Several Middle Eastern reservoirs are in advanced state of depletion and need new production and reservoir management strategies in order to meet the market demand. Several enhanced Oil Recovery (EOR) processes are employed to improve oil recovery in these reservoirs. One promising method which is applied in many of these reservoirs is CO2 miscible injection.
The Magwa Marrat reservoir is classified as a candidate for CO2 miscible injection although as yet this reservoir has not been significantly depleted. In order to investigate future management and production strategies of the reservoir, a small compositional sector model was developed. An optimization process for the WAG injection was then developed to obtain the optimum values of WAG ratio, slug size per WAG cycle, and total slug size. A series of simulation runs were performed to identify these optimum values.
After determining the optimum values, the performance of using horizontal wells was investigated and compared with the performance of using vertical wells. The result shows that the use of horizontal injectors in combination with vertical producers yielded better recovery in the reservoir than the use of vertical injectors.