Experimental investigation of the influence of pore geometry on laboratory water-oil relative permeability and oil recovery

Abstract

Pore geometry dictates the preferential pathways of fluids in the porous medium, impacting water-oil relative permeability and oil recov ery efficiency. This work investigates the influence of pore geometry on laboratory-measured porosity, relative permeability and oil recovery on both three varied size homogeneous and heterogeneous samples based on sand and sand with 20% of clay, then a new PVC-designed mesofluidic system to visualize fluid- fluid displacement, to determine oil recovery and set up a preliminary investigation of thermal Enhanced Oil Recovery (TEOR). All the experiments were conducted under laboratory conditions. The results showed variations in oil relative permeability which increases as grain size increasing (0.643D for 500 μm, 0.535D for 250 μm, 0.503D for 125 μm and 0.654D for the polymodal sample). Also due to the presence of clay the polymodal sample revealed a decrease of oil relative permeabilityfrom 0.654D to 0.510D. The incremental oil recovered for the polymodal sample was 13 ml. For the PVC-designed mesofluidic system several fluid pathways were observed with 17.084 ml of oil recovery, where the steam was injected under 130 ºC to extract an amount of 6% from 55.22% of the trapped oil.