Injection well cleaning fluids and related methods

Patent metadata

Field	Value
Publication number	US-11661543-B2
Application number	US-202117167307-A
Country	US
Kind code	B2
Filing date	Feb 4, 2021
Priority date	Feb 4, 2021
Publication date	May 30, 2023
Grant date	May 30, 2023

Abstract

Methods can include introducing a cleaning fluid into a near-wellbore zone of an injection well penetrating a subterranean formation, wherein the cleaning fluid includes: 0.5 wt % to about 5 wt % of a surfactant blend comprising an alkoxy carbonate surfactant and an internal olefin sulfonate surfactant; salt water having a total dissolved solids (TDS) of about 15,000 mg/L or greater; and 0 wt % to about 0.05 wt % of an organic acid; and dispersing a hydrocarbon from the near-wellbore zone in the cleaning fluid. Compositions for cleaning a near-wellbore zone of a subterranean formation can include 0.5 wt % to about 5 wt % of a surfactant blend comprising an alkoxy carbonate surfactant and an internal olefin sulfonate surfactant; salt water having a total dissolved solids (TDS) of about 15,000 mg/L or greater; and 0 wt % to about 0.05 wt % of an organic acid.

First claim

The invention claimed is:

1. A method comprising:
introducing a cleaning fluid into a near-wellbore zone of an injection well penetrating a subterranean formation, wherein the cleaning fluid comprises:
0.5 wt % to about 5 wt % of a surfactant blend comprising an alkoxy carbonate surfactant and an internal olefin sulfonate surfactant;
salt water having a total dissolved solids (TDS) of about 15,000 mg/L or greater; and
0 wt % to about 0.05 wt % of an organic acid;

introducing an acidizing fluid into the near-wellbore zone after injecting the cleaning fluid, wherein the acidizing fluid comprises water and a sufficient amount of an acid to cause the acidizing fluid to have a pH of about 1.5 to about 5.5; and
dispersing a hydrocarbon from the near-wellbore zone in the cleaning fluid.

2. The method of claim 1 further comprising:
shutting in the cleaning fluid in the near-wellbore zone.

3. The method of claim 1 further comprising:
shutting in the cleaning fluid in the near-wellbore zone; and
shutting in the acidizing fluid in the near-wellbore zone.

4. The method of claim 1 , wherein the injection well has a bottom hole temperature of 150° C. or less.

5. The method of claim 1 , wherein the alkoxy carbonate surfactant comprises a surfactant according to Formula I

where R 1 is a C 8 -C 24 alkyl, a C 8 -C 24 cyclo-alkyl, or a C 8 -C 24 aryl-alkyl
where n is an integer from 1 to 30.

6. The method of claim 1 , wherein the alkoxy carbonate surfactant comprises a surfactant according to Formula II

where R 2 is a C 8 -C 24 alkyl, a C 8 -C 24 cyclo-alkyl, or a C 8 -C 24 aryl-alkyl
where m is an integer from 1 to 30.

7. The method of claim 1 , wherein the internal olefin sulfonate surfactant comprises a surfactant according to Formula III

where R 3 is a C 1 -C 20 alkyl, a C 1 -C 20 cyclo-alkyl, or a C 1 -C 20 aryl-alkyl
where R 4 is a C 1 -C 20 alkyl, a C 1 -C 20 cyclo-alkyl, or a C 1 -C 20 aryl-alkyl
where X + is a cation of hydrogen, lithium, sodium, or potassium.

8. The method of claim 1 , wherein the internal olefin sulfonate surfactant comprises a surfactant according to Formula I

where R 5 is a C 1 -C 20 alkyl, a C 1 -C 20 cyclo-alkyl, or a C 1 -C 20 aryl-alkyl
where R 6 is a C 1 -C 20 alkyl, a C 1 -C 20 cyclo-alkyl, or a C 1 -C 20 aryl-alkyl
where R 7 is a C 1 -C 20 alkyl, a C 1 -C 20 cyclo-alkyl, or a C 1 -C 20 aryl-alkyl
where X + is a cation of hydrogen, lithium, sodium, or potassium.

9. The method of claim 1 , wherein a weight ratio of the alkoxy carbonate surfactant to the internal olefin sulfonate surfactant is about 80:20 to about 20:80.

10. A method comprising:
introducing a cleaning fluid into a near-wellbore zone of an injection well penetrating a subterranean formation, wherein the cleaning fluid comprises:
0.5 wt % to about 5 wt % of a surfactant blend comprising an alkoxy carbonate surfactant and an internal olefin sulfonate surfactant;
salt water having a total dissolved solids (TDS) of about 15,000 mg/L or greater;
an acidizing fluid comprising water and an acid selected from the group consisting of hydrofluoric acid, hydrochloric acid, acetic acid, formic acid, phosphoric acid, and combinations thereof, where the acid is present in a sufficient amount to cause the acidizing fluid to have a pH of about 1.5 to about 5.5; and

dispersing hydrocarbon from the near-wellbore zone into the cleaning fluid.

11. The method of claim 10 where the acid is an organic acid and the organic acid is present at about 0.001 wt % to about 0.05 wt %.

12. A method comprising:
introducing a cleaning fluid into a near-wellbore zone of an injection well penetrating a subterranean formation, wherein the cleaning fluid comprises:
0.5 wt % to about 5 wt % of a surfactant blend comprising an alkoxy carbonate surfactant and an internal olefin sulfonate surfactant;
salt water having a total dissolved solids (TDS) of about 15,000 mg/L or greater; and

introducing an acidizing fluid into the near-wellbore zone after injecting the cleaning fluid, wherein the acidizing fluid comprises water and a sufficient amount of an acid to cause the acidizing fluid to have a pH of about 1.5 to about 5.5, where the acid in the acidizing fluid is selected from the group consisting of hydrofluoric acid, hydrochloric acid, acetic acid, formic acid, phosphoric acid, and combinations thereof; and
dispersing a hydrocarbon from the near-wellbore zone in the cleaning fluid.

13. The method of claim 12 where the acidizing fluid has a pH of about 1.9 to about 4.8.

Assignees

• Baker Hughes Oilfield Operations Llc

Inventors

• Quintero Lirio
• Russek Jeffrey A

Classifications

• C09K8/528 Primary

  inorganic depositions, e.g. sulfates or carbonates · CPC title

• E21B37/06

  using chemical means for preventing or limiting {, e.g. eliminating,} the deposition of paraffins or like substances · CPC title

• C09K8/74

  combined with additives added for specific purposes · CPC title