Maximize the Ultimate Recovery by Designing and Optimising a CO2 Miscible Gas Injection Pilot in a Giant Carbonate Oil Reservoir, Abu Dhabi

摘要

is critical to properly design a CO2 injection pilot for its successful implementation. A detailed pilot design provides valuable information in field development decisions especially when managing high CAPEX. This paper presents detailed workflow of a miscible CO2 gas injection pilot design for a giant onshore oil reservoir in Abu Dhabi, UAE. A technical feasibility study was performed in over a two year period by Abu Dhabi National Oil Company (ADNOC), ExxonMobil, and Abu Dhabi Company for Onshore Oil Operations (ADCO). The key objectives of the study were to evaluate the CO2 EOR potential of the field, reduce performance uncertainty, and productively utilize a specific amount of CO2. A distinctive workflow was developed to identify the optimum pilot design that would successfully achieve these objectives. The project started with a comprehensive screening process to select a candidate reservoir and a suitable pilot location within this reservoir. A high definition representative sector model was then used to design the pilot. First, pilot well concept parameters such as well pattern, type, and orientation were selected to maximize oil recovery. Second, key subsurface uncertainties and design parameters were identified that would have the greatest impact on pilot performance. The Experimental Design technique was then used to evaluate these uncertainties. Finally, a deterministic simulation model was used to predict the expected range of pilot performance.