Abstract: A method for oil recovery whereby an exothermic water reactant (EWR) encapsulated in a water soluble coating is placed in water and pumped into one or more oil wells in contact with an oil bearing formation. After the water carries the EWR to the bottom of the injection well, the water soluble coating dissolves and the EWR reacts with the water to produce heat, an alkali solution, and hydrogen. The heat from the EWR reaction generates steam, which is forced into the oil bearing formation where it condenses and transfers heat to the oil, elevating its temperature and decreasing the viscosity of the oil. The aqueous alkali solution mixes with the oil in the oil bearing formation and forms a surfactant that reduces the interfacial tension between the oil and water. The hydrogen may be used to react with the oil at these elevated temperatures to form lighter molecules, thus upgrading to a certain extent the oil in situ.

Abstract: A fracturing fluid for a downhole environment is disclosed, comprising a water-sensitive gel; and a hydrated breaker. A fracturing fluid for a downhole environment is also disclosed, the fracturing fluid comprising a water-sensitive carrier and a breaker, the breaker comprising one or more hydrates, and wherein water of the one or more hydrates is releasable so as to act with the water-sensitive carrier to reduce the viscosity of the fluid. A method of treating a downhole environment with a fracturing fluid is also disclosed, the method comprising: providing to the downhole environment a fluid comprising a water-sensitive carrier and a breaker, the breaker comprising one or more hydrates; and allowing water from the one or more hydrates to release so as to act with the carrier to reduce the viscosity of the fluid.

Abstract: For lost circulation treatment, a lost circulation additive including a dry mixture of water soluble crosslinkable polymer, a crosslinking agent, and a reinforcing material of fibers and/or comminuted plant materials. The method of forming a lost circulation fluid includes contacting the additive with water or an aqueous solution, with a method of conforming the formation further including the step of injecting the fluid into the wellbore.

Abstract: Viscoelastic compositions are disclosed herein containing an effective amount of one or more random or structurally defined polycationic quaternary ammonium compounds for controlling the viscoelasticity of the composition. In at least one aspect, the present technology provides polycationic quaternary ammonium compounds comprising bis-quaternary compounds. In another aspect, the present technology provides viscoelastic compositions that comprise polycationic quaternary ammonium compounds comprising bis-quaternary compounds. Preferred viscoelastic compositions of the present technology maintain viscoelasticity at a temperature greater than about 80° C., preferably greater than about 100° C. or about 110° C. when the amount of the one or polycationic quaternary compounds is less than about 10% by weight based on the total weight of the composition.

Abstract: Viscoelastic compositions are disclosed herein containing an effective amount of one or more random or structurally defined polycationic quaternary ammonium compounds for controlling the viscoelasticity of the composition. In one aspect, the present technology provides polycationic quaternary ammonium compounds that comprise bis-quaternary compound. The bis-quaternary compounds of the present technology can be symmetric or dissymmetric. In another aspect, the present technology provides viscoelastic well bore treatment fluids comprising water, and at least one polycationic quaternary ammonium compound that comprises a bis-quaternary compound. In another aspect, the present technology provides polycationic carboxylates. Preferred viscoelastic compositions of the present technology maintain viscoelasticity at a temperature greater than about 80° C., preferably greater than about 100° C. or 110° C.

Abstract: Viscoelastic surfactant (VES) based fluid systems for zone isolation and flow control are effective in water and/or gas shutoff applications. The fluid systems may include brine, a viscosity enhancer, as well as the VES, and optionally a stabilizer for high temperature applications. The stabilizer may be an alkali earth metal oxide, alkali earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, Al2O3, and mixtures thereof. The viscosity enhancer may include pyroelectric particles, piezoelectric particles, and mixtures thereof. The fluid system is easy to pump into the formation, and after pumping, the fluid system will generate very high viscosities to prevent the VES fluid from flowing back to stop undesirable water and/or gas production.

