Rapid Determination of Optimum Wettability Alteration Radius for Gas-condensate Reservoirs

The optimization in wettability alteration process is limited to the work of Zoghbi et al. (2010) and Fernandez et al. (2011). Although there are few investigations on the effect of treatment radius (Zoghbi et al, 2010), there is no reported data for the optimum wettability radius determination. In this paper a rapid method for prediction of optimum radius is presented and the effect of the wettability alteration radius on the cumulative gas production is investigated. A simulator has been developed based on the method suggested by Mott (2002) and the accuracy the simulator is verified by Eclipse (Schlumberger) software for different compositions. This developed simulator has been used for calculating the capillary numbers near the wellbore region before wettability treatment. The calculated capillary numbers are plotted verses a function of radius, based on the developed theory suggested by the authors, that relates the capillary number to radius. This method was applied for 27 synthetic reservoirs and the results were used for determination of optimum treatment radius, above which the increase in gas production is not significant. The optimum treated radius determined by this rapid method was in a good agreement with optimum wettability alteration radius based on the compositional simulations.