摘要:
A method of reducing the permeability of a subterranean formation comprising contacting the formation with an aqueous polymerizable composition comprising a polymerization monomer, a polymerization catalyst having a latent period, and an alcoholic compound selected from the group consisting of a cyclic ether containing a hydroxymethylene substituent on a carbon atom bonded to the ether oxygen, an aliphatic alcohol having a carbon-to-carbon double bond or a carbon-to-carbon triple bond, and mixtures thereof.
摘要:
High density well drilling, completion and workover brines having low fluid loss to subterranean formations when in contact therewith are provided comprised of water, one or more inorganic salts, and an additive for reducing fluid loss. The additive is comprised of water soluble binary or ternary copolymers formed from vinyl monomers. Methods of use are also provided.
摘要:
A method of treating a permeable structure for the purpose of stabilizing fines in the structure using organic copolymers containing N-vinylpyrrolidone in the copolymer repeat unit.
摘要:
A process for treating a subterranean formation with an aqueous cement composition and minimizing damage to formation permeability by said composition filtrate comprising mixing with said composition at least one polycationic polymer having a molecular weight of about 400 to 6,000,000 prior to treating said formation.
摘要:
This invention provides a process for the hydraulic fracturing of a subterranean formation, which comprises introducing into the formation under fracturing pressure a fracturing fluid comprising solid particulate suspended in a fluid dispersion comprising water, a specified gaseous or supercritical component, and a surfactant component selected from a certain class of polysaccharide compounds. For purposes of this invention, the gaseous or supercritical carbon dioxide and gaseous nitrogen, carbon dioxide and C.sub.1 to C.sub.3 hydrocarbons, and mixtures thereof. The polysaccharide component comprises one or more surfactants of the formula RO(R.sup.1 O).sub.x Sacc.sub.z, wherein R is a monovalent organic radical having a carbon number in the range from about 7 to 24, R.sup.1 represents a divalent hydrocarbon radical containing from about 2 to about 4 carbon atoms, x is a number having an average value in the range from 0 to about 12.0, and Sacc.sub.z represents an average number z between about 0.7 and 10.0 of moieties derived from reducing saccharides containing 5 or 6 carbon atoms. R preferably represents an alkyl, alkylphenyl, hydroxyalkyl phenyl, or hydroxyalkyl moiety having a carbon number in the range from about 8 to about 20; the optional (R.sup.1 O) group is (when present) preferably an oxyethylene group; x is preferably between about 0 and 8.0, and is most preferably 0; Sacc preferably represents a glucose, galactose, glucosyl or galactosyl residue, and most preferably represents a glucose residue; and z is suitably between about 0.7 and 10.0, and is most preferably between about 1.3 and 4.0. Seawater and brines suitably serve as the source of the water. Dispersions formed from these three components are viscous foams which are highly stable under the conditions typically encountered in applications of hydraulic fracturing processes.
摘要:
An improved process for recovering oil by injecting a mixture of noncondensible gas and gas foam surfactant into an oil-containing subterranean reservoir, the improvement provided by using a surfactant enriched in olefin disulfonate. The sulfactant may be used in either a gas drive or a gas soak process. Disulfonate-enriched gas foam surfactants and mixtures are also described.
摘要:
The mobility of fluids in substantially oil-free zones of subterranean formations is controlled by introducing a composition comprising (a) water, (b) a fluid component selected from the group consisting of carbon dioxide, nitrogen, C.sub.1 to C.sub.3 hydrocarbons, and mixtures thereof, and (c) one or more polysaccharide surfactants of the formula RO(R.sup.1 O).sub.x Sacc.sub.z, wherein R is a monovalent organic radical having a carbon number in the range from about 7 to 24; R.sup.1 represents a divalent hydrocarbon radical containing from about 2 to 4 carbon atoms; x is a number having an average value in the range from 0 to about 12; and Sacc.sub.z represents an average number z between about 0.7 and 10 of moieties derived from reducing saccharides containing 5 or 6 carbon atoms. The resulting mixture of components (a), (b), and (c) forms a dispersion, or a "foam" as that term is commonly used in the art, which is resistant to fluid flow.In certain preferred embodiments, the invention is applied to a formation having both one or more zones of high oil saturation and one or more zones which are substantially free of oil. In such embodiments, the process accomplishes a selective reduction of the permeability of a subsequently injected oil displacement or drive fluid into and through the substantially oil-free zones, without significantly reducing mobility of the drive fluid flow into and through the zones having meaningfully high oil saturation.
摘要:
A method of preventing or reducing the migration of fines in a permeable structure comprising contacting the fines with organic copolymers which can be either nonionic in a neutral media or can contain up to 95% by weight of a quaternary ammonium salt monomer.
摘要:
The present invention relates to a method of viscosifying aqueous fluids and a viscosifying composition which when admixed with an aqueous fluid produces a viscosity increase in the fluid in excess of the additive viscosity of the individual composition components. The viscosifying composition comprises at least one member selected from the group consisting of (i) sulfonated guar and a compound comprising at least one member selected from the group consisting of xanthan gum, guar, hydroxypropyl guar, hydroxypropyl guar derivatives, hydroxyethyl cellulose and hydroxyethyl cellulose derivatives and (ii) cationic guar and a compound comprising at least one member selected from the group consisting of hydroxypropyl guar, hydroxypropyl guar derivatives, hydroxyethyl cellulose and hydroxyethyl cellulose derivatives.
摘要:
This invention provides novel aqueous fluid compositions which comprise a synergistic mixture of two classes of water dispersible or soluble polymers, i.e. (1) synthetic polymeric viscosifier and (2) polycationic organic polymer. These compositions are uniquely adapted for use in enhanced oil recovery. Addition of the polycationic organic polymer reduces the solution viscosity, increases the injectivity of the aqueous solution into low permeability formations. This reaction also reduces the shear degradation of the polymers during pumping, injection through the perforations, and during the period of relatively rapid fluid movement as the solution moves through an earthen or subterranean formation in the important zone within about a ten foot radius around the well bore. Once in an earthen formation, the polycationic organic polymer is rapidly adsorbed from the solution resulting in an increase in solution viscosity and improving the mobility ratio and also resulting in enhanced and/or increased oil recovery.