Real Time Optimization of a Natural Gas Lift System with a Differential Evaluation Method

Abstract

This article presents a method for optimizing and controlling an oil production system using a natural gas lift concept. Ever increasing development of Smart Well technology and various applications of down-hole monitoring and controlling instruments along with new methods of data acquisition/transmission make it possible for the natural gas lift system to be controlled and optimized more effectively and faster than before. With this technology it is possible to monitor the down-hole conditions of gas and oil zones and to control the inflow valves in gas and oil zones. In this work, a proportional integral differential feedback controller has been used to smartly control the entrance of gas from the gas zone to the oil well. The optimizer determines the optimal values of gas injection setpoint for the controller to manipulate the inflow of gas to the oil reservoir. The problem will be more complex when the available gas in the gas zone is limited. The optimization of this process has been done by a Differential Evolution method.