Maximizing Drawdown with a Novel Compact ESP Technology: A Case Study from Shushufindi Field in a Commingled Production

Abstract This paper presents an alternative solution to maximize oil production in a highly tortuous well under commingled production, by positioning a novel compact design of a Electrical Submersible Pump (ESP) between two reservoir intervals. Additionally, the strategy aimed to protect the formation face by placing the chemical injection point as close as possible to the bottom of the lower producing zone, thereby enhancing drawdown efficiency and chemical treatment effectiveness. To overcome the outlined challenges, an ultra-high-speed ESP system was installed between the perforations of two producing intervals. A tailpipe was deployed below the compact ESP to position a chemical injection disperser directly in front of the lower zone perforations, ensuring accurate treatment near the formation face. Specialized completion components, including tungsten carbide bearings and a multiphase gas handler, were incorporated to improve system reliability and mitigate premature failures. For the purposes of this paper, the designation "SHS-A" refers to the well selected for the implementation of the proposed solution. Due to the low productivity index of the SHS-A well, a standard ESP string of approximately 150 ft would have been needed to maximize production. However, installing such a long assembly posed significant challenges due to the high dogleg severity, particularly in the section between the perforated intervals, making proper placement difficult with standard configurations. The deployment of a compact ultra-high-speed ESP system—approximately 70% shorter than conventional strings—enabled installation within the limited space and was better suited for the tortuous trajectory. The optimized ESP placement resulted in a 45% increase in oil production, while maintaining the same intake pressure as a conventional ESP installed at a higher depth. This allowed for maximum drawdown and improved reservoir drainage. Positioning the ESP closer to the formation face enabled the use of a shorter tailpipe, placing the chemical injection disperser directly in front of the lower interval. This significantly improved the efficacy of the scale-inhibitor treatment. Additionally, the compact ESP design supports global sustainability objectives by reducing material consumption and operational waste. Installation time was reduced by 75%, minimizing rig time and associated environmental impact. This innovative solution successfully addressed the unique constraints of the SHS-A well and demonstrated the potential for scalable artificial lift optimization in similar high-tortuosity environments.