Abstract: A method of removing the filter cake formed from invert emulsion compositions including an oleaginous, a non-oleaginous and an acid sensitive surfactant in an oil and gas well are disclosed. The acid sensitive surfactant is selected so that the invert emulsion can be broken and residual filter cake solids made water-wet upon the addition of an acidic wash fluid to the well.

Abstract: The present invention relates to an oil-based drilling fluid, a continuous phase for an oil-based drilling fluid, and additives for an oil-based drilling fluid. The drilling fluid, the continuous phase of the drilling fluid, and the additives for the oil-based drilling fluid are characterized by non-fluorescence (defined as a fluorescence intensity of 800 or less) when exposed to ultraviolet light. The continuous phase of the drilling fluid is composed of synthetic hydrocarbons selected from the group consisting of oligomers synthesized from one or more alphaolefins containing a C.sub.2 to C.sub.14 chain length, wherein the oligomers have an average molecular weight of from 120 to 100, and additives. The additives of the continuous phase include surfactants, wetting agents and/or emulsifiers.

Abstract: An oil in water dispersion composition is disclosed that comprises a mixture of water and(A) an overbased non-Newtonian colloidal disperse system comprising(1) solid metal-containing colloidal particles predispersed in(2) a disperse medium of at least one inert organic liquid and(3) at least one member selected from the class consisting of organic compounds which are substantially soluble in the disperse medium, where the molecules of said organic compound have polar substituents and hydrophobic portions;(B) a water soluble associative thickener comprising a base-neutralized copolymer having copolymerized therein about 90 to about 99 mole percent of a carboxyl-containing, ethylenically unsaturated hydrocarbon and about 1 to about 10 mole percent of a nonionic surfactant acrylate having the formula: ##STR1## wherein R.sup.1 is hydrogen or methyl, R.sup.

Abstract: An oil-in-water emulsion composition is disclosed which comprises a mixture of water and(A) at least one oil comprising(1) a natural oil or synthetic triglyceride of the formula ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 are independently saturated or unsaturated aliphatic groups that contain from about 7 to about 23 carbon atoms;(2) a synthetic ester base oil comprising the reaction of a monocarboxylic acid or a dicarboxylic acid or an aryl carboxylic acid;(3) an olefin;(4) a polyolefin;(B) at least one phosphite ester of the formula ##STR2## wherein R.sup.11 and R.sup.12 are independently aliphatic, aryl or aliphatic substituted aryl groups that independently contain from 6 to 30 carbon atoms; and(C) at least one emulsifier.

Abstract: An improved drilling fluid with enhanced anti-settling properties useful for all types of drilling systems is described. The invention includes a process for providing anti-settling properties to both oil and invert oil (i.e., water in oil emulsion) based fluids as well as the additive itself. The drilling fluid drilling mud invention contains at least one reaction product of which the reactants comprise an alkoxylated aliphatic amino compound and an organic polycarboxylic anhydride or acid and a rheologically active clay-based material.

Abstract: A water based drilling fluid which is environmentally non-toxic containing a sodium alkylsufosuccinate and well drilling additives, said sodium alkylsulfosuccinate is water dispersible and imparts anti-bit balling, lubricity and environmentally non-toxicity properties to said drilling fluid and does not precipitate in the presence of the said well drilling additives.

Abstract: This invention relates to a composition comprising a mixture of a brine and a liquid oil, and (A) an emulsifying amount of (i) at least one reaction product of a hydrocarbyl-substituted succinic acylating agent, and at least one of (a) ammonia, (b) an alcohol, or (c) an amine, or at least one salt of the reaction product; or (ii) at least one reaction product of a hydroxyaromatic compound, an aldehyde, and an amine, and (B) at least one surfactant selected from the group consisting of a polyoxyalkylene amine, a polyoxyalkylene amide, a polyoxyalkylene alcohol, a polyoxyalkylene phenol, a polyoxyalkylene ester, a fatty acid salt, an amine or an alkaline earth or transition metal sulfonate, or a reaction product of a hydroxyamine or a polyalkylenepolyamine with an acylating agent selected from the group consisting of a fatty monocarboxylic acylating agents, a dicarboxylic acylating agent other than a succinic acylating agent, and a tricarboxylic acylating agent.

