CLASSIFYING DEVICE FOR CLASSIFYING A GRANULAR MATERIAL FLOW

Abstract

A classifying device may be used to classify a granular material flow. The classifying device may comprise a first inlet that allows a first material flow into the classifying device, a second inlet that allows a second material flow into the classifying device, a static classifier, and a dynamic classifier. The static classifier may be positioned such that the static classifier at least partially surrounds the dynamic classifier. The classifying device may comprise a distributing device that is designed in such a manner that it supplies the material flow of the first inlet to the static classifier and the material flow of the second inlet to the dynamic classifier.

Claims

1.-12. (canceled)

13. A classifying device for classifying a granular material flow, the classifying device comprising: a first inlet for allowing a first material flow into the classifying device; a second inlet for allowing a second material flow into the classifying device; a static classifier; a dynamic classifier, wherein the static classifier is positioned such that the static classifier at least partially surrounds the dynamic classifier; and a distributing device that is configured to supply the first material flow from the first inlet to the static classifier and to supply the second material flow from the second inlet to the dynamic classifier.

14. The classifying device of claim 13 wherein the distributing device comprises at least one rotatable disk.

15. The classifying device of claim 13 wherein the distributing device comprises at least one region that is connected to a housing of the classifying device.

16. The classifying device of claim 13 wherein the distributing device comprises: a first rotatable disk for supplying the first material flow from the first inlet to the static classifier; and a second rotatable disk for supplying the second material flow from the second inlet to the dynamic classifier.

17. The classifying device of claim 16 wherein at least one of the rotatable disks is connected to a driveshaft.

18. The classifying device of claim 16 wherein at least one of the rotatable disks is a ring-shaped disk.

19. The classifying device of claim 16 further comprising connecting means that connects the first and second rotatable disks.

20. The classifying device of claim 16 wherein at least one of the rotatable disks comprises a plurality of guiding elements on a surface.

21. The classifying device of claim 20 wherein the plurality of guiding elements are rod-shaped and extend radially outward.

22. The classifying device of claim 20 wherein the plurality of guiding elements comprise a connecting means that connects the first and second rotatable disks.

23. The classifying device of claim 20 wherein the plurality of guiding elements are of plate-like design.

24. A grinding plate for comminuting granular material, the grinding plate comprising: at least one grinding apparatus; and a classifying device that is connected to the at least one grinding apparatus, wherein the classifying device comprises: a first inlet for allowing a first material flow into the classifying device, a second inlet for allowing a second material flow into the classifying device, a static classifier, a dynamic classifier, wherein the static classifier is positioned such that the static classifier at least partially surrounds the dynamic classifier, and a distributing device that is configured to supply the first material flow from the first inlet to the static classifier and to supply the second material flow from the second inlet to the dynamic classifier.

Description

PREFERRED EXEMPLARY EMBODIMENTS OF THE INVENTION

[0033] The invention is explained in more detail below using a plurality of exemplary embodiments with reference to the attached figures.

[0034] FIG. 1 shows a schematic sectional illustration of a classifying device with a distributing device according to one exemplary embodiment.

[0035] FIG. 2 shows a schematic illustration of a top view of a distributing device according to a further exemplary embodiment.

[0036] FIG. 3 shows a schematic sectional illustration of a distributing device according to a further exemplary embodiment.

[0037] FIG. 1 shows a classifying device 10 with a static classifier 20 and a dynamic classifier 22. In the exemplary embodiment from FIG. 1, the static classifier 20 is arranged around the dynamic classifier 22 and is of cylindrical ring-shaped design. Furthermore, the static classifier comprises an outer cylindrical wall 29 and, arranged radially inwardly with respect thereto, a first outer static flow device 25 and a second inner static flow device 26. The first and second flow devices 25, 26 each comprise parallel guide vanes, wherein the guide vanes of the first flow device 25 are positioned in a radially dropping manner. The guide vanes of the second flow device 26 are positioned in an opposed manner with respect to the guide vanes of the first flow device 26. A cylindrical static classifying zone 27 is formed between the first and the second flow device 25, 26.

