Enhanced oil recovery compositions and methods thereof

Patent metadata

Field	Value
Publication number	US-10851629-B2
Application number	US-201916421909-A
Country	US
Kind code	B2
Filing date	May 24, 2019
Priority date	Sep 2, 2015
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

Additional oil recovery is obtained from a reservoir with a composition comprising at least a coupling solvent typically employed in waterborne coating compositions. Provided herein are embodiments of methods of recovering hydrocarbons using at least one coupling solvent, such as an oxygenated coupling solvent. The coupling solvent increases the mutual solubility with water at the injection temperature to facilitate the mixing and injection, particularly with an optional co-solvent. The coupling solvent helps mitigate formation plugging and improve performance when injected into a formation, as the solvent mixture moves from being miscible in the injection field water to being miscible in the reservoir oil, mobilizing the reservoir oil to increase oil recovery.

First claim

The invention claimed is:

1. A method to recover hydrocarbons from a reservoir, the method comprising:
forming an injection stream comprising a brine, a coupling solvent, and a co-solvent or a second coupling solvent for injection into the reservoir, the injection stream having a phase inversion temperature that is greater than a temperature of the injection stream prior to injection into the reservoir and that is less than a reservoir temperature such that the coupling solvent and the co-solvent or the second coupling solvent form a miscible mixture in a single phase with the brine prior to injection into the reservoir, wherein:
the co-solvent or the second coupling solvent are different from the coupling solvent such that if the coupling solvent comprises ethers, glycol ethers, glycol ether esters, or any combination thereof, then the co-solvent or the second coupling solvent comprise ketones, esters, lactams, cyclic ureas, alcohols, aromatic hydrocarbons, aliphatic hydrocarbons, nitroalkanes, halocarbons, alkoxy ethoxyethanol compounds, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, or any combination thereof; and

injecting the injection stream into the reservoir, wherein at least a portion of the coupling solvent separates from the brine as the temperature of the injection stream increases to the reservoir temperature and achieves the phase inversion temperature of the injection stream, and the at least the portion of the coupling solvent becomes miscible with hydrocarbons in the reservoir to displace the hydrocarbons toward a production well.

2. The method of claim 1 , wherein a concentration of the coupling solvent is determined such that the phase inversion temperature of the injection stream is modified to within 10° C. of the reservoir temperature prior to injection into the reservoir.

3. The method of claim 1 , wherein the coupling solvent increases a mutual solubility with the brine at the temperature of the injection stream prior to injection into the reservoir.

4. The method of claim 1 , wherein the coupling solvent includes at least one oxygen atom.

5. The method of claim 1 , wherein the coupling solvent comprises ketones, esters, or any combination thereof, and wherein the co-solvent or the second coupling solvent comprise ketones, esters, ethers, glycol ethers, glycol ether esters, lactams, cyclic ureas, alcohols, aromatic hydrocarbons, aliphatic hydrocarbons, nitroalkanes, halocarbons, alkoxy ethoxyethanol compounds, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, or any combination thereof.

6. The method of claim 1 , wherein the coupling solvent comprises an alkyl ether of mono and di ethylene glycol where the alkyl group comprises one to eight carbon atoms.

7. The method of claim 1 , wherein the injection stream comprises a concentration having 2-25 wt. % of the coupling solvent.

8. The method of claim 1 , wherein the co-solvent or the second coupling solvent modifies the phase inversion temperature of the injection stream.

9. The method of claim 8 , wherein the co-solvent or the second coupling solvent modifies the phase inversion temperature of the injection stream to within 10° C. of the reservoir temperature prior to injection into the reservoir.

10. The method of claim 8 , wherein the co-solvent or the second coupling solvent modifies the range of coupling solvent to brine ratios where phase separation occurs by at least 10%.

11. The method of claim 8 , wherein the co-solvent or the second coupling solvent is provided in a weight ratio of the coupling solvent to the co-solvent or the second coupling solvent ranging from 1:20 to 20:1.

12. The method of claim 8 , wherein the coupling solvent has a phase equilibria defining phase boundaries and the co-solvent or the second coupling solvent shifts the phase boundaries of the phase equilibria to customize the injection stream for the reservoir temperature.

13. The method of claim 1 , further comprising recovering at least a portion of the coupling solvent from the brine and the displaced hydrocarbons produced from the production well.

14. The method of claim 1 , wherein the injection stream further comprises a polymer.

15. A method to recover hydrocarbons from a reservoir, the method comprising:
forming an injection stream comprising a brine, a coupling solvent, and a co-solvent or a second coupling solvent for injection into the reservoir, wherein concentrations of the coupling solvent and the co-solvent or the second coupling solvent are determined such that the coupling solvent and the co-solvent or the second coupling solvent form a miscible mixture in a single phase with the brine prior to injection into the reservoir, wherein:
the coupling solvent comprises ketones, esters, ethers, glycol ethers, glycol ether esters, or any combination thereof; and
the co-solvent or the second coupling solvent comprise ketones, esters, ethers, glycol ethers, glycol ether esters, lactams, cyclic ureas, alcohols, aromatic hydrocarbons, aliphatic hydrocarbons, nitroalkanes, halocarbons, alkoxy ethoxyethanol compounds, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, or any combination thereof; and
the co-solvent or the second coupling solvent are different from the coupling solvent such that if the coupling solvent comprises ethers, glycol ethers, glycol ether esters, or any combination thereof, then the co-solvent or the second coupling solvent comprise ketones, esters, lactams, cyclic ureas, alcohols, aromatic hydrocarbons, aliphatic hydrocarbons, nitroalkanes, halocarbons, alkoxy ethoxyethanol compounds, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, or any combination thereof; and

injecting the injection stream into the reservoir, wherein at least a portion of the coupling solvent separates from the brine as a temperature of the injection stream increases to a reservoir temperature and achieves a phase inversion temperature of the injection stream, and the at least the portion of the coupling solvent becomes miscible with hydrocarbons in the reservoir to displace the hydrocarbons toward a production well.

16. The method of claim 15 , wherein the co-solvent or the second coupling solvent is added at a sufficient concentration to modify the phase inversion temperature of the injection stream to within 10° C. of the reservoir temperature prior to injection into the reservoir.

17. The method of claim 15 , wherein the co-solvent or the second coupling solvent modifies the range of coupling solvent to brine ratios where phase separation occurs by at least 10%.

18. The method of claim 15 , wherein the injection stream comprises a concentration having 2-25 wt. % of the coupling solvent.

19. The method of claim 15 , wherein the co-solvent or the second coupling solvent is provided in a weight ratio of the coupling solvent to the co-solvent or the second coupling solvent ranging from 1:20 to 20:1.

20. The method of claim 15 , wherein the coupling solvent has a phase equilibria defining phase boundaries and the co-solvent or the second coupling solvent shifts the phase boundaries of the phase equilibria to customize the injection stream for the reservoir temperature.

Assignees

• Chevron Usa Inc

Inventors

• Dwarakanath Varadarajan
• Shong Robert G
• Winslow Gregory A
• Malik Taimur
• Solano Marlon

Classifications

• C09K8/58 Primary

  Compositions for enhanced recovery methods for obtaining hydrocarbons, i.e. for improving the mobility of the oil, e.g. displacing fluids · CPC title

• C08L2201/54

  Aqueous solutions or dispersions · CPC title

• C08L5/00

  Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00 · CPC title

• C09K8/584

  characterised by the use of specific surfactants · CPC title

• E21B43/162 Primary

  Injecting fluid from longitudinally spaced locations in injection well · CPC title