Modified acid compositions as alternatives to conventional acids in the oil and gas industry

Patent metadata

Field	Value
Publication number	US-11898097-B2
Application number	US-202117195084-A
Country	US
Kind code	B2
Filing date	Mar 8, 2021
Priority date	Dec 22, 2017
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

An aqueous modified acid composition for use in oil industry activities, said composition comprising: an amino acid, an alkanolamine and strong acid wherein the mineral acid: alkanolamine/amino acid are present in a molar ratio of not more than 15:1, preferably not more than 10:1; it can also further comprise a metal iodide or iodate. Said composition demonstrates advantages over known conventional acids and modified acids.

First claim

What is claimed is:

1. An aqueous modified acid composition comprising:
HCl;
an amino acid; and
an alkanolamine;
wherein the mineral acid: alkanolamine/amino acid are present in a molar ratio of not more than 15:1;
wherein the amino acid is selected from the group consisting of: lysine, glycine, valine, arginine, histidine, methionine and combinations thereof; and
wherein the aqueous modified acid composition has a pH of less than 1.

2. An aqueous modified acid composition according to claim 1 , wherein the amino acid: alkanolamine proportion ranges from 1%: 99% to 99%: 1%.

3. An aqueous modified acid composition according to claim 1 , wherein the amino acid: alkanolamine proportion ranges from 20%: 80% to 80%: 20%.

4. An aqueous modified acid composition according to claim 1 , wherein the amino acid: alkanolamine proportion ranges from 30%: 70% to 70%: 30%.

5. An aqueous modified acid composition according to claim 1 , wherein the amino acid: alkanolamine proportion is 50%: 50%.

6. The aqueous modified acid composition according to claim 1 , wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 10:1.

7. The aqueous modified acid composition according to claim 1 , wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 7.0:1.

8. The aqueous modified acid composition according to claim 1 , wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 4:1.

9. The aqueous modified acid composition according to claim 1 , wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 3:1.

10. The aqueous modified acid composition according to claim 1 , wherein the HCl: alkanolamine/amino acid are present in a molar ratio ranging from 3:1 to 12:1.

11. The aqueous modified acid composition according to claim 1 , wherein the HCl: alkanolamine/amino acid are present in a molar ratio ranging from 5:1 to 10:1.

12. The aqueous modified acid composition according to claim 1 , wherein the alkanolamine is selected from the group consisting of: monoethanolamine; diethanolamine; triethanolamine and combinations thereof.

13. The aqueous modified acid composition according to claim 1 , wherein the alkanolamine is monoethanolamine.

14. The aqueous modified acid composition according to claim 1 , wherein the alkanolamine is diethanolamine.

15. The aqueous modified acid composition according to claim 1 , further comprising a metal iodide or iodate selected from the group consisting of: cuprous iodide; potassium iodide; sodium iodide; lithium iodide and combinations thereof.

16. The aqueous modified acid composition according to claim 1 , further comprising an alkynyl alcohol or derivative thereof present in a concentration ranging from 0.01 to 5% w/w.

17. The aqueous modified acid composition according to claim 16 , wherein the alkynyl alcohol or derivative thereof is propargyl alcohol or a derivative thereof.

18. The aqueous modified acid composition according to claim 15 , wherein the metal iodide is present in a concentration ranging from 0.1 to 2% by weight of the total weight of the composition.

19. The use of an aqueous modified acid composition in an oil industry activity, said composition comprising:
HCl;
an amino acid; and
an alkanolamine;
wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 15:1,
wherein the amino acid is selected from the group consisting of: lysine, glycine, valine, arginine, histidine, methionine and combinations thereof;
wherein the aqueous modified acid composition has a pH of less than 1; and
wherein the use comprises an activity selected from the group consisting of: stimulate formations; assist in reducing breakdown pressures during downhole pumping operations; treat wellbore filter cake post drilling operations; assist in freeing stuck pipe; descale pipelines and/or production wells; increase injectivity of injection wells; lower the pH of a fluid; remove undesirable scale on a surface selected from the group consisting of: equipment, wells and related equipment and facilities; fracture wells; complete matrix stimulations; conduct annular and bullhead squeezes & soaks; pickle tubing, pipe and/or coiled tubing; increase effective permeability of formations; reduce or remove wellbore damage; clean perforations; and solubilize limestone, dolomite, calcite and combinations thereof.

20. A method of treating a metal surface with a composition comprising:
HCl;
an amino acid; and
an alkanolamine;
wherein the HCl: alkanolamine/amino acid are present in a molar ratio of not more than 15:1,
wherein the amino acid is selected from the group consisting of: lysine, glycine, valine, arginine, histidine, methionine and combinations thereof;
wherein the composition has a pH of less than 1;
said method comprising the steps of:
providing said composition;
exposing said metal surface to said composition;
allowing said composition a sufficient period of time to act upon said surface; and
optionally, removing the acid composition when the exposure time has been determined to be sufficient for the operation to be complete or sufficiently complete.

Assignees

• Fluid Energy Group Ltd
• Dorf Ketal Chemicals Fze

Inventors

• Purdy Clay
• Weissenberger Markus

Classifications

• C09K8/74 Primary

  combined with additives added for specific purposes · CPC title

• C09K8/528

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

• C23F11/04

  in markedly acid liquids · CPC title

• C09K2208/32

  Anticorrosion additives · CPC title

• E21B37/06

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