Field B Oil Recovery Improvement Through Autonomous Inflow Control Device (AICD), A Case Study

Abstract

In a thin oil column environment, the team needs to look for a way to monetize this oil with optimized cost and reduce the risk of unwanted fluid (gas and oil). To make matter worse, the reservoir drive mechanism is mainly gas-cap expansion with moderate aquifer support. The team has looked at several methods to delay this water breakthrough i.e., standoff from Oil Water Contact (OWC) and Gas Oil Contact (GOC), and Autonomous Inflow Control Device (AICD). There are two AICD types considered during the preliminary design stage which are the Fluid Diode Type and Rate-Control-Production (RCP) type. The team performed a cost-benefit analysis on these two types of AICD. AICD RCP type was selected to be the best way forward for this kind of reservoir. AICD RCP type should be able to control the horizontal drawdown thus reducing the unwanted fluid production. With this type of AICD, the viscosity contrast between oil and the unwanted fluid is important. With the viscosity contrast of 0.6 cp for oil and 0.5 cp for water, the viscosity contrast is considered low. The AICD does not work effectively to reduce water production. Thus, it is important to have a good OWC standoff to delay water production. Coupled with the reservoir dynamic model, sensitivity analysis was performed with several cases to improve the team's understanding of the AICD impact on the oil recovery. Below are cases run to ensure the best configuration were applied for each completion. Gas Oil Ratio (GOR) impact on the oil recovery with and without AICDWater Cut impact on the oil recovery with and without AICD.OWC and GOC standoff impact on the oil recovery with and without AICDNumber of AICD joints impact on the oil recovery with and without AICD The utilization of AICD technology is predicted to significantly improve oil recovery with the expected reserve to increase around 10-25% while delaying the unwanted fluid production. The field has an existing Inflow Control Device (ICD) well and 2 AICD wells just completed in 2022. With this, the team may analyze the benefit of the AICD compared to ICD. In addition, to ensure good recovery from the reservoir, a mud breaker was pumped to reduce the drilling mud damage in the open-hole section. Furthermore, oil and water tracers were installed to ensure water production location on the AICD open hole section.