Abstract: A powder composition comprising viscoelastic surfactant forms, in aqueous solution, a viscoelastic wellbore treatment fluid.

Abstract: A method of creating a carbon dioxide hydrate is disclosed. The preferred steps include supplying liquid carbon dioxide and a dissociation agent to a hydrocarbon hydrate, decomposing the hydrocarbon hydrate by the dissociation agent into a hydrocarbon gas and liquid water, and forming the carbon dioxide hydrate from the liquid carbon dioxide and the liquid water. The dissociation agent preferably is at least one of an inorganic salt, a surface active agent, a hydrate inhibitor, and an absorption solution. Furthermore, a substance composition of liquid carbon dioxide and the dissociation agent is described, which is provided for depositing carbon dioxide hydrate in a subterranean geological formation. Furthermore, a deposition device is described, which is configured for depositing carbon dioxide hydrate in a subterranean geological formation.

Abstract: The present invention relates to acidic treatment fluids that comprise an acid fluid and an ester-containing quaternary ammonium compound (“esterquat”) and methods of their use. One embodiment of the present invention provides a method of inhibiting metal corrosion during a subterranean treatment operation comprising using an acidic treatment fluid comprising an acidic fluid and an esterquat. Another embodiment of the present invention provides a method of reducing sludge formation during a subterranean treatment operation formation comprising the step of using an acidic treatment fluid comprising an acidic fluid and an esterquat. Another embodiment of the present invention provides a method of inhibiting the formation of emulsions during a subterranean treatment operation comprising using an acidic treatment fluid comprising an acidic fluid and an esterquat. Another embodiment of the present invention provides an acidic subterranean treatment fluid comprising an acidic fluid and an esterquat.

Abstract: Methods are provided for treating a portion of a well and include the steps of: (a) forming a treatment fluid comprising an aqueous solution, wherein the aqueous solution comprises: (i) water; (ii) a water-soluble polysaccharide; (iii) one or more water-soluble salts, wherein the one or more salts are selected and are in at least a sufficient concentration such that the water-salt solution has a density of at least 10 ppg; and (iv) urea; and (b) introducing the treatment fluid into the portion of the well. According to the inventions, the concentration of the urea in the water is in at least a sufficient concentration such that aqueous solution: (1) has a G? of at least 2 Pa, or (2) is filterable. According to the inventions, an identical aqueous solution except with less than the sufficient concentration of the urea would not satisfy the above conditions.

Abstract: Piezoelectric crystal particles (which include pyroelectric crystal particles) enhance the viscosity of aqueous fluids that have increased viscosity due to the presence of viscoelastic surfactants (VESs). In one non-limiting theory, when the fluid containing the viscosity enhancers is heated and/or placed under pressure, the particles develop surface charges that associate, link, connect, or relate the VES micelles thereby increasing the viscosity of the fluid. The higher fluid viscosity is beneficial to crack the formation rock during a fracturing operation, reduce fluid leakoff, and carry high loading proppants to maintain the high conductivity of fractures.

Abstract: The invention discloses method of treatment and reuse of oilfield produced water. The method comprises: providing an aqueous medium comprised at least in part of oilfield produced water; contacting the aqueous medium with a zirconium compound; whereby the fluid viscosity and/or fluid drag reduction ability of the combination of the aqueous medium and zirconium compound is improved compared to the aqueous medium alone; introducing the combination in to the well; and allowing the combination to contact the formation. In another embodiment, the aqueous medium is further contacted by a friction-reduction additive. Still in another embodiment, the aqueous medium is further contacted by a gelling additive. Still in another embodiment, the fluid is energized with a gas.

Abstract: Disclosed are methods of treating subterranean formations with rapidly hydratable treatment fluids based upon heteropolysaccharides. In particular, the invention relates to treatment methods with fluids containing a heteropolysaccharide, aqueous medium, and an electrolyte, wherein the fluids may further include a gas component, a surfactant and/or an organoamino compound. The fluids exhibit good rheological properties at elevated temperatures, and unusually rapid hydration rates which allows utilizing such fluids without the need of hydration tanks.

Abstract: The present invention relates to the use of an oil formulation in the field of the oil industry, in particular for the prevention of water penetration. The formulation according to the invention is in particular intended to be injected into underground formations, such as injection wells or production wells.

Abstract: Treatments fluids relating to the hydrolysis of water-hydrolysable materials are provided. In one embodiment, provided is a treatment fluid that comprises an aqueous liquid, a water-miscible solvent, and a water-hydrolysable material. Also provided is a hydrolysis retarder composition that comprises an aqueous liquid and a water-miscible solvent.