Abstract: Increased foam quality and resistance to hydrocarbon defoaming for foams used in well boring and stimulation processes as well as secondary and tertiary oil recovery is obtained using imidazoline-based amphoacetates of higher purity, containing essentially negligible amounts of unalkylated amido amines, lower amounts of glycolic acid salts and monochloroacetate salts.The higher purity amphoacetates can be obtained via processes utilizing precise pH control during the reaction of imidazoline, or its open-chain derivatives, with alkylating agents, e.g. sodium monochloroacetate. These higher-purity amphoacetates contain essentially fully alkylated products and lower amounts of glycolic acid derivatives, even though a ratio of monohaloalkylate to substituted imidazoline, or its open-ring derivative, of less than 1.5:1.0 and close to 1.0:1.0 is used.

Abstract: The present invention provides nonionic alkanolamides which may be added to drilling fluids in order to minimize hydration and prevent erosion loss of water-sensitive shale substrates. Preferred alkanolamides are acetamide mono- and diethanolamines.

Abstract: The present invention provides amphoteric acetates, diacetates, and glycinates which may be added to drilling fluids in order to minimize hydration and prevent erosion loss of water-sensitive shale substrates.

Abstract: New compositions are disclosed that are useful for the prevention of sludge or emulsions during the drilling or workover of producing oil wells. These compositions are comprised of a N,N-dialkyl amide of a fatty acid, a hydrocarbon solvent for petroleum and a mutual oil/water solvent. Also taught and claimed is a method of preventing such sludge or emulsion formation or of breaking the same after it is formed.

Abstract: The invention relates to clay stabilizing agents for use in an alkaline water-base fluid such as a drilling mud and the use of such clay stabilizing agents in the drilling of wells. The clay stabilizing agent comprises a polyfunctional polyamine reaction product prepared by the reaction of a polyamine base reactant with urea or a dialkylcarbonate or by reaction with urea and a dialkylcarbonate. The stabilizing agent is subject to subsequent acidification to reduce the pH thereof to a value of about 7 or less. The polyamine base reactant is selected from the group consisting of an aliphatic polyamine, a polyaliphatic polyamine, a heterocyclic polyamine, an alkylalkanol polyamine and mixtures thereof. Specifically, the base reactant comprises an aliphatic polyamine selected from the group consisting of ethylenediamine, diethylenetriamine, tetraethylenetetramine, and tetraethylenepentamine and mixtures thereof.

Abstract: A method and coating composition for producing protective coatings on metal surfaces of tubular goods, equipment and so forth used in processes associated with oxidative environments to inhibit corrosive effects of the oxidative environments thereon. The coating composition includes an aqueous liquid carrier and a corrosion inhibiting combination of a specific condensation product and an antimony compound. The antimony compound is activated by the condensation product and enhances the degree of protection achieved.

Abstract: Improved mud additive compositions are provided which are especially formulated to control hole enlargement due to salt bed erosion during drilling, and to assist in solubilization of deposited salt during well operations. The compositions include a first ingredient such as sodium or potassium ferrocyanide and mixtures thereof, and a second ingredient such as the trisodium salt of nitrilotriacetic acid and alkali metal citrates. The first ingredient is generally present at a level of from about 50-95% by weight in the particulate, dilutable form of the invention, whereas the second ingredient is present at a level of from about 5-50% by weight. The compositions hereof may be added to drilling mud during drilling operations or to fresh water for removing salt depositions.

