made larger in diameter than the diameter of the drum to ensure that the initial product is scattered on the inner surface of the sieve cylinder, which is fed into the sieve cylinder through a nozzle in the upper housing cover. Once on the upper end wall of the cylindrical air distribution rotor, the initial product is fan-shaped on the inner surface of the sieve cylinder and, picking up with pegs, moves along the sieve. The small product, sifted through a sieve, is carried into the pipe for unloading the small product, made in the lower part of the housing and connected to a suction pneumatic conveying system. The large product remaining on the sieve, under the action of gravity, moves down the inner surface of the sieve cylinder and is discharged through a pipe made in the bottom cover of the sieve cylinder.

The disadvantages of the known device include insufficiently high classification efficiency due to clogging of sieve openings

a cylinder with a separable product when moving the latter along the inner wall of the sieve cylinder between it and the outer surface of the air distribution rotor and when passing through

fine particle openings under pressure from a pneumatic tube.

The purpose of the invention is to increase the classification efficiency,

The goal is achieved in that

in a sieve classification device comprising a vertical casing with a sealed cover and nozzles for loading the initial product, air supply, unloading of finished large and small product, a sieve cylinder located coaxially inside the casing and attached to the casing lid, an air distribution rotor in the form of a cylinder with holes on the side surface mounted coaxially in the sieve cylinder along its entire length with the possibility of rotation, a source of discharge in communication with the discharge pipe of the small product, according to the invention, the bottom of the housing is communicated with a pipe for

output of a large product, the latter is sealed and connected to the atmosphere through an additional air supply pipe with a flow regulator, a small product output pipe is located in

the housing cover inside the sieve cylinder, the loading nozzle is made with a diffuser at the output end and is located in the lower part of the housing coaxially with the conical bottom of the sieve cylinder, and the bottom of the air distribution rotor is made conical.

The invention is as follows.

The initial product, entering the loading pipe together with the sucked air through the diffuser into the lower conical part of the housing, receives a directed upward movement. Placing the diffuser coaxially with the conical bottom of the sieve cylinder facilitates preliminary gravity classification and separation of the large product, while large particles are not transported to the sieve at all, but settle in the lower cone and are removed through the nozzle to discharge the large product. The product separated from the coarse particles moves to the openings of the sieve cylinder and, sifted through a sieve, closes its openings. When the cylinder of the air distribution rotor rotates, air jets directed from the rotor to the inner surface of the sieve cylinder create cleaned zones on the sieve that move synchronously with the movement of the jets of cleaning air. The dusty air flow, approaching the sieve cylinder from its outer side, rushes to these moving cleaned sieve zones and acquires an additional rotational movement synchronous with the rotation of the air distribution rotor. The flow swirls and, under the action of the resulting centrifugal force, the particles are centrifugally classified. The material separated from the mesh of the sieve by air jets forms a material flow sliding along the walls of the body, part of which, falling into the gap between the walls of the body and the diffuser, is sent to the nozzle for unloading a large product. Another part of the sliding flow enters the diffuser and, carried away by the feed stream, is again directed to the classification,

Depending on the ratio of the parts of the material that is discharged and returned to the classification process, the degree of recirculation is determined. The degree of recirculation can be controlled by the air supply through an additional pipe made on the discharge pipe of a large product, or by the size of the gap between the diffuser and the cone wall in the housing by changing the position of the diffuser on the supply pipe of the initial product.

In FIG. 1 is a schematic general view of a screen classification device; in FIG. 2 is a section AA in FIG. 1.

The screen classification device consists of a cylindrical body 1 with a sealed cover 2 and feed pipes 3, for unloading a small product 4 of a large product 5. A screen cylinder 6 is mounted and attached to the cover 2 with openings 7 with holes 7 in the side surface. In the conical bottom of the sieve cylinder 6 there is a pipe 8 for supplying air with a flow regulator 9. Coaxially with the sieve cylinder 6 in the housing

an air distribution rotor 10 is installed in the form of a cylinder with a conical bottom, openings 11 on the side wall and a nozzle 12 that communicates with the atmosphere and 5 is mounted in bearings 13 to a sealed cover 2. The air distribution rotor is rotated by an electric motor 14. A large product discharge nozzle 5 sealed with a shipper 15

0 and is connected to the atmosphere by an additional air supply pipe 16 with a flow regulator 17. The pipe 3 for supplying the initial product is made with a funnel 18 for loading the source material and diffuser 19 at the output end and is located in the lower part of the housing coaxially with the conical bottom of the sieve cylinder 6. A pipe 4 for unloading the small product is located in the cover 2 of the housing inside the sieve cylinder 6 and through a cyclone to separate fine particles from air, it is connected to a discharge source, for example, a vacuum pump or a fan suction pipe (not shown in Fig.).

5 The device operates as follows.

The source material through the pipe 3 together with the air sucked into the funnel 18 through the diffuser 19 enters the lower

Q part of the housing 1 classifier. The diffuser 19 is placed coaxially with the conical bottom of the sieve cylinder 6, thereby upward flow of the source material is subjected to preliminary gravitational

with classification. Large particles settle in the lower cone and are removed through pipe 5 to discharge the large product. The dusty air stream separated from large particles by the action of discharge moves to

The openings 7 of the screen cylinder b, where it is classified, and the small product, passing the screen openings 7, is guided through the pipe 4 of the output of the small product into the cyclone to separate the fine particles from the stream

from the air. The air entering through the nozzle 8 into the lower conical part of the sieve cylinder 6 does not allow small particles to settle in the conical part, i.e. actually squeezes them into the working space, directed to the small product unloading pipe 4. Air is supplied to the rotating air distribution rotor 10 through the pipe 12, which is mounted in sliding bearings 13 to the sealed cover 2, and through the holes 11 it enters the openings 7 of the screen cylinder 6 and cleans them. Particles separated from the openings of the sieve 7 slide down the walls of the housing and fall into the conical bottom of the housing and through the nozzle 5 are removed into the hopper of the finished large product. The large particles removed through the nozzle 5 are supported by the air flow coming through the additional nozzle 16 and are sent to the feed stream for reclassification, thereby increasing the classification efficiency. Sealing of the nozzle 5 with a loader 15 eliminates dusting in this classification zone.

Thus, the device makes it possible to perform sieving on powdered sieves in a dry state under vacuum, which expands the scope of application of the apparatus and creates conditions for the almost complete absence of dusting of fine powders both at the places of loading and at the places of unloading of separation products.

Such a design allows classification on ultra-thin screens on an industrial scale with virtually no wear.

Claims (1)

The claims Screen classification device comprising a vertical housing with a sealed lid and loading nozzles source material, air supply, unloading of finished large and small product, a sieve cylinder located coaxially inside the housing and fixed to the housing cover, an air distribution rotor in the form of a cylinder with holes on the side surface, mounted coaxially in the sieve cylinder along its entire length with rotation A discharge source in communication with a discharge pipe of a small product, characterized in that, in order to increase separation efficiency, the bottom of the housing is communicated with a pipe for discharging a large product the one that is sealed and connected to the atmosphere by means of an additional air supply pipe having a flow regulator, a small product outlet pipe is located in the housing cover inside the screen cylinder, the bottom of the latter and the air distribution rotor bottom being conical, and the loading pipe located in the lower part of the housing , made with a diffuser at the output end mounted coaxially with the conical bottom of the sieve cylinder.