| Patent application number | Description | Published |
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| 20080202744 | Methods and Compositions for Fracturing Subterranean Formations - 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. | 08-28-2008 |
| 20080220995 | Suspension of Concentrated Particulate Additives Containing Oil for Fracturing and Other Fluids - The handling, transport and delivery of particulate materials, particularly fine particles, may be difficult. Alkaline earth metal oxide particles such as magnesium oxide (MgO) may be suspended in glycerin and/or alkylene glycols such as propylene glycol up to loadings of 51 wt %. Such suspensions or slurries make it easier to deliver MgO and similar agents into fluids, such as aqueous fluids gelled with viscoelastic surfactants (VES). These concentrated suspensions or slurries may be improved in their stability by the inclusion of minor amounts of a vegetable oil and/or a fish oil. The MgO serves as stabilizers and/or fluid loss control agents for VES-gelled fluids used to treat subterranean formations, e.g. for well completion or stimulation in hydrocarbon recovery operations. The particle size of the magnesium oxide or other agent may be between 1 nanometer to 0.4 millimeter. | 09-11-2008 |
| 20080227672 | Unsaturated Fatty Acids and Mineral Oils as Internal Breakers for VES-Gelled Fluids - Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a synergistic internal breaker composition that contains at least one first internal breaker that may be a mineral oil and a second breaker that may be an unsaturated fatty acid. The internal breakers may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. This combination of different types of internal breakers break the VES-gelled aqueous fluid faster than if one of the breaker types is used alone in an equivalent total amount. | 09-18-2008 |
| 20080248978 | Compositions and Methods for Water and Gas Shut-Off in Subterranean Wells With VES Fluids - Viscoelastic surfactant (VES) based fluid systems for zone isolation and flow control are effective in water and/or gas shutoff applications. The fluid systems may include brine, a viscosity enhancer, as well as the VES, and optionally a stabilizer for high temperature applications. The stabilizer may be an alkali earth metal oxide, alkali earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, Al | 10-09-2008 |
| 20080271888 | Methods of Using Viscoelastic Surfactant Gelled Fluids to Pre-Saturate Underground Formations - Viscoelastic surfactant (VES) based fluid systems are effective to pre-saturate high permeability subterranean formations prior to a treatment operation that would undesirably suffer from high fluid leakoff. The fluid systems may include brine, a viscosity enhancer, as well as the VES, and a high temperature stabilizer. The stabilizer may be an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, Al | 11-06-2008 |
| 20080296024 | Procedures and Compositions for Reservoir Protection - A flow conduit having at least one orifice is placed in the vicinity of a flow source, which in one non-limiting embodiment may be a hydrocarbon reservoir. The flow pathway between the orifice and the source is temporarily blocked with a degradable barrier. Once the flow pathway is physically placed, the degradable barrier is removed under the influence of an acid, a solvent, time and/or temperature. The flow source and the flow pathways are at least partially covered (and flow blocked by) a temporary coating such as a pseudo-filter cake formed by a viscoelastic surfactant-gelled aqueous drill-in fluid, and the flow conduit is extended to the flow source. The pseudo-filter cake is removed when viscosity is reduced by an internal breaker, and flow is then allowed. The method is useful in one context of recovering hydrocarbons where the flow conduit is a telescoping sleeve or tube that contacts the borehole wall. | 12-04-2008 |
| 20080300153 | Use of Nano-Sized Clay Minerals in Viscoelastic Surfactant Fluids - Nano-sized clay minerals enhance the viscosity of aqueous fluids that have increased viscosity due to the presence of viscoelastic surfactants (VESs). In one non-limiting theory, the nano-sized clay mineral viscosity enhancers associate, link, connect, or relate the VES micelles thereby increasing the viscosity of the fluid, possibly by mechanisms involving chemisorption or surface charge attractions. The nano-sized clay particles may have irregular surface charges. The higher fluid viscosity is beneficial to crack the formation rock during a fracturing operation, to reduce fluid leakoff, and to carry high loading proppants to maintain the high conductivity of fractures. | 12-04-2008 |
| 20090065209 | Multifunctional Nanoparticles for Downhole Formation Treatments - 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, and may also help control fluid loss. When the particle size of the magnesium oxide or other particulate agent is a nanometer scale, for instance having a mean particle size of 100 nm or less, that scale may provide 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 deposited into a proppant pack in a fracture. | 03-12-2009 |
