Enhancing Emulsion Stability

• US 20110024128A1
• Filed: 02/11/2009
• Published: 02/03/2011
• Est. Priority Date: 03/20/2008
• Status: Active Grant

• Current Assignee: Robert D. Kaminsky
• Original Assignee: Robert D. Kaminsky
• Inventors: Kaminsky, Robert D.
• Granted Patent: US 8,592,351 B2
• Time in Patent Office: Days
• US Class Current: 166/369
• CPC Class Codes: B01F 23/4105 Methods of emulsifying
• CPC Class Codes: B01F 25/45 Mixers in which the materials to be mixed are pressed together through orifices or interstitial spaces, e.g. between beads B01F25/44 takes precedence
• CPC Class Codes: B01F 25/4523 the components being pressed through sieves, screens or meshes which obstruct the whole diameter of the tube
• CPC Class Codes: B01F 25/50 Circulation mixers, e.g. wherein at least part of the mixture is discharged from and reintroduced into a receptacle
• CPC Class Codes: B01F 27/272 with means for moving the materials to be mixed axially between the surfaces of the rotor and the stator, e.g. the stator rotor system formed by conical or cylindrical surfaces
• CPC Class Codes: B01F 33/8212 with moving and non-moving stirring devices

Abstract

The present invention is directed to methods and apparatuses for generating an emulsion with enhanced stability. The methods include forming a stressed emulsion fluid using a high-shear mixer and stressing the emulsion by microporous flow, aging, heating, or another process, and reshearing the stressed emulsion fluid. The process may be repeated for enhanced stability. In some embodiments the generated emulsion may be used in hydrocarbon recovery operations. Optionally, the emulsion may include surfactants or solid microparticles for additional stability enhancement.

Claims

1. A method of producing a macroemulsion, comprising:

forming a macroemulsion having a continuous phase component and an internal phase component; and

improving the stability of the macroemulsion, comprising;

mechanically stressing the macroemulsion to rupture at least a portion of the internal phase component to produce a stressed macroemulsion having a surviving macroemulsion portion and a broken-out internal phase portion; and

shearing the surviving macroemulsion with at least a portion of the broken-out internal phase portion to form an improved stability macroemulsion.

4. The method of claim 1, wherein the at least a portion of the broken-out internal phase portion is substantially all of the broken-out internal phase portion of the stressed macroemulsion.

5. The method of claim 1, wherein the macroemulsion is an oil-in-water emulsion or a water-in-oil emulsion.

6. The method of claim 1, further comprising injecting the improved stability macroemulsion into a subterranean formation.

8. The method of claim 1, wherein the internal phase component comprises droplets and the volume fraction of droplets in the macroemulsion is greater than 50 volume percent.

9. The method of claim 1, wherein the internal phase component comprises droplets and the volume fraction of droplets in the macroemulsion is about 60 volume percent.

10. The method of claim 1, further comprising adding solid microparticles to the macroemulsion to enhance emulsion stability.

11. The method of claim 1, wherein the stressing step comprises passing the macroemulsion through a microfilter.

12. The method of claim 11, wherein the microfilter comprises sintered metal, natural porous rock, or unconsolidated granular material.

13. The method of claim 12, wherein the microfilter has an average pore throat size of less than about 20 microns.

14. The method of claim 12, wherein the microfilter has an average pore throat size of less than about 7 microns.

19. The method of claim 1, wherein the step of improving the stability of the macroemulsion by stressing and reshearing the macroemulsion is repeated at least once.

21. The method of claim 19, further comprising adding water during the at least one repetition.

22. The method of claim 6, further comprising using the improved stability macroemulsion as a displacement fluid to displace viscous hydrocarbons from the subterranean formation.

24. The method of claim 6, further comprising using the improved stability macroemulsion as a plugging fluid to block or divert fluid flow in the subterranean formation.

26. The method of claim 1, further comprising heating the macroemulsion prior to or during the stressing step.

28. The method of claim 4, further comprising adding a diluent to the oil portion of the macroemulsion.

29. The method of claim 28, wherein the diluent is a hydrocarbon liquid or a gaseous substance.

37. A method of producing hydrocarbons, comprising:

generating an improved stability emulsion utilizing the method of claim 1;

injecting the improved stability emulsion into a subterranean formation; and

using the improved stability emulsion as a drive fluid to displace hydrocarbons from the subterranean formation.

2. A method of producing a macroemulsion, comprising:

forming a macroemulsion having a continuous phase component and an internal phase component; and

improving the stability of the macroemulsion, comprising a once-through process of;

stressing the macroemulsion to rupture at least a portion of the internal phase component to produce a stressed macroemulsion having a surviving macroemulsion portion and a broken-out internal phase portion; and

shearing the surviving macroemulsion with at least a portion of the broken-out internal phase portion to form an improved stability macroemulsion.

