Abstract: Biomimetic adhesive compositions can be used in various aspects of subterranean treatment operations. Methods for treating a subterranean formation can comprise: providing an adhesive composition that comprises a first polymer comprising a plurality of monomers that comprise a phenolic moiety, a biopolymer that is crosslinkable with the first polymer, a crosslinking agent, and an oxidizing agent; introducing the adhesive composition into a subterranean formation; and forming a coacervate-bound surface in the subterranean formation by crosslinking the first polymer.

Abstract: Formulation for a natural product as a replacement for the use of traditional acidic chemical stimulation methods for the emulsification, removal and release of paraffin and asphaltenes from low producing or pumped off wells and reservoirs with the use of traditional methodologies. Also a method of use of formulation for stimulating an oil well consisting of introducing into the wellbore a biodegradable, non-reactive fluid system containing a water-miscible fatty acid solvent, a solution of fatty acids, an amino alcohol, and at least one non-ionic surfactant. The fluid system may be further in the form of a nanoemulsion that is formed by combining a colloidal solution with one or more emulsifiers, an alcohol, and water. The fluid system may be used in well remediation and stimulation as well as additional, alternative applications such as the cleaning of surface and/or downhole equipment.

Abstract: This invention relates to compositions and methods of removing an organic deposit including introducing a fluid, wherein the fluid comprises at least two non-polar organic solvents and at least two polar organic solvents; allowing the fluid to dissolve at least a portion of the organic deposit; and removing at least a portion of the fluid. This invention relates to compositions and methods of removing an organic deposit including introducing a fluid, wherein the fluid comprises at least two non-polar organic solvents and at least two polar organic solvents, wherein the non-polar organic solvents comprise aromatic naphtha, terpenes, kerosene, and combination thereof, and wherein the polar solvents comprise heavy aromatic naphtha, cyclohexanone, N-2-methyl pyrrolidone, N-ethyl-2-pyrrolidone, and combination thereof, allowing the fluid to dissolve at least a portion of the organic deposit, and removing at least a portion of the fluid.

Abstract: An inhibitive water-based polymer mud system and method for using the system in drilling and in stabilizing wellbores is disclosed for use in water sensitive formations as an alternative to oil-based muds. The system comprises a fresh water or salt water base thinned or dispersed with a water soluble, biodegradable polyamide-based copolymer having at least one grafted side chain formed from ethylenic unsaturated compounds. This system is effective and has stable rheology over a broad pH range, even at a near neutral pH of 8.0. The drilling fluids do not contain heavy metals and are rheologically tolerant to contaminants such as cement, anhydrite and sodium and temperatures as high as about 400° F.

Abstract: A method of providing a substantially constant rheological profile of a drilling fluid over a temperature range of about 120° F. to about 40° F. includes adding a drilling fluid additive to the drilling fluid, wherein the drilling fluid additive includes the reaction product of a carboxylic acid with at least two carboxylic moieties; and a polyamine having an amine functionality of two or more. A composition, such as an oil based drilling fluid, includes the reaction product of a carboxylic acid with at least two carboxylic moieties and a polyamine having an amine functionality of two or more.

Abstract: This invention relates to drilling fluids and processes for making drilling fluids, such as for use in environmentally sensitive areas. The environmentally friendly drilling fluid includes a first fluid component having between about 5 weight percent to about 95 weight percent of olefins with a chain length in a range of between about C12 and about C48. The first fluid component includes at least about 50 weight percent trisubstituted olefin functionality. The environmentally friendly drilling fluid includes a second fluid component.

Abstract: A non-toxic, environmentally friendly, green flowback aid is disclosed that reduces water blockage when injected into a fractured reservoir. The composition includes an water soluble ester of a low molecular weight alcohol and a low molecular weight organic acid, an oil soluble ester of a low molecular weight alcohol and a high molecular weight fatty acid, one or more water soluble or dispersible nonionic surfactant(s) derived from vegetable or animal sources, one or more anionic or amphoteric surfactant(s) derived from animal or vegetable based sources, and, water. Compositions for low temperature applications are also disclosed that can remain fluid down to ?41° F.

