Completion fluid for injection into wellbore
A method of completing a wellbore in a hydrocarbon-containing subterranean formation includes injecting a completion fluid into the wellbore to form a hydrostatic gradient at a hydrocarbon-producing depth in the wellbore. The completion fluid is an aqueous solution including 10 to 20 w/v % of a dicationic surfactant of Formula (I) having an alkyl linker and a lipophilic tail. The completion fluid reduces a torque of the wellbore by at least 25% at a temperature of at least 150° F.
1 . A method of completing a wellbore in a hydrocarbon-containing subterranean formation, comprising:
injecting a completion fluid into the wellbore to form a hydrostatic gradient at a hydrocarbon-producing depth in the wellbore,
wherein the completion fluid is an aqueous solution comprising 10 to 20 w/v % of a dicationic surfactant of Formula (I) having an alkyl linker and a lipophilic tail
where:
c is from 1 to 20 and represents the alkyl linker,
X represents an anionic counterion,
a is from 1 to 20 and represents the lipophilic tail, and
b is from 1 to 20, and
wherein the completion fluid reduces a torque of the wellbore by at least 25% at a temperature of 150 to 300° F. at a surfactant loading of 10 wt./vol. % based on the total volume of the completion fluid.
2 . The method of claim 1 , wherein the completion fluid is an aqueous solution comprising a brine comprising at least one selected from the group consisting of an alkali metal salt and an alkaline earth metal salt, and
wherein a is from 10 to 20, b is from 10 to 16, and c is from 6 to 8.
3 . The method of claim 1 , wherein the completion fluid has a density of 1 to 3 g/cm 3 .
4 . The method of claim 1 , wherein the completion fluid has a viscosity of 1 to 20 cP.
5 . The method of claim 1 , further comprises, before the injecting:
inserting a steel casing string into the wellbore, then sealing a perimeter of the wellbore formed by the casing string by pumping a cement slurry into an annulus between the wellbore wall and the steel casing string;
curing the cement slurry to encase the perimeter of the wellbore in a cement coating; and
inserting a perforating gun into the wellbore and shooting the perforating gun to create a plurality of openings in the perimeter of the wellbore and the cement coating.
6 . The method of claim 1 , wherein the anionic counterion is at least one selected from the group consisting of chlorine and bromine.
7 . The method of claim 1 , wherein the completion fluid is an aqueous solution comprising a brine comprising at least one selected from the group consisting of NaCl, KCl, NaHCO 3 , NaOH, CaCl 2 , CaCO 3 , MgSO 4 , BaSO 4 , SrCl 2 , KOH, LiHCO 3 , Na 2 CO 3 , and KNO 3 .
8 . The method of claim 1 , wherein the completion fluid has a density of 1.2 to 2 g/cm 3 .
9 . The method of claim 1 , wherein the anionic counterion is bromine.
10 . The method of claim 1 , wherein the completion fluid has a lubricity coefficient of 0.05 to 0.3 at a temperature of 150 to 300° F.
11 . The method of claim 1 , wherein the completion fluid further comprises at least one additive selected from the group consisting of emulsifiers, viscosifiers, fluid-loss control agents, corrosion inhibitors, defoamers, anti-scalants, deflocculants, lubricants, wellbore strengthening materials, high temperature/high pressure control additives, and coating enhancement agents.
12 . The method of claim 1 , wherein the completion fluid is an aqueous solution comprising a brine comprising at least one selected from the group consisting of NaCl and CaCl 2 .
13 . The method of claim 1 , wherein the completion fluid is an aqueous solution comprising a brine comprising NaCl.
14 . The method of claim 1 , wherein the completion fluid has a lubricity coefficient of 0.06 to 0.13 at a temperature of 150 to 300° F.
15 . The method of claim 1 , wherein the completion fluid reduces a torque of the wellbore by at least 50% at a temperature of 150 to 300° F.
16 . The method of claim 1 , wherein the completion fluid is an aqueous solution comprising a brine comprising CaCl 2 .
17 . The method of claim 1 , wherein the completion fluid has a density of 1.2 to 1.6 g/cm 3 .
18 . The method of claim 1 , wherein the completion fluid has a viscosity of 1 to 6 cP.
19 . The method of claim 1 , wherein the completion fluid has a density of 50 to 75.
20 . The method of claim 1 , wherein the completion fluid has a lubricity coefficient of 0.07 to 0.19 at a temperature of 150 to 300° F.