Abstract: The present invention relates to a method comprising the steps of introducing into a well borehole a composition, comprising water and an amount, sufficient to reduce drilling torque, prevent sticking or twisting of a pipe during drilling, or release a stuck pipe in a well borehole, of (A) at least one reaction product of (A-1) at least one hydrocarbyl-substituted carboxylic acylating agent and (A-2) at least one amine-terminated polyoxyalkylene having a number average molecular weight from about 600 to about 10,000, or at least one salt of the reaction product, and drilling the well borehole. Drilling torque, twisting and sticking of the pipe during drilling and releasing of stuck pipe in a well borehole are all effectively controlled by the methods and compositions of the present invention.

Abstract: In a first embodiment, the invention relates to the use of basic amine compounds of pronounced oleophilic character and at most limited solubility in water, which are capable of forming salts with carboxylic acids, as an additive for w/o invert drilling muds which contain in the continuous oil phase ester oils and, together with the disperse aqueous phase, emulsifiers, weighting agents, fluid loss additives and, if desired, other additives for protecting the drilling muds against unwanted thickening in use or for improving their flowability. In another embodiment, the invention relates to w/o invert drilling muds which are suitable for the improved offshore development of oil and gas sources and which are characterized by the presence of basic amine compounds of pronounced oleophilic character which are capable of forming salts with carboxylic acids.

Abstract: The present invention relates to an improved continuous phase for an oil based drilling fluid and specifically a synthetic hydrocarbon continuous phase which is non-polluting and minimally toxic. The invention provides excellent drilling fluid properties under a wide variety of drilling conditions. The synthetic hydrocarbons are selected from the group consisting of branched chain oligomers synthesized from one or more olefins containing a C.sub.2 to C.sub.14 chain length and wherein the oligomers have an average molecular weight of from 120 to 1000. In the drilling fluid compositions, suitable emulsifiers, wetting agents, viscosifiers, weight materials and fluid loss additives are utilized in conjunction with water and/or a brine phase for the desired rheological properties.

Abstract: This invention relates to drilling fluid additives that suppress clay swelling within a subterranean well and to methods for controlling clay swelling during the drilling of a subterranean well. Aliphatic polyamines and aliphatic acids react to form polyamides and polyamino acids that are water soluble, that have molecular weights of less than about 1000, and that have low toxicity levels. The polyamides and polyamino acids are added to water base drilling fluids which are circulated throughout a well.When X in the acid is a hydroxyl group, the polyamide products have the following general structure: ##STR1## When X in the acid is a halogen such as chlorine, the polyamino acid products have the following general structure: ##STR2## The drilling fluid additives and the method of controlling clay swelling provide for improved control of the rheological properties of drilling fluids along with an increased environmental compatibility.

Abstract: A drilling fluid includes water, bentonite, a weighting agent, and an additive comprising a water-soluble polycondensate containing phosphorous and nitrogen such as phosphorylated-urea-formaldehyde or phosphorylated-melamine-formaldehyde. Such additives provide the desired rheological and filtration loss properties as well as thermal and shear stability. The additives are prepared by reacting phosphorous acid, urea and formaldehyde according to a Mannich-type reaction.

Abstract: A treatment fluid additive and method for treatment of subterranean formations to minimize formation permeability damage as a result of formation contact by the treatment fluid, wherein the fluid treatment additive is a formation control additive of the general formula: ##STR1## wherein R is independently a C.sub.1 to C.sub.4 alkyl, halogen and/or hydroxyl substituted alkyl and at least one R is a C.sub.1 to C.sub.4 halogen or hyroxyl substituted alkyl, and X.sup.- is selected from the group consisting of chloride, fluoride, bromide, iodide, nitrate, nitrite hydroxide, and sulfate.

Abstract: This invention relates to a composition suitable for use in process for the removal of sulfides, especially hydrogen sulfide from a feed contaminated therewith. The composition comprises an aqueous solution of a chlorite and a corrosion inhibitor which is an amphoteric ammonium compound of the formula ##STR1## as herein defined. The inhibitor mitigates problems of corrosion associated with chlorite scavengers.