Abstract: The present invention is directed to novel additives packages, to fluid compositions including the additives, to methods of using the fluid compositions and the additives package, to methods of recovering hydrocarbons, and to petroleum products made from hydrocarbons derived from these methods. The novel additives packages may be used in a fluid composition for fracturing a subterranean. The additives package of the present invention include one or more gelling agents; one or more cross-linking agent; and one or more high temperature stabilizers; wherein the additives package further comprises one or more ingredients selected from the group consisting of a clay stabilizer, a metallic base, a cross-link retarder, and a gel breaker, and any combination thereof; and wherein the additives package optionally includes a diluent.

Abstract: An oilfield servicing fluid composition containing an aldehyde guar produced by enzymatic oxidation of a non-derivatized, straight guar or of a guar derivative. The enzyme used to oxidize the guar to the aldehyde guar is galactose oxidase, which may be combined with catalase or catalase and peroxidase. The aldehyde guar is useful as an effective gelling agent for oilfield servicing fluids such as hydraulic fracturing fluids and stimulation fluids.

Abstract: A method of servicing a wellbore comprising preparing a composition comprising a calcium aluminate cement, water, a polyphosphate, a pozzolan, and a set retarding agent, wherein the set retarding agent comprises an alkali halide and a basic phosphate salt, placing the composition in the wellbore and allowing the composition to set. A composition comprising a calcium aluminate cement in an amount of from about 30 wt. % to about 60 wt. % and a set retarding agent in an amount of from about 0.1 wt. % to about 15 wt. % based upon the total weight of the composition, wherein the set retarding agent comprises an alkali halide and a basic phosphate salt in a ratio of from about 3:1 to about 1:3.

Abstract: Methods for treating wellbores using fluids containing a sphingan heteropolysaccharide which contributes viscosity stability and a decrease in friction pressure. Some methods are clean-out operations using recyclable-viscosity fluids containing at least a sphingan heteropolysaccharide and an optional salt. Others include methods of pumping fluids incorporating sphingan heteropolysaccharides to reduce pumping frictional pressure.

Abstract: Viscoelastic compositions are disclosed herein containing an effective amount of one or more random or structurally defined polycationic quaternary ammonium compounds for controlling the viscoelasticity of the composition. In at least one aspect, the present technology provides polycationic quaternary ammonium compounds comprising dissymmetric bis-quaternary compounds. In another aspect, the present technology provides viscoelastic compositions comprising polycationic quaternary ammonium compounds that comprise dissymmetric bis-quaternary compounds. In yet another aspect, the present technology provides polycationic quaternary ammonium compounds comprising a carboxylate functional polycationic quaternary ammonium compound. Preferred viscoelastic compositions of the present technology maintain viscoelasticity at a temperature greater than about 80° C., preferably greater than about 100° C. or about 110° C.

Abstract: A method of treating a medium for water fracturing is disclosed, the method comprises: introducing at least one biocide and at least one metabolic inhibitor in the medium, using the medium for water fracturing. In another aspect a method of controlling the post-fracture reservoir souring by the metabolic activities of sulfate reducing bacteria of a well is described: at least one biocide and at least one metabolic inhibitor are introduced in a medium made of water, the medium is used for fracturing the well, and the medium remains in the reservoir to kill and/or inhibit growth of sulfate reducing bacteria.

Abstract: Methods and compositions useful in acidizing a subterranean formation with an oil-in-water emulsion that includes a sulfonate ester, a fluoride salt, a proppant, and water. The reaction of the ester and fluoride salt is delayed so that hydrofluoric acid is produced in-situ.

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: Methods of servicing a wellbore include generating gas in a plugging composition in situ within a permeable zone in the wellbore, thereby improving the ability of the plugging composition to seal the permeable zone. The gas may be generated via a chemical reaction by, for example, introducing first and second reactants to the plugging composition that can react at ambient temperatures in the wellbore. In an embodiment, the first and second reactants are concurrently pumped into the wellbore via separate flow paths within two concentric conduits to the permeable zone where they are allowed to contact each other in the presence of the plugging composition. In another embodiment, the first reactant, the second reactant, and a retarder for slowing the reaction between the two reactants are concurrently pumped to the permeable zone. In yet another embodiment, one of the reactants is encapsulated to delay a reaction between the two reactants.