| 20090107673 | Nano-Sized Particle-Coated Proppants for Formation Fines Fixation in Proppant Packs - A fracturing fluid, gravel pack fluid and/or frac pack fluid containing particles such as proppants, gravel and/or sand, may contain an effective amount of a nano-sized 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 nano-sized particulate additive is bound to the particles with a coating agent such as an oil. 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. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon-based. | 04-30-2009 |
| 20090192053 | Methods and Compositions for Delayed Release of Chemicals and Particles - Agents, chemicals and particles may be controllably released at remote locations, such as pre-selected or predetermined portions of subterranean formations, by binding or associating or trapping them with an association of micelles formed by a viscoelastic surfactant (VES) in an aqueous base fluid to increase the viscosity of the fluid. An internal breaker within the association of micelles disturbs the association of micelles at some later, predictable or predetermined time thereby reducing the viscosity of the aqueous viscoelastic treating fluid and releasing the agent, chemical or particle at a predetermined or selected location. | 07-30-2009 |
| 20090192056 | Friction Loss Reduction in Viscoelastic Surfactant Fracturing Fluids Using Low Molecular Weight Water-Soluble Polymers - Adding relatively low molecular weight water-soluble friction loss reduction polymers to an aqueous fluid gelled with a viscoelastic surfactant (VES) increases the critical generalized Reynold's number at which the Fanning friction factor increases and friction pressure starts to increase rapidly. The water-soluble polymeric friction loss reduction additives lower surface pumping pressure in VES-gelled fracturing fluids for a given pump rate, thus lowering hydraulic horsepower (HHP) requirements for pumping fluids downhole, e.g. for hydraulic fracturing or frac packing treatments of subterranean formations. | 07-30-2009 |
| 20090253596 | FLUID LOSS CONTROL AGENTS FOR VISCOELASTIC SURFACTANT FLUIDS - Alkaline earth metal compounds may be fluid loss control agents for viscoelastic surfactant (VES) fluids used for well completion or stimulation in hydrocarbon recovery operations. The VES fluid may further include proppant or gravel, if it is intended for use as a fracturing fluid or a gravel packing fluid, although such uses do not require that the fluid contain proppant or gravel. The fluid loss control 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 fluid loss agent appears to associate with the VES micelles and together form a novel pseudo-filter cake crosslinked-like viscous fluid layer that limits further VES fluid flow into the porous media. The fluid loss control agent solid particles may be added along with VES fluids. | 10-08-2009 |
| 20090266765 | Methods for Recharging Nanoparticle-Treated Beds - Nanoparticle-treated particle packs, such as sand beds, may effectively filter and purify liquids such as waste water. Proppant beds treated with nanoparticles may fixate or reduce fines migration therethrough. When tiny contaminant particles or fines in these fluids flow through the nanoparticle-treated bed or pack, the nanoparticles will capture and hold the tiny contaminant or fines particles within the pack due to the nanoparticles' surface forces, including, but not necessarily limited to van der Waals and electrostatic forces. Nanoparticle-treated beds or packs may be recharged by contacting the bed with an inorganic acid (but not hydrofluoric acid) or an organic acid, and optionally followed by subsequent treatment with hydrofluoric acid. This treating substantially removes the nanoparticles and the fine particulates that have been removed from a fluid (e.g. wastewater being treated, produced fluids in a formation, etc.). The particle pack may then be re-treated or recharged with nanoparticles. | 10-29-2009 |
| 20090266766 | Wastewater Purification With Nanoparticle-Treated Bed - 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. | 10-29-2009 |
| 20090272534 | METHODS OF USING VISCOELEASTIC SURFACTANT GELLED FLUIDS TO PRE-SATURATE UNDERGROUND FORMATIONS - Viscoelastic surfactant (VES) based fluid systems are effective to pre-saturate high permeability subterranean formations prior to a treatment operation that would undesirably suffer from high fluid leakoff. The fluid systems may include brine, a viscosity enhancer, as well as the VES, and a high temperature stabilizer. The stabilizer may be an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxide, alkali metal hydroxide, Al | 11-05-2009 |
