Abstract: The present invention provides microemulsion surfactant additives for use in aqueous well treating fluids to prevent the formation of stable emulsions and sludge when the aqueous treating fluids contact hydrocarbons. The additives are basically comprised of a solvent, a co-solvent, water, an aqueous liquid-hydrocarbon liquid de-emulsifying surfactant and a liquid hydrocarbon antisludging surfactant. Aqueous compositions including the additives and methods of treating subterranean formations or zones containing hydrocarbons using the compositions are also provided.

Abstract: The present invention relates to improved environmentally friendly solvent compositions for materials such as pipe dope, thread lubricants and the like and methods of utilizing such compositions. The nonaqueous solvent compositions are basically comprised of an emulsion of a surface active agent for breaking up and dispersing the materials, and D-limonene and a mixture of other terpenes including dipentene for dissolving the materials and glacial acetic acid.

Abstract: The present invention provides low viscosity acid-in-oil emulsions, surfactant systems and methods of using the emulsions and surfactants for stimulating the production of hydrocarbons from subterranean producing formations. The low viscosity acid-in-oil emulsions are basically comprised of a hydrocarbon oil forming the external phase of the emulsion, an emulsifying agent of a type which forms and stabilizes an acid-in-oil emulsion, an emulsion viscosity reducing agent comprising a fatty ammonium salt of a fatty acid and an aqueous acid solution forming the internal phase of the emulsion.

Abstract: The present invention provides low viscosity acid-in-oil emulsions, surfactant systems and methods of using the emulsions and surfactants for stimulating the production of hydrocarbons from subterranean producing formations. The low viscosity acid-in-oil emulsions are basically comprised of a hydrocarbon oil forming the external phase of the emulsion, an emulsifying agent of a type which forms and stabilizes an acid-in-oil emulsion, an emulsion viscosity reducing agent comprising a fatty ammonium salt of a fatty acid and an aqueous acid solution forming the internal phase of the emulsion.

Abstract: A concentrate which forms an acid internal microemulsion well treatment composition when added to an acid treatment fluid. The concentrate comprises in the range of from about 20% to about 98% by weight of a hydrocarbon carrier fluid, in the range of from about 1% to about 50% by weight of an alkyl alcohol having from 4 to 18 carbon atoms and in the range of from about 1% to about 50% by weight of an emulsifying agent comprising at least one compound selected from the group consisting of sulfate esters, phosphate esters, alkyl aromatic sulfonic acids, amine salts having ester or amide linkages, quaternary ammonium compounds having ester of amide linkages, propoxylated fatty acids, and propoxylated alcohols. Also disclosed are an acid internal microemulsion well treatment composition and a method of treating a subterranean formation to increase the production of hydrocarbons therefrom.

Abstract: A concentrate which forms an acid and/or water external microemulsion when added to a treatment fluid. The concentrate comprises an alkyl alcohol having in the range of from 4 to 18 carbon atoms, an emulsifying agent, a mutual solvent selected from the group consisting of glycol ethers and alkyoxylates of glycol ethers, and a co-solvent selected from the group consisting of polyethylene glycol, primary alcohols and alkyoxylates of alkyl alcohols. Also disclosed are an acid and/or water external microemulsion well treatment composition and a method of treating a subterranean formation to increase the production of hydrocarbons therefrom.

Abstract: An improved method and composition for reducing the production of sludge when contacting a subterranean formation containing oil which is subject to sludging with an aqueous acid solution. An anti-sludging agent such as a quaternary ammonium salt of a fatty amine, and one or more other additives are combined with the aqueous acid solution along with a dispersing agent which forms the aqueous acid solution and additives into a long-term homogeneous composition.

Abstract: An improved method and composition for reducing the production of sludge when contacting a subterranean formation containing oil which is subject to sludging with an aqueous acid solution. An anti-sludging agent and one or more other additives are combined with the aqueous acid solution along with a dispersing agent which forms the aqueous acid solution and additives into a long-term homogeneous composition.

Abstract: A method and composition for stimulating subterranean formations containing iron deposits. The composition comprises an admixture of (i) at least one member selected from the group consisting of hydroxylamine hydrochloride, hydroxylamine hydrobromide, hydroxylamine sulfate, hydrazine monohydrochloride, hydrazine dihydrochloride, hydrazine sulfate, hydrazine monobromide, hydrazine dibromide, hydrazine monoiodide, hydrazine diiodide and hydroquinone together with (ii) at least one member selected from the group consisting of gluconodeltalactone, citric acid, salts of citric acid, ethylenediaminetetraacetic acid, salts of ethylenediamianetetraacetic acid, nitrilotriacetic acid, salts of nitrilotriacetic acid, hydroxyethylethylenediaminetriacetic acid, and salts of hydroxyethylethylenediaminetriacetic acid and (iii) a catalytic amount of a solubilized salt of a compound capable of providing cupric, cuprous, nickel, zinc ions or mixtures thereof.

Abstract: A method and composition for stimulating subterranean formations containing iron deposits. The composition comprises a compound comprising at least one member selected from the group consisting of dihydroxymaleic acid, salts of dihydroxymaleic acid and gluconodeltalactone. The method comprises contacting the subterranean formation in an appropriate manner with the above-described composition present in an amount sufficient to sequester iron.

Abstract: Asphaltenic and paraffinic containing deposits are removed by contacting the deposits with an aqueous dispersion of a hydrocarbon solvent, an amine and a nonionic alkylated aryl polyether alcohol.