Abstract: Methods of treating a wellbore comprise displacing a drilling fluid comprising an organophilic clay treated with a quaternary ammonium surfactant having an amide linkage into the wellbore. Methods of drilling a wellbore comprise: applying torque to a bit within the wellbore and concurrently applying force to urge the bit to extend through the wellbore; and circulating a drilling fluid past the bit to remove cuttings therefrom, the drilling fluid comprising an organophilic clay treated with a quaternary ammonium surfactant having an amide linkage. Methods of preparing a drilling fluid comprise: forming an organophilic clay treated with a quaternary ammonium surfactant having an amide linkage; and combining the organophilic clay with an oil-based fluid.

Abstract: A method and a device (2) for destruction of organic material in injection water for an injection well (4), in which a means (10) for introduction of water in the injection well (4), and at least one electrochemical cell (16) with associated operating means are used for in situ electrolytic generation from water of at least short-lived, free hydroxyl radicals. The distinctive characteristic of the invention is that it comprises the following steps: (A) to connect the at least one electrochemical cell (16) to the injection well (4); and (B) by means of said operating means, to conduct the injection water through said cell (16) for in situ generation of at least free hydroxyl radicals from the injection water, insofar as free hydroxyl radicals immediately destruct organic material that they engage in the injection water.

Abstract: Methods are provided including methods of treating a well bore with drilling fluids comprising organophilic clays treated with quaternary ammonium surfactants having at least two amide linkages. In some embodiments, the methods comprise: providing a drilling fluid comprising a nonaqueous phase and an organophilic clay treated with a quaternary ammonium surfactant having at least two amide linkages; and placing at least a portion of the drilling fluid into the well bore. In other embodiments, the methods comprise combining an organophilic clay with a quaternary ammonium surfactant having at least one amide linkage to form a mixture, and combining the mixture with a fluid comprising a nonaqueous phase to form a drilling fluid. Additional methods are also provided.

Abstract: The present invention provides an internal olefin composition comprising a mixture of 60 to 80% by mass of an olefin having 16 carbon atoms and 40 to 20% by mass of an olefin having 18 carbon atoms wherein a content of an ?-olefin in the mixture is 10% by mass or less, and a content of a branched olefin in the mixture is 10% by mass or less, which has a good biodegradability even when discharged into the environments, a less toxicity against marine organisms, etc., and a sufficient fluidity when used as a base oil for oil drilling, etc.

Abstract: The invention relates to a borehole treatment composition containing an aqueous phase and a non-aqueous oil phase, emulsifiers and, where appropriate, further customary additives, the non-aqueous oil phase containing at least one of a) paraffins having from 5 to 22 carbon atoms; and b) internal olefins having from 12 to 30 carbon atoms in the molecule; in the form of a blend with c) carboxylic esters of the formula R—COO—R?, where R stands for a linear or branched, saturated or unsaturated alkyl radical having from 15 to 25 carbon atoms and R? denotes a saturated, linear or branched alkyl radical having from 3 to 22 carbon atoms. The ratio of the toxicity of internal olefins of chain length C16/C18 (standard IO) to the toxicity of the constituents of the non-aqueous oil phase, in each case measured by the Leptocheirus plumulosus acute, static 96 hour/10 day sediment toxicity test (in accordance with ASTM E 1367-92 & EPA/600/R-94/025, Section 11), is less than 1.

Abstract: Fluid producing or injecting wells may be treated with a water-in-oil emulsion for the removal or inhibition of unwanted particulates, including pipe dope, asphaltenes and paraffins. In addition, such emulsions are effective in the displacement of oil base drilling muds and/or residues from such muds from wells. The emulsion may also be used to break the interfacial and/or rheological properties of oil base mud and synthetic oil base mud filter cakes, and act as a demulsifier to break the water-in-oil emulsion present in such oil base and synthetic oil base muds. The water-in-oil emulsions may optionally contain a dispersing agent as well as a surfactant.

Abstract: A biodegradable water-in-synthetic oil base emulsion, effective in the removal of filter cakes, consists of an external phase of a surfactant emulsified in a paraffinic base oil. The emulsion is particularly effective in breaking-down the interfacial rheological properties of oil base mud and synthetic oil base mud filter cakes and acts as a demulsifier to break the water-in-oil emulsions present in such oil base and synthetic oil base muds.

Abstract: A method of treating a well consists of introducing into the wellbore a biodegradable fluid system containing a fatty acid ester, such as methyl soyate. The fluid system may further contain a lactic acid ester, such as ethyl lactate, and/or a nonionic surfactant. The fluid system may be used in displacement, well remediation and stimulation as well as additional, alternative applications such as the cleaning of surface and/or downhole equipment.

