Abstract: Compositions of oil-based biodegradable drilling fluids are described, the compositions comprising an oil phase composed by methyl esters of soybean oil fatty acids, an aqueous phase finely dispersed in the oil phase by specific emulsifiers and several other additives having specific functions for providing suitable performance to the finished drilling fluid composition. The process to manufacture the inverted emulsion and the drilling process that employs the compositions of the invention are described too.

Abstract: A method for drilling, running casing in, and/or cementing a borehole in a subterranean formation without significant loss of drilling fluid is disclosed, as well as compositions for use in such method. The method employs a drilling fluid comprising a fragile gel or having fragile gel behavior and providing superior oil mud rheology and overall performance. The fluid is especially advantageous for use in deep water wells because the fluid exhibits minimal difference between downhole equivalent circulating density and surface density notwithstanding differences in drilling or penetration rates. When an ester and isomerized olefin blend is used for the base of the fluid, the fluid makes an environmentally acceptable and regulatory compliant invert emulsion drilling fluid. The fluid preferably contains no organophilic clays.

Abstract: A superior powder form of a metallic soap for enhancing the properties of an invert emulsion drilling fluid may be prepared by a dry process saponification reaction. The process includes mixing a source of metal cations with the product of a Diels-Alder reaction of dienophiles with fatty acids and/or resin acids and allowing the mixture to react. Heating the mixture increases the rate of reaction. The solid product is ground to form a powder. The properties of the drilling fluid that may be improved by adding the soap include filtration control, fluid loss control, emulsification and emulsion stability, and electrical stability.

Abstract: A temperature-stable, non eco-toxic oil-base well fluid that is particularly suitable for high pressure/high temperature drilling comprises an emulsification system comprising at least one superamide that may or may not be polyalkoxylated, optionally associated with a non-ionic co-surfactant. The oil-base well fluid comprising such a system can be used at temperatures of up to about 200° C. due to the production of highly temperature-stable reverse emulsions.

Abstract: The present invention relates to a method and to a fluid for drilling or workover in a well running through a porous permeable formation, wherein a water-based well fluid circulates in said well. In the method, at most 3% by weight of a composition obtained from fat, or an oil, and an alcohol, is added to the fluid in addition to the conventional constituents for such a fluid, the chain lengths of the acid and alcohol parts being chosen such that the ester thus obtained has sufficient dispersion in water, compatibility with said constituents, does not form an emulsion with the reservoir oil and adsorbs sufficiently on the porous formation.

Abstract: An organic based emulsion-breaking formulation for use in treating well bores drilled in oil-bearing mud that is not eco-toxic and is optimally compatible with formation fluids comprises: as the emulsion-breaking agent, at least one constituent selected from non-ionic amphiphilic compositions obtained by reacting at least one polymerized vegetable oil with at least one aminoalcohol and alkyl esters (for example C1 to C8) of fatty acids derived from natural, vegetable or animal oils; optionally, at least one wetting agent selected from anionic surfactants; and optionally at least one solvent; the assembly being as a mixture in an organic base. Such a formulation can be weighted by mineral fillers.

Abstract: Suspensions are provided of water-soluble materials in non-aqueous carrier fluids using suspension agents that include thixotropic agents and, optionally, organophilic clays. Methods of forming such suspensions are provided. Methods are also provided for using such suspensions to prepare aqueous solutions, in particular thickened aqueous solutions, in particular for use in oilfield treatments.

Abstract: Self-generating foamed fluids for circulation through a well during drilling operations and methods for circulating such self-generating foamed drilling fluids are provided for. The drilling fluid comprises an aqueous solvent, a polymer, a surfactant, a first foam generating agent, and a second foam generating agent. The first and second foam generating agents react to generate a gas within the drilling fluid and thereby to foam the drilling fluid. Preferably, the foam generating agents are selected such that they react to generate carbon dioxide. Preferably a base fluid comprising excess amounts of only one of the foam generating agents is pumped into the drill string using a hydraulic pump. The other foam generating agent then is injected in a controlled manner downstream of the circulation pump such that the drilling fluid is foamed after being pumped for circulation through the well. The novel drilling fluids preferably have a density of from about 5.8 lb/gal to about 0.

Abstract: Drilling, completing or workover of a well, particularly an oil and/or gas well, is carried out using a fluid which includes a continuous phase including an ester of the formula (I): (R2)p-Ph-(CH2)m—COO-(AO)n-R1 where R1, AO, n, m, Ph, R2 and p have defined meanings and particularly where the esters are alkyl or alkenyl benzoate esters. These esters are beneficial by having a range of viscosities, especially extending to low viscosities, and attractive toxicological and environmental profiles for use in drilling, completion and/or workover of wells.

