Abstract: This invention relates to novel compositions and methods whereby a carboxylate based brine solution is used in drilling and/or well bore treating operations to inhibit corrosion of fluid handling equipment. In one embodiment of the invention the carboxylate based brine solution consists of a carboxylate salt dissolved in water. This brine solution is used to prepare halide-free drilling fluids. Use of halide-free drilling fluids inhibits corrosion stainless steel surfaces of fluid handling equipment. In an alternative embodiment of the present invention a mixed salt brine containing a carboxylate salt and a halide salt is provided for use in a drilling and/or well bore treating operations.

Abstract: The present invention relates to a gelled hydrocarbon fluid useful as a fracturing fluid in subterranean formations comprising at least one gelling agent which is a salt of a carboxylic acid having from about 6 to about 30 carbon atoms. An activator which is a difunctional and/or trifunctional carboxylic acid is preferably added to control gel time.

Abstract: A mutual solvent for use in oil and gas well operations comprising 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate and/or 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, a coupling solvent, and an acid stable surfactant. The coupling solvent is selected from ethylene glycol monobutyl ether; diethylene glycol monobutyl ether; propylene glycol monomethyl ether acetate; propylene glycol monomethyl ether; C1-C5 alkyl alcohol; and mixtures thereof. The invention also relates to an emulsion for use in oil and gas well operations comprising an aqueous acid or acid-salt brine solution and the mutual solvent as described above. An emulsion according to the invention is stable, non-toxic, and effectively removes asphaltenic and paraffinic hydrocarbons from drilling equipment and oil and gas wells.

Abstract: An encapsulated breaker slurry composition for reducing the viscosity of a fracturing fluid. The slurry has a flashpoint above 93° C., and the liquid of the slurry does not facilitate release of the breaker from the coating. Methods of using the slurry composition are also described.

Abstract: A composition and method for acidizing a formation in the presence of ferric ion, free sulfur and/or sulfides is disclosed. The composition employs a ferric ion reducing agent and a sulfide reactant separately or in combination. The ferric ion reducing agent is a thioalkyl acid. The sulfide reactant compounds include &agr;-diketones and saturated and &agr;-unsaturated cyclic ketones. In another aspect, the reducing activity of the thioalkyl acid is accelerated by the presence of a catalytic quantity of a compound or mixture of compounds which yield in acid solution cuprous ion, cupric ion or combinations thereof with iodide ion.

Abstract: A method of fracturing a subterranean formation, in which subterranean formation being in fluid communication with the surface includes creating a fracture in said subterranean formation, said fracture having more than one fracture faces; and injecting into said fracture an encapsulated formation etching agent, wherein said encapsulated formation etching agent includes a formation etching agent and an encapsulating agent and wherein said formation etching agent etches the fracture faces of the fracture so as to form a flow channel in said formation. The formation etching agent may be selected from mineral acids and mixtures thereof, organic acids and mixtures thereof, mineral acids and mixtures of mineral acids mixed with gelling agent, organic acids and mixtures of organic acids mixed with gelling agent, water soluble hydroxides and mixtures of water soluble hydroxides, and water soluble hydroxides and mixtures of water soluble hydroxides mixed with gelling agent.

Abstract: The invention relates to a synergistic mixture of A from 5 to 99% by weight of a carboxylic acid having more than 4 carbon atoms, an ethercarboxylic acid containing C18-C22-alkyl, C18-C22-alkenyl or C6-C18-alkylaryl substituents, an amidocarboxylic acid, or mixtures thereof, B from 1 to 95% by weight of a phosphoric mono- or diester, or mixtures thereof, which is substituted by C18-C22-alkyl, C18-C22-alkenyl, C6-C18-alkylaryl or alkoxylated groups, where the sum of components A and B is 100% by weight, to crude oils containing such mixtures, and to a process for dispersing asphaltenes in crude oils.

Abstract: An esterification process and the products resulting from it which achieves a mixture of secondary esters which are effectively used with invert drilling muds, the process involving the addition of one or more C1-C5 carboxylic acids and one or more C3-C22 olefins in the presence of an acid catalyst.

