Abstract: A process for mineral oil production, in which an aqueous formulation comprising at least one water-soluble, hydrophobically associating copolymer (A) and at least one nonionic and/or anionic surfactant (B) is injected through at least one injection borehole into a mineral oil deposit, and crude oil is withdrawn from the deposit through at least one production borehole, wherein the water-soluble, hydrophobically associating copolymer comprises at least acrylamide or derivatives thereof, a monomer having anionic groups and a monomer which can bring about the association of the copolymer, and aqueous formulation, which is suitable for execution of the process.

Abstract: Methods for enhanced oil recovery from a subterranean formation including adding a first salt to a first aqueous stream to form a first injection stream with an increased concentration of a first ion. A second salt is added to a second aqueous stream to form a second injection stream with an increased concentration of a second ion. The second injection stream is of different composition than the first injection stream and the first injection stream and the second injection stream have substantially the same interfacial tension with a hydrocarbon and substantially the same kinematic viscosity. The first injection stream is injected into the formation at a first time and the second injection stream is injected into the formation at a second time. The first injection stream and second injection stream contact at least some overlapping portion of the formation. Oil is recovered from the overlapping portion of the formation.

Abstract: The present invention relates to a method for the assisted recovery of crude oil from an underground formation, comprising: a) injecting, via at least one injection means in contact with the underground formation containing the crude oil, a liquid containing a mixture of at least: i) a salty aqueous medium, ii) a mixture of two zwitterionic viscosising surfactants or a mixture of two populations of said surfactants having a bimodal characteristic of the narrow distribution of Ri groups as defined below, in a weight content of between 1 and 0.05 wt %, preferably between 0.5 and 0.1 wt %, and more preferably between 0.4 and 0.15 wt %, such that the liquid has an oil/water interface tension of about 10 mN/m (milinewton per meter) or less as measured at room temperature (25° C.) and a viscosity of about 3 cPs or more as measured at a temperature of 80° C.

Abstract: A method for enhancing oil recovery is disclosed. The method includes providing a subsurface reservoir containing hydrocarbons therewithin and a wellbore in fluid communication with the subsurface reservoir. A solution for injection into the reservoir is formed by mixing a composition with at least one non-ionic chemical, at least one polymer, and at least one alkali. The non-ionic chemical can be alcohol alkoxylates such as alkylaryl alkoxy alcohols or alkyl alkoxy alcohols. The solution is solution is clear and aqueous stable when mixed. The solution is injected through the wellbore into the subsurface reservoir.

Abstract: An oil-in-water emulsion that includes a brine continuous phase; and an oleaginous discontinuous phase stabilized by an emulsifier blend, the emulsifier blend comprising: an emulsifier having an HLB greater than 11; and an amphoteric chemotrope is disclosed. Emulsifier blends comprising an emulsifier having an HLB greater than 11 and an amphoteric chemotrope and methods of using emulsifier blends are also disclosed.

Abstract: The present invention is directed to an enhanced oil recovery formulation which comprises: (a) an alkylaromatic sulfonate; (b) an isomerized olefin sulfonate (c) a solvent; (d) a passivator; and (e) a polymer.

Abstract: The present invention relates to a method for the enhanced recovery of oil from an underground formation, in which a viscoelastic aqueous fluid comprising at least one viscosifying zwitterionic surfactant is injected into the said formation and the said fluid is conducted through this formation in order to displace the oil from the formation and to recover it via a different point from that where the viscoelastic aqueous fluid was introduced, characterized in that the said fluid exhibits an amount of a base sufficient to bring its pH to a value of greater than 10, preferably of between approximately 11 and 13.

Abstract: The present invention relates generally to methods and systems for hydrocarbon recovery. More particularly, but not by way of limitation, embodiments of the present invention include methods and systems for enhanced hydrocarbon recovery through secondary recovery operations.

