An enhanced oil recovery polymer promoted microbial growth and accelerated microbiologically influenced corrosion against carbon steel

Highlights: • An oilfield biofilm consortium is grown in an artificial seawater medium. • Partially hydrolyzed polyacrylamide (HPAM) is utilized by the biofilm consortium. • HPAM promotes the growth of planktonic and sessile sulfate reducing bacteria. • HPAM utilization leads to 35% viscosity loss after 30 days of anaerobic incubation. • It also leads to higher weight loss and more severe pitting corrosion on C1018. - Abstract: Enhanced oil recovery typically relies on injection of seawater mixed with chemicals to increase reservoir pressure. A polymer such as partially hydrolyzed polyacrylamide (HPAM) is often added to increase viscosity. In this work, an oilfield biofilm consortium was found to utilize a commercial HPAM-based polymer. The polymer at 1000 ppm (w/w) promoted the growth of planktonic cells and sulfate reducing bacteria sessile cells in an artificial seawater medium during a 30-day incubation period in anaerobic vials. The polymer utilization led to 34.5% viscosity loss and more severe microbiologically influenced corrosion weight loss and pitting against C1018 carbon steel.