Abstract: An electropositive and water-based production well treating fluid system exhibits electropositivity by using a cationic viscosifier meanwhile matched with a cationic fluid loss additive and, optionally, contains a mud-building agent, an electrical stabilizing agent, a colloid-stabilizing agent, lubricant, an oil layer protective agent and/or a weighting agent. The electropositive production well treating fluid can beffer solve the contradiction of technical requirements between “treating fluid stability” and “bore hole stability”, and features a strong ability to inhibit the dispersion of clay, a good effect of protecting oil-gas reservoirs, fast drilling speeds, regular shape of bore holes and good resistance to salt.

Abstract: The present invention relates to methods and compositions for use in subterranean operations. More particularly, the present invention relates to additives comprising one or more silicates used to treat tar resident in a well bore, and methods of use. In one embodiment, the present invention provides a method of treating tar resident in a well bore comprising providing a tar-treating additive comprising one or more silicates introducing the tar-treating additive into the well bore; and allowing the tar-treating additive to react with the tar resident in the well bore so as to at least partially reduce the adhesiveness of the tar.

Abstract: A method and drilling fluid additive composition are provided for reducing lost circulation and seepage loss when synthetic or oil based drilling fluid is used. The method includes injecting drilling fluid and 1 to 50 pounds per barrel of a loss control additive having a composition comprising 20 to 80 parts by weight fibrous particles, 10 to 40 parts by weight lignite, and 10 to 40 parts by weight phenol-formaldehyde resin.

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: Fluids, such as completion fluids, containing at least one alkali metal tungstate and optionally at least one chelating agent are described. Methods of removing a filter cake from a well bore surface, which may include one or more alkaline earth metal sulfates, is also described, wherein the method includes contacting the filter cake with the completion fluid of the present invention. A drilling fluid or mud is also described wherein the drilling fluid contains at least one alkali metal tungstate. The drilling fluid preferably further contains at least one emulsifier or surfactant and at least one hydrocarbon-based fluid. The various fluids of the present invention can contain other conventional ingredients and optionally at least one alkali metal formate. The present invention permits the fluids to be essentially solids free due to the use of the alkali metal tungstate.

Abstract: The present invention relates to settable compositions that comprise magnesium oxide and at least one divalent salt and associated methods of use. In some embodiments, the present invention discloses methods of a forming a hardened mass comprising providing a settable composition comprising magnesium oxide, and a brine comprising water and a divalent salt; placing the settable composition into a desired location; and allowing the settable composition to set to form the hardened mass. In other embodiments, the present invention discloses methods of forming a hardened mass in a subterranean formation comprising placing a brine comprising water and a divalent salt into the subterranean formation; contacting the brine with magnesium oxide; and allowing the brine and the magnesium oxide to react to form the hardened mass. In other embodiments, the present invention discloses methods forming a casing in a well bore, and converting a drilling fluid to a settable composition.

Abstract: Provided are methods comprising providing an aqueous polymer dispersion comprising water, an anionic salt, a water-based friction reducing polymer, a polyol, an anionic surfactant, and a nonionic surfactant; mixing the aqueous polymer dispersion with additional water to form an aqueous treatment fluid; and introducing the aqueous treatment fluid into a subterranean formation. Also provided are methods comprising providing an aqueous treatment fluid comprising water, an anionic salt, a water-based friction reducing polymer in an amount sufficient to provide friction reduction without forming a gel, a polyol, an anionic surfactant, and a nonionic surfactant; and introducing the aqueous treatment fluid into a subterranean formation.

Abstract: A circulation loss combination for water-based drilling fluid system(s) comprising: a first amount of alkali metal silicate; a second amount of water insoluble particulate; and, a quantity of water soluble activating agent effective to reduce the pH of the water-based drilling fluid system to a value sufficiently low to form an effective circulation loss structure at a desired period of time after addition to the water-based drilling fluid system.

Abstract: An additive that increases the density of fluids containing a sized barite weighting agent. The wellbore fluid has rheological properties comparable to a conventional wellbore fluids but does not exhibit problems with sag and resulting variations in density. An illustrative embodiment is directed to a method for making the sized barite weighting agent and a method for using such sized barite weighting agent in a wellbore fluid. In one preferred embodiment the sized barite weighting agent has a particle diameter between 4 ?m to 15 ?m In another preferred embodiment, the additive has a D50 (by weight) of approximately 1 ?m to 6 ?m. In another preferred embodiment the additive has a D90 (by weight) of approximately 4 ?m to 8 ?m. The additive may be used in any wellbore fluid such as drilling, cementing, completion, packing, work-over (repairing), stimulation, well killing, and spacer fluid.

