Method of increasing lubricity of brine-based drilling fluids and completion brines
View Patent ↗The lubricity of a drilling fluid or a completion fluid may be increased by incorporating into the fluid a water-soluble or water-dispersible salt of a sulfonated (sulfated) vegetable oil or a derivative thereof, such as a sulfonated (sulfated) castor oil. Suitable derivatives include the sodium, potassium, calcium, magnesium or ammonium salt. A non-ionic or anionic surfactant which is capable of enhancing the solubility of the salt may further be incorporated into the drilling fluid or completion fluid.
1. A method of increasing the lubricity or reducing the coefficient of friction of a drilling or completion fluid containing a brine by adding to the brine at least one water-soluble salt of a sulfonated (sulfated) vegetable oil or derivative thereof and an anionic or non-ionic surfactant, wherein the anionic or non-ionic surfactant solubilizes the salt of the sulfonated (sulfated) vegetable oil or derivative thereof.
2. The method of claim 1 , wherein the salt of a sulfonated (sulfated) vegetable oil is a salt of sulfonated (sulfated) castor oil.
3. The method of claim 2 , wherein the salt of the sulfonated (sulfated) vegetable oil is selected from the group consisting of sodium, potassium, calcium, magnesium and ammonium salts.
4. The method of claim 1 , wherein the surfactant is non-ionic.
5. The method of claim 4 , wherein the non-ionic surfactant is an ethoxylated alcohol.
6. The method of claim 5 , wherein the non-ionic surfactant is an ethoxylate of alkyl polyethylene glycol ether.
7. The method of claim 6 , wherein the non-ionic surfactant is a C 10 alcohol ethoxylate.
8. The method of claim 7 , wherein the C 10 alcohol ethoxylate contains eight ethylene oxide units.
9. The method of claim 1 , wherein a freezing point depressant is further added to the brine.
10. The method of claim 9 , wherein the freezing point depressant is a C 1 -C 8 alcohol, glycol, polyglycol or glycol ether.
11. The method of claim 10 , wherein the freezing point depressant is a glycol ether.
12. The method of claim 1 , wherein the surfactant is an anionic surfactant.
13. A method of increasing the lubricity or reducing the coefficient of friction of a completion fluid containing a brine by adding to the completion fluid at least one water-soluble salt of a sulfonated (sulfated) vegetable oil or derivative thereof and a surfactant, wherein the surfactant solubilizes the salt of the sulfonated (sulfated) vegetable oil or derivative thereof.
14. The method of claim 13 , wherein the salt of a sulfonated (sulfated) vegetable oil is a salt of sulfonated (sulfated) castor oil.
15. The method of claim 14 , wherein the salt of the sulfonated (sulfated) vegetable oil is selected from the group consisting of sodium, potassium, calcium, magnesium and ammonium salts.
16. The method of claim 13 , wherein the surfactant is non-ionic.
17. The method of claim 16 , wherein the non-ionic surfactant is an ethoxylated alcohol.
18. The method of claim 17 , wherein the non-ionic surfactant is an ethoxylate of alkyl polyethylene glycol ether.
19. The method of claim 18 , wherein the non-ionic surfactant is a C 10 alcohol ethoxylate.
20. The method of claim 19 , wherein the C 10 alcohol ethoxylate contains eight ethylene oxide units.
21. A method of increasing the lubricity or reducing the coefficient of friction of a drilling or completion fluid containing a brine by adding to the drilling or completion fluid at least one water-soluble salt of a sulfonated (sulfated) vegetable oil or derivative thereof and an anionic or non-ionic surfactant, wherein the anionic or non-ionic surfactant solubilizes the salt of said sulfonated (sulfated) vegetable oil or derivative thereof.
22. The method of claim 21 , wherein the salt of a sulfonated (sulfated) vegetable oil is a salt of a sulfonated (sulfated) vegetable oil.
23. The method of claim 22 , wherein the salt of a sulfonated (sulfated) vegetable oil is a salt of sulfonated (sulfated) castor oil.
24. The method of claim 23 , wherein the salt of sulfonated (sulfated) vegetable oil is selected from the group consisting of sodium, potassium, calcium, magnesium and ammonium salts.
25. The method of claim 21 , wherein the surfactant is non-ionic.
26. The method of claim 25 , wherein the non-ionic surfactant is an ethoxylated alcohol.
27. The method of claim 26 , wherein the non-ionic surfactant is an ethoxylate of alkyl polyethylene glycol ether.
28. The method of claim 27 , wherein the non-ionic surfactant is a C 10 alcohol ethoxylate.
29. The method of claim 28 , wherein the C 10 alcohol ethoxylate contains eight ethylene oxide units.
30. The method of claim 21 , wherein a freezing point depressant is further added to the brine.
31. The method of claim 21 , wherein the fluid is a completion fluid.