Abstract: An electrically conductive oil mud meeting the fluid requirements for resistive logging tools and a method for preparing such mud is disclosed. The fluid has been optimized to deliver performance in a manner as similar to that of a traditional invert emulsion drilling fluid as is practical while still maintaining the required electrical conductivity for resistivity-based logging tools. This electrically conductive oil-based mud comprises a polar synthetic ester base and complimentary ester surfactants, one being more oil soluble, the other being more water soluble. The surfactants interact synergistically to provide dense packing of micelles at the palisade layer. This fluid is oil-wetting to solids, and in general behaves like a traditional oil mud.

Abstract: A method is disclosed that affords improved stability to wellbores during drilling in argillaceous formations with water-based drilling fluids. The method comprises adding to the drilling fluid a compound of the invention having the capacity in water to generate a highly efficient membrane on argillaceous materials. The compound is soluble in the drilling fluid at least at the pH at which the compound is added to the drilling fluid or exists in the drilling fluid, but is insoluble in the water in the pores of the argillaceous formations, or at least at the pH of the water in such pores.

Abstract: A method for drilling a borehole employing a drilling fluid including an additive comprising a glucose derivative with pH lowering acid, buffers and surface active agents. The drilling fluid additive preferably exhibits the following properties: activity of approximately 30%–45% in water solution; pH of about 4.5 to 5.5; a light amber to clear liquid appearance and a density of approximately 1.200 grams per cubic centimeter.

Abstract: A method for drilling, running casing in, and/or cementing a borehole in a subterranean formation without significant loss of drilling fluid is disclosed, as well as compositions for use in such method. The method employs a drilling fluid comprising a fragile gel or having fragile gel behavior and providing superior oil mud rheology and overall performance. The fluid is especially advantageous for use in deep water wells because the fluid exhibits minimal difference between downhole equivalent circulating density and surface density notwithstanding differences in drilling or penetration rates. When an ester and isomerized olefin blend is used for the base of the fluid, the fluid makes an environmentally acceptable and regulatory compliant invert emulsion drilling fluid. The fluid preferably contains no organophilic clays.

Abstract: A nutrient source for marine organisms comprising: drilling fluids containing organic contaminants; a solidification agent; a cell transport agent; and a cellulosic additive.

Abstract: Gelled organic compositions and methods for using same. The gelled compositions may be liquid organic fluids, such as gelled liquid hydrocarbons, formed from a mixture of an organic-base fluid, a carboxylic acid, and one or more metal source compounds, such as a metal salt of carboxylic acid. The gelled compositions may be used in variety of applications including, but not limited to, oil field, pipeline and processing facility applications.

Abstract: An invert emulsion drilling fluid includes an oleaginous continuous phase; a non-oleaginous discontinuous phase; a biodegradable surfactant including a di-fatty acid ester of triglycerol; and a weighting agent. It is preferred that the fatty acid have the formula RCO2H in which R is an alkyl or alkenyl having 10 to 20 carbon atoms. The oleaginous fluid is selected from diesel oil, mineral oil, synthetic oil, ester oils, glycerides of fatty acids, aliphatic esters, aliphatic ethers, aliphatic acetals, or other such hydrocarbons and combinations of these and similar compounds. The non-oleaginous phase is selected from fresh water, sea water, brine, aqueous solutions containing water soluble organic salts, water soluble alcohols or water soluble glycols or combinations of these and similar compounds.

Abstract: A drilling fluid or mud having several components, including leonardite (humic acid); potassium acetate; partially hydrolyzed polyacrylamide (PHPA); polyanionic cellulose polymer (PAC); sulfonated asphalt; sulfoalkylated tannin; polystyrene maleic anhydride copolymer; micronized cellulose fiber; calcium carbonate; and calcium carbonate. These components are preferably premixed in a dry formulation as a powder or as pellets, and shipped to the site in bags or bulk barrels. This offers substantial advantages over the prior art in that the drilling mud of the present invention may be formed simply by adding the dry mix to a predetermined amount of water, and is thus much easier to make than the prior art wet mix drilling fluids, which typically require precise ratios of several different powders and liquids to be mixed together. The humic acid serves as hydration buffer to help keep the powder or pellets dry and flowable.

