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:
Nov. 18, 2014
Filed:
Feb. 10, 2010
Guillaume Degre, Lamartine Talence, FR;
Mikel Morvan, Jacques Ellul Pessac, FR;
Guillaume Degre, Lamartine Talence, FR;
Mikel Morvan, Jacques Ellul Pessac, FR;
Rhodia Operations, Aubervilliers, FR;
Abstract
The present invention relates to a method for the assisted recovery of crude oil from an underground formation, comprising: a) injecting, via at least one injection means in contact with the underground formation containing the crude oil, a liquid containing a mixture of at least: i) a salty aqueous medium, ii) a mixture of two zwitterionic viscosising surfactants or a mixture of two populations of said surfactants having a bimodal characteristic of the narrow distribution of Ri groups as defined below, in a weight content of between 1 and 0.05 wt %, preferably between 0.5 and 0.1 wt %, and more preferably between 0.4 and 0.15 wt %, such that the liquid has an oil/water interface tension of about 10 mN/m (milinewton per meter) or less as measured at room temperature (25° C.) and a viscosity of about 3 cPs or more as measured at a temperature of 80° C. for a shearing gradient of 10 s, and corresponding to formula (1) where the two Ri radicals of the two surfactants or surfactant populations have a difference in the number of carbon atoms thereof that is at least greater than or equal to 4. The method comprises using at least one production means located at a different location than that at which the liquid or the polymer has been fed in order to recover the liquid containing the crude oil.