Abstract: The invention provides well drilling and servicing fluids, and methods of drilling, completing, or working over a well therewith, preferred fluids comprise an aqueous liquid, a water soluble polymer viscosifier (preferably xanthan gum), a polymeric fluid loss control additive (preferably a partially depolymerized partially crosslinked hydroxyalkyl ether derivative of starch or a hydroxyalkyl ether derivative of a partially crosslinked and partially depolymerized starch), a bridging agent comprising a particulate calcined magnesia that has an Activity Index greater than about 800 seconds, and an additive selected from the group consisting of citric acid, alkali metal salts of citric acid, ammonium citrate, and mixtures thereof in an amount sufficient to increase the low shear rate viscosity of the fluids, preferably from about 0.05–5 ppb, most preferably from about 0.15–3 ppb.

Abstract: The invention provides well drilling and servicing fluids, and methods of drilling, completing, or working over a well therewith, preferred fluids comprise an aqueous liquid, a water soluble polymer viscosifier (preferably xanthan gum), a polymeric fluid loss control additive (preferably a partially depolymerized partially crosslinked hydroxyalkyl ether derivative of starch or a hydroxyalkyl ether derivative of a partially crosslinked and partially depolymerized starch), a bridging agent comprising a particulate calcined magnesia that has an Activity Index greater than about 800 seconds, and citric acid in an amount sufficient to increase the low shear rate viscosity of the fluids. The invention further provides a method of increasing the low shear rate viscosity of fluids which contain a water soluble polymer and a calcined magnesia bridging agent which has an Activity Index greater than about 800 seconds.

Abstract: Settable drilling fluids comprising an aqueous-based drilling fluid and cement kiln dust. Methods of cementing in a subterranean formation comprising: providing a settable drilling fluid comprising an aqueous-based drilling fluid and cement kiln dust, introducing the settable drilling fluid into a subterranean formation, and allowing the settable drilling fluid to set in the subterranean formation. Methods of converting an aqueous-based drilling fluid to a settable drilling fluid comprising: providing the aqueous-based drilling fluid, and adding cement kiln dust to the aqueous-based drilling fluid to form the settable drilling fluid. Methods of drilling a well bore and cementing a well bore comprising: drilling a well bore, circulating an aqueous-based drilling fluid in the well bore during the step of drilling the well bore, adding cement kiln dust to the aqueous-based drilling fluid to form a settable drilling fluid, and allowing the settable drilling fluid to set in the well bore.

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: Improved well fluids that include hollow particles, and methods of using such improved well fluids in subterranean cementing operations are provided. Also provided are methods of cementing, methods of reducing annular pressure, and well fluid compositions. While the compositions and methods of the present invention are useful in a variety of subterranean applications, they may be particularly useful in deepwater offshore cementing operations.

Abstract: An additive that increases the density of fluids containing a sized barite weighting agent. The wellbore fluid has rheological properties comparable to a conventional wellbore fluids but does not exhibit problems with sag and resulting variations in density. An illustrative embodiment is directed to a method for making the sized barite weighting agent and a method for using such sized barite weighting agent in a wellbore fluid. In one preferred embodiment the sized barite weighting agent has a particle diameter between 4 ?m to 15 ?m In another preferred embodiment, the additive has a D50 (by weight) of approximately 1 ?m to 6 ?m. In another preferred embodiment the additive has a D90 (by weight) of approximately 4 ?m to 8 ?m. The additive may be used in any wellbore fluid such as drilling, cementing, completion, packing, work-over (repairing), stimulation, well killing, and spacer fluid.

Abstract: An additive that increases the density of fluids containing a sized barite weighting agent. The wellbore fluid has rheological properties comparable to a conventional wellbore fluids but does not exhibit problems with sag and resulting variations in density. An illustrative embodiment is directed to a method for making the sized barite weighting agent and a method for using such sized barite weighting agent in a wellbore fluid. In one preferred embodiment the sized barite weighting agent has a particle diameter between 4 ?m to 15 ?m In another preferred embodiment, the additive has a D50 (by weight) of approximately 1 ?m to 6 ?m. In another preferred embodiment the additive has a D90 (by weight) of approximately 4 ?m to 8 ?m. The additive may be used in any wellbore fluid such as drilling, cementing, completion, packing, work-over (repairing), stimulation, well killing, and spacer fluid.

