Deep water oil and gas resources play an important part in the energy mix of today's world, and ultra deep water oil and gas production has been the frontier of the oil and gas industry for the past decades. As the technological advancements push the limits of the industry's capability in the realm of ultra deep water exploration and production, more and more complexities are involved in the technical developments of these fields. Some deep water fields are identified as candidates for enhance oil recovery (EOR) methods. Very recently, several major deep water projects around the globe are including a miscible gas flood in their field development plan. Miscible EOR, combined with extreme conditions such as high temperature, high pressure, ultra deep water and reservoir depths, poses brand new challenges in production engineering designs.
This paper gives a summary of multiple challenges in the production lift performance for green field development of a gas miscible flood in deep water field. The authors have identified several key aspects in the nodal analysis methods that can potentially make significant impact on the accuracy of the predicted production lift performance for such fields. They include, among others, the characterization of fluid PVT (Pressure Volume and Temperature) and its implementation in nodal analysis tools, the use of fit-for-purpose vertical lift correlations, the implementation of compression constraints for gas injection, and the use of subsea pipeline rate multiplier as an approximation for subsea layout. Methodologies of resolving these challenges are proposed, and their limitations are discussed. This paper sheds light on improving the accuracy of nodal analysis of both injection and production for gas miscible EOR fields in deep water.