عنوان مقاله [English]
The minimum miscibility pressure (MMP) is a key concept in EOR by using miscible gas injection. In this report, MMP will be calculated by analytical and Parachor methods and the results are compared with experimental data. In the analytical method, initial and injection tie lines are determined by using negative ash calculations for both reservoir oil and injection gas. These tie lines will be corresponded with cross tie lines. MMP is the pressure where the length of one tie line (from initial to injection tie lines) equals zero. In the second method, MMP is calculated according to this fact; that interfacial tension between two phases goes to zero at completely miscibility. The interfacial tension is calculated by the Parachor model. Analytical calculations are performed by PR, SRK and MNM EOS. Results of analytical and Parachor methods are compared with the experimental data of slim tube and vanishing interfacial tension (VIT) methods. Results show superior agreement between calculations and experimental data. Our results indicate that MMP will be reduced significantly, due to the presence of intermediate components of reservoir oil in the injection gas and the similarity between reservoir oil and injection gas.