Genetic algorithm for solving a gas lift optimization problem

Abstract

In this paper, we discuss a practical gas lift optimization problem for oil production. Artificial gas lift is a process of oil extraction where gas is injected into the oil wells to pump out the oil in the tubing. The total gas used for oil production is constrained by daily availability limits and limits on maximum injection volume into each well. The oil produced from each well is known to be a nonlinear function of the gas injected into it and varies between wells. The problem is to identify and inject the optimal amount of gas into each well to maximize the total amount of oil production from the reservoir on a daily basis. The problem has long been of practical interest to all major oil exploration companies as it has a potential of deriving large financial benefits. Considering the complexity of the problem, we have used an evolutionary algorithm to solve various classes of this problem. We have also introduced a multiobjective formulation which is attractive as it eliminates the need to solve such problems on a daily basis while maintaining the quality of solutions. Our results show significant improvement over the existing practices.