Use of taurine additives in enhanced oil recovery with anionic surfactants

Claim 1

In a method for recovering petroleum from a subterranean, petroleum-bearing formation penetrated by at least one injection well and at least one production well, said recovery method being of the type wherein an aqueous fluid comprising anionic surfactant is injected into the formation via the injection well, and oil displaced by the injected fluid is recovered from the formation via the production well, wherein the improvement comprises adding a taurine to said aqueous fluid comprising an anionic surfactant, said taurine having the following formula: ##STR4## wherein R 1 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, R 2 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, and X is selected from the group comprising NH 2 and NH 3 + .

Claim 5

A method for increasing the salt tolerance of an anionic surfactant for use in enhanced oil recovery operations, said method comprising blending an effective amount of a taurine with said anionic surfactant prior to said use, said taurine having the formula ##STR5## wherein R 1 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, R 2 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, and X is selected from the group comprising NH 2 and NH 3 + .

Claim 6

A method for increasing the salt tolerance of an anionic surfactant for use in enhanced oil recovery operations, said method comprising blending an effective amount of a taurine with said anionic surfactant prior to said use, said taurine having the formula ##STR5## wherein R 1 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, R 2 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, and X is selected from the group comprising NH 2 and NH 3 + .

Claim 7

A method for increasing the divalent ion tolerance of an anionic surfactant for use in enhanced oil recovery operations, said method comprising blending an effective amount of a taurine with said anionic surfactant prior to said use, said taurine having the formula ##STR6## wherein R 1 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, R 2 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, and X is selected from the group comprising NH 2 and NH 3 + .

Claim 8

A method for increasing the divalent ion tolerance of an anionic surfactant for use in enhanced oil recovery operations, said method comprising blending an effective amount of a taurine with said anionic surfactant prior to said use, said taurine having the formula ##STR6## wherein R 1 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, R 2 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, and X is selected from the group comprising NH 2 and NH 3 + .

Claim 10

A method for recovering petroleum from a subterranean petroleum-bearing formation, penetrated by at least one injection well and at least one production well, said method comprising: injecting into said formation via said injection well an aqueous fluid comprising an effective amount of a taurine blended with an amount of an anionic surfactant system greater than the amount of taurine; said taurine having the formula ##STR7## wherein R 1 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, R 2 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, and X is selected from the group comprising NH 2 and NH 3 + , driving said aqueous fluid through said formation toward said production well; and recovering displaced oil from said formation via said production well.

Claim 11

A method for recovering petroleum from a subterranean petroleum-bearing formation, penetrated by at least one injection well and at least one production well, said method comprising: injecting into said formation via said injection well an aqueous fluid comprising an effective amount of a taurine blended with an amount of an anionic surfactant system greater than the amount of taurine; said taurine having the formula ##STR7## wherein R 1 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, R 2 is selected from the group comprising hydrogen, a phenyl group, and alkyl groups having from about 1-4 carbon atoms, and X is selected from the group comprising NH 2 and NH 3 + , driving said aqueous fluid through said formation toward said production well; and recovering displaced oil from said formation via said production well.