SU944681A1 - Pneumatic classifier of grain materials - Google Patents

Description

(54) PNEUMATIC CLASSIFIER OF GRAIN

/ V1ATEPIALOB

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The invention relates to a technique for the processing of building materials and can be used in various sectors of the national economy, where a classification by size of granular materials is necessary.

It has been found that the most efficient apparatus for the separation of the size of granular material in the air stream is the shaft apparatus.

A mine pneumatic classifier is known, including a mine, transfer shelves, loading and unloading devices 1.

However, such a design of the classifier is a two-product apparatus, which makes it difficult to use in enterprises for the production of sand and sand from building rocks.

Also known is a three-product pneumatic classifier, which includes a shaft, separation shelves, a suction nozzle, nozzles for suction of dust, loading and unloading devices.

The three-product classifier is a two-chamber apparatus: the separation of dust fractions takes place in a vertical

the mine, and the separation by size of the dust-free material is in the horizontal chamber, with the air flowing through the suction inlet of the horizontal chamber, and, turning 90 °, moves upwards in the vertical shaft 2.

The main disadvantage of this device is that it does not allow to dedust materials with high humidity with sufficient efficiency, since for separating dust particles adhering to the surface of large grains, high air flow rates are necessary and, consequently, greater air flow, which leads to for an increase in the aerodynamic resistance of the apparatus.

The device of boundary layer suction significantly reduces the resistance, but at the same time the uniformity of the pneumoclassification mode along the shaft height is not ensured, which also degrades the quality of the finished 2Q products when classifying wet materials.

Known pneumatic classifier, including a vertical shaft, dividing shelves, made in the form of an elastic tape fixed on the shafts, inlet

and exhaust pipes, a horizontal chamber with a suction device, loading and unloading devices.

In the pneumatic classifier, the vertical shaft and the horizontal chamber work as independent devices, since the vertical shaft has a leak of atmospheric air through the inlet windows 3.

However, such a decision adversely affects the efficiency of the device, since the volumes of air transported by the fan through the pneumatic classifier increase dramatically, and the classification efficiency decreases.

The purpose of the invention is to improve the classification efficiency by adjusting the aerodynamic regime.

The goal is achieved by the fact that the classifier is equipped with a horizontal chamber and a distribution manifold interconnecting with a distribution manifold with air ducts connected to the inlet manifolds.

The drawing shows the proposed device.

The pneumatic classifier consists of loading 1 and unloading 2 pipes, a shaft 3, a horizontal chamber 4 with a suction pipe 5, an aspiration 6 and a distribution 7 collectors.

The shaft 3 is mounted on a horizontal chamber 4 above the suction inlet 5 and has separation shelves 8 fixed on the shafts of the elastic tape, inlet 9 and exhaust 10 inlets.

The horizontal chamber 4 with a wall 11 is divided into two compartments for a large product 12 and a small product 13.

To the compartment of the small product 13 of the horizontal chamber 4 adjoins the distribution manifold 7, having air ducts 14, connected to the inlet pipes 9 of the vertical clamp.

The air ducts 14 have control chokes 15.

Air classifier works as follows.

The aspiration manifold 6 is connected to the fan via a dust collector. At the same time, an air stream flows through the suction inlet 5 of the horizontal chamber 4, which is divided into two streams in a ratio of, for example, 1: 2 (depending on the number of exhaust nozzles 10 in the shaft), with a smaller part entering the shaft through its lower window, and large - through the distribution manifold 7 with air ducts 14 connected to the inlet nozzles 9.

In the vertical shaft, two classification zones are formed: the upper zone A, where the classification occurs under the influence of the air flow through the lapping nozzles, and the lower zone B,

where the classification takes place under the influence of the air flow coming through the lower window of the Schacht.

The source material — screenings of crushing of rocks, having particle sizes, for example, O-10 mm, through the loading nozzle 1 enter the vertical shaft 3 where in zone A, having been blown with air coming from the inlet nozzles 9, are classified, for example, by boundary grain 0 , 14 mm.

In zone B, the material is blown with air entering through the lower window of the shaft directly from the suction inlet 5, and in this zone there is a final separation of particles having a size less than 0.14 mm.

The thin product of classification through the exhaust window 10 and the suction collector 6 enters the dust collector for deposition, and the intermediate product through the lower window of the shaft 3 enters the horizontal chamber 4, where under the influence of the air flow through the suction nozzle 5, it is classified by the boundary grain 0, 63 or 1.25 mm. The finished products of classification through compartments for large 12 and small 11 products and discharge pipes 2 are removed from the device.

The classification process in the classifier is easy to control by varying the air flow rates over the characteristic sections of the mine with the help of control chokes 16 and can be divided into four or more products.

The most active zone of classification in the vertical shaft is zone B, which is due to the slight aerodynamic resistance of the section between the suction pipe 5 and the lower exhaust pipe 10. Therefore, using adjusting devices, it is possible to ensure the classification of material in this zone according to any boundary grain from 0.14 to 1-2 mm.

The use of a pneumatic classifier will improve the classification efficiency.

Claims (1)

Invention Formula Pneumatic classifier of granulated materials, including a vertical shaft, dividing shelves made in the form of an elastic tape fixed on the shafts, inlet and exhaust pipes, a horizontal camera with a suction device, loading and unloading devices, characterized in that, in order to increase efficiency. classification by adjusting the aerodynamic regime.