Abstract: A process is provided for reducing the permeability of or fluid mobility within a carbonate-containing treatment region in or proximate to a hydrocarbon-bearing formation below an earthen surface penetrated by a well bore. The process is initiated by preparing a gelation solution at the earthen surface which includes an acrylamide polymer, a crosslinking agent, a stabilizing agent and an aqueous solvent. The stabilizing agent is an acid additive, acidic pH buffer system, or delayed acid generator. The crosslinking agent is a chromium(III) complex having one or more chromium(III) cations and one or more carboxylate anions. The gelation solution is injected into the well bore and displaced into the treatment region where it is gelled in situ to form a gel which substantially reduces the permeability of or fluid mobility within the treatment region.

Abstract: An encapsulated breaker is enclosed within a hydrolytically degradable polymer coating. Compositions containing this encapsulated breaker, methods of making and methods of use are also described.

Abstract: A gel-breaking/gel-inhibiting composition containing at least one carboxylic acid or salt thereof is dispersed in a hydrophobic carrier fluid to break down a cross-linked polymer gel or inhibit the gelation of a polymer gel used in plugging in permeable subterranean formations containing oil-bearing zones and water-bearing zones. The composition may be used to selectively restore permeability to oil-bearing zones in formations containing a cross-linked polymer gel or to inhibit gelation in an oil-bearing zone by injection into the oil-bearing zone prior to or after treatment of the formation containing the oil-bearing zone with an aqueous polymer solution.

Abstract: An esterification process and the products resulting from it which achieves a mixture of secondary esters which are effectively used with invert drilling muds, the process involving the addition of one or more C.sub.1 -C.sub.5 carboxylic acids and one or more C.sub.3 -C.sub.22 olefins in the presence of an acid catalyst.

Abstract: A composition for and an improved process of, enhancing petroleum recovery from a petroleum reservoir by injecting said composition into the reservoir through a wellbore are provided. The aqueous composition is derived from a concentrate which includes a defoaming agent, a demulsifying agent, and optionally a stabilizing agent suitable for stabilizing the concentrate as an aqueous emulsion. In one embodiment, the defoaming agent is dispersed in carrier solvent and the concentrate further includes an emulsifying agent suitable for emulsifying the carrier solvent in water. The composition is preferably injected at a high pumping rate directly into the formation through the tubing-casing annulus and allowed to permeate into the reservoir surrounding the wellbore before oil production commences. The composition and method are particularly suited for used in conjunction with steam injection oil recovery techniques.

Abstract: Corrosion is inhibited in hydrochloric acid solutions used to acidize wells, by adding to the solutions a corrosion inhibiting composition comprising cinnamaldehyde or a substituted cinnamaldehyde together with a reaction product of a C.sub.3-6 ketone such as acetophenone, thiourea or a related compound, formaldehyde and hydrochloric acid.

Abstract: Subterranean oil-bearing formations are treated with aqueous acid solutions which include an effective amount of an ester or salts of sulfonated fatty acids, which exhibits both antisludge and demulsification properties.

Abstract: A method of formulating a zirconium lactate compound is accomplished by combining in solution lactic acid or a lactate salt with zirconium carbonate. The reacting solution forms zirconium lactate and carbon dioxide which is evolved as a gas from the solution. This eliminates the need to filter or wash the zirconium lactate in order to remove undesirable by-products. The zirconium lactate can be used as a crosslinking agent for crosslinking aqueous polymer gels used in such things as fracturing fluids for fracturing subterranean formations of oil and gas wells.

Abstract: A gelling composition comprises a multivalent metal compound-crosslinkable polymer such as a carboxylate-containing polymer, a multivalent metal compound such as a zirconium compound, a liquid, and a pH-lowering agent such as carbon dioxide wherein the composition is prepared by combining the polymer and multivalent metal compound to form a mixture and, thereafter, introducing carbon dioxide to the mixture. A process for treating a subterranean formation can comprise the steps of: (1) combining a polymer with a multivalent compound to form a mixture; (2) introducing the another mixture into a subterranean formation; and (3) introducing carbon dioxide into the mixture.

Abstract: A process for altering the permeability of a subterranean formation comprises injecting into the subterranean formation a gelling composition which comprises a carboxylate-containing polymer, a crosslinking agent, and a liquid such as a produced brine wherein the polymer forms a gel in the formation, in the presence of the crosslinking agent. The polymer can have a molecular weight of from about 10,000 to about 30,000,000, contain about 0.01 to about 10 mole % of a carboxylate group, and be present in the gelling composition in the range of from about 100 to about 100,000 mg per liter of the composition.

