The Role of Diffusion and Dispersion in Miscible CO₂Injection in an Iranian Naturally Fractured Reservoir

Abstract

Miscibility is controlled by physical dispersion during miscible processes that comprise two parameters: diffusion and mechanical dispersion. Testing different dispersivities on one synthetic model then on a field case shows the existence of three regions at which each component of physical dispersion controls the miscible CO2 injection. Unfortunately, this parameter is usually ignored during simulating the miscible processes, but this study shows neglecting physical dispersion will highly affect the breakthrough time of displacing fluid. The results show the highest recovery for the process controlled by physical dispersion which could be an important result in designing a miscible process.