Abstract: The present invention relates to a surfactant composition containing a cationic surfactant (hereinafter referred to as a compound (A)), one or more compounds (hereinafter referred to as a compound (B)) selected from anionic aromatic compounds and bromide compounds and a cationic polymer (C), wherein compound (A) and (B) are selected when meeting the following condition: a combination of the compounds (A) and (B) ensures that that the viscosity (20° C.) of a solution prepared by mixing an aqueous solution SA of the compound (A) and an aqueous solution SB of the compound (B) in the same ratio is at least two times the viscosity of any one of the aqueous solutions (20° C.) before being mixed.

Abstract: Exemplary embodiments of the cement compositions comprise water, a cement, and a fluid loss control additive, the fluid loss control additive comprising a graft copolymer. The graft copolymer comprises a backbone and at least four grafted monomers selected from the group consisting of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, acrylic acid, vinylphosphonic acid, diallyldimethylammonium chloride, and salts thereof. The backbone of the graft copolymer comprises a humic acid salt. Methods of cementing using exemplary embodiments of the cement compositions are also provided.

Abstract: A fluid comprising a viscous hyposaline aqueous solution of first and second cationic polymers comprising quaternized ammonium groups, wherein the first cationic polymer comprises a hydrophilic base polymer structure and the second cationic polymer comprises a lipophilic base polymer structure, and a method comprising introducing the viscous fluid into an initial first interval of a subterranean formation, and diverting with the viscous fluid a treating fluid from the initial first interval to an initial second interval. The fluid and method are useful to modify a hydrocarbon reservoir formation for improved relative permeability of oil with respect to water to enhance hydrocarbon production from the reservoir.

Abstract: A clay stabilizer which is capable of inhibiting swelling in a wide variety of clay types and is also capable of restoring permeability in formations which have previously been damaged by clay swelling. Amine salts of differing molecular weights configurations and ionic strength are combined to provide transport into micropores, mesopores and macropores in the formation and to effect cationic change therein. A poly quaternary amine having a high to very high charge density is added along with lower molecular weight amine salts to substantially permanently exchange cations with the clay in the formation.

Abstract: Method for enhanced oil recovery consisting in introducing into the injection water a solution containing at least one polymer and at least one surfactant, the surfactant/polymer weight ratio being between 1 and 10 and the surfactant concentration in the solution being higher than 100 ppm (parts per million), characterized in that the said polymer contains at least one hydrophobic cationic monomer.

Abstract: The present invention relates to subterranean treatment fluids, and more particularly, the present invention relates to subterranean treatment fluids comprising relative permeability modifiers and methods for using such subterranean treatment fluids in subterranean operations to reduce the production of water from and stimulate hydrocarbon production in a subterranean formation. In certain embodiments, the methods of the present invention generally comprise the steps of providing a permeability-modifying aqueous treatment fluid comprising a relative permeability modifier and contacting a subterranean formation with the permeability-modifying aqueous treatment fluid. Optionally, the permeability-modifying aqueous treatment fluid may be injected in the subterranean formation at a pressure sufficient to create or enhance at least one fracture therein. In another embodiment, the methods of the present invention further comprise the step of injecting an acidizing treatment into the subterranean formation.

Abstract: The invention relates to the use of quaternary polyamines having formula (I) for the recovery of oil from reservoirs formula (I), wherein n>=1 R1 represents H, CH3, CH2CH3, CnH2n+1 R2 represents H2CHOHCH2, CH2, CH2CH?CH2 R3 represents CH3, CH2CH3, CnH2n+1 R4 represents CH2, CH2CH?CH2 when R2 and R4 are allyl group, they can jointly form aliphatic cyclic structures, the ratio between the carbon atoms and nitrogen atoms (C/N) ranges from 2 to 30.

Abstract: A wellbore sealant composition comprising a cementitious material and a cationic latex into the wellbore.

