An investigation on the applicability of Parachor model for the prediction of MMP using five equations of state

Miscible gas injection is generally used as one of the most efficient methods in the enhanced oil recovery. Minimum miscibility pressure (MMP) is an important parameter in the miscible gas injection projects, since local displacement efficiency in the reservoir media is highly dependent on the MMP. Therefore, an appropriate estimation of MMP would bring significant economic benefits. This paper presents a comparative study on five representative equations of state (EoSs) for predicting MMP using Parachor model together with the criterion of zero interfacial tension (IFT) at the miscibility conditions. The predicted MMP values are compared with the experimental data obtained from the most reliable measurement technique, so called slim tube method. Such a prediction would enables us to judge the accuracy of the results obtained from different equations of state as well as the capability of Parachor model to calculate the MMP. The results of predictions obtained for five oil–gas systems in this study reveal reliable MMP values within 5% of accuracy.

Research highlights▶ We examined five equations of states for the prediction of minimum miscibility pressure. ▶ We assessed the accuracy of Parachor model for the prediction of minimum miscibility pressure. ▶ Parachor model along with PR EoS and generalized volume shift correction can be used as a priori estimation tool for the prediction of minimum miscibility pressure.