WO1997014489B1

WO1997014489B1 - Hydrocyclone gas separator

Info

Publication number: WO1997014489B1
Application number: PCT/US1996/016784
Authority: WO
Filing date: 1996-10-18
Publication date: 1997-05-15
Anticipated expiration: 1998-04-18

Abstract

A hydrocyclone (2) for separating a combined phase input stream has two nesting truncated downwardly tapering conical members (10, 12) having an annular space (14) therebetween. A tangential inlet (8) leads to the annular space (14) between the cones (10, 12). Alternate embodiments applicable to a hydrocyclone device composed of nesting cylindrical or conical shells forming an annular cyclonic space have passages (39, 41) located on either of the shells (10, 12) to effect an intermediate draw off of a fraction of the flow stream. In addition, a coiled, hollow tube (16) is advantageously situated within the annular space (14) to optimize the flow pattern. Ports (50) may be provided in the hollow tube (16) for removing a gas fraction in counterflow orientation.

Claims

AMENDED CLAIMS

[received by the International Bureau on 27 March 1997 (27.03.97); original claims 5-8, 20 and 21 cancelled; original claims 1, 4, 9, 10 and 16-19 amended; new claims 26-37 added; remaining claims unchanged (8 pages)]

1. A hydrocyclone for effecting separation of a combined phase input stream, comprising an inner shell residing concentrically within an outer shell, the two shells forming an annular space therebetween of constant width, a tangentially oriented inlet means leading into the annular space, and an outlet means communicating with the annular space, wherein the inlet means is circular in cross-section, and wherein a transition means is provided connectingly between the inlet means and an entry point into the annular space wherein the cross-section of a path of flow of the input stream is changed from circular to essentially square to essentially rectangular, wherein the length of the rectangular cross-section parallel to the axis of the two shells is greater than its width.

2. The hydrocyclone of claim 1, wherein the inner shell and the outer shell are each formed as truncated cones tapering in the direction away from the inlet.

3. The hydrocyclone of claim 1, wherein the ratio of the length of the rectangular cross-section of an exit point of the transition means with respect to its width is at least 2:1.

4. The hydrocyclone of claim 1, further comprising passage means in at least one of the inner shell and the outer shell permitting, respectively, passage of a light fraction radially inward through the inner shell and passage of a heavy fraction radially outward through the outer shell.

9. A hydrocyclone for effecting separation of a combined phase input stream, comprising an inner shell residing concentrically within an outer shell, the two shells forming an annular space therebetween of constant width, a tangentially oriented inlet means leading into the annular space, an outlet means communicating with the annular space, a helical means situated within the annular space, bridging the inner shell and the outer shell, and defining a discrete helical path between successive turns of the helical means within the annular space, wherein the helical path is essentially rectangular in cross-section and having a length of the rectangular cross-section taken along an axis parallel to the two shells being greater than its width, the helical path being defined laterally by the outer wall of the inner shell and the inner wall of the outer shell, and longitudinally above by a bottom surface of a first portion of the helical means and below by an upper surface of a succeeding spiral portion of the helical means, the ratio of the length of the rectangular cross- section to the width thereof being at least 2.5:1.

10. A hydrocyclone for effecting separation of a combined phase input stream, comprising an inner shell residing concentrically within an outer shell, the two shells forming an annular space therebetween of constant width, a tangentially oriented inlet means leading into the annular space, an outlet means communicating with the annular space, a helical means situated within the annular space, bridging the inner shell and the outer shell, and defining a discrete helical path between successive turns of the helical means within the annular space, the helical path being defined laterally by the outer wall of the inner shell and the inner wall of the outer shell, and longitudinally above by a bottom surface of a first portion of the helical means and below by an upper surface of a succeeding spiral portion of the helical means, wherein the helical means is formed by a coiled length of a structure having a circular cross- section, wherein the helical means is formed by a coiled length of a structure having a circular cross-section. 11. The hydrocyclone of claim 10, wherein the helical path is a hollow tube, an outside wall of the tube acting to define the helical path as the shorter sides of the essentially rectangular cross-section.

12. The hydrocyclone of claim 11, wherein the hollow tube has tube passage means communicating the space within the helical path defined by the outside of the tube to the hollow inside of the tube for permitting passage of gases therethrough, whereby said helical tube acts to carry said gases upwardly in counter flow with respect to the downwardly spiraling inlet flow within the helical path.

13. The hydrocyclone of claim 12, wherein said tube passage means comprises a plurality of ports located along a bottom half of said tube acting as the upper side of the essentially rectangular cross-section of the helical path.

14. The hydrocyclone of claim 13, wherein the ports are located towards the outer wall of the inner shell.

15. The hydrocyclone of claim 14, wherein the ports are located at an angle of approximately 45° to a horizontal diameter of the tubes.

16. The hydrocyclone of claim 10, wherein the inner shell and the outer shell are each formed as downwardly tapered truncated cones.

17. The hydrocyclone of claim 10, wherein the helical path is essentially rectangular in cross-section, having a length of the cross-section in an axial direction of the shells being greater than a width, wherein the ratio of the length of the rectangular cross- section to the width is at least 2:1.