Abstract: A method and drilling fluid system for providing filtration control during drilling operations using a drilling fluid system comprising water soluble polymer comprising acrylamide monomer, the method comprising: providing a drilling fluid system having effective rheological properties, the drilling fluid system comprising aqueous base consisting essentially of freshwater, a quantity of from about 21 to 58 kg/m3 (7.5 to about 20 pounds per barrel) plugging agent, and an amount of bridging agent comprising water soluble polymer comprising acrylamide monomer which exhibits a 5% by weight Brookfield viscosity in freshwater of from about 50 cP to about 100 cP, and; contacting a subterranean formation with the drilling fluid system and maintaining effective filtration control at concentrations of about 10,000 ppm or less monovalent salt, as demonstrated in the laboratory by producing a HPHT filtrate of 25 cm3/min or less after 30 minutes at about 149° C. (300° F.

Abstract: A process for recovering materials from a subterranean formation, for example in enhanced oil recovery, comprises: (A) (a) (i) selecting a first polymeric material having a repeat unit of formula (A) wherein A and B are the same or different, are selected from optionally-substituted aromatic and heteroaromatic groups and at least one comprises a relatively polar atom or group and R1 and R2 independently comprise relatively non-polar atoms or groups; or (ii) selecting a first polymeric material prepared or preparable by providing a compound of general formula (B) wherein A, B, R1 and R2 are as described above, in an aqueous solvent and causing the groups C?C in said compound to react with one another to form said first polymeric material; (b) selecting a second polymeric material which includes a functional group which is able to react in the presence of said first polymeric material to form a third polymeric material; (c) causing the formation of said third polymeric material by a reaction involving said firs

Abstract: Fluids useful as subterranean treatment fluids, and more particularly, polymeric fluid loss additives, subterranean treatment fluids with improved fluid loss control, and their associated methods of use, are provided. In one embodiment, the methods comprise: providing a treatment fluid that comprises a base fluid, and a polymeric fluid loss control additive that comprises at least a first plurality of polymer molecules having a first average molecular weight, and a second plurality of polymer molecules having a second average molecular weight, wherein the first average molecular weight is different from the second average molecular weight; and introducing the treatment fluid into a subterranean formation.

Abstract: Of the many methods provided herein, one method includes a method of treating an interval of a subterranean formation having a permeability that varies comprising: identifying the interval to be treated; introducing a relative-permeability modifier into the interval, wherein the relative-permeability modifier modifies the interval to have a more uniform effective permeability to water, wherein the relative permeability modifier comprises a water-soluble polymer; and introducing a sealant into the interval, wherein the more uniform effective permeability of the interval allows for a more uniform treatment of the interval by the than would be allowed without treatment of the interval with the relative-permeability modifier.

Abstract: The present invention relates to subterranean treatment fluids, and more particularly, the present invention relates to subterranean treatment fluids comprising relative permeability modifiers and methods for using such subterranean treatment fluids in subterranean operations to reduce the production of water from and stimulate hydrocarbon production in a subterranean formation. In certain embodiments, the methods of the present invention generally comprise the steps of providing a permeability-modifying aqueous treatment fluid comprising a relative permeability modifier and contacting a subterranean formation with the permeability-modifying aqueous treatment fluid. Optionally, the permeability-modifying aqueous treatment fluid may be injected in the subterranean formation at a pressure sufficient to create or enhance at least one fracture therein. In another embodiment, the relative permeability modifier may be provided by appropriate reaction in situ.

Abstract: The present invention relates to subterranean treatment fluids, and more particularly, the present invention relates to subterranean treatment fluids comprising relative permeability modifiers and methods for using such subterranean treatment fluids in subterranean operations to reduce the production of water from and stimulate hydrocarbon production in a subterranean formation. In certain embodiments, the methods of the present invention generally comprise the steps of providing a permeability-modifying aqueous treatment fluid comprising a relative permeability modifier and contacting a subterranean formation with the permeability-modifying aqueous treatment fluid. Optionally, the permeability-modifying aqueous treatment fluid may be injected in the subterranean formation at a pressure sufficient to create or enhance at least one fracture therein. In another embodiment, the relative permeability modifier may be provided by appropriate reaction in situ.

Abstract: Exemplary embodiments of the cement compositions comprise water, a cement, and a fluid loss control additive, the fluid loss control additive comprising a graft copolymer. The graft copolymer comprises a backbone and at least four grafted monomers selected from the group consisting of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, acrylic acid, vinylphosphonic acid, diallyldimethylammonium chloride, and salts thereof. The backbone of the graft copolymer comprises a humic acid salt. Methods of cementing using exemplary embodiments of the cement compositions are also provided.