Abstract: A high-temperature lubricant is shown and described. The lubricant includes a base stock and about 1 to about 20 weight percent zirconium 2-ethylhexanoate. The lubricant may also include about 1 to about 9 weight percent bismuth 2-ethylhexanoate.

Abstract: A method of treating a well consists of introducing into the wellbore a biodegradable fluid system containing a blend of lactic acid ester, such as ethyl lactate, and a fatty acid ester, such as methyl soyate. The fluid system may be further in the form of a microemulsion that is formed by combining a blend with one or more emulsifiers, an alcohol, and water. The fluid system may be used in displacement, well remediation and stimulation as well as additional, alternative applications such as the cleaning of surface and/or downhole equipment.

Abstract: The invention concerns a biodegradable lubricating composition, based on mineral hydrocarbon oil and ester, comprising a majority amount of a mineral hydrocarbon fraction substantially free of aromatic compounds, said fraction having a normal paraffin content not more than 10 wt. % and an isoparaffin content not less than 36 wt. %, and a minority amount ranging between 5 and 40 wt. % of at least a fatty acid ester.

Abstract: A water-base drilling fluid for use in drilling wells through a formation containing a shale which swells in the presence of water. The drilling fluid preferably includes: an aqueous based continuous phase, a weight material, and a shale hydration inhibition agent having the formula: H2N—R—{OR?}x—Y.[H+B?]d in which R and R? are alkylene groups having 1 to 6 carbon atom and x is a value from about 1 to about 25. The Y group should be an amine or alkoxy group, preferably a primary amine or a methoxy group. The acid H+B? is a protic acid selected from the group consisting of inorganic acids and organic acids, illustrative examples of which include: hydrochloric, hydrobromic, sulfuric, phosphoric, nitric, boric, perchloric, formic, acetic, halogenated acetic, propionic, butyric, maleic, fumeric, glycolic, lactic, citric and combinations of these. The shale hydration inhibition agent should be present in sufficient concentration to reduce the swelling of the shale.

Abstract: The present invention provides methods and compositions for treating subterranean zones penetrated by well bores utilizing environmentally safe viscous fluids. A method of the invention comprises the following steps. A viscous treating fluid composition is provided comprised of water, a viscosity increasing polymer and a water soluble delayed polymer breaker that comprises a mixture of sodium perborate tetrahydrate and a solubility increasing boron complex or ester forming compound. The viscous treating fluid composition is introduced into the subterranean zone wherein the viscous treating fluid is allowed to break into a thin fluid of reduced viscosity.

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: Blends of synthetic olefins for use as the continuous phase of fluids selected from the group consisting of drilling, drill-in, and completion fluids. The blends meet EPA discharge requirements while also permitting investigators to clearly discern the presence and quantity of biological markers in reservoir fluid samples—particularly pristane and phytane.

Abstract: A water-base drilling fluid for use in drilling wells through a formation containing a shale which swells in the presence of water. The drilling fluid preferably includes: an aqueous based continuous phase, a weight material, and a shale hydration inhibition agent having the formula: H2N—R—{OR′}x—Y in which R and R′ are alkylene groups having 1 to 6 carbon atoms and x is a value from about 1 to about 25. The Y group should be an amine or alkoxy group, preferably a primary amine or a methoxy group. The shale hydration inhibition agent should be present in sufficient concentration to reduce the swelling of the shale. Also inclusive of the present invention is a method of reducing the swelling of shale clay encountered during the drilling of a subterranean well, the method comprising circulating in the well a water-base drilling fluid formulated in accordance with the present invention.

Abstract: The invention provides a method of taking a crustal core sample, wherein the crustal core sample is obtained in a state coated with antimicrobial polymeric gel obtained by polymerizing an antimicrobial monomer. It is preferred that antimicrobial monomer is a quaternary ammonium salt compound, and the polymer contains a component derived from the antimicrobial monomer in a proportion of 1 to 10 mol %.

Abstract: Discloses environmentally friendly, low temperature base oils and drilling fluids. The drilling fluid is constituted of one or more of weighting agents, emulsifiers, wetting agents, viscosifiers, fluid loss control agents, proppants, and other particulates such as used in a gravel pack, emulsified with a paraffinic solvent composition which forms a continuous oil phase, or water-in-oil invert phase. The solvent composition is constituted of a mixture of C10-C24 n-paraffins and isoparaffins having an isoparaffin:n-paraffin molar ratio ranging from about 0.5:1 to about 9:1, the isoparaffins of the mixture contain greater than 30 percent, preferably from about 30 percent to about 50 percent, of mono-methyl species, and greater than 30 percent, preferably from about 30 percent to about 50 percent of multi-methyl branched species and isoparaffins which contain one or more branches of carbon number higher than methyl, based on the total weight of the isoparaffins in the mixture.