Abstract: A method for producing oil from an underground formation comprising injecting an enhanced oil recovery formulation into a first well in the formation, the enhanced oil recovery formulation comprising a foam; floating the foam on top of the oil, in order to force the oil towards a second well in the formation; and producing the oil and/or gas from the second well.

Abstract: The present invention provides treatment fluids useful for subterranean operations, and more particularly, in at least one aspect, a treatment fluid that comprises a carrier fluid and a cationic surfactant comprising a cationic head group, a polar group attached to the head group, and a hydrophobic group that is either a saturated or unsaturated, branched or straight chain alkyl, and comprises about 6 carbons to about 22 carbons. The treatment fluids of the present invention are at least suitable for use as a remedial treatment for the reduction of existing water blocks, oil blocks, and/or gas condensates.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a synergistic internal breaker composition that contains at least one first internal breaker that may be a mineral oil and a second breaker that may be an unsaturated fatty acid. The internal breakers may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. This combination of different types of internal breakers break the VES-gelled aqueous fluid faster than if one of the breaker types is used alone in an equivalent total amount.

Abstract: An improved method of producing hydrocarbons from a subterranean formation in which a solids-stabilized emulsion (SSE) is formed, the SSE comprising oil as a first liquid, droplets of a second liquid suspended in the oil, and solid particles that are insoluble in both the oil and the second liquid at the conditions of the subterranean formation. The SSE with dissolved gas is injected into the subterranean formation as a drive fluid, and at least a portion of the SSE is placed into one or more area of the subterranean formation having an in situ pressure sufficiently lower than the selected partial pressure to permit evolution of at least a portion of the gas from the oil. Furthermore, a method of making the foamy SSE is also provided.

Abstract: Use of a mixture comprising a surfactant and a cosurfactant in the form of an aqueous solution for flooding underground deposits of hydrocarbons for mobilizing and recovering the hydrocarbons from the underground deposits, the cosurfactant being a substance or a group of substances selected from the following list: an amphiphilic comb polymer having a backbone with two or more side chains attached to the backbone, the side chains differing from one another and/or the side chains differing from the backbone in their amphiphilic character, an amphiphilic polymer having one or more hydrophobic subunits [A2] based on a polyisobutene block, at least 50 mol % of whose polyisobutene macromolecules have terminally arranged double bonds, and one or more hydrophilic subunits [B2], or an amphiphilic polymer having the general structural formula

Abstract: Compositions and methods for oil recovery using a surfactant-less alkaline-polymer system in hard water or hard brine is described in the instant invention. The formulation further includes a chelating agent, an alkaline agent (which can be the same as the chelating agent), and a co-solvent. The formulations as disclosed herein are capable of forming a surfactant in-situ resulting in Winsor Type III micro-emulsions of low interfacial tension.

Abstract: A method for enhancing the production of liquid hydrocarbons from oil-wet, fractured reservoirs comprising injecting a surfactant solution into the reservoir, pressurizing the reservoir, maintaining the pressure, and recovering liquid hydrocarbons. In an embodiment, the method comprises closing production wells for a period to maintain reservoir pressure and surfactant exposure within the matrix.

Abstract: The present invention relates to a process for mineral oil extraction by means of Winsor Type III microemulsion flooding, in which an aqueous surfactant formulation comprising at least one ionic surfactant of the general formula (R1)(R2)—CH—O-(D)n-(B)m-(A)l-XYa? a/b Mb+ is injected through injection boreholes into a mineral oil deposit, and crude oil is withdrawn from the deposit through production boreholes. The invention further relates to ionic surfactants of the general formula, to surfactant formulations, and to a process for preparation thereof.