Abstract: A drilling fluid or mud is described wherein the drilling fluid contains at least one alkali metal formate or monovalent carboxylic acid salt. The drilling fluid preferably further contains at least one emulsifier or surfactant and at least one hydrocarbon-based fluid. The drilling fluids of the present invention can contain other conventional ingredients. The present invention permits drilling fluids to be essentially solids free due to the use of the alkali metal formate.

Abstract: Liquid water soluble polymer suspensions in non-aqueous solvents are extremely stable over long periods of time with minimum separation of the solvent and no hard packing of the dispersed water soluble polymer. The suspensions enable a user to rapidly add the suspension to water, being mixed at low speeds, without the formation of lumps or fisheyes and without generating fugitive dust in the process. The suspensions are environmentally safe and biodegradable. Unlike many other liquid polymer suspensions, the suspensions exhibit minimal oil or grease upon dilution. They contain no surfactants that can add to the oil and grease determination. The suspensions and the fluids produced by diluting the fluids to a working concentration of the water soluble polymer exhibit low toxicity to marine organisms and to humans. The suspensions can be manufactured from ingredients suitable for use in personal care applications such as cosmetics, shampoos and the like.

Abstract: A composition for oil and gas drilling fluids containing organic contaminants comprising: a solidification agent; cell transport agent; a cellulosic additive; and wherein said composition comprises enough solidification agent to enable the solidification agent to electrolytically attract the organic contaminates to the surface of the solidification agent when hydrated.

Abstract: A process for imparting lubricity to an aqueous drilling fluid used in geological exploration involving: (a) providing an aqueous drilling fluid; (b) providing a lubricant component containing a partial glyceride of predominantly unsaturated fatty acids having from about 16 to 24 carbon atoms; and (c) introducing the partial glyceride into the aqueous drilling fluid.

Abstract: Disclosed is a hydrophilic, water soluble polymer concentrate for addition to aqueous liquids to enhance the properties thereof, particularly to increase the viscosity or decrease the fluid loss of well drilling and servicing fluids, the concentrate comprising a hydrophobic, water insoluble liquid, an organophilic clay suspension agent, the water soluble polymer, and a stabilizing agent comprising one or more acids in an amount from about 0.001% to about 1.5%, one or more anionic surfactants in an amount from about 0.001% to about 1.0%, one or more nonionic surfactants in an amount from 0.001% to about 0.625% and, from about 0% to about 0.75% of one or more water soluble organic liquids, wherein the total concentration of the stabilizing agent is from about 0.1% to about 2.5%, these percentages being based on the weight of the concentrate.

Abstract: A composition and method for treating oil and gas drilling fluids containing organic contaminants comprising: a solidification agent, and a cell transport agent; wherein the composition comprises enough solidification agent to enable the solidification agent to electrolytically attract the organic contaminates to the surface of the solidification agent when hydrated.

Abstract: A wellbore fluid having a non-aqueous continuous liquid phase that exhibits an electrical conductivity of not less than 10 &mgr;S m−1 at 1 kHz comprises a polar organic liquid (POL) which exhibits a dielectric constant of at least about 5.0 and a Hildebrand Solubility Parameter of at least about 17 (J cm−3)1/2. Oils or other organic liquids (OL) known to be suitable as the continuous liquid phase of wellbore fluids, may be used in admixture with POL component. Certain inorganic salts, organic bases, quaternary ammonium salts or hydroxides (the dissolved component, DC), display sufficient solubility (and current carrying abilities) in POL, OL or in mixtures of liquid (POL) and liquid (OL) to further improve the electrical conductivity of the mixture. The wellbore fluid can be used for providing enhanced information from electrical logging tools, measurement while drilling, logging while drilling, geosteering and the like.

Abstract: A wellbore fluid having a non-aqueous continuous liquid phase that exhibits an electrical conductivity increased by a factor in order of 104 to 107 compared to conventional invert emulsion comprises from about 0.2% to about 10% by volume of carbon black particles and one or more emulsifying surfactant(s) selected from the class including nonionic emulsifiers of Hydrophilic-Lipophilic Balance (HLB) less than about 12, and anionic surfactants wherein the counter-ion (cation) is any of alkali metal, ammonium, or hydrogen ions. This wellbore fluid can be used for drilling or completing a well and can be used for providing enhanced information from electrical logging tools, measurement while drilling, logging while drilling, geosteering and the like.

