Oil-in-water stable, emulsified spacer fluids

Patent metadata

Field	Value
Publication number	US-10087356-B2
Application number	US-201314890849-A
Country	US
Kind code	B2
Filing date	Sep 19, 2013
Priority date	Sep 19, 2013
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

Some embodiments described herein provide a method comprising method comprising providing an oil-in-water emulsified spacer fluid comprising a binary surfactant mixture, solvent non-aqueous base fluid, and an aqueous base fluid, wherein the binary surfactant mixture comprises a surfactant and an amphiphilic co-surfactant, wherein the surfactant is present in an amount in the range of from about 0.5% to about 30% by weight of the oil-in-water emulsified spacer fluid and wherein the amphiphilic co-surfactant is present in an amount in the range of from about 0.5% to about 30% by weight of the oil-in-water emulsified spacer fluid, and introducing the oil-in-water emulsified spacer fluid into a subterranean formation comprising a residual non-aqueous fluid therein, wherein the binary surfactant mixture in the oil-in-water emulsified spacer fluid emulsifies at least a portion of the residual non-aqueous fluid.

First claim

The invention claimed is:

1. A method comprising:
providing an oil-in-water emulsified spacer fluid comprising a binary surfactant mixture, solvent non-aqueous base fluid, a weighting agent, and an aqueous base fluid,
wherein the binary surfactant mixture comprises a surfactant and an amphiphilic co-surfactant in a ratio of surfactant to amphiphilic co-surfactant in the range of about 1:2 to 2:1,
wherein the surfactant is a betaine and is present in an amount in the range of from about 0.5% to about 5% by weight of the oil-in-water emulsified spacer fluid and wherein the amphiphilic co-surfactant is present in an amount in the range of from about 0.5% to about 5% by weight of the oil-in-water emulsified spacer fluid, and
wherein the amphiphilic co-surfactant is selected from the group consisting of an alcohol; an alkyl alcohol; an aliphatic alcohol; an alicyclic alcohol; an unsaturated aliphatic alcohol; an unsaturated alicyclic alcohol; a polyhydric alcohol; an aromatic alcohol; an ethoxylated alcohol; a propoxylated alcohol; a glycol; a glycol ether; a polyglycol amine; a phenol; an ethoxylated phenol; a propoxylated phenol; and any combination thereof;

wherein the non-aqueous fluid is a paraffin and the non-aqueous fluid is present in an amount in the range of about 1% to about 10% by weight of the oil-in-water emulsified spacer fluid,
wherein the weighting agent is in the amount of about 50% by weight to about 55% by weight of the oil-in-water emulsified spacer fluid, and

introducing the oil-in-water emulsified spacer fluid into a subterranean formation comprising a residual non-aqueous fluid therein,
wherein the binary surfactant mixture in the oil-in-water emulsified spacer fluid emulsifies at least a portion of the residual non-aqueous fluid; and
wherein the combination of betaine and amphiphilic co-surfactant in a ratio of surfactant to amphiphilic co-surfactant in the range of about 1:2 to 2:1 together with paraffin in the amount of about 1% to about 10% by weight of the oil-in-water emulsified spacer fluid is able to produce an emulsion having low surfactant content which remains stable against settling for a period of time greater than about 48 hours.

2. The method of claim 1 , wherein the binary surfactant mixture increases the water wettability of the subterranean formation.

3. The method of claim 1 , wherein oil-in-water emulsified spacer fluid is a microemulsion comprising dispersed phase droplets having an average diameter in the range of from about 1 nm to about 100 nm.

4. The method of claim 1 , wherein the oil-in-water emulsified spacer fluid is a miniemulsion comprising dispersed phase droplets having an average diameter in the range of from about 50 nm to about 1 μm.

5. The method of claim 1 , wherein the oil-in-water emulsified spacer fluid is a macroemulsion comprising dispersed phase droplets having an average diameter in the range of from about 1 μm to about 100 μm.

