Abstract: The present invention relates to a hydraulic fracturing fluid composition comprising a homogeneous non-aqueous organic phase mixture which mixture comprises a base fluid and one or more surfactants.

Abstract: Coacervate gels having excellent shear viscosities and other properties are made with anionic or cationic polymers, a smaller amount of a surfactant having a charge opposite that of the polymer, and a hydrophobic alcohol and an effective amount of a phosphorus-containing compound sufficient to increase the viscosity of coacervate gels up to 3 times as compared to the gels in the absence of the phosphorus-containing compound. The Zeta Potential of the gel is maintained at an absolute value of at least 20. Optional gel promoting additives include betaines and amine oxides. A preferred gel comprises poly diallyl dimethyl ammonium chloride, a lesser amount of sodium lauryl sulfonate, and lauryl alcohol. The gels are particularly useful in well drilling fluids and well fracturing fluids.

Abstract: An invert emulsion drilling fluid, and a method for the use thereof in drilling wellbores, with good rheological properties at high temperatures and pressures. One embodiment of the drilling fluids is free of organophilic clays and lignites, free of calcium chloride, and comprises glycerol in the internal phase, and a suspension agent comprising a combination of a fatty dimer diamine and a short chain acid, such as citric acid. In one embodiment, the base oil for the emulsion is a paraffin and/or mineral oil. The drilling fluids provide good rheological properties including good suspension of drill cuttings.

Abstract: Of the many embodiments provided herein, one embodiment includes a method comprising: providing a drilling fluid comprising: an aqueous fluid; and a surfactant; and drilling a well bore in a subterranean formation comprising an oleaginous fluid using the drilling fluid, wherein the surfactant forms a micelle within the well bore; and removing an oil block in the formation.

Abstract: Coacervate gels having excellent shear viscosities and other properties are made with anionic or cationic polymers, a smaller amount of a surfactant having a charge opposite that of the polymer, and a hydrophobic alcohol and an effective amount of a phosphorus-containing compound sufficient to increase the viscosity of coacervate gels up to 3 times as compared to the gels in the absence of the phosphorus-containing compound. The Zeta Potential of the gel is maintained at an absolute value of at least 20. Optional gel promoting additives include betaines and amine oxides. A preferred gel comprises poly diallyl dimethyl ammonium chloride, a lesser amount of sodium lauryl sulfonate, and lauryl alcohol. The gels are particularly useful in well drilling fluids and well fracturing fluids.

Abstract: Fluids comprising oil; and an organophilic clay comprising a smectite clay modified by reaction with a protonated amphoteric surfactant. The smectite clay may be montmorillonite, beidellite, nontronite, or a combination thereof. The protonated amphoteric surfactant may be cetyl/myristyl amine oxide, a stearyl amine oxide, a stearyl betaine, or a combination thereof. In some cases, the fluid may also include water and/or a solid reactive metal.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities affected (increased or reduced) by the indirect or direct action of a composition that contains at least one fatty acid that has been affected, modified or reacted with an alkali metal halide salt, an alkaline earth metal halide salt, and/or an ammonium salt and a water soluble base. The composition containing the resulting saponification product is believed to either act as a co-surfactant with the VES itself to increase viscosity and/or possibly by disaggregating or otherwise affecting the micellar structure of the VES-gelled fluid. In a non-limiting instance, a brine fluid gelled with an amine oxide surfactant has its viscosity broken with a composition containing naturally-occurring fatty acids in canola oil reacted with a water soluble base such as NaOH, KOH, NH4OH, and the like with an alkali halide salt such as CaCl2, MgCl2, NaCl, NH4Cl and the like.

Abstract: Drilling fluids are provided that comprise an organophilic clay treated with a quaternary ammonium surfactant having an amide linkage. The quaternary ammonium surfactant may comprise a compound generally represented by the following formula: where M? is an anion such as a chloride, methyl sulfate, bromide, acetate, or iodide ion; R1 is an alkyl group such as a saturated hydrocarbon with 10 or more carbons; R2, R3, and R4 are the same or different alkyl groups such as a methyl, ethyl, or benzyl group, and x is greater than or equal to 1. The organophilic clay treated in this manner is substantially biodegradable. In embodiments, the drilling fluids comprise the foregoing organophilic clay, an oil-based fluid and a weighting agent. In still more embodiments, the drilling fluids comprise the foregoing organophilic clay, an invert emulsion, an emulsifier, and a weighting agent.

