Optimization of slim tube coil length and injection rate for MMP estimation: A simulation approach

Enhanced Oil Recovery (EOR) is essential for extracting the large amounts of oil remaining in an oil reservoir after primary and secondary recoveries. Several methods of EOR are available and the use of each of these methods depends on the characteristics and properties of the oil and the reservoir. One of the most widely used EOR methods is gas injection, by immiscible or miscible means. For the miscible gas injection, it is important to define a property of the gas/oil system that is essential in planning a miscible gas injection, which is the Minimum Miscibility Pressure (MMP).;Determination of the MMP is essential for any miscible gas injection process to increase oil recovery from oil reservoirs. Several methods are available for MMP measurement. These methods can be either experimental, simulation or empirical correlations. Experimental approach is the most acceptable by the industry. Slim tube testing is much widely practiced than the Rising Bubble Method. However, slim tube lacks a standard agreed upon procedure. Coil length, coil diameter, injection rate and packing material are among those parameters still disputed.;In this study, MMPs measured from various configurations of slim tube experiments for lean gas with Abu Dhabi selected live oil are compared with simulated results. 1-D slim tube compositional simulation approach has been examined using CMG simulator. The impact of coil length and solvent injection rate on recovery factors and measured MMPs are examined. The optimum combination of these parameters of the slim tube apparatus suitable for the measurement of MMP is deduced. The simulator is also used to examine the miscibility behavior inside the slim tube's coil, a process not possible in experiments. Once a match is achieved between experimental data and simulated data, an investigation is conducted on the need for longer slim tube coil lengths in experimental procedures.;Accurate miscibility measurement is expected to contribute a great deal to the miscibility measurement optimization. In light of this study, data generated can be utilized to develop a criterion to prioritize Abu Dhabi oil fields for gas miscible flooding and remove the uncertainty related to the MMP measurements.