Abstract: A method for inhibiting hydrate formation in a hydrocarbon flow by adding an amount of a dendrimeric compound effective to inhibit formation of hydrates at conduit temperatures and pressures, and flowing the mixture containing the dendrimeric compound and any hydrates through the conduit. Preferably, a hyperbranched polyester amide is used as hydrate formation inhibitor compound.

Abstract: A method of electrically logging subterranean wells using a conductive double emulsion fluid includes a miscible combination of an oleaginous fluid, an emulsifier capable of forming a microemulsion, an emulsifier capable of forming an invert emulsion, and an electrolytic salt. A microemulsion is the continuous phase of an invert emulsion. The electrolytic salt or brine of the salt is present in a concentration sufficient to permit the electrical logging of the subterranean well. The fluid may additionally contain a polar organic solvent and a carbon dioxide buffer. The polar organic solvent may be an oil soluble glycol or glycol ether such as ethylene glycol, diethylene glycol, propylene glycol, polypropylene glycol, and the like.

Abstract: A fluid having utility in subterranean wells is formulated to include: an oleaginous fluid; and a solids tolerance agent having the formula: in which R is a C6 to C20 aliphatic group and R′ is a C2 to C6 aliphatic group and x has a value from about 1 to about 10. Preferably R′ is selected from ethyl and isopropyl and R is an unsaturated aliphatic group. The fluid is formulated such that the oleaginous fluid is from about 30% to about 99% by volume of said fluid. In one illustrative embodiment, the oleaginous fluid is composed from about 5% to about 100% by volume of the oleaginous fluid of a material selected from a group consisting of diesel oil, mineral oil, synthetic oil, esters, ethers, acetals, di-alkylcarbonates, olefins, and combinations of these and similar fluids. A non-oleaginous fluid may also be included in the formulation that is from about 1% to about 70% by volume of said fluid.

Abstract: Non-aqueous base wellbore fluids characterized by enhanced electrical conductivity due to formulation with specified ionic liquids are disclosed. Drilling, completion, and workover methods utilizing the wellbore fluids are also disclosed.

Abstract: An additive for inhibiting the formation of gas hydrates in connection with hydrocarbon production and transportation comprising the water-soluble polymers comprising structural elements of the formula wherein each R is independently H or C1-C5-alkyl; X is H, an alkaline or earth alkaline metal or a quaternary ammonium group; R1 is H or C1-C18-alkyl; and R2 is C1-C18-alkyl; and wherein the alkyl groups represented by R1 and R2 optionally carry a hydroxy or amino substituent; and, optionally, a minor proportion of structural elements of the formula  wherein R, R1, R2 and X may have the meaning as above, and Alk is a C1-C5-alkylene chain.

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: An additive for inhibiting the formation of gas hydrates in connection with hydrocarbon production and transportation comprising the water-soluble polymers comprising structural elements of the formula wherein each R is independently H or C1-C5-alkyl; X is H, an alkaline or earth alkaline metal or a quaternary ammonium group; R1 is H or C1-C18-alkyl; and R2 is C1-C18-alkyl; and wherein the alkyl groups represented by R1 and R2 optionally carry a hydroxy or amino substituent; and, optionally, a minor proportion of structural elements of the formula wherein R, R1, R2 and X may have the meaning as above, and Alk is a C1-C5-alkylene chain.

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: A composition and a process for using the composition for applications in a subterranean formation are provided. The composition comprises a clay, a polymer, and a liquid. The polymer comprises repeat units derived from a nitrogen-containing olefinic monomer and optionally an olefinic comonomer. The composition can be used as or in drilling fluids, workover fluids, completion fluids, or combinations of any two or more thereof.

Abstract: The present invention relates to an oil-based drilling fluid, a continuous phase for an oil-based drilling fluid, and additives for an oil-based drilling fluid. The drilling fluid, the continuous phase of the drilling fluid, and the additives for the oil-based drilling fluid are characterized by non-fluorescence (defined as a fluorescence intensity of 800 or less) when exposed to ultraviolet light. The continuous phase of the drilling fluid is composed of synthetic hydrocarbons selected from the group consisting of oligomers synthesized from one or more alphaolefins containing a C.sub.2 to C.sub.14 chain length, wherein the oligomers have an average molecular weight of from 120 to 100, and additives. The additives of the continuous phase include surfactants, wetting agents and/or emulsifiers.

