Method of extracting and reutilizing surfactants from emulsions using sulfonated alkyl benzenes and ethoxylated phenols

Claim 1

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume surfactant-rich middle phase from produced emulsions comprising oil, water and surfactant, which comprises: mixing a produced emulsion with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of produced emulsion and first extracting compound solution to separate into at least three phases, including a substantially surfactant-free and water-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and water, and an oil-free aqueous phase; mixing about a 0.1% to about 3.0% volume of a second extracting compound per volume of first middle phase with said first middle phase, said second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing 0 to about 12 carbon atoms; and allowing the mixture of first low volume middle phase and ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively small volume surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase.

Claim 2

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume surfactant-rich middle phase from produced emulsions comprising oil, water and surfactant, which comprises: mixing a produced emulsion with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of produced emulsion and first extracting compound solution to separate into at least three phases, including a substantially surfactant-free and water-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and water, and an oil-free aqueous phase; mixing about a 0.1% to about 3.0% volume of a second extracting compound per volume of first middle phase with said first middle phase, said second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing 0 to about 12 carbon atoms; and allowing the mixture of first low volume middle phase and ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively small volume surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase.

Claim 13

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume, surfactant-rich middle phase from produced emulsions comprising oil, brine and surfactant, which comprises: allowing the produced emulsion to settle into two phases, an emulsion phase and an aqueous phase; mixing the emulsion phase with a solution containing about 0.1% to about 3.0% of a water soluble sulfonate surfactant having an equivalent weight of about 250 to about 450 and about 0.3% to about 6% of a first extracting compound selected from the group consisting of the sodium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate at a temperature of about 25° C. to about 70° C.; allowing the mixture of emulsion, and first extracting compound and water soluble sulfonate solution to separate at a temperature of about 25° C. to about 70° C. into at least three phases, including a substantially surfactant-free and brine-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and brine and an oil-free aqueous phase; mixing about a 0.3% to about 1.5% volume of ethoxylated phenol having about two to about eight ethylene oxide groups per volume of first middle phase with said first middle phase at a temperature of about 30° C. to about 50° C.; and allowing the mixture of first middle phase and ethoxylated phenol to separate at a temperature of about 30° C. to about 50° C. into at least two phases, including a substantially surfactant-free and brine-free crude oil phase, a second relatively small volume, surfactant-rich middle phase containing surfactant, oil and brine, and usually, a third oil-free aqueous phase.

Claim 14

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume, surfactant-rich middle phase from produced emulsions comprising oil, brine and surfactant, which comprises: allowing the produced emulsion to settle into two phases, an emulsion phase and an aqueous phase; mixing the emulsion phase with a solution containing about 0.1% to about 3.0% of a water soluble sulfonate surfactant having an equivalent weight of about 250 to about 450 and about 0.3% to about 6% of a first extracting compound selected from the group consisting of the sodium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate at a temperature of about 25° C. to about 70° C.; allowing the mixture of emulsion, and first extracting compound and water soluble sulfonate solution to separate at a temperature of about 25° C. to about 70° C. into at least three phases, including a substantially surfactant-free and brine-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and brine and an oil-free aqueous phase; mixing about a 0.3% to about 1.5% volume of ethoxylated phenol having about two to about eight ethylene oxide groups per volume of first middle phase with said first middle phase at a temperature of about 30° C. to about 50° C.; and allowing the mixture of first middle phase and ethoxylated phenol to separate at a temperature of about 30° C. to about 50° C. into at least two phases, including a substantially surfactant-free and brine-free crude oil phase, a second relatively small volume, surfactant-rich middle phase containing surfactant, oil and brine, and usually, a third oil-free aqueous phase.

Claim 15

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume surfactant-rich middle phase from produced emulsions comprising oil, water and surfactant, which comprises: mixing a produced emulsion with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of produced emulsion and first extracting compound solution to separate into at least three phases, including a substantially surfactant-free and water-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and water, and an oil-free aqueous phase; mixing the first middle phase and aqueous phase together and allowing them to separate into upper and lower phases; mixing about 0.1% to about 3.0% volume of a second extracting compound per volume of upper phase with said upper phase, said second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing 0 to about 12 carbon atoms; and allowing the mixture of said upper phase and ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively small volume, surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase.

