Abstract: A method of producing fluid from a formation containing hydrocarbons in which an aqueous polymer preflush fluid is injected into the formation followed by injection of an aqueous polymer displacement fluid, where the aqueous polymer preflush fluid has a total dissolved solids content that is greater than the total dissolved solids content of the aqueous polymer displacement fluid.

Abstract: Recovering oil from a subterranean formation is disclosed, comprising processing a source water to produce a processed water stream and a reject water stream; injecting a first fluid into an injection well toward a first downhole exhaust, wherein the first fluid comprises the processed water stream; and injecting a second fluid into the injection well toward a second downhole exhaust, wherein the second fluid comprises the reject water stream or a produced water stream, wherein the first fluid is separated from the second fluid within the injection well; and producing oil via a production well.

Abstract: A process for producing a fluid containing oil and water from an oil-bearing formation and separating an oil phase and an aqueous phase from the produced fluid. An aqueous polymer mixture is formed by mixing polymer in water having a total dissolved solids content of from 200 ppm to 15,000 ppm. The aqueous polymer mixture is injected into an oil-bearing formation, and, after injecting the aqueous polymer mixture into the formation, a fluid is produced from the oil-bearing formation containing an oil phase and an aqueous polymer-containing phase. Brine is mixed with the produced fluid to enhance separation of the oil phase from the aqueous polymer phase.

Abstract: The present invention is directed to a process for producing and separating oil. An aqueous fluid having an ionic content of at most 0.15 M and a total dissolved solids content of from 200 ppm to 10,000 ppm is introduced into an oil-bearing formation. Oil and water are produced from the formation subsequent to the introduction of the aqueous fluid into the formation. A demulsifier and a brine solution having a total dissolved solids content of greater than 10,000 ppm are mixed with the oil and water produced from the formation. Oil is then separated from the mixture of oil, water, demulsifier, and brine solution.

Abstract: Recovering oil from a subterranean formation is disclosed, comprising processing a source water to produce a processed water stream and a reject water stream; injecting a first fluid into an injection well toward a first downhole exhaust, wherein the first fluid comprises the processed water stream; and injecting a second fluid into the injection well toward a second downhole exhaust, wherein the second fluid comprises the reject water stream or a produced water stream, wherein the first fluid is separated from the second fluid within the injection well; and producing oil via a production well.

Abstract: A method of producing fluid from a formation containing hydrocarbons in which an aqueous polymer preflush fluid is injected into the formation followed by injection of an aqueous polymer displacement fluid, where the aqueous polymer preflush fluid has a total dissolved solids content that is greater than the total dissolved solids content of the aqueous polymer displacement fluid.

Abstract: The present invention is directed to a process for producing a fluid containing oil and water from an oil-bearing formation and separating an oil phase and an aqueous phase from the produced fluid. An aqueous polymer mixture is formed by mixing polymer in water having a total dissolved solids content of from 200 ppm to 15,000 ppm. The aqueous polymer mixture is injected into an oil-bearing formation, and, after injecting the aqueous polymer mixture into the formation, a fluid is produced from the oil-bearing formation containing an oil phase and an aqueous polymer-containing phase. Brine is mixed with the produced fluid to enhance separation of the oil phase from the aqueous polymer phase.

Abstract: The present invention is directed to a process for producing and separating oil. An aqueous fluid having an ionic content of at most 0.15 M and a total dissolved solids content of from 200 ppm to 10,000 ppm is introduced into an oil-bearing formation. Oil and water are produced from the formation subsequent to the introduction of the aqueous fluid into the formation. A demulsifier and a brine solution having a total dissolved solids content of greater than 10,000 ppm are mixed with the oil and water produced from the formation. Oil is then separated from the mixture of oil, water, demulsifier, and brine solution.

Abstract: The present invention is directed to a system for producing and separating oil. The system comprises an oil-bearing formation, a low salinity aqueous fluid having an ionic strength of less than 0.15M and having a total dissolved solids content of from 200 ppm to 10000 ppm, a brine solution having a total dissolved solids content of greater than 10000 ppm, and a demulsifier. The system further comprises a mechanism for introducing the low salinity aqueous fluid into and oil-bearing formation, a mechanism for producing oil and water from the formation subsequent to introducing the low salinity aqueous fluid into the formation, and a mechanism for contacting the brine solution and the demulsifier with the oil and water produced from the formation and for separating the produced oil from the produced water.

Abstract: There is disclosed a method for enhancing recovery of crude oil from a porous subterranean carbonate formation of which the pore spaces contain crude oil and connate water, the method comprising determining an ionic strength of the connate water; and injecting an aqueous displacement fluid having a lower ionic strength than the connate water into the formation.