Abstract: Viscoelastic surfactant (VES) gelled aqueous fluids containing water, a VES in an amount effective to increase the viscosity of the water, and an internal breaker may be useful in removing a residual polymer from a hydraulic fracture. Optionally, a pseudo-crosslinker may be present to further improve the properties related to treatment fluid placement and polymer clean-up. A plurality of aliquots of VES gelled fluid may be injected into a subterranean formation. A stop-start interval may exist between the injection of each aliquot. The VES gelled fluid may contact at least some of the residual polymer in the hydraulic fracture, and a broken fluid is formed once the viscosity of the VES gelled fluid is reduced with the internal breaker. At least a portion of the residual polymer and a majority of the broken fluid may be removed.

Abstract: A method for enhanced oil recovery in an oil-bearing formation having high permeability zones constituting preferential passages for the injected liquid includes the steps of: a) treating the preferential passages by injection into the formation of an aqueous solution based on watersoluble polymers at a concentration such that the viscosity of the aqueous solution is higher than that of the oil, and b) once step a) is completed, an aqueous solution is injected having an identical composition to that used in step a at a lower polymer concentration.

Abstract: In one aspect, embodiments disclosed herein relate to a process for enhanced oil recovery. The process includes the steps of providing an alkali metal borohydride; providing an alkali metal bisulfite; combining the alkali metal borohydride and the alkali metal bisulfite along with water to provide an oxygen-scavenger composition; combining the oxygen-scavenger composition and an aqueous composition to provide an oil recovery solution; and introducing the oil recovery solution into an earthen formation at a pressure to provide for enhanced oil recovery.

Abstract: A process for increasing, on an existing installation, the amount of water-soluble polymer in an emulsion injected into pipelines transporting oil produced at offshore oil wells, includes before injection, diluting the emulsion with fuel oil found on the platform or Floating Production Storage & Offloading unit (FPSO).

Abstract: The present invention relates to processes for tertiary mineral oil production with the aid of a surfactant mixture and to the use of a surfactant mixture for tertiary mineral oil production by means of Winsor type III microemulsion flooding, by injecting a surfactant mixture through at least one aqueous injection borehole into a mineral oil deposit, and withdrawing crude oil from the deposit through at least one production borehole, wherein the surfactant mixture, for the purpose of lowering the interfacial tension between oil and water to <0.1 mN/m, comprises at least the following components: (a) one or more polycarboxylate(s) comprising at least 50 mol % of acrylic acid units and/or methacrylic acid units and/or maleic acid units and/or itaconic acid units or salts thereof, and (b) one or more anionic and/or nonionic surfactant(s).

Abstract: According to one embodiment, a treatment fluid for a well includes: (a) a water-soluble polymer, wherein the water-soluble polymer comprises a polymer of at least one non-acidic ethylenically unsaturated polar monomer; (b) an organic crosslinker capable of crosslinking the water-soluble polymer; (c) an ammonium halide; and (d) water. According to another embodiment, a method for blocking the permeability of a portion of a subterranean formation penetrated by a wellbore is provided, the method including the steps of: (a) selecting the portion of the subterranean formation to be treated, wherein the bottomhole temperature of the portion of the subterranean formation is equal to or greater than 250° F. (121° C.

Abstract: Many methods are provided including a method comprising: providing a surfactant gel having a first viscosity that comprises an aqueous base fluid and a surfactant; providing an ortho ester breaker; contacting the surfactant gel with the ortho ester breaker; allowing the ortho ester breaker to hydrolyze to produce an acid and an alcohol; and allowing the acid and/or the alcohol to interact with the surfactant gel so as to reduce the first viscosity of the surfactant gel to a second viscosity.

Abstract: Methods and systems are provided for enhancing hydrocarbon recovery by the use of treatment fluids comprising low salinity carbonated water. Certain embodiments comprise forming a carbonated aqueous solution formed of either fresh water or low salinity water and introducing the carbonated aqueous solution into a formation to enhance hydrocarbon recovery from the formation. Low salinity brines may be used in lieu of or in combination with the foregoing fresh water. The carbonated water or low salinity carbonated brine may be introduced as a treatment fluid through a secondary well and used to provide a motive force to sweep the hydrocarbons towards one or more production wells. The carbonated water may be produced at a well site through a desalination process that uses naturally occurring brine as its feed.

