Abstract: To address the problems of poor physical properties, high heterogeneity and high salinity of the target reservoir in M Oilfield, the temperature and salt resistance of a new dialkyl glycerol ether-derived surfactant (diGE-EO) was studied in this paper, the injection performance was compared with Hall curve between the polymer and the polymer-surfactant binary salt resistance system, and the feasibility of polymer-surfactant binary displacement system to enhance oil recovery in the target reservoir of Minsk Oilfield was analyzed. The study results show that The diGE-EO can maintain high salt resistance at concentrations higher than 3 500 mg/L, and can reduce the oil-water interfacial tension to 5.73×10^-3 mN/m after being placed at 85 ℃ for more than 45 days, which is in the ultra-low interfacial tension range, meeting the requirements for the development of highly mineralized reservoirs. The injection performance of polymer-surfactant binary anti-salt system is also analyzed. The results show that when the mass concentration of polymer solution is up to 1 500 mg/L and the core permeability is lower than 200 mD, and it becomes more difficult to inject polymer alone; in the presence of surfactant, the injection performance is significantly improved. The test results provide a laboratory test basis for the scheme design and field implementation of binary composite flooding project in M oilfield.

Key words: polymer-surfactant binary combination flooding, injection performance, surfactant, salt-resistant system, recovery