Research and application of ultralow interfacial tension oil displacement agent

摘要

An ultralow interfacial tension (IFT) oil displacement agent, which was a surfactant combinational system (HCS) with good salt and heat resistance, was synthesized using amphoteric betaine (AMS)/anionic sulfonate (AKS)/nonionic alkyl amide (NIS). The interface tensiometer was used to test the IFT. The results showed that the oil-water IFT could be as low as 10 4 mN/m when the salinity is 10,000 similar to 50,000 mg/L, the concentration is 1 similar to 5 g/L, and the temperature is 40 similar to 80 degrees C. The surfactant system has good emulsification stability. The displacement simulation experiments demonstrated that the increment of the recovery ratio can be up to 14.1%. The surfactant system could meet the demands of site operation.