Key points:
- Chemical enhanced oil recovery (EOR) can extract an additional 10 20% of oil from an established reservoir following primary and secondary recovery
- Polymer flooding is an established chemical EOR technique that involves injecting an aqueous polymer solution into the reservoir to improve fluid mobility and boost extraction
- The rheological properties of the polymeric solutions used are crucial in defining their performance. For example, the viscosity of the fluid must be closely matched to that of the oil
- Detailed rheological characterization of the polymeric solutions used, under relevant conditions, supports performance optimization
Chemical enhanced oil recovery (EOR) using techniques such as polymer flooding can extract an additional 20% of the oil remaining in a reservoir following primary and secondary recovery. This article describes work carried out at TU Clausthal, Germany, to rheologically characterize polymer solutions for EOR applications. Understanding how any given solution flows and interacts with the pore geometry of the reservoir is the key to achieving beneficial performance.