Abstract: The invention relates to surfactant based viscoelastic fluids for enhancing the productivity of a hydrocarbon-bearing formations, such as oil wells. The viscoelastic fluids of the invention have particular applicability in acid fracturing of subterranean formations surrounding oil and gas wells. The viscoelastic fluid contains an inorganic acid and at least one C10 to C24 alkyl trialkyl quaternary ammonium aromatic salt such as quaternary ammonium salicylate or phthalate. An anionic surfactant may also be present in the viscoelastic fluid. The addition of the C10 to C24 alkyl trialkyl quaternary ammonium aromatic salt to the inorganic acid causes gellation of the acid.

Abstract: Water flood materials may contain an effective amount of a nano-sized particulate additive to inhibit or control the movement of fines within a subterranean formation during a water flood secondary recovery operation. The particulate additive may be an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, transition metal oxide, transition metal hydroxide, post-transition metal oxide, post-transition metal hydroxide, piezoelectric crystal, and/or pyroelectric crystal. The particle size of the magnesium oxide or other agent may be nanometer scale, which scale may provide unique particle charges that help control and stabilize the fines, e.g. clays.

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: A completion and workover fluid composition comprising, water and at least one rheology modifier and/or fluid loss control agent, and at least one other ingredient selected from the group consisting of inorganic salts, shale inhibitors, corrosion inhibitor, biocide, defoamers and finely divided solids particles (e.g., bentonite, attapulgite, sepiolite, calcium carbonate, etc.), depending upon the desired attributes, wherein the rheology modifier and/or the fluid loss control agent is an ethoxylated raw cotton linters or a modified ethoxylated raw cotton linters. The ethoxylated raw cotton linters provides comparable or better rheology and viscosity properties compared to high molecular weight commercial HECs made from purified cotton linters. These ethoxylated raw cotton linters derivatives are suitable for applications in oil-well servicing fluids, particularly to enhance functional properties of completion and workover fluids used during oil-well drilling operations.

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

Abstract: The current invention provides a novel downhole maleic acid solution suitable for restoring fluid permeability to subterranean formations that were previously treated with chemical fluid loss control agents based on hydroxyethyl cellulose polymer. The current invention also provides methods for restoring fluid permeability to subterranean formations that have been treated with chemical fluid loss control agents based on hydroxyethyl cellulose polymer. The methods of the current invention contact the subterranean formation with downhole maleic acid solutions for a period of time sufficient to restore fluid permeability to the formation.

Abstract: A method for producing sintered pellets and sintered pellets produced therefrom including mixing a dopant with water and kaolin clay to form substantially round and spherical green pellets and sintering the pellets to form a proppant. The dopant is selected from the group consisting of potassium carbonate, potassium sulfate, potassium chloride, mica, kalsilite, and combinations thereof.

Abstract: Compositions relating to fluid loss control operations are provided. In some embodiments, fluid loss treatment fluid compositions are provided that may comprise ceramic particulate bridging agents, wherein at least a portion of the ceramic particulate bridging agents comprise chemically bonded particulates, a partially depolymerized starch derivative, and a base fluid are provided. In other embodiments, fluid loss treatment fluid compositions are provided comprising ceramic particulate bridging agents, wherein at least a portion of the ceramic particulate bridging agents are substantially insoluble in water; a partially depolymerized starch derivative, and a base fluid.

Abstract: Viscoelastic surfactant (VES) based fluid systems for zone isolation and flow control are effective in water and/or gas shutoff applications. The fluid systems may include brine, a viscosity enhancer, as well as the VES, and optionally a stabilizer for high temperature applications. The stabilizer may be an alkali earth metal oxide, alkali earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, Al2O3, and mixtures thereof. The viscosity enhancer may include pyroelectric particles, piezoelectric particles, and mixtures thereof. The fluid system is easy to pump into the formation, and after pumping, the fluid system will generate very high viscosities to prevent the VES fluid from flowing back to stop undesirable water and/or gas production.

Abstract: It has been discovered that carbonate powders and bicarbonate powders are useful to increase the pH and corrosion resistance of high-density brines, such as zinc bromide brines, without significantly reducing their densities. The carbonates and/or bicarbonates should be water-soluble and may be sodium, potassium, magnesium and/or ammonium carbonates and/or bicarbonates and the like. The carbonates and/or bicarbonates are easily added in powder or other finely divided solid form and are completely dissolved in the brine prior to pumping the brine into a subterranean formation.

