Abstract: Heavy crude transportation optimization method wherein at least one solvent consisting of a petroleum cut is added to said crude. According to the method, the polar component ?p of the Hildebrand parameter of the solvent is increased, and the contribution of hydrogen bond ?h of the Hildebrand parameter of the solvent is controlled, by adding a predetermined amount of at least one specific additive.

Abstract: The present invention relates to a method and to a fluid for drilling or workover in a well running through a porous permeable formation, wherein a water-based well fluid circulates in said well. In the method, at most 3% by weight of a composition obtained from fat, or an oil, and an alcohol, is added to the fluid in addition to the conventional constituents for such a fluid, the chain lengths of the acid and alcohol parts being chosen such that the ester thus obtained has sufficient dispersion in water, compatibility with said constituents, does not form an emulsion with the reservoir oil and adsorbs sufficiently on the porous formation.

Abstract: The invention relates to a method of transporting a viscous petroleum effluent in pipes, wherein the following stages are carried out: separating the effluent into at least a solid phase consisting of particles coming from the colloidal elements acting on the viscosity of said effluent and into a fluidized liquid phase, keeping an amount of particles dispersed in said fluidized liquid phase so as to obtain a suspension (2), and circulating the suspension in the pipe.

Abstract: The present invention relates to a stable emulsion of an immiscible fluid and of an aqueous phase having a determined pH value. The emulsion is optimized in that it comprises an ionic surfactant and a polyampholytic polymer whose charge depends on the pH value. The respective amounts of surfactant and of polymers are determined according to the charges. Stabilization or destabilization of the emulsion is adjusted by controlling the pH value. The invention also relates to a method of stabilizing and destabilizing an emulsion comprising a surfactant combined with an ampholytic polymer.

Abstract: The present invention relates to an emulsion and to its manufacturing method. The emulsion is optimized in that it is stabilized by the presence of a surfactant specifically selected according to the type of a polymer, or copolymer, also present in the emulsion. The surfactant and the polymer are selected oppositely charged.

Abstract: The present invention relates to a borehole fluid comprising a lubricating compound containing at least one amphiphilic non-ionic compound obtained by reacting at least one vegetable oil or fatty acid as such or in a polymerized state on at least one amino alcohol. In one variant, the compound can be mixed with a solvent. The invention also relates to a method for verifying the lubrication power of a water-based fluid. The invention further relates to the application of said method to borehole fluids with a high pH.

Abstract: The present invention relates to a method and a fluid for drilling or intervening in a well passing through a porous, permeable formation, wherein a water-based well fluid is circulating in said well. In this method, there is added to the fluid not only the conventional ingredients for such a fluid but also a maximum of 10 wt. % of a composition obtained from a grease or oil and an alcohol, with the chain lengths of the acid and alcohol parts being chosen such that the ester thus obtained has sufficient dispersion in water, compatibility with said ingredients, does not form an emulsion with the reservoir oil, and adsorbs sufficiently on the porous formation.

Abstract: The process according to the invention includes the combination, with a liquid phase change material (PCM), of a texturing agent chosen so as to greatly reduce the thermal convection and whose viscosity is decreased reversibly under shearing. The material formed has a gelled consistency when at rest, and fluidized under shearing. The PCM comprises a mixture of chemical compounds from the alkane family: paraffins, waxes, fatty alcohols, fatty acids etc., and the texturing agent is a high mass polymer (hydrocarbonate polymers, ester or ether polymers, mixed ester-hydrocarbon polymers), an ionomer polymer or a di, tri or multi-block styrene copolymer (SBS: styrene-butadiene-styrene, SEBS: styrene-ethylene-butadiene-styrene).

Abstract: The present invention relates to a process of obtaining microcapsules, comprising mainly the following stages: preparing a scarcely water-soluble organic phase containing a determined amount of acid chlorides, forming an emulsion of said organic phase in an aqueous phase, adding to the aqueous emulsion an amount of at least one polyoxyalkylene polyamine, reacting the monomers containing the amine and acid chloride functions so as to form a polyamide membrane around the emulsified organic phase, recovering the microcapsules obtained. The present invention also relates to a microcapsule.

Abstract: The present invention relates to a method and to a fluid for drilling or workover in a well running through a porous permeable formation, wherein a water-based well fluid circulates in said well. In the method, at most 3% by weight of a composition obtained from fat, or an oil, and an alcohol, is added to the fluid in addition to the conventional constituents for such a fluid, the chain lengths of the acid and alcohol parts being chosen such that the ester thus obtained has sufficient dispersion in water, compatibility with said constituents, does not form an emulsion with the reservoir oil and adsorbs sufficiently on the porous formation.

Abstract: The present invention relates to a well fluid for releasing tubular elements stuck in the well. The fluid comprises a part A consisting of one or more esters obtained by reaction of a linear or branched monocarboxylic acid (A.1) having between 8 and 24 carbon atoms and a linear or branched polyol (A.2) having between 2 and 20 carbon atoms, a part B consisting of one or more linear or branched monocarboxylic acids having between 8 and 24 carbon atoms, where the carboxylic acid (A.1 and part B) is a mixture of at least 80% carboxylic acids having between 1 and 3 insaturations, and a part C consisting of a different ester or olefins, the quantity of part C is determined in relation to the other components in such a way that the viscosity of the fluid is lower than 40 mPa·s at 40° C. The invention also relates to a method for releasing drillpipes stuck in a well.

Abstract: The present invention relates to a process of obtaining microcapsules, comprising mainly the following stages:

Abstract: The present invention relates to more or less substituted acrylamide or acrylate and zwitterion monomer hydrosoluble copolymers.

Abstract: This invention concerns a process for controlling filtration loss during the installation of slag cement in a well. The procedure entails the addition of a specific quantity of at least a derivative of galactomannan, hydrophilically and hydrophobically modified. In one version, the derivative is hydrophobically modified hydroxy propyl guar (HMHPG). This invention concerns slag cement and a filtrate reductant additive containing a specific quantity of at least a derivative of galactomannan, hydrophilically and hydrophobically modified.

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 invention concerns a water-based additive for well fluid, comprising an acrylamide and branched styrene sulphonate copolymer. It also concerns a water-based fluid comprising an acrylamide and branched styrene sulphonate copolymer. The additive is useful for controlling the filtering of a well fluid through the wall. The invention is advantageously applicable to drilling and/or completion of oil wells having a temperature higher than 120° C.

Abstract: For controlling filtration loss during the installation of climber cement in a well, the procedure entails the addition of a specific quantity of at least one derivative of galactomannan, hydrophilically and hydrophobically modified, a hydrophobically modified hydroxy propyl guar (HMHPG).

Abstract: Hydrosoluble copolymers made of hydrophilic monomers, e.g., acrylamide, and of silane or siloxane derivative-based hydrophobic monomers, e.g., a silane or or siloxane acrylate, is obtained by micellar or heterogeneous radical copolymerization, and such copolymers can be used as rheology control agents in, e.g., a well bore.

Abstract: The invention concerns a water based foaming composition and the method of making it. The composition is optimized in that it contains a surfactant specifically selected according to the polymer also present in the composition. The surfactant and the polymer are selected so that they are oppositely charged. The invention is very useful in drilling or treating wells.