Polyelectrolyte complexes for oil and gas applications

• US 20080058229A1
• Filed: 09/05/2006
• Published: 03/06/2008
• Est. Priority Date: 09/05/2006
• Status: Active Grant

• Current Assignee: University of Kansas
• Original Assignee: University of Kansas
• Inventors: Berkland, Cory, Willhite, G. Paul, Cordova, Mary, Liang, Jenn-Tai
• Granted Patent: US 8,183,184 B2
• Time in Patent Office: Days
• US Class Current: 507/211
• CPC Class Codes: C09K 2208/10 Nanoparticle-containing well treatment fluids
• CPC Class Codes: C09K 2208/20 Hydrogen sulfide elimination
• CPC Class Codes: C09K 2208/22 Hydrates inhibition by using well treatment fluids containing inhibitors of hydrate formers
• CPC Class Codes: C09K 2208/24 Bacteria or enzyme containing gel breakers
• CPC Class Codes: C09K 2208/26 Gel breakers other than bacteria or enzymes
• CPC Class Codes: C09K 8/516 characterised by their form or by the form of their components, e.g. encapsulated material
• CPC Class Codes: C09K 8/536 characterised by their form or by the form of their components, e.g. encapsulated material
• CPC Class Codes: C09K 8/54 Compositions for in situ inhibition of corrosion in boreholes or wells
• CPC Class Codes: C09K 8/584 characterised by the use of specific surfactants
• CPC Class Codes: C09K 8/60 Compositions for stimulating production by acting on the underground formation
• CPC Class Codes: C09K 8/706 Encapsulated breakers
• CPC Class Codes: C09K 8/92 characterised by their form or by the form of their components, e.g. encapsulated material C09K8/70 takes precedence
• CPC Class Codes: Y10S 507/902 Controlled release agent

Abstract

A polyelectrolyte complex for the controlled release of an oil and gas field chemical selected from the group consisting of (a) a gel-forming or cross-linking agent, (b) a scale inhibitor, (c) a corrosion inhibitor, (d) an inhibitor of asphaltene or wax deposition, (e) a hydrogen sulfide scavenger, (f) a hydrate inhibitor, (g) a breaking agent, and a surfactant.

Claims

1. A composition for controlling the release of an oil and gas field chemical comprising:

a polyanion and a polycation forming a polyelectrolyte complex, and an oil and gas field chemical associated with said polyelectrolyte complex.

2. The composition of claim 1 wherein said oil and gas field chemical is selected from the group consisting of (a) a gel-forming or cross-linking agent, (b) a scale inhibitor, (c) a corrosion inhibitor, (d) an inhibitor of asphaltene or wax deposition, (e) a hydrogen sulfide scavenger, (f) a hydrate inhibitor, (g) a breaking agent, and (h) a surfactant.

3. The composition of claim 1 wherein said polycation is selected from the group consisting of chitosan, polyethylenimine, poly-L-lysine and said polyanion comprises dextran sulfate.

4. The composition of claim 1 wherein said oil and gas field chemical is a gel-forming agent, and wherein said gel-forming agent is a complexed chromium compound selected from the group consisting of chromium nitrate, chromium chloride, chromium citrate, chromium acetate, chromium propionate.

5. The composition of claim 1 further comprising a monovalent or bivalent cation selected from the group consisting of sodium ion or calcium ion.

6. The composition of claim 1 further comprising an anion selected from the group consisting of triphosphate ion, chloride ion, or sulfate ion.

7. The composition of claim 1 wherein said oil and gas field chemical is an enzymatic breaker selected from the group consisting of amylase, amyloglucosidase, invertase, maltase, cellulose, pectinase, and hemicellulase.

8. The composition of claim 1 wherein said oil and gas field chemical is a scale inhibitor comprising polyacrylic acid.

9. The composition of claim 1 wherein said oil and gas field chemical is a corrosion inhibitor comprising benzyldimethyltetradecylammonium chloride.

