Re-Development of an Onshore Mature Oil Field to Double Gross Production by the use of Sensor-Equipped Electrical Submersible Pumps

Abstract

The objective of the field re-development project of the 16th Tortonian horizon in the Austrian Matzen field was to double gross production. To achieve this goal, some of the formerly used sucker rod pumps and electrical submersible pumps (ESPs) were replaced by high-rate ESPs. Over the course of two years, the field surface and subsurface upgrades were conducted, from the tendering process to the final installation. With the installation of downhole sensors, the foundation for a digital oilfield was implemented. Screening of the reservoir by a multi-disciplinary team generated suitable candidates for gross increases. Therefore, in the pre-project phase, the following steps were undertaken to prove the feasibility of such a large-scale re-development: Two viable candidates were selected as pilot ESP wells to prove the concept. Lessons learned from these candidates provided data for the scope of work of the ESP tender. In order to optimize the ESP operation, the wells were clustered into five groups. For each group one designated ESP type was chosen to cover the new required flow rate range. In two workover campaigns, 39 ESP installations were conducted, with the support of an onsite application engineer from the service company. The approach to double gross production by using high-rate ESPs proved to be feasible. The two pilot wells delivered critical information for the success of the project. Lessons learned regarding design and wellbore integrity were gained. A root cause failure analysis led to enhancements in material selection. By installing this high-volume artificial lift technology, the surface and subsurface infrastructure was refurbished to a new level of automation. This allows engineers to monitor, analyze, optimize, and troubleshoot the system in real-time, independent of location. A close cooperation between the service company and operator from the engineering to execution phase resulted in no early failure and exceptionally good run-life statistics. The sensor data are used to further improve the design and forecast equipment failure. This has a positive effect on economics by reducing the cost of the ESP strings and quantity of backup equipment. The concept of grouping wells was a very practical solution to conduct such a project in a very short time. A key for the smooth implementation of the project was the close collaboration with the service company's onsite application engineer.