US 11,739,254 B2
Methods for use in oil and gas operations
Dennis A. Alexis, Richmond, TX (US); Gayani Pinnawala Arachchilage, Katy, TX (US); Varadarajan Dwarakanath, Houston, TX (US); Do Hoon Kim, Katy, TX (US); Taimur Malik, Houston, TX (US); Gregory A. Winslow, Houston, TX (US); and Aaron Wilhelm, Fulsher, TX (US)
Assigned to CHEVRON U.S.A. INC., San Ramon, CA (US); and CHEVRON ORONITE COMPANY LLC, San Ramon, CA (US)
Filed by Chevron U.S.A. Inc., San Ramon, CA (US); and Chevron Oronite Company LLC, San Ramon, CA (US)
Filed on May 17, 2021, as Appl. No. 17/321,993.
Application 17/321,993 is a continuation of application No. 16/262,216, filed on Jan. 30, 2019, granted, now 11,008,502.
Claims priority of provisional application 62/624,092, filed on Jan. 30, 2018.
Prior Publication US 2022/0098470 A1, Mar. 31, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. E21B 43/26 (2006.01); C09K 8/584 (2006.01); C09K 8/588 (2006.01); C09K 8/68 (2006.01); F17D 1/16 (2006.01); C09K 8/88 (2006.01); C09K 8/52 (2006.01); C08L 33/26 (2006.01); C09K 8/60 (2006.01); C08K 5/09 (2006.01); C08K 5/37 (2006.01)
CPC C09K 8/584 (2013.01) [C08L 33/26 (2013.01); C09K 8/52 (2013.01); C09K 8/588 (2013.01); C09K 8/602 (2013.01); C09K 8/68 (2013.01); C09K 8/88 (2013.01); E21B 43/26 (2013.01); F17D 1/16 (2013.01); C08K 5/09 (2013.01); C08K 5/37 (2013.01); C09K 2208/28 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method for performing an enhanced oil recovery (EOR) operation, comprising:
(a) providing a subsurface reservoir containing hydrocarbons therewithin;
(b) providing a wellbore in fluid communication with the subsurface reservoir;
(c) preparing an aqueous surfactant-polymer solution; and
(d) injecting the aqueous surfactant-polymer solution through the wellbore into the subsurface reservoir;
wherein preparing an aqueous surfactant-polymer solution, comprises:
providing a concentrated liquid surfactant composition comprising:
(a) a surfactant package in an amount of from 0.2% to 98% by weight, based on the total weight of the concentrated liquid surfactant composition;
(b) a co-solvent in an amount of from greater than 0% to 95% by weight, based on the total weight of the concentrated liquid surfactant composition; and
(c) a liquid polymer (LP) composition in an amount of from 0.1% to 60% by weight, based on the total weight of the concentrated liquid surfactant composition;
wherein the concentrated liquid surfactant composition has a total water content of from 0.5% to 20% by weight, based on the total weight of the concentrated liquid surfactant composition; and
combining the concentrated liquid surfactant composition with an aqueous fluid in a single stage mixing process to provide the aqueous surfactant-polymer solution,
wherein the single stage mixing process comprises applying a specific mixing energy of at least 0.10 kJ/kg to the concentrated liquid surfactant composition and the aqueous fluid; and
wherein the aqueous surfactant-polymer solution comprises a polymer concentration of from 50 to 15,000 ppm.