Abstract: A variety of methods and compositions are disclosed, including, in one embodiment, A friction reducer comprising: a continuous phase comprising a base oil and a secondary oil, wherein the secondary oil is different than the base oil; a discontinuous phase dispersed in the continuation phase, wherein the discontinuous phase comprises water and a water-soluble polymer; and an emulsifying surfactant.

Abstract: Provided is an aqueous acidic emulsifying composition comprising a specific amine and a polymerized fatty acid, a process for preparing the composition, a process for preparing bituminous emulsion and to the use of the composition for spreading bitumen.

Abstract: A high strength engineered reactive composite that includes a reactive core. These reactive composites are useful for oil and gas completions and well stimulation processes, enhanced oil and gas recovery operations, as well as in defensive and mining applications requiring high energy density and good mechanical properties.

Abstract: Methods and systems for designing, monitoring, and/or performing acidizing treatments in subterranean formations are provided. A method comprises: determining a wellbore pressure and a fluid flow distribution for an acidizing fluid introduced into an interval of a well bore penetrating a portion of a subterranean formation; determining an optimum interstitial velocity for the acidizing fluid in the subterranean formation and an interstitial velocity of the acidizing fluid at a tip of a wormhole in the subterranean formation at a first flow rate at each of a plurality of depths; and if the interstitial velocity of the acidizing fluid at the tip of the wormhole is less than the optimum interstitial velocity at one or more of the plurality of depths, identifying a second flow rate for introducing the acidizing fluid into the interval of the well bore that is greater than the first flow rate.

Abstract: The disclosure relates to a method of delaying viscosification of a well treatment fluid within a well or within a subterranean formation penetrated by a well by introducing into the well a hydratable viscosifying agent of particulates having a minimum of 40% retention on a 60 mesh screen and a minimum of 1% retention on a 20 mesh screen.

Abstract: A composition useful for crosslinking phosphate esters in hydrocarbon gels used in formation fracturing performs especially well in cold temperatures, such as temperatures lower than (?)20° C. Methods of making the crosslinking composition and the gel are described; also methods of fracturing subterranean formations. Specific forms of ferric sulfate and ferric ammonium citrate are useful as ingredients of the crosslinking composition.

Abstract: A method of fracturing a subterranean formation comprising at least in part shale formation, comprises providing a carrier fluid; providing a particulate blend including a first amount of particulates having a first average particle size between about 100 and 2000 microns and a second amount of particulates having a second average particle size between about three and twenty times smaller than the first average particle size, such that a packed volume fraction of the particulate blend exceeds 0.75; combining the carrier fluid and the particulate blend into a fracturing slurry; fracturing the formation with the fracturing slurry to create at least a fracture; and removing the second amount of particulates from the fracture.

Abstract: Methods that include a method comprising providing a hydrocarbon-acid emulsion composition that comprises an acid phase, a hydrocarbon blend phase, and an emulsifying agent; and placing the hydrocarbon-acid emulsion composition in a subterranean formation. In some embodiments, the hydrocarbon blend phase comprises at least about 65% hydrocarbons having from six carbons (C6) through eleven carbons (C11). In other embodiments, the hydrocarbon blend phase has a flash point greater than about 100° F. Additional methods are also provided.

Abstract: A composition useful for crosslinking phosphate esters in hydrocarbon gels used in formation fracturing performs especially well in cold temperatures, such as temperatures lower than (?)20° C. Methods of making the crosslinking composition and the gel are described; also methods of fracturing subterranean formations. Specific forms of ferric sulfate and ferric ammonium citrate are useful as ingredients of the crosslinking composition.

Abstract: A method of fracturing a subterranean formation comprising at least in part shale formation, comprises providing a carrier fluid; providing a particulate blend including a first amount of particulates having a first average particle size between about 100 and 2000 microns and a second amount of particulates having a second average particle size between about three and twenty times smaller than the first average particle size, such that a packed volume fraction of the particulate blend exceeds 0.75; combining the carrier fluid and the particulate blend into a fracturing slurry; fracturing the formation with the fracturing slurry to create at least a fracture; and removing the second amount of particulates from the fracture.

