Abstract: Among many things, in some embodiments, improved viscoelastic surfactant gels that comprise non-aqueous tackifying agents, and their associated methods of use, are provided. In one embodiment, the methods comprise: providing a treatment fluid that comprises an aqueous base fluid, a non-aqueous tackifying agent, and a viscoelastic surfactant; and introducing the treatment fluid into a subterranean formation.

Abstract: Disclosed is a microemulsion well treatment microemulsion that is formed by combining a solvent-surfactant blend with a carrier fluid. In preferred embodiments, the solvent-surfactant blend includes a surfactant and a solvent selected from the group consisting of terpenes and alkyl or aryl esters of short chain alcohols. The disclosed well treatment microemulsion can be used in well remediation, stimulation and hydrogen sulfide mitigation operations. Additionally, the well treatment microemulsion can be used in the production of benzothiophenes through interaction with hydrogen sulfide.

Abstract: A thermal insulating fluid contains microspheres of hollow spherical particulates. The presence of the hollow spherical particles improves the thermal insulating properties of the fluid by imparting to the thermal insulating fluid a low heat transfer coefficient. The hollow particulates may be inorganic or organic in nature and include hollow spheres of glass, ceramics and plastics. The thermal insulating fluid is capable of controlling the heat transfer from a production tubing or transfer pipe to one or more surrounding annuli and the environment. In addition to reducing heat transfer in the producing well, heat transfer in the fluid produced from the well is also minimized.

Abstract: Latex drag reducers and systems for delivering latex drag reducers are disclosed. The latex drag reducers comprise a polymer that is formed via an emulsion polymerization reaction dispersed in a continuous phase and can undergo subsequent modification in order to increase the solubility of the polymer in hydrocarbons. The polymers generally present a particle size of less than about 1000 nm and are suitable for delivery to a subsea flowline via a small diameter conduit of an umbilical line without an unacceptable level of pressure drop or plugging of the conduit.

Abstract: A system for reducing pressure drop associated with turbulent fluid flow through conduits located in remote locations (e.g., deep under ground and/or deep under sea). Such reduction in pressure drop is accomplished by transporting a drag reducer through a long conduit of small diameter and thereafter injecting the drag reducer into a host fluid at the remote location, to make a treated fluid. The treated fluid is then extracted from the remote location via a production/transportation conduit. The presence of the drag reducer in the treated fluid reduces pressure drop associated with flow through the production/transportation conduit.

Abstract: The present invention provides a packer cup system for use inside a wellbore comprising a packer cup and a backup component coupled thereto. In one configuration, the backup component further comprises an angled support member and a rubber ring disposed between the angled support member and the packer cup. The support member is configured to facilitate uniform expansion of the rubber ring.

Abstract: A method of depolymerizing galactomannan-type polysaccharide polymers and xanthan, preferably galactomannans, to a pre-selected lower molecular weight by irradiation with high energy electron beams. The preferred galactomannans for treatment according to this method are guar gum, guar splits and hydroxypropyl guar. In a preferred embodiment the guar gum is depolymerized preferably to a molecular weight of about 150,000 Daltons to about 200,000 Daltons. The depolymerized guar has a polydispersity of less than about 3.0 and is useful in oil well fracturing to enhance oil production.

Abstract: A method for enhancing the stability of a water-in-oil emulsion pretreating at least a portion of the oil prior to emulsification. The pretreatment step may consist of adding polymers to the oil, biotreating the oil, photochemically treating the oil, or combinations thereof. The emulsion may be used in various enhanced oil recovery methods including using the emulsion as a flooding agent to displace hydrocarbons in a subterranean formation, and using the emulsion as a barrier fluid for diverting flow of fluids in the formation.

Abstract: Alcohol based hydraulic fracturing fluids useful for treating oil and gas wells are disclosed. The fluids are compatible with carbon dioxide, and comprise an alcohol, a polymer, a crosslinking agent, and a breaker. Hydroxypropyl guar with a molar substitution of about 1.2 to about 2.2 is identified as a presently preferred polymer.