Abstract: A water-based drilling fluid having a polymer latex capable of providing a deformable latex film on at least a portion of a subterranean formation has been discovered to provide reduced drilling fluid pressure invasion when used to drill in shale formations for hydrocarbon recovery operations. A precipitating agent such as a silicate or an aluminum complex (e.g. sodium aluminate) is preferably used in conjunction with the polymer. Typically, the water present contains a salt to form a brine, often to saturation, although the invention may be practiced with fresh water. If a salt is employed, it is often helpful to additionally employ a surfactant, such as a betaine, for example.

Abstract: Methods and compositions for use in subterranean operations, and more particularly, additives comprising one or more silicates used to treat tar resident in a well bore, and methods of use, are provided. In one embodiment, the method comprises a method of treating tar resident in a well bore comprising providing a tar-treating additive comprising one or more silicates introducing the tar-treating additive into the well bore; and allowing the tar-treating additive to react with the tar resident in the well bore so as to at least partially reduce the adhesiveness of the tar.

Abstract: An aqueous, viscoelastic fluid gelled with a viscoelastic surfactant (VES) may suspend solids such as proppants, gravel, drilling debris, waste solids and the like with an effective amount of a nano-sized additive including, but not necessarily limited to alkali earth metal oxides, alkali earth metal hydroxides, alkali metal oxides, alkali metal hydroxides, transition metal oxides, transition metal hydroxides, post-transition metal oxides, and post-transition metal hydroxides. The additives may also reduce the amount of VES required to maintain a given viscosity. These viscoelastic surfactant gelled aqueous fluids may be used as treatment fluids for subterranean hydrocarbon formations, such as in hydraulic fracturing, gravel packing and the like. The magnesium oxide, zinc oxide or other nanometer scale-sized additives are at a scale that may provide unique particle charges that use chemisorption, crosslinking and/or other chemistries to associate the micelles and suspend the solids.

Abstract: A monovalent cation containing well fluid composed of an aqueous brine containing at least 0.6 equivalents per liter of a water soluble monovalent cation salt, is substantially free of divalent cations, and an amount of a starch derivative selected such that the well fluid has the following characteristics: (a) a low shear rate viscosity greater than about 5,000 centipoise; (b) a high shear rate viscosity at 511 sec?1 in the range from about 15 to about 70 centipoise measured at 120° F. is described. The fluid may be formulated to be substantially free of xanthan gums and preferably has less than 0.25 lb/bbl of xanthan gum.

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: 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: A scale dissolver fluid for dissolving scale in a subterranean hydrocarbon-bearing formation comprises an effective amount of a scale dissolver formulation and an effective amount of a surfactant for controlling the viscosity of the fluid. In use, formation hydrocarbons act on the surfactant to reduce the viscosity of the fluid so that the fluid selectively invades a hydrocarbon-bearing zone of the formation.

Abstract: Zeolite and Class F fly ash compositions are provided for use as cement-free settable fluids such as settable spotting fluids and cementitious compositions.

Abstract: The present invention relates to the field of additives to enhance hydraulic fracturing used in the production of oil and gas. The additive is an inorganic nitrogen and phosphorus-containing composition that can be added to, or used in conjunction with aqueous or non-aqueous hydraulic fracturing fluids or fracturing fluid adjunctives.

Abstract: A composition and method are given for self-destructive fluid loss additives and filter cakes in wellbores and subterranean formations. The fluid loss additives and filter cakes are formed from a mixture of particulate solid acid-precursors, such as a polylactic acid or a polyglycolic acid, and particulate solid acid-reactive materials, such as magnesium oxide or calcium carbonate. In the presence of water, the solid acid-precursors hydrolyze and dissolve, generating acids that then dissolve the solid acid-reactive materials. The composition is used in oilfield treatments such as drilling, completion and stimulation where it disappears when it is no longer needed without the use of mechanical means or injection of additional fluids.

