Reza Masoomi - Department of Petroleum Engineering, KubSTU, Russia
Bijan Maleki - Assistant Professor, Imam Khomeini International University

WAG injection was proposed to improve efficiency of gas macroscopic displacement. This process can reduce the high mobility of gas phase in oil displacement process. In this study, usedmodel has an active aquifer that affects on the performance of WAG injection. Ultimate recovery of hydrocarbons increases with increasing both production and injection rates in the WAG injection process due to increased viscous forces which reduce the time for the effect of gravityforces that will cause fluid segregation. But in this study has been shown that increasing the viscous forces due to increased production and injection rates more than an optimal value, water coning phenomenon has been done because of existing active aquifer and finally has resulted inreduced ultimate hydrocarbon recovery. Also the parameters influencing on EOR process in WAG injection have been studied with compositional simulation methods in a model with an active aquifer. This model has been shown that the rate of water injection as a half-cycle is aneffective parameter such as the half – cycle gas injection in the WAG injection process.At the end in a real oil field after history match, WAG injection was simulated for this reservoir then compared with immiscible gas injection and natural depletion projects in a 25 years period.

WAG Process, Compositional Simulation, Active Aquifer, Sensitivity Analysis