Experimental and numerucal study of ZnO and AL2O3 nanoparticles effect on wettability alteration in heavy oil reservoir

Reversing rock wettability to more water-wet state can give significantly improved oil recovery. This study provides new insights into ZnO and Al₂O₃ nanoparticles effects on wettability alteration. The main objectives were to determine the potential of both nanoparticles to alter wettability experimentally and numerically. Laboratory tests were conducted in three experiments on four cylindrical core samples (three sandstones and one carbonate) taken from Iranian heavy oil reservoir. In the first experiment, core samples saturated with crude oil and in the second and third ones, nanoparticles flooded into core samples and then saturated with crude oil for about two weeks and after that they immersed in distilled water and the amount of recovery was monitored during 30 days for all tests. Experimental results showed oil recoveries for sandstone cores changed from 20.74, 4.3 and 3.5 % of OOIP without nanoparticles to 36.2, 17.57 and 20.68% of OOIP with ZnO and 25.4, 9.12 and 6.35% of OOIP with Al2O3 respectively. The oil recoveries for carbonate core varied from zero without nanoparticles to 8.89% and 4.2% of OOIP with ZnO and Al2O3 respectively. Modelling of relative permeability curves showed the crossover-point shifted to the right by adding ZnO and Al2O3.