Gasoil relative permeability at near miscible conditions: An experimental and modeling approach

Reliable relative permeability curves of oilgas systems are important for successful simulationand modeling of gas injection, especially when the miscibility condition approaches. in this work, therelative permeability of a co2-light oil system has been measured under different conditions, usingthe civan and donaldson (1989) [13] method. dolomite and sandstone core samples were used in theexperiments. the minimum miscibility pressure was calculated using an empirical correlation, as well asslim-tube simulation. due to some controversial assumptions of the civan and donaldson method, suchas immiscible and incompressible displacement, history matching was used for predicting the reliablerelative permeability of each phase at near miscible conditions. the civan and donaldson method wasused to predict the relative permeabilities as the initial guesses for the history matching. we found thatthe civan and donaldson method underestimates oil relative permeability. moreover, the effect of nearmiscibility on the gas phase relative permeability curve was stronger and the intersection point of theoil and gas phase relative permeability curves occurred at lower gas phase saturations. the results arehelpful for understanding near miscible relative permeability behavior and provide knowledge on fluidflow at low ift conditions during gas injection projects.