Laboratory Investigation Of Polymer-Surfactant System

With the progress of exploration, Daqing oil field has turned into high-water period. ASP flooding is another important EOR technology after polymer flooding. Field application indicates that ASP flooding can enhance oil recovery over 20%, but many problems follows. Among of them, the most severe effect on formation is that alkaline can lower formation permeability because it can disperse formation clay and make them move and swell. Alkali scale forms after it reacts with formation fluid and rock, which does harm to formation. At the same time, alkali scale forms in the oil well to reduce the production, shortens period of checking pump etc. Alkali makes it difficult to demulsify for production fluid and can lower largely viscoelasticity of polymer. Future researches focus on surfactant-polymer flooding technology.In this paper, interfacial tension, viscosity, emulsification performance of polymer-surfactant system that mixes RMA-1 surfactant with polymer are evaluated. Chromatographic separation effect and compatibility of the system is studied. Static and dynamic adsorption capacities of polymer-surfactant system are measured. Displacement effectiveness of binary system is systematically studied by physical simulation experiments. Experiment results indicate that interfacial tension of the polymer-surfactant system and crude oil from different factories is lower than 10-3 mN/m among wide range of surfactant concentration and this polymer-surfactant system is composed of RMA-1 surfactant and ultra high molecular weight (UHMW) polymer. The stability of viscosity and interfacial tension is better. The crude emulsion is stable and it has good emulsification effect. Physical simulation experiment results show that the polymer-surfactant system can enhance oil recovery over 20%.