Claim 16

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume surfactant-rich middle phase from produced emulsions comprising oil, water and surfactant, which comprises: mixing a produced emulsion with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of produced emulsion and first extracting compound solution to separate into at least three phases, including a substantially surfactant-free and water-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and water, and an oil-free aqueous phase; mixing the first middle phase and aqueous phase together and allowing them to separate into upper and lower phases; mixing about 0.1% to about 3.0% volume of a second extracting compound per volume of upper phase with said upper phase, said second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing 0 to about 12 carbon atoms; and allowing the mixture of said upper phase and ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively small volume, surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase.

Claim 17

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume surfactant-rich middle phase from produced emulsions comprising oil, water and surfactant, which comprises: mixing a produced emulsion with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of produced emulsion and first extracting compound solution to separate into at least three phases, including a substantially surfactant-free and water-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and water, and an oil-free aqueous phase; mixing together the first middle phase, aqueous phase and about a 0.1% to about 3% by volume of a second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing about 0 to about 12 carbon atoms; and allowing the mixture of the first middle phase, the aqueous phase and the ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively small volume, surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase.

Claim 18

A method for extracting and concentrating enhanced oil recovery surfactants into a relatively small volume surfactant-rich middle phase from produced emulsions comprising oil, water and surfactant, which comprises: mixing a produced emulsion with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of produced emulsion and first extracting compound solution to separate into at least three phases, including a substantially surfactant-free and water-free crude oil phase, a first relatively low volume middle phase containing surfactant, oil and water, and an oil-free aqueous phase; mixing together the first middle phase, aqueous phase and about a 0.1% to about 3% by volume of a second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing about 0 to about 12 carbon atoms; and allowing the mixture of the first middle phase, the aqueous phase and the ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively small volume, surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase.

Claim 19

A method for reutilizing surfactants in a surfactant flood that are entrained within a produced emulsion comprising oil, water and surfactant, which comprises: allowing the produced emulsion to settle into two phases, an emulsion phase and an aqueous phase; mixing the emulsion phase with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of emulsion and first extracting compound solution to separate into at least three phases, mixing about a 0.1% to about 3% volume of a second extracting compound per volume of first middle phase with said first middle phase, said second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing 0 to about 12 carbon atoms; allowing the mixture of first middle phase and ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively lower volume, surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase; and injecting the second middle phase as a surfactant slug in a surfactant flood.

Claim 20

A method for reutilizing surfactants in a surfactant flood that are entrained within a produced emulsion comprising oil, water and surfactant, which comprises: allowing the produced emulsion to settle into two phases, an emulsion phase and an aqueous phase; mixing the emulsion phase with an extracting compound solution of water containing about 0.3% to about 6.0% of a first extracting compound selected from the group consisting of the alkali metal salts and ammonium salts of propyl benzene sulfonate, cumene sulfonate, ethyl benzene sulfonate, methyl ethyl benzene sulfonate, diethyl benzene sulfonate, methyl propyl benzene sulfonate, xylene sulfonate and dicyclopentadiene sulfonate; allowing the mixture of emulsion and first extracting compound solution to separate into at least three phases, mixing about a 0.1% to about 3% volume of a second extracting compound per volume of first middle phase with said first middle phase, said second extracting compound consisting of an ethoxylated phenol with an average of about one to about fifteen ethylene oxide groups and having an alkyl side chain containing 0 to about 12 carbon atoms; allowing the mixture of first middle phase and ethoxylated phenol to separate into at least two phases, including a substantially surfactant-free and water-free crude oil phase, a second relatively lower volume, surfactant-rich middle phase containing surfactant, oil and water, and usually, a third oil-free aqueous phase; and injecting the second middle phase as a surfactant slug in a surfactant flood.