Wettability Alteration of Sandstone Oil Reservoir by Calcium Carbonate nanofluid

Different parameters play vital roles in oil and gas reservoirs recovery. Wettability is one of important factor that can have major effect on recovery. In this study, the effect of calcium carbonate nanofluid on wettability of sandstone reservoir was investigated. Oil aged thin sections were aged in different nanofluid concentration at 25. Effect of nanofluid on wettability alteration was studied by measuring contact angle (static, advancing and receding), surface energy, and wettability index. Results show wettability altered from strongly water-wet to strongly oil-wet after adsorption of nanofluid on rock. The optimum concentration is 0.025 wt. % that changes contact angle from 116.42 to46.99 and increased surface free energy from 10.86 to12.22 mN/m due to increase roughness on rock surface and wettability alteration index from 0 to 0.725 that indicates oil-wet tendency of rock.