Abstract: Wellbore fluid containing a base fluid and a particulate bridging agent comprised of melamine. A method is also described of forming a removable filter cake on the walls of a wellbore that penetrates a porous and permeable rock formation by placing in the wellbore a wellbore fluid containing a base fluid and melamine, and permitting the melamine to deposit from the wellbore fluid onto or into the walls of the wellbore to form the filter cake, whereby fluid loss to the formation through the removable filter cake is reduced.

Abstract: Provided herein are methods and compositions that include a method comprising contacting a metal surface with an acidic fluid comprising a corrosion inhibitor that comprises a reaction product formed from a direct or an indirect reaction of an aldehyde with a thiol and/or an amine functionalized ring structure. A composition provided includes an acidic treatment fluid that comprises an aqueous-base fluid, and acid, and a corrosion inhibitor that comprises a reaction product formed from a direct or an indirect reaction of an aldehyde with a thiol and/or an amine functionalized ring structure.

Abstract: Friction reducing compositions for use in well treatment fluids generally include an aqueous fluid; a polymeric friction reducer; and 3,5-dimethyl-1,3,5-thiadiazinane-2-thione. It has been found that the combination of the polymeric friction reducer; and 3,5-dimethyl-1,3,5-thiadiazinane-2-thione unexpectedly and synergistically increases friction reduction and inversion behavior, where applicable. Also disclosed are methods for the fracturing of a subterranean hydrocarbon bearing formation to stimulate the production of the hydrocarbons by injecting the friction reducing composition.

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: Provided is an anticorrosive composition for use in aqueous salt solutions. The composition contains an antimony compound and at least two other components selected from morpholine derivatives, acetylenic alcohols, ascorbic acid derivatives, and selenium compounds. The composition is particularly useful for inhibiting corrosion of metallic surfaces of drilling devices or refrigeration systems that are in contact with salt brines at elevated temperatures.

Abstract: Imidazoline dimer-type compounds which are prepared by the reaction of dimer fatty acid and a dialkylene triamine, such as diethylenetriamine (DETA), are useful for corrosion inhibition in water-containing fluids contacting metal, particularly fluids containing CO2 and/or H2S. When the reaction is conducted with molar excess of the polyamine, the resulting imidazoline dimer or oligomer is surprisingly more effective at corrosion inhibition than conventional monomeric imidazoline. Also unexpected is the better water solubility of the reaction product as compared with the conventional monomeric imidazoline.

Abstract: Environmentally friendly compounds for corrosion inhibition and hydrocarbonaceous deposit removal and methods using such compounds are disclosed and claimed. The compounds are derivatives of heterocyclic bis-quaternary molecules having an amido moiety and are applicable to a variety of oil and gas operations.

Abstract: Disclosed are imidazoline-based foamers and corrosion inhibitors for treatment of oil and gas wells for enhanced production. The invention also includes methods of foaming a fluid by introducing the disclosed foamers to oil and gas wells.

Abstract: An ionic liquid may be used to inhibit the swelling and/or disintegration of clay in a subterranean formation. A subterranean clay-containing formation may be treated with the ionic liquid by contacting the formation with a well treatment composition containing the ionic liquid dispersed or dissolved in a carrier fluid. Damage to the formation caused by contact with the well treating composition is reduced or substantially eliminated.

Abstract: A formulation containing a copolymer derived from a cationic monomer effectively inhibits and controls the formation of inorganic scales. Suitable copolymers include those comprising an acrylamide unit and a quaternary ammonium salt group, and optionally an acrylate and/or nitrogen heterocyclic monomer including those wherein the quaternary ammonium salt is a unit of the formula: wherein R is methyl or hydrogen; R4 is a C1 to C6 alkyl group, optionally substituted with halogen, hydroxyl and alkoxy groups, X is halogen; and R1, R2 and R3 are independently selected from the group consisting of alkyl and alkoxy groups. Suitable nitrogen heterocyclic compounds include N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, N-vinylcaprolactam, N-vinylimidazole and N-vinylpyridine.

Abstract: A method for reducing acid corrosion and products of acid corrosion in a thermal cracking plant, the acid corrosion products being compounds of iron, chromium, nickel, lead, cadmium, manganese, mercury, magnesium, calcium, sodium, copper, zinc, lead, molybdenum, and aluminum, the improvement comprising introducing ethylene diamine into at least one process stream of the plant.

Abstract: The present invention relates to compounds of formula (1) and the salts thereof which correspond to formula (2). In the formulae, A is C2- to C4-alkylene, x is a number from 1 to 100, y is a number from 1 to 4, and R is a cation. The compound of formula (1) and/or formula (2) forms a persistent film on metal surfaces, particularly on metal surfaces under stress in metal working and in the operation of crude oil and natural gas processing.

