A review of experimental methods for determining the Oil‒Gas minimum miscibility pressures

Abstract

An accurate determination of the minimum miscibility pressure (MMP) is required for the miscible gas injection project in oilfield. The experimental methods are usually considered to be an available and appropriate way to determine the MMPs, while so far few study has been found to systematically review and evaluate the experimental MMP determination methods. In this study, for the first time, ten existing experimental methods and their three important technical aspects, including the experimental design, operating procedure, and MMP criterion, are critically reviewed for determining the MMPs. Then, the three technical parts for each experimental method are specifically evaluated and scored from thirteen factors. On the basis of the evaluation results, a novel and effective screening table, which is coupled with the weight analysis, is initially developed to assist the selection of the most appropriate MMP experiment for different specific conditions. From the previously published studies, the conventional slim-tube tests, rising-bubble apparatus (RBA), and vanishing interfacial tension (VIT) technique are still the three most widely-used experimental methods for the MMP determinations. Results from this study indicate that the slim-tube and coreflood tests are the best experimental methods for the MMP determinations, which are followed by the RBA, VIT technique, and microfluidic test. Future work with respect to the experimental design, operating procedure, and MMP criteria are expected to improve the existing experimental methods and possibly initiate a completely standardized experimental method for the MMP determinations.