Abstract: The present invention is directed to novel additives packages, to fluid compositions including the additives, to methods of using the fluid compositions and the additives package, to methods of recovering hydrocarbons, and to petroleum products made from hydrocarbons derived from these methods. The novel additives packages may be used in a fluid composition for fracturing a subterranean. The additives package of the present invention include one or more gelling agents; one or more cross-linking agent; and one or more high temperature stabilizers; wherein the additives package further comprises one or more ingredients selected from the group consisting of a clay stabilizer, a metallic base, a cross-link retarder, and a gel breaker, and any combination thereof; and wherein the additives package optionally includes a diluent.

Abstract: A process is disclosed for treating an underground formation, which process comprises: (a) introducing into the underground formation a micellar dispersion comprising water, one or more organic acid precursors, one or more surfactants and, optionally, one or more salts, co-surfactants and/or organic liquids that are not organic acid precursors; and (b) allowing (i) the micellar dispersion to solubilize hydrocarbons, emulsions or water blocks present in the underground formation, and (ii) at least a portion of the organic acid precursor to hydrolyze in-situ to produce sufficient organic acid to substantively dissolve acid soluble material present in or adjacent to filter cakes or other damage in the underground formation.

Abstract: A method of treating a subterranean formation penetrated by a wellbore of a well having iron-containing components is carried out by introducing a treatment fluid into the wellbore of the well. The treatment fluid is formed from an aqueous solution, a mineral acid, a viscoelastic surfactant gelling agent and corrosion inhibitor system containing at least one of an alkyl, alkenyl, alicyclic or aromatic substituted aliphatic ketone and aliphatic or aromatic aldehyde. The treatment fluid is substantially free of any formic acid or precursor formic acid. In certain embodiments, the corrosion inhibitor system comprises a mixture of at least one of an alkenyl phenone or ?,?-unsaturated aldehyde, an unsaturated ketone or unsaturated aldehyde other than the alkenyl phenone and ?,?-unsaturated aldehyde, a dispersing agent, an extender and an alcohol solvent. A corrosion inhibitor intensifier may also be used in certain embodiments, which may include a mixture of cuprous iodide and cuprous chloride.

Abstract: A composition and method for improving the fluid efficiency of many oilfield treatments is given. The composition is a solid additive, in a viscosified fluid, in a size range small enough that it enters formation pores; it optionally bridges there to form an internal filter cake, and then decomposes to provide a breaker for the viscosifying system for the fluid. Examples of suitable additives include waxes, polyesters, polycarbonates, polyacetals, polymelamines, polyvinyl chlorides, and polyvinyl acetates. Degradation of the additive may be accelerated or delayed.

Abstract: A system includes a wellbore in fluid communication with a formation of interest and a fracturing slurry include a carrier fluid with a low amount of a viscosifier, an amount of proppant including a first average particle size between about 200 and 2000 ?m, an amount particulates including a second average particle size between about three and ten times smaller than the first average particle size, and a third amount of particulates having a third average particle size smaller than the second average particle size. A sum of all of the particulates in the fracturing slurry exceed about 16 pounds per gallon of the carrier fluid. They system further includes a pumping device that creates a propped fracture in the formation of interest with the fracturing slurry, and a removal agent that removes the second amount of particulates and/or the third amount of particulates from the propped fracture.

Abstract: A composition and method for improving the fluid efficiency of many oilfield treatments is given. The composition is a solid additive, in a viscosified fluid, in a size range small enough that it enters formation pores; it optionally bridges there to form an internal filter cake, and then decomposes to provide a breaker for the viscosifying system for the fluid. Examples of suitable additives include waxes, polyesters, polycarbonates, polyacetals, polymelamines, polyvinyl chlorides, and polyvinyl acetates. Degradation of the additive may be accelerated or delayed.

Abstract: Degradable polylactic or polyhydroxyalkanoate polymers may be used to viscosify aqueous fluids for use in wells. Sand control screen or liner can be coated with a solid degradable polymer during placement in a well. Mechanical changes or flow changes in a well can be caused by solid degradable polymer that changes physical properties after it is placed in a well. Parts of devices or entire devices can be made of solid degradable polymer that converts to a fluid after selected times in an aqueous environment in a well.

Abstract: An improved method and fracturing fluid for hydraulic fracturing of a subterranean formation, the fracturing fluid including a surfactant, a water soluble or dispersible anionic organic salt, an acid and a low molecular weight organic solvent.

Abstract: Propped fractures in formations from which fluids are produced are described that have wormholes extending out into the formations from the faces of the fractures at locations distant from boreholes. Methods are given for creating such propped fractures having wormholes in which either a closed propped fracture is formed and then the wormholes are formed, or the entire fracture and channel system is formed before the closure occurs.

