Abstract: Treatment method for a rock formation against sand infiltration during production of fluid from this rock formation via a well drilled through said rock formation, comprising at least one step of injecting a geopolymer cement grout into said rock formation, in particular around the edges of said well and/or through said well.

Abstract: The positions of hydraulic fractures may be detected during multistage reservoir stimulation operations. Fracturing fluid is injected into a well at a pressure above the fracturing pressure to produce at least one hydraulic fracture. Then, a marker slug is injected into the well. Next, additional fracturing fluid is injected into the well. When the marker slug enters at least one of the hydraulic fractures, a detectable pressure response is observed, and the position of a hydraulic fracture may be detected from the volume of fracturing fluid injected after injection of the marker slug. The marker slug is a fluid that has a viscosity and/or density that is different from the fracturing fluids injected before and after the marker slug. This technique may be combined with other well operations, such as plugging at least one hydraulic fracture or creating at least one new hydraulic fracture.

Abstract: A spacer fluid made of a viscosity thinner, a weighting agent, an antifoaming agent, and a non-ionic surfactant in a base aqueous fluid is disclosed. In some instances, the viscosity thinner is a sulfomethylated tannin, the weighting agent is barium sulfate, the antifoaming agent is a silicone, and the non-ionic surfactant is an ethoxylated alcohol. A method of treating a well bore annulus in preparation of introducing water-based cement slurry into a well bore using the spacer fluid is disclosed. A method of using the spacer fluid to position a first fluid into a well bore annulus of a well bore containing a second fluid is disclosed. A method for fluidly isolating at least a portion of a well bore annulus in a well bore containing an oil-based drilling fluid using water-based cement slurry and the spacer fluid is disclosed.

Abstract: A method of treating an earthen formation that includes introducing a first amount of a first blocked isocyanate in a liquid phase into the earthen formation; introducing a second amount of a second blocked isocyanate in a liquid phase into the earthen formation; the second blocked isocyanate group having a lower unblocking temperature than the first blocked isocyanate group; introducing at least one active hydrogen compound into the earthen formation; and contacting the first and second blocked isocyanates and the active hydrogen compound to form an elastomeric gel. The combination of two blocked isocyanates provides a synergistic effect so that the curing time can be optimised in a manner unexpected from the properties of the individual blocked isocyanates.

Abstract: Novel nonionic cellulose ethers exhibit a reduced degree of thermal thinning and are efficient thickeners at elevated temperatures. The nonionic cellulose ether has hydroxyethyl groups and is further substituted with one or more hydrophobic substituents. The cellulose ether further has at least one of the properties a), b) or c): a) a retained dynamic viscosity, % ?80/25, of at least 30 percent, wherein % ?80/25=[dynamic solution viscosity at 80° C./dynamic solution viscosity at 25° C.] 100, the dynamic solution viscosity at 25° C. and 80° C. being measured as 1% aqueous solution; b) a storage modulus of at least 15 Pascals at 25° C. and a retained storage modulus, % G?80/25, of at least 12 percent, wherein % G?80/25=[storage modulus at 80° C./storage modulus at 25° C.] 100, the storage modulus at 25° C. and 80° C. being measured as a 1% aqueous solution; c) a critical association concentration of less than 15 ppm as measured by light-scattering.

Abstract: A ceramic propping agent, in the form of a spherical pellet, and containing common mineral particulate. The desired propping agent is defined as a particulate ceramic made from raw materials which may be comprised of about: 10%-90% parts by weight of a naturally occurring mineral particulate, 30%-70% parts by weight aluminosilicate network modifier, 0.25-20% parts by weight strength enhancer, and at least one part, typically less than 10% by weight, binder. For use in oil and/or natural gas wells as a hydraulic fracturing proppant.

Abstract: A cement composition for use in an oil or gas well, the cement composition comprises: a calcium aluminate cement; water; an organic acid; and a polymeric mixture comprising: (A) water; (B) citric acid; (C) a first polymer, wherein the first polymer: (i) comprises a cellulose backbone and carboxymethyl functional groups; and (ii) has a molecular weight of less than 100,000; and (D) a second polymer, wherein the second polymer: (i) comprises a lignosulfonate; and (ii) has a molecular weight of less than 100,000, wherein a test composition consisting essentially of: the cement; the water; the organic acid; and the polymeric mixture, and in the same proportions as in the cement composition has a thickening time of at least 5 hours at a temperature of 300° F. (148.9° C.) and a pressure of 10,000 psi (68.9 MPa).

