Real Time Control of Water Coning in Smart Wells

Production of undesirable water from oil wells is a serious problem in many oil fields. Commonly, water coning is responsible for the issue. This phenomenon may be causes in decreasing oil production rate, increasing water cut and consequently, high amounts of production costs that result in early well shutdowns. Conventionally, after water coning was occurred, the only treatment for this problem was reduction in production rate. This approach not only is time consuming and complicated, but also is low efficient one. In this work, we focused on a novel approach for prevention instead of treatment. We design a flow rate controlling mode in real-time manner instead of fasten the well after water cone breakthrough. For this purpose, first, a mathematical model derived to describe the physical shape of cone. Then we applied the rate controller to investigate the behavior of water cone growth in a smart well. It controls production rate as an inverse function of cone height in a closed loop. For this reason, height variation of water cone was monitored at bottom of the smart well. In this manner, oil production rate forcedly decreases while cone height increases. Finally, to find the optimum controller’s gain we used genetic Algorithm. This study revealed that height of cone could be controlled using nonlinear control approach. Simulation results show that in contrary to conventional method, the suggested method could reduce the coning height and operating costs considerably as well as improving oil recovery

کلیدواژه ها:

Water coning ، Control theory ، Undesirable water ، Smart well