Abstract: An acid fracturing method is provided in which the acid is generated in the fracture by hydrolysis of a solid acid-precursor selected from one or more than one of lactide, glycolide, polylactic acid, polyglycolic acid, a copolymer of polylactic acid and polyglycolic acid, a copolymer of glycolic acid with other hydroxy-, carboxylic acid-, or hydroxycarboxylic acid-containing moieties, and a copolymer of lactic acid with other hydroxy-, carboxylic acid or hydroxycarboxylic acid-containing moieties. The solid acid-precursor may be mixed with a solid acid-reactive material to accelerate the hydrolysis and/or coated to slow the hydrolysis. Water-soluble liquid compounds are also given that accelerate the hydrolysis. The method ensures that the acid contacts fracture faces far from the wellbore.

Abstract: A method for removing or dissolving calcareous materials in a subterranean formation or in a wellbore consists of two basic steps. In the first step, an aqueous acid solution is injected into the formation or wellbore. The aqueous acid solution contains between from about 15 to about 99 weight percent of an organic acid selected from formic acid, acetic acid or a mixture of formic acid and acetic acid. Water or brine is then injected into the formation or wellbore. The amount of water or brine injected into the formation or wellbore is an amount sufficient to reduce the concentration of organic acid in the formation or wellbore to no greater than 10 weight percent.

Abstract: Disclosed is a copolymer useful for preparing acid gels comprising a copolymer having a copolymer backbone, the copolymer having a general formula: wherein: (a) A is an H or other terminating group; (b) R1 is an OH or NH2; (c) R2 is an O or NH; (d) Z is an integer having a value of from 1 to 4; (e) X and Y are present in a ratio (X:Y) of from 3:2 to 4:1; (f) structures I and II are present as blocks or randomly distributed along the copolymer backbone; and wherein the copolymer has a molecular weight of from about 1,000,000 to about 10,000,000.

Abstract: Stimulation, particularly fracturing or acidising, of hydrocarbon wells having bores leading to hydrocarbon bearing uses a fluid including a continuous phase of or including a compound of the formula (1): (R2)p—Ph—(CH2)m—COO—(AO)n—R1 where R1, AO, n, m, Ph, R2 and p having defined meanings and particularly where the esters are alkyl or alkenyl benzoate esters. These esters are beneficial by having a range of viscosities, especially extending to low viscosities, and attractive toxicological and environmental profiles for use in well stimulation.

Abstract: An improved method and fracturing fluid for hydraulic fracturing of a subterranean formation, the fracturing fluid comprising a surfactant, a water soluble or dispersible anionic organic salt, an acid and a low molecular weight organic solvent.

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: The improved recovery of hydrocarbons from subterranean formations by hydraulically fracturing a subterranean formation is accomplished. Fracturing fluids using a viscosifying surfactant fluid containing viscosifying micelles, for example, wormlike micelles, are useful to improve recovery of hydrocarbons and limit the loss of fracturing fluid into the formation fracture face. The invention further relates to novel fracturing and acidizing methods useful for increasing hydrocarbon production, limiting water production, resisting fracturing fluid loss into the subterranean formation, and reducing the equipment requirements in mixing and pumping fracturing fluid. The action of viscosifying micelles of surfactant in aqueous zones of the subterranean formation diverts fracturing fluid or acid from the aqueous zones to the hydrocarbon-bearing zones and also facilitates the flowback of increased amounts of hydrocarbons once a fractured well is placed back on production.

Abstract: The present invention provides environmentally safe foamed acidizing fluids for acidizing subterranean zones, additives for foaming and stabilizing foamed acidizing fluids and methods of acidizing subterranean zones. The foamed acidizing fluids are basically comprised of an aqueous acid solution, sufficient gas to form a foam and an effective amount of an additive for foaming and stabilizing the aqueous acid solution comprised of hydrolyzed keratin.

Abstract: The improved recovery of hydrocarbons from subterranean formations by fracturing and matrix acidizing a subterranean formation is accomplished. Well treatment fluids having a viscoelastic surfactant fluid containing worm like micelles are useful to improve recovery of hydrocarbons and limit the loss of fracturing fluid into the formation fracture face. The viscolastic surfactant-based fracturing fluids of the present Invention are stable across a wide pH spectrum, allowing them to be used for fracturing treatments at low pH, as well as matrix acidizing treatments. In addition, the stability of these fluids is enhanced in the presence of organic anions. Two-stage fracturing treatments comprised of a viscoelastic surfactant-based fracturing fluid and a polymer-based system, wherein the two fluids are either blended or pumped into the formation sequentially (the polymer last) are also presented.

