Abstract: Downhole tools for pumping an acid into a wellbore prior to pumping a fracturing fluid comprise a housing and an actuator member disposed therein. The housing comprises a port that is initially placed in fluid communication with an acid so the acid can be pumped into the wellbore and is then placed in fluid communication with a fracturing fluid so the fracturing fluid can be pumped into the same location within the wellbore. The downhole tool may comprise a chamber having the acid disposed therein. Alternatively, the acid can be part of an acid slug disposed at a leading edge of a fracturing fluid being pumped through the downhole tool.

Abstract: The migration of coal fines within a bed is reduced, inhibited or constrained by contacting the fines with nanoparticles, such as magnesium oxide crystals having an average particle size of about 30 nm. These nanoparticles may coat a proppant during the fracturing of a subterranean formation to produce methane from a coal bed therein. The nanoparticles may also treat a proppant pack in a fractured coal bed. The nanoparticles cause the coal fines to thus bind to or associate with the proppants. Thus, most of the coal fines entering fractures away from the near-wellbore region will be restrained or controlled near their origin or source and the production of methane at a desired level will be maintained much longer than a similar situation than where the nanoparticles are not used.

Abstract: Nanoparticle-treated particle packs, such as sand beds, may effectively filter and purify liquids such as waste water. When tiny contaminant particles in waste water flow through the particle pack, the nanoparticles will capture and hold the tiny contaminant particles within the pack due to the nanoparticles' surface forces, including, but not necessarily limited to van der Waals and electrostatic forces. Coating agents such as alcohols, glycols, polyols, vegetable oil, and mineral oils may help apply the nanoparticles to the particle surfaces in the filter beds or packs.

Abstract: A treating fluid may contain an effective amount of a particulate additive to fixate or reduce fines migration, where the particulate additive is an alkaline earth metal oxide alkaline earth metal hydroxide, alkali metal oxides, alkali metal hydroxides transition metal oxides, transition metal hydroxides, post-transition metal oxides, post-transition metal hydroxides piezoelectric crystals and pyroelectric crystals. The particle size of the magnesium oxide or other agent may be nanometer scale, which scale may provide unique particle charges that help fixate the formation fines. These treating fluids may be used as treatment fluids for subterranean hydrocarbon formations, such as in hydraulic fracturing, completion fluids, gravel packing fluids and fluid loss pills. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon-based.

Abstract: A gel barrier may be created within an annulus in a one-step operation by combining two or more solutions within the annulus. The two solutions may include a first solution, such as a silicate solution, and a second solution that may be an aqueous hardener solution. Once the two solutions are combined and subsequently reacted together, the forming of a gel barrier may occur between a plurality of zones along the annulus. The gel barrier may then prevent a fluid from traveling between adjacent zones of the wellbore annulus.

Abstract: Water flood materials may contain an effective amount of a nano-sized particulate additive to inhibit or control the movement of fines within a subterranean formation during a water flood secondary recovery operation. The particulate additive may be an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, transition metal oxide, transition metal hydroxide, post-transition metal oxide, post-transition metal hydroxide, piezoelectric crystal, and/or pyroelectric crystal. The particle size of the magnesium oxide or other agent may be nanometer scale, which scale may provide unique particle charges that help control and stabilize the fines, e.g. clays.

Abstract: An aqueous, viscoelastic fluid gelled with a viscoelastic surfactant (VES) is stabilized and improved with an effective amount of an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxides, alkali metal hydroxides, transition metal oxides, transition metal hydroxides, post-transition metal oxides, and post-transition metal hydroxides. These fluids are more stable and have a reduced or no tendency to precipitate, particularly at elevated temperatures. The additives may reduce the amount of VES required to maintain a given viscosity. These stabilized, enhanced, aqueous viscoelastic fluids may be used as treatment fluids for subterranean hydrocarbon formations, such as in hydraulic fracturing. The particle size of the magnesium oxide or other agent may be nanometer scale, which scale may provide unique particle charges that use chemisorption, crosslinking and/or other chemistries to associate and stabilize the VES fluids.

