Emulsions containing water-soluble acid retarding agents and methods of making and using

Patent metadata

Field	Value
Publication number	US-12559668-B2
Application number	US-202418886189-A
Country	US
Kind code	B2
Filing date	Sep 16, 2024
Priority date	Sep 3, 2015
Publication date	Feb 24, 2026
Grant date	Feb 24, 2026

Abstract

A multi-phase aqueous composition includes a surfactant; a first phase comprising water, an acid, and a water-soluble acid retarding agent; and a second phase selected from the group consisting of an immiscible organic phase, a gas, and combinations thereof. Further described are methods of making and using such compositions.

First claim

What is claimed is:

1 . A treatment fluid, comprising:
an emulsion of an aqueous phase and an organic phase, the emulsion stabilized using a cationic surfactant; wherein the aqueous phase comprises an acid and a water-soluble acid retarding agent; wherein the acid is present in the treatment fluid in an amount up to 45.7 wt. % based on a total weight of the treatment fluid and includes hydrogen chloride (HCl); wherein the water-soluble acid retarding agent comprises 19 wt. % of magnesium chloride (MgCl 2 ) based on the total weight of the treatment fluid; and wherein an acid retardation factor of the treatment fluid is between 3 to 11 at 70° C.

2 . The treatment fluid of claim 1 , wherein the aqueous phase of the emulsion is about 70% by volume, and the organic phase of the emulsion is about 30% by volume.

3 . The treatment fluid of claim 1 , wherein the emulsion is stabilized using the cationic surfactant, and the cationic surfactant comprises the structure [RNXYZ}+A−;
wherein R is an alkyl chain of 10 to 18 carbons; X, Y, and Z are each selected from the group consisting of methyl, ethyl, hydroxyethyl, and benzyl; and A is an anion selected from the group consisting of fluoride, chloride, bromide, iodide, acetate, sulfate, alkylsulfonate, and arylsulfonate.

4 . The treatment fluid of claim 1 , wherein the organic phase comprises alkanes, cycloalkanes, aromatic compounds, heteroaromatic compounds, or combinations thereof.

5 . The treatment fluid of claim 1 , wherein a water concentration of the emulsion is less than or equal to 80 wt.% based on a total weight of the emulsion.

6 . The treatment fluid of claim 1 , wherein the treatment fluid is an oilfield treatment fluid.

7 . The treatment fluid of claim 6 , wherein the oilfield treatment fluid comprises a matrix acidizing fluid, a wellbore cleanup fluid, a pickling fluid, a near wellbore damage cleanup fluid, a surfactant treatment fluid, or an unviscosified fracture fluid.

8 . A method comprising:
providing a treatment fluid, comprising:
an emulsion of an aqueous phase and an organic phase, the emulsion stabilized using a cationic surfactant;
wherein the aqueous phase comprises an acid and a water-soluble acid retarding agent;
wherein the acid is present in the treatment fluid in a non-zero amount up to 45.7 wt.% based on a total weight of the treatment fluid and includes hydrogen chloride (HCl);
wherein the water-soluble acid retarding agent comprises 19 wt.% of magnesium chloride (MgCl 2 ) based on the total weight of the treatment fluid; and
wherein an acid retardation factor of the treatment fluid is between 3 to 11 at 70° C.; and
treating a subterranean formation fluidly coupled to a wellbore with the treatment fluid.

9 . The method of claim 8 , wherein the emulsion is stabilized using the cationic surfactant, and the cationic surfactant comprises the structure [RNXYZ}+A−;
wherein R is an alkyl chain of 10 to 18 carbons; X, Y, and Z are each selected from the group consisting of methyl, ethyl, hydroxyethyl, and benzyl; and A is an anion selected from the group consisting of fluoride, chloride, bromide, iodide, acetate, sulfate, alkylsulfonate, and arylsulfonate.

10 . The method of claim 8 , wherein the aqueous phase of the emulsion is about 70% by volume, and the organic phase of the emulsion is about 30% by volume.

11 . The method of claim 8 , wherein the organic phase comprises alkanes, cycloalkanes, aromatic compounds, heteroaromatic compounds, or combinations thereof.

Assignees

• Schlumberger Technology Corp

Inventors

• Daeffler Christopher
• Panga Mohan Kanaka Raju

Classifications

• E21B41/02

  in situ inhibition of corrosion in boreholes or wells · CPC title

• C09K8/74

  combined with additives added for specific purposes · CPC title

• C09K8/703

  Foams · CPC title

• E21B43/27

  by use of eroding chemicals, e.g. acids · CPC title

• C09K8/66 Primary

  Compositions based on water or polar solvents (C09K8/64 takes precedence) · CPC title