Abstract: Method for increasing the recovery of crude oil from a reservoir containing at least one porous and permeable subterranean formation wherein the formation includes sandstone rock and at least one mineral that has a negative zeta potential under the reservoir conditions and wherein crude oil and connate water are present within the pores of the formation. The method is carried out by (A) injecting into the formation a slug of an aqueous displacement fluid that displaces crude oil from the surface of the pores of the formation wherein the pore volume (PV) of the slug of the aqueous displacement fluid is at least 0.

Abstract: The invention provides a method for treating a subterranean formation penetrated by a wellbore, the method comprising the steps of formulating a treatment fluid and introducing the treatment fluid through the wellbore. The treatment fluid comprises water; diutan; and a sufficient amount of salt to increase the density of the treatment fluid to at least 8.5 lb/gal, wherein at least 50% by weight of the salt is selected from the group consisting of: bromide salts, non-bromide salts having a higher salting-in effect than bromide according to the Hofmeister series as measured by the salt's effect on the cloud point of poly(ethylene oxide) that has a molecular weight of 4×106, and any combination in any proportion thereof. The invention also provides a treatment fluid for use in a subterranean formation penetrated by a wellbore, the treatment fluid comprising: water; diutan; and a sufficient amount of salt to increase the density of the treatment fluid to at least 8.

Abstract: A system for producing oil and/or gas from an underground formation comprising a first well in the formation; a mechanism to inject a miscible enhanced oil recovery formulation into the first well; a second well in the formation; a mechanism to produce oil and/or gas from the second well; wherein the first well and the second well comprise an interior of the system; a plurality of containment wells exterior to the first well and the second well; and a mechanism to inject a containment agent into the containment wells.

Abstract: The present invention relates to an enhanced oil recovery method using injection of aqueous polymer solutions into the reservoir rock, wherein the following stages are carried out: injecting a first aqueous solution of non-associative hydrophilic polymers into the reservoir in a predetermined proportion so that they adsorb on the reservoir rock, injecting a second aqueous solution of associative polymers into the reservoir for oil recovery, with limited adsorption considering the adsorption of the non-associative polymers of the first solution.

Abstract: The use of a surfactant mixture comprising at least one surfactant having a hydrocarbon radical composed of from 12 to 30 carbon atoms and at least one cosurfactant having a branched hydrocarbon radical composed of from 6 to 11 carbon atoms for tertiary mineral oil extraction.

Abstract: Improved methods of oil and/or gas production by employing mixed surfactants to treat formations comprising multiple rocks. In one embodiment the methods comprise: providing a treatment fluid comprising: an aqueous base fluid, a first surfactant having a charge, a second surfactant having an opposite charge, and a compatibilizer; and introducing the treatment fluid into at least a portion of the subterranean formation.

Abstract: A method of making phenol and alkylphenol ethoxylates non-estrogenic by inserting 1 mole of propylene oxide onto the phenolic group before proceeding with the addition of ethylene oxide or mixtures of ethylene and propylene oxide. The final phenolic products can be further reacted to form sulfates, sulfonates, phosphate esters, condensed alkylphenol alkoxylates and other derivatives of alkylphenol or phenol. Non-estrogenic phenol and alkylphenol alkoxylates and their derivatives have been found to be excellent salt tolerant, high temperature stable surfactants for oil recovery from subterranean reservoirs. These products are also useful in forming emulsions of heavy crude for transportation through pipelines.

Abstract: A method including a) injecting into the formation an aqueous solution containing a polymer and a surfactant to create a organic phase and a aqueous phase, the surfactant being capable of reducing the interfacial tension between the phases to less than 1 dyne/cm; b) recovering a portion of the organic and aqueous phases containing at least a portion of the polymer and surfactant components and a portion of native petroleum surfactants generated in the porous formation; c) adjusting the conditions of the recovered portions to force a portion of the polymer and surfactant from one phase into the other phase by use of chemical, physical, electrical or gravitational means or a combination of said means; d) separating the polymer-and surfactant-containing phase; e) concentrating the polymer and surfactant components in the separated phase; and f) re-injecting at least a portion of the concentrated polymer and surfactant components into the formation.

