RU2550639C1 - Separator of bulk materials - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: separator for bulk materials comprises rows of screening surfaces installed in a zigzag manner one under another, they are made as overhung pins with gaps between them. The lower part of a main channel is fitted by baffles installed over the screening surfaces and made as sieve copying surfaces. The gap between the screening surface and the baffle is related to the average thickness of processed material particles, relative content of admixtures in the processed material and the thickness of grain layer on the screening surface according to the following proportion

where h - gap between the screening surface and the baffle, mm; d - average thickness of processed material particles, mm; s - thickness of grain layer on the screening surface, mm; ε - relative content of admixtures in the processed material.

EFFECT: higher operating efficiency of bulk material separator.

2 dwg

Description

The invention relates to techniques for the separation of bulk materials by size and can find application in the purification of grain and products of its processing in agriculture, flour and cereal industry, as well as coal, mining, construction materials and other industries.

A known separator of bulk materials by size, including a number of installed concave sifting surfaces arranged zigzag one below the other, made in the form of cantileverly fixed fingers with a gap between each other (Russian Patent No. 2071389, IPC B07B 1/04, 1994).

The closest in technical essence to the claimed device is selected as (prototype of Russia No. 2121878, IPC B07B 1/04, 1998) of the prototype bulk material separator, including a number of concave sifting surfaces mounted in a zigzag shape one below the other, made in the form of a console fixed with a gap between fingers. The separator is equipped with an additional row of screening surfaces. In this regard, the separator can emit small and large impurities. The separator corresponds to the expression that determines the optimal parameters of the working bodies:

where h is the spacing of the screening surfaces;

α is the concavity angle of the sieving surfaces;

ι is the length of the screening surface.

A disadvantage of the known device is the large loss of grain material in the Central channel (for separation of large impurities) in the waste of large impurities. This is due to a decrease in the thickness of the layer of the processed material in the channel on the lower sieve and the lower the sieve is located, the less material is fed to it, and therefore the layer thickness also decreases. A study of the operation of such a separator showed that when the layer thickness decreases, grains from the fingers of the sifting sieve are reflected. In this part of the channel, the kernels interact little with each other and acquire free movement. In this state, the grains are reflected from the sieves under the action of elastic forces, which significantly reduces the likelihood of them getting into the sieve hole, and therefore the screening capacity of the material decreases and the amount of grain in the waste of large impurities increases. As for the channels located on both sides of the central channel and designed to isolate fine impurities, the layer thickness practically does not change with the transition from one screening surface to another, therefore there is no need to install reflective surfaces.

An object of the invention is to increase the efficiency of the separator for bulk materials.

The technical task is achieved in that in the separator of bulk materials, including rows of zigzag concave sieving surfaces arranged one below the other made in the form of fingers cantileverly fixed with a gap between themselves, according to the invention, reflectors are installed in the lower part of the main channel above the sifting surface that can regulate the flow in the channel, made in the form of two surfaces of the copying combs, while the gap between the screening surface and the reflector is associated with the average particle thickness of the processed material and the relative impurity content in the processed material and the thickness of the grain layer on the sieving surface satisfies the ratio:

where h is the gap between the screening surface and the reflector, mm;

d is the average particle thickness of the processed material, mm;

s is the thickness of the grain layer on the sieving surface, mm;

ε is the relative impurity content in the processed material.

The invention is illustrated by drawings.

In FIG. 1 shows a longitudinal section through a central channel of a separator; in FIG. 2 - an enlarged section of a number of separating surfaces.

The separator contains rows of separating surfaces: one main 1 (for separating large impurities), two additional zigzag rows 2, located on both sides of it, pneumatic separating channels for separating light impurities and loading device 3. There are guide plates 4 for transferring material between the channels. Pneumatic separation channels are made with the windows of the outlet 5 and the inlet 6 of the air flow. The separator contains nozzles for the withdrawal of fractions obtained after separation of the material: 7 - output purified material; 8 - output of large impurities; 9 - output of fine impurities (nozzles are not shown in the figure), reflectors 10.

Указанное соотношение определяет оптимальные условия эффективной работы сепаратора - интенсивное просеивание частиц при снижении толщины слоя, вследствие чего значительно снижаются потери зерна в отход крупной примеси.Reflectors 10 copy the surface of the sieves and are used to control the flow in the channel. The location of the reflectors 10 can be changed, thereby adjusting the gap h relative to the sifting surface. The gap h depends on the dimensions of the processed material d, on the feed rate of the source material, i.e. layer thickness s, as well as on the content of coarse impurities in the processed material ε, which corresponds to the ratio:

The specified ratio determines the optimal conditions for the efficient operation of the separator - intensive screening of particles with a decrease in layer thickness, resulting in a significant reduction in grain loss in the waste of large impurities.

The specified condition for the efficiency of the separator provides the possibility of its use in the cleaning of the main component, for example, grain from large impurities with a significant reduction in grain losses in waste, for which the separator is equipped with reflectors.

The workflow is as follows.

During the movement of the material along the first screening surface above, a significant part of the grain has time to sift through it. At the same time, the grain material that has not passed through the first screening surface enters the second screening surface, where the screening process of grain and fine impurities continues, then on the third, etc. to the last.

Further, the grain material containing grain and a large impurity to be separated is fed into the separator loading device 3 and then moves downward under the action of gravitational forces, falling on the concave sifting surfaces of the main zigzag row 1. The sifting surfaces of this row have a sufficiently large gap between the cantilevered fingers, which provides the possibility of passage of grain into it, but excludes the possibility of passage of large impurities.

At the same time, up to half of the material is released on the upper section of the channel to isolate large impurities, as a result of which the layer thickness decreases significantly during further cleaning of the material in the channel.

Reflectors 10 are installed on subsequent sieving surfaces, which prevent the grains from reflecting and thus provide a layer of material to be processed on the surface of the sieves.

The material sifting in the upper part of the zigzag channel containing the main part of small and light impurities enters along the guides 4 into additional pneumo-separating channels 2 and through them further into the zigzag rows. In pneumatic separating channels 2, light impurities are separated by an ascending air stream drawn in from windows 5 and 6 and entering through inlets 9 and 10. The fan for suctioning air in FIG. not shown. In two additional channels 2, fine impurities are released.

The use of the proposed separator will improve the cleaning efficiency of the material due to its reduction in losses.

Claims (1)

The separator of bulk materials, including rows of zigzag concave sieving surfaces arranged one below the other, made in the form of fingers cantilevered with a gap between them, characterized in that the lower part of the main channel is equipped with reflectors installed above the sifting surfaces and made in the form of surfaces copying sieves, this gap between the screening surface and the reflector is associated with the average particle thickness of the processed material, the relative impurity content in the sample batyvaemom material and thickness of the grain layer on the surface of the sifting ratio

where h is the gap between the screening surface and the reflector, mm;
d is the average particle thickness of the processed material, mm;
s is the thickness of the grain layer on the sieving surface, mm;
ε is the relative impurity content in the processed material.

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