Abstract: A method for treating a subterranean formation penetrated by a wellbore utilizes forming at least one of a treatment fluid A and a treatment fluid B. The treatment fluid A comprises an aqueous carrier fluid, a first relative permeability modifier (RPM) polymer, a water-soluble viscosifying polymer and a crosslinking agent capable of crosslinking the viscosifying polymer at a pH of from about 3 to about 5. The treatment fluid B comprises a fresh-water carrier fluid and a second relative permeability modifier (RPM), and optionally an amount of fibers. At least one of the treatment fluids A and B is introduced into the formation through the wellbore.

Abstract: An exemplary method of the present invention for performing an injection operation includes providing a water-soluble relative permeability modifier, introducing the water-soluble relative permeability modifier into a subterranean formation; and injecting an aqueous injection fluid into the subterranean formation after introducing the water-soluble relative permeability modifier. An exemplary permeability-modifying injection fluid of the present invention contains water-soluble relative permeability modifier. The water-soluble relative permeability modifiers of the present invention include hydrophobically modified water-soluble polymers, hydrophilically modified water-soluble polymers, and water-soluble polymers without hydrophobic or hydrophilic modification.

Abstract: Compositions for increasing the thermal and pressure stability of well fluids viscosified using viscoelastic surfactants, the compositions including an effective amount of an oligomeric or polymeric compound that has a thermally stable backbone structure and at least one pendent viscoelastic surfactant functional group. Preferred compositions for increasing the stability of well fluids viscosified using monomeric viscoelastic surfactants include an effective amount of an oligomeric or polymeric compound that has a thermally stable backbone structure and a multiplicity of pendent viscoelastic surfactant functional groups attached to said backbone structure through relatively long hydrocarbon chains, 1 to 18 carbons in length.

Abstract: A water based drilling fluid for use in drilling a subterranean well through a subterranean formation that swells in the presence of water, the drilling fluid is formulated to include: an aqueous based continuous phase; a weight material; an optional shale hydration inhibition agent and a shale encapsulator. The shale encapsulator has the formula: in which x and y have a value so that the molecular weight of the cation is in the range of about 10,000 to about 200,000 AMU; A is selected from C1-C6 alkyl, C2-C6 ether or C2-C6 amide; R, R? and R? are independently selectable C1-C3 alkyl; and B? is a charge balancing anion to the quatenary amine. The shale hydration inhibition agent and the shale encapsulator may be present in sufficient concentrations to reduce the swelling of the subterranean formation in the presence of water.

Abstract: A method of forming a subterranean well and a method of reducing the swelling of shale clay during the drilling of the subterranean well. The method features the use of a water based drilling fluid, wherein the drilling fluid is formulated to include: an aqueous based continuous phase; a weight material; an optional shale hydration inhibition agent and a shale encapsulator. The shale encapsulator has the formula: in which x and y have a value so that the molecular weight of the cation is in the range of about 10,000 to about 200,000 AMU; A is selected from C1-C6 alkyl, C2-C6 ether or C2-C6 amide; R, R?and R?are independently selectable C1-C3 alkyl; and B?is a charge balancing anion to the quaternary amine. The shale hydration inhibition agent and the shale encapsulator may be present in sufficient concentrations to reduce the swelling of the subterranean formation in the presence of water.

Abstract: The invention concerns an aqueous viscoelastic fracturing fluid for use in the recovery of hydrocarbons. According to the invention, the fluid comprises a cleavable viscoelastic surfactant and a hydrophobically-modified polymer, wherein the cleavable surfactant comprises a head group and a hydrophobic tail of at least 18 carbon atoms connected through a degradable acetal, amide, ether or ester bond and wherein the concentration of the hydrophobically-modified polymer is comprised between its overlap concentration c* and its entanglement concentration ce.

Abstract: The invention concerns an aqueous viscoelastic fracturing fluid for use in the recovery of hydrocarbons. According to the invention, the fluid comprises a viscoelastic surfactant and a hydrophobically-modified polymer wherein the concentration of the hydrophobically-modified polymer is comprised between its overlap concentration c* and its entanglement concentration ce.

