Experimental study on EOR potential of in-situ water in oil emulsion in the low-temperature conglomerate reservoirs

Oil in water (O/W) emulsion flooding is a successful enhanced oil recovery (EOR) approach for sandstone reservoirs, while few studies have been conducted to examine the EOR potential of water in oil (W/O) emulsion in conglomerate reservoirs. In the current work, the interactions between in situ emulsification system (ISE) and crude oil were investigated at first. Displacement tests were then carried out to examine the formation of W/O emulsion in porous media and highlight its EOR potential. According to experimental findings, ISE could create a W/O emulsion with formation water, demonstrating an effective capacity to control mobility. The interface was given benign viscoelasticity by ISE. Oil recovery of 18.6 %-28.3 % could be significantly increased by 0.6 pore volume ISE flooding and subsequent water flooding, which was mostly attributed to the improvement of mobility control ability, the Jamin effect of water droplets and displacement efficiency of ISE.