Segregation testing apparatus for powders and granular materials

• US 20070137317A1
• Filed: 12/15/2005
• Published: 06/21/2007
• Est. Priority Date: 12/15/2005
• Status: Active Grant

• Current Assignee: Jenike & Johanson, Inc.
• Original Assignee: Jenike & Johanson, Inc.
• Inventors: Prescott, James, McCall, Michael, Hedden, David, Clement, Scott, Brone, Dean, Troxel, Thomas, Hancock, Bruno
• Granted Patent: US 7,347,111 B2
• Time in Patent Office: Days
• US Class Current: 73/863.540
• CPC Class Codes: G01N 1/20 for flowing or falling materials G01N1/2035 G01N1/12, G01N1/14 take precedence

Abstract

A method and apparatus enables testing of sifting segregation of a particulate solid mixture in a storage bin or hopper. The apparatus makes use of a convergently and divergently angled hopper for collecting the mixture. The apparatus further makes use of a minimally-shearing feeder mechanism supplying a desired flow of mixture, with minimal to no sifting segregation, to the angled hopper. A collection mechanism removes samples of the mixture from the angled hopper for analysis with minimal disruption of the particles of the mixture relative to each other. Thus, samples resulting from the testing apparatus, and corresponding method, are highly representative of mixture conditions within a larger storage hopper.

Claims

1. A particulate solids mixture segregation testing apparatus, comprising:

a channel hopper for collecting the mixture, the channel hopper comprising;

a first pair of opposed walls; and

a second pair of opposed walls coupled with the first pair of opposed walls to form the channel hopper;

wherein the channel hopper maintains a discharge opening at a lower end and a supply opening at an upper end, the supply opening providing access by the mixture to an interior chamber of the channel hopper and the discharge opening providing egress of the mixture from the interior chamber of the channel hopper; and

a plurality of mixture sample receptacles disposed to receive mixture supplied to the channel hopper for analysis of mixture segregation.

2. The apparatus of claim 1, further comprising:

a first slidably mounted shuttle having a channel receptacle and a channel block disposed therein, the shuttle configured to slide reciprocally along the discharge opening of the channel hopper between a first position and a second position alternately exposing the channel receptacle to the discharge opening at the first position and the channel block at the second position.

3. The apparatus of claim 2, wherein mixture flows into the plurality of sample receptacles when the channel receptacle has collected mixture from the discharge opening and the first shuttle is in the second position, thereby depositing the mixture in the sample receptacles.

4. The apparatus of claim 2, further comprising:

a piston channel block;

a second slidably mounted shuttle having a piston receptacle and a second channel receptacle disposed therein, the second shuttle configured to slide reciprocally between a first position and a second position;

wherein the piston channel block is configured to pass through the piston receptacle to block the channel receptacle of the first slidably mounted shuttle, and the piston channel block is configured to slide reciprocally between the first position and the second position with the second slidably mounted shuttle; and

wherein mixture supplied to the channel receptacle of the first shuttle flows to the channel receptacle of the second shuttle when the first shuttle is in the second position and the piston channel block is disposed in the piston receptacle of the second shuttle.

5. The apparatus of claim 4, further comprising a third slidably mounted shuttle having the plurality of mixture sample receptacles disposed therein to receive mixture supplied to the channel hopper, the third shuttle configured to slide reciprocally relative to the second shuttle between a first position and a second position.

6. The apparatus of claim 5, further comprising a plurality of staggered apertures aligned with the plurality of mixture sample receptacles to incrementally enable flow of mixture from each of the plurality of mixture sample receptacles one at a time into separate containers as the third shuttle slides toward the second position.

7. The apparatus of claim 1, wherein the first pair of opposed walls are divergently angled relative to each other from the supply opening toward the discharge opening of the channel hopper, the first pair of opposed walls being relatively more distal from each other along the discharge opening.

8. The apparatus of claim 1, wherein the first pair of opposed walls are divergently angled relative to each other along the supply opening from a first wall of the second pair of opposed walls toward a second wall of the second pair of opposed walls, the first pair of opposed walls being relatively more distal from each other along the supply opening proximal the second wall of the second pair of opposed walls.

9. The apparatus of claim 1, wherein the second pair of opposed walls are convergently angled relative to each other from the supply opening toward the discharge opening of the channel hopper, the second pair of opposed walls being relatively more distal from each other proximal the supply opening.

