The extraction effect of CO2 injection on the flow properties of crude oil

During CO2 flooding, extraction of lighter hydrocarbons from crude oil makes the remaining oil hard to be recovered. In this work, we design a new experimental method to characterize the effect of CO2 extraction on crude oil. The experimental results show that, the volume of extracted hydrocarbons increases as system pressure increases. The hydrocarbons with wider carbon number can be extracted from crude oil at high pressures. Moreover, the wax precipitation and viscosity of the remaining oil increase with increasing pressure. This study is expected to provide the basic understanding of the mechanisms of CO2 flooding for enhanced oil recovery.