Injection fluids comprising an anionic surfactant for treating unconventional formations

Patent metadata

Field	Value
Publication number	US-12435262-B2
Application number	US-202318464691-A
Country	US
Kind code	B2
Filing date	Sep 11, 2023
Priority date	Jul 31, 2017
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

Described herein are compositions and methods that stabilize an injection fluid when exposed to reservoir conditions, reducing formation damage and increasing the amount of hydrocarbon recovered. Specifically, the formulation is a single-phase liquid surfactant package which comprises an anionic surfactant and optionally one or more secondary surfactants.

First claim

What is claimed is:

1. A method for treating an unconventional subterranean formation with a fluid, comprising:
(a) combining a single-phase liquid surfactant package comprising a primary surfactant with an aqueous-based injection fluid to form a low particle size injection fluid; and
(b) introducing the low particle size injection fluid into the unconventional subterranean formation;
wherein the primary surfactant comprises C10-C16 disulfonate; and
wherein the low particle size injection fluid is aqueous stable and has a maximum particle size of less than 0.1 micrometers in diameter in particle size distribution measurements performed at a temperature and salinity of the unconventional subterranean formation.

2. The method of claim 1 , wherein the low particle size injection fluid further comprises a proppant, and wherein the maximum particle size of less than 0.1 micrometers is exclusive of the proppant.

3. The method of claim 1 , wherein the primary surfactant comprises from 10% to 90% by weight of the single-phase liquid surfactant package; and
wherein the primary surfactant has a concentration within the low particle size injection fluid of less than 1% based on the total weight of the low particle size injection fluid.

4. The method of claim 1 , wherein the single-phase liquid surfactant package further comprises one or more secondary surfactants;
wherein the one or more secondary surfactants comprise a non-ionic surfactant, an anionic surfactant, a cationic surfactant, a zwitterionic surfactant, or any combination thereof.

5. The method of claim 4 , wherein the one or more secondary surfactants comprise an anionic surfactant,
wherein the anionic surfactant comprises a sulfonate, a disulfonate, a polysulfonate, a sulfate, a disulfate, a polysulfate, a sulfosuccinate, a disulfosuccinate, a polysulfosuccinate, a carboxylate, a dicarboxylate, a polycarboxylate, or any combination thereof,
wherein the anionic surfactant comprises a branched or unbranched C6-C32:PO(0-65):EO(0-100)-carboxylate, a branched or unbranched C6-C30:PO(30-40):EO(25-35)-carboxylate, a branched or unbranched C6-C12:PO(30-40):EO(25-35)-carboxylate, a branched or unbranched C6-C30:EO(8-30)-carboxylate, or any combination thereof;
a surfactant defined by the formula below

wherein
R 1 comprises a branched or unbranched, saturated or unsaturated, cyclic or non-cyclic, hydrophobic carbon chain having 6-32 carbon atoms and an oxygen atom linking R 1 and R 2 ;
R 2 comprises an alkoxylated chain comprising at least one oxide group selected from the group consisting of ethylene oxide, propylene oxide, butylene oxide, and combinations thereof; and
R 3 comprises a branched or unbranched hydrocarbon chain comprising 2-12 carbon atoms and from 2 to 5 carboxylate groups;
a C10-C30 internal olefin sulfonate, a C8-C30 alkyl benzene sulfonate (ABS), a sulfosuccinate surfactant, or any combination thereof; or
a surfactant defined by the formula below

wherein
R 4 is a branched or unbranched, saturated or unsaturated, cyclic or non-cyclic, hydrophobic carbon chain having 6-32 carbon atoms; and
M represents a counterion.

6. The method of claim 4 , wherein the one or more secondary surfactants comprise a non-ionic surfactant, and wherein the non-ionic surfactant comprises a branched or unbranched C6-C32:PO(0-65):EO(0-100), a branched or unbranched C6-C30:PO(30-40):EO(25-35), a branched or unbranched C6-C12:PO(30-40):EO(25-35), a branched or unbranched C12-C22:PO(0-65):EO(0-100), a branched or unbranched C12-C22:PO(30-40):EO(25-35), a branched or unbranched C6-C30:EO(8-30), an alkoxylated C12-C22 alcohol, or an alkoxylated C6-C16 Guerbet alcohol.

7. The method of claim 6 , wherein the non-ionic surfactant comprises a branched or unbranched C6-C30:PO(30-40):EO(25-35).

8. The method of claim 4 , wherein the one or more secondary surfactants comprise from 10% to 90% by weight of the single-phase liquid surfactant package; and
wherein the one or more secondary surfactants have a concentration within the low particle size injection fluid of less than 1%.

9. The method of claim 1 , wherein combination of the single-phase liquid surfactant package with the aqueous-based injection fluid lowers the particle size distribution of the aqueous-based injection fluid when measured at the temperature and salinity of the unconventional subterranean formation.

10. The method of claim 1 , wherein the low particle size injection fluid is a single-phase fluid.

11. The method of claim 1 , wherein the low particle size injection fluid has a mean particle size distribution of less than an average pore size of a rock matrix in the unconventional subterranean formation.

12. The method of claim 1 , wherein the low particle size injection fluid further comprises an acid.

13. The method of claim 1 , wherein the low particle size injection fluid further comprises a friction reducer, a gelling agent, a crosslinker, a breaker, a pH adjusting agent, a non-emulsifier agent, an iron control agent, a corrosion inhibitor, a scale inhibitor, a biocide, a clay stabilizing agent, a proppant, a wettability alteration chemical, or any combination thereof.

14. The method of claim 1 , wherein the single-phase liquid surfactant package further comprises one or more co-solvents, and
wherein the one or more co-solvents comprise a C1-C5 alcohol, an ethoxylated C1-C5 alcohol, or any combination thereof.

15. The method of claim 1 , wherein the aqueous-based injection fluid has a mean particle size distribution of greater than 10 micrometers prior to the addition of the single-phase liquid surfactant package.

16. The method of claim 1 , wherein the mean particle size distribution of the low particle size injection fluid is at least 10 micrometers smaller than a mean particle size distribution of the aqueous-based injection fluid.

17. The method of claim 1 , wherein the low particle size injection fluid precipitates out fewer solid particles than the aqueous-based injection fluid when introduced into the rock matrix.

18. The method of claim 1 , wherein the aqueous-based injection fluid comprises slickwater.

19. The method of claim 1 , wherein the aqueous-based injection fluid comprises at least 10% acid.

20. The method of claim 1 , wherein the method comprises a hydraulic fracturing operation.

21. The method of claim 1 , wherein the method comprises a formation stimulation operation.

22. 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 C10-C16 disulfonate 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; and
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.

23. A method for fracturing an

Assignees

• Chevron Usa Inc

Inventors

• Walker Dustin L
• Pinnawala Gayani W
• Nizamidin Nabijan
• Dwarakanath Varadarajan
• Tang Guo-Qing
• Lowry Dustin J
• Inouye Tetsuo Art
• Malik Taimur

Classifications

• E21B43/267

  reinforcing fractures by propping · CPC title

• C09K2208/32

  Anticorrosion additives · CPC title

• C09K2208/28

  Friction or drag reducing additives · CPC title

• C09K2208/26

  Gel breakers other than bacteria or enzymes · CPC title

• C09K2208/12

  Swell inhibition, i.e. using additives to drilling or well treatment fluids for inhibiting clay or shale swelling or disintegrating · CPC title