Salt of monochloroacetic acid with acid for delayed acidification in the oil field industry
AssigneeNouryon Chemicals International B.V.
InventorsAlbert Bokkers, Cornelis Elizabeth Johannus Van Lare, Cornelis Kooijman, Maria Antonieta Leon Matheus
Life of this patent
Estimating the term…
Abstract
A process for treating a subterranean earth formation by includes the step of introducing a buffered acidizing treatment fluid comprising a monovalent salt of monochloroacetic acid and at least one acid into the subterranean earth formation, wherein the pH of the buffered acidizing treatment fluid is from about 1.2 to about 5. The buffered acidizing treatment fluid itself includes the monovalent salt of monochloroacetic acid, the at least one acid and optionally an element to suppress salt precipitation.
Claims20
A process for treating a subterranean earth formation by introducing a buffered acidizing treatment fluid comprising a monovalent salt of monochloroacetic acid and at least one acid into the subterranean earth formation, wherein the pH of the buffered acidizing treatment fluid is from about 1.2 to about 5,
- wherein an element to suppress salt precipitation is also introduced into the subterranean earth formation and
- wherein the element to suppress salt precipitation is
- a chelating agent comprising at least one monovalent carboxylate salt group and furthermore comprises a carbon chain carrying at least five hydroxyl groups, and/or
- a scale inhibitor comprising a homopolymer of maleic acid or acrylic acid or a copolymer of maleic acid and acrylic acid, having a total number of carboxyl groups between 5 and 200, or a salt thereof, wherein the homopolymer or copolymer optionally comprises one or more phosphonic or sulfonic functional groups, and wherein total number of carboxyl groups is calculated from the weight average molecular weight of the homopolymer or copolymer as determined by size exclusion chromatography relative to polymethacrylic acid standards.
A process for treating a subterranean earth formation by introducing a buffered acidizing treatment fluid comprising a monovalent salt of monochloroacetic acid and at least one acid into the subterranean earth formation, wherein the pH of the buffered acidizing treatment fluid is from about 1.2 to about 5,
- wherein sodium gluconate is also introduced into the subterranean earth formation to suppress salt precipitation.
Dependencies are inferred from the claim text.