Abstract: A method is disclosed that provides a stable invert emulsion for an oil-based drilling fluid with an environmentally friendly additive that effectively eliminates shale hydration and consequent borehole erosion. The additive is preferably potassium formate, although other formates or acetates may be substituted. In the method, the potassium formate is dissolved in the water phase of the emulsion in lieu of other less environmentally friendly salts such as sodium chloride. The water activity of the emulsion and of the formation being drilled is monitored during drilling so that additional formate may be added as needed to maintain such water activities in balance. That is, preferably, the water activity of the potassium formate will be the same as or less than the water activity of the formation.

Abstract: A water-base fluid for use in drilling wells and other drilling operation includes a shale which swells in the presence of water.

Abstract: Improved methods of cementing in subterranean zones penetrated by well bores are provided. The methods are basically comprised of the steps of preparing a cement composition comprised of a hydraulic cement, a biodegradable, substantially non-dispersing set retarder of low anionic character comprised of polysuccinimide and sufficient water to form a slurry, placing said cement composition in said subterranean zone and allowing said cement composition to set into a solid mass therein.

Abstract: Disclosed are compositions having utility as well fluid base oils. The base oils are comprised of a mixture of internal predominantly linear tetradecene (C14) isomers and internal predominantly linear hexadecene (C16) isomers. The base oils of this invention have pour point temperatures lower than −25° C. and are environmentally acceptable to marine life. The base oils disclosed are ideal candidates for use in cold climates and for offshore drilling.

Abstract: A non-toxic, inexpensive synthetic fluid for use in wellbore fluids (e.g., drilling fluids) is selected from the group consisting of (A) fluids having (I) a pour point greater than about −30° C. (−22° F.) and (II) a cetane index greater than 50, and comprising (i) at least about 95 weight percent hydrocarbons containing 11 or more carbon atoms, (ii) greater than 5 weight percent hydrocarbons containing 18 or more carbon atoms, (iii) at least about 50 weight percent isoparaffins, (iv) at least about 90 weight percent total paraffins, (v) about 1 or less weight percent naphthenics, (vi) less than 0.1 volume percent aromatics, and (vii) at least 2 hydrocarbons containing a consecutive number of carbon atoms, and (B) fluids comprising (i) at least about 95 weight percent hydrocarbons containing 10 or more carbon atoms and (ii) at least about 90 weight percent n-paraffins.

Abstract: A water-base drilling fluid for use in drilling wells through a formation containing a shale which swells in the presence of water. The drilling fluid preferably includes: an aqueous based continuous phase, a weight material, and a shale hydration inhibition agent having the formula: H2N—CH(CH3)CH2{—OCH2CH(CH3)—}x—NH2 in which x is a value less than 15. The shale hydration inhibition agent should be present in sufficient concentration to reduce the swelling of the shale. Preferably x has an average number between about 1 and about 5 and more preferably x has an average number of about 2.6. Also inclusive of the present invention is a method of reducing the swelling of shale clay encountered during the drilling of a subterranean well, the method comprising circulating in the well a water-base drilling fluid formulated in accordance with the present invention.

Abstract: A non-toxic, inexpensive synthetic fluid for use in wellbore fluids (e.g., drilling fluids) is selected from the group consisting of (A) fluids having (I) a pour point greater than about -30.degree. C. (-22.degree. F.) and (II) a cetane index greater than 50, and comprising (i) at least about 95 weight percent hydrocarbons containing 11 or more carbon atoms, (ii) greater than 5 weight percent hydrocarbons containing 18 or more carbon atoms, (iii) at least about 50 weight percent isoparaffins, (iv) at least about 90 weight percent total paraffins, (v) about 1 or less weight percent naphthenics, (vi) less than 0.1 volume percent aromatics, and (vii) at least 2 hydrocarbons containing a consecutive number of carbon atoms, and (B) fluids comprising (i) at least about 95 weight percent hydrocarbons containing 10 or more carbon atoms and (ii) at least about 90 weight percent n-paraffins.

