Blocking composition for use in subterranean formation

• US 6,192,986 B1
• Filed: 02/18/1999
• Issued: 02/27/2001
• Est. Priority Date: 09/18/1996
• Status: Expired due to Term

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Urlwin-Smith, Phillip Lance
• Primary Examiner(s): Bagnell, David
• Assistant Examiner(s): Dougherty, Jennifer R.
• Application Number:
  US09/242,552
• Time in Patent Office: 740 Days
• Field of Search: 507/224, 507/225, 507/239, 166/294, 166/295, 166/300, 166/305.1
• US Class Current: 166/295
• CPC Class Codes: C09K 8/512 containing cross-linking agents

Abstract

A polymer composition for pumping downhole to gel in a subterranean formation comprises a water-soluble copolymer of (i) at least one non-acidic ethylenically unsaturated polar monomer and (ii) at least one copolymerisable ethylenically unsaturated ester; and an organic gelling agent therefor.

Claims

1. A composition for use in a subterranean formation, which composition comprises a water-soluble copolymer comprising

(i) at least one non-acidic ethylenically unsaturated polar monomer;

and

(ii) at least one coplymerisable ethylenically unsaturated ester;

and at least one organic gelling agent, characterized in that the organic gelling agent is a polyalkyleneimine, a poly-functional aliphatic amine, an aralkylamine or a heteroaralkylamine.

2. A composition according to claim 1, wherein the poly-functional aliphatic amine is a polyalkylenepolyamine.

3. A composition according to claim 2, wherein the polyalkylenepolyamine is a polyethylene- or polypropylene-polyamine.

4. A composition according to claim 1, wherein the polyakyleneimine is a polymerised ethyleneimine or propyleneimine.

5. A composition according to claim 1, wherein the said heteroaralkylamine contains at least one heteroatom.

6. A composition according to any of claims 1 to 5, wherein the copolymer comprises from one to three polar monomers (i) and from 1 to 3 unsaturated esters (ii).

7. A composition according to any of claims 1 to 5, wherein the ester is formed from a hydroxyl compound and an ethylenically unsaturated carboxylic acid selected from acrylic, methacrylic, crotonic and cinnamic acids.

8. A composition according to claim 7, wherein the hydroxyl compound is an alcohol of formula ROH where R is a C1-30 alkyl, alkenyl, cycloalkyl, aryl or aralkyl group, is a hydroxyl, ether or thio ether substituted hydrocarbyl group.

9. A composition according to any of claims 1 to 5, wherein the ethylenically unsaturated ester is an alkyl or aralkyl acrylate in which the alkyl group is a C1 to 10 alkyl group and the aralkyl group is a C1 to 5 alkyl substituted aryl group.

10. A composition according to any of claims 1 to 5, wherein the ethylenically unsaturated polar monomer is an amide of an unsaturated carboxylic acid.

11. A composition according to claim 10, wherein the ethylenically unsaturated polar monomer is acrylamide.

12. A composition according to any of claims 1 to 5, wherein the copolymer contains from 5-15% mol of structural units from said ester and 95-85% mol of structural units from said polar monomer.

13. A composition according to any of claims 1 to 5, wherein the copolymer is a regular or random copolymer or a graft copolymer.

14. A composition according to claim 13, wherein the coploymer is a graft copolymer in which ester units are grafted onto a polyacrylamide.

15. A composition according to any of claims 1 to 5, wherein the copolymer is soluble in water to an extent of at least 10 g/l.

16. A composition according to any of claims 1 to 5, wherein the copolymer has a weight average molecular weight of at least 50,000.

17. A composition according to claim 16, wherein the copolymer has a weight average molecular weight of 1-10 million.

18. A composition according to any of claims 1 to 5, wherein the copolymer and the gelling agent are in aqueous solution.

19. A method of conformance control of a subterranean reservoir, which comprises:

(a) injecting into a formation an aqueous solution of a composition as claimed in any of claims 1 to 5;

(b) allowing the solution to flow through at least one permeable zone in said formation;

(c) allowing the composition to gel.