Abstract: A foam drive method for enhancing oil recovery efficiently is initiated by injecting into a subterranean oil-bearing formation, an aqueous polymer solution as a preceding-slug. This is followed by periodically injecting simultaneously or alternately a non-condensible gas and an aqueous solution of foaming composition to form a combined foam under ground or periodically injecting the combined foam formed beforehand by the gas and said aqueous solution above ground. The aqueous solution of foaming composition comprises an alkali, a surfactant and a polymer. Thereafter, an aqueous polymer solution used as a protecting-slug is injected into the formation; followed by continuing water-flooding.

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 fracturing fluids, additives for foaming and stabilizing foamed fracturing fluids and methods of fracturing subterranean zones. The foamed fracturing fluids of this invention are basically comprised of water, a gelling agent for forming the water into gelled water and increasing the viscosity thereof, sufficient gas to form a foam, and an effective amount of an additive for foaming and stabilizing the gelled water comprised of hydrolyzed keratin.

Abstract: Improved methods of cementing in subterranean zones penetrated by well bores are provided. The methods are basically comprised of the steps of preparing a cement composition comprised of a hydraulic cement, a biodegradable, substantially non-dispersing set retarder of low anionic character comprised of polysuccinimide and sufficient water to form a slurry, placing said cement composition in said subterranean zone and allowing said cement composition to set into a solid mass therein.

Abstract: The present invention provides improved foamed well cement slurries, additives and methods. The foamed well cement slurries are basically comprised of a hydraulic cement, sufficient water to form a pumpable slurry, sufficient gas to form a foam and an effective amount of an additive for foaming the slurry comprised of hydrolyzed keratin.

Abstract: Methods and compositions for forming permeable cement sand screens in well bores are provided. The compositions are basically comprised of a hydraulic cement, an acid soluble particulate solid, a liquid hydrocarbon solvent soluble particulate solid, a particulate cross-linked gel containing an internal breaker which after time causes the gel to break into a liquid, water present in an amount sufficient to form a slurry, a gas present in an amount sufficient to form a foam and a mixture of foaming and foamed stabilizing surfactants.

Abstract: The present invention provides improved methods of cementing casing strings in deep water offshore formations penetrated by well bores. The methods are basically comprised of the steps of preparing a cement composition comprised of hydraulic cement, water, gas, a mixture of foaming and foam stabilizing surfactants, a cement early strength accelerator and a mildly set retarding cement dispersing agent, placing the cement composition in the annulus between the casing string and the well bore and allowing the cement composition to set into a hard impermeable mass.

Abstract: Improved methods of completing subterranean producing zones containing unconsolidated sands penetrated by well bores are provided. The methods are basically comprised of placing a sand screen in the zone, isolating the annulus between the sand screen and the well bore in the zone, introducing particulate solids and foam forming pellets or open cell foam pieces with or without particulate solids and foam forming pellets into the annulus between the sand screen and the well bore to thereby form a formation sand screening permeable pack in the annulus. When utilized, the foam forming pellets are activated by heat or other means to form a foam which expands and solidifies in the pack thereby eliminating voids and strengthening the pack.

Abstract: A process for circulating an aqueous foam in a wellbore includes the steps of forming a foam from an aqueous composition having a determined pH value, injecting the foam into a well so that it circulates from the surface to the well bottom and then back from the well bottom to the surface, and then changing the pH value of the foam when it returns to the surface. The aqueous composition from which the foam is made includes at least one ionic surfactant whose charge does not practically depend on the pH value and a polyampholytic polymer whose global charge depends on the pH value. This composition gives the foam the property that when the pH of the foam is varied at the surface of the well, the charge of the polyampholytic polymer is modified and the foam becomes destabilized and breaks more readily.

