Advanced control of steam assisted gravity drainage (SAGD) process

点击翻译按钮获取中文摘要

Although the push for renewable energy and green energy is growing by the day, the demand for fossil fuels, such as petroleum, is still very high and has an upward trending forecast. Furthermore, of all the fossil fuels, the demand for petroleum is increasing as countries look to be coal free. However, with increase in the demand for petroleum coupled with high inflation in several world economies, the cost of producing it has also gone up significantly. This surge in production cost, coupled with slowly depleting conventional reserves and advancement in exploration and production technology have led to the birth of unconventional recovery technique, including steam assisted gravity drainage (SAGD). Steam-Assisted Gravity Drainage (SAGD) is one of the major thermal recovery processes used to extract the majority of the 1.7 trillion barrels of heavy and extra heavy oil (bitumen) from the oil sands of Western Canada. It involves, injecting superheated and around 80% saturated steam into the oil sands reservoir through an upper injection well to mobilize the highly viscous bitumen. Current commercial techniques to improve productivity by manual manipulation of steam injection pressure or rate and production rate of fluids have proved to be suboptimal, with recovery rates between 25 and 50%. Recent research on automating the process via Proportional-Integral Derivative (PID) control and more advanced methods like Model Predictive Control (MPC) , have proven to be an improvement over open loop methods of steam injection for oil recovery.Thus, the main focus of this research proposal is to develop a novel control scheme to manage a well pad with multiple well pairs and maximize production by adaptively adjusting steam delivery and production rate based on local geological and production factors in a reliable yet unsupervised manner. Thereby, transforming today's "passive" reservoir well into a "smart and proactive" one, ensuring maximum bitumen recovery with minimum usage of steam. The industrial partner, Spartan Controls Ltd. is the recognized leading provider of process control, measurement and automation solutions in the process industries in Western Canada, including oils sands. Their interest is to apply the developed advanced control strategies through this collaboration to improve short-term and long-term production, minimize steam consumption and consequently reduce environmental impact.