DEVICE FOR SEPARATION AND REMOVAL IMPURITIES FROM GRANULAR MATERIAL

Abstract

A device for separation and removal of light impurities from granular material has a cylindrical body, in the upper part of which is located a motor-driven fan that sucks air and an outlet channel for light impurities, below which there is axially mounted a feed channel connected to a container of granular material, and in the lower part of the body there is axially located a cylinder with an outer diameter smaller than the inner diameter (d) of the body, containing a centrifugal guide located under the outlet of the feed channel, whereas below the centrifugal guide, on the inner wall of the cylinder are fixed uniformly spaced directing plates at a certain distance from each other, their ends being pointed towards the axis of the device, and between the body and the cylinder there is a chute for purified material. There is a plurality of openwork hinders.

Claims

1. A device for separation and removal of light impurities from granular material, having a vertical cylindrical body, in the upper part of which there is located a motor-driven fan that sucks air and an outlet channel for light impurities, below which there is axially mounted a feed channel connected to a container of granular material, and in the lower part of the body there is axially located a cylinder with the outer diameter smaller than the inner diameter of the body, comprising a centrifugal guide in the form of an axial member on the surface of which there are mounted directing elements with their ends being pointed towards the inner wall of the cylinder, said centrifugal guide being located under the outlet of the feed channel, whereas below the centrifugal guide, on the inner wall of the cylinder there are mounted directing plates evenly spaced from each other, their ends being pointed towards the axis of the device, and between the body and the cylinder there is a chute for purified material in the form of two symmetrical troughs connected together at the top, wrapping up spirally around the cylinder, characterised in that there is a plurality of openwork hinder plates (14) fixed to the outer surface of the feed channel (7), in various transverse planes in each plane, their ends being pointed obliquely upwards towards the inner wall of the body (1), and inside the feed channel (7), above the outlet (10) there is axially located a multi-conical reducer (16) slowing down the gravitational flow of the granular material.

2. The device according to claim 1, characterized in that the hinder plates (14) are fixed to the surface of the feed channel (7) at an angle (a) which fulfils the condition 25°≤α≤75°.

3. The device according to claim 1, characterized in that the outer surface of the feed channel (7) is cylindrical.

4. The device according to claim 1, characterised in that the outer surface of the feed channel (7) forms a regular polygon in cross-section.

5. The device according to claim 1, characterized in that the multi-conical reducer (16) consists of an inverted open truncated cone (17), below which there is located a smaller dispersing cone (18).

6. The device according to claim 1, characterized in that the outlet (10) of the feed channel (7) is funnel-shaped.

7. The device according to claim 1, characterized in that the ratio of the area (G) of the cross-section of the interior of the feed channel (7) to the area (S) of the cross-section of the interior of the body (1) fulfils the condition 0.012≤G/S≤0.2.

8. The device according to claim 1, characterized in that the ratio of the area (P) of the cross-section of the interior of the cylinder (9) to the area (S) of the cross-section of the interior of the body (1) fulfils the condition 0.1≤P/S≤0.85.

9. The device according to claim 1, characterized in that the openwork hinder plates (14) are fixed to the surface of the feed channel (7) at equal angular distances between each other in each transverse plane, the plates (14) in one plane being shifted with respect to the plates (14) in an adjacent plane by half of the angular distance between the plates (14).

10. The device according to claim 1, characterized in that the openwork hinder plates (14) are fixed to the surface of the feed channel (7) at different angular distances between each other in each transverse plane, the plates (14) in one plane being positioned in the gaps between the plates (14) in an adjacent plane.

11. The device according to claim 9, characterized in that the ratio of the total surface area (F) of all the hinder plates (14) in all transverse planes in a plan view to the surface area (S) of the cross-section of the interior of the body (1) fulfils the condition 0.3≤F/S≤0.95.

12. The device according to claim 10, characterized in that the ratio of the total surface area (F) of all the hinder plates (14) in all transverse planes in a plan view to the surface area (S) of the cross-section of the interior of the body (1) fulfils the condition 0.3≤F/S≤0.95.

13. The device according to claim 1, characterised in that the openwork hinder plates (14) have small through openings (15) on the entire surface (F).

14. The device according to claim 13, characterised in that the total surface area of all the through-openings (15) on each hinder plate (14) covers from 5% to 60% of the surface area (F) of the hinder plate (14).

15. The device according to claim 1, characterized in that the surface (F) of the hinder plates (14) is a rectangle.

16. The device according to claim 15, characterised in that the hinder plates (14) have an arched outline with a radius of curvature (r) which fulfils the condition 0.3≤r/d≤5.0, wherein (d) is the inner diameter of the body (1).

17. The device according to claim 1, characterized in that in the lower part of the body (1), near the end of the troughs (19), there is radially positioned an outlet (20) for the purified material provided with a hinged flap (21).

Description

[0005] A device according to the invention is presented in an embodiment in the drawing, where

[0006] FIG. 1 presents a schematic view of the device in axial section showing openwork hinder plates arranged on the surface of the feed channel in three different transverse planes,

[0007] FIG. 2—a view of the feed channel, with hinder plates having curved outline,

[0008] FIG. 3—the device of FIG. 1 in V-V cross-section showing hinder plates in a plan view, and

[0009] FIG. 4—a single rectangular hinder plate in a perspective view.

