Abordagem experimental da recuperação de óleo por injeção de soluções poliméricas

Abstract

Polymer flooding is one of the most applied chemical methods for enhanced oil recovery. The technique allows to increase the oil recovery factor in mature fields, so to produce more oil from the explored reservoirs. Therefore, considering the variety of polymers available and the different reservoir conditions, it is necessary to study how these factors impact oil production. Thus, the present work aimed to evaluate the impact of the polymer flooding on the oil recovery factor in porous media under high pressure confinement. For it, polymeric solutions were prepared using partially hydrolyzed polyacrylamides (HPAM) with different molecular weights. Solutions were rheologically characterized, showing a pseudoplastic behavior and a viscosity increase with the polymer molecular weight increasing. Were performed four flooding experiments with high-permeability synthetic sandstone cores. The displaced fluid was the synthetic oil Petronas Selenia 5W30 API SN, with 126 cP viscosity. The results showed that the water flooding results in an average recovery factor of 40,25%. When the polymer flooding is performed, after the water flooding, the average recovery factor is 70,33%. The experiments also show that porous media higher permeability combined with polymer solutions higher viscosity favors the oil recovery.