Emulsions, treatment fluids and methods for treating subterranean formations are provided, wherein the emulsions comprise water, a water-immiscible liquid, one or more polymers, and an inverting surfactant composition comprising one or more surfactants selected from the group consisting of ethoxylated alcohol compounds, ethoxylated fatty acid compounds, and alkyl polyethyleneglycol ether carboxylic acid compounds, and salts or esters thereof. The emulsions are particularly suitable for use in brine.

Emulsions, treatment fluids and methods for treating subterranean formations are provided, wherein the emulsions comprise water, a water-immiscible liquid, one or more polymers, and an inverting surfactant composition comprising one or more surfactants selected from the group consisting of ethoxylated alcohol compounds, ethoxylated fatty acid compounds, and alkyl polyethyleneglycol ether carboxylic acid compounds, and salts or esters thereof. The emulsions are particularly suitable for use in brine.

Provided is an invert emulsion oil-based drilling fluid composition that may include an invert emulsion of an oil phase and an aqueous phase. The oil phase may include an oleaginous fluid. The composition may include a low-end rheology modifier that is a C-36 dimer diamine dihydrochloride salt. Further provided is a method that may include introducing the invert emulsion oil-based drilling fluid composition into a wellbore.

Provided is an invert emulsion oil-based drilling fluid composition that may include an invert emulsion of an oil phase and an aqueous phase. The oil phase may include an oleaginous fluid. The composition may include a low-end rheology modifier that is a C-36 dimer diamine dihydrochloride salt. Further provided is a method that may include introducing the invert emulsion oil-based drilling fluid composition into a wellbore.

An additive composition includes a rheology modifier selected from alcohol ethoxylates, amine ethoxylates, or ethylene oxide/propylene oxide copolymers, wherein the rheology modifier has an HLB ranging from about 4 to 10; and a winterizing agent that is at least one aliphatic non-ionic surfactant that has a branched structure and/or includes at least one unsaturation, wherein the winterizing agent has an HLB value between about 8 and 10.5.

An additive composition includes a rheology modifier selected from alcohol ethoxylates, amine ethoxylates, or ethylene oxide/propylene oxide copolymers, wherein the rheology modifier has an HLB ranging from about 4 to 10; and a winterizing agent that is at least one aliphatic non-ionic surfactant that has a branched structure and/or includes at least one unsaturation, wherein the winterizing agent has an HLB value between about 8 and 10.5.

A method of reducing a density of a density of a stable emulsion drilling fluid may comprise providing a stable emulsion drilling fluid comprising: an aqueous liquid; a biopolymer; an emulsifier; solid particulates; and an oil; wherein the stable emulsion drilling fluid is capable of remaining in quiescent storage at approximately 70° F. and atmospheric pressure without phase separation for about 8 hours or longer; circulating the stable emulsion drilling fluid though a drill string and annulus; adding additional oil to the stable emulsion drilling fluid to decrease the density of the stable emulsion drilling fluid and produce a reduced density stable emulsion drilling fluid; and circulating the reduced density stable emulsion drilling fluid though the drill string and the annulus.

Well treatment fluids may include solid particles comprising one or more components selected from the group consisting of urea, ammonium nitrate, ammonium chloride, barium hydroxide, and ammonium thiocyanate. These well treatment fluids may also include a carrier fluid, which may be an aqueous polymeric fluid, an oil, or combinations thereof. The aqueous polymeric fluid may include a polymer selected from the group consisting of guar gum, hydroxypropyl guar, carboxymethyl hydroxypropyl guar, cellulose, or polyacrylamide. The oil may include a material selected from the group consisting of diesel, mineral oil, and wax. Methods for reducing an acid carbonate reaction in a carbonate formation may include pumping a composition of solid particles into a formation; releasing the solid particles from the capsules or emulsion within the formation; and injecting an acid following the releasing step or during pumping, wherein the acid carbonate reaction is carried out at a reduced reaction rate.

Well treatment fluids may include solid particles comprising one or more components selected from the group consisting of urea, ammonium nitrate, ammonium chloride, barium hydroxide, and ammonium thiocyanate. These well treatment fluids may also include a carrier fluid, which may be an aqueous polymeric fluid, an oil, or combinations thereof. The aqueous polymeric fluid may include a polymer selected from the group consisting of guar gum, hydroxypropyl guar, carboxymethyl hydroxypropyl guar, cellulose, or polyacrylamide. The oil may include a material selected from the group consisting of diesel, mineral oil, and wax. Methods for reducing an acid carbonate reaction in a carbonate formation may include pumping a composition of solid particles into a formation; releasing the solid particles from the capsules or emulsion within the formation; and injecting an acid following the releasing step or during pumping, wherein the acid carbonate reaction is carried out at a reduced reaction rate.

Injection fluids formed of reverse emulsions and related methods of forming and using reverse emulsions for cavity control in solution mining. The reverse emulsion can reduce the volume of oil required to create an oil pad at the roof of a solution mining cavern in order to prevent vertical leaching and cavern collapse. The reverse emulsion can be formed from an emulsifier, a brine solution and oil. The emulsifier concentration can range from about 1% to about 5% by weight of the reverse emulsion. The emulsifier and the oil can be combined to form an oil/emulsifier mixture, wherein the oil/emulsifier mixture is combined with the brine solution to form the reverse emulsion. The oil/emulsifier mixture can be from about 1% to about 5% by weight of the reverse emulsion.