Abstract: A process for reducing the viscosity of fracturing fluids in downhole oilfield operations is provided. The process comprises contacting a sulfamate stabilized, bromine-based breaker with an aqueous polysaccharide fracturing fluid, with the breaker present in an amount to reduce the viscosity of the fracturing fluid. A composition which comprises a sulfamate stabilized, bromine-based breaker for use in decreasing the viscosity of an aqueous polysaccharide fracturing fluid for use in subterranean oil and gas wells is also provided.

Abstract: A scale dissolver fluid for dissolving scale in a subterranean hydrocarbon-bearing formation comprises an effective amount of a scale dissolver formulation and an effective amount of a surfactant for controlling the viscosity of the fluid. In use, formation hydrocarbons act on the surfactant to reduce the viscosity of the fluid so that the fluid selectively invades a hydrocarbon-bearing zone of the formation.

Abstract: A process for enhancing the productivity of a formation consists of introducing into the formation a viscoelastic fluid which contains at least one surfactant, at least one quaternary amine polyelectrolyte, water, and a non-aqueous solvent. The surfactant forms aggregation structures or vesicles. The fluid, which significantly enhances fluid viscosity and thermal stability, is particularly effective as a diverting fluid to divert an acid treatment package from a high permeability or undamaged portion of a formation to a low permeability or damaged portion of a formation as well as a fracturing fluid. In addition, the fluid is useful for sand control completion.

Abstract: A method to synthesize a chlorine dioxide block remover in a well is described. The method includes dissolving a chlorate aqueous solution and some acidic substances in water and to produce a hydrogen ion. The chlorate aqueous solution and acidic substances are quickly injected into the well by an injection pump, so they react with each other and produce chlorine dioxide. The synthesis of the chlorine block remover in the well removes oil layer blocks induced by polymers and microbes, while reducing the risk of explosion caused by leaked chlorine dioxide, and reducing the corrosion of equipment and pipes caused by chlorine dioxide.

Abstract: Methods of treating subterranean zones and viscous aqueous fluids containing xanthan biopolymer gelling agent and a combination crosslinker and delayed breaker are provided. A viscous cross-linked aqueous treating fluid of the invention comprises water, a xanthan polymer gelling agent, and a combination cross-linker and delayed breaker for said xanthan biopolymer gelling agent.

Abstract: Low concentrations, 1–10% of potassium salt, especially potassium formate, are used in a drilling fluid in oil production. Preferably they are used with guar derivatives, most preferably carboxymethyl hydroxypropyl guar. The concentration of potassium formate is maintained at the desired level by adjusting the potassium formate to maintain a desired Zeta potential in the circulating drilling fluid. The potassium formate/guar derivative composition may be used in the substantial absence of hydrophilic clay additive.

Abstract: A solution containing a compound having the general formula XF.nH2O2, wherein X is K+, Na+ or NH4+ and n is an integer from 1 to 3 (e.g., a peroxysolvate of potassium fluoride compound such as potassium fluoride hydroperoxide (KF.H2O2)) is injected into a subterranean formation in order to increase its permeability, especially with respect to hydrocarbon flow. These compounds serve to dissolve a wide variety of subterranean formation minerals (e.g., siliceous materials as well as carbonaceous materials). Potassium hydrofluoride (KHF2), can be employed with these compounds to produce particularly efficacious subterranean formation treatment solutions.

Abstract: Xanthan gels hydratable in brine, methods of making these xanthan gels, and methods of using these compositions in subterranean formation applications, such as gravel packing, are provided herein.

Abstract: Viscous well treating fluids and methods of treating subterranean zones penetrated by well bores are provided. The viscous fluids are basically comprised of water, a gelling agent and a delayed viscosity breaker comprising pentanedione peroxide.

Abstract: It has been discovered that carbonate powders and bicarbonate powders are useful to increase the pH and corrosion resistance of high-density brines, such as zinc bromide brines, without significantly reducing their densities. The carbonates and/or bicarbonates should be water-soluble and may be sodium, potassium, magnesium and/or ammonium carbonates and/or bicarbonates and the like. The carbonates and/or bicarbonates are easily added in powder or other finely divided solid form.

Abstract: There is described a fracturing fluid comprising a polar base, 0.1-5.0% of a mid-molecular weight polyacrylate, and an activator for ionizing the polyacrylate to a hydroscopic state.