Abstract: The present invention relates to a borehole fluid comprising a lubricating compound containing at least one amphiphilic non-ionic compound obtained by reacting at least one vegetable oil or fatty acid as such or in a polymerized state on at least one amino alcohol. In one variant, the compound can be mixed with a solvent. The invention also relates to a method for verifying the lubrication power of a water-based fluid. The invention further relates to the application of said method to borehole fluids with a high pH.

Abstract: The present invention relates to a method and a fluid for drilling or intervening in a well passing through a porous, permeable formation, wherein a water-based well fluid is circulating in said well. In this method, there is added to the fluid not only the conventional ingredients for such a fluid but also a maximum of 10 wt. % of a composition obtained from a grease or oil and an alcohol, with the chain lengths of the acid and alcohol parts being chosen such that the ester thus obtained has sufficient dispersion in water, compatibility with said ingredients, does not form an emulsion with the reservoir oil, and adsorbs sufficiently on the porous formation.

Abstract: The invention relates to the use of linear and/or branched fatty alcohols containing at least 12 carbon atoms in the molecule and/or to the use of mixtures of such fatty alcohols with carboxylic acid esters as a lubricating additive in water-based drilling fluids for their use in geological exploration by drilling. The fatty-alcohol-based lubricants or lubricant systems are particularly suitable for use in water-based alkali metal silicate drilling muds which are known to be distinguished by comparatively high pH values. The additives according to the invention combine their lubricating effect with a foam-suppressing effect, i.e. prevent unwanted foaming.

Abstract: A new composition for a spotting fluid and a method of using such spotting fluid for freeing differential stuck pipe in a subterranean well drilling operation is disclosed. The composition comprises an invert water-in-oil emulsion comprising iso-butyl oleate as its external phase and glycerin as the internal phase. In an alternative embodiment, calcium chloride and water may be substituted for glycerin.

Abstract: Process for using biodegradable drilling muds, characterized in that a able surface sludge which is stable up to about 100° C., with an adjustable filtrate-reducing power of from 2 to 13 cm3 depending on the amount of filtrate-reducing agent used, and with an electrical stability of greater than or equal to 1000 volts, is introduced into the well at the start of drilling, and in that, when the temperature of the terrain passed through reaches 100° C., the surface sludge is replaced with a bottom sludge which is stable at a temperature above 200° C., the volume of the surface sludge representing from 60 to 80% by volume relative to the total volume of sludge used.

Abstract: Composition of water-based drilling fluids characterized in that they comprise an oil in water emulsion.

Abstract: A method and product is disclosed which provides emulsion stability and filtration control to invert emulsion drilling fluids. The product comprises a blend of a carboxylic acid terminated polyamide and a mixture produced by the Diels-Alder reaction of dienophiles, preferably carboxylic acids, polycarboxylic acids, acid anhydrides, or combinations or mixes thereof, with a mixture of fatty acids and resin acids. The product is extremely effective, decreasing by about two-thirds the amount of emulsifier generally required to formulate an effective drilling fluid. The product also greatly reduces and in many cases eliminates the need for conventional fluid loss additives, and additionally provides electrical stability. Moreover, the product has a pour point as low as about 20 degrees Fahrenheit with minimal solvents, thereby eliminating the need to ship large amounts of inert material for use, and may be transported in a highly active state.

Abstract: This invention provides a water-free oil based fluid polymer suspension composition for use as a rheology modifier and fluid loss reducer in oil or gas well servicing fluids. It has been found that by using white medicinal oil as a carrier, high solids content and environmental friendly anhydrous fluidized polymer suspensions of xanthan gum, cellulose ethers, guar gum and derivatives thereof can be prepared. More specifically, in one aspect, an oil-based fluid polymer suspension (FPS) composition for use in oil or gas well servicing fluids is preferred containing: a) a hydrophilic polymer, b) an organophilic clay, c) a stabilizer, and d) a white medicinal oil having selected properties.

Abstract: The use is disclosed of at least substantially water-insoluble ethers which are fluid and/or at least plastically deformable at working temperature and have flash points of at least 80° C., of mono- and/or polyfunctional alcohols of natural and/or synthetic origin or corresponding solutions of such ethers in ecologically acceptable water-insoluble oils as the dispersed oil phase of water-based O/W-emulsion drilling fluids which are suitable for the environmentally acceptable development of geological formations and which contain, if desired, insoluble, finely particulate weighting agents for the formation of water-based O/W-emulsion drilling muds and/or further additives, such as emulsifiers, fluid-loss additives, wetting agents, alkali reserves and/or auxiliary substances for the inhibition of drilled rock of high water-sensitivity.

