Numerical Simulation of Cooling Damage to High Pour-Point Oil Reservoirs

Aiming at the better understanding of cooling damage to high pour-point oil reservoirs,a numerical simulation was performed.The coupled multi-field equations solved by numerical method were used in describing the process of injecting cold water in high pour-point oil reservoirs based on the physical model of phase component in pores,governing equation of wax precipitation and the water-oil phase flow mathematical model and temperature field mathematical model.The simulation results show that the ratio of permeability after water flooding to the original is about 0.85 within 50 meters from injection well after 30 hours of water injection.The ratio of permeability after water flooding to the original nearby the injector wellbore is constantly 0.87 from the start of injection to 30 hours after injection.The cooling damage range extends from 15 to 93 meters as water injection time extends from 5 to 30 hours.The numerical simulation results of cooling damage to high pour-point oil reservoirs provide a theoretic base in their proper exploitation.