Abstract: A process for insulating a tubing string placed in a pipe and through which a fluid circulates, the insulant being a non-rigid foam produced from a liquid solution and placed in the annular space defined by the outside of the tubing string and the walls of the pipe in which these tubings are placed. A production well (1) opens, in the lower part thereof, onto a producing rock containing a fluid to be extracted. Tubing (2) is placed in production well (1). A zone (3) represents the annulus defined between the outside (5) of the tubing string and the walls of well (1) in which the tubing string is placed. A tube for injecting a liquid and/or gaseous fluid (4) is placed in annulus (3) and a liquid and/or gaseous fluid injection nozzle (6) opens into zone (3).

Abstract: The present invention provides improved methods of cementing casing strings in deep water offshore formations penetrated by well bores. The methods are basically comprised of the steps of preparing a cement composition having a short transition time comprised of hydraulic cement, a water reducing additive, a dispersing additive, a compressive strength enhancing and set retarding additive, a set accelerating additive and water, placing the cement composition in the annulus between the casing string and the well bore and allowing the cement composition to set into a hard impermeable mass.

Abstract: The method for releasing the stuck pipe of the present invention uses a combination of components which oxidize the mud cake and generated gas bubbles to create an upward buoyancy for the oxidized mud cake. The spotting method of the present invention comprises adding to the borehole in the region of the stuck pipe: 1) an oxidizer which oxidizes the mud cake; and 2) at least one component which reacts in the borehole to generate a gas. Optionally, but preferably, the spotting method further uses a lubricant which is added to the borehole in the region of the stuck pipe. The lubricant acts to lubricate the oxidized parts of the mud cake. Also disclosed is a spotting fluid system including 1) an oxidizer which oxidizes the mud cake, 2) at least one component which reacts in the borehole to generate a gas, and, optionally a lubricant which acts to lubricate the oxidized parts of the mud cake.

Abstract: A CO2-foamable gelling composition and use of said composition for conformance control operations are described The gelling fluid comprises a decomposing agent to counteract the detrimental effect of CO2 on the gelling process.

Abstract: An improved method of cementing casing in a deep water offshore formation penetrated by a well bore comprising the steps of preparing a foamed cement composition comprised of calcium aluminate cement, a set accelerating additive, a thickening time increasing additive, water, a gas, and a mixture of foam forming and foam stabilizing surfactants; placing the cement composition in the annulus between the casing and well bore; and allowing the cement composition to set into a hard impermeable mass therein.

Abstract: Improved methods of cementing in a subterranean zone penetrated by a well bore are provided. The methods are basically comprised of the steps of preparing a foamed cement composition comprised of hydraulic cement, a non-dispersing set retarder, sufficient water to form a slurry, sufficient gas to foam the slurry and a foaming and foam stabilizing surfactant mixture present in an amount sufficient to facilitate the formation of the foam and stabilize the foamed cement composition.

Abstract: High strength foamed well cement compositions and methods of cementing subterranean zones penetrated by well bores are provided. The foamed well cement compositions are basically comprised of a hydraulic cement, hydrophilic fibers, water sufficient to form a pumpable slurry, a mixture of foaming and foam stabilizing surfactants and sufficient gas to foam the slurry.

Abstract: A well, such as a natural gas well, may be treated to increase production of gas by inserting into the tubing string a water soluble carrier containing a well treating chemical adapted to aerate fluids standing in the tubing string. The dissolvable carrier contains a compressed swab adapted, upon dissolution of the carrier, to expand to fill the diameter of the tubing string, and well treating chemicals adapted to aerate the standing fluid in the well above and below the swab. The presence of the aerating fluids in the well lighten the hydrostatic head, permitting a plug of fluid above the swab to be displaced from the well as the swab is urged upward due to pressure exerted on the swab by the formation and by the aerating effect of well treating chemicals released below the swab.

Abstract: Solid, slowly dispersible well treatment composites are provided which have a sufficiently high melting point to prevent melting of the composite in hot weather. The composites have a low solubility and high specific gravity compared to prior art treatment agents; thus the composites readily sink in well and pipeline fluids and slowly release treatment ingredients over time, depending on the downhole and pipeline conditions. The composites include a nonylphenol ethoxylate having at least about 50 moles of ethylene oxide per mole of nonylphenol and a fatty acid amide having from 14-20 carbon atoms. Preferably, the composites further include a weighting agent and active ingredients selected from the group consisting of corrosion inhibitors, scale inhibitors, bactericides, scale converters, foaming agents, and mixtures thereof. In one embodiment, the composites are spherical in shape and are passed through pipelines for maintenance and treatment of the pipelines.