Abstract: Compressed bentonite-containing nodules are disclosed as are methods for their production and methods for using them to plug wells.

Abstract: It has been discovered that sticking caused by proppants used in a frac pack or gravel pack operation during hydrocarbon recovery efforts can be mitigated by placing a proppant anti-sticking fluid in a downhole space, such as an annulus adjacent a tool system or service tool. An operation is conducted that involves passing a carrier fluid including a proppant through the tool system. The carrier fluid is gelled and optionally crosslinked. The proppant anti-sticking fluid is flushed through the tool system to break the gel, contact the proppant and substantially clear the proppant from the tool system. Finally, the tool system is removed from downhole. The proppant anti-sticking fluid includes a diluent, such as an aqueous fluid, a brine, or a non-aqueous fluid, and an effective amount of a gel-breaking component to break the gel, and may, but does not necessarily include a surface tension-reducing compound, such as a surfactant.

Abstract: Methods and compositions are disclosed for controlled addition of components that decrease the viscosity of the viscoelastic surfactant fluids or for controlled changes in the electrolyte concentration or composition of the viscoelastic surfactant fluids. One aspect of the invention relates to the use of internal breakers with a delayed activation. Another aspect of the invention relates to the use of precursors that release a breaking system such as alcohol by a process such as melting, slow dissolution, reaction with a compound present in the fluid or added to the fluid during or after the step of injecting, rupture of an encapsulating coating and de-adsorption of a breaking agent absorbed into solid particles. In another aspect of the invention, alcohols are included in a pad to reduce the low-shear viscosity and reduce the resistance to flow of the treatment fluids during a desired phase of the treatment.

Abstract: Water-based fluids that can viscosify under shear or can produce a gel or form a gel under shear are obtained by dissolving polymers in an aqueous phase. These polymers comprise three types of functional groups: non-ionic functional groups that are hydrosoluble at the temperature under consideration, ionic functional groups, and functional groups that are hydrophobic at the temperature under consideration. These three types of functional groups can be distributed or spread in a random distribution along the polymer chain. A slightly block distribution is acceptable. For applications to oil wells, functional groups are used which exhibit LCST (Lower Critical Solution Temperature) behavior (i.e., a low critical solution temperature) instead of hydrophobic functional groups. At temperatures below the LCST, the functional groups are hydrophobic.

Abstract: The present invention relates to petroleum recovery operations, and more particularly, to the use of pulse technology to enhance the effectiveness of waterflooding operations. The systems of the present invention generally comprise an injection means for continually injecting a fluid into the subterranean formation, and a pressure pulsing means for periodically applying a pressure pulse having a given amplitude and frequency to the fluid while the fluid is being injected into the subterranean formation.

Abstract: An aqueous oilfield treatment fluid containing a chelating agent and an HF source is described. This fluid is effective at dissolving siliceous materials such as clays and keeping the dissolved materials in solution. In particular it is effective at preventing re-precipitation of initially-dissolved silicon as silica and therefore reduces damage to sandstones with which it is contacted. Methods are given for using this fluid for sandstone matrix stimulation, removal of clay-containing drilling fluid components and filter cakes from wellbores, sandstone acid fracturing, and gravel pack and proppant pack cleaning.

Abstract: A lost-circulation-material includes: rubber particulates; crosslinked-copolymer particulates; cellulosic particulates; an expandable clay; a hydrogel material, and optionally a thickener. The average size of the particulates is selected so that each of the rubber particulates, crosslinked-copolymer particulates, and cellulosic particulates differ by at least a factor of 2 in diameter from one another. The components are admixed with fresh water having low salinity to form a remedial plug. In one embodiment, the copolymer particulates are pre-formed beads; the rubber particulates are finely ground butyl rubber compound; the expandable clay includes smectite; the hydrogel includes a partially hydrolyzed polyacrylamide compound; and the cellulosic particulates are wood flour. Methods of forming a slurry for plugging lost-circulation zones, and methods of treating wellbores with the slurry, are described.