Abstract: The invention is an effective, easy to produce, and economical corrosion inhibitor which can be used in a variety of environments. The corrosion inhibitor of the present invention is the salt of certain tertiary amines. The corrosion inhibitor is the reaction product of one or more tertiary amines and certain carboxylic acids, preferably a mixture of mercaptocarboxylic and carboxylic acids.

Abstract: A chemical additive for cleaning a well drilling system and equipment includes an alcohol, preferably a terpene, and either an ether amine or a base fluid or combination of the two. The additive can be mixed with an aqueous solution that may be a water, salt or brine solution.

Abstract: A composition and method for use in freeing differentially stuck pipes is presented, comprising a hydrocarbon, acetic acid and a surfactant. The composition frees stock pipes quickly, thus reducing down-time during the process of drilling a subterranean well.

Abstract: A method for forming a stable emulsion of a viscous hydrocarbon in an aqueous buffer solution includes the steps of: providing a viscous hydrocarbon containing an inactive natural surfactant and having a salt content by weight of less than or equal to about 15 ppm and having a water content by weight of less than or equal to about 0.1%; forming a solution of a buffer additive in an aqueous solution to provide a basic aqueous buffer solution, the buffer additive being operative to extract and activate the inactive natural surfactant from the viscous hydrocarbon; and mixing the viscous hydrocarbon with the aqueous buffer solution at a rate sufficient to provide an emulsion of the viscous hydrocarbon in the aqueous buffer solution, whereby the buffer additive extracts the inactive natural surfactant from the viscous hydrocarbon into the aqueous buffer solution and activates the inactive natural surfactant so as to stabilize the emulsion. According to the invention, the buffer additive is a water soluble amine.

Abstract: A gelling composition and a process for wellbore treatment comprising injecting the composition into reservoirs are disclosed wherein the composition comprise a produced brine; a water-soluble polymer such as, for example, polyacrylamide; a crosslinker such as, for example, a complexed zirconium compound; and optionally a complexing ligand such as, for example, lactic acid.

Abstract: A method is provided to fracture a subterranean formation along with a fracturing fluid useful in this method, the method comprising the steps of: a) providing a fracturing fluid, the fracturing fluid is an aqueous solution having an initial pH greater than about 8 and comprising a polysaccharide, a source of borate in an amount that is effective to crosslink the polysaccharide at a pH greater than 8, an oxidative breaker, and a precursor that hydrolyzes in an amount that is effective to lower the pH of the fracturing fluid after a time period that is greater than about one half hour and less than about two days; b) injecting the fracturing fluid into the formation at a pressure the is effective to fracture the formation and force at least a portion of the fracturing fluid into the fracture; and c) permitting the precursor to hydrolyze and thereby lowering the pH of the fracturing fluid to a pH that is less than about 8.

Abstract: A hydrochloric acid acidizing composition for treating a subterranean formation penetrated by a well bore to increase the production of desired materials (e.g., hydrocarbons) therefrom that includes a corrosion inhibitor for protecting both ferrous based alloy surfaces (e.g., low alloy steel surfaces) and titanium based alloy surfaces associated with the treatment from corrosion by the acid. The corrosion inhibitor includes an effective amount of a first inhibitor component for inhibiting corrosion of ferrous based alloys, the first inhibitor component including at least one chemical reducing compound, and an effective amount of a second inhibitor component for inhibiting corrosion of titanium based alloys, the second inhibitor component including at least one source of molybdate ions such as sodium molybdate. A method of treating a subterranean formation penetrated by a well bore to increase the production of desired materials therefrom is also provided.

Abstract: Fracturing fluids for hydraulically fracturing oil and gas bearing subterranean formations to increase flow of formation fluids into wells using a periodate or a metaperiodate salt as the viscosity breaker. The fracturing fluids are particularly advantageous when used in conjunction with curable resin-coated proppants and for fracturing subterranean formations which are at temperatures between about 50.degree. F. and about 120.degree. F., in conjunction with both uncured resin-coated proppants and other types of proppants.