Abstract: Methods of preventing the production of sand with fluids produced from a subterranean formation penetrated by a well bore are provided. The methods basically comprise the steps of preparing a resin composition which delayedly forms a hardened open cell foam capable of allowing the passage of well fluids therethrough while screening and preventing the passage of formation sand and then placing the resin composition adjacent to the formation by way of the well bore.

Abstract: Solid, slowly dispersible well treatment composites are provided which have a sufficiently high melting point to prevent melting of the composite in hot weather. The composites have a low solubility and high specific gravity compared to prior art treatment agents; thus the composites readily sink in well and pipeline fluids and slowly release treatment ingredients over time, depending on the downhole and pipeline conditions. The composites include a compound selected from the group consisting of nonylphenol ethoxylates having at least about 50 moles of ethylene oxide per mole of nonylphenol, fatty acid amides having from 14-20 carbon atoms, and mixtures thereof. Preferably, the composites further include a weighting agent and active ingredients selected from the group consisting of corrosion inhibitors, scale inhibitors, bactericides, scale converters, foaming agents, and mixtures thereof.

Abstract: Aphron-containing oil based well drilling and servicing fluids are disclosed which seal microfractures and the like during drilling and well servicing operations, thus decreasing the volume of fluid lost to the formations contacted by the fluids.. The fluids comprise an oleaginous liquid as the continuous phase, a viscosifier which imparts a low shear rate viscosity to the fluids of at least 10,000 centipoise, an aphron-generating surfactant, and aphrons. The fluids are used in a conventional method of drilling an oil and/or gas well or in conventional methods of servicing or treating such wells, such as in completion, workover, sand control, and frac pack operations, and as spotting fluids to release stuck pipes or tools in a wellbore.

Abstract: Solid, slowly dispersible well treatment composites are provided which have a sufficiently high melting point to prevent melting of the composite in hot weather. The composites have a low solubility and high specific gravity compared to prior art treatment agents; thus the composites readily sink in well fluids and slowly release treatment ingredients over time, depending on the downhole conditions. The composites include a nonylphenol ethoxylate having at least about 50 moles of ethylene oxide per mole of nonylphenol and a fatty acid amide having from 16-20 carbon atoms. Preferably, the composites further include a weighting agent and active ingredients selected from the group consisting of corrosion inhibitors, scale inhibitors, bactericides, scale converters, foaming agents, and mixtures thereof.

Abstract: An improved method of fluid analysis in the borehole of a well. A fluid sampling tool is fitted with a pumpout module that can be used to draw fluids from the formation, circulate them through the instrument, and then expel this fluid to the borehole. It has been determined that certain measurements would be most valuable to implement down hole, such as the formation fluid bubble point and dew point. Accurate bubble point and dew point measurements are made by forming bubbles or a liquid drop in a measured sample, and detecting same.

Abstract: A process for the thermo-hydraulic control of gas hydrates in subsea production and injection wells as well as pipelines which transport liquid or gaseous hydrocarbons is described, the process making use of a Nitrogen Generating System foamed or in solution. The control may signify the prevention of the formation of the gas hydrates or the dissolution of the gas hydrate plug already formed. Under conditions of use designed for the prevention of the formation of gas hydrates the SGN fluid prevents the thermal conditions leading to the gas hydrate plugs. Under conditions of use designed to dissolve the already formed gas hydrate plugs, the SGN fluid alters the thermo-hydraulic conditions which favor the gas hydrate plugs, so that they are dissolved and return to the water+gas phase.

Abstract: The present invention provides improved foamed hardenable epoxy resin sealing compositions and methods which are particularly useful in the construction and repair of wells. The foamed epoxy resin compositions are corrosion resistant and have improved mechanical properties including elasticity and ductility.