Abstract: A non-toxic, inexpensive synthetic fluid for use in wellbore fluids (e.g., drilling fluids) is selected from the group consisting of (A) fluids having (I) a pour point greater than about -30.degree. C. (-22.degree. F.) and (II) a cetane index greater than 50, and comprising (i) at least about 95 weight percent hydrocarbons containing 11 or more carbon atoms, (ii) greater than 5 weight percent hydrocarbons containing 18 or more carbon atoms, (iii) at least about 50 weight percent isoparaffins, (iv) at least about 90 weight percent total paraffins, (v) about 1 or less weight percent naphthenics, (vi) less than 0.1 volume percent aromatics, and (vii) at least 2 hydrocarbons containing a consecutive number of carbon atoms, and (B) fluids comprising (i) at least about 95 weight percent hydrocarbons containing 10 or more carbon atoms and (ii) at least about 90 weight percent n-paraffins.

Abstract: A non-toxic, inexpensive synthetic fluid for use in wellbore fluids (e.g., drilling fluids) is selected from the group consisting of (A) fluids having (I) a pour point greater than about -30.degree. C. (-22.degree. F.) and (II) a cetane index greater than 50, and comprising (i) at least about 95 weight percent hydrocarbons containing 11 or more carbon atoms, (ii) greater than 5 weight percent hydrocarbons containing 18 or more carbon atoms, (iii) at least about 50 weight percent isoparaffins, (iv) at least about 90 weight percent total paraffins, (v) about 1 or less weight percent naphthenics, (vi) less than 0.

Abstract: The present invention relates to synthetic hydrocarbon as the continuous phase of a drilling fluid. These hydrocarbons comprise mostly linear olefins, preferably C.sub.14 to C.sub.18 olefins.

Abstract: A fluid selected form the group consisting of a drilling, a drill-in, and a completion fluid, said fluid comprising a substantially linear heteropolyglycol in an amount effective to perform a function selected from the group consisting of polymer stabilization, shale stabilization, and a combination thereof. The fluid preferably comprises water as a continuous phase, and the heteropolyglycol preferably consists essentially of monomers selected from the group consisting of ethylene oxide and linear alpha-omega alkylene diols.

Abstract: A non-toxic, inexpensive synthetic fluid for use in wellbore fluids (e.g., drilling fluids) is selected from the group consisting of (A) fluids having (I) a pour point greater than about -30.degree. C. (-22.degree. F.) and (II) a cetane index greater than 50, and comprising (i) at least about 95 weight percent hydrocarbons containing 11 or more carbon atoms, (ii) greater than 5 weight percent hydrocarbons containing 18 or more carbon atoms, (iii) at least about 50 weight percent isoparaffins, (iv) at least about 90 weight percent total paraffins, (v) about 1 or less weight percent naphthenics, (vi) less than 0.1 volume percent aromatics, and (vii) at least 2 hydrocarbons containing a consecutive number of carbon atoms, and (B) fluids comprising (i) at least about 95 weight percent hydrocarbons containing 10 or more carbon atoms and (ii) at least about 90 weight percent n-paraffins.

Abstract: A tracer solution suitable for use in measuring flow velocities in a borehole, includes: a) a gadolinium salt of a carboxylic acid of general formula ##STR1## where R is an alkyl of not less than four carbon atoms, typically C4 or C5 alkyl, and R.sub.1 and R.sub.2 are hydrogen or an alkyl group, typically hydrogen, methyl or ethyl; b) a free branched-chain carboxylic acid such as an excess of the acid used to form the Gd salt; and c) a non-polar solvent such as hexane or heptane. The Gd content of the solution should be not less than about 50 g/l and is best when it is as high as possible, for example greater than 100 g/l, and the viscosity should be less than 20 cP.

Abstract: A non-toxic, inexpensive synthetic fluid for use in wellbore fluids (e.g., drilling fluids) is selected from the group consisting of (A) fluids having (I) a pour point greater than about -30.degree. C. (-22.degree. F.) and (II) a cetane index greater than 50, and comprising (i) at least about 95 weight percent hydrocarbons containing 11 or more carbon atoms, (ii) greater than 5 weight percent hydrocarbons containing 18 or more carbon atoms, (iii) at least about 50 weight percent isoparaffins, (iv) at least about 90 weight percent total paraffins, (v) about 1 or less weight percent naphthenics, (vi) less than 0.1 volume percent aromatics, and (vii) at least 2 hydrocarbons containing a consecutive number of carbon atoms, and (B) fluids comprising (i) at least about 95 weight percent hydrocarbons containing 10 or more carbon atoms and (ii) at least about 90 weight percent n-paraffins.

