Methods for the inhibition of salt blockages in oil and gas wells

• US 7,028,776 B2
• Filed: 03/13/2003
• Issued: 04/18/2006
• Est. Priority Date: 03/13/2002
• Status: Expired due to Fees

• Current Assignee: BJ Services Company
• Original Assignee: BJ Services Company
• Inventors: Kirk, Joseph W.
• Primary Examiner(s): SUCHFIELD, GEORGE A
• Application Number:
  US10/249,069
• Publication Number:
  US 20030173087A1
• Time in Patent Office: 1,132 Days
• Field of Search: 166/308.6, 166/309, 166/310, 166/371, 166/250.01, 166/311, 166/312, 507/241, 507/259, 507/266, 507/202, 507/244, 507/927, 507/928
• US Class Current: 166/309
• CPC Class Codes: C09K 8/528 inorganic depositions, e.g. sulfates or carbonates
• CPC Class Codes: C09K 8/62 Compositions for forming crevices or fractures
• CPC Class Codes: C09K 8/703 Foams
• CPC Class Codes: Y10S 507/927 Well cleaning fluid

Abstract

Compositions and methods for the inhibition of salt formation in oil and gas wells are disclosed. In particular, nitrilotriacetamide and its salts are effective at treating existing salt formations, and in inhibiting formation of new deposits.

Claims

1. A method of reducing the amount of crystallized salt in an oil and/or gas well, the method comprising:

selecting an oil and/or gas well containing crystallized salt;

providing a fluid comprising water and a salt inhibitor selected from the group consisting of nitrilotriacetamide and a nitrilotriacetamide salt; and

pumping the fluid into the well;

wherein the amount of crystallized salt is reduced.

2. The method of claim 1, wherein the nitrilotriacetamide salt is a hydrochloric acid salt or a sulfuric acid salt.

3. The method of claim 1, wherein the concentration of the inhibitor is about 40 ppm to about 400 ppm.

4. The method of claim 1, wherein the fluid further comprises a surfactant.

5. The method of claim 1, wherein the fluid further comprises a foaming agent.

6. The method of claim 5, wherein the foaming agent is nonyl phenol ethoxylates, sulfamic acid derivatives of ethoxylated alcohols, ammonium dodecylbenzenesulfonate, or potassium dodecylbenzenesulfonate.

7. The method of claim 1, wherein the pumping step comprises continuous addition of fluid into the wellbore.

8. The method of claim 1, further comprising a step of pumping water into the well prior to pumping the fluid into the well.

9. A method of reducing the amount of crystallized salt in an oil and/or gas well, the method comprising:

selecting an oil and/or gas well containing crystallized salt;

providing a fluid comprising water, a salt inhibitor selected from the group consisting of nitrilotriacetamide and a nitrilotriacetamide salt, and a foaming agent selected from the group consisting of nonyl phenol ethoxylates, sulfamic acid derivatives of ethoxylated alcohols, ammonium dodecylbenzenesulfonate, and potassium dodecylbenzenesulfonate; and

pumping the fluid into the well;

wherein the amount of crystallized salt is reduced.

10. The method of claim 9, wherein the nitrilotriacetamide salt is a hydrochloric acid salt or a sulfuric acid salt.

11. The method of claim 9, wherein the concentration of the inhibitor is about 40 ppm to about 400 ppm.

12. The method of claim 9, wherein the fluid further comprises a surfactant.

13. The method of claim 9, wherein the pumping step comprises continuous addition of fluid into the wellbore.

14. The method of claim 9, further comprising a step of pumping water into the well prior to pumping the fluid into the well.