Abstract: A process for the recovery of oil from subterranean reservoirs by injecting an aqueous fluid containing from about 0.05 to about 2.0% by weight of a surfactant of structure where m+n=1-30 or more, x+y=0-28, EO=oxirane, PO=methyl oxirane, M=H, Na, K, NH3, Amine, Ca, Mg, R and R1 are each separately and independently H, branched or linear alkyl, branched or linear alkenyl, A=aromatic, and, a+b=0 to 30.

Abstract: Recovery of hydrocarbon fluid from low permeability sources enhanced by introduction of a treating fluid is described. The treating fluid may include one or more constituent ingredients designed to cause displacement of hydrocarbon via imbibition. The constituent ingredients may be determined based on estimates of formation wettability. Further, contact angle may be used to determine wettability. Types and concentrations of constituent ingredients such as surfactants may be determined for achieving the enhanced recovery of hydrocarbons. The selection can be based on imbibition testing on material that has been disaggregated from the source formation.

Abstract: The invention discloses a well treatment composition for use in a subterranean formation comprising: a carrier fluid; and a viscoelastic surfactant being present in a concentration of less than about 1.5% by weight. Optionally, the fluid comprises a crosslinked polymer in a thickening amount in the carrier fluid. The invention also discloses a method to increase the viscosity of a fluid, the method comprising: providing a fluid comprising a thickening amount of a crosslinked polymer; adding a viscoelastic surfactant at a given concentration to the fluid; taking the fluid to a given temperature; defining a viscosity profile of the fluid depending of the concentration and the temperature; comparing said viscosity profile to a viscosity profile of the crosslinked polymer fluid alone; and defining an optimum concentration of the viscoelastic surfactant for each temperature.

Abstract: A system for producing oil and/or gas from an underground formation comprising a first array of wells dispersed above the formation; a second array of wells dispersed above the formation; wherein the first array of wells comprises a mechanism to inject a miscible enhanced oil recovery formulation into the formation while the second array of wells comprises a mechanism to produce oil and/or gas from the formation for a first time period; and wherein the second array of wells comprises a mechanism to inject a remediation agent into the formation while the first array of wells comprises a mechanism to produce the miscible enhanced oil recovery formulation from the formation for a second time period.

Abstract: A process for mineral oil production, especially Winsor type III microemulsion flooding, in which an aqueous surfactant formulation which comprises at least one nonionic surfactant having 8 to 30 ethoxy units, which has a polydispersity of from 1.01 to 1.12, and at least one further surfactant is forced through injection wells into a mineral oil deposit and crude oil is removed from the deposit through production wells.

Abstract: A process for mineral oil production, especially Winsor type III microemulsion flooding, in which an aqueous surfactant formulation which comprises at least one alkylpolyalkoxysulfate comprising propoxy groups, and at least one further surfactant differing therefrom is used, is forced through injection wells into a mineral oil deposit and crude oil is removed from the deposit through production wells. The alkylpolyalkoxysulfate comprising propoxy groups is prepared in this case by sulfating an alkoxylated alcohol, the alkoxylated alcohol being prepared by alkoxylating an alcohol using double metal cyanide catalysts or double hydroxide clays.

Abstract: A process for mineral oil production especially Winsor type III microemulsion flooding, in which an aqueous surfactant formulation which comprises at least one nonionic surfactant having 11 to 40 ethoxy units and a hydrophobic radical having 8 to 32 carbon atoms and at least one further surfactant differing therefrom is forced through injection wells into a mineral oil deposit and crude oil is removed from the deposit through production wells.