Abstract: Exemplary embodiments provide treatment fluids for treating a subterranean formation to improve gas production therefrom. Exemplary embodiments of the treatment fluids comprise a base fluid and a cationic polyorganosiloxane, wherein the cationic polyorganosiloxane comprises at least two cationic quaternary ammonium groups.

Abstract: A formulation containing a copolymer derived from a cationic monomer effectively inhibits and controls the formation of inorganic scales. Suitable copolymers include those comprising an acrylamide unit and a quaternary ammonium salt group, and optionally an acrylate and/or nitrogen heterocyclic monomer including those wherein the quaternary ammonium salt is a unit of the formula: wherein R is methyl or hydrogen; R4 is a C1 to C6 alkyl group, optionally substituted with halogen, hydroxyl and alkoxy groups, X is halogen; and R1, R2 and R3 are independently selected from the group consisting of alkyl and alkoxy groups. Suitable nitrogen heterocyclic compounds include N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, N-vinylcaprolactam, N-vinylimidazole and N-vinylpyridine.

Abstract: A clayish subterranean formation, such as may be encountered in rock surrounding a well bore during hydrocarbon recovery operations may be stabilized with relatively high molecular weight acid ammonium salts of an imide of polymaleic anhydride. The salts may be unneutralized or partially neutralized. The invention is particularly relevant to hydraulic fracturing fluids used in enhanced oil recovery. The compositions herein are made in the presence of a reactive solvent, such as a polyalkylene glycol, e.g. polyethylene glycol. The compositions of this invention are more environmentally friendly than some current technology.

Abstract: A composition includes water having a salinity of at least 1 ppt, at least one hydrophilic polymer containing primary (—NH2) and/or secondary (—NHR) amine groups and at least one saccharide containing a reducible function. A method of changing the permeability of a subterranean formation includes the step of injecting into a subterranean formation a composition comprising water, at least one hydrophilic polymer containing at least two groups which are independently the same or different a primary amine group or a secondary amine group and at least one saccharide containing a reducible function.

Abstract: A formulation containing a copolymer derived from a cationic monomer effectively inhibits and controls the formation of inorganic scales. The formulation has particular application in the removal of zinc sulfide and iron sulfide scales formed when zinc bromide brines are used as completion fluids. The copolymer exhibit high solubility in high-density brines, such as zinc bromide brines. The polymers may be introduced into an oil or gas well as a portion of a carrier fluid or with brine. The preferred copolymer for use in the invention contains an acrylamide unit and a diallyldimethylammonium salt and, optionally, an acrylic acid or a salt thereof. The weight average molecular weight of such inhibitor copolymers is generally between from about 500,000 to about 5,000,000.

Abstract: Water soluble nonionic friction reducers and added to coacervate gels having excellent shear viscosities and other properties. A preferred gel comprises poly diallyl dimethyl ammonium chloride, a lesser amount of sodium lauryl sulfonate, and lauryl alcohol. Excellent friction reducing properties are manifested; a particularly practical use for the compositions is in subterranean formation fracturing.

Abstract: A water based drilling fluid for use in drilling a subterranean well through a subterranean formation that swells in the presence of water, the drilling fluid is formulated to include: an aqueous based continuous phase; a weigh material; a shale encapsulator and an optional shale hydration inhibition agent. The shale encapsulator has the formula: which x and y have a value so that the molecular weight of the cation is in the range of about 10,000 to about 200,000 AMU; A is selected from C1–C6 alkyl, C2–C6 ether or amide; R, R? and R? are independently selectable C1–C3 alkyl; and B? is a charge balancing anion to the quaternary amine. The shale encapsulator and the optional shale hydration inhibition agent may be present in sufficient concentrations to reduce the swelling of the subterranean formation in the presence of water.

Abstract: A process is described for reducing the production of water in oil wells which comprises the injection into the formation around the well of an aqueous solution of one or more polymers selected from those having general formula (I), wherein: n ranges from 0.70 to 0.98; m ranges from 0.30 to 0.02; n+m=1; X1 and X2, the same or different, are selected from H and CH3; R1, R2, R3, the same or different, are selected from C1–C10 monofunctional hydrocarbyl groups; and x ranges from 2 to 5.

