Oil-Recovery-Parameter Optimization by Air—Foam Injection into a Low-Permeability Light-Oil Reservoir

Abstract

The physical mechanism of air-foam flooding that was proposed earlier by other authors was studied using NB-95 foaming agent as an example. The parameters for air-foam injection in the T9 block of SY oilfield were simulated numerically optimized using the STARS module of the CMG reservoir simulation software. The experimental results demonstrate that the optimal injection-volume-to-production ratio for air-foam flooding in the T9 block is 0.8-1; gas-to-liquid ratio, 0.8-1; foaming agent concentration, 0.5-0.75%; and injection slug, 0.18-0.22 of the pore volume. Experimental physical simulation shows that air-foam flooding can enhance oil recovery by 25.85% and can be used to develop a theory of oil displacement by air-foam flooding.