Abstract: The migration of coal fines within a bed is reduced, inhibited or constrained by contacting the fines with nanoparticles, such as magnesium oxide crystals having an average particle size of about 30 nm. These nanoparticles may coat a proppant during the fracturing of a subterranean formation to produce methane from a coal bed therein. The nanoparticles may also treat a proppant pack in a fractured coal bed. The nanoparticles cause the coal fines to thus bind to or associate with the proppants. Thus, most of the coal fines entering fractures away from the near-wellbore region will be restrained or controlled near their origin or source and the production of methane at a desired level will be maintained much longer than a similar situation than where the nanoparticles are not used.

Abstract: Solid, particulate dicarboxylic acids may be fluid loss control agents and/or viscosifying agents for viscoelastic surfactant (VES) fluids in treatments such as well completion or stimulation in hydrocarbon recovery operations. The fluid loss control agents may include, but not be limited to, dodecanedioic acid, undecanedioic acid, decanedioic acid, azelaic acid, suberic acid, and mixtures thereof having a mesh size of from about 20 mesh to about 400 mesh (about 841 to about 38 microns). A mutual solvent or a blend of at least two alcohols subsequently added to the aqueous viscoelastic surfactant treating fluid will at least partially dissolve the solid, particulate dicarboxylic acid fluid loss control agents, and optionally also “break” or reduce the viscosity of the aqueous viscoelastic surfactant treating fluid.

Abstract: One or more openings in a zone have an adjacent screen assembly that is axially movable to a position away from the port when pressure in the tubing exceeds the annulus pressure by a predetermined value. Upon the differential being reduced below a predetermined value or when annulus pressure exceeds the tubing pressure, the screen moves over the port to block at least some of the solids in the formation or the well fluids from entering the tubing string. The screen movement can be aided by a bias force and the movement can be locked in to prevent the screen that has moved to a position over the port from moving back away from the port.

Abstract: Nanoparticle-treated particle packs, such as sand beds, may effectively filter and purify liquids such as waste water. When tiny contaminant particles in waste water flow through the particle pack, the nanoparticles will capture and hold the tiny contaminant particles within the pack due to the nanoparticles' surface forces, including, but not necessarily limited to van der Waals and electrostatic forces. Coating agents such as alcohols, glycols, polyols, vegetable oil, and mineral oils may help apply the nanoparticles to the particle surfaces in the filter beds or packs.

Abstract: A treating fluid may contain an effective amount of a particulate additive to stabilize clays, such as clays in a subterranean formation, by inhibiting or preventing them from swelling and/or migrating, where the particulate additive is an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, transition metal oxide, transition metal hydroxide, post-transition metal oxide, post-transition metal hydroxide, piezoelectric crystal, and/or pyroelectric crystal. The particle size of the magnesium oxide or other agent may be nanometer scale, which scale may provide unique particle charges that help stabilize the clays. These treating fluids may be used as treatment fluids for subterranean hydrocarbon formations, such as in hydraulic fracturing, completion fluids, gravel packing fluids and fluid loss pills. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon-based.

Abstract: An apparatus for estimating a parameter of interest includes a conduit and a reactive media in the conduit. The reactive media interacts with a selected fluid component to control a flow parameter of the conduit. The apparatus also includes at least one sensor responsive to the flow parameter. The apparatus may be used for estimating a water content of a fluid flowing from a subterranean formation. The apparatus may include a flow path configured to convey fluid from the formation. The at least one sensor may be responsive to a pressure change in the flow path caused by interaction of the reactive media with water.

Abstract: An aqueous, viscoelastic fluid gelled with a viscosifier, e.g. a viscoelastic surfactant, is stabilized and improved with an effective amount of a particulate additive such as alkaline earth metal oxides, alkaline earth metal hydroxides, transition metal oxides, transition metal hydroxides, post-transition metal oxides, and post-transition metal hydroxides. These fluids are more stable and have a reduced or no tendency to precipitate, particularly at elevated temperatures, and may also help control fluid loss. These particulate additives have unique particle charges that use chemisorption, “crosslinking” and/or other chemistries to associate and stabilize the VES fluids, and also help trap or fixate formation fines when placed in a gravel pack or a proppant pack in a fracture. Some of these effects may be more pronounced the smaller the size of the particulate additive.