10. The apparatus of claim 9, wherein the second pair of opposed walls are substantially parallel relative to each other along the discharge opening.

11. The apparatus of claim 1, wherein:

the first pair of opposed walls are divergently angled relative to each other from the supply opening toward the discharge opening of the channel hopper, the first pair of opposed walls being relatively more distal from each other along the discharge opening;

the first pair of opposed walls are divergently angled relative to each other along the supply opening from a first wall of the second pair of opposed walls toward a second wall of the second pair of opposed walls, the first pair of opposed walls being relatively more distal from each other along the supply opening proximal the second wall of the second pair of opposed walls;

the second pair of opposed walls are convergently angled relative to each other from the supply opening toward the discharge opening of the channel hopper, the second pair of opposed walls being relatively more distal from each other proximal the supply opening; and

the second pair of opposed walls are substantially parallel relative to each other along the discharge opening.

12. The apparatus of claim 1, wherein the discharge opening is substantially a tapering rectangular shape.

13. The apparatus of claim 1, wherein a first wall of the second pair of opposed walls is sloped relative to a vertical axis, such that mixture supplied to the supply opening proximal the first wall of the second pair of opposed walls slides along the first wall toward the discharge opening.

14. The apparatus of claim 1, wherein the channel hopper is pivotable to vary a degree measurement of a slope of the first wall of the second pair of opposed walls relative to vertical.

15. The apparatus of claim 1, further comprising a removable and replaceable receptacle insert that fits within the channel receptacle of the first slidably mounted shuttle to form a temporary channel block at the location of the channel receptacle.

16. The apparatus of claim 15, wherein the receptacle insert is configured to enter the channel receptacle of the first slidably mounted shuttle, blocking the channel receptacle, and then exit the channel receptacle to re-establish the receptacle when it is desired that the mixture flow from the channel hopper to the channel receptacle.

17. The apparatus of claim 1, further comprising a feeder mechanism disposed to feed the particulate solid mixture to the channel hopper through the supply opening.

18. The apparatus of claim 17, wherein the feeder mechanism feeds the particulate solid mixture at a first wall of the second pair of opposed walls, such that the mixture slides along the first wall toward the discharge opening of the channel hopper.

19. The apparatus of claim 17, wherein the feeder mechanism is minimally-shearing of the particulate solids mixture.

20. The apparatus of claim 17, wherein the feeder mechanism provides a substantially uniform particulate solids mixture flow.

21. A method of sampling a particulate solids mixture for testing segregation of the mixture, the method comprising:

feeding the mixture to a channel hopper, the channel hopper having a supply opening through which the mixture is fed and a discharge opening that is blocked;

collecting the mixture in the channel hopper until a desired amount of mixture is collected; and

unblocking the discharge opening enabling flow of the mixture out of the channel hopper to a plurality of sample receptacles.

22. The method of claim 21, wherein feeding the mixture to the channel hoper comprises feeding the particulate solid mixture to the channel hopper through the supply opening using a feeder mechanism.

23. The method of claim 22, wherein the feeder mechanism feeds the particulate solid mixture at a first wall of the channel hopper, such that the mixture slides along the first wall toward the discharge opening of the channel hopper.

24. The method of claim 22, wherein the feeder mechanism provides a substantially uniform particulate solids mixture flow.

25. The method of claim 21, further comprising positioning the channel hopper and the feeder mechanism to direct the mixture to slide down along a first wall of the channel hopper.

26. The method of claim 22, wherein collecting the mixture in the channel hopper comprises the mixture avalanching upon impacting collected mixture in the channel hopper.

27. The method of claim 22, wherein unblocking the discharge opening comprises reciprocally sliding a first slidably mounted shuttle having a channel receptacle and a channel block disposed therein, the shuttle configured to slide reciprocally along the discharge opening of the channel hopper between a first position and a second position alternately exposing the channel receptacle to the discharge opening at the first position and the channel block at the second position.

28. The method of claim 22, wherein unblocking the discharge opening comprises removing a removable and replaceable receptacle insert that fits within a channel receptacle of a first slidably mounted shuttle to provide access to the channel receptacle for collection of the mixture.

