# US 11,299,664 B2 · Foaming mixtures and methods of use thereof

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,299,664 B2
- Document ID: US11299664B2
- Status: Granted
- Kind: B2
- Application number: 17/006,122
- Filed: 2020-08-28
- Published: 2020-12-17
- Granted: 2022-04-12
- Earliest claimed: 2019-02-05
- Assignees: Saudi Arabian Oil Company
- Applicants: Saudi Arabian Oil Company
- Inventors: Mustafa Alkhowaildi; Zuhair Yousef; Sunil Kokal
- Web page: https://patentgrep.com/patent/US11299664B2

## CPC

- C09K 8/594: Compositions used in combination with injected gas {, e.g. CO2 orcarbonated gas}(C09K8/592 takes precedence)
- C07C 69/587: Monocarboxylic acid esters having at least two carbon-to-carbon double bonds
- C09K 8/584: characterised by the use of specific surfactants
- E21B 43/16: Enhanced recovery methods for obtaining hydrocarbons
- E21B 43/164: {Injecting CO2 or carbonated water (in combination with organic material C09K8/594)}
- C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C07C: ACYCLIC OR CARBOCYCLIC COMPOUNDS
- E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS

## Abstract

Fluids injected into a carbonate reservoir formation during Enhanced Oil Recovery (EOR) may include a foaming mixture that includes a zwitterionic surfactant, an omega-3-acid ethyl ester, and aqueous salt solution. The omega-3-acid ethyl ester may include eicosapentaenoic acid ethyl ester, docosahexaenoic acid ethyl ester, or combinations thereof. The foaming mixtures may be incorporated into methods for enhancing hydrocarbon recovery in a carbonate reservoir formation. The methods may include introducing the foaming mixture to the carbonate reservoir formation such that any hydrocarbon present in the carbonate reservoir formation is displaced by the foaming mixture and is recoverable from the carbonate reservoir formation.

## Claims

### Claim 1

A foaming mixture comprising a zwitterionic surfactant, an omega-3-acid ethyl ester, and aqueous salt solution, in which the omega-3-acid ethyl ester comprises eicosapentaenoic acid ethyl ester and docosahexaenoic acid ethyl ester, wherein the aqueous salt solution comprises from 30,000 ppm to 60,000 ppm of at least one metal salt.

### Claim 2 (depends on 1)

The foaming mixture of claim 1, wherein the zwitterionic surfactant comprises a zwitterionic alkyl amine.

### Claim 3 (depends on 2)

The foaming mixture of claim 2, wherein the zwitterionic alkyl amine is selected from lauramine oxide, cocamine oxide, cocamidopropyl betaine, myristamine oxide, or combinations thereof.

### Claim 4 (depends on 2)

The foaming mixture of claim 2, wherein the zwitterionic surfactant comprises from 15 wt. % to 40 wt. % of the zwitterionic alkyl amine, based on the total weight of the zwitterionic surfactant.

### Claim 5 (depends on 1)

The foaming mixture of claim 1, wherein the zwitterionic surfactant comprises an alcohol.

### Claim 6 (depends on 5)

The foaming mixture of claim 5, wherein the alcohol comprises isopropanol.

### Claim 7 (depends on 5)

The foaming mixture of claim 5, wherein the zwitterionic surfactant comprises from 10 wt. % to 30 wt. % of the alcohol, based on the total weight of the zwitterionic surfactant.

### Claim 8 (depends on 1)

The foaming mixture of claim 1, wherein the omega-3-acid ethyl ester comprises greater than 50 wt. % eicosapentaenoic acid ethyl ester, based on the total weight of the omega-3-acid ethyl ester.

### Claim 9 (depends on 1)

The foaming mixture of claim 1, wherein the omega-3-acid ethyl ester comprises greater than 50 wt. % eicosapentaenoic acid ethyl ester, based on the total weight of the omega-3-acid ethyl ester, with the balance of the omega-3-acid ethyl comprising docosahexaenoic acid ethyl ester.

### Claim 10 (depends on 1)

The foaming mixture of claim 1, wherein the aqueous salt solution comprises untreated seawater.

### Claim 11 (depends on 1)

The foaming mixture of claim 1, wherein the foaming mixture comprises from 0.5 wt. % to 10 wt. % of the zwitterionic surfactant, based on the total weight of the foaming mixture.

### Claim 12 (depends on 11)

The foaming mixture of claim 11, wherein the foaming mixture comprises from 5.0 wt. % to 15 wt. % of the omega-3-acid ethyl ester, based on the total weight of the foaming mixture.

### Claim 13 (depends on 11)

The foaming mixture of claim 11, wherein the foaming mixture comprises from 75 wt. % to 95 wt. % of the aqueous salt solution, based on the total weight of the foaming mixture.

### Claim 14 (depends on 1)

The foaming mixture of claim 1, wherein the foaming mixture has a pH ranging from 6.0 to 9.5.

### Claim 15

A foaming mixture, comprising:
from 0.5 wt. % to 10 wt. % of a zwitterionic surfactant, based on the total weight of the foaming mixture;
from 5.0 wt. % to 15 wt. % of an omega-3-acid ethyl ester, based on the total weight of the foaming mixture; and
from 75 wt. % to 95 wt. % of an aqueous salt solution, based on the total weight of the foaming mixture, wherein the aqueous salt solution comprises from 30,000 ppm to 60,000 ppm of at least one metal salt;
wherein the omega-3-acid ethyl ester comprises eicosapentaenoic acid ethyl ester and docosahexaenoic acid ethyl ester.

### Claim 16 (depends on 15)

The foaming mixture of claim 15, wherein the zwitterionic surfactant comprises:
from 15 wt. % to 40 wt. % of a zwitterionic alkyl amine, based on the total weight of the zwitterionic surfactant zwitterionic alkyl amine; and
from 10 wt. % to 30 wt. % of an alcohol, based on the total weight of the zwitterionic surfactant zwitterionic alkyl amine.

### Claim 17 (depends on 16)

The foaming mixture of claim 16, wherein the alcohol comprises isopropanol.