RU2333045C1 - Device to separate grain milling products into fractions - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: device to separate grain milling products into fractions incorporates a working chamber housing a rotor with a set of different-area coaxial rotary disks, a branch pipe to feed an aero-dispersed flow, large-size fraction separation chamber, a fine fraction entrapping device, an air discharge branch pipe. Rotary disks are arranged in the working chamber so that their area increases in steps. The first disk, relative to the aero-dispersed flow feed branch pipe, is made integral with the rotor shaft, two following disks being furnished a central bore and separated by a spacer disk. The said device is furnished also with a rotary cone aligned with the rotor, its taper getting widened towards the fine-fraction entrapping device with its lower edge located below the air discharge branch pipe. The aforesaid cone is arranged in the working chamber coupled with the fine-fraction entrapping device and communicates, via a louvered insert, with the casing.

EFFECT: higher efficiency of separation into fractions and lower power consumption.

2 dwg

Description

A device for separating grain grinding products into fractions relates to the field of grain processing industry, namely, to separating grain grinding products into fractions according to the set of physical and mechanical properties, and can be used in mills, cereals, and mini-mills.

Known centrifugal classifier for the separation of highly dispersed materials, comprising a housing with a nozzle for introducing a separating agent, namely gas, a nozzle for supplying a powder-gas mixture, a rotor with a coaxially arranged set of rotating disks of different sizes. A rotor with a set of disks formed a working area. Beats are made on one of the disks. Between the rotor discs is a ring with holes. Under this ring there is a channel for outputting a large fraction, made in the form of an annular gap. The device is also equipped with nozzles for collecting coarse and fine fractions, a nozzle for discharging air with a fine fraction (see USSR author's certificate No. 1620161, IPC ⁵ V07V 7/083).

The main disadvantage of this classifier is that a significant concentration of the starting material will require an increase in the working zone, which will lead to a decrease in the separation efficiency.

Closest to the proposed invention by its technical nature (adopted as a prototype) is a centrifugal air classifier for separating fine powders in the field of centrifugal forces, including a housing with a working chamber and a nozzle for introducing an aerodispersed stream located in the tender part of the working chamber, a sedimentary chamber for a large fraction connected to the working chamber, a device for trapping small fractions, a rotor located in the working chamber, having a set of rotating disks of different sizes, variable cross-section and with a thickness decreasing from the periphery to the axis of rotation of the rotor, a pipe for air outlet with a fine fraction. The dust and gas flow entering the classifier, through the nozzle for introducing the aerodispersed flow, passes through the annular gap between the disks towards the axis of rotation and acquires an angular velocity equal to the speed of the rotor. A large fraction, for particles of which centrifugal forces prevail over viscous, is carried out to the wall of the working chamber and settles, and the stream with a small fraction is carried along further along the rotor up and is discharged through a pipe for air output with a small fraction (see USSR author's certificate No. 5440683, IPC ² B07B 7/083).

A disadvantage of the known centrifugal air classifier is the increased energy intensity of the separation of the product into fractions, caused by the need to transport the solid fraction up.

The present invention solves the problem of reducing the energy intensity of the separation of grain grinding products into fractions.

The problem is achieved in that in a device for separating grain grinding products into fractions containing a working chamber with a rotor located in it, having a coaxially arranged set of rotating disks of different sizes, a nozzle for introducing an aerodispersed flow, a sedimentation chamber for a large fraction connected to the working chamber , a device for capturing a fine fraction, a pipe for air outlet, according to the invention, rotating disks are installed in the working chamber with the formation of successively increasing luminosities, of which the first disk relative to the nozzle for introducing the aerodispersed flow is made in one piece with the axis of the rotor, and two subsequent disks are made with a central hole and are separated by an intermediate disk. The device is equipped with a rotating, coaxial with the rotor, expanding in the direction of the device for trapping the fine fraction of the cone, the lower boundary of which is located below the installation area of the pipe for air outlet. The named cone is placed in a chamber connected to a device for collecting fine particles and sequentially communicated through a louvre insert with a working chamber equipped with a rotor.

The installation of rotating disks in the working chamber with the formation of successively increasing surfaces, the first disk relative to the nozzle for introducing the aerodispersed product made in one piece with the axis of the rotor, and the next two with the Central hole, which allows differentiation to affect the products of grinding grain and generally improve the quality separation of these products. The introduction of an intermediate disk separating the disks with the Central hole, allows you to evenly distribute the aerodispersion flow in the working chamber. Due to the presence of a louvre insert, dusty air is removed from the working chamber, which reduces the explosion hazard of the device. At the same time, the use of two chambers - a working chamber equipped with a rotor, and a chamber equipped with a cone and connected to the working chamber and a device for trapping the fine fraction - makes it possible to direct the selected large and small fractions to different parts of the technological process.

