Immiscible CO2 Flooding Efficiency in Low-Permeability Reservoirs: An Experimental Investigation of Residual Oil Distribution

Residual oil distribution plays a critical role in understanding of the CO 2 flooding processes, but its quantitative research for reservoirs with different permeability levels rarely has been comprehensively conducted laboratory. This article presents results an experimental study on immiscible displacement efficiency core samples and various patterns prior to after flooding. Experiments were four extracted from selected field range 0.210–66.077 mD. The show that can mobilize ultralow-permeability environment achieve reasonable (40.98%). contribution varies permeabilities. With increase permeability, cluster intergranular pore increases. However, corner film tends lower permeability. Therefore, is recommended case, especially larger amount patterns. calculated by experiment agrees reasonably well frozen slices observation. this have practical significance refers effective development low-permeability reservoirs.