10. The composition of claim 1 wherein said oil and gas field chemical is a surfactant comprising sodium dodecyl sulfate.

11. The composition of claim 1 wherein said polyelectrolyte complex comprises a nanoparticle with a particle size of about 100 to 300 nm in diameter.

12. A method for producing a composition for the delayed release of an oil and gas field chemical comprising:

mixing a polyanion, a polycation, and an oil and gas field chemical together in solution;

ceasing mixing to form a polyelectrolyte complex comprising said polyanion and said polycation and said oil and gas field chemical associated with said polyelectrolyte complex.

13. The method of claim 12 wherein said polyanion and polycation are first mixed together separately prior to mixing said polyanion, polycation, and oil and gas field chemical.

14. The method of claim 12 wherein said polycation and oil and gas field chemical are first mixed together separately prior to mixing said polyanion, polycation, and oil and gas field chemical.

15. The method of claim 12 wherein said polyanion and oil and gas field chemical are first mixed together separately prior to mixing said polyanion, polycation, and oil and gas field chemical.

16. The method of claim 12 further comprising dialyzing said polyelectrolyte complex solution to isolate a polyelectrolyte nanoparticle having said oil and gas field chemical associated therewith.

17. The method of claim 12 wherein said oil and gas field chemical is selected from the group consisting of (a) a gel-forming or cross-linking agent, (b) a scale inhibitor, (c) a corrosion inhibitor, (d) an inhibitor of asphaltene or wax deposition, (e) a hydrogen sulfide scavenger, (f) a hydrate inhibitor, (g) a breaking agent, and (h) a surfactant.

18. The method of claim 12 wherein said oil and gas field chemical comprises a multivalent metallic cross-linking compound or organic cross-linking agent.

19. The method of claim 12 wherein said oil and gas field chemical is a cross-linking agent comprising a chromium containing compound.

20. The method of claim 12 wherein said polycation is selected from the group consisting of chitosan, polyethylenimine, poly-L-lysine and said polyanion comprises dextran sulfate.

21. The method of claim 12 wherein said oil and gas field chemical is a gel-forming agent, and wherein said gel-forming agent is a complexed chromium compound selected from the group consisting of chromium nitrate, chromium chloride, chromium citrate, chromium acetate, chromium propionate.

22. The method of claim 12 further comprising the step of adding a cation selected from the group consisting of sodium ion or calcium ion.

23. The method of claim 12 further comprising the step of adding an anion selected from the group consisting of triphosphate ion, chloride ion, or sulfate ion.

24. The method of claim 12 wherein said oil and gas field chemical is an enzymatic breaker selected from the group consisting of amylases, amyloglucosidase, invertase, maltase, cellulose, pectinase, and hemicellulase.

25. The method of claim 12 wherein said oil and gas field chemical is a scale inhibitor comprising polyacrylic acid.

26. The method of claim 12 wherein said oil and gas field chemical is a corrosion inhibitor comprising benzyldimethyltetradecylammonium chloride.

27. The method of claim 12 wherein said oil and gas field chemical is a surfactant comprising sodium dodecyl sulfate.

28. The method of claim 12 wherein said complex comprises a nanoparticle ranging from about 100 to 300 nm in diameter.

29. A method for controlling or delaying the release of an oil and gas field chemical comprising:

providing a polyelectrolyte complex associated with said oil and gas field chemical;

introducing said polyelectrolyte complex associated with said oil and gas field chemical into a target area.

30. The method of claim 29 wherein said target area is an oil well, and said oil and gas field chemical is selected from the group consisting of (a) a gel-forming or cross-linking agent, (b) a scale inhibitor, (c) a corrosion inhibitor, (d) an inhibitor of asphaltene or wax deposition, (e) a hydrogen sulfide scavenger, (f) a hydrate inhibitor, (g) a breaking agent, and (h) a surfactant.