DOI: 10.36347/sjet

Pages: 273-276

Chemical flooding adopts polymer to realize flow control generally. But section inversion is serious in the late injection and polymer is easily to block oil layers, compounding the difficulty of chemical flooding. In-house research of ASP flooding and field text has showed that emulsification has a significant impact on oil recovery in chemical flooding. Based on the geological features and fluid characters of major blocks in Daqing oil fields, betaine emulsion with better emulsification ability were chosen to carry experience. The produced fluid scales of reservoir with different permeability were measured by adopting heterogeneous cores with different permeability variation coefficient. Mechanism of emulsion to improve swept volume was analyzed as well by comparing produced fluid characters of surfactant flooding. The study showed that for three layers heterogeneous cores with even permeability of 400 ×10-3μm2 and permeability variation coefficient of 0.72, oil recovery of emulsion flooding is more than water flooding by 16.98% and fluid production of middle-low permeability layers is increased by 16%. And Emulsion flooding can control mobility, which can avoid channeling phenomenon in surfactant flooding; it can also push and shove to displace residual oil. It can adjust the profile and improve “fingering phenomenon”.