15. The method of claim 2, wherein the stressing step comprises a step selected from the group consisting of passing the macroemulsion through a microfilter, aging the macroemulsion, heating the macroemulsion, and any combination thereof.

17. The method of claim 15, wherein the macroemulsion is aged for from about three minutes to about 30 minutes prior to shearing the surviving macroemulsion with at least a portion of the broken-out internal phase portion.

38. A method of producing hydrocarbons, comprising:

generating an improved stability emulsion utilizing the method of claim 2;

injecting the improved stability emulsion into a subterranean formation; and

using the improved stability emulsion as a drive fluid to displace hydrocarbons from the subterranean formation.

40. The method of claim 2, further comprising injecting the improved stability macroemulsion into a subterranean formation.

41. The method of claim 2, wherein the internal phase component comprises droplets and the volume fraction of droplets in the macroemulsion is greater than 50 volume percent.

43. The method of claim 2, further comprising adding solid microparticles to the macroemulsion to enhance emulsion stability.

46. The method of claim 2, further comprising heating the macroemulsion prior to or during the stressing step.

3. A method of producing a macroemulsion, comprising:

forming a first macroemulsion having a continuous phase component and an internal phase component;

mixing the first macroemulsion with a recycled emulsion to form a second macroemulsion; and

improving the stability of the second macroemulsion, comprising the steps of;

a) stressing the second macroemulsion to rupture at least a portion of the internal phase component to produce a stressed macroemulsion having a surviving macroemulsion portion and a broken-out internal phase portion;

b) shearing the surviving macroemulsion with at least a portion of the broken-out internal phase portion to form an improved stability macroemulsion; and

c) separating the improved stability macroemulsion into the recycle macroemulsion and a final stabilized macroemulsion.

7. The method of claim 3, wherein the final stabilized macroemulsion is injected into a subterranean formation.

16. The method of claim 3, wherein the stressing step comprises a step selected from the group consisting of passing the second macroemulsion through a microfilter, aging the second macroemulsion, heating the second macroemulsion, and any combination thereof.

18. The method of claim 16, wherein the second macroemulsion is aged for from about three minutes to about 30 minutes prior to shearing the surviving macroemulsion with at least a portion of the broken-out internal phase portion.

20. The method of claim 3, wherein the step of improving the stability of the second macroemulsion by stressing and reshearing the second macroemulsion is repeated at least once.

23. The method of claim 7, further comprising using the final stabilized macroemulsion as a displacement fluid to displace viscous hydrocarbons from the subterranean formation

25. The method of claim 7, further comprising using the final stabilized macroemulsion as a plugging fluid to block or divert fluid flow in the subterranean formation.

27. The method of claim 3, further comprising heating the second macroemulsion prior to or during the stressing step.

39. A method of producing hydrocarbons, comprising:

generating an improved stability emulsion utilizing the method of claim 3;

injecting the improved stability emulsion into a subterranean formation; and

using the improved stability emulsion as a drive fluid to displace hydrocarbons from the subterranean formation.

42. The method of claim 3, wherein the internal phase component comprises droplets and the volume fraction of droplets in the macroemulsion is greater than 50 volume percent.

44. The method of claim 3, further comprising adding solid microparticles to the macroemulsion to enhance emulsion stability.

45. The method of claim 20, further comprising adding water during the at least one repetition.

30. An apparatus for generating an emulsion, comprising:

a high-shear mixer configured to mix an oil component and a water component to form a macroemulsion fluid;

a stressing unit configured to mechanically stress the macroemulsion fluid to rupture at least a portion of the internal phase component to produce a stressed macroemulsion having a surviving macroemulsion portion and a broken-out internal phase portion, wherein the stressing unit is operatively attached to the high-shear mixer; and

a mixing unit configured to shear the stressed macroemulsion fluid to form at least a final stabilized macroemulsion fluid, wherein the mixing unit is operatively attached to the stressing unit.

31. The apparatus of claim 30, wherein the stressing unit is a microfilter.

32. The apparatus of claim 30, wherein the mixing unit is the high-shear mixer and wherein a portion of the stressed macroemulsion is recycled to the high-shear mixer.

33. The apparatus of claim 30, comprising a first and second stressing unit and a first and second mixing unit, wherein:

the macroemulsion fluid is formed in the high-shear mixer, the macroemulsion fluid is stressed in the first stressing unit, then mixed in the first mixing unit, then stressed in the second stressing unit, then mixed in the second mixing unit to produce the final stabilized macroemulsion fluid.

34. The apparatus of claim 33, wherein the second stressing unit is a microfilter, a heating unit, or an aging unit.

35. The apparatus of claim 33, wherein the entire water component is added in the high-shear mixer.

36. The apparatus of claim 33, wherein a first portion of the water component is added in the high-shear mixer, a second portion of the water component is added in the first mixing unit, and a third portion of the water component is added in the second mixing unit.