[0038] Within the static classifier 20, the dynamic classifier 22 is arranged radially inward of the second flow device 26. The dynamic classifier 22 comprises a rod basket 23 with rods running in the axial direction. The rod basket 23 is driven in a rotating manner via a driveshaft 28 attached to the upper end of the rod basket. In the exemplary embodiment in FIG. 1, the dynamic classifier 22 is arranged coaxially with respect to the static classifier 20 and rotationally symmetrically with respect to the drive spindle 28. The dynamic classifying zone 31 is formed between the classifying basket and the second flow device 26. Furthermore, vertical rod-shaped guiding elements (not illustrated in FIG. 1) which are attached to the flow device 25 can be arranged in the dynamic classifying zone 31.

[0039] A distributing device 42 which comprises a first disk 38 and a parallel second disk 40 is arranged at the upper end of the rod basket 23. The second disk 40 is of the same diameter as the rod basket 23, is fixedly connected to the latter and forms a cover of the cylindrical rod basket 23. The first disk 38 is arranged parallel to the second disk 40 and above the latter and is of ring-shaped design, with a recess in the center. A passage is formed between the first disk 38 and the second disk 40. The first disk 38 and the second disk 40 are connected to each other in a manner not illustrated in FIG. 1, and therefore rotation of the second disk 40 which is fixedly connected to the rod basket 23 brings about rotation of the first disk 38.

[0040] A first inlet 14 and a second inlet 12 for letting a material flow into the classifying device are arranged above the distributing device 42. In the exemplary embodiment according to FIG. 1, the inlets 12, 14 comprise concentric openings which are arranged around the driveshaft 28 and comprise inlets depicted in a tubular manner, wherein the inlet opening of the first inlet 14 is arranged above the inlet opening of the second inlet 12. The driveshaft 28 of the dynamic classifier 22 extends centrally in the axial direction through the second inlet 14.

[0041] A classifying air duct 36 is arranged around the static classifier 20. In the exemplary embodiment illustrated in FIG. 1, the classifying air duct 36 is schematically illustrated laterally, on the left side of the static classifier 20. The classifying air duct 36 is fluidically connected to the static classifier, and therefore classifying air can flow from the outer wall 29 of the static classifier 20 through the outer static flow device 25 into the classifying zone 27 of the static classifier 20. The flow direction of the classifying air is illustrated in FIG. 1 by the arrow direction in the classifying air duct 36.

[0042] FIG. 1 furthermore shows three outlets 30, 32, 34 for letting the classified material flow out of the classifying device 10. The first outlet 30 comprises a duct which is arranged below the static classifying zone 27 in such a manner that the material rejected in the static classifying zone drops into the duct and emerges out of the classifying device 10 through the outlet 30. The second outlet 32 comprises a duct which is arranged below the dynamic classifying zone 31 in such a manner that the material rejected by the dynamic classifier drops into the duct and emerges out of the classifying device 10 through the outlet 32. The third outlet 34 comprises a duct which is arranged below the rod basket 23 and through which the material which has passed through the static and the dynamic classifying stages 27, 31 emerges from the classifying device 10 together with the classifying air within the rod basket 23.

[0043] During the operation of the classifying device 10, a coarse material flow flows in the arrow direction 16 through the first inlet 14 onto the first disk 38 which is driven in a rotating manner via the drive spindle 28. Rotation of the first disk 38 causes the material to move radially outward on the disk 38 and to pass from above into the static classifier 20 and into the static classifying zone 27. The impact of the material flow against the disk 38 and the rotation of the disk 38 additionally ensure that the material is deagglomerated.

[0044] From the outer wall 29 of the static classifier 20, classifying air enters the static classifier 20 and flows through the outer flow device 25 counter to the material flow flowing through the static classifying zone 27. In the static classifying zone 27, the material flow is deflected radially inward toward the inner flow device 26 by the entering classifying air. The coarse material flows through the static classifying stage 27 and drops downward toward the first outlet 30. The finer material is blown by the classifying air through the inner flow device 26 into the dynamic classifying zone 31. In the dynamic classifying zone 31, the coarse material drops downward toward the second outlet 32 and the finer material passes through the rods of the rod basket 23 into the interior of the rod basket. The finer material in the interior of the rod basket 23 drops downward toward the third outlet 34.

[0045] The classifying device 10 comprises three outlets 30, 32, 34 for three different grain fractions of the material flow. The material flow flowing into the classifying device 10 through the first inlet 14 is classified into three different grain fractions which leave the classifying device 10 through three different outlets 30, 32, 34.