Abstract: Methods and compositions for cementing pipe strings in well bores are provided. The compositions are basically comprised of a hydraulic cement, water, an in situ foam generating additive and a water-wetting foam stabilizing surfactant.

Abstract: Cationic polymer-containing gels are stable at elevated temperatures in soft and hard waters.

Abstract: A method of formulating an organo-zirconium compound is accomplished by combining in solution a dialdehyde such as glyoxal with zirconium carbonate. The reacting solution forms an organo-zirconium compound and carbon dioxide which is evolved as a gas from the solution. This eliminates the need to filter or wash the organo-zirconium compound in order to remove undesirable by-products. The organo-zirconium compound can be used as a crosslinking agent for crosslinking aqueous polymer gels used in fracturing fluids for fracturing subterranean formations of oil and gas wells.

Abstract: The disclosed invention provides a method for recovering hydrocarbons from a subterranean formation by injecting an emulsion, comprising oil and water, into the formation. More specifically, the emulsion is stabilized using undissolved solid particles, which are preferably at least partially oleophilic. The solids-stabilized emulsion may be used either as a drive fluid for displacing hydrocarbons from the formation or to produce a barrier for diverting flow of fluids in the formation. Such solid particles may be either formation solid particles (i.e., indigenous to the formation) or nonformation solid particles (i.e., obtained from outside the formation). Nonformation solid particles may either be naturally occurring or synthetic. Some preferred solids include clays, quartz, feldspar, gypsum, coal dust, asphaltenes, and polymers.

Abstract: The present invention relates to improved foamed well cement compositions, additives and methods. The additives, which foam and stabilize a cement slurry containing freshwater or saltwater, are basically comprised of an aqueous solution of an alpha-olefinic sulfonate surfactant and a betaine surfactant.

Abstract: The disclosed invention provides a method for recovering hydrocarbons from a subterranean formation by injecting an emulsion, comprising oil and water, into the formation. More specifically, the emulsion is stabilized using undissolved solid particles, which are preferably at least partially oleophilic. The solids-stabilized emulsion may be used either as a drive fluid for displacing hydrocarbons from the formation or to produce a barrier for diverting flow of fluids in the formation. Such solid particles may be either formation solid particles (i.e., indigenous to the formation) or nonformation solid particles (i.e., obtained from outside the formation). Nonformation solid particles may either be naturally occurring or synthetic. Some preferred solids include clays, quartz, feldspar, gypsum, coal dust, asphaltenes, and polymers. Carbon dioxide or another gas may be added to the emulsion to adjust the emulsion's viscosity to the desired level.

Abstract: A process employing a foamed gel in a subterranean hydrocarbon-bearing formation to reduce the permeability of a treatment region therein or control the mobility of a drive fluid in the formation. The foamed gel is formed from a crosslinkable carboxylate-containing polymer, a crosslinking agent containing a reactive transition metal cation, a polyvinyl alcohol, an aqueous solvent, and an added gas.

Abstract: The present invention is directed to an aqueous foamed Drilling Fluid for drilling well bores into a subterranean formation, comprising water, at least one clay and at least one foaming agent. According to the invention, it further comprises at least one metal hydroxide. The invention further relates to a method for preparing said foamed drilling fluid.

Abstract: Foamed cement slurry compositions and a process or method for cementing well casings or pipes utilizing such compositions are described, the compositions being characterized by critical ratios of particular solid and liquid components. The slurry compositions formed provide unique properties such as rapid set or hydration, and are designed particularly for use with weakly consolidated formations.

Abstract: The present invention provides lightweight, fast setting cement compositions and methods which can be utilized in performing a variety of well cementing operations. The cement compositions are basically comprised of slag cement, water sufficient to form a pumpable slurry, a gas sufficient to foam the slurry and a foaming agent.

Abstract: Polymer enhanced foam fluid is utilized for completion, workover, and kill operations in wells penetrating subterranean formations. The foam is formed by appropriately adding a gas to an aqueous solution of a substantially noncrosslinked water soluble polymer and a surfactant. The solution and the foam are substantially free of crosslinking agents. The foam may be generated at the surface or in a wellbore.