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: An oilfield treatment method is given that uses fluids that contain surfactants used as foamers and/or viscosifiers such that the fluids pass the Alberta Energy and Utilities Board Directive 27 requirements for low toxicity to certain bioluminescent bacteria. Such fluids may be used in oilfield treatments, for example drilling and stimulation, near fresh water aquifers. The surfactants are certain non-ionic surfactants that are not aromatic, or certain amphoteric surfactants (that can be neutral), or certain zwitterionic surfactants, (in which both positive and negative charges are present in a single molecule so that the whole molecule is neutral).

Abstract: The present invention provides a method of forming a viscosified treatment fluid comprising: providing a treatment fluid that comprises water and a gelling agent; contacting the treatment fluid with a boronic acid crosslinking agent so as to form a crosslinked gelling agent, wherein the boronic acid crosslinking agent comprises a compound having the formula: The present invention also provides methods of crosslinking gelling agent molecules, methods of treating a subterranean formation, methods of reusing viscosified treatment fluids, methods of fracturing subterranean formations, and methods of placing a gravel pack in subterranean formations. The present invention also provides boronic acid crosslinking agents and viscosified treatment fluids that comprise crosslinked gelling agents, the crosslinked gelling agent being formed from a reaction comprising a gelling agent and a boronic acid crosslinking agent.

Abstract: The present invention relates to well bore stabilization and, more particularly, to treatment fluids that may reduce the tendency of shales to swell and associated methods. In some embodiments, the present invention provides a method of stabilizing a subterranean formation that comprises a shale, the method comprising contacting the subterranean formation that comprises the shale with a treatment fluid, the treatment fluid comprising a base fluid, and a hydrophobically modified polymer. In other embodiments, the treatment fluids comprise a base fluid and a hydrophilically modified polymer. In yet other embodiments, the present invention provides shale-inhibiting components, treatment fluids, and methods of reducing the tendency of shale to swell when exposed to a treatment fluid.

Abstract: A water-based wellbore treatment fluid contains: one or more viscoelastic-gelling carboxylic acids and/or alkali metal salts thereof; and one or more solubilising alkylolamines. The carboxylic acids and/or alkali metal salts and the alkylolamines are present in the fluid in respective amounts such that, at 25° C., the alkylolamines solubilise a sufficient portion of the carboxylic acids and/or alkali metal salts to render the fluid viscoelastic. A remaining portion of the carboxylic acids and/or alkali metal salts forms a suspension of solid particulates in the fluid.

Abstract: Methods and compositions of treating formations using viscoelastic treatment fluids are provided that reduce the amount of fluid loss to the formations due to the lack of polymer backbone in the viscoelastic treatment fluids. The methods and compositions of treating formations include a fluid loss additive that includes a copolymer that includes a hydrophilic monomeric unit and a first anchoring monomeric unit.

Abstract: A process for preparing a stable zirconium triethanolamine cross-linking agent comprises contacting a solution of a zirconium triethanolamine complex with water at a temperature of 50° C. to 90° C. at a mole ratio of triethanolamine:zirconium in the range of 3.5:5.5 and at a mole ratio of water:zirconium in the range of 20:1 to 1:1. The stable zirconium triethanolamine complex can be used in a cross-linking composition. Further disclosed are methods to use the composition in oil field applications for hydraulic fracturing and plugging of permeable zones and leaks in subterranean formations.

Abstract: A cross-linking composition comprises (a) an aqueous liquid, (b) a pH buffer, (c) a cross-linkable organic polymer, (d) a cross-linking agent which comprises an organic titanate, an organic zirconate, or combinations thereof, and (e) a delay agent which is a hydroxyalkylaminocarboxylic acid. The composition provides flexibility in rate of cross-linking and can be used over a wide range of pH. Further disclosed are methods to use the composition in oil field applications for hydraulic fracturing and plugging of permeable zones and leaks in subterranean formations.

Abstract: Viscoelastic surfactant (VES) gelled aqueous fluids containing water, a VES, an internal breaker, a VES stabilizer, a fluid loss control agent and a viscosity enhancer are useful as treating fluids and particularly as fracturing fluids for subterranean formations. These VES-based fluids have faster and more complete clean-up than polymer-based fracturing fluids. The use of an internal breaker permits ready removal of the unique VES micelle based pseudo-filter cake with several advantages including reducing the typical VES loading and total fluid volume since more VES fluid stays within the fracture, generating a more optimum fracture geometry for enhanced reservoir productivity, and treating reservoirs with permeability above the present VES limit of approximately 400 md to at least 2000 md.

