Evaluation On Performance Of SP System In Daqing Oilfield

Different aspects of characters of polymer-surfactant composite solutions were selected analyzed and evaluated in this paper(mainly including polymer-surfactant system microcosmic flooding principle, polymer-surfactant system rheology retention and adsorption and flooding effect evaluation, etc.). The influence of mass concentration and molecular weight on the viscosity of polymer solution was studied, as well as the influence of mass concentration and surfactant on the interfacial tension of the solutions. Depending on the viscosity and interfacial tension to calculate the capillary number of different solutions. From the perspective of the capillary number to study the mobility of polymer-surfactant solutions. Increasing the concentration of polymer or surfactant can magnify capillary number. Through core seepage experiment, the retention and adsorption effect of polymer-surfactant system were studied as well.Multiple aspects of experiments were carried out in the lab. Results showed that the larger polymer molecular and its concentration was the greater viscosity of polymer-surfactant system would be. Increasing of surfactant concentration would not lead to the change of viscosity. The largest N1 appeared when polymer concentration reached 2000mg/L and concentration from 500mg/L to 1500mg/L was successively reduced. Larger surfactant concentration(mass concentration was greater than 0.2%) would achieve ultra low interfacial tension(reached 10-3mN/m magnitude). Improving polymer concentration would indeed increase its viscosity as well. Through injecting 20 PV of polymer-surfactant composite solutions(injection quantity is large enough). Its output belonged to stable interfacial tension which proved that its adsorption had reached equilibrium. Through flooding experiments, the capillary number and recovery possessed the same transformation law. The greater the capillary number system(within certain limits) was, the greater corresponding chemical flooding would be and the lower the residual oil saturation would become.