This paper studies a WAG process for improving the recovery efficiency in light oil reservoirs. Until now, few references have reported the role of CO
mole percent on recovery improvement in light oil reservoirs. The injected gas was changed, and the effect of composition changes on performance of core flood experiments were conducted at fixed flow rate. Five series of experiments (varied in methane mole percentages, 0, 25, 50, and 75, 100) were systematically examined. The results indicated that the oil recovery efficiency improved with the increasing of CO
mole ratio and there was also maximum recovery efficiency in this work. That would be helpful to better understanding the role of CO
mole percent on performance of WAG injection in light oil reservoirs.
Keywords: experimental, WAG injection, hydrocarbon-CO 2 mixture, WAG ratio, effect of CO 2 mole percent