Reducing the energy intensity of the separation of grain grinding products into fractions is achieved by creating a directional movement of the dispersed product, in which the force of gravity acting on the particles is directed in the same direction with the driving aerodynamic force of the air flow, and not in the opposite, as is the case in the prototype.

The proposed device is illustrated by drawings, where figure 1 shows its General view; figure 2 is a cross section of a louvre insert.

The drawings further show the following:

- the direction of motion of the initial aerodispersed flow of the product of grinding the grain, indicated by straight lines with arrows;

- the direction of movement of the large fraction, indicated by straight lines with arrows with a line;

the direction of movement of the small fraction, indicated by arched lines with arrows with a cross;

- the direction of air movement, indicated by lines with arrows with a circle;

- the direction of movement of the aerosols of the fine fraction, indicated by lines with arrows with a cross and a circle.

A device for separating grinding products into fractions contains a working chamber 1 with a rotor 2 located in it, having a coaxially arranged set of rotating disks of different sizes, a nozzle 3 for introducing an aerodispersed flow, a sedimentary chamber 4 for a large fraction connected to the working chamber 1, a device 5 for capture of small fractions, pipe 6 for air outlet. Rotating disks are installed in the working chamber 1 with the formation of successively increasing surfaces. The first rotating disk relative to the nozzle 3 for introducing the aerodispersed flow is made integrally with the axis of the rotor 1, and two subsequent rotating disks 7 and 8 are made with a central hole and are separated by an intermediate solid disk 9. Between the rotor 2 and the disks 7, 8, 9 a working zone.

A rotating cone 10 is mounted coaxially with the rotor 2, expanding in the direction of the fine capture device 5, that is, in the direction of movement of the small fraction. The lower boundary of the cone 10 is located below the installation area of the pipe 6 for air intake. In this case, the cone 10 is placed in the chamber 11, connected to the device 5 for collecting fine particles and sequentially communicated through the louvre insert 12 with the working chamber 1, equipped with a rotor 2.

The proposed device operates as follows. The aerodispersed flow of the product of grinding the grain tangentially through the nozzle 3 of the input of the aerodispersed stream 5 is fed into the working chamber 1, where when moving into the working area between the rotor 2 and the disks 7, 8, 9 acquires the angular velocity of the rotor and disks. In the working area due to the successively increasing surfaces of the rotor 2 and disks 7, 8, the grain grinding product is distributed at angular speeds. The large fraction, having a high rotation speed, is discarded to the walls of the working chamber 1 and is deposited in the sedimentation chamber 4 for the large fraction. The product is transferred from the rotating disk 7 to the rotating disk 8 by means of an intermediate continuous disk 9, which makes it possible to evenly distribute the aerodispersed flow in the working area. The fine fraction aerosol passes into the chamber 11 through the louvre insert 12, where due to a decrease in the cross-sectional area, the speed of the aerodispersed flow increases, an additional suction of dusty air from the working chamber 1 takes place, and enters the cone 10, where it loses speed from the expansion of the cross section and settles into the device 5 to capture the fine fraction. Dusty air is discharged through the pipe 6 for air outlet.

The proposed device provides low energy consumption for the separation of grain grinding products into fractions, and also allows for a single pass to separate the aerodispersed flow of grain grinding products into fractions, separating the grinding products from air.

Claims (1)

A device for separating grain grinding products into fractions, containing a working chamber with a rotor placed in it, having a coaxially arranged set of rotating disks of different sizes, a nozzle for introducing an aerodispersed flow, a sedimentation chamber for a large fraction connected to the working chamber, a device for collecting small fractions, a pipe for air outlet, characterized in that the rotating disks are installed in the working chamber with the formation of successively increasing surfaces, of which the first disk relative to the nozzle for introducing the aerodispersed stream is made in one piece with the axis of the rotor and the two subsequent disks are made with a central hole and separated by an intermediate disk, the device is equipped with a rotating, coaxial with the rotor expanding in the direction of the device for capturing the fine fraction with a cone, the lower boundary of which is located below the installation zone a pipe for air outlet, wherein said cone is placed in a chamber connected to a device for trapping a fine fraction and sequentially communicated through louvres th insert with the working chamber accommodating the rotor therein.

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