The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 16, 1988
Filed:
Aug. 05, 1987
Shigeto Suzuki, San Francisco, CA (US);
Chevron Research Company, San Francisco, CA (US);
Abstract
Oil recovery from a petroleum reservoir using a miscible gas, such as carbon dioxide, nitrogen or methane is enhanced by injecting a preformed stable foam into the reservoir. The foam composition is formed by an effective amount of an alpha olefin sulfonate (AOS) capable of forming a foam with water having a salt content similar to that in the reservoir and the miscible gas. Preferably, the alpha olefin sulfonates have from 8 to 24 carbon atoms. In a preferred form the AOS has on average a carbon content of less than about 12 carbon atoms in higher salt content brines and less than about 12 carbon atoms in lower salt content brines. Most preferably, in brines having a salt concentration of at least 10 weight percent, the AOS has on average about 10 carbon atoms; in brines having a salt concentration of from 2 to 10 weight percent the AOS has on average about 12 carbon atoms; and in brines having less than 2 weight percent salt and AOS has on average about 14 carbon atoms.