Granted Patent B1

US 12,515,973 · App. 18/913,243 · Granted Jan 6, 2026

Inventors: Kristina Henkel Holan (Houston, TX); Enrique Antonio Reyes (Houston, TX)

Assignee: Halliburton Energy Services, Inc.

C02F5/105E21B37/06E21B43/28

Abstract

Claims (31)

1 . A method for treating geothermal wells comprising:

introducing a treatment fluid into a wellbore of a geothermal well having geothermal scale,

wherein the treatment fluid comprises an ester, a fluoride-containing source, and a base fluid, wherein a molar ratio of fluoride-containing source to ester is about 1:1 to about 5:1, wherein the ester comprises methyl lactate, and wherein the fluoride-containing source comprises hydrofluoric acid;

contacting the geothermal scale with the treatment fluid; and

removing at least a portion of the geothermal scale from the geothermal well using the treatment fluid.

2 . The method of claim 1 , wherein the ester has a concentration from 1 mol/L to about 5 mol/L.

3 . The method of claim 1 , wherein the ester has a concentration from 1 mol/L to about 3.5 mol/L.

4 . The method of claim 1 , wherein the fluoride containing source has a concentration from 1 mol/L to about 5 mol/L.

5 . The method of claim 1 , wherein the fluoride containing source has a concentration from 3 mol/L to about 5 mol/L.

6 . The method of claim 1 , wherein the molar ratio of fluoride-containing source to ester is about 1:1 to about 3.125:1.

7 . The method of claim 1 , wherein the treatment fluid further comprises a corrosion inhibitor.

8 . The method of claim 1 , wherein the treatment fluid further comprises at least one corrosion inhibitor comprising crotonaldehyde and its Mannich bases.

9 . The method of claim 1 , wherein the treatment fluid further comprises at least one corrosion inhibitor intensifier comprising phosphorous salts.

10 . The method of claim 1 , wherein the base fluid comprises ammonium chloride.

11 . The method of claim 1 , wherein the treatment fluid has a pH from about 6 to about 8.

12 . A method for treating geothermal wells comprising:

introducing a treatment fluid into a wellbore of a geothermal well,

wherein the treatment fluid comprises an ester, wherein the ester comprises methyl lactate a fluoride-containing source, wherein the fluoride-containing source comprises hydrofluoric acid, and a base fluid, wherein a molar ratio of fluoride-containing source to ester is about 1:1 to about 5:1, and

wherein the geothermal well has geothermal scale and a bottomhole temperature from about 350° F. to about 600° F.;

contacting the geothermal scale with the treatment fluid;

removing at least a portion of the geothermal scale from the geothermal well using the treatment fluid;

mixing a corrosion inhibitor to the treatment fluid at surface; and

pumping the treatment fluid comprising a corrosion inhibitor downhole.

13 . The method of claim 12 , wherein introducing the treatment fluid into the wellbore of the geothermal well comprises pumping a quarter of a volume of the wellbore of the geothermal well.

14 . The method of claim 12 , wherein the molar ratio of fluoride-containing source to ester is about 1:1 to about 3.125:1.

15 . The method of claim 12 , wherein the ester has a concentration from 1 mol/L to about 3.5 mol/L.

16 . A method of matrix acidizing comprising:

introducing a treatment fluid into a wellbore of a formation,

wherein the treatment fluid comprises an ester, a fluoride-containing source, at least one corrosion inhibitor comprising crotonaldehyde and its Mannich bases, and a base fluid, wherein a molar ratio of fluoride-containing source to ester is about 1:1 to about 5:1;

contacting the formation with the treatment fluid; and

improving a permeability of the formation using the treatment fluid.

Assignments (1)

References Cited (17)