Abstract: Non-toxic high temperature stabilizers are described for compositions for treating subterranean formations using fluids that are hydrated from dry mix blends using controlled release methods of particle dissolution. In particular, one aspect of this invention is a dry blended particulate composition for hydraulic fracturing containing a particulate hydratable polysaccharide, a particulate crosslinking agent, a slowly releasing particulate base, and a non-toxic stabilizing salt for high temperature use. The dry blended particulate composition is capable of significantly improving rheological properties. It is useful for making hydraulic fracturing and other oilfield treatment fluids.

Abstract: Improved methods and compositions for stabilizing a subterranean formation containing water sensitive minerals are provided. The formation is contacted with a water soluble stabilizing compound that dissolves to form a divalent organic cation. The stabilizing compound inhibits the swelling and migration of clays and fines, thereby alleviating loss in permeability of the formation.

Abstract: A composition comprising: (a) 0.001% to 20% of at least one compound having: (i) at least one carbonyl-, thiocarbonyl- or imine-containing functional group which is not a carboxyl group; (ii) at least one polar group two to ten chemical bonds from a carbonyl, thiocarbonyl or imine carbon; and (iii) at least ten carbon atoms; and (b) crude oil.

Abstract: Disclosed are methods and related compositions for altering the physical and chemical properties of a substrate used in hydrocarbon exploitation, such as in downhole drilling operations. In a preferred embodiment a method involves formulating a fluid, tailored to the specific drilling conditions, that contains one or more inactivated enzymes. Preferably the enzyme is inactivated by encapsulation in a pH responsive material. After the fluid has been introduced into the well bore, one or more triggering signals, such as a change in pH, is applied to the fluid that will activate or reactivate the inactivated enzyme, preferably by causing it to be released by the encapsulation material. The reactivated enzyme is capable of selectively acting upon a substrate located downhole to bring about the desired change in the chemical or physical properties of the substrate.

Abstract: The present invention relates to well bore stabilization and, more particularly, to treatment fluids that may reduce the tendency of shales to swell and associated methods. In some embodiments, the present invention provides a method of stabilizing a subterranean formation that comprises a shale, the method comprising contacting the subterranean formation that comprises the shale with a treatment fluid, the treatment fluid comprising a base fluid, and a hydrophobically modified polymer. In other embodiments, the treatment fluids comprise a base fluid and a hydrophilically modified polymer. In yet other embodiments, the present invention provides shale-inhibiting components, treatment fluids, and methods of reducing the tendency of shale to swell when exposed to a treatment fluid.

Abstract: A glycol-based well stimulation fluid and a process for recycling a glycol-based well stimulation fluid, comprising the steps of filtration and heating.

Abstract: Processes to recover brine from drilling fluids and other fluids is described. One process involves filtering drilling fluids or other well servicing fluids using a rotary vacuum filter to recover at least a portion of the brine in the drilling fluid. Well servicing fluids, including drilling fluids, containing recycled brine are further described.

Abstract: A monovalent cation containing well fluid composed of an aqueous brine containing at least 0.6 equivalents per liter of a water soluble monovalent cation salt, is substantially free of divalent cations, and an amount of a starch derivative selected such that the well fluid has the following characteristics: (a) a low shear rate viscosity greater than about 5,000 centipoise; (b) a high shear rate viscosity at 511 sec−1 in the range from about 15 to about 70 centipoise measured at 120° F. is described. The fluid may be formulated to be substantially free of xanthan gums and preferably has less than 0.25 lb/bbl of xanthan gum.

Abstract: Viscous well treating fluids and methods of treating subterranean zones penetrated by well bores are provided. The viscous fluids are basically comprised of water, a gelling agent and a delayed viscosity breaker comprising pentanedione peroxide.

Abstract: A method of cement lining a wellbore to enable a fixed sensor internal of the lining to sense characteristics of the external formations surrounding the wellbore, wherein, at the region of the sensor position, means are utilised before completion of setting of the cement to create, in use, a permanent fluid pressure connection through the cement lining between the external formation and the sensor.