Abstract: A ceramic propping agent, in the form of a spherical pellet, and containing common mineral particulate. The desired propping agent is defined as a particulate ceramic made from raw materials which may be comprised of about: 10%-90% parts by weight of a naturally occurring mineral particulate, 30%-70% parts by weight aluminosilicate network modifier, 0.25-20% parts by weight strength enhancer, and at least one part, typically less than 10% by weight, binder. For use in oil and/or natural gas wells as a hydraulic fracturing proppant.

Abstract: A treatment fluid for a well includes: (a) a water-soluble polymer, wherein the water-soluble polymer comprises a polymer of at least one non-acidic ethylenically unsaturated polar monomer; (b) an organic crosslinker comprising amine groups, wherein the organic crosslinker is capable of crosslinking the water-soluble polymer; (c) a weak organic acid; and (d) water; wherein the treatment fluid is a crosslinkable polymer composition.

Abstract: A process for treating an earth formation is disclosed, the process may include: injecting a gelling agent into the earthen formation; injecting a crosslinking agent into the earthen formation; and reacting the gelling agent and the crosslinking agent to form a gel. The gelling agent may include at least one of a lignin, a lignosulfonate, a tannin, a tannic acid, a modified lignin, a modified lignosulfonate, a modified tannin, a modified tannic acid, biopolymers, starches, carboxy methyl cellulose, polyacrylates, polyacrylamides, polyamines, polyether amines, poly vinyl amines, polyethylene imines, and combinations thereof.

Abstract: Non-settable spacer fluids for use in subterranean operations comprising: a base liquid; vitrified shale; a chelating agent; a clay weighting agent; and a viscosifying agent. The chelating agent includes one or more of nitrilotriacetic acid, ethylene diamine tetracetic acid (EDTA), ethylene glycol tetraacetic acid (EGTA), tartaric acid, a polycarboxylic acid, a lignosulphonate, hydroxyethylidene diphoshponic acid (HEDP), diethylene triamine penta (methylene phosphonic) acid (DETMP), amino-tri-methylene phosphonic acid (ATMP), ethylene diamine tetra (methylene phosphonic) acid (EDTMP), or salts thereof. The clay weighting agent is present in the range of about 0.01% to about 85% by weight of the spacer fluid. The viscosifying agent is present in the range of about 1% to about 10% by weight of the spacer fluid.

Abstract: The present invention provides a versatile additive for improving the properties of a cement slurry made with portland cement and to be utilized in well cementing, said versatile additive comprising type of silicates and/or borates that inhibit gelation occurring with the interstitial phase. The additive of the present invention improves significantly the rheology (i.e., strong dispersing effect) and can even overcome severe gelation problems. At temperature above about 88° C. (190° F.) the additive acts as retarder aid, enabling to reduce considerably the concentration of retarder required to achieve a given thickening time.

Abstract: Exemplary embodiments of the cement compositions comprise water, a cement, and a fluid loss control additive, the fluid loss control additive comprising a graft copolymer. The graft copolymer comprises a backbone and at least four grafted monomers selected from the group consisting of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, acrylic acid, vinylphosphonic acid, diallyldimethylammonium chloride, and salts thereof. The backbone of the graft copolymer comprises a humic acid salt. Methods of cementing using exemplary embodiments of the cement compositions are also provided.

Abstract: A method of treating a formation that includes emplacing an oxidizing breaker fluid into a region of the formation occupied by a gel; and allowing sufficient time for the oxidizing breaker fluid to degrade the gel is disclosed.

Abstract: Methods of improving shear recovery time of viscoelastic surfactant fluid systems are described, one method involving providing a viscoelastic surfactant fluid system comprising a major portion of a surfactant and a rheology enhancer in a concentration sufficient to shorten shear recovery time of the fluid system compared to shear recovery time of the fluid system absent the rheology enhancer, the rheology enhancer selected from aromatic sulfonates having a molecular weight of at least 500; and injecting the fluid system down a well. The rheology enhancer may be a lignosulfonate derived from wood pulping. Viscoelastic surfactant systems including the rheology enhancer are also described.

