عنوان مقاله [English]
By increasing the extraction from the hydrocarbon reservoirs, the investment risks in the hydrocarbon field development projects reduces. Experimental analysis, generalization of their results, modeling and design the reservoir are used because of the uncertainty in geological issues during the preparation of dynamic and static models of the fields and the high cost of auditing these projects. Engineered water injection improves oil recovery, but the mechanism of its effect is not completely clear. According to the researches, one of the effective mechanisms of engineered water is the change of electric charge on the surface of oil and as a result, change of wettability. The effect of electric charge on the wetting behavior of carbonate rock which leads to harvest increase, has been investigated in this study. The existing surface complex models were reconstructed for the pure calcite rock model and the ionic composition used in this work. Models has been examined from the electric potential and surface absorption points of views and the best model was considered to predict zeta potential. Based on the obtained contact angles, 40 times diluted seawater increases the hydrophilicity by 30.79% compared to concentrated seawater. The results also showed that 40 times diluted seawater leads to a decrease in the zeta potential of pure calcite/brine from -2.9 to -5.4 mV and a decrease in the zeta potential of crude oil/brine from -6.2 to -18.3 mV. Based on the results, the electric charge of these two surfaces becomes more negative as the water salinity decreases and consequently the repulsive force between these two interfaces and the thickness of the blue film between these two interfaces increases. These changes lead to increase the water-friendliness of the rock, the greater tendency of oil for separating from the reservoir rock and ultimately lead to an increase in harvest.