Abstract: Organic material may be removed from a fluid, such as an aqueous fluid, by contacting the fluid with a surface active porous medium. The surface active porous medium includes a bed of substrate particles (e.g. sand), at least a partial coating of nanoparticles on the substrate bed, and a plurality of absorbing particles fixated on the nanoparticles. The absorbing particles may include, but are not necessarily limited to, coal fines, activated carbon, activated charcoal, activated coal and combinations thereof. The surface active porous medium may be regenerated by contacting the surface active porous medium with an acid solution to substantially remove the organic materials therefrom.

Abstract: Alkaline earth metal compounds may be fluid loss control (FLC) agents for viscoelastic surfactant (VES) fluids used for fluid loss control pills, lost circulation material pills and kill pills in hydrocarbon recovery operations. The FLC agents may include, but not be limited to oxides and hydroxides of alkaline earth metal, and in one case magnesium oxide where the particle size of the magnesium oxide is between 1 nanometer to 0.4 millimeter. The FLC agent may alternatively be transition metal oxides and/or transition metal hydroxides. The FLC agent appears to associate with the VES micelles and together form a novel pseudo-filter cake quasi-crosslinked viscous fluid layer that limits further VES fluid flow into the porous media. The FLC agent solid particles may be added along with VES fluids. The pills may also contain internal breakers to reduce the viscosity thereof so that the components of the pill may be recovered.

Abstract: Changing concentrations of brine in a gravel pack carrier fluid gelled with a viscoelastic surfactant (VES) increases the fluid efficiency for gravel packing long interval wells, such as wellbore producing interval greater than about 100 feet (about 30 m). VES-gelled fluids used as gravel packing fluids herein also include surfactants, fluid loss control agents, internal breakers and brine in addition to the grave. The viscoelasticity of fluid system can suspend and deliver high concentration of the gravels while reducing carrier fluid volume.

Abstract: Viscoelastic surfactant (VES) gelled aqueous fluids containing water, a VES, an internal breaker, a VES stabilizer, a fluid loss control agent and a viscosity enhancer are useful as treating fluids and particularly as fracturing fluids for subterranean formations. These VES-based fluids have faster and more complete clean-up than polymer-based fracturing fluids. The use of an internal breaker permits ready removal of the unique VES micelle based pseudo-filter cake with several advantages including reducing the typical VES loading and total fluid volume since more VES fluid stays within the fracture, generating a more optimum fracture geometry for enhanced reservoir productivity, and treating reservoirs with permeability above the present VES limit of approximately 400 md to at least 2000 md.

Abstract: Solid, particulate dicarboxylic acids may be fluid loss control agents and/or viscosifying agents for viscoelastic surfactant (VES) fluids in treatments such as well completion or stimulation in hydrocarbon recovery operations. The fluid loss control agents may include, but not be limited to, dodecanedioic acid, undecanedioic acid, decanedioic acid, azelaic acid, suberic acid, and mixtures thereof having a mesh size of from about 20 mesh to about 400 mesh (about 841 to about 38 microns). A mutual solvent or a blend of at least two alcohols subsequently added to the aqueous viscoelastic surfactant treating fluid will at least partially dissolve the solid, particulate dicarboxylic acid fluid loss control agents, and optionally also “break” or reduce the viscosity of the aqueous viscoelastic surfactant treating fluid.

Abstract: Emulsified acids have been used to increase production rates of oil and gas in carbonate reservoirs through acid fracturing and matrix acidizing operations. An emulsifier is used to emulsify the aqueous acid with an oil, usually diesel. Very small particles, such as colloidal clay particles and/or nanoparticles increase the stability of the emulsified acids over an elevated temperature range.