| 20090286702 | Using Nanoparticles for Water Flow Control in Subterranean Formations - Non-aqueous carrier fluids containing nano-sized particles in high concentration are effective for zone isolation and flow control in water shutoff applications for subterranean formations. The nanoparticles interact with water and solidify it to inhibit its flow, but do not have the same effect on hydrocarbons and thus selectively assist the production of hydrocarbons while suppressing water. Suitable nanoparticles include alkaline earth metal oxides, alkaline earth metal hydroxides, alkali metal oxides, alkali metal hydroxides, transition metal oxides, transition metal hydroxides, post-transition metal oxides, post-transition metal hydroxides, piezoelectric crystals, and/or pyroelectric crystals. | 11-19-2009 |
| 20090305915 | SUSPENSION OF CONCENTRATED PARTICULATE ADDITIVES CONTAINING OIL FOR FRACTURING AND OTHER FLUIDS - The handling, transport and delivery of particulate materials, particularly fine particles, may be difficult. Alkaline earth metal oxide particles such as magnesium oxide (MgO) may be suspended in glycerin and/or alkylene glycols such as propylene glycol up to loadings of 51 wt %. Such suspensions or slurries make it easier to deliver MgO and similar agents into fluids, such as aqueous fluids gelled with viscoelastic surfactants (VES). These concentrated suspensions or slurries may be improved in their stability by the inclusion of minor amounts of a vegetable oil and/or a fish oil. The MgO serves as stabilizers and/or fluid loss control agents for VES-gelled fluids used to treat subterranean formations, e.g. for well completion or stimulation in hydrocarbon recovery operations. The particle size of the magnesium oxide or other agent may be between 1 nanometer to 0.4 millimeter. | 12-10-2009 |
| 20090312201 | Nano-Sized Particles for Formation Fines Fixation - 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. | 12-17-2009 |
| 20100010106 | Metal-Mediated Viscosity Reduction of Fluids Gelled With Viscoelastic Surfactants - Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a composition that contains at least one metal ion source and optionally at least one second source. An optional second source may be a chelating agent where at least one reducing agent source may be additionally optionally used. Another optional component with the metal ion source includes a second, different metal ion source. The breaking composition is believed to directly attack the VES itself, possibly by disaggregating or otherwise attacking the micellar structure of the VES-gelled fluid, and/or possibly by changing the chemical structure of the VES to give two or more products. | 01-14-2010 |
| 20100071957 | Drill-In Fluids For Oil and Gas Reservoirs With High Carbonate Contents - Compositions Including Relatively Low Reactivity Acids, Mixed with viscoelastic surfactants (VESs) and internal breakers may serve as drill-in fluids to open underground hydrocarbon reservoirs with carbonate contents of 10 wt % or above. The drill-in fluids have low viscosities in the drilling pipe. After the fluid flows out of the drill bit, the acids react with carbonates in the formation thereby increasing the pH of the drill-in fluids causing the VES to gel the fluid at the bottom of the hole and the downhole annulus between the drilling pipe and the formation rock. The viscosified drill-in fluid will reduce fluid loss and will carry no dissolved drilling debris to the surface. After drilling through the targeted formation, the internal breakers in the viscosified drill-in fluids will break down the fluids to permit their removal, and the well is ready to produce with very little or no near well bore damage. | 03-25-2010 |
| 20100108613 | Methods and Compositions to Remove Coal Fines From Aqueous Fluids - Nanoparticle-treated particle packs, such as sand beds, may effectively remove coal fines from aqueous fluids, such as contaminated water. A porous substrate treated with nanoparticles, such as alkaline earth metal oxides/hydroxides, transition metal oxides/hydroxides, post-transition metal oxides/hydroxides, piezoelectric crystals, and/or pyroelectric crystals, may remove a substantial portion of coal fines from an aqueous fluid. It is believed that the nanoparticles capture and hold the coal fines in the particle pack due to surface forces, including van der Waals and/or electrostatic forces. The nanoparticles may be applied to the substrate via a coating agent, such as alcohol, glycol, polyol, olefin, vegetable oil, fish oil, and/or mineral oil. | 05-06-2010 |
| 20100197531 | Use of Oil-Soluble Surfactants as Breaker Enhancers for VES-Gelled Fluids - Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of an internal breaker composition that contains at least one mineral oil, at least one polyalphaolefin oil, at least one saturated fatty acid and/or at least one unsaturated fatty acid. The internal breaker may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. In one non-limiting embodiment, the internal breaker, e.g. mineral oil, is added to the fluid after it has been substantially gelled. An oil-soluble surfactant is present to enhance or accelerate the reduction of viscosity of the gelled aqueous fluid. | 08-05-2010 |