[0010] A device according to the invention has a cylindrical body 1, in the upper part of which there is positioned a fan 2 that sucks air, driven by a motor 3, and an outlet channel 4 for light impurities, the outlet channel being provided with an adjustable aperture 5. The body 1 is mounted on a support structure 6 such that its end is positioned above the ground level. Below the fan 2, in the axis of the body 1, there is positioned a feed channel 7 being dosed at the top, connected to an external container 8 of granular material. In the lower part of the body 1 there is axially located a cylinder 9 with an outer diameter smaller than the inner diameter d of the body 1. Inside the cylinder 9, under the outlet 10 of the feed channel 7, there is a centrifugal guide in the form of an axial member 11, on the surface of which there are fixed directing elements 12 with their ends being pointed towards the inner wall of the cylinder 9. Underneath the centrifugal guide, on the inner wall of the cylinder 9, there are fixed, evenly spaced at a certain distance from each other, directing plates 13 with their ends being pointed towards the axis of the device, the directing plates constituting the centripetal guide. On the outer surface of the feed channel 7, in various transverse planes, there are fixed a plurality of openwork hinder plates 14 in each plane, their ends being pointed obliquely upwards towards the inner wall of the body 1. The hinder plates 14 are fixed on the surface of the feed channel 7 at an angle from 25° to 75°, preferably 45°. The outer surface of the feed channel 7 may be cylindrical or may have the shape of a regular polygon in cross-section. The openwork of the hinder plates 14 is obtained by a plurality of small through-openings 15 made on the entire surface F of the plate 14, whereby the total surface area of all the through-openings 15 may cover from 5% to 60% of the surface F of the hinder plate 14. The surface F of the hinder plates 14 is a rectangle, whereby the plates 14 may have an arched outline with a radius of curvature r which amounts from 0.3 to 5.0 of the inner diameter d of the body The value of the ratio of the area G of the cross-section of the interior of the feed channel 7 to the area S of the cross-section of the interior of the body 1 amounts from 0.012 to 0.2, whereas the value of the ratio of the area P of the cross-section of the interior of the cylinder 9 to the area S of the cross-section of the interior of the body 1 amounts from 0.1 to 0.85. The openwork hinder plates 14 can be attached to the surface of the feed channel 7 at equal angular distances between each other in each transverse plane, the plates 14 in one plane being shifted with respect to the plates 14 in an adjacent plane by half of the angular distance between the plates 14. Alternatively, the openwork hinder plates 14 can be attached to the surface of the feed channel 7 at different angular distances between each other in each transverse plane, the plates 14 in one plane being positioned in the gaps between the plates 14 in an adjacent plane. The ratio of the total surface area F of all hinder plates 14 visible in a plan view in all transverse planes in the cross-section V-V in FIG. 3 to the surface area S of the cross-section of the interior of the body 1 amounts between 0.3 and 0.95. Inside the feed channel 7, above the outlet 10, there is axially positioned a multi-conical reducer 16 for slowing down the gravitational flow of the fed granular material, which consists of an inverted open truncated cone 17 below which is provided a smaller dispersing cone 18, the outlet 10 of the feed channel 7 being funnel-shaped. In the space between the body 1 and the cylinder 9, there is a chute for purified material consisting of two symmetrical troughs 19 connected to each other at the top edge of the cylinder 9 and wrapping up spirally around the cylinder 9 so that their ends are positioned at the outlet opening 20 for the purified material arranged radially in the body 1, at its lower edge, on the opposite side in relation to the connection of the troughs 19. The outlet opening 20 is covered by a tilting flap 21 hingedly mounted on the body 1.

[0011] The operation of the device is effected as follows: the granular material to be purified, located in the external container 8, flows by gravity into and down the feed channel 7, and falls onto the inverted open cone 17 and further onto the dispersing cone 18 of the multi-conical reducer 16 thus losing its kinetic energy and with the speed slowed down, it falls out through the funnel-shaped opening 10 directly onto the directing elements 12 of the centrifugal guide, which, dispersing the material evenly in space, transfer it towards the directing plates 13 constituting the centripetal guide. The material thus dispersed is forced in the opposite direction by the stream of air sucked in by the fan 2, which snatches the purified material together with light impurities upwards towards the openwork hinder plates 14, whereas heavy contaminants such as stones, ears or weed seeds fall out through the bottom of the cylinder 9. Light impurities in the air stream enter upwardly between the openwork plates 14 and the space between the ends of the plates 14 and the inner surface of the body 1, as well as through the through-openings 15 in the plates 14 and are removed through the outlet channel 4 to the outside, whereas the purified granular material loses kinetic energy onto the surfaces of the hinder plates 14, moving towards the inner wall of the body 1, and then slides by gravity along this wall onto the troughs 19 of the chute, along which it is led to the outlet opening 20. The pushing material causes tilting of the flap 21 thus enabling the discharge.