Feasibility Study and Optimized Scheduling for Gas Recycling in a Gas Condensate Reservoir

Gas recycling is a generally accepted method to improve production from condensate gas reservoirs and has been welcomed due to its low cost compared with drilling new wells. The use of the net present value, which is both a factor of time and cost, is a reliable way of evaluating this process which considers the costs of injection facilities and production costs. It is important to find new methods for planning and optimizing gas injection. In this research, it has been tried to identify the optimal amount of gas recycling as well as the amount of gas produced by combining optimizers and reservoir simulators and using evolution optimization algorithms. It is worth noting that the method used in this study is based on a case study of gas recycling. The study shows that with the recycling of the entire production gas in the studied reservoir, the net present value could be increased from $ 126 million to $ 40 million. The production and recycling of a portion of the gas in an optimal form also increases the reservoir's life due to economic constraints from 10 years to 18 years. In addition, with a closer examination, it was concluded that due to the higher price of injected gas in cold seasons compared to the warm seasons, 65 percent of the gas produced can be returned to the reservoir in these seasons. By sensitivity analysis of the optimization results, the gas prices as well as the amount of gas condensate richness have significant effects on the optimal amount of recovered gas.