Abstract: It has been discovered that ammonia and amines are useful to increase the pH and corrosion resistance of high density brines, such as zinc bromide brines, without significantly reducing their densities. The ammonia or amine additive is preferably incorporated by contacting the brine with the additive which is in the vapor phase. Optionally, a substituted carboxylic acid, such as hydroxy carboxylic acid, may be used to increase the amount of ammonia or amine that can be included in the high density brine without precipitation of salts.

Abstract: An environmentally friendly corrosion inhibiting formulation for the oil-water interface of pipe lines and oil well drilling systems which is prepared pursuant to a process including the steps of reacting an acid selected from the group consisting of a fatty acid anhydride and a 21 carbon dibasic acid with an amine or imidazoline to form a corrosion inhibitor consisting essentially of a fatty acid derivative; dissolving the inhibitor in a fatty acid oil or ester selected from the group consisting of soybean oil or methyl soya ester; adding water dispersing agents consisting of sulfonates and a long chain ethoxylated alcohol; and adjusting the viscosity with an alcohol comprising isopropanol.

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: A low toxic, biodegradable, water soluble and dispersant series of corrosion inhibitors are described. The method of inhibiting corrosion in aqueous medium by incorporating the inhibitor in PPM is provided. The corrosion inhibitor compromises an acrylic acid and chloroacetic acid adduct of 2-substituted imidazolines or primary, secondary or tertiary amines with carbon chain of twelve to twenty-two saturated or unsaturated carbon atoms. The molar ratio of acrylic acid to chloroacetic acid was methodically changed while keeping the concentration of imidazoline or the amine a constant. The product is made water soluble by raising the pH to 8-9 at the end of the synthesis by adding aqueous sodium hydroxide.

Abstract: A method for recovering oil in a reservoir by generating chemical microexplosions in the reservoir. The invention treats the hydrocarbon-bearing reservoir by decomposing in situ at least one PEH-3CO, thereby generating heat, shock, and CO2. A preferred method comprises the steps of depositing PEH-3CO into the formation and depositing an acid into the formation to cause the PEH-3CO to decompose and generate heat and gas.

Abstract: A method for recovering oil in a reservoir by generating chemical microexplosions in the reservoir. The invention treats the hydrocarbon-bearing reservoir by decomposing in situ at least one imidazolidone derivative, thereby generating heat, shock, and CO2. A preferred method comprises the steps of depositing an imidazolidone derivative into the formation and depositing an acid into the formation to cause the imidazolidone derivative to decompose and generate heat and gas.

Abstract: Liquids comprised solely of anions and cations (“ionic liquids”) are disclosed as novel components of fluids (and techniques relying upon those fluids) for stimulation of hydrocarbon wells. In particular, the fluids disclosed are useful in matrix acidizing. Formation of the ionic liquids of the present Invention is highly exothermic, hence the heat generated can be used, for instance, to melt de-watered drilling fluid in the near-wellbore region of the formation. Further, reaction of the ionic liquids with water results in acid generation; this acid can be used to, for instance, to stimulate a formation, either by conventional matrix acidizing or fracture acidizing. In addition, certain preferred species of the ionic liquids of the present Invention are highly stable solvents, hence they can be used as carrier fluids for highly reactive super acids (e.g., SbF5+HF) in connection with matrix acidizing.

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: In the removal of particulates from a wellbore, such as in air drilling for hydrocarbon recovery, a mixture of an amphoteric foaming agent and, typically, an anionic surfactant is employed. An aqueous solution thereof having a pH of at least 9.5 is used to generate a foam for removing the particulates; then the foam is collapsed by the introduction of acid to reduce the pH below about 4, the particles are removed mechanically, the pH is restored to greater than 9.5, and the foaming solution is returned to the wellbore. The solution may be used several times; partial losses of foaming agent in the process may be easily replenished with each cycle. Cationic surfactants may be used instead of anionic, with foaming and foam collapse being controlled at opposite pH's. Savings are realized in water, drilling chemicals, and settling pits and the like for removing particulates from the foam.

Abstract: An asphaltene removal composition comprising an alkyleneamine-fatty acid condensation reaction product and one or more polar aprotic high dielectric constant solvents is useful for removing and inhibiting asphaltene deposits from wells, pipelines and associated equipment.

Abstract: A method for the inhibition of scale deposition on the surfaces of a well coproducing oil and scale forming brines comprising injecting into the well reservoir an acidic aqueous solution at a first pH containing dissolved therein a scale inhibitor, multivalent metal ions, and a heat-sensitive pH-increasing substance containing no more than 10 carbon atoms, which decomposes at elevated temperatures liberating an alkaline compound such that the solution is inherently heated by the higher ambient reservoir temperature to a temperature at which the alkaline compound is liberated from the heat-sensitive substance thus raising the pH of the solution to a point at which a sparingly soluble multivalent metal salt of the scale inhibitor is phase separated from the solution on the porous surfaces of the reservoir rock formation, providing for a slow release of inhibitor into the produced brines when the well is in its production phase.