The application of polymer flooding as an Enhanced Oil Recovery (EOR) technology plays an important role in the recovery of crude oil from existing reservoirs. The polymer increases the water’s viscosity to enable higher interaction with the oil, achieving higher extraction from the reservoir during injection. Certain challenges arise after injection when a mixture of oil and polymer flooded produced water is obtained. This back produced water contains chemicals, including polymer, that has a direct impact on viscosity and viscoelastic properties resulting in 1) poor performance of conventional water treatment technologies and 2) null direct discharge into the sea based on low biodegradability of the polymer. This study aimed to evaluate a novel technology to enable treatment of produced water containing polymer effectively for reinjection or disposal purposes. Results showed that the reduction on viscosity requirements were met in a timely manner under aerobic and anaerobic conditions. Different operational parameters, including initial polymer concentration and temperature, were also investigated. Gel permeation chromatography (GPC) showed a lower molecular weight of the treated polymer compared to the untreated one. Finally, the treated polymer showed improved biodegradability compared to untreated polymer which translate to potential direct discharge into the sea in offshore applications.
Dr. Iris Porat
Miguel Pelaez, Kemira, Atlanta, Georgia