| 20100234248 | Saponified Fatty Acids as Breakers for Viscoelastic Surfactant-Gelled Fluids - Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities affected (increased or reduced, e.g. gels broken) by the indirect or direct action of a composition that contains at least one fatty acid that has been affected, modified or reacted with an alkali metal base, an alkali earth metal base, ammonium base, and/or organic base compound, optionally with an alkali metal halide salt, an alkali earth metal halide salt, and/or an ammonium halide salt. The composition containing the resulting saponification product is believed to either act as a co-surfactant with the VES itself to increase viscosity and/or possibly by disaggregating or otherwise affecting the micellar structure of the VES-gelled fluid. In a specific, non-limiting instance, a brine fluid gelled with an amine oxide surfactant may have its viscosity broken with a composition containing naturally-occurring fatty acids in canola oil or corn oil affected with CaOH, MgOH, NaOH and the like. | 09-16-2010 |
| 20100252266 | Organic Acid Treating Fluids With Viscoelastic Surfactants and Internal Breakers - An aqueous fluid system that contains an aqueous dicarboxylic acid solution, a viscoelastic surfactant as a gelling agent to increase the viscosity of the fluid, and an internal breaker such as mineral oil and/or fish oil to controllably break the viscosity of the fluid provides a self-diverting acid treatment of subterranean formations. The internal breaker may be at least one mineral oil, a polyalphaolefin oil, a saturated fatty acid, and/or is an unsaturated fatty acid. The VES gelling agent does not yield viscosity until the organic acid starts to spend. Full viscosity yield of the VES gelling agent typically occurs at about 6.0 pH. The internal breaker allows the VES gelling agent to fully viscosify the spent organic acid at 6.0 pH and higher, but as the spent-acid VES gelled fluid reaching reservoir temperature, controllable break of the VES fluid viscosity over time can be achieved. | 10-07-2010 |
| 20100261622 | Methods and Compositions for Fracturing Subterranean Formations - 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. | 10-14-2010 |
| 20100261624 | Unsaturated Fatty Acids and Mineral Oils As Internal Breakers for VES-Gelled Fluids - Fluids viscosified with viscoelastic surfactants (VESs) may have their viscosities reduced (gels broken) by the direct or indirect action of a synergistic internal breaker composition that contains at least one first internal breaker that may be a mineral oil and a second breaker that may be an unsaturated fatty acid. The internal breakers may initially be dispersed oil droplets in an internal, discontinuous phase of the fluid. This combination of different types of internal breakers break the VES-gelled aqueous fluid faster than if one of the breaker types is used alone in an equivalent total amount. | 10-14-2010 |
| 20100263866 | Multifunctional Particles for Downhole Formation Treatments - 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. | 10-21-2010 |
| 20100270022 | Deep Water Completions Fracturing Fluid Compositions - It has been discovered that fracturing fluid compositions can be designed for successful deep water completion fracturing fluid operations. These fluids must be pumped relatively long distances from offshore platforms to the reservoir, and they are often subjected to a wide temperature range. Under these conditions, it is necessary to inhibit the formation of gas hydrates in the fracturing fluid compositions, as well as to delay the crosslinking of the gels that are formed to increase the viscosity of the fluids prior to fracturing the formation. Preferably, two different gas hydrate inhibitors are used to ensure placement of a gas hydrate inhibitor in most parts of the operation. In addition, as with all offshore or deep water hydrocarbon recovery operations, it is important that the components of the fracturing fluid compositions be environmentally benign and biodegradable. | 10-28-2010 |
| 20100286000 | Nano-Sized Particle-Coated Proppants for Formation Fines Fixation in Proppant Packs - A fracturing fluid, gravel pack fluid and/or frac pack fluid containing particles such as proppants, gravel and/.or sand, may contain an effective amount of a nano-sized 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 nano-sized particulate additive is optionally bound to the particles with a coating agent such as an oil, alcohol, glycol, glycol ethers, ketones, terpenes, etc. The particle size of the magnesium oxide or other agent may be nanometer scale but may be a larger scale than nanometer but still relatively small, which scale may provide unique particle charges that help fixate the formation fines. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon-based. | 11-11-2010 |
