Abstract: The present invention relates to a process for the enhanced recovery of oil in a deposit owing to the introduction, into the deposit, of an alkaline aqueous solution of a water-soluble polymer containing a surfactant, characterized in that the aqueous solution of water-soluble polymer introduced is prepared with an aqueous solution initially containing Ca2+ and Mg2+ ions treated with an alkaline agent and a dispersant, so as, prior to the introduction of the polymer and of the surfactant into the aqueous solution, to precipitate, under the action of the alkaline agent and of the CO2 optionally dissolved in the aqueous solution, the Ca2+ and Mg2+ ions, especially in the form of precipitates of calcium carbonate and of magnesium hydroxide, and to disperse said precipitates owing to the dispersant, chosen in order to limit the size of the calcium carbonate and magnesium hydroxide precipitates formed.

Abstract: Installation for flocculation of water or sludge loaded with suspended matter comprising in succession: a polymer storage hopper, a polymer grinding device, and a line, pipe or other conveyor for transferring the polymer solution to the water or the sludge to be treated. The grinder device includes a wetting cone in which the polymer is poured, and at the bottom end of the cone: a chamber for grinding and removing the dispersed polymer comprising: a rotor, a stator, and a ring fed by a secondary water circuit. A method implementing the installation is also provided.

Abstract: A method for enhanced oil recovery in an oil-bearing formation having high permeability zones constituting preferential passages for the injected liquid includes the steps of: a) treating the preferential passages by injection into the formation of an aqueous solution based on watersoluble polymers at a concentration such that the viscosity of the aqueous solution is higher than that of the oil, and b) once step a) is completed, an aqueous solution is injected having an identical composition to that used in step a at a lower polymer concentration.

Abstract: Enhanced oil recovery method consisting in continuously dissolving, in the injection water, a stable invert emulsion of acrylamide (co)polymer containing at least one inverting agent, and a water soluble polymer, whereby: in a first step, the emulsion is prediluted in a first static mixer to a (co)polymer concentration of at least 5 g/l, the difference of pressure between the mixer outlet and inlet being at least 2 bar, in a second step, the suspension from the first mixer is diluted in a second static mixer to a concentration corresponding to the injection concentration of the water in the well of between 500 and 3000 ppm, the difference of pressure between the mixer outlet and inlet being at least 1 bar.

Abstract: Installation for enhanced oil recovery comprising in succession: a polymer storage hopper, a grinding device and a pressurized injection pump. The grinding device has a chamber for grinding and draining the dispersed polymer comprising a rotor and a stator, and on all or part of the periphery of the chamber, a ring fed by a secondary water circuit. The ring communicates with the chamber for spraying of pressurised water on the blades of the stator. A method implementing the installation is also provided.

Abstract: Installation for enhanced oil recovery comprising in succession: a polymer storage hopper, a grinding device, a dissolution/maturation tank for the dispersed polymer, and a pump for transferring pressurized polymer solution in the pipeline conveying the injection water for introducing the mixture of polymer and injection water into a well. The grinding device has a chamber for grinding and draining the dispersed polymer comprising a rotor and a stator, and on all or part of the periphery of the chamber, a ring fed by a secondary water circuit. The ring communicates with the chamber for spraying of pressurized water on the blades of the stator. A method implementing the installation is also provided.

Abstract: Installation for flocculation of water or sludge loaded with suspended matter comprising in succession: a polymer storage hopper, a polymer grinding device, and a line, pipe or other conveyor for transferring the polymer solution to the water or the sludge to be treated. The grinder device includes a wetting cone in which the polymer is poured, and at the bottom end of the cone: a chamber for grinding and removing the dispersed polymer comprising: a rotor, a stator, and a ring fed by a secondary water circuit. A method implementing the installation is also provided.

Abstract: Installation for enhanced oil recovery comprising in succession: a polymer storage hopper, a grinding device, a dissolution/maturation tank for the dispersed polymer, and a pump for transferring pressurized polymer solution in the pipeline conveying the injection water for introducing the mixture of polymer and injection water into a well. The grinding device has a chamber for grinding and draining the dispersed polymer comprising a rotor and a stator, and on all or part of the periphery of the chamber, a ring fed by a secondary water circuit. The ring communicates with the chamber for spraying of pressurised water on the blades of the stator. A method implementing the installation is also provided.

Abstract: Device for dispersing a water-soluble polymer comprising: a chamber for grinding and draining of the dispersed polymer comprising a rotor and a stator, and on all or part of the periphery of the chamber, a ring fed by a secondary water circuit. The ring communicates with the chamber for spraying of pressurised water on the blades of the stator. A method implementing the device is also provided.

Abstract: Installation for enhanced oil recovery comprising in succession: a polymer storage hopper, a grinding device and a pressurized injection pump. The grinding device has a chamber for grinding and draining the dispersed polymer comprising a rotor and a stator, and on all or part of the periphery of the chamber, a ring fed by a secondary water circuit. The ring communicates with the chamber for spraying of pressurised water on the blades of the stator. A method implementing the installation is also provided.

Abstract: Improved process for fluidifying flocculated aqueous suspensions of red muds in the production of alumina from bauxite by the Bayer process, which consists:in dissolving bauxite using sodium hydroxide;then, in decanting and in washing the red muds formed in order to separate them from the alumina in successive vats, while recycling the washing waters upstream;and finally, in eliminating the red muds thus treated;and in which a flocculant (F) consisting of a polyacrylamide of molecular weight greater than ten million is introduced into the suspension of one of the successive vats;wherein a dispersing agent (D) formed by an anionic acrylic acid polymer of molecular weight lower than fifty thousand is added simultaneously with said flocculant (F) to the suspension in the same vat.