Abstract: A process employing a foamed gel in a wellbore as a completion, workover, or kill fluid. The foamed gel is formed from an aqueous solvent, a water-soluble carboxylate-containing polymer crosslinked by a crosslinking agent containing a reactive transition metal cation, a surfactant, and an added gas. The foamed gel is placed in the wellbore, where it substantially prevents the flow of formation fluid into or out of the wellbore. The completion, workover, or kill operation is then performed. Alternatively, the foamed gel may be combined with another completion, workover, or kill fluid after commencing a wellbore operation.

Abstract: A process for the thermo-chemical dewaxing of hydrocarbon transmission is described, which comprises, after assessment of the conduit internal effective volume, treating the wax-containing conduit with a water-in-oil emulsion, co-currently to the production flow. The emulsion contains inorganic reactants which generate nitrogen and heat, which fluidize the paraffin deposit which is later driven off by cleaning beds. The percentual of removed paraffin is known by assessing the final internal effective volume.

Abstract: The present invention provides lightweight, fast setting cement compositions and methods which can be utilized in performing a variety of well cementing operations. The cement compositions are basically comprised of slag cement, water sufficient to form a pumpable slurry, a gas sufficient to foam the slurry and a foaming agent.

Abstract: An aqueous foamed fracturing fluid composition and method for using the foamed fracturing fluid for fracturing subterranean formations that have been penetrated by a wellbore wherein the foamed fracturing fluid comprises: (a) a viscosifier which is preferably either hydrophobically modified guar or hydrophobically modified hydroxymethylcellulose; (b) a surfactant which is preferably alpha olefin sulfonate; and (c) the gas phase includes either nitrogen or carbon dioxide.

Abstract: The invention is a foam method for improving conformance during a steam flood or carbon dioxide flood in a subterranean, oil-containing formation penetrated by at least one injection well and at least one production well. In a steam flood oil recovery process, sweep efficiency is improved by injecting steam until steam breakthrough occurs at the production well after which a mixture of steam, a noncondensible gas, and an aqueous surfactant-polypeptide solution is injected into the formation. The aqueous surfactant-polypeptide solution forms a stable foam with the formation oil at formation conditions that reduce the permeability of the highly permeable steam swept zones thereby diverting the steam to other portions of the formation containing unswept oil. The polypeptide is used as a partial substitute for the surfactant to improve the cost of the foam-forming mixture without reducing its effectiveness in increasing sweep efficiency.

Abstract: A method of reducing fluid loss into a highly conductive formation interval during drilling and completion of a well through such an interval wherein a foamed cement slurry, including an acid or oil soluble component, is injected into the well and forced into the conductive portions of the formation zone, which may comprise a fractured or rubblized formation portion. The cement is allowed to harden or set at a porosity of at least 15%, followed by resuming drilling and, in completing the well, dissolving the soluble component to increase the permeability of or disintegrate the cement to permit production of formation fluids into the well.

Abstract: A method for acidizing a subterranean formation wherein a specific foam is used to block flow through the higher-permeable zones of the formation while the acid is being injected therein. The foam is generated from a surfactant solution comprised of a blend of surfactants comprised of a nonionic primary surfactant (e.g. ethoxylated alcohol or polyglycosides) a cationic co-surfactant (e.g. fluorinated quaternary ammonium chloride). A polymer (e.g. polysaccharides or partially hydrolyzed polyacrylamide) may be added to the surfactant solution to enhance the foam mobility reduction and a co-solvent (e.g. polyol) may be added if necessary to maintain the surfactant/polymer complex in solution.