Abstract: The present invention provides an electropositive and water-based production well treating fluid system. The production well treating fluid system can be made to exhibit electropositivity by using a cationic viscosifier meanwhile matched with a cationic fluid loss additive and optionally matched with a mud-building agent, electrical stabilizing agent, colloid-stabilizing agent, lubricant, oil layer protective agent and/or weighting agent. Such kind of electropositive production well treating fluid can solve better the contradiction between “treating fluid stability” and “bore hole stability”, and has features in strong ability of inhibiting the dispersion of clay, good effect of protecting oil-gas reservoir, fast drilling speed, regular shape of bore hole and good resistance to salt. The present invention relates further to a method of preparing said production well treating fluid system and use of the drilling fluid and well completion fluid in petroleum drilling and well completion.

Abstract: The present invention provides methods and compositions for sealing subterranean zones containing oil to prevent the uncontrolled flow of fluids into or from the zones. The compositions basically comprise water, a phosphonic acid ester, a multivalent metal ion releasing compound and an organophilic clay.

Abstract: The present invention relates to subterranean cementing operations, and more particularly, to cement compositions comprising elastic particles and having improved mechanical properties, and methods of using such compositions in subterranean cementing operations. An example of a method of the present invention comprises the steps of: providing a cement composition comprising a base fluid, a hydraulic cement, and a portion of elastic particles; placing the cement composition in a well bore in a subterranean formation; permitting a portion of the cement composition to enter openings in a region of the subterranean formation in fluid communication with the well bore; and permitting the portion of the cement composition to seal the openings off from the well bore. Another example of a method of the present invention comprises the step of adding a portion of elastic particles to a cement composition.

Abstract: Compositions and methods for determining the source of treatment fluids being produced from a production formation having multiple zones by introducing a treatment composition having a tracking material into a zone in the subterranean formation, and detecting the tracking material in treatment composition that flows back from the subterranean formation.

Abstract: Method is provided for increasing the productivity of gas wells producing from reservoirs where retrograde condensation occurs around the wells. An oil-wetting surfactant is injected in a solvent to oil wet the formation for a selected distance around a well or a hydraulic fracture intersecting the well. A pre-flush liquid, such as carbon dioxide, alcohol or similar products and mixtures thereof, may be used to reduce water saturation before injection of the surfactant. The method may also be applied to increase the productivity of oil wells producing from reservoirs where breakout of solution gas occurs near the well.

Abstract: A process for stimulating a formation is disclosed wherein a diverting fluid is used to divert an acid treatment package from a high permeability or damaged portion of a formation to a low permeability or undamaged portion of a formation. The fluid, which preferably forms vesicles, comprises at least one surfactant, at least one quaternary amine polyelectrolyte, water, and a non-aqueous solvent.

Abstract: Polyester compositions and methods of producing and using same are provided. The polyester compositions at least include an anionic diacid monomer or diester monomer thereof and a polyether. The polyester compositions of the present invention can be effectively utilized, for example, to treat crude oil during production and refinery processing.

Abstract: Cement compositions containing an expandable material are disclosed. The compositions are suitable for use in oil and gas wells. An example of such an expandable material is a polymer encapsulated chemical that expands upon heating. Examples of cement compositions containing polymer encapsulated isobutane or isopentane are disclosed. The use of cement compositions containing an expandable material can reduce the formation of micro-annulus or other deleterious physical properties in the set cement.

Abstract: Aluminum carboxylate drag reducing agents are described herein. These materials are useful to reduce drag in hydrocarbon fluids and multiphase fluids of hydrocarbon(s) and water. No injection probes or other special equipment is expected to be required to introduce the drag reducing agent into the liquid stream. The drag reducing additives of the invention are not subject to shear degradation and do not cause undesirable changes in the emulsion or fluid quality of the fluid being treated, or undesirable foaming. In one non-limiting embodiment, an aluminum monocarboxylate is reacted with at least one carboxylic acid in situ. In another non-limiting embodiment, the aluminum carboxylate is introduced as a dispersion in a solvent such as paraffin oil. The drag reducing additives include aluminum dicarboxylates such as aluminum dioctoate, aluminum distearate, aluminum octoateoleate, aluminum octoatestearate, aluminum stearateoleate, hydroxyaluminum bis(2-ethylhexanoate) and mixtures thereof.