Abstract: Chemical wash compositions comprising a sulfonated lignin and a taurate are provided. In one embodiment, a chemical wash composition is provided comprising water, a sulfonated lignin, and a taurate.

Abstract: Exemplary embodiments of the cement compositions comprise water, a cement, and a fluid loss control additive, the fluid loss control additive comprising a graft copolymer. The graft copolymer comprises a backbone and at least four grafted monomers selected from the group consisting of 2-acrylamido-2-methylpropanesulfonic acid, acrylamide, acrylic acid, vinylphosphonic acid, diallyldimethylammonium chloride, and salts thereof. The backbone of the graft copolymer comprises a humic acid salt. Methods of cementing using exemplary embodiments of the cement compositions are also provided.

Abstract: Methods of improving shear recovery time of viscoelastic surfactant fluid systems are described, one method involving providing a viscoelastic surfactant fluid system comprising a major portion of a surfactant and a rheology enhancer in a concentration sufficient to shorten shear recovery time of the fluid system compared to shear recovery time of the fluid system absent the rheology enhancer, the rheology enhancer selected from aromatic sulfonates having a molecular weight of at least 500; and injecting the fluid system down a well. The rheology enhancer may be a lignosulfonate derived from wood pulping. Viscoelastic surfactant systems including the rheology enhancer are also described.

Abstract: Methods and compositions are provided for treating fluids, especially spacer fluids and cement compositions as well as drilling, completion and stimulation fluids including, but not limited to, drilling muds, well cleanup fluids, workover fluids, conformance fluids, gravel pack fluids, acidizing fluids, fracturing fluids and the like for introduction into a subterranean zone penetrated by a wellbore, wherein the treating fluid comprises zeolite and a carrier fluid. The treating fluid may additionally include one or more of a viscosifier, organic polymer, dispersants, surfactants and weighting materials.

Abstract: A method is given for reducing fluid loss in downhole operations such as drilling and completion. A composition containing a fusing solid is injected into the fluid loss flow path; the fusing solid fuses at formation temperature when the injection pressure is released and the formation matrix surfaces forming the flow path close on the composition. The fusing solid is gilsonite, or a similar material, or resin coated particles. The composition may optionally contain one or more of fibers, flakes, an activator, and a dispersant.

Abstract: Methods of improving shear recovery time of viscoelastic surfactant fluid systems are described, one method involving providing a viscoelastic surfactant fluid system comprising a major portion of a surfactant and a rheology enhancer in a concentration sufficient to shorten shear recovery time of the fluid system compared to shear recovery time of the fluid system absent the rheology enhancer, the rheology enhancer selected from aromatic sulfonates having a molecular weight of at least 500; and injecting the fluid system down a well. The rheology enhancer may be a lignosulfonate derived from wood pulping. Viscoelastic surfactant systems including the rheology enhancer are also described.

Abstract: The present application relates to granules of powdery mineral particles produced by spray granulation of a liquid slurry comprising powdery minerals particles having particle size below 10 m, at least one water-reducing agent and/or at least one binder agent and/or at least one dispersing agent. The application further relates to a method for producing such granules.

Abstract: A drilling fluid or mud additive 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; 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 tanks. 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. Hydration buffers help keep the powder or pellets dry and flowable.

Abstract: Improved casing strings, and methods of using improved casing strings in subterranean cementing operations, are provided. An example of an apparatus is a pipe string comprising at least one pipe section and a delivery system of an activator. Another example of an apparatus is a pipe string comprising at least one pipe section and a delivery system of a set retarder. An example of a method is a method of cementing in a subterranean formation. Other examples of methods are methods of cementing in a subterranean formation comprising a well bore.

Abstract: Zeolite and Class F fly ash compositions are provided for use as cement-free settable fluids such as settable spotting fluids and cementitious compositions.

Abstract: A process for treating an earth formation is disclosed, the process may include: injecting a gelling agent into the earthen formation; injecting a crosslinking agent into the earthen formation; and reacting the gelling agent and the crosslinking agent to form a gel. The gelling agent may include at least one of a lignin, a lignosulfonate, a tannin, a tannic acid, a modified lignin, a modified lignosulfonate, a modified tannin, a modified tannic acid, biopolymers, starches, carboxy methyl cellulose, polyacrylates, polyacrylamides, polyamines, polyether amines, poly vinyl amines, polyethylene imines, and combinations thereof.