Abstract: The invention relates to iron control in an acid medium for forestalling the formation of precipitates known as “sludges” (asphaltic products) in contact with certain crude oils. Use is made of compounds comprising a mercaptan function, and, in combination, a selection of catalysts. Application to acid treatments for oil, gas, water, geothermal and analogous wells, as well as to industrial cleaning.

Abstract: A composition and method for acidizing a formation in the presence of ferric ion, free sulfur and/or sulfides is disclosed. The composition employs a ferric ion reducing agent and a sulfide reactant separately or in combination. The ferric ion reducing agent is a thioalkyl acid. The sulfide reactant compounds include &agr;-diketones and saturated and &agr;-unsaturated cyclic ketones. In another aspect, the reducing activity of the thioalkyl acid is accelerated by the presence of a catalytic quantity of a compound or mixture of compounds which yield in acid solution cuprous ion, cupric ion or combinations thereof with iodide ion.

Abstract: A method of fracturing a subterranean formation, in which subterranean formation being in fluid communication with the surface includes creating a fracture in said subterranean formation, said fracture having more than one fracture faces; and injecting into said fracture an encapsulated formation etching agent, wherein said encapsulated formation etching agent includes a formation etching agent and an encapsulating agent and wherein said formation etching agent etches the fracture faces of the fracture so as to form a flow channel in said formation. The formation etching agent may be selected from mineral acids and mixtures thereof, organic acids and mixtures thereof, mineral acids and mixtures of mineral acids mixed with gelling agent, organic acids and mixtures of organic acids mixed with gelling agent, water soluble hydroxides and mixtures of water soluble hydroxides, and water soluble hydroxides and mixtures of water soluble hydroxides mixed with gelling agent.

Abstract: A method of fracturing a subterranean formation which surrounds a well bore comprises the steps of providing a fracturing fluid, and injecting the fracturing fluid into the well bore at a pressure sufficient to form fractures in the subterranean formation which surrounds the well bore. The pressure is then released from the fracturing fluid, after which the fluid may be removed from the well and the well placed into production. The fracturing fluid comprises an aqueous liquid, a polysaccharide soluble or dispersible in the aqueous liquid in an amount sufficient to increase the viscosity of the aqueous liquid, an enzyme breaker which degrades the polysaccharide at a temperature above 180° F. Fracturing fluid compositions and enzyme breaker systems useful for carrying out the invention are also disclosed.

Abstract: A crosslinked acid gel comprising an emulsion polymer and an external activator is provided. Methods for acid fracturing subterranean formations using the crosslinked acid gel are also provided.

Abstract: A crosslinked acid gel comprising an emulsion polymer and an external activator is provided. Methods for acid fracturing subterranean formations using the crosslinked acid gel are also provided.

Abstract: Hydrocarbon fracturing fluids are made by combining organic phosphate esters with polyvalent metal salts in hydrocarbon carriers to form gels; breaking of the gel is retarded or otherwise controlled over a wide range of water concentrations, through the use of slowly soluble alkaline earth metal compounds, preferably hard burned magnesium oxide, which may be added along with the gel component. The slowly soluble alkaline earth metal compound is employed together with an oily acid breaker retarding agent such as tall oil.

Abstract: The invention provides: (1) a process to enhance the removal of solids such as clays, clay-like solids, and shale solids-drill solids-from the surface of a borehole, the solids being deposited from well drilling, completion, or workover fluids during well servicing operations; and (2) a process to enhance the removal of such solids from screens or other sand control devices present in a borehole. The process comprises contacting the solids with an acidic soak solution containing a polyglycol or mono ether derivative thereof and thereafter contacting the surface of the borehole with a wash solution to remove the solids from the borehole.

Abstract: The present invention provides microemulsion surfactant additives for use in aqueous well treating fluids to prevent the formation of stable emulsions and sludge when the aqueous treating fluids contact hydrocarbons. The additives are basically comprised of a solvent, a co-solvent, water, an aqueous liquid-hydrocarbon liquid de-emulsifying surfactant and a liquid hydrocarbon antisludging surfactant. Aqueous compositions including the additives and methods of treating subterranean formations or zones containing hydrocarbons using the compositions are also provided.