Abstract: A formulation containing a copolymer derived from a cationic monomer effectively inhibits and controls the formation of inorganic scales. The formulation has particular application in the removal of zinc sulfide and iron sulfide scales formed when zinc bromide brines are used as completion fluids. The copolymer exhibit high solubility in high-density brines, such as zinc bromide brines. The polymers may be introduced into an oil or gas well as a portion of a carrier fluid or with brine. The preferred copolymer for use in the invention contains an acrylamide unit and a diallyldimethylammonium salt and, optionally, an acrylic acid or a salt thereof. The weight average molecular weight of such inhibitor copolymers is generally between from about 500,000 to about 5,000,000.

Abstract: Compositions for increasing the thermal and pressure stability of well fluids viscosified using viscoelastic surfactants, the compositions including an effective amount of an oligomeric or polymeric compound that has a thermally stable backbone structure and at least one pendent viscoelastic surfactant functional group. Preferred compositions for increasing the stability of well fluids viscosified using monomeric viscoelastic surfactants include an effective amount of an oligomeric or polymeric compound that has a thermally stable backbone structure and a multiplicity of pendent viscoelastic surfactant functional groups attached to said backbone structure through relatively long hydrocarbon chains, 1 to 18 carbons in length.

Abstract: A process for stimulating a formation is disclosed wherein a diverting fluid is used to divert an acid treatment package from a high permeability or damaged portion of a formation to a low permeability or undamaged portion of a formation. The fluid, which preferably forms vesicles, comprises at least one surfactant, at least one quaternary amine polyelectrolyte, water, and a non-aqueous solvent.

Abstract: A composition of matter for use in stablizing shale formations in earth boreholes comprising polymeric products, e.g., polymers of a dialkyl aminoalkyl methacrylate, which can optionally be quaternized with an alkyl halide to produce drilling fluid additives which stablize borehole formations containing reactive clays in the presence of an aqueous medium.

Abstract: A process is described for reducing the production of water in oil wells, with temperatures of up to (90° C.), which comprises the injection in the formation around the well of an aqueous solution of one or more polymers selected from those having general formula (I) wherein: n ranges from (0.40) to (0.70), preferably from (0.5) to (0.65); m ranges from (0.15) to (0.65), preferably from (0.3) to (0.5); p ranges from (0.02) to (0.20), preferably from (0.05) to (0.

Abstract: Disclosed is a copolymer useful for preparing acid gels comprising a copolymer having a copolymer backbone, the copolymer having a general formula: wherein: (a) A is an H or other terminating group; (b) R1 is an OH or NH2; (c) R2 is an O or NH; (d) Z is an integer having a value of from 1 to 4; (e) X and Y are present in a ratio (X:Y) of from 3:2 to 4:1; (f) structures I and II are present as blocks or randomly distributed along the copolymer backbone; and wherein the copolymer has a molecular weight of from about 1,000,000 to about 10,000,000.

Abstract: The use of a hydrophobically modified water soluble polymer is described capable of being chemically cross-linked so as to produce a stable gel for blocking a water-bearing formation from a hydrocarbon-producing well. The polymer is essentially linear having hydrophilic side groups located at random positions along its backbone.

Abstract: A method of reducing friction resulting from turbulent flow in an aqueous fracturing fluid in an oil field fracturing process comprising adding to the aqueous fracturing fluid an effective friction-reducing amount of one or more dispersion polymers, wherein the dispersion polymer is composed of from about 5 to about 95 mole percent of one or more nonionic monomers and from about 95 to about 5 mole percent of one or more cationic or anionic monomers and has a molecular weight of at least 100,000.

Abstract: The present invention relates to methods, aqueous treating fluids and friction pressure reducers for the treating fluids. A treating fluid of the invention comprises water and a non-toxic environmentally acceptable friction pressure reducer comprising a mixture of a copolymer of acrylamide and dimethylaminoethyl acrylate quaternized with benzyl chloride and a stabilizing and dispersing homopolymer of ethanaminium,N,N,N-trimethyl-2-[(1,oxo-2-prbpenyl)oxy]-chloride.

Abstract: A well fracturing fluid comprising one or more anionic viscoelastic surfactants and one or more polymers is described. The fluids can contain an aqueous or non-aqueous fluid and/or buffer for adjusting the pH of the fracturing fluid. The well service fluid can used as a fracturing fluid in order to control water production from a well, while simultaneously increasing the oil production from the well.