Abstract: The subject of the present invention is the use of particular polysaccharides as admixtures for mineral materials, especially as admixtures for mineral binders. These polysaccharides have, characteristically: a weight-average molecular weight Mw of at least 500 g/mol and at most 9000 g/mol, especially between 700 and 7000 g/mol; and a degree of branching DB of at least 10%, especially between 10 and 40%. The invention also relates to the combined use, in mineral materials, including especially mineral binders, of these particular polysaccharides on the one hand and of certain other admixtures on the other hand, for example admixtures, of saccharidic or nonsaccharidic type, having a plasticizing, superplasticizing or other functionality.

Abstract: A material and a device for releasing chemicals in a fluid environment is disclosed, and a method for releasing substances into downhole fluid environments. The invention also relates to materials for sand control and hydraulic fracturing. The substance release device typically comprises a polymeric material for releasing a substance into a downhole fluid environment in a well, and in preferred embodiments the material comprises a spherical, plastic chemical release capsule which is hard, permeable and may encapsulate a range of solids and/or liquids for subsequent release. These solids or liquids can include inhibitors such as scale inhibitors and other oilfield production chemicals for release into the wellbore of an oil or gas producing well or a water injection well.

Abstract: The invention is a method for improving conformance during a carbon dioxide foam flood, which comprises injecting into the formation an aqueous solution of about 0.05% to about 5% by weight of a carbon dioxide foaming surfactant, and about 0.05% to about 5% by weight of a lignosulfonate-acrylic acid graft copolymer having about 2% to about 70% by weight of acrylic acid, and injecting into the formation carbon dioxide to sweep the hydrocarbons towards a production well for recovery.

Abstract: Methods are provided for stimulation of hydrocarbon production from low permeability formations by hydraulic fracturing, acid fracturing, and hydraulic fracturing followed by gravel packing in a single operation. The methods use a first injected viscous pad made with low concentration uncrosslinked polymer to initiate and propagate the fracture and control fluid loss, followed by a second injected fluid gelled with a viscoelastic surfactant for carrying proppant or acid into the fracture.

Abstract: Well-working fluid compositions containing certain processed inorganic, oil and water wettable ground elastomeric crumb rubber materials to decrease the seepage loss of various fluids to subterranean formations in which these well working fluids are required and utilized are disclosed. Also disclosed is a method of reducing the seepage and whole mud loss of these well working fluids utilizing such ground elastomeric crumb rubber materials.

Abstract: The present invention provides methods and compositions for removing a water-based drilling fluid from surfaces in a well bore and leaving the surfaces water-wet. A method of the invention basically comprises the following steps. A water-based drilling fluid removal solution comprised of water and a mixture of a sulfonated kraft lignin salt and an N-methyl-N-oleyltaurine salt dissolved therein is provided. The drilling fluid is displaced from the well bore and the well bore surfaces are contacted with the removal solution to thereby remove the drilling fluid from the surfaces and make the surfaces water-wet.

Abstract: Liquid suspensions of particles 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 particles. The suspensions enable a user to rapidly add the suspension to water and to mix at low speeds without generating fugitive dust in the process. In addition, a liquid dispersion can provide an easy to use liquid containing higher concentrations of the active dispersed phase than can be accomplished by simply preparing an aqueous solution of the dispersed phase. Alternatively, highly water-soluble particles may also be suspended which have poor storage, freeze/thaw, or heat/cool stability. In some cases, liquid dispersions can yield controlled release of the dispersed phase because the dispersed phase is not in aqueous solution. The suspensions are environmentally safe and biodegradable and may be used in environmentally sensitive applications, such as for oil well treating fluids for offshore areas.

Abstract: A method for enhancing the stability of a solids-stabilized water-in-oil emulsion by pretreating the oil prior to emulsification. The pretreatment step can be accomplished by adding dilute acid to the oil, adding a lignosulfonate additive to the oil, sulfonating the oil, thermally oxidizing the oil, thermally treating the oil in an inert environment, and combinations thereof. The emulsion can be used in enhanced oil recovery methods, including using the emulsion as a drive fluid to displace hydrocarbons in a subterranean formation, and using the emulsion as a barrier fluid for diverting flow of fluids in the formation.

