Strategies for Evaluation of the CO₂ Miscible Flooding Process

Field experience has shown that CO₂ miscible flooding is an effective means to improve oil recovery. To evaluate whether a CO₂ miscible flood is suitable for a given field and the development of the optimal design requires considerable investigation and tests prior to a field-scale implementation. This paper proffers some guidelines for using a CO₂ miscible flooding operation so that the feasibility and profit can be optimized. The guidelines for evaluating whether a CO₂ miscible flood is suitable for a given field are developed and the procedure for a full implementation is summarized. These guidelines cover primary screening, laboratory measurements, reservoir simulation, economic analysis, pilot testing, and field application. Detailed methods also are presented for the optimization, well pattern and spacing preparation, and slug and injection process design. The work offers reservoir engineers a reference for decision-making in CO₂ miscible flooding.