Abstract :
CO2-WAG injection is able to increase efficiency in increasing oil recovery. This is proven by the increasing number of reservoirs around the world that use the Water Alternating Gas (WAG) injection method. The success of the screening criteria for the Water Alternating Gas (WAG) method can be determined by investigating the most dominant parameter in increasing the recovery factor (RF). This study aims to determine the parameters that have the most role in the recovery factor. This study uses a numerical simulator CMG GEM for reservoir modeling. Fractional factorial design method was used to check the reactivity of each WAG injection parameter. Reservoir modeling using a Cartesian grid and six parameters were tested, namely, the fractional factorial design with 16 runns. The most dominant parameter that can increase the value of the oil recovery factor in Water Alternating Gas (WAG) injection is the WAG Ratio with the smallest P value 2,90405 x 10-5 and the largest coefficient with a negative value of -3.12431. The second dominant parameter is porosity with a parameter value of 0.05 ? 0.1% with a P value of 0.000769113 and a coefficient of -2.00865. Number Of Cycle with a P value of 0.000827045 and a coefficient of 1.98728 in the range of 2-3 cycles. Meanwhile, Slug Size, Injection Rate and permeability are not significant parameters in this study based on a 95% confidence level.