Governing mechanism of nanofluids for CO₂ EOR

Carbon dioxide (CO2) flooding is one the most widely applied enhanced oil recovery (EOR) method. Even though the method possesses the advantage of having excellent recovery mechanism such as zero capillarity, miscibility at favorable conditions, etc., they are prone to several limitations such as high mobility, poor sweep, etc. In recent times, CO2 sequestration is becoming an integral part of an EOR project so that CO2 emission to atmosphere can be minimized. For sequestrating CO2 within the porous media, wettability of rock surface is important. In this chapter, we shall discuss the basic EOR concepts, the limitations faced by CO2 during EOR and the associated reasons, the improvements made to address the limitations and their shortcomings. Then we provide a discussion about the nanoparticle (NP), its special feature, how and why it provides advantage to CO2-EOR and sequestration by summarizing from the key literature.