DIVERSION BY COMBINING DISSOLVABLE AND DEGRADABLE PARTICLES AND FIBERS

• US 20110226479A1
• Filed: 01/27/2011
• Published: 09/22/2011
• Est. Priority Date: 04/15/2008
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Dardis, Michael A., Simon, David Ryan, Ariza, Ricardo, Tippel, Philipp, Morris, Elizabeth W.A., Davis, Darrell P., Swaren, Jason, Boney, Curtis L., Rees, Desmond E., Lassek, John
• Granted Patent: US 9,212,535 B2
• Time in Patent Office: Days
• US Class Current: 166/305.1
• CPC Class Codes: C09K 2208/08 Fiber-containing well treatment fluids
• CPC Class Codes: E21B 33/138 Plastering the borehole wall; Injecting into the formation

Abstract

In downhole treatments in the oilfield, ball sealers seated in perforations may not fully seal and may leak fluid through gaps and asperities between the balls and the perforations. A method is given for improving the sealing of ball sealers in perforations by adding a sealing agent that forms a plug in the gaps and severely restricts or eliminates fluid flow. The sealing agent is preferably degradable or soluble, malleable fibers slightly larger than the gaps. Optionally, the particles may be non-degradable, rigid, of different shapes, and smaller than the gaps but able to bridge them. Mixtures of sealing agents may be used. The sealing agent may be added with the ball sealers, after the ball sealers, or both.

Claims

1. A method of using a fluid within a subterranean formation, comprising:

forming a fluid comprising fibers and particles;

introducing perforation sealers into the fluid;

introducing the fluid into the subterranean formation;

forming a seal in a perforation in the formation; and

allowing the fibers or particles or both to degrade.

2. The method of claim 1, further comprising controlling a rate of fluid introduction using a pressure observation.

3. The method of claim 1, further comprising controlling the concentration of fibers and particles using a pressure observation.

4. The method of claim 1, further comprising controlling the volume of perforation sealers introduced into the fluid using a pressure observation.

5. The method of claim 1, wherein the allowing the degrading comprises a time for shut-in the well.

6. The method of claim 1, further comprising initiating flow-back without allowing fibers or particles or both introduced during the treatment to flow to an upper surface of the formation.

7. The method of claim 1, wherein the forming a fluid and introducing the sealers occurs before introducing the fluid into the formation.

8. The method of claim 1, wherein introducing the fluid into the formation occurs before the introducing the perforation sealers.

9. The method of claim 1, wherein introducing the perforation sealers occurs before introducing the fluid into the subterranean formation.

10. The method of claim 1, wherein the concentration of the particles is higher than the concentration of the fibers.

11. A method of using a fluid within a subterranean formation, comprising:

forming a fluid comprising fibers and particles;

introducing perforation sealers into the fluid;

introducing the fluid into the subterranean formation;

observing a pressure measurement of the subterranean formation; and

allowing the fibers or particles or both to degrade.

12. The method of claim 11, further comprising controlling a rate of fluid introduction using the pressure measurement.

13. The method of claim 11, further comprising controlling the concentration of fibers and particles using the pressure measurement.

14. The method of claim 11, further comprising controlling the volume of perforation sealers introduced into the fluid using the pressure measurement.

15. The method of claim 11, wherein the allowing the degrading comprises a time for shut-in the well.

16. The method of claim 11, further comprising initiating flow-back without allowing fibers or particles or both introduced during the treatment to flow to an upper surface of the formation.

17. The method of claim 11, wherein the forming a fluid and introducing the sealers occurs before introducing the fluid into the formation.

18. The method of claim 11, wherein introducing the fluid into the formation occurs before the introducing the perforation sealers.

19. The method of claim 11, wherein introducing the perforation sealers occurs before introducing the fluid into the subterranean formation.

20. The method of claim 11, wherein the concentration of the particles is higher than the concentration of the fibers.