Abstract: Methods and compositions for wellbore treating fluids, especially drilling fluids, that comprise zeolite and a carrier fluid.

Abstract: The invention discloses methods of formulating an alkali metal silicate-containing drilling fluid and drilling a well therewith. Thus an alkali metal silicate is added to an aqueous base drilling fluid, when the drilling fluid is being circulated while drilling, at a rate sufficient to react with the drilled cuttings and freshly exposed surface of the borehole while leaving very little excess soluble silicate in the drilling fluid circulated to the surface. The rate of addition of the silicate is based on the circulation rate of the drilling fluid in the wellbore and the volume of the hole being drilled.

Abstract: The present invention provides variable density fluid compositions and methods for using such compositions in a subterranean formation. One exemplary embodiment of the variable density fluid compositions of the present invention comprises a variable density fluid comprising: a base fluid, and a portion of variable pressure weighting material particles.

Abstract: A process to substantially reduce fluid loss in which an appropriate amount of a non-flowing gel of sufficient strength is emplaced to substantially eliminate or reduce loss of the drilling fluid. The gel composition of the process includes: (1) a non-cellulose containing copolymer having vinyl phosphonate co-monomer units which may be incorporated into the polymer by copolymerization with the other co-monomer(s) comprising the polymer or by grafting upon an already existing polymer or co-polymer, (2) a crosslinking agent active upon the phosphonate groups, (3) a crosslinking initiator comprising a Bronsted Lowry base or Lewis base and (4) an aqueous solvent.

Abstract: A method of improving the lubricity of an aqueous based drilling fluid composed of an aqueous base fluid, and a weighting agent. The method involves the addition of an effective amount of a phospholipid to substantially reduce the coefficient of friction when compared to the fluid absent the phospholipids. Preferably the phospholipids have the structure: in which R and R? are C6 to C25 hydrocarbon groups; and A is an anion to counter the cationic charge.

Abstract: The present invention provides compositions of treating subterranean zones penetrated by well bores in primary well cementing operations, well completion operations, production stimulation treatments and the like. The invention includes aqueous well treating fluids comprised of water and a water soluble polymer complex fluid loss control additive. Preferred polymer complexes comprise water-soluble polymers made in the presence of hydroxyethylcellulose.

Abstract: Drilling fluid systems, graphite particle mixtures, and methods for use thereof including: (a) drilling fluid systems having effective rheology and lubricity properties comprising a suspension of graphite particles having a particle size distribution sufficient to permit greater than 65 wt. % of the graphite particles to pass through a shaker screen having a mesh size of about 80 or less; and (b) spotting fluids having effective rheology comprising graphite particles having an average particle size of 120 mesh or greater.

Abstract: A method of formulating and the resulting biodegradable wellbore fluid includes a first synthetic internal olefin fraction having from 16 to 18 carbon atoms (C16-18 IO), a second synthetic internal olefin fraction having between 15 to 18 carbon atoms (C15-18 IO), and a third synthetic internal olefin fraction having 15 to 16 carbon atoms (C15-16 IO). The components of the wellbore fluid are blended such that the desired characteristics of polycyclic aromatic hydrocarbon content, toxicity and biodegrability are balance to achieve compliance with environmental requirements for hydrocarbon based drilling fluids.

Abstract: A drilling fluid additive is provided wherein the additive is manufactured by a method comprised of admixing graphite with at least one carrier such as a polypropylene glycol or oil to create a suspended mixture, and allowing the surface of the graphite to be pre-wet with the carrier prior to adding the mixture to a drilling fluid.

Abstract: A drilling fluid additive system is provided wherein the system comprises: a drilling fluid additive comprising talc, graphite and at least one carrier such as a glycol; and hydrophilic clay, a pH controller, a fluid loss controller, and at least one dispersant.

