Polymeric microspheres as degradable fluid loss additives in oilfield applications

• US 7,748,452 B2
• Filed: 02/19/2008
• Issued: 07/06/2010
• Est. Priority Date: 02/19/2008
• Status: Expired due to Fees

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Vatry, Christelle, Drochon, Bruno, Sullivan, Philip F, Tustin, Gary John, Dessinges, Marie Noelle, Kubala, Gregory
• Primary Examiner(s): Bates; Zakiya W.
• Application Number:
  US12/033,630
• Publication Number:
  US 20090205829A1
• Time in Patent Office: 868 Days
• Field of Search: None
• US Class Current: 166/279
• CPC Class Codes: C09K 8/426 for plugging
• CPC Class Codes: C09K 8/516 characterised by their form or by the form of their components, e.g. encapsulated material

Abstract

A method of plugging a fracture in a subterranean formation which includes placing into the fracture a composition comprising microspheres or microbeads, wherein the microspheres are created by surface crosslinking of droplets in a water-in-water emulsion. Such microspheres may form a filter cake in the formation. The microspheres may include a chemical agent to be released when the microspheres dissolve.

Claims

1. A method of plugging a fracture in a formation by placing into the fracture a composition comprising microspheres or microbeads, wherein the microspheres were created by surface crosslinking of droplets in a water-in-water emulsion.

2. A method according to claim 1 wherein the microspheres release at least one chemical agent when dissolved.

3. A method according to claim 1 wherein the microspheres comprise a crosslinked polysaccharide polymer.

4. A method according to claim 1 wherein the microspheres comprise alginate.

5. A method according to claim 1 wherein the microspheres comprise a void wherein said void contains least one chemical agent.

6. A method according to claim 5 wherein the chemical agent is released when the microspheres dissolve.

7. A method according to claim 5 wherein the chemical agent is a breaker.

8. A method according to claim 1 wherein the composition is a cement composition.

9. A method according to claim 8 wherein the microspheres comprise a void wherein said void contains least one chemical agent.

10. A method according to claim 9 wherein the microsphere release said at least one chemical agent when the microspheres dissolve.

11. A method according to claim 10 wherein the at least one chemical agent is a breaker.

12. A method according to claim 11 wherein the fluid further comprises a polymeric gelling agent, and wherein the microspheres dissolve, and the crosslinking agent used to form the microspheres subsequently causes delayed crosslinking of the polymeric gelling agent.

13. A method according to claim 1 wherein the composition is an aqueous treatment composition.

14. A method of forming a filter cake in a subterranean formation, said filter cake comprising crosslinked microspheres, wherein the microspheres are created by surface crosslinking of droplets in a water-in-water emulsion.

15. A method according to claim 14 wherein the microspheres comprise a crosslinked polysaccharide polymer.

16. A method according to claim 14 wherein the microspheres comprise alginate.

17. A method according to claim 14 wherein said filter cake is substantially destroyed when said microspheres dissolve.

18. A method according to claim 14 wherein the composition is a cement composition.

19. A method according to claim 14 wherein the composition is an aqueous treatment composition.

20. A method of treatment of a subterranean formation comprising providing a treatment fluid comprising a carrier fluid and microspheres, wherein the microspheres are formed by surface crosslinking of droplets in a water-in-water emulsion.

21. A method according to claim 20 wherein the microspheres release at least one chemical agent when dissolved.

22. A method according to claim 20 wherein the microspheres comprise a crosslinked polysaccharide polymer.

23. A method according to claim 20 wherein the microspheres comprise alginate.

24. A method according to claim 20 wherein the microspheres comprise a void wherein said void contains least one chemical agent.

25. A method according to claim 24 wherein the chemical agent is released when the microspheres dissolve.

26. A method according to claim 25 wherein the chemical agent is a breaker.