Abstract: The present invention provides a method for recovering oil from a subterranean reservoir using waterflooding, wherein the flooding fluid used in the waterflooding process comprises water and one or more ionic polyvinyl alcohol copolymers. The use of one or more ionic polyvinyl alcohol copolymers is expected to increase the recovery of oil by improving both the oil/water mobility ratio and the sweep efficiency in reservoirs with a high degree of heterogeneity.

Abstract: A low electrical conductivity water-based wellbore fluid for use in drilling wells through a formation containing a clay which swells in the presence of water, said wellbore fluid that includes an aqueous base fluid; and a polymeric non-ionic tertiary amine is disclosed. Methods of using such fluids are also disclosed.

Abstract: The present invention relates generally to an additive composition for dissolving hydrocarbons. The composition includes a peroxygen compound and surfactant compounds.

Abstract: A microemulsion system is disclosed which comprises a solvent subsystem, a co-solvent subsystem and a surfactant subsystem comprises at least one monoalkyl branched propoxy sulfate anionic surfactant, where the microemulsion system are useful in drilling, producing, remediation, and fracturing application to reduce water blocks and water blocking in formation of a producing formation.

Abstract: A method of oil production is provided. The method includes forming an injection well and a production well. The method also includes pumping a mixture of oxygen and carbon dioxide (CO2) into the injection well. In addition, the method also includes minimizing gravity segregation by providing a relatively high level of CO2 in the mixture.

Abstract: A method and system for remediation of a contaminated subsurface area. The method comprises an infiltration operation in which a surfactant containing a fluorescent dye is injected to various depths in the contaminated area. The surfactant dye may be injected using a gravity feed process or pressure injection. Soil samples are taken at various distances from the injection point. The soil samples are analyzed to determine the radius of influence of the surfactant. Flow rates, flow volumes, and flow paths of the surfactant are determined from the soil samples. A remediation surfactant is injected to encapsulate liquid hydrocarbons in the contaminated area. The contaminant is then extracted from the area using a vacuum extraction system. The extraction system comprises flexible tubing inserted through a port in a well-head cap. The tubing is inserted to an appropriate depth to maintain a predetermined vacuum pressure.

Abstract: The invention provides a method for treating a subterranean formation penetrated by a wellbore, the method comprising the steps of formulating a treatment fluid and introducing the treatment fluid through the wellbore. The treatment fluid comprises water; diutan; and a sufficient amount of salt to increase the density of the treatment fluid to at least 8.5 lb/gal, wherein at least 50% by weight of the salt is selected from the group consisting of: bromide salts, non-bromide salts having a higher salting-in effect than bromide according to the Hofmeister series as measured by the salt's effect on the cloud point of poly(ethylene oxide) that has a molecular weight of 4×106, and any combination in any proportion thereof. The invention also provides a treatment fluid for use in a subterranean formation penetrated by a wellbore, the treatment fluid comprising: water; diutan; and a sufficient amount of salt to increase the density of the treatment fluid to at least 8.

Abstract: Process and a method for enhancing recovery of petroleum from an underground source including injecting into the source, a petroleum displacement agent including fluids and modified liposomes. The liposomes and fluids merge the discrete oil droplets after waterflood into a continuous layer of oil (oil phase) eliminating b-pass of water through oil and employ mobility control through transition of gel phase to liquid crystalline phase.

Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.

Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.

Abstract: There is a method for enhancing the recovery of oil from a reservoir. The method has the step of a) introducing a flooding fluid into the reservoir and b) extracting the oil through a wellbore at a location different than the point of introduction of the flooding fluid into the reservoir. The flooding fluid has water and an amount of one or more non-polymeric viscoelastic surfactants sufficient to provide an interfacial surface tension of about 1 mNm or less and a viscosity of about 10 cps or more. The one or more surfactants is selected from the group of one or more cationic surfactants, one or more zwitterionic surfactants, one or more amphoteric surfactants, one or more anionic surfactants, and combinations thereof.