Abstract: An invert emulsion suitable for drilling subterranean wells, in particular oil and gas wells is disclosed which has negative alkalinity and includes an oleaginous phase, and a non-oleaginous phase and an emulsifying agent which stabilizes the invert emulsion under conditions of negative alkalinity. The practice of the present invention permits the formulation of drilling fluids which are absent an alkaline reserve and are compatible with elastomers utilized in drilling equipment. Thus the invert emulsion fluids of the present invention are highly suitable for drilling oil and gas wells.

Abstract: An additive which increases the density of wellbore fluids used during the construction or repair of oil, gas, injection, water or geothermal wells comprises solid colloidal particles of weight average particle diameter (D50) of less than 2 microns, the particles being deflocculated by the action of a dispersant, preferably incorporated during the process of grinding or communication of the particles to the specified particle size. The additives may be used in any wellbore fluid such as drilling, cementing, completion, packing, work-over (repairing), stimulation, well killing and spacer fluids as well as in a dense media separating fluid or in a ship's ballast fluid.

Abstract: An invert emulsion drilling fluid includes an oleaginous continuous phase; a non-oleaginous discontinuous phase; a biodegradable surfactant including a di-fatty acid ester of triglycerol; and a weighting agent. It si preferred that the fatty acid have the formula RCO2H in which R is an alkyl or akenyl having 10 to 20 carbon atoms. The oleaginous fluid is selected from diesel oil, mineral oil, synthetic oil, ester oils, glycerides of fatty acids, aliphatic esters, aliphatic ethers, aliphatic acetals, or other such hydrocarbons and combinations of these and similar compounds. The non-oleaginous phase is selected from fresh water, sea water, brine, aqueous solutions containing water soluble organic salts, water soluble alcohols or water soluble glycols or combinations of these and similar compounds.

Abstract: Composition of water-based drilling fluids characterized in that they comprise anions with a high hydrodynamic radius.

Abstract: A new composition for a spotting fluid and a method of using such spotting fluid for freeing differential stuck pipe in a subterranean well drilling operation is disclosed. The composition comprises an invert water-in-oil emulsion comprising iso-butyl oleate as its external phase and glycerin as the internal phase. In an alternative embodiment, calcium chloride and water may be substituted for glycerin.

Abstract: A new composition for a spotting fluid and a method of using such spotting fluid for freeing differential stuck pipe in a subterranean well drilling operation is disclosed. The composition comprises an invert water-in-oil emulsion comprising iso-butyl oleate as its external phase and glycerin as the internal phase. In an alternative embodiment, calcium chloride and water may be substituted for glycerin.

Abstract: A biodegradable drilling mud, comprising a water/organic phase reverse emulsion in a volume ratio ranging from 50/50 to 10/90, which contains: a) from 1 to 5% by volume of at least one nitrogen compound selected from the group consisting of amino acids, carbamic mono- and polyamides and mono- and polycarbamic amides, of formulae (I) and (II) respectively, taken alone or as a mixture: R—[NH—CH2]n—CO—NH2  (I) R—NH—[CO—NH]m—H  (II)  wherein R is hydrogen or an alkyl group comprising from 1 to 10 carbon atoms and n and m are integers ranging from 1 to 5, b) from 2 to 10% by volume of at least one phosphorus derivative selected from the group consisting of surfactant phosphorus compounds, and c) from 2 to 10% by volume of at least one oxygenated compound selected from the group consisting of fatty acids, fatty acid esters of fatty alcohols comprising carbon-based chains comprising from 12 to 24 carbon atoms, alone or

Abstract: This Invention relates to a novel reversible thickener, i.e., a fluid whose viscosity can be carefully modulated—from very low viscosity to sufficient viscosity to act as a barrier to further flow; particularly preferred embodiments are directed to fluids and methods for stimulating hydrocarbon low viscosity to sufficient viscosity to act as a barrier to further flow; particularly preferred-bearing formations—i.e., to increase the production of oil/gas from the formation. In particular, the Present Invention is directed to a family of fluids (and methods incorporating those fluids) intended to be pumped through a wellbore and into the hydrocarbon-bearing formation.

