AbstractsBusiness Management & Administration

CO2 Water Alternating Gas (WAG) EOR (Enhanced Oil Recovery) is a method to improve oil recovery by combining improvement in displacement efficiency from CO2 injection and improvement in sweep efficiency from injecting water in alternating sequence with CO2. This thesis focused on using the Ensemble Optimization method to improve the economics of this project in anonymous field X with discounted NPV (Net Present Value) as the objective function. The optimized variable is the injection BHP (Bottom Hole Pressure) for water and gas injection with fixed injection cycle of 6 months on each of water and gas cycle. The optimized result was compared with the result from the base case CO2 WAG with maximum injection BHP on each of the water and gas cycle and it showed promising result by optimizing the amount of injected water and gas on each injection cycle by controlling them from the injection BHP. Optimized strategy gave $ 30 million incremental in discounted NPV or equal to 4% increase in discounted NPV compared to the discounted NPV from the base case strategy contributed from higher oil production and better CO2 utilization than the base case.