AMENDEDSHEET(ARTICLE19 18. A hydrocyclone for effecting separation of a combined phase input stream, comprising an inner shell residing concentrically within an outer shell, the two shells forming an annular space therebetween of constant width, a tangentially oriented inlet means leading into a transition zone of the annular space, and an outlet means communicating with the annular space, wherein the inner shell and the outer shell are cylindrical in the region of the transition zone, and are shaped in a region below the transition zone as truncated cones tapering in a direction away from the inlet.

19. The hydrocyclone of claim 18, comprising means for imparting a rectangular profile to the input stream as it flows downwardly and helically through the annular space, the rectangular profile having a greater length than width in a direction parallel to the axis of the shells, wherein the sides of the rectangular profile have an aspect ratio of at least 2:1.

22. A separator apparatus for separating a combined phase input stream composed of at least a gas and a liquid, comprising a hydrocyclone coupled to a secondary separator, the hydrocyclone comprising a shell, an inlet leading into the hydrocyclone, an outlet leading out of the hydrocyclone, an uptake port for removing a light fraction separated from the input stream within the hydrocyclone from a collection area located radially inward from the shell and leading upwardly from a point above a liquid operating level of the hydrocyclone into said secondary separator, a return port leading from said secondary separator downward into the hydrocyclone and having an outlet point below said operating level.

23. The separator apparatus of claim 22, wherein

AMENDED SHEET (ARTICLE 19, the uptake port is formed as an annular space between an outer column and an inner column comprising the return port.

24. The separator apparatus of claim 22, wherein the secondary separator comprises an outer annular chamber being closed at the top thereof, the outer annular chamber communicating with an inner conical annular chamber of constant radial width, coaxial with the outer annular chamber, by way of passage means located on a conical shell defining an inner wall of the outer annular chamber and an outer wall of the inner annular chamber, the inner annular chamber communicating at a truncated bottom thereof with the liquid return outlet, the inner annular chamber communicating with an upwardly tapering conical chamber residing coaxially within the inner annular chamber, and truncated at an open bottom thereof to provide communication with the inner annular chamber to allow passage of separated gas and/or light liquid fraction into the conical chamber and out through an outlet leading out from the top of the conical chamber.

25. The separator of claim 24, wherein the passage means are formed as horizontally oriented vanes which direct the flow tangentially into the inner annular chamber.

26. The hydrocyclone of claim 1, wherein the inner shell and the outer shell are cylindrical in the region of the transition zone, and are shaped in a region below the transition zone as truncated cones tapering in a direction away from the inlet. 27. The hydrocyclone of claim 9, wherein the inner shell and the outer shell are each formed as truncated cones tapering in the direction away from the inlet.

28. The hydrocyclone of claim 9, further comprising passage means in at least one of the inner shell and the outer shell permitting, respectively, passage of a light fraction radially inward through the inner shell and passage of a heavy fraction radially outward through the outer shell.

29. The hydrocyclone of claim 9, wherein the inner shell and the outer shell are cylindrical in the region of the transition zone, and are shaped in a region below the transition zone as truncated cones tapering in a direction away from the inlet.

30. The hydrocyclone of claim 10, wherein the inlet means is circular in cross-section, and wherein a transition means is provided connectingly between the inlet means and an entry point into the annular space wherein the cross-section of a path of flow of the input stream is changed from circular to essentially rectangular, wherein the length of the rectangular cross- section parallel to the axis of the two shells is greater than its width.

31. The hydrocyclone of claim 30, wherein the cross-section of the path of flow of the input stream is changed from circular to essentially square to essentially rectangular.

32. The hydrocyclone of claim 10, wherein a tangentially oriented inlet means leads into a transition zone of the annular space, and an outlet means communicating with the annular space, wherein the inner shell and the outer shell are cylindrical in the region of the transition zone, and are shaped in a region below the transition zone as truncated cones tapering in a direction away from the inlet.

33. The hydrocyclone of claim 10, further comprising passage means in at least one of the inner shell and the outer shell permitting, respectively, passage of a light fraction radially inward through the inner shell and passage of a heavy fraction radially outward through the outer shell.

34. The hydrocyclone of claim 18, further comprising passage means in at least one of the inner shell and the outer shell permitting, respectively, passage of a light fraction radially inward through the inner shell and passage of a heavy fraction radially outward through the outer shell.

35. The hydrocyclone of claim 18, wherein the inlet means is circular in cross-section, and wherein a transition means is provided connectingly between the inlet means and an entry point into the annular space wherein the cross-section of a path of flow of the input stream is changed from circular to essentially rectangular, wherein the length of the rectangular cross- section parallel to the axis of the two shells is greater than its width.

36. The hydrocyclone of claim 35, wherein the cross-section of the path of flow of the input stream is changed from circular to essentially square to essentially rectangular.

37. A hydrocyclone for effecting separation of a combined phase input stream, comprising an inner shell residing concentrically within an outer shell, the two shells forming an annular space therebetween of constant width, a tangentially oriented inlet means leading into the annular space, and an outlet means communicating with the annular space, wherein the inlet means is circular in cross-section, and wherein a transition means is provided connectingly between the inlet means and an entry point into the annular space wherein the cross-section of a path of flow of the input stream is changed from circular to essentially rectangular, wherein the length of the rectangular cross-section parallel to the axis of the two shells is greater than its width, and wherein a ratio of the constant width of the annular space with respect to the inside diameter of the inner shell is less than about 0.40.