Perpustakaan Digital ITB

Low Salinity Water Injection, also known as Smart Waterflooding, is a method for enhancing subsurface oil recovery using water. The method works by altering the reservoir rock properties from oil-wet to water-wet. Although proven effective, limited research exists on selecting the optimal parameters to achieve the best results. This study aims to identify the optimal strategy for implementing Low Salinity Water Injection. Reservoir simulations were conducted to analyze how variations in water salinity, injection timing, and injection rate affect oil recovery outcomes. The simulations utilized tNavigatorTM software and a Black Oil fluid model. A model of a mature oil field with 12.17 MMSTB of oil reserves was constructed. Simulations spanned 20 years across 37 different scenarios, varying water salinity from 18,000 to 1,000 ppm, testing five injection timing schemes, and adjusting injection rates from 100 to 800 STBD. Simulation results indicate that reducing water salinity consistently improves oil recovery; recovery increased from 24.05% to 30.00% as salinity was lowered to 1,000 ppm. However, reducing salinity below 1,200 ppm yielded no significant further increase in oil recovery. The study found that earlier and prolonged LSWI enhances recovery, while higher injection rates also boost recovery, they simultaneously lead to a sharp increase in water production. The optimal strategy identified involves using water with a salinity of 1,000 ppm, maintaining injections for 20 years, and employing an injection rate of 800 STBD. This strategy achieves an oil recovery of 31.26%, a 7.21% increase over high- salinity water methods. Nevertheless, an injection rate of approximately 400 STBD offers a better balance between oil recovery and the burden of water handling.