Methods and formulations for treating oil-containing porous media for oil recovery
Embodiments of the present disclosure generally relate to methods and formulations for enhanced oil recovery. In an embodiment, a method for treating oil-containing porous media for oil recovery includes introducing oil-containing porous media with a surfactant formulation described herein. Methods can be utilized for, e.g., wettability reversal or oil recovery. Surfactant formulations are also described.
1 . A method for treating oil-containing porous media for oil recovery, the method comprising:
introducing a surfactant formulation with a reservoir comprising oil-containing porous media, the oil-containing porous media being oil-wet prior to introducing with the surfactant formulation, the surfactant formulation comprising a surfactant A and a surfactant B:
wherein:
at least one surfactant A is present, and for each surfactant A present, each of R 1 , R 2 , and R 3 is methyl, R 4 is an alkyl group having 18 carbon atoms, and X is, independently, bromide or chloride; and
R5 of surfactant B is an alkyl group having 13 carbon atoms, and n of surfactant B is 18;
reversing a wettability of the oil-containing porous media from oil-wet towards water-wet by contacting the oil-containing porous media with the surfactant formulation; and
recovering oil from the oil-containing porous media.
2 . The method of claim 1 , wherein:
at least one surfactant A is present, and each surfactant A present is trimethyloctadecylammonium bromide or trimethyloctadecylammonium chloride.
3 . The method of claim 1 , wherein the method is performed in a tight oil reservoir, in a hydraulically fractured tight oil reservoir, or on a tight porous media.
4 . The method of claim 3 , wherein the method is performed in the hydraulically fractured tight oil reservoir, and the method further comprises, prior to the introducing operation:
creating fractures in rock formations in a tight oil reservoir; and
propping the fractures open by administering a proppant to form the hydraulically fractured tight oil reservoir.
5 . The method of claim 1 , wherein the oil-containing porous media is tight porous media.
6 . The method of claim 1 , wherein a volume ratio of surfactant B to surfactant A in the surfactant formulation is from about 50:50 to about 99:1.
7 . The method of claim 1 , wherein:
the surfactant formulation further comprises brine; and
the method further comprises lowering an interfacial tension between organic phase in the reservoir and aqueous phase present in the surfactant formulation by contacting the oil-containing porous media with the surfactant formulation.
8 . The method of claim 1 , wherein a volume ratio of surfactant B to surfactant A in the surfactant formulation is from about 70:30 to about 99:1.
9 . The method of claim 1 , wherein a total amount of surfactant A and surfactant B is from about 0.01 wt % to about 5 wt % based on a total weight of the surfactant formulation.
10 . The method of claim 1 , wherein:
the surfactant formulation further comprises brine; and
a total amount of surfactant A and surfactant B is from about 0.01 wt % to about 1 wt % based on a total weight of the surfactant formulation.
11 . The method of claim 10 , wherein the brine has a total dissolved solids content from about 100 ppm to about 5,000 ppm.
12 . The method of claim 10 , wherein the brine has a total dissolved solids content from about 10,000 ppm to about 100,000 ppm.
13 . The method of claim 10 , wherein the brine has a total dissolved solids content from about 50,000 ppm to about 1,000,000 ppm.