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: Methods and compositions are provided that inhibit the corrosion of metal surfaces by aqueous acid solutions. The inhibition is basically achieved by the addition of a reaction product of an alpha,beta-unsaturated aldehyde or ketone with a primary or secondary amine to the aqueous acid solution.

Abstract: A composition comprising: (i) a chelating aminocarboxylic acid-C8-C22 amine complex; (ii) a C15-C21 bis(2-hydroxyethyl)amide; and (iii) a C15-C44 imidazoline compound.

Abstract: Methods and compositions useful in treating subterranean formations, and more particularly, breaker compositions that may be useful in treating subterranean formations wherein synthetic polymers are used, are provided. Of the many methods and compositions provided herein, one composition comprises a source of hydrogen peroxide and an activator. One method comprises providing a polymer breaker composition comprising a source of hydrogen peroxide and an activator; introducing the polymer breaker composition into a well bore which penetrates a subterranean formation; allowing the activator to activate the source of hydrogen peroxide to create an oxidizing species; and allowing the oxidizing species to break synthetic polymers present in the subterranean formation.

Abstract: Embodiments of the Present Invention relate to a reversibly thickenable non-polymeric fluid that has low viscosity in strong acid, gels when the acid concentration is reduced by only a small amount, and is subsequently decomposed by the acid. In particular it relates to an aqueous mixture of zwitterionic surfactants, inorganic acids, and organic acids Most particularly it relates to the use of this fluid as a diverting agent for easily-damaged sandstones, for example prior to matrix acidizing.

Abstract: A fluid for use in a subterranean formation penetrated by a wellbore, the fluid comprising: (a) water; (b) an orthoester; and (c) a surfactant comprising a tertiary alkyl amine ethoxylate generally represented by the following formula: (CH2—CH2—O)XH R—N< (CH2—CH2—O)YH wherein R is an alkyl group or aryl group, and wherein X and Y are each independently at least one. A method of fracturing a subterranean formation, comprising the step of forming a foamed fracturing fluid comprising water; an orthoester; a surfactant comprising a tertiary alkyl amine ethoxylate generally represented by the formula above; and a gas. The method also provides the step of introducing the foamed fracturing fluid into a subterranean formation at a pressure sufficient to create a fracture in the subterranean formation.

Abstract: The invention relates to a method to repair a leak in a geological structure or a construction comprising a geological material, comprising administering a liquid nutrient composition, comprising an energy source for anaerobic bacteria and a multivalent metal ion upstream of the leak allowing micro-organisms present in the structure or construction to ferment the energy source and to grow, thereby increasing biomass in and/or around the leak releasing mineral particles upstream of the leak allowing the mineral particles to migrate to the leak; and allowing the mineral particles to settle in the biomass.

Abstract: The invention relates to a composition for producing foams, in particular for mineral oil and natural gas production.

Abstract: Compositions and methods are given for delayed breaking of viscoelastic surfactant gels inside formation pores, particularly for use in hydraulic fracturing. Breaking inside formation pores is accomplished without mechanical intervention or use of a second fluid. Acidic internal breakers such as sulfuric acid and nitric acid are used. The break may be accelerated, for example with a free radical propagating species, or retarded, for example with an oxygen scavenger.

Abstract: In a method for optimizing gas lift operations in the production of crude oil, a surfactant is injected with the lift gas into the an oil well such that the surface tension between the lift gas and the formation fluid being produced is reduced and/or a lift gas-formation fluid foam is formed. The reduction in surface tension and/or foam formation increases the efficiency of the lift gas for lifting the formation fluid to the surface. The surfactant is selected to minimize corrosion. The surfactants consist essentially of sultaines, hydroxy sultaines, and their salts. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: The present invention provides aqueous viscoelastic compositions comprising a cleavable anionic surfactant which is a sulphonate and possibly also an electrolyte. The cleavable surfactants useful in the present invention comprise a 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 viscoelastic composition are usually altered upon cleavage of the cleavable surfactant generally resulting in the elimination of the viscosifying, 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.