| 20100314108 | Dual-Function Nano-Sized Particles - Dual-function nano-sized particles or nanoparticles may be effective at fixating or reducing fines migration and they may facilitate identification of a particular zone in a well having more than one zone. In some embodiments the dual-function nanoparticles are tagged with a detectable material that is distinguishable from the composition of the primary nanoparticle component. In these embodiments, the taggant material rather than the primary component of the nanoparticles may be used to enable identification of a particular zone. The nanoparticles (with or without taggant) may be added to a treatment fluid containing carrier particles such as proppant. The treatment fluid is pumped downhole to one of the zones; each zone receiving its own unique or uniquely-tagged nanoparticles. Should one of the zones fail, the composition of the nanoparticles (or its taggant) produced on the carrier particles may be correlated to the zone from which it was received, and hence produced. | 12-16-2010 |
| 20100314113 | Dual-Functional Breaker for Hybrid Fluids of Viscoelastic Surfactant and Polymer - Incorporating water-based polymer breakers, such as oxidizers, enzymes and/or acids, into a mixture of an oil and oil-soluble surfactants creates an emulsion that can then perform as a dual-functional breaker for reducing the viscosity of hybrid fluids gelled with both a viscoelastic surfactant (VES) and a polymer. The outer phase of the dual-functional breaker emulsion is oil, e.g. a mineral oil, containing an oil-soluble surfactant that will, over time and with heat, break the VES portion of the gel. As it does so, the polymer breaker in the internal aqueous phase will be released to then break the polymer portion of the gel. The polymer breaker will not start to break the polymer gel before the oil-soluble surfactant starts to break the VES gel. The overall breaking using the emulsion is slower as compared to introducing the polymer breaker and the oil-soluble surfactant in a non-emulsified form. | 12-16-2010 |
| 20110030952 | METHODS OF GRAVEL PACKING LONG INTERVAL WELLS - 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. | 02-10-2011 |
| 20110083902 | Lost Circulation Control Fluids for Naturally Fractured Carbonate Formations - Compositions including relatively low reactivity acids and having a pH of from about 2 to about 5, mixed with viscoelastic surfactants (VESs) and internal breakers may serve as fluids, in a non-limiting embodiment as drill-in fluids, to open underground hydrocarbon reservoirs with carbonate contents of 10 wt % or above. The fluids initially have low viscosities. After the fluid flows out of the drill bit, the acids react with carbonates in the formation thereby increasing the pH of the fluids causing the VES to gel the fluid at the bottom of the hole and within the formation rock. Even when the subterranean formation contains naturally-occurring fractures, the viscosified fluid will reduce fluid loss into the formation. After drilling through the targeted formation, internal breakers in the viscosified fluids will break down the fluids to permit their removal, and production of the well with very little or no near well bore damage. | 04-14-2011 |
| 20110098377 | Method of Controlling Water Production Through Treating Proppants With RPMS - Water production from a subterranean formation is inhibited or controlled by pumping a fluid containing coated particles through a wellbore into the formation. The particles have been previously coated with a relative permeability modifier (RPM). Upon contact with water, the RPM coating expands or swells and inhibits and controls the production of water. The RPM may be a water hydrolyzable polymer having a weight average molecular weight greater than 100,000. The particles may be conventional proppants or gravel. | 04-28-2011 |
| 20110108270 | Re-Use of Surfactant-Containing Fluids - The components of surfactant-laden fluids, such as those used in hydrocarbon recovery operations such as for stimulation, e.g. hydraulic fracturing, may be re-used and re-cycled into components for subsequent use in a wide range of similar or different operational fluids. In particular, aqueous fluids gelled with viscoelastic surfactants and having components therein to pseudo-crosslink the elongated VES micelles and for internal breaking may be separated into its component parts by relatively inexpensive methods such as filtration. One filtration method includes contacting the surfactant-containing fluid with a particle pack having particulate additives therein which filter out or extract fine solids from the fluid. In an alternate embodiment the surfactant-laden fluid is a nano- and/or micro-emulsion wellbore cleanup fluid. | 05-12-2011 |