Abstract: Improved methods of forming fractures containing resilient proppant particle packs which prevent the production of sand and fines with produced fluids and prevent proppant flow-back in a subterranean zone penetrated by a well bore are provided. As the fractures are formed, a liquid hardenable resin component is mixed with a liquid hardening agent component and a liquid rubber component to form a hardenable resin composition. The hardenable resin composition is coated onto dry proppant particles which are suspended in the fracturing fluid and placed in the fractures. The hardenable resin composition on the resin composition coated proppant particles is allowed to harden and consolidate the proppant particles into high strength resilient permeable packs.

Abstract: The invention relates to surfactant based viscoelastic fluids for enhancing the productivity of a hydrocarbon-bearing formations, such as oil wells. The viscoelastic fluids of the invention have particular applicability in acid fracturing of subterranean formations surrounding oil and gas wells. The viscoelastic fluid contains an inorganic acid and at least one C10 to C24 alkyl trialkyl quaternary ammonium aromatic salt such as quaternary ammonium salicylate or phthalate. An anionic surfactant may also be present in the viscoelastic fluid. The addition of the C10 to C24 alkyl trialkyl quaternary ammonium aromatic salt to the inorganic acid causes gellation of the acid.

Abstract: Disclosed is a method for introducing additives into an oil, gas, or water injection well or pipeline in solid form at a location other than at the bottom. The method is practiced using pellets having a density sufficient to suspend the pellet at a top phase, bottom phase or at the interface of two phases of fluid within a wellbore. The pellets are prepared from a pellet matrix, such as an ethoxylated wax, and a weighting agent as well as an additive. By varying the amount of weighting agent, the density of the pellet can be varied to suspend it at a desired point to for a time sufficient to deliver the additive to the desired point within the wellbore.

Abstract: A composition and method are given for self-destructive fluid loss additives and filter cakes in wellbores and subterranean formations. The fluid loss additives and filter cakes are formed from a mixture of particulate solid acid-precursors, such as a polylactic acid or a polyglycolic acid, and particulate solid acid-reactive materials, such as magnesium oxide or calcium carbonate. In the presence of water, the solid acid-precursors hydrolyze and dissolve, generating acids that then dissolve the solid acid-reactive materials. The composition is used in oilfield treatments such as drilling, completion and stimulation where it disappears when it is no longer needed without the use of mechanical means or injection of additional fluids.

Abstract: The use of high flash point, low vapor pressure compositions for injection into, and coating of, gas and oil wells and surrounding underground hydrocarbon bearing formations and processing equipment for the purpose of removing scale, paraffins, tars, and other viscous constituents. Treatment results in increased flow of gas and/or oil and decreased adhesion of soil and scale in all aspects of oil and gas recovery, including hydrocarbon bearing formations, casings, lines and pumping equipment. The composition contains about 40 to 99 wt. % of a fatty acid alkyl ester blend and about 1 to 25 wt. % of at least one lower alkyl glycol ether.

Abstract: A method of depolymerizing galactomannan-type polysaccharide polymers and xanthan, preferably galactomannans, to a pre-selected lower molecular weight by irradiation with high energy electron beams. The preferred galactomannans for treatment according to this method are guar gum, guar splits and hydroxypropyl guar. In a preferred embodiment the guar gum is depolymerized preferably to a molecular weight of about 150,000 Daltons to about 200,000 Daltons. The depolymerized guar has a polydispersity of less than about 3.0 and is useful in oil well fracturing to enhance oil production.

