Topical defoamer and demulsifier
View Patent ↗Compounds of the formula H(CH 2 ) z COO—[C 2 H 4 O] x C y H 2y+1 where z is 0-2, x is an integer from 1 to 5 and y is an integer from 4-9 are used as emulsion breakers and defoamers in formation treatment fluids in the recovery of hydrocarbons from subterranean formations. A preferred material has the formula HCOO—[C 2 H 4 0] 3 C 6 H 7 .
1. Method of controlling foaming or emulsifying in a subterranean formation treatment fluid in a subterranean hydrocarbon-producing formation comprising including in said formation treatment fluid at least 1% by weight of the foaming or emulsifying constituent therein of a compound of the formula H(CH 2 ) z COO—[C 2 H 4 O] x C y H 2y+1 , or of the formula H(CH 2 ) z COO—[C 2 H 4 O] x C 6 H 5 , where z is 0-2, x is an integer from 1 to 5 and y is an integer from 4-9, wherein the foaming or emulsifying constituent comprises an amine oxide.
2. Method of claim 1 wherein said subterranean hydrocarbon producing formation contains more than about 0.01% by weight, based on the hydrocarbons to be removed, paraffins or waxes having more than 19 carbon atoms.
3. Method of claim 2 wherein the subterranean formation is at a temperature of at least 100 degrees Fahrenheit.
4. Method of claim 1 wherein z is 0-1, x is 2-4, and y is 5-7.
5. Method of claim 1 wherein z is 0, x is 3, and y is 6.
6. Method of claim 1 wherein said compound of the formula H(CH 2 ) z COO—[C 2 H 4 O] x C y H 2y+1 is present in a molar ratio 2:1 to 1:2 to said foaming or emulsifying constituent.
7. Method of claim 1 wherein said foaming or emulsifying constituent comprises an anionic surfactant.
8. A method of controlling foaming or emulsifying in a subterranean formation treatment fluid having a surfactant in a subterranean hydrocarbon-producing formation, comprising:
adding a defoaming or demulsifying compound of the formula H(CH 2 ) z COO—[C 2 H 4 0] x C y H 2y+1 or of the formula H(CH 2 ) z COO—[C 2 H 4 0 ] x C 6 H 5 , where z is an integer from 0 to 2, x is an integer from 1 to 5, and y is an integer from 4 from 9, wherein the defoaming or demulsifying compound is present in a molar ratio 2:1 to 1:2 to the surfactant.
9. The method of claim 8 , wherein the subterranean hydrocarbon producing formation contains more than about 0.01% by weight, based on the hydrocarbons to be removed, paraffins or waxes having more than 19 carbon atoms.
10. The method of claim 9 , wherein the subterranean formation is at a temperature of at least 100 degrees Fahrenheit.
11. The method of claim 8 , wherein z is 0-1, x is 2-4, and y is 5-7.
12. The method of claim 8 , wherein z is 0, x is 3, and y is 6.
13. The method of claim 8 , wherein the surfactant comprises an amine oxide.
14. The method of claim 8 , wherein the surfactant comprises an anionic surfactant.
15. The method of claim 8 , wherein the defoaming or demulsifying compound is added after the formation fracturing fluid is supplied into the formation.
16. The method of claim 8 , wherein the formation treatment fluid comprises fracturing fluid.
17. The method of claim 8 , wherein a pH of the formation treatment fluid is reduced after the defoaming or demulsifying compound is added.
18. The method of claim 1 , wherein the compound is effective to break a foam or emulsion made by the amine oxide.
19. The method of claim 1 , wherein the compound reduces a foam made by the amine oxide by reducing the pH.
20. The method of claim 8 , wherein the compound is effective to break a foam or emulsion made by the surfactant.