Simulation Study Of The Effect Of Smart Water On Relative Permeability During WAG-CO2 Injection For Light Oil Reservoir

Water alternating gas ( WAG ) injection with its first successful field pilot application on the North Pembina field in Alberta, Canada in 1957, is one of the most prominent EOR methods that substantially prolong the lives of the otherwise depleted and uneconomical oil fields. This technique is well established but the practical challenges are often of the occurrence of viscous fingering, gravity segregation and gas channeling or override and consequently, lower oil recovery rates. Previous researches have focused almost exclusively on modifying the salinity and the ionic composition of the injected water, also termed as smart water flooding which proved to further enhance the oil recovery obtained from water flooding. However, the use of smart water in WAG-CO2 process has not been studied sufficiently and requires further detailed study. As such, the approach of fine tuning the salinity of the injection brine during WAG-CO2 process is proposed in this project. This research aims to evaluate the impacts of smart water injection on the oil/ water relative permeability curves in comparison with the conventional brine during WAG-CO2 injection for light oil reservoir using reservoir simulation. This research also intended to systematically investigate the effects of the composition of Ca2+ and Mg2+ ions in brine on the oil recovery factor and to determine the optimum brine salinity for maximum oil recovery. Crucially, the simulation results are to offer valuable insights into the two phase relative permeability functions important to predict the behaviour of the fractional flow, fluid distributions, residual fluid saturations and oil recovery.