Abstract: A controlled-gelation aqueous solution is proposed. The solution contains a hydrophobically-aggregating gelling agent, and an effective amount of an inhibitor which suppresses hydrophobic aggregation of the gelling agent. The inhibitor is soluble in water so that when the controlled-gelation aqueous solution contacts aqueous media the inhibitor disperses and gelation occurs. However, the inhibitor is substantially insoluble in hydrocarbons so that when the controlled-gelation aqueous solution contacts hydrocarbon media the inhibitor continues to suppress said hydrophobic aggregation and gelation is suppressed. The solution may be used to control the flow of water into oil wells, making it possible to reduce the water cut.

Abstract: A method is provided for blocking high permeability regions in subterranean geological formations, using a reinforced swelling clay gel. A reinforced clay slurry is prepared by mixing swelling clay, such as bentonite, an aqueous solution containing the salt of certain cations, which inhibit clay swelling, and a reinforcing agent. The cations K+, Ca2+, Mg2+, Cs2+, Fe2+, Al3+ and NR4+, where each R can independently be H, CH3, C6H5, or CH2CH3, and combinations thereof, among others, are clay swelling inhibitors. The reinforcing agent is non-swelling particles, including, without limitation, particles of produced sand, silica sand, sandy or silty soil, crushed rock, minerals, mine tailings, and combinations thereof. The reinforced clay slurry is introduced into a geological formation, where it preferentially enters high permeability regions.

Abstract: A viscoelastic wellbore treatment fluid comprises an effective amount of an oligomeric surfactant for controlling the viscoelasticity of the fluid.

Abstract: The invention provides an aqueous suspension/concentrate of a sparingly soluble borate, preferably as disclosed in Mondshine U.S. Pat. No. 4,619,776, which is effective in crosslinking aqueous solutions of a water soluble, borate-crosslinkable polymer, preferably guar gum and derivatives thereof. The aqueous suspension/concentrate comprises a saturated aqueous solution of a sparingly soluble borate, a suspension agent, suspended particles of a sparingly soluble borate, and optionally a stabilizing agent, wherein the saturated solution of the sparingly soluble borate is prepared prior to the particles of the sparingly soluble borate being suspended therein. The preferred suspension agent is a palygorskite clay such as attapulgite and sepiolite. The invention further provides a method of hydraulically fracturing a formation with the aqueous borate suspension/concentrate.

Abstract: Disclosed are paraffin inhibitors prepared by admixing a polymer having the characteristic of inhibiting paraffin crystalline growth in formation fluid from oil and gas wells with a first solvent selected from the weak to moderate wax solvents and a second solvent selected from the strong wax solvents. Exemplary weak to moderate wax solvents include benzene, toluene, xylene, ethyl benzene, propyl benzene, trimethyl benzene and mixtures thereof. Exemplary strong wax solvents include cyclopentane, cyclohexane, carbon disulfide, decalin and mixtures thereof. The solvent system disclosed has desirably better solubility with the polymers, even at reduced temperatures, than either solvent alone.

Abstract: The present invention provides a cement composition and a process for using the cement composition to inhibit gas migration from a subterranean zone into the cement. The process comprises displacing a gelling additive, preferably comprised within a cement composition, into a well bore such that the gelling additive passes into the subterranean zone, and allowing the gelling additive to form a crosslinked gel in the subterranean zone to inhibit gas migration from the subterranean zone. The crosslinked gel acts as a barrier to gas in the subterranean zone and thereby inhibits the gas from passing into the cement and forming flow channels therein before the cement can set.

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: An apparatus (200) and method for repairing an opening (130) in a wellbore casing (110). The apparatus (200) and method couple a floating tubular (250) member in opposing relation to the opening (130) in the wellbore casing (110).

Abstract: For hydraulic fracturing treatment to increase productivity of subterranean hydrocarbon bearing formation, a hydraulic fracturing additive including a dry mixture of water soluble crosslinkable polymer, a crosslinking agent, and a filter aid which is preferably diatomaceous earth. The method of forming a hydraulic fracturing fluid includes contacting the additive with water or an aqueous solution, with a method of hydraulically fracturing the formation further including the step of injecting the fluid into the wellbore.