Abstract: The present invention provides methods and compositions for removing a water-based drilling fluid from surfaces in a well bore and leaving the surfaces water-wet. A method of the invention basically comprises the following steps. A water-based drilling fluid removal solution comprised of water and a mixture of a sulfonated kraft lignin salt and an N-methyl-N-oleyltaurine salt dissolved therein is provided. The drilling fluid is displaced from the well bore and the well bore surfaces are contacted with the removal solution to thereby remove the drilling fluid from the surfaces and make the surfaces water-wet.

Abstract: A method for promoting cement or concrete set on demand for concrete that has been chemically retarded by adding carbon fiber to the concrete, which enables it to become electrically conductive, sodium tartrate retardant, and copper sulfate which forms a copper tartrate complex in alkaline concrete mixes. Using electricity, the concrete mix anodically converts the retarding tartrate to an insoluble polyester polymer. The carbon fibers act as a continuous anode surface with a counter electrode wire embedded in the mix. Upon energizing, the retarding effect of tartrate is defeated by formation of the polyester polymer through condensation esterification thereby allowing the normal set to proceed unimpeded.

Abstract: The present invention provides methods and compositions for removing a water-based drilling fluid from surfaces in a well bore and leaving the surfaces water-wet. A method of the invention basically comprises the following steps. A water-based drilling fluid removal solution comprised of water and a mixture of a sulfonated kraft lignin salt and an N-methyl-N-oleyltaurine salt dissolved therein is provided. The drilling fluid is displaced from the well bore and the well bore surfaces are contacted with the removal solution to thereby remove the drilling fluid from the surfaces and make the surfaces water-wet.

Abstract: Sulfonated uintaite is prepared by sulfonating a naturally occurring uintaite charge with a sulfonating agent such as sulfur trioxide, fuming sulfuric acid, chlorosulfonic acid, oleum, or concentrated sulfuric acid to produce sulfonic acids of uintaite. The resulting sulfonic acids are neutralized with a caustic neutralizing agent and sulfonated uintaite is the product. The sulfonated uintaite product is dried and packaged. The produced sulfonated uintaite is useful in oil and gas well working fluids (drilling muds). Neutralization of the resulting sulfonic acids with sodium hydroxide or ammonium hydroxide as the caustic neutralizing agent yields water and oil-soluble or dispersible salts of the sulfonated uintaite. Neutralization with Ca(OH)2 (calcium hydroxide) as the caustic neutralizing agent yields a product which is preferable in oil-based muds.

Abstract: A method for reducing the permeability of a region of an underground formation by injecting a gelant solution that forms a stable gel into the region is disclosed. The gelant solution includes an aqueous solvent, about 2% to about 16% by weight of a lignosulfonate-acrylic acid graft copolymer and a sufficient concentration of a crosslinking agent to crosslink the copolymer. The lignosulfonate-acrylic acid copolymer used in the invention has an acrylic acid content of about 10% to about 50% by weight and the crosslinking agent is a complex of one or more positively charged chromium (III) species and one or more negatively charged carboxylate species. Preferably, the chromium (III) species used in the invention has a concentration of about 0.1% to about 8.0% by weight. In one preferred embodiment, the carboxylate species of the crosslinker may be selected from formate, acetate, propionate, lactate, oxalate and malonate.

Abstract: A subterranean formation is treated to inhibit adsorption of asphaltenes by injecting a treatment fluid containing a sacrificial compound, such as a lignosulfonate. The lignosulfonate may be adsorbed onto formation surfaces in such a way as to act to inhibit the adsorption of asphaltenes. A pretreatment fluid for removing asphaltenes may be injected into the formation before the treatment fluid. The pretreatment fluid may contain an organic solvent, such as terpene.

Abstract: A blended additive composition, which is useful for thinning aqueous drilling fluids, is disclosed. The composition includes a first component selected from the group including: a modified tannin, a modified lignite and sodium lignosulfonate; a second component being a polymer prepared from acrylic acid; and a third component being a metal compound selected from the group of metals including iron, tin, chromium, manganese, titanium, aluminum and zinc.