29. The method of claim 22, further comprising transferring the mixture from the channel hopper to a plurality of mixture sample receptacles through the discharge opening of the channel hopper.

30. The method of claim 29, further comprising depositing mixture transferred to each of the plurality of mixture sample receptacles into separate collecting bins for subsequent segregation analysis.

31. The method of claim 30, wherein depositing comprises providing a plurality of staggered apertures aligned with the plurality of mixture sample receptacles to incrementally enable flow of mixture from each of the plurality of mixture sample receptacles one at a time into the separate collecting bins.

32. A feeder for a mixture of particulate solids, comprising:

a fixed bottom plate having a discharge aperture therethrough;

a second plate rotatably slidable over the bottom plate, having a plurality of pass through apertures disposed therein, and having its rotational axis spaced to cause the plurality of apertures to pass sequentially over the discharge aperture of the bottom plate;

a deposition aperture configured to receive the mixture and deposit the mixture on the rotatable second plate in a deposited trail as the second plate rotates; and

a fixed cam plate slidably mounted over the rotatable second plate, the cam plate having a contoured periphery configured to displace the deposited trail radially and progressively outward to the pass through apertures of the second plate as the second plate rotates, supplying the mixture forming the deposited trail to the discharge aperture.

33. The feeder of claim 32, wherein the deposition aperture is integral with the cam plate.

34. The feeder of claim 32, wherein the plurality of pass through apertures are uniformly spaced.

35. The feeder of claim 32, wherein the plurality of pass through apertures have equal dimensions to one another.

36. The feeder of claim 32, wherein the plurality of pass through apertures are sized sufficiently large enough to prohibit the mixture from arching over the pass through aperture due to particle size or particle cohesion.

37. The feeder of claim 32, wherein the plurality of pass through apertures are disposed in a substantially circular pattern in the second plate.

38. The feeder of claim 32, wherein the second plate has a substantially circular shape.

39. The feeder of claim 32, wherein the plurality of apertures are disposed along a periphery of the second plate.

40. The feeder of claim 32, wherein the deposited trail is of uniform cross-section.

41. The feeder of claim 32, wherein the cam plate is configured to displace the deposited trail radially and progressively outward with minimal shearing of the mixture forming the deposited trail.

42. The feeder of claim 32, further comprising a supply hopper disposed to supply the mixture of particulate solids to the feeder.

43. The feeder of claim 32, further comprising a motor configured to rotatably drive the second plate.

44. The feeder of claim 32, wherein the second plate rotates at a rate of between about 2 RPM and about 20 RPM.

45. The feeder of claim 32, wherein the feeder supplies a substantially constant stream of the mixture through the discharge aperture.

46. A method of uniformly supplying a mixture of particulate solids, the method comprising:

receiving a supply of the mixture from a supply source;

directing the mixture to a deposition aperture configured to receive the mixture and deposit the mixture on a rotating plate in the form of a deposited trail as the rotating plate rotates;

displacing the deposited trail radially and progressively outwardly along the rotating plate to a plurality of pass through apertures disposed in the plate;

discharging the mixture from the plurality of pass through apertures and through a discharge aperture.

47. The method of claim 46, wherein the supply source comprises a bin or hopper.

48. The method of claim 46, wherein the deposition aperture is disposed in a fixed cam plate slidably mounted over the rotating plate.

49. The method of claim 46, wherein displacing the deposited trail comprises forming the deposited trail on the rotating plate with a uniform cross-sectional area.

50. The method of claim 46, wherein displacing the deposited trail comprises using a fixed cam plate having a contoured periphery configured to displace the deposited trail radially and progressively outward to the plurality of pass through apertures of the rotating plate as the rotating plate rotates, supplying the mixture forming the deposited trail to the discharge aperture.

51. The method of claim 54, wherein the cam plate is configured to displace the deposited trail radially and progressively outward with minimal shearing of the mixture forming the deposited trail.

52. The method of claim 46, further comprising rotating the rotating plate at a rate that at least substantially hinders the mixture from arching over the plurality of pass through apertures.

53. The method of claim 46, further comprising rotating the rotating plate at a rate of between about 2 RPM and about 20 RPM.

54. The method of claim 46, further comprising providing a motor driving the rotating plate.

55. The method of claim 46, wherein the feeder supplies a substantially constant stream of the mixture through the discharge aperture.