Abstract: The present invention provides improved quaternary ammonium compounds useful as metal corrosion inhibitors in aqueous acid solutions, methods of preparing the compounds, metal corrosion inhibited aqueous acid solutions containing the compounds and methods of protecting metal surfaces from acid corrosion using the compounds. The compounds are prepared by contacting the still bottoms residue produced in the distillation of quinoline from coal tar with oxygen to oligomerize aromatic amines contained therein and then reacting the oligomerized amines with a benzylhalide.

Abstract: A high internal phase ratio water-in-oil emulsion containing an emulsifier comprising a block or graft copolymer the general formula (A-COO).sub.mB or a reaction product of a polyalk(en)yl succinic anhydride and a polar compound having at least one hydroxyl or amino group demonstrates surprisingly low pumping friction pressure losses, high temperature stability and excellent proppant carrying capacity for use as a fracturing fluid in the hydraulic fracturing of subterranean formation.

Abstract: This invention relates to anionic compositions, containing an alkyl aryl sulfonic acid or salt thereof, a nonethoxylated glycol and an acetylenic alcohol in an alkyl alcohol solvent, that have proved effective for controlling sludge and emulsion formation during acid stimulation and treatment of hydrocarbon wells.

Abstract: Disclosed is an improvement in a method for propping a fracture adjacent a wellbore formed by injecting in said fracture a carrier fluid containing proppant coated with a curable resin which improvement comprises:a) using proppant coated with a resin fluid containing a polymerizable oligomer of furfuryl alcohol resin, a catalyst comprising an oil soluble, slightly water soluble organic acid and an ester of a weak organic acid to consume water produced by the polymerization of resin;b) using as a carrier an aqueous saline fluid comprising water which is 70% to 100% saturated with sodium chloride,c) suspending said resin-coated proppant in the carrier fluid, forming a fluid mixture of resin-coated proppant and carrier fluid; and injecting said mixture into said fracture, wherein the timing of the addition of the catalyst can be varied.

Abstract: Subterranean oil-bearing formations are treated with aqueous acid solutions which include an effective amount of an alkoxylated alkyl substituted phenol sulfonate which exhibits both antisludge and demulsification properties.

Abstract: A method of stimulating production in sandstone formations of oil and gas wells is achieved by using an acid system which slowly dissolves the silicate and clay formations of the sandstone to increase its permeability. The acid system uses phosphonate compounds, including phosphonate acids and the salts and esters thereof, in combination with hydrofluoric acid. The hydrofluoric acid may be provided by hydrolyzing ammonium bifluoride or hydrofluoric acid itself. The phosphonate compounds of the acid systems retard the rate at which the hydrofluoric acid reacts with the clays while enhancing the reaction rate with silica, which comprises the bulk of sandstone formations. This allows more penetration of the formation immediately adjacent to the wellbore. The phosphonate materials also improve the dispersion and suspension properties of the treating solution with silts and fines and improves the complexing capacity of the acids with silicate and alumni complexes.

Abstract: A particulate gel breaker for the controlled reduction in viscosity of aqueous acid compositions used in fracture acidizing of subterranean formations, such as in oil and gas wells, is formed for use with crosslinked polymer gels which are crosslinked with organometallic compounds, such as titanium or zirconium. The gel breaker is composed of particles containing complexing materials such as fluoride, phosphate, sulfate anions and multi-carboxylated compounds, which are capable of complexing with the organometallic crosslinking compounds of the gel. The particles are coated with a water insoluble wood resin coating which reduces the rate of release of the complexing materials of the particles so that the viscosity of the gel is reduced at a retarded rate. The gel can thus be introduced into the well at a sufficiently high viscosity for fracturing and to allow time for the acid to penetrate the formation before the acid is released.

Abstract: A method of gelling a guar or derivatized guar polymer solution utilized to perform a hydraulic fracturing operation includes the step of adjusting the pH of the guar or derivatized guar polymer solution to between about 8.5 and 12.5. After adjusting the pH, an anhydrous boron compound or a sparingly soluble borate suspended in a mineral spirits-resin solution or an oil-resin solution is added to the guar or derivatized guar polymer solution. The guar or derivatized guar polymer solution and the anhydrous boron compound or the sparingly soluble borate solution suspended in the mineral spirits-resin solution or the oil-resin solution is then pumped into a subterranean formation under sufficient pressure to cause a fracture in the formation rock.