Abstract: A synergistic blend for foaming concentrated brines comprises at least one foaming agent (in an amount between from about 10 to about 90 weight percent of the blend) and a compound of the formula: CnH2n+1—N—[(CH2)mCOOM]2??(I) wherein n is 4 to 11, M is an alkali metal and m is 1 to 3. Especially suitable as foaming agent are quaternary ammonium salts, alkyl betaines, alkylamidopropyl betaines, sulfabetaines, hydroxysultaines, amphoteric perfluorohydrocarbons, as well as alkylether sulfates. Such synergistic blends are especially useful in the foaming of saturated or near saturated brines.

Abstract: A well treatment microemulsion for use in a subterranean formation is disclosed, the microemulsion comprises a solvent blend comprising a solvent and a co-solvent; a surfactant blend comprising a surfactant, wherein the surfactant blend is able to give formation intermediate wettability properties; an alcohol; and a carrier fluid; wherein the alcohol, the solvent and surfactant blends are combined with the carrier fluid to produce the well treatment microemulsion. By intermediate wettability it is meant that the water has an advancing contact angle on the surface between 62 and 133 degrees. The associate method of treating a subterranean formation of a well with the microemulsion and the associate method of modifying the wettability of the formation with the microemulsion are also disclosed.

Abstract: Fluids viscosified with viscoelastic surfactants (VESs) may have their fluid loss properties improved with at least one mineral oil which has a viscosity greater than 20 cps at ambient temperature. The mineral oil may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. In one non-limiting embodiment, the mineral oil is added to the fluid after it has been substantially gelled in an amount between about 0.2 to about 10% by volume.

Abstract: The invention discloses a method of for changing the water permeability of a subterranean formation of a well, the method comprising: providing a fluid comprising a liquid carrier and a viscoelastic surfactant; introducing the fluid into the well; and contacting the fluid and the subterranean formation wherein the action of the liquid carrier and the viscoelastic surfactant is able to change the water permeability of the subterranean formation. The fluid may further comprise methanol, or a salt which can be embodied within the carrier fluid. Advantageously, no further RPM polymer is used. In a first aspect the method is used for reducing the amount of water produced, in as second aspect for improving the oil recovery.

Abstract: This invention provides compositions comprising an aqueous well fluid and at least one nonionic acetylenic alcoholic surfactant. The compositions may further comprise at least one fluoroaliphatic surfactant. Methods for recovery of aqueous well fluids involving the use of at least one nonionic acetylenic alcoholic surfactant are also provided, and these methods may further comprise the use of at least one fluoroaliphatic surfactant.

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: A cross-linking composition comprising (a) an aqueous liquid; (b) a pH buffer; (c) a cross-linkable organic polymer; and (d) a solution of a zirconium cross-linking agent comprising the product of contacting a zirconium complex with an alkanolamine and ethylene glycol wherein the mole ratio of alkanolamine to zirconium is 2:1 to 4:1 and the mole ratio of ethylene glycol to zirconium is 1:1 to 10:1. Optionally, water, hydroxyalkylated ethylenediamine, or both are added to the zirconium complex. The cross-linking composition of this invention is useful in oil field applications, for example, for hydraulically fracturing a subterranean formation and for plugging permeable zones or leaks in a subterranean formation.

Abstract: A method is described for treating a subterranean formation with a low viscosity fluid system that contains a viscoelastic surfactant at a concentration too low to viscosify the fluid, but that is concentrated in the formation so that the fluid system gels. The fluid also contains a formation-dissolving agent. The fluid is used in acidizing, acid fracturing, and diversion.

Abstract: In a method of treating a sandstone-containing formation penetrated by a wellbore, a treatment fluid comprising an aqueous fluid containing a Bronsted acid, a hydrogen fluoride source and an organic acid or salt thereof that is substantially soluble in the aqueous fluid is formed. The treatment fluid contains less than about 2% of fluoride (F?) by weight of the fluid and from 2% or less of sodium (Na+) by weight of the fluid. The treatment fluid is introduced into the formation through the wellbore as a single-stage without introducing an acid-containing fluid preflush into the formation prior to introducing the treatment fluid.

Abstract: An under-balanced drilling fluid additive is disclosed which reduces reactive shale and/or clay swelling during under-balanced drilling operations, where the additive includes an effective amount of a choline salt. A method for under-balanced drilling is also disclosed including the step of circulating a drilling fluid including an effective amount of a choline salt to reduce reactive shale and/or clay swelling during under-balanced drilling operations.