[0046] The material flow entering the classifying device 10 through the second inlet 12 runs through the classifying device in the arrow direction 18 and first of all flows onto the second disk 40 which is driven to rotate by the drive spindle. The material is moved radially outward by the rotation of the disk 40 and enters the dynamic classifying zone 31 adjoining the second disk 40 in the dynamic classifier 22. As already described with respect to the material flow flowing into the classifying device 10 through the first inlet 14, the coarser material drops downward through the dynamic classifying zone to the second outlet 32. It is conceivable to subsequently at least partially combine the material emerging through the outlet 30 and the material emerging through the outlet 32 and to supply them to a grinding device.

[0047] The finer material enters the rod basket 23 and is discharged downward together with the classifying air in the direction of the third outlet 34. It is likewise conceivable to allow the material which has passed through the rod basket 23 to emerge out of the classifying device 10 above the dynamic classifier 22, wherein the outlet 34 is arranged above the rod basket in a manner not illustrated in FIG. 1.

[0048] The material entering the classifying device through the second inlet 12 is classified into two grain sizes, wherein the finer material is let out of the classifying device through the third outlet 34 and the coarser material through the second outlet 32.

[0049] The classifying device 10 enables two material flows of different grain sizes to be fed into the classifying device, wherein the first material flow is supplied both to the static classifier 20 and to the dynamic classifier 22 and the second material flow is supplied exclusively to the dynamic classifier 22. This permits a coarse material flow from, for example, a roller mill to be let into the classifying device 10 through the first inlet 14, and a finer material flow from, for example, a ball mill, to be let into same through the second inlet 12.

[0050] The described classifying device 10 permits a considerable space saving since one classifying device is used for two material flows, and an additional classifier can be dispensed with.

[0051] FIG. 2 shows a top view of a distributing device 52 according to an exemplary embodiment. The construction of the distributing device 52 corresponds to the construction of the distributing device 42 described with respect to FIG. 1, wherein the distributing device 52 comprises two disks, a first disk 48 and a second disk 50, which are arranged parallel to each other, wherein the first disk 48 is arranged above the second disk 50. In addition to the distributing device 42 from FIG. 1, the distributing device 52 in the exemplary embodiment from FIG. 2 comprises guiding elements 44 on the first disk 48 and on the second disk 50. The guiding elements comprise elongate struts which are attached on the upper side of the disks 48, 50 and extend in a star-shaped manner in the radial direction. Overall, in the exemplary embodiment in FIG. 2, each disk 48, 50 comprises eight such guiding elements 44.

[0052] During the operation of the classifying device 10, the guiding elements 44 attached to the disks 48, 50 ensure that the material flow is conducted radially outward. In addition, the guiding elements 44 provide an impact surface for the material flow and ensure deagglomeration of the material flow when the latter enters the static classifier 20 and/or the dynamic classifier 22.

[0053] FIG. 3 shows a sectional illustration of the distributing device 54 according to a further exemplary embodiment, wherein the construction of the distributing device 54 substantially corresponds to the construction of the distributing device 52 described with respect to FIG. 2, with the difference that the guiding elements 60 are of plate-like design and extend from the first disk 56 to the second disk 58 and through the latter. The guiding elements 60 from FIG. 3 therefore ensure a simple connection of the first disk 56 to the second disk 58 in addition to the advantages of the guiding elements 44 described with respect to FIG. 2.

LIST OF REFERENCE SIGNS

[0054] 10 Classifying device [0055] 12 Second inlet [0056] 14 First inlet [0057] 16 Material flow [0058] 18 Material flow [0059] 20 Static classifier [0060] 22 Dynamic classifier [0061] 23 Rod basket [0062] 25 Outer static flow device [0063] 26 Inner static flow device [0064] 27 Static classifying zone [0065] 28 Drive spindle [0066] 29 Outer wall [0067] 30 First outlet [0068] 31 Dynamic classifying zone [0069] 32 Second outlet [0070] 34 Third outlet [0071] 36 Classifying air duct [0072] 38 First disk [0073] 40 Second disk [0074] 42 Distributing device [0075] 44 Guiding element [0076] 46 Drive spindle [0077] 48 First disk [0078] 50 Second disk [0079] 52 Distributing device [0080] 54 Distributing device [0081] 56 First disk [0082] 58 Second disk [0083] 60 Guiding elements