Oil recovery by waterflooding employing a biopolymer-surfactant system
Patent 4008766 Issued on February 22, 1977. Estimated Expiration Date: February 22, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
166/270.1, Injecting a composition including a surfactant or cosurfactant507/213, Polysaccharide is a xanthan (e.g., scleroglucans, etc.)507/244, Oxygen is attached directly or indirectly to carbon by nonionic bonding507/261, Organic component contains ether linkage (e.g., PEG ether, etc.)507/262, Organic component contains a carbocyclic group507/936Flooding the formation
A process for the recovery of oil from subterranean oil reservoirs by waterflooding employing a multicomponent anionic-nonionic surfactant system in combination with a Xanthomonas polysaccharide thickening agent. The surfactant system and polysaccharide provide for an enhanced thickening action in the injected aqueous liquid at relatively low shear rates. The anionic surfactant employed is an amide-linked sulfonate and the nonionic component is a polyethylene oxide type surfactant.
Other References
Foster, W. R., "A Low-Tension Waterflooding Process", Journal of Petroleum Technology, Feb. 1973, vol. 25, pp. 205-210
McCutcheon, J. W., "Surfactants Listed...", Reprint from "Soap & Chemical Specialties" Dec. 1957, Jan.-Apr., 1958, p. 30
February 22, 1994. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