6. The method of claim 1 , wherein the emulsified spacer fluid further comprises an additive selected from the group consisting of a salt; a weighting agent; an inert solid; a fluid loss control agent; an emulsifier; a dispersion aid; a corrosion inhibitor; an emulsion thinner; an emulsion thickener; a viscosifying agent; a gelling agent; a proppant; a lost circulation agent; a foaming agent; a gas; a pH control additive; a breaker; a biocide; a crosslinker; a stabilizer; a chelating agent; a scale inhibitor; a gas hydrate inhibitor; an oxidizer; a reducer; a friction reducer; a clay stabilizing agent; and any combination thereof.

7. The method of claim 1 further comprising:
removing the oil-in-water emulsified spacer fluid from the subterranean formation;
introducing a casing string into the subterranean formation;
introducing a cement composition into the subterranean formation so as to form a cement column in an annulus between the subterranean formation and the casing string; and
setting the cement composition forming the cement column.

8. The method of claim 7 , wherein the aqueous base fluid in the oil-in-water emulsified spacer fluid is selected from the group consisting of fresh water;
saltwater; brine; seawater; and any combination thereof.

9. The method of claim 7 , wherein the aqueous base fluid in the oil-in-water emulsified spacer fluid is present in an amount in a range of about 40% to about 70% by weight of the emulsified spacer fluid.

10. The method of claim 7 , wherein the amphiphilic co-surfactant is tertiary-butyl alcohol.

11. The method of claim 7 , wherein the emulsion is a microemulsion.

12. A method comprising:
providing an oil-in-water emulsified spacer fluid comprising a binary surfactant mixture, solvent non-aqueous base fluid, a weighting agent, and an aqueous base fluid,
wherein the binary surfactant mixture comprises a surfactant and an amphiphilic co-surfactant in a ratio of surfactant to amphiphilic co-surfactant in the range of about 1:2 to 2:1,
wherein the surfactant is a betaine present in an amount in the range of from about 0.5% to about 5% by weight of the oil-in-water emulsified spacer fluid,
wherein the amphiphilic co-surfactant is tertiary-butyl alcohol present in an amount in the range of from about 0.5% to about 5% by weight of the oil-in-water emulsified spacer fluid,

wherein the non-aqueous fluid is a paraffin and the non-aqueous fluid is present in an amount in the range of about 1% to about 10% by weight of the oil-in-water emulsified spacer fluid,
wherein the weighting agent is in the amount of about 50% by weight to about 55% by weight of the oil-in-water emulsified spacer fluid,
wherein the emulsified spacer fluid further comprises an additive selected from the group consisting of a salt; a weighting agent; an inert solid; a fluid loss control agent; an emulsifier; a dispersion aid; a corrosion inhibitor; an emulsion thinner; an emulsion thickener; a viscosifying agent; a gelling agent; a proppant; a lost circulation agent; a foaming agent; a gas; a pH control additive; a breaker; a biocide; a crosslinker; a stabilizer; a chelating agent; a scale inhibitor; a gas hydrate inhibitor; an oxidizer; a reducer; a friction reducer; a clay stabilizing agent; and any combination thereof, and

introducing the oil-in-water emulsified spacer fluid into a subterranean formation comprising a residual non-aqueous fluid therein,
wherein the binary surfactant mixture in the oil-in-water emulsified spacer fluid emulsifies at least a portion of the residual non-aqueous fluid; and
wherein the combination of betaine and tertiary butyl alcohol in a ratio of surfactant to amphiphilic co-surfactant in the range of about 1:2 to 2:1 together with paraffin in the amount of about 1% to about 10% by weight of the oil-in-water emulsified spacer fluid is able to produce an emulsion having low surfactant content which remains stable against settling for a period of time greater than about 48 hours.

Assignees

• Halliburton Energy Services Inc

Inventors

• Ravi Krishna
• Lewis Sam
• Agapiou Kyriacos

Classifications

• C09K8/26 Primary

  Oil-in-water emulsions · CPC title

• C09K8/28

  containing organic additives · CPC title

• C09K8/40 Primary

  Spacer compositions, e.g. compositions used to separate well-drilling from cementing masses · CPC title

• E21B33/14

  for cementing casings into boreholes · CPC title

• E21B21/08

  Controlling or monitoring pressure or flow of drilling fluid, e.g. automatic filling of boreholes, automatic control of bottom pressure (valve arrangements therefor E21B21/10) · CPC title