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:
Mar. 22, 1994
Filed:
Nov. 16, 1992
Nizar F Djabbarah, Richardson, TX (US);
Ralph V Garling, Irving, TX (US);
Mobil Oil Corporation, Fairfax, VA (US);
Abstract
The invention is a foam method for improving conformance during a steam flood or carbon dioxide flood in a subterranean, oil-containing formation penetrated by at least one injection well and at least one production well. In a steam flood oil recovery process, sweep efficiency is improved by injecting steam until steam breakthrough occurs at the production well after which a mixture of steam, a noncondensible gas, and an aqueous surfactant-starch solution is injected into the formation. The aqueous surfactant-starch solution forms a stable foam with the formation oil at formation conditions that reduce the permeability of the highly permeable steam swept zones thereby diverting the steam to other portions of the formation containing unswept oil. The starch is used as a partial substitute for the surfactant to improve the cost of the foam-forming mixture without reducing its effectiveness in increasing sweep efficiency.