Abstract: Clay is stabilized in the drilling of wells and other formation treatment for hydrocarbon production by the addition to the drilling or other fluid fluid of potassium formate together with a cationic formation control additive.

Abstract: What is disclosed is the preparation and use of synthetic water soluble copolymers useful in modifying the water permeability characteristics of subterranean hydrocarbon producing formations. The copolymers are in the form of dilute, pumpable, homogeneous, aqueous solutions and comprise a crosslinked synthetic copolymerizate with intramolecular and intermolecular crosslinking in a non-gelled state and a molecular size/shape corresponding to a K-value of 220-450.

Abstract: The invention concerns a water based foaming composition and the method of making it. The composition is optimized in that it contains a surfactant specifically selected according to the polymer also present in the composition. The surfactant and the polymer are selected so that they are oppositely charged. The invention is very useful in drilling or treating wells.

Abstract: A subterranean formation is treated by introducing a fracturing treatment composition comprising a polymer treatment fluid containing a dispersion of hydrophilic water swellable particles into the formation. The water swellable particles comprise synthetic polymers that are crosslinked so that they are water insoluble, but capable of swelling in the presence of relatively small amounts of water. When used with treatment fluids containing at least a small amount of water, the particles swell and reduce fluid loss to the formation during the treatment. When used during a hydraulic fracturing treatment of a hydrocarbon bearing formation, the particles may also reduce or eliminate water production following the fracturing treatment by restricting the extension of a fracture into water-bearing formations, and/or by restricting the flow of fluids from water-bearing areas.

Abstract: A composition is provided which comprises a polymer comprising repeat units derived from an unsaturated amide, an N-vinyl lactam, and optionally, a vinyl acid. Also provided is a water-based fluid composition which can be used as drilling fluid wherein the composition comprises calcium chloride and the polymer. Further providing is a process for using a water-based fluid wherein the process comprises contacting a subterranean formation with the water-based fluid composition disclosed above to effect the control of fluid loss of the water-based fluid composition.

Abstract: Cationic polymer-containing gels are stable at elevated temperatures in soft and hard waters.

Abstract: The present invention provides a method for reducing the amount of water produced from a subterranean formation as a result of stimulation of the subterranean formation. The method comprises the introduction of a gelled fluid to initiate a fracture in a formation, introduction of a first and second reactive polymer which leak-off into the formation along the fracture and which are capable of subsequently reacting together to form a reaction product which selectively reduces the permeability of the formation to water flow through the formation into the fracture and introduction of a crosslinked gelled fluid to extend the fracture into the formation and facilitate the introduction of a propping agent into the created fracture. The reactive polymers react in situ to form a reaction product that binds to the formation in such a manner that the flow of water is selectively retarded through the matrix while the flow of oil is substantially unaffected.

Abstract: The present invention provides compositions useful for viscosifying aqueous fluids, methods for making them and methods for using them. In one aspect of the invention, inventive compositions comprise a prehydrating alcohol having at least two hydroxyl groups and having a molecular weight of from about 60 to about 600; an inorganic salt; and a polymer. In a preferred aspect of the invention, the viscosifier composition additionally comprises a solvent having a molecular weight of from about 75 to about 1000. According to another aspect of the invention, inventive compositions comprise a prehydrating alcohol; an inorganic salt; and a polymer; and the composition is essentially free from water. Inventive compositions find advantageous use in viscosifying fluids utilized in subterranean drilling activities such as, for example, drilling, drill-in, completion, hydraulic fracturing, work-over, packer, well treating, testing, spacer, or hole abandonment fluids.

Abstract: Cationic polymer-containing gels are stable at elevated temperatures in soft and hard waters.

Abstract: Compositions and methods for modifying the permeability of subterranean formations are shown. The compositions and methods generally comprise forming a dispersion of water swellable crosslinked polymer particles, adding the dispersion to a carrier fluid to form a treatment fluid, and injecting the treatment fluid into the subterranean formation. The particles are made by polymer emulsion or microemulsion processes, resulting in particles that are much smaller in size than that of the formation pore strictures. Upon injection, the particles become trapped in the formation, and upon flowback of water, the particles swell in size and adsorb onto the formation, forming a film and restricting further fluid flow.