US 11,753,582 B2
Injection fluids comprising an anionic surfactant for treating unconventional formations
Dustin L. Walker, Dallas, TX (US); Gayani W. Pinnawala, Houston, TX (US); Nabijan Nizamidin, Emeryville, CA (US); Varadarajan Dwarakanath, Houston, TX (US); Guo-Qing Tang, Mountain View, CA (US); Dustin J. Lowry, Pinole, CA (US); Tetsuo Art Inouye, Sebastopol, CA (US); and Taimur Malik, Houston, TX (US)
Assigned to CHEVRON U.S.A. INC., San Ramon, CA (US)
Appl. No. 16/635,733
Filed by CHEVRON U.S.A. INC., San Ramon, CA (US)
PCT Filed Jul. 31, 2018, PCT No. PCT/US2018/044707
§ 371(c)(1), (2) Date Jan. 31, 2020,
PCT Pub. No. WO2019/028083, PCT Pub. Date Feb. 7, 2019.
Claims priority of provisional application 62/538,883, filed on Jul. 31, 2017.
Prior Publication US 2021/0095184 A1, Apr. 1, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. C09K 8/60 (2006.01); E21B 47/11 (2012.01); C09K 8/86 (2006.01); E21B 43/27 (2006.01); C09K 8/68 (2006.01); C09K 8/74 (2006.01); C09K 8/80 (2006.01); E21B 43/267 (2006.01)
CPC C09K 8/604 (2013.01) [C09K 8/602 (2013.01); C09K 8/68 (2013.01); C09K 8/74 (2013.01); C09K 8/80 (2013.01); C09K 8/86 (2013.01); E21B 43/267 (2013.01); E21B 43/27 (2020.05); E21B 47/11 (2020.05); C09K 2208/10 (2013.01); C09K 2208/12 (2013.01); C09K 2208/26 (2013.01); C09K 2208/28 (2013.01); C09K 2208/32 (2013.01)] 20 Claims
OG exemplary drawing
 
19. A method for treating an unconventional subterranean formation with a fluid, comprising:
providing an aqueous-based injection fluid for treating the unconventional subterranean formation, the unconventional subterranean formation having a rock matrix with an average pore size less than 0.1 micrometers;
adding a single-phase liquid surfactant package comprising an anionic surfactant to the aqueous-based injection fluid to form a low particle size injection fluid; and
introducing the low particle size injection fluid into the rock matrix of the unconventional subterranean formation,
wherein the low particle size injection fluid is aqueous stable and has a maximum particle size of less than 0.1 micrometers in diameter particle size distribution measurement when measured at a temperature and salinity of the unconventional subterranean formation.