Flooding Efficiency of Flooding Systems and Wettability Study on the Simulant Rock Surface

In order to research the flooding efficiency of flooding systems and wettability on the simulant rock surface，the orthogonal-test-design method was used to determine the optimal formula for the crude oil from the Chunliang zone of Shengli oil field by transient interfacial tension（IFT）. The results indicate that two optimal formulas are naturally mixed carboxylate SDC-V（0.35%，0.36%），nonionic surfactant FBB（0.06%，0.07%），Alkaline NaHCO3 / Na2CO3 weight ratio of（0.8%，1.2%）and HPAM（0.05%，0.15%），and in the coreflood experiment，their oil recovery are（14.6%，16.7%）OOIP respectively. The contact angles have been determined for the two optimal formula systems and their components on the simulant rock surface，which points out the relationship between the flooding efficiency and contact angle is showed identification，that is，the more oil recovery the less contact angle. It will be useful to the application research of microgravity.