A New Arena in Assessing Chemistries Used in Improving Oil Recovery From Shale Reservoirs: A Nano-Fluidic Systematic Study

Abstract This study introduces an innovative experimental approach to enhance oil recovery from liquid-rich shale reservoirs using nanofluidic devices that simulate the nano-scale pore structures of unconventional reservoirs. Shale formations present unique challenges for oil recovery due to their ultra-tight nature, nano-sized pores, and pronounced surface-fluid interactions. Traditional enhanced oil recovery (EOR) methods struggle to overcome the high capillary pressures and confinement effects prevalent at this scale. Therefore, novel methods are essential for studying oil recovery from shale reservoirs. Nanofluidic platforms were employed to replicate reservoir-relevant conditions and investigate fluid displacement dynamics at the nanoscale. For this study, nanofluidic chips were fabricated using reactive ion etching (RIE) on silicon substrates to create 10 nm and 100 nm channels, simulating shale reservoir pores. Through real-time imaging and systematic analyses of interfacial tension (IFT) and wettability, the study provides new insights into the fundamental mechanisms that govern fluid behavior in confined environments. The results highlight the significant impact of pore size on recovery efficiency and underscore the importance of tailoring chemical EOR strategies to nano-scale confinement conditions. This work bridges the gap between theoretical modeling and practical applications, offering a scalable experimental framework for optimizing EOR performance in unconventional reservoirs. The findings have broad implications for improving recovery strategies and advancing sustainable hydrocarbon production from ultra-tight formations.