Abstract: A method of reducing wear in a cutting head of a tunnel boring machine, by means of the addition at the cutting head of a foamed aqueous liquid composition, which comprises a foaming agent and a lubricant, the lubricant being selected from the group consisting of high molecular weight polyethylene oxides and bentonite. Preferred foaming agents are anionic and nonionic surfactants. Wear rates of cutting elements of TBMs boring in hard rock are considerably reduced. A wear-reducing foamable concentrate is also described.

Abstract: The present invention provides aqueous viscoelastic compositions comprising a cleavable surfactant and possibly also an electrolyte. The cleavable surfactants useful in the present invention comprise at least one weak chemical bond, which is capable of being broken under appropriate conditions, to produce oil soluble and water soluble products typically having no interfacial properties and surface activity compared with the original surfactant molecule. Further, the rheological properties of the aqueous viscolelastic composition are usually altered upon cleavage of the cleavable surfactant generally resulting in the elimination of the viscofying, viscoelastic and surfactant properties of the composition. Aqueous viscoelastic compositions in accordance with the present invention are suitable for use in oil-field applications, particularly for hydraulic fracturing of subterranean formations. Thus, the present invention also relates to a wellbore service fluid and a method of fracturing a subterranean formation.

Abstract: Drilling fluids are provided that comprise an organophilic clay treated with a quaternary ammonium surfactant having an amide linkage. The quaternary ammonium surfactant may comprise a compound generally represented by the following formula: where M? is an anion such as a chloride, methyl sulfate, bromide, acetate, or iodide ion; R1 is an alkyl group such as a saturated hydrocarbon with 10 or more carbons; R2, R3, and R4 are the same or different alkyl groups such as a methyl, ethyl, or benzyl group, and x is greater than or equal to 1. The organophilic clay treated in this manner is substantially biodegradable. In embodiments, the drilling fluids comprise the foregoing organophilic clay, an oil-based fluid and a weighting agent. In still embodiments, the drilling fluids comprise the foregoing organophilic clay, an invert emulsion, an emulsifier, and a weighting agent.

Abstract: Well treatment is disclosed that includes injecting a well treatment fluid with insoluble polyol polymer such as polyvinyl alcohol (PVOH) dispersed therein, depositing the insoluble polymer in the wellbore or an adjacent formation, and thereafter dissolving the polymer by reducing salinity and/or increasing temperature conditions in the environment of the polymer deposit. The method is disclosed for filter cake formation, fluid loss control, drilling, hydraulic fracturing and fiber assisted transport, where removal of the polyol at the end of treatment or after treatment is desired. The method is also disclosed for providing dissolved polyol as a delayed breaker in crosslinked polymer viscosified systems and viscoelastic surfactant systems. Also disclosed are well treatment fluids containing insoluble amorphous or at least partially crystalline polyol, and a PVOH fiber composition wherein the fibers are stabilized from dissolution by salinity.

Abstract: Compounds of the formula H(CH2)zCOO—[C2H4O]xCyH2y+1 where z is 0-2, x is an integer from 1 to 5 and y is an integer from 4-9 are used as emulsion breakers and defoamers in formation treatment fluids in the recovery of hydrocarbons from subterranean formations. A preferred material has the formula HCOO—[C2H40]3C6H7.

Abstract: The present invention generally relates to aqueous, acidic compositions thickened with an amidoamine oxide gelling agent and/or viscoelastic surfactant of the general formula I: wherein R1 is a saturated or unsaturated, straight or branched chain aliphatic group of from about 7 to about 30 carbon atoms, R2 is a divalent alkylene group of 2–6 carbon atoms which may be linear or branched, substituted or unsubstituted, and R3 and R4 are independently C1–C4 alkyl or hydroxyalkyl groups or together they form a heterocyclic ring of up to six members, and R5 is hydrogen or a C1–C4 alkyl or hydroxyalkyl group. The aforementioned gelling agents advantageously provide gels that do not undergo phase separation over extended periods of time and exhibit high heat stability. The thickened acid gels of the invention have applications in household and industrial cleaners and degreasers, oilfield stimulation applications and the like.

Abstract: It has been discovered that fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a biochemical agent, such as bacteria, fungi, and/or enzymes. The biochemical agent may directly attack the VES itself, or some other component in the fluid that produces a by-product that then causes viscosity reduction. The biochemical agent may disaggregate or otherwise attack the micellar structure of the VES-gelled fluid. The biochemical agent may produce an enzyme that reduces viscosity by one of these mechanisms. A single biochemical agent may operate simultaneously by two different mechanisms, such as by degrading the VES directly, as well as another component, such as a glycol, the latter mechanism in turn producing a by-product (e.g. an alcohol) that causes viscosity reduction. Alternatively, two or more different biochemical agents may be used simultaneously.

