Perpustakaan Digital ITB

The declining production from mature oil fields remains a critical challenge, as conventional methods recover only about 30% of the Original Oil in Place (OOIP). Surfactant–Polymer (SP) flooding, a Chemical Enhanced Oil Recovery (CEOR) technique, offers potential to improve recovery by reducing interfacial tension and increasing sweep efficiency. This study aims to calibrate a core-scale SP flooding model using laboratory experimental data and upscale it to field scale for production forecasting. A numerical model was developed in CMG-BUILDER, validated through history matching with CMG-CMOST, and simulated in CMG-STARS. The history matching reduced the simulation error from 32.8% to 3.5%, demonstrating accurate representation of waterflooding and chemical flooding behavior after adjustments to relative permeability and capillary number parameters. Fieldscale simulations were performed using a 5-Spot well pattern with heterogeneous porosity and permeability distributions. Sensitivity analysis of surfactant concentration and slug size revealed that longer slugs at lower concentrations improved recovery efficiency, with the optimal case (0.1% surfactant, 0.6 PV slug) achieving the highest recovery factor of 83.67%. These results confirm that slug distribution and sweep coverage are more influential than surfactant concentration once critical interfacial tension reduction is achieved. The integrated workflow from laboratory validation to field-scale simulation provides a reliable approach to evaluate SP flooding performance while minimizing uncertainties and costs prior to field implementation.