Patent ID: 11879095
Assignee: KEMIRA OYJ
Field: Basic materials chemistry (Chemistry)
Classification: CPC C  E | IPC C  E

Claim 0:
1. A method of increasing the viscosity in an oil or gas containing aqueous environment, which method comprises introducing at least one polymer into said oil or gas containing aqueous environment comprising a temperature of about 55-140° C., wherein said at least one polymer comprises labile monomer units, and further wherein:
said at least one polymer comprises no charge prior to introduction into the oil or gas containing aqueous environment or has an initial anionic charge of less than 25 mole percent measured prior to introduction into the oil or gas containing aqueous environment;
said at least one polymer is introduced into the oil or gas containing aqueous environment as an aqueous solution or aqueous composition;
said at least one polymer is not cross-linked when introduced into the oil or gas containing aqueous environment and further does not become cross-linked in the oil or gas containing aqueous environment;
said at least one polymer, when present in the oil or gas containing aqueous environment for a duration of 1-100 months, increases in charge over said duration, thereby providing for an increase in viscosity of said aqueous solution or aqueous composition comprising said at least one polymer which is present in said oil or gas containing aqueous environment, wherein said increase in viscosity occurs as a result of the labile monomer units in said at least one polymer breaking or hydrolyzing by reaction with water comprised in the oil or gas containing aqueous environment, thereby forming one or more carboxylates;
said at least one polymer is introduced into the oil or gas containing aqueous environment during an enhanced oil or gas recovery process as a polymer flood; and
whereby the resultant increase in viscosity of said aqueous solution or aqueous composition comprising said at least one polymer provides for an increase in oil or gas recovery from said oil or gas containing aqueous environment.