Numerical simulation of foam flooding for sweep improvement.

摘要

Foams are used for mobility control in Enhanced Oil Recovery operations involving injection of gases or steam. The ability of foams to lower the mobility of vapour phase, under certain conditions, helps in reducing gravity override and channelling leading to improved sweep efficiency and hence oil recovery. A series of foam-flood experiments were carried out for implementing the process in a carbonate reservoir currently under miscible flood. The present research focuses on simulation of few of these experiments using empirical foam and reaction kinetics models with an objective of establishing parameters critical to field implementation.; The mobility reduction factor and the saturation at which the foam breaks down were studied using numerical models that simulated laboratory experiments. Effect of Surfactant Alternate Gas Injection (SAG) cycle, reservoir heterogeneity and economic aspects of the process were evaluated using a field scale numerical model validated by actual foam-tests. Foam flooding was found economically favourable in reservoirs with high permeability intervals near the top.