Polymer Flooding for EOR: Field Applications, Recovery Performance, Injectivity, and Scale-Up Lessons (2005-2025)

Polymer flooding is one of the most widely applied chemical enhanced oil recovery (EOR) technologies and has progressed from conventional onshore sandstone applications to increasingly challenging reservoir environments. This study reviews global polymer flooding experience from 2005 to 2025 using a curated database of 54 documented field applications, including injectivity tests, pilots, and commercial projects across sandstone, carbonate, unconsolidated, heavy oil, offshore, high-salinity, and high-temperature reservoirs. Field data, laboratory investigations, and reported operational experience were evaluated to assess injectivity behavior, polymer retention, viscosity stability, recovery performance, surveillance practices, and implementation outcomes. The reviewed projects span reservoir temperatures from 16 to 124 °C and salinities from approximately 500 to 270,000 ppm total dissolved solids. The analysis shows that successful polymer flood applications are consistently associated with effective mobility control, sustained injectivity, appropriate polymer quality, surveillance-supported reservoir management, and disciplined operational execution. Advances in ATBS-containing and thermally stable polymers have expanded applicability into harsher reservoir conditions, although many developments remain at the injectivity assessment or pilot stage. The resulting synthesis provides a field-based framework linking reservoir conditions, injectivity, polymer performance, surveillance, and operational execution to support screening, qualification, design, scale-up, and decision-making for future polymer flood developments.