Abstract: The invention provides a method and fluid for drilling or servicing a well in a subterranean formation containing lost circulation zones or depleted, low pressure reservoirs. The fluid comprises an aqueous liquid having dispersed therein a polymer which increases the low shear rate viscosity of the fluid to the extent that the thixotropic index of the fluid is at least about 10 and a surfactant, and wherein the fluid contains less than about 15% by volume of aphrons preferably generated by the turbulence and pressure drop as the fluid exits the drill bit in the vicinity of the formation. The method of drilling a wellbore in a subterranean formation comprises continuously circulating, while drilling, such a drilling fluid.

Abstract: An invert emulsion suitable for drilling subterranean wells, in particular oil and gas wells is disclosed which has negative alkalinity and includes an oleaginous phase, and a non-oleaginous phase and an emulsifying agent which stabilizes the invert emulsion under conditions of negative alkalinity. The practice of the present invention permits the formulation of drilling fluids which are absent an alkaline reserve and are compatible with elastomers utilized in drilling equipment. Thus the invert emulsion fluids of the present invention are highly suitable for drilling oil and gas wells.

Abstract: The invention relates to multiphase lubricant concentrates with improved properties for use in aqueous fluids for geological exploration by drilling which contain organic lubricating components which are solid and/or liquid at room temperature (O phase) together with emulsifiers finely dispersed in a continuous aqueous phase (W phase). These concentrates are characterized in that the system of O phase/W phase and emulsifiers has a phase inversion temperature (PIT) above room temperature and has been produced by heating the multiphase system to temperatures equal to or above the PIT and subsequent cooling to temperatures below the PIT. The present invention also relates to the use of the multiphase lubricant concentrates as an additive in water-based fluids for use in geological exploration by drilling and for the subsequent treatment of the resulting boreholes.

Abstract: This invention is a process for improving the rheological properties of oil well drilling fluids particularly useful for oil-based invert emulsion types of drilling fluids. The process is particularly useful when drilling in deep water from an off-shore drilling rig. The new process uses as a rheological viscosifier, for such fluids, a composition which is a mixture of organoclays and castor wax and/or castor was type rheological additives, which when added to a drilling fluid at from about 0.5 and 5% by weight, creates an inventive drilling fluid compositions less sensitive to the variety of different and varying, very hot and very cold temperatures found in the drilling hole, and in the long stem of drilling pipe. The present invention also relates to the discovery of oil based invert emulsion drilling fluids that exhibit greater efficiency and provides more stable drilling fluid viscosity and anti-settling performance over varying temperatures when compared to conventional fluids containing organoclays.

Abstract: The invention relates to the use of oil-soluble oleophilic organic liquid phases—flowable at temperatures of 0 to 10° C.—from the classes of corresponding monocarboxylic and/or polycarboxylic acid esters, carbonic acid esters, fatty alcohols and their oligoalkoxides and/or ethers as the at least predominant part of the liquid phase in storage-stable homogeneous mixtures with guar and/or water-soluble guar derivatives for their use in water-based borehole servicing fluids.

Abstract: Simplified drilling fluids (and other well bore fluids) contain a non-aqueous-base fluid and a viscosifying/fluid loss agent that meets certain performance criteria.

Abstract: An invert emulsion suitable for drilling subterranean wells, in particular oil and gas wells is disclosed which includes an oleaginous phase, and a non-oleaginous phase and a protonated amine surfactant which stabilizes the invert emulsion in the absence of an alkaline reserve material. The protonated amine surfactant has the general formula:[R--N.sup.+ --H.sub.3 ]B.sup.-wherein R is a C.sub.12 to C.sub.22 alkyl group and B.sup.- is a conjugate base of an acid; and the protonated amine surfactant is present in an amount capable of stabilizing the invert emulsion in the absence of an alkali reserve. The practice of the present invention permits the use of a broad range of esters as the oleaginous phase including simple alkyl esters which previously susceptible to hydrolysis due to the presence of an alkaline reserve material.

Abstract: The present invention relates to a method and a solution for use in downhole drilling to reduce the torque necessary to rotate the drill string. The solution comprises a phosphate and a sulfonate according to the formula (RSO.sub.3).sub.x Me.sup.x, where R is selected from the group consisting of an alkyl group, an aryl group, an alkylaryl group, and mixtures thereof having a molecular weight between about 280 and about 650, x is the number of (RSO.sub.3) groups, and Me.sup.x is a metal ion having a valence x. The phosphate is preferably a phosphate ester, ether phosphate, or soluble phosphate having a molecular weight in the range of about 300 to bout 900. The phosphate is able to operate at temperatures prevailing in drilling mud systems. The solution is pumped down a drill string as a slug in order to coat solids which accumulate in the well and allow them to be removed along with the drilling fluid.