Abstract: Compounds of the formula H(CH2)zCOO—[C2H4O]xCyH2y+1 where z is 0-2, x is an integer from 1 to 5 and y is an integer from 4-9 are used as emulsion breakers and defoamers in formation treatment fluids in the recovery of hydrocarbons from subterranean formations. A preferred material has the formula HCOO—[C2H4O]3C6H7.

Abstract: Improved methods of generating gas in and foaming aqueous well fluids introduced into a subterranean zone are provided. A method of the invention includes the steps of combining with an alkaline aqueous well fluid one or more gas generating chemicals and a mixture of foaming and foaming stabilizing surfactants so that the gas generating chemical or chemicals react with the alkaline aqueous well fluid and gas and foam are formed in the well fluid while it is being pumped, and then pumping the well fluid into the subterranean zone.

Abstract: A method for controlling the rheology of aqueous systems, particularly for those intended for underground use, includes injecting an aqueous viscoelastic fluid containing a surfactant gelling agent into the system. The viscoelastic surfactant composition of the invention comprises, as a gelling agent, at least one fatty aliphatic amidoamine oxide in a glycol solvent. The composition also maintains the levels of free fatty acid and free amine within critical parameters in order to achieve superior performance. The additives may be incorporated in the viscoelastic fluid to tailor its use in stimulation fluids, drilling muds, fracture fluids, and in applications such as permeability modification, gravel packing, cementing, and the like.

Abstract: A method for controlling the rheology of aqueous systems, particularly for those intended for underground use, includes injecting an aqueous fluid containing a surfactant gelling agent into the system. The surfactant gelling agents are, for example, fatty aliphatic amidoamine oxides, salts of an alkoxylated monoamine with an aromatic dicarboxylic acid, and salts of an alkyldiamine with an aromatic dicarboxylic acid. The surfactant gelling agents can be adsorbed onto particulate supports to facilitate delivery of the gelling agent. The additives may be incorporated in the viscoelastic fluid to tailor its use in hydraulic fluids, drilling muds, fracture fluids, and in applications such as permeability modification, gravel packing, cementing, and the like.

Abstract: The invention relates to a gel made of apolar medium including:an apolar medium,a "multichain" liquid surface-active agent in acidic form, soluble or dispersible in the said apolar medium,an agent for neutralizing the said "multichain" surface-active agent,from 0.2 to 5 molecules of water per molecule of "multichain" surface-active agent,optionally at least one emulsifying agent and/or a solid filler which is soluble or insoluble in the apolar medium.This gel may be employed for the formulation of water-based drilling fluids.

Abstract: Aqueous structured surfactants, e.g., lamellar, or preferably spherulitic systems optionally containing suspended solids are used as functional fluids, such as drilling fluids, cutting fluids, hydraulic fluids, heat transfer fluids, construction muds and lubricants. A composition consisting essentially of: water; a surfactant or mixture of surfactants present in a concentration sufficient to form a mobile spherulitic or dispersed lamellar phase in the absence of an electrolyte; and a substantially water insoluble functional material, suspended in the composition, the composition being substantially free from electrolyte.

Abstract: Water-in-oil emulsions are disclosed wherein the continuous phase comprises an oil and an emulsifier and the discontinuous phase comprises an aqueous solution of a hydroxylamine or an at least partially neutralized hydroxylamine salt.

Abstract: 2-(2-bromo-2-nitroethenyl)-furan can be used as an antimicrobial in broad spectrum of uses. A novel process for preparing 2-(2-bromo-2-nitroethenyl)-furan has been found in which furfural is reacted with bromonitromethane using a primary amine or primary amine salt as a catalytic agent to produce an intermediate product which is dehydrated in the presence of acid to the desired product. An antimicrobial composition comprising 2-(2-bromo-2-nitroethenyl)-furan and a carrier is also disclosed.

Abstract: A method for controlling the rheology of aqueous systems, particularly for those intended for underground use, includes injecting an aqueous fluid containing a surfactant gelling agent into the system. The surfactant gelling agents are, for example, fatty aliphatic amidoamine oxides, salts of an alkoxylated monoamine with an aromatic dicarboxylic acid, and salts of an alkyldiamine with an aromatic dicarboxylic acid. The surfactant gelling agents can be absorbed onto particulate supports to facilitate delivery of the gelling agent. The additives may be incorporated in the viscoelastic fluid to tailor its use in hydraulic fluids, drilling muds, fracture fluids, and in applications such as permeability modification, gravel packing, cementing, and the like.