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: Alkaline earth metal compounds may be fluid loss control agents for viscoelastic surfactant (VES) fluids used for well completion or stimulation in hydrocarbon recovery operations. The VES fluid may further include proppant or gravel, if it is intended for use as a fracturing fluid or a gravel packing fluid, although such uses do not require that the fluid contain proppant or gravel. The fluid loss control agents may include, but not be limited to, oxides and hydroxides of alkaline earth metal, and in one case magnesium oxide where the particle size of the magnesium oxide is between 1 nanometer to 0.4 millimeter. The fluid loss agent appears to associate with the VES micelles and together form a novel pseudo-filter cake crosslinked-like viscous fluid layer that limits further VES fluid flow into the porous media. The fluid loss control agent solid particles may be added along with VES fluids.

Abstract: Embodiments of the present invention are directed to defoaming methods and compositions for well treatment fluids. An exemplary embodiment of the present invention provides a method of defoaming a well treatment fluid, comprising combining a defoaming composition with the well treatment fluid, wherein the defoaming composition comprises an amide of a carboxylic acid, a polypropylene glycol, an ethoxylated and propoxylated fatty alcohol, an ethoxylated alcohol comprising from 3 carbons to 6 carbons, and a hydrophobic silica in an amount of up to about 3% by weight of the defoaming composition.

Abstract: Piezoelectric crystal particles (which include pyroelectric crystal particles) enhance the viscosity of aqueous fluids that have increased viscosity due to the presence of viscoelastic surfactants (VESs). In one non-limiting theory, when the fluid containing the viscosity enhancers is heated and/or placed under pressure, the particles develop surface charges that associate, link, connect, or relate the VES micelles thereby increasing the viscosity of the fluid. The higher fluid viscosity is beneficial to crack the formation rock during a fracturing operation, reduce fluid leakoff, and carry high loading proppants to maintain the high conductivity of fractures.

Abstract: Methods and compositions for wellbore treating fluids that include zeolite and at least one carrier fluid.

Abstract: A solid zirconium cross-linking agent is prepared comprising zirconium and hydroxyalkylated ethylene diamine ligand. Use of the cross-linking agent in compositions for oil field applications such as hydraulic fracturing and plugging of permeable zones is also disclosed.

Abstract: The present invention relates to novel aqueous wellbore treatment fluids containing a gas component, a heteropolysaccharide, an electrolyte, and a surfactant, wherein the fluids may further include an organoamino compound. The fluids exhibit good rheological properties at elevated temperatures. Methods of using fluids containing at least an aqueous medium, a gas component, a heteropolysaccharide and a surfactant for hydraulically fracturing, well cleanup and gravel packing operations, are also disclosed.

Abstract: A method of fracturing a subterranean formation, the method including injecting a fracturing fluid into the well, wherein said fracturing fluid includes: an oleaginous fluid; and an amine surfactant having the structure wherein R is a C12-C22 aliphatic hydrocarbon; R? is an independently selectable from hydrogen or C1 to C3 alkyl; A is NH or O, and 1?x+y?3; and oil-wet proppant material. Additionally, the method includes pressurizing the fluid so as to cause the subterranean formation to fracture and allow the proppant materials to enter the crack, adding acid to the fluid so as to change the oil-wet proppant materials into water-wet proppant materials, and washing the well with an aqueous based wash solution.

Abstract: Corrosive effects arising during oilfield treatment applications are inhibited and/or prevented by introducing into an oil or gas well at least one compound of formula I: wherein: R1 is independently H, —[—CnH2nO—]a—H, or an alkyl group having from 1 to about 24 carbon atoms; R2 is independently H or —[—CnH2nO—]b—H, R3 is independently —[—CH2]c—, or —CdH2d—[—OCnH2n—]e—, R4 is independently H or —[—CnH2nO—]f—H, R5 is independently H or —[—CnH2nO—]g—H, a is from about 1 to about 8; b+f+g is between 0 to about 30; c is from about 1 to 6; d is from about 1 to 6; e is from about 1 to about 8; and n is 2 or 3. Such corrosive effects are especially inhibited in the treatment of sour wells where H2S corrosion is a potential problem as well as conduits used during the treatment of subterranean formations.

Abstract: Embodiments of the present invention are directed to defoaming methods and compositions for well treatment fluids. An exemplary embodiment of the present invention provides a method of defoaming a well treatment fluid, comprising combining a defoaming composition with the well treatment fluid, wherein the defoaming composition comprises an amide of a carboxylic acid, a polypropylene glycol, an ethoxylated and propoxylated fatty alcohol, an ethoxylated alcohol comprising from 3 carbons to 6 carbons, and a hydrophobic silica in an amount of up to about 3% by weight of the defoaming composition.