Performance improvement of CO2 flooding using production controls in 3D areal heterogeneous models: Experimental and numerical simulations

3D experimental and numerical simulation results show that CO2 is displaced unevenly in the areal heterogeneous reservoir, leaving plenty of oil in the area of relatively low permeability. However, oil recovery of CO2 flooding in the areal heterogeneous reservoir can be doubled using production control treatments (sweeping area regulation, differential pressure control, or real-time producing regulation). The oil remaining in the area of relatively low permeability can be effectively displaced using sweeping area regulation, and both a larger sweeping area and a better CO2 flooding profile can be obtained using differential pressure control and real-time producing regulation. Through the analytical analysis of gas distribution and gas/oil mobility ratio, it is found that gas/oil mobility ratio is more sensitive to the areal heterogeneity, and real-time producing regulation has a powerful mobility control ability for CO2-EOR. Improvements in the performance of CO2 flooding using production control treatments provide a feasible technical strategy to treat with the areal heterogeneity and enhance the oil recovery for 5-spot well patterns in the areal heterogeneous reservoir.