Polyacrylamide (PAA) is one of the most widely used polymers in the oil industry. Field experience shows a difficulty in preparing high-quality aqueous solutions of PAA when used directly in field conditions. The dissolution of PAA in water is greatly hindered by its tendency to form lumps after contact with water. It is noted that such lumps do not dissolve even after many hours of mixing. In production conditions, the process is complicated by low temperatures, the use of non-specialized equipment, usually low-capacity stirrers, and the influence of erroneous personnel actions. The authors have developed a new original method for kneading aqueous solutions of PAA supplied in solid powder form. The method involves preliminary impregnation of PAA powder in a hydrophobic hydrocarbon liquid. Impregnation eliminates the problem of the formation of lumps, while the speed and volume of introduction of the powdered form of PAA into water becomes not critical. Laboratory studies carried out during the work showed that mixing aqueous solutions of PAA using the new technology does not worsen their rheological parameters compared to solutions qualitatively prepared by a standard method. Field tests at the oil fields of the Udmurt Republic confirmed the effectiveness of the proposed technology. Tests were performed during repair and isolation work at production wells to isolate depleted and watered intervals of the formation in order to increase the efficiency of the cement mortar used. This repair and insulation work involves preliminary injection of a polymer composition based on PAA to create a gel screen before pumping cement slurry. The developed technology guarantees the quality and simplicity of preparation of PAA aqueous solutions, significantly reduces the level of risks associated with the qualifications of personnel, the equipment used, and the impact of climatic conditions.
References
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4. Certificate of