Abstract: A drilling fluid additive system is provided wherein the system is manufactured by a method comprised of admixing graphite with at least one carrier such as a polypropylene glycol or oil to create a suspended mixture, and allowing the surface of the graphite to be pre-wet with the carrier prior to adding the mixture to a drilling fluid; and then further admixing hydrophilic clay, a pH controller, a fluid loss controller, and at least one dispersant to said drilling fluid additive system.

Abstract: Methods and compositions relating to fluid loss control operations are provided. Examples of compositions may comprise ceramic particulate bridging agents and improved fluid loss control additives, and methods of using those compositions to provide fluid loss control. An embodiment of a method of providing fluid loss control from a first location to a second location may comprise the steps of: providing a treatment fluid comprising ceramic particulate bridging agents, a modified starch composition, and a base fluid; introducing the treatment fluid to the first location; and allowing the treatment fluid to form a filter cake to prevent fluid loss from the first location to the second location.

Abstract: The present invention provides the use of surface-modified nanoparticles in fluids used to recover hydrocarbon from underground formations. The use of surface-modified nanoparticles in such fluids provides foams that are stable under pressure yet have a shorter foam lifetime than typical surfactant-stabilized foams after the pressure is released or lowered.

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/or a wetting agent with a reaction product or 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 of the invention is extremely effective, decreasing by about two-thirds the amount of emulsifier generally required to formulate an effective drilling fluid. The product of the invention also greatly reduces and in many cases eliminates the need for conventional fluid loss additives, and additionally provides electrical stability.

Abstract: A lubricant for use in silicic acid muds and other drilling fluids comprising silicate or silica species is disclosed. The lubricant significantly improves the lubricity of the fluid. A method of drilling a wellbore in a subterranean formation employing the lubricant is also disclosed. A preferred lubricant of the invention comprises about 80 volume percent 2-octyldodecanol and about 20 volume percent alkylglucoside. The alkylglucoside is preferably comprised of 2-ethylhexylglucoside or a mixture of alkylglucosides having more than about 10 carbon atoms in the alkyl chain.

Abstract: Methods of cementing in a subterranean formation include passing a swelling agent to a permeable zone in a subterranean formation. The swelling agent is combined with a carrier fluid before being passed to the permeable zone. Upon contacting an aqueous fluid, the swelling agent swells in the permeable zone. The aqueous fluid may already be present in the subterranean formation, or alternatively, it may be introduced to the subterranean formation after passing the swelling agent into the subterranean formation. The swelling agent substantially inhibits a cement slurry subsequently pumped into the subterranean formation from passing through the permeable zone. The cement slurry therefore continues flowing down through the casing and up through the annulus where it sets and forms a strong cement column.

Abstract: A method of making a rheology modified aqueous composition, particularly useful for drilling, milling and mining applications, is disclosed. The method includes admixing, with a clay and water, a material or materials whose constituents substantially conform to the proportions of the empirical formula M?mM?n(OH)(2m+3n+qa+br)(Aq)a(Br)b.xH2O, where M? is a divalent metal cation, M? is a trivalent metal cation, A and B are anions, and a, b, m, n, q, r, and x are defined herein. Calcined hydrotalcite and hydrotalcite-like materials are particularly preferred as starting materials. Optionally, an aluminum oxide, a nitrogen-containing compound, or both may be added. The resulting composition is preferably an elastic solid exhibiting stress-dependent fluidity, desirable temperature resistance, lubricity, inhibition of reactivity, relatively low cost, and pressure resistance. A dry composition and method of making are also disclosed.

Abstract: The present invention relates to subterranean operations, and more particularly, to settable fluids comprising vitrified shale and hydrated lime and methods of using such settable fluids in subterranean applications. In an exemplary embodiment, the settable fluids of the present invention may be used as a displacement fluid. In another exemplary embodiment, the settable fluids of the present invention may be used as a drilling fluid.

Abstract: The present invention provides a drilling fluid composition and a method of drilling comprising a drilling fluid, which may be oil- or water-based, and a composite microsphere component. The invention drilling fluid composition advantageously reduces the density of a conventional fluid, reduces costs associated with pumping and overcomes problems associated with conventional gas-injection processes. The invention uses conventional drilling and pumping equipment, requires no sea-floor based pumps and may be easily pressure-controlled to maintain the pressure of the fluid.

