Foaming and silt suspending agent
AssigneeThe Dow Chemical Company
InventorJames L. Thompson
Life of this patent
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Abstract
A foaming and silt suspending agent is disclosed containing (A) at least one alkyltrimethylammonium chloride; (B) an amine oxide selected from the group consisting of bis-(2-hydroxyethyl) cocoamine oxide, dimethylhexadecylamine oxide, and dimethyl-hydrogenated tallowamine oxide; (C) an adduct of trimethyl-1-heptanol plus seven moles of ethylene oxide; and (D) a perfluorinated compound corresponding to the formula ##STR1## wherein A.sup.- is Cl.sup.-, I.sup.-, F.sup.- or Br.sup.-, preferably I.sup.-. The agent is particularly useful in a variety of aqueous based fluids of the type used in treating subterranean formations, including fluids containing other cationic additives such as certain acid inhibitors and clay stabilization agents which tend to impair the effectiveness of prior art agents.
Claims29
A composition suitable for imparting foaming and silt suspending properties to aqueous based fluids of the type suitable for use in treating subterranean formations, comprising a blend of:
- (A) at least one alkyltrimethylammonium chloride, wherein the alkyl chain length is from 8 to 18 carbon atoms and the mode alkyl chain length is 12 or 14 carbon atoms;
- (B) an amine oxide selected from the group consisting of bis-(2-hydroxyethyl) cocoamine oxide, dimethylhexadecylamine oxide, and dimethyl-hydrogenated tallowamine oxide;
- (C) an adduct of trimethyl-1-heptanol plus seven moles of ethylene oxide;
- and
- (D) a perfluorinated surfactant of the formula ##STR4## wherein A.sup.- is Cl.sup.-, F.sup.-, I.sup.-, or Br.sup.- ;
- wherein Components (A) and (B) are in a synergistic weight ratio to one another within the range of from about 99:1 to about 1:99;
- Components (C) and (D) are in a weight ratio to one another of from about 1:1 to about 40:1, and
- the combined amounts of Components (A) and (B) and the combined amounts of Components (C) and (D) in said composition are such that said composition can be diluted with an aqueous based fluid to yield a foamable fluid containing Components (A) and (B) in a combined concentration of from about 0.035 to about 0.5 weight percent and Components (C) and (D) in a combined concentration of from about 0.03 to about 0.1 weight percent.
A foam comprised of an aqueous based fluid, an inert gas, and a blend of
- (A) at least one alkyltrimethylammonium chloride, wherein the alkyl chain length is from 8 to 18 carbon atoms and the mode alkyl chain length is 12 or 14 carbon atoms;
- (B) an amine oxide selected from the group consisting of bis-(2-hydroxyethyl) cocoamine oxide, dimethylhexadecylamine oxide, and dimethyl-hydrogenated tallowamine oxide;
- (C) an adduct of trimethyl-1-heptanol plus seven moles of ethylene oxide;
- and
- (D) a perfluorinated surfactant of the formula ##STR5## wherein A.sup.- is Cl.sup.-, F.sup.-, I.sup.-, or Br.sup.- ;
- wherein Components (A) and (B) are in a synergistic weight ratio to one another within the range of from about 99:1 to about 1:99;
- Components (C) and (D) are in a weight ratio to one another of from about 1:1 to about 40:1,
- Components (A) and (B) are present in a combined amount of from about 0.035 to about 0.5 percent based on the weight of the liquid phase of said foam, and
- Components (C) and (D) are present in a combined amount of from about 0.03 to about 0.1 percent based on the weight of the liquid phase of said foam.
A method of treating a subterranean formation penetrated by a borehole, comprising injecting into the formation via the borehole, an aqueous based fluid mixed with an inert gas to form a foam and containing a foaming and silt suspending quantity of a blend of
- (A) at least one alkyltrimethylammonium chloride, wherein the alkyl chain length is from 8 to 18 carbon atoms and the mode alkyl chain length is 12 or 14 carbon atoms, and
- (B) an amine oxide selected from the group consisting of bis-(2-hydroxyethyl) cocoamine oxide, dimethylhexadecylamine oxide, and dimethyl-hydrogenated tallowamine oxide,
- (C) an adduct of trimethyl-1-heptanol plus seven moles of ethylene oxide, and
- (D) a perfluorinated surfactant of the formula ##STR6## wherein A.sup.- is Cl.sup.-, F.sup.-, I.sup.-, or Br.sup.-, wherein Components (A) and (B) are present in a synergistic weight ratio to one another of from about 99:1 to about 1:99 and together are present in a combined concentration of from about 0.035 to about 0.5 percent by weight of the aqueous based fluid, and
- Components (C) and (D) are present in a weight ratio to one another of from about 1:1 to about 40:1 and together are present in a combined concentration of from about 0.03 to about 0.1 percent by weight of the aqueous based fluid.
Dependencies are inferred from the claim text.