Abstract: A well, such as an oil or gas well, may be revived and or increase the flow of hydrocarbons from the well, by inserting a surfactant/chemical solution in solid stick form into the wellbore through the wellhead. The soap stick falls down the production tubing or casing due to gravitational pull and upon contacting the undesired well fluid(s) instantly reacts with the fluids to transform the fluids into foam, thus lightening the hydrostatic pressure being applied to the producing formation and increasing the flow of hydrocarbons. The sticks are manufactured by melting solid surfactants and or foamers to liquid form, then mixing the hydrogen gas producing chemicals and or acid solutions uniformly in the molten surfactants and or roamers, then pouring the molten mixture into various sized containers. When the mixture cools, it returns to solid form ready for use. The surfactant(s) are low moisture content foamers, the chemical(s) are hydrogen gas producing compounds which react violently with the downhole fluids.

Abstract: The invention is a foam method for improving conformance during a steam flood or carbon dioxide flood in a subterranean, oil-containing formation penetrated by at least one injection well and at least one production well. In a steam flood oil recovery process, sweep efficiency is improved by injecting steam until steam breakthrough occurs at the production well after which a mixture of steam, a noncondensible gas, and an aqueous surfactant-polypeptide solution is injected into the formation. The aqueous surfactant-polypeptide solution forms a stable foam with the formation oil at formation conditions that reduce the permeability of the highly permeable steam swept zones thereby diverting the steam to other portions of the formation containing unswept oil. The polypeptide is used as a partial substitute for the surfactant to improve the cost of the foam-forming mixture without reducing its effectiveness in increasing sweep efficiency.

Abstract: A process employing a foamed gel in a wellbore as a drilling fluid, lost circulation fluid, or combined drilling/lost circulation fluid during the wellbore drilling operation. The foamed gel is formed from a crosslinkable carboxylate-containing polymer, a crosslinking agent containing a reactive transition metal cation, a surfactant, an aqueous solvent, and an added gas.

Abstract: A method is presented for cementing conductor pipes in well bores in water depths greater than 1000 feet. The method is accomplished by formulating the cement slurry from Portland cement, a foaming surfactant, a quantity of fine particle size cementitious material and nitrogen or other gas to foam the slurry to yield a density of from about 9.0 to about 14 lbs/gal. The slurry is introduced down the conductor pipe and permitted to return up the annulus of the well bore to the seafloor. The slurry develops a static gel strength in excess of about 500 lbf/100 ft.sup.2 within less than about 30 minutes after placement.

Abstract: An improved method for hydraulically fracturing a formation or reservoir where a thermo-setting gellable mixture is utilized. This thermo-setting mixture is foamed either at the surface or in situ under fracturing pressures and conditions. The mixture and carrier fluid is of a composition such that the foamed mixture has a viscosity of sufficient magnitude to cause a created fracture to grow while the foamed mixture is kept under fracturing pressure and conditions. Once a fracture of a desired size and length has been generated, the resin is ignited and thermally set thus forming a porous hardened solid within the fracture thereby holding the fracture open. Once combustion is finished, no spent fracturing fluids or load fluids remain to be recovered. This porous solid props the fracture open thereby increasing the conductivity of the formation or reservoir and fluid flow therefrom.

Abstract: The present invention is a method to improve permeability of a formation in the vicinity of a production wellbore. An acid treatment composition is placed in the formation after a foaming composition is injected and a foam created from the foaming composition, thus forcing the acid treatment composition into less permeable strata. The foaming composition contains a sulfate surfactant as a foam stabilization agent. The sulfate hydrolyzes after a time period that is long enough to permit placement of the acid treatment composition. After the sulfate hydrolyzes, it becomes ineffective as a surfactant. Fluids produced from the formation after the acid treatment according to the present invention therefore do not contain significant concentrations of active surfactants, and therefore do not create foams or emulsions in surface separation equipment.

Abstract: Methods of remedially treating coal bed methane wells to enhance the production of methane therefrom are provided. The methods basically comprise pumping a clean out fluid into the well and into producing zones communicated with the well by perforations therein. The pumping of the clean out fluid is continued while adding perforation sealers thereto to thereby seal perforations and producing zones which are not plugged and to divert the clean out fluid into perforations and producing zones which are partially plugged. An aqueous acid solution is next pumped into the partially plugged perforations and producing zones whereby acid soluble solid materials in the perforations and producing zones are dissolved. The well is shut in, reverse flowed and then returned to production.