Abstract: A rheology modified aqueous fluid composition comprising clay, water, magnesium oxide, aluminum oxide hydroxide, sodium carbonate or potassium carbonate, and calcium oxide or calcium hydroxide. The magnesium oxide and aluminum oxide hydroxide are prepared by a specific thermal treatment protocol involving heating of appropriate precursors within a specified temperature range. The pH of the composition is at least about 10. The composition is prepared by admixing the components and, optionally, sodium oxide or sodium hydroxide for pH adjustment as necessary. A substantially dry rheology modification agent comprising the enumerated components, not including the water, is also included. The resulting composition preferably exhibits shear-thinning capability including very rapid thinning upon application of shear forces and also rapid viscosification upon removal of such forces.

Abstract: An excavation fluid composition useful for enlarging a cavity in the earth includes a synthetic polymer and sodium silicate. The excavation fluid composition is formulated so as to enable the fluid in contact with unstable or sandy soils in the selected areas of the excavation to react and form silicate-based derivatives with lesser solubility, and movement and thus improve soil stability at the excavation wall.

Abstract: A method is provided for reducing loss of drilling fluid and for stabilizing a wellbore during drilling through depleted sands in a subterranean formation comprising depleted sands. The method comprises introducing into said wellbore and into said depleted sands an aqueous fluid comprising silicate or siliconate and resilient graphitic carbon in an amount effective at substantially plugging pores in said depleted sands.

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: The invention relates to water based wellbore fluids used during a hydrocarbon recovery process, such as drilling, fracturing, gravel packing and wellbore workover. According to the present invention, said wellbore fluid comprises a fluid loss additive and a bridging material that are hydrophobic in nature, hydrophobically modified or oil wettable. The wellbore fluid generates an active filter cake that once formed, is impermeable to an aqueous phase, thus reducing fluid loss and ensuring reduced damage to the formation, yet simultaneously is permeable to the back flow of hydrocarbons during a hydrocarbon recovery process.

Abstract: A wellbore fluid including a peroxide degradable polymer and an encapsulated peroxide source. The peroxide degradable polymer may be a polysaccharide. The peroxide source may include an inorganic peroxide, including zinc and alkaline earth metal peroxides, such as magnesium peroxide. The encapsulating material may be a polymer, including enteric polymers. The release of peroxide, from peroxide sources generally, can be controlled by means of pH such that peroxide source can be activated, and peroxide released, by a change in pH. In a wellbore, this pH change can be effected by using produced fluids to lower the pH of a more basic wellbore fluid.

Abstract: A method and composition is provided for sealing a subterranean zone penetrated by a well bore to restore lost circulation. In one embodiment, the composition comprises a pellet comprising a mixture of lost circulation materials (LCMs).

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

Abstract: Methods of forming chemical casings include drilling a well bore with a drilling fluid having a pH in the range of from about 6 to 10 and comprising water, a water soluble or water dispersible polymer which is capable of being cross-linked by a thermoset resin and causing the resin to be hard and tough when cured, a particulate curable solid thermoset resin, a water soluble or dispersible thermoset resin, and a delayed dispersible acid-catalyst for curing the solid thermoset resin and the water soluble thermoset resin, whereby the drilling fluid forms a filter cake on the walls of the wellbore that cures into a hard and tough cross-linked chemical casing thereon.

Abstract: The present invention relates to subterranean operations, and more particularly, to settable fluids comprising vitrified shale and hydrated lime and methods of using such settable fluids in subterranean applications. In an exemplary embodiment, the settable fluids of the present invention may be used as a displacement fluid. In another exemplary embodiment, the settable fluids of the present invention may be used as a drilling fluid.

Abstract: A water-based, shear-thinning process fluid comprises bentonite, aluminium hydroxide particles, and salt. The median diameter (by weight) of the aluminium hydroxide particles does not exceed 2 &mgr;m.

Abstract: A dense drilling fluid additive used to control lost circulation, fluid loss and/or seepage loss of drilling fluid during drilling operations is disclosed. Such additive is formed from ground base materials, such as inorganic matter, and may be used to manage the rheological properties of drilling fluid.

Abstract: A drilling fluid additive is provided wherein the additive is manufactured by a method comprised of admixing colloidal solids such as talc with at least one carrier such as an oil or glycol to create a suspended mixture to thereby allow the colloidal solids to be pre-wet with the carrier; and then admixing copolymer beads to the suspended mixture.

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.