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: The present invention provides improved quaternary ammonium compounds useful as metal corrosion inhibitors in aqueous acid solutions, methods of preparing the compounds, metal corrosion inhibited aqueous acid solutions containing the compounds and methods of protecting metal surfaces from acid corrosion using the compounds. The compounds are prepared by contacting the still bottoms residue produced in the distillation of quinoline from coal tar with oxygen to oligomerize aromatic amines contained therein and then reacting the oligomerized amines with a benzylhalide.

Abstract: Herbicidal 1-cyclopropyl tetrazolinones of the formula ##STR1## wherein X represents C.sub.1-3 alkyl, C.sub.2-4 alkenyl or halogen,n represents 0 to 5,R.sup.1 and R.sup.2 each independently represents C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, C.sub.3-7 cycloalkyl which may optionally be substituted by C.sub.1-3 alkyl, epoxy-C.sub.3-5 alkan-1-yl, phenyl which may optionally be substituted, or aralkyl which may optionally be substituted, orR.sup.1 and R.sup.2 together with the N-atom to which they are attached, represent a cyclic ring which may be substituted, and some novel intermediates therefor.

Abstract: A composition and method for inhibiting corrosion by chlorine dioxide in oil field water flood systems are disclosed. The composition is comprised of an alcohol, an acid, a fatty imidazoline, an ethoxylated fatty diamine, and water. This composition has proven more effective than chromates at inhibiting the corrosion caused by chlorine dioxide, further without the serious toxicological effects caused by the use of chromates.

Abstract: A method and coating composition for producing protective coatings on metal surfaces of tubular goods, equipment and so forth used in processes associated with oxidative environments to inhibit corrosive effects of the oxidative environments thereon. The coating composition includes an aqueous liquid carrier and a corrosion inhibiting combination of a specific condensation product and an antimony compound. The antimony compound is activated by the condensation product and enhances the degree of protection achieved.

Abstract: In a first embodiment, the invention relates to the use of basic amine compounds of pronounced oleophilic character and at most limited solubility in water, which are capable of forming salts with carboxylic acids, as an additive for w/o invert drilling muds which contain in the continuous oil phase ester oils and, together with the disperse aqueous phase, emulsifiers, weighting agents, fluid loss additives and, if desired, other additives for protecting the drilling muds against unwanted thickening in use or for improving their flowability. In another embodiment, the invention relates to w/o invert drilling muds which are suitable for the improved offshore development of oil and gas sources and which are characterized by the presence of basic amine compounds of pronounced oleophilic character which are capable of forming salts with carboxylic acids.

Abstract: The present invention relates to an improved continuous phase for an oil based drilling fluid and specifically a synthetic hydrocarbon continuous phase which is non-polluting and minimally toxic. The invention provides excellent drilling fluid properties under a wide variety of drilling conditions. The synthetic hydrocarbons are selected from the group consisting of branched chain oligomers synthesized from one or more olefins containing a C.sub.2 to C.sub.14 chain length and wherein the oligomers have an average molecular weight of from 120 to 1000. In the drilling fluid compositions, suitable emulsifiers, wetting agents, viscosifiers, weight materials and fluid loss additives are utilized in conjunction with water and/or a brine phase for the desired rheological properties.

Abstract: The invention relates to the use of methylesters of C.sub.6-24 monocarboxylic acids as the oil phase or as part of the oil phase of invert drilling muds which are suitable for the environment-friendly development of oil and gas sources and which, in a continuous oil phase, contain a disperse aqueous phase together with emulsifirs, weighting agents, fluid loss additives and, if desired, other standard additives. In another embodiment, the invention relates to invert drilling muds which are particularly suitable for the environment-friendly development of oil and gas sources and which are characterized in that the oil phase contains methylesters of C.sub.6-24 monocarboxylic acids, if desired in admixture with other oil components from the class of non-polluting oils.

Abstract: A drilling fluid includes water, bentonite, a weighting agent, and an additive comprising a water-soluble polycondensate containing phosphorous and nitrogen such as phosphorylated-urea-formaldehyde or phosphorylated-melamine-formaldehyde. Such additives provide the desired rheological and filtration loss properties as well as thermal and shear stability. The additives are prepared by reacting phosphorous acid, urea and formaldehyde according to a Mannich-type reaction.

Abstract: This invention relates to a composition suitable for use in process for the removal of sulfides, especially hydrogen sulfide from a feed contaminated therewith. The composition comprises an aqueous solution of a chlorite and a corrosion inhibitor which is an amphoteric ammonium compound of the formula ##STR1## as herein defined. The inhibitor mitigates problems of corrosion associated with chlorite scavengers.