Foamed well cement compositions, additives and methods
AssigneeHalliburton Energy Services, Inc.
InventorsJiten Chatterji, David D. Onan, Roger S. Cromwell, Bobby J. King
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Abstract
The present invention relates to improved foamed well cement compositions, additives and methods. The additives, which foam and stabilize a cement slurry containing freshwater or saltwater, are basically comprised of an aqueous solution of an alpha-olefinic sulfonate surfactant and a betaine surfactant.
Claims22
A foamed cement composition for cementing a well comprising;
- a hydraulic cement;
- sufficient water to form a pumpable slurry;
- sufficient gas to form a foam;
- and
- an effective amount of an additive for foaming and stabilizing said slurry consisting essentially of about two parts by weight of an alpha-olefinic sulfonate surfactant having the formula
- H(CH.sub.2).sub.n --CH.dbd.CH--(CH.sub.2).sub.m SO.sub.3 Na
- wherein n and m are integers in the range of from about 6 to about 16, and about 1 part by weight of a betaine surfactant having the formula
- R--CONHCH.sub.2 CH.sub.2 CH.sub.2 N.sup.+ (CH.sub.3).sub.2 CH.sub.2 CO.sub.2.sup.-
- wherein R is a radical selected from the group of decyl, cetyl, oleyl, lauryl and cocoyl.
A single universal additive for foaming and stabilizing a cement slurry containing freshwater or salt water comprising an aqueous solution of an alpha-olefinic sulfonate surfactant having the formula
- H(CH.sub.2).sub.n --CH.dbd.CH--(CH.sub.2).sub.m SO.sub.3 Na
- wherein n and m are integers in the range from about 6 to about 16 and wherein said alpha-olefinic sulfonate surfactant is present in an amount in the range of from about 15% to about 25% by weight of said aqueous solution, and a betaine surfactant having the formula
- R--CONHCH.sub.2 CH.sub.2 CH.sub.2 N.sup.+ (CH.sub.3).sub.2 CH.sub.2 CO.sub.2.sup.-
- wherein R is a radical selected from the group of decyl, cetyl, oleyl, lauryl and cocoyl and wherein said betaine surfactant is present in an amount in the range of from about 8% to about 12% by weight of said aqueous solution.
A method of cementing a subterranean zone penetrated by a well bore comprising the steps of:
- (a) forming a foamed cement composition comprised of hydraulic cement, sufficient water to form a pumpable slurry, sufficient gas to form a foam and an effective amount of an additive for foaming and stabilizing said slurry consisting essentially of about 2 parts by weight of an alpha-olefinic sulfonate surfactant having the formula
- H(CH.sub.2).sub.n --CH.dbd.CH--(CH.sub.2).sub.m SO.sub.3 Na
- wherein n and m are integers in the range of from about 6 to about 16, and about 1 part by weight of a betaine surfactant having the formula
- R--CONHCH.sub.2 CH.sub.2 CH.sub.2 N.sup.+ (CH.sub.3).sub.2 CH.sub.2 CO.sub.2.sup.-
- wherein R is a radical selected from the group of decyl, cetyl, oleyl, lauryl and cocoyl;
- (b) pumping said foamed cement composition into said subterranean zone by way of said well bore;
- and
- (c) allowing said foamed cement composition to set into a hard impermeable mass.
Dependencies are inferred from the claim text.