Abstract: A drilling fluid additive for use during drilling and excavating applications, the additive comprises a mixture of an oil, an ester alcohol, nonionic surfactant and polypropylene glycol; and a method for manufacturing a drilling fluid additive comprising the step of admixing an oil, an ester alcohol, a nonionic surfactant, and a polypropylene glycol.

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: The invention relates to the use of at least predominantly linear hydrocarbon compounds olefinically unsaturated in the alpha-position with flashpoints of at least about 80.degree. as the oil phase or as part of the oil phase of oil- or water-based free-flowing borehole servicing preparations. Particular significance is attributed to corresponding drilling fluids which, together with the alpha-olefins, contain other oil phases from the field of borehole servicing preparations and are distinguished by ecological compatibility, being degradable under both aerobic and anaerobic conditions. Suitable mixture components for the oil phase are, in particular, oleophilic alcohols, ethers and corresponding esters selected from carboxylic acid esters and/or carbonic acid esters.

Abstract: The present invention provides drilling fluid additives for water-based drilling muds comprising olefins having the following general structure:C.sub.n H.sub.2?(n-x)+1!wherein n is between about 8-30; x is the number of carbon-carbon double bonds in said olefins; x is between about 1-n/2; and, said olefins comprise between about 0-6 substituents selected from the group consisting of alkyl and alkenyl groups having between about 1-5 carbon atoms. The additives may be used as lubricants, rate of penetration enhancers, and/or spotting fluids for water-based drilling muds.

Abstract: The invention concerns wellbore fluids suitable for use in the oil and gas exploration and production industries and embraces fluids used for drilling, completion, workover or packing of wellbores. The invention is especially concerned with biodegradable wellbore fluids the liquid phase of which consists of an oil, or of water-in-oil "invert" emulsions, where the oil phase comprises n-alkanes.

Abstract: The present invention provides non-toxic, biodegradable purified paraffins which may be used as lubricants, rate of penetration enhancers, and/or spotting fluids for water-based drilling muds. When used as a spotting fluid additive, the paraffin isomers preferably are supplemented with functional additives, namely emulsifiers, viscosifiers, surfactants, and/or brine. When used as lubricants and/or rate of penetration enhancers, the paraffin isomers preferably are used alone or in combination with surfactants.

Abstract: Acetals are used as a mineral oil substitute, oil component or base oil in invert-emulsion drilling muds, emulsion drilling muds, engine oils, gearbox oils, lubricating oils and also metal-working fluids, coolants, cooling lubricants and hydraulic fluids. As compared with conventional mineral oils, acetals show good biodegradability and are less toxic.

Abstract: The present invention relates to synthetic hydrocarbons produced by skeletal isomerization, and the isomerization process. The products are especially useful as the continuous phase of a drilling fluid, for example when prepared from C.sub.14 to C.sub.18 linear alpha-olefins via isomerization or hydroisomerization, and as lube oils. The present invention also relates to a process for producing synthetic hydrocarbons by skeletally isomerizing C.sub.12+ olefins over a catalyst comprising an intermediate pore size molecular sieve, with or without Group VIII metals under skeletal isomerization conditions which result in little, preferably in substantially no, olefin cracking or oligomerization.

Abstract: The present invention relates to synthetic hydrocarbon as the continuous phase of a drilling fluid. These hydrocarbons comprise mostly linear olefins, preferably C.sub.14 to C.sub.18 olefins.

Abstract: An environmentally friendly invert drilling fluid comprises a water-in-oil emulsion which includes (a) at least 50 volume percent of a low toxicity base oil, and (b) at least one additive selected from the group consisting of emulsifiers, viscosifiers, weighing agents, oil wetting agents and fluid loss preventing agents, at least about 25 weight percent of the base oil content of the drilling fluid being a mixture of a linear alkane combined with a branched chain alkane, the alkanes individually having from about 14 to about 30 carbon atoms.

Abstract: A water based drilling fluid comprises 1-8% of an additive comprising saturated terpene, a mixture of saturated terpenes or a mixture of saturated and unsaturated terpenes. The drilling fluid is substantially non-toxic and has an LC-50 greater than 30,000 ppm and preferably greater than 100,000 ppm. The most economic additives are a mixture of saturated and unsaturated terpenes and have at least 30% saturated terpenes. The drilling fluid has the advantage of low toxicity over unsaturated terpene drilling fluids.