INVESTIGATION OF CO_2 FLOODING POTENTIAL IN THE JATIBARANG FIELD, A SIMULATION STUDY

摘要

CO_2 flooding acts as an effective Enhanced Oil Recovery method by reducing the remaining oil in the reservoir through several mechanisms (swelling, viscosity reduction, crude vaporization and miscible displacement). The viability relates mainly to the availability of CO_2, the structure complexity, and finally the achievement of the Minimum Miscible Pressure (MMP). In the Jatibarang Field, it is not an issue of CO_2 availability since CO_2 sources are available in the field itself, and near by fields.rnThe Jatibarang Field primary recovery is only 16.2%, and the current reservoir pressure is as low as 500 psia. The reservoir performance shows the driving mechanism in this zone is very weak water influx. Therefore a waterflood and/or Enhanced Oil Recovery Program need to be evaluated to increase oil recovery.rnBased on the screening criteria for oil fields in West Java, there are several possible CO_2 flood candidates, one of which is the Jatibarang Field. A fluid compatibility test was conducted using Jatibarang Field fluids, from current to initial conditions. The fluid properties of current and initial conditions were compared and analyzed using numerical simulation. Then an appropriate fluid model was selected to represent the reservoir conditions. Regression and fine-tuning of the equation of state resulted in the fluid characterization for this study. Tuning of the EOS should give a fluid model that closely matches the lab test results.rnReservoir pressure is very important when it comes to designing CO_2 floods, as it is usually far below thernMMP, as was the case in the Jatibarang Field. Based on the fine tuned fluid model, several CO_2 processes (immiscible and miscible flooding) were evaluated for the Jatibarang Field. These also included evaluation of different compositions of the CO_2 gas.rnTo evaluate the best recovery from CO_2 injection, a compositional numerical simulator was used. The amount of oil recovered was evaluated for different kinds of injection fluid.