Abstract: In order to transport hydrates in suspension in a fluid comprising water, gas and a liquid hydrocarbon, at least one non-polluting composition consisting essentially of a mixture comprising at least one ester associated with a non-ionic co-surfactant of the polymerized (dimer and/or trimer) carboxylic acid type is incorporated into said fluid. The composition is generally introduced in a concentration of 0.1% to 5% by weight with respect to the liquid hydrocarbon.

Abstract: A well drilling method comprises removing the drilling cuttings using an aqueous drilling fluid such as a foam including a foaming agent which includes at least one mono-(aliphatic hydrocarbyl) phosphate ester. More specifically, the drilling fluid takes the form of a potassium and/or alkanolamine and/or alkylalkanolamine salt, the foam also comprising a foam stabiliser.

Abstract: The invention relates to a well drilling method consisting in removing the drilling cuttings using an aqueous drilling fluid such as a foam including a foaming agent which is, or includes, at least one mono-(aliphatic hydrocarbyl) phosphate ester. More specifically, the drilling fluid takes the form of a potassium and/or alkanolamine and/or alkylalkanolamine salt, said foam also comprising a foam stabiliser.

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 present invention relates to a cement slurry set in a wellbore. The slurry comprises cement, at least one mineral filler, water and a determined amount of at least one hydrophobically modified acrylamide or acrylate derivative. The present invention also relates to an additive specific to a cement slurry and acting as a filtrate reducer and as a rheological control agent, the additive comprising mainly a hydrophobically modified acrylamide or acrylate derivative.

Abstract: The present invention relates to a method intended for analysis and measurement on constituents carried by a well fluid during drilling operations, wherein the following stages are carried out:

Abstract: A temperature-stable, non eco-toxic oil-base well fluid that is particularly suitable for high pressure/high temperature drilling comprises an emulsification system comprising at least one superamide that may or may not be polyalkoxylated, optionally associated with a non-ionic co-surfactant. The oil-base well fluid comprising such a system can be used at temperatures of up to about 200° C. due to the production of highly temperature-stable reverse emulsions.

Abstract: A lightened cement slurry for cementation of a well includes cement, at least one mineral filler, water, and resin particles obtained by polymerization from vinyl aromatic, alkyl acrylate or acrylic monomers, wherein the polymerization includes crosslinking.

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: Method of determining the gas hydrate formation conditions in a well fluid, comprising the following stages: taking a fluid sample, placing this sample in a calorimetry cell, performing on this sample a reference thermogram in a temperature range between T1 and T2, performing on the same sample a second thermogram in the same range and under a pressure Ph of a hydrocarbon gas, T1 being a temperature low enough to obtain the formation of hydrates in the sample at a gas pressure Ph, T2 being high enough to obtain hydrate dissociation, identifying a peak in the second thermogram corresponding to the hydrates dissociation zone and deducting therefrom a hydrates dissociation temperature.

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: Method of determining by numerical simulation the optimum conditions to be applied in a horizontal (or complex) well drilled through an underground reservoir so as to progressively eliminate (restore), by the fluids from the reservoir, deposits or cakes formed in at least a peripheral zone of the well as a result of drilling and completion operations.

Abstract: Method of determining the gas hydrate formation conditions in a well fluid, comprising the following stages:

Abstract: An organic based emulsion-breaking formulation for use in treating well bores drilled in oil-bearing mud that is not eco-toxic and is optimally compatible with formation fluids comprises:

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

Abstract: The present invention relates to the cementation of a well, notably an oil well, by means of a low-density grout.

Abstract: An oil-based demulsifying formulation which can be used in the treatment of drains bored in oil-based mud, non ecotoxic and optimally compatible with formation fluids, comprises at least one wetting agent selected from the group consisting of anionic surfactants and at least one demulsifier (or “emulsion breaker”) selected from the group consisting of copolymers of ethylene oxide and propylene oxide, alcohol or phenol derivatives with alkoxylated or polyalkoxylated chain formations, polyalkyleneglycols, polyamines, alkoxylated or polyalkoxylated derivatives of amines, quaternary ammonium salts, quaternized alkanolamine esters, alkyl esters of fatty acids or natural oils, possibly alkoxylated or polyalkoxylated, and silicated derivatives such as polysiloxanes.

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: The present invention relates to a cement slurry set in a wellbore. The slurry comprises cement, at least one mineral filler, water and a determined amount of at least one hydrophobically modified acrylamide or acrylate derivative.