Global approach for calculation of minimum miscibility pressure

An algorithm has been developed for calculation of minimum miscibility pres sure (MMP) for the displace ment of oil by multicomponent gas injection. Th e algorithm is based on the key tie line identification approach initially addressed by Wang and Orr [Y. Wang and F.M. Orr Jr., Analytical calculation of minimum miscibility pressure, Fluid Phase Equilibria, 139 (1997) 101-12 4]. In this work a new global approach is introduced. A number of deficienc ies of the sequential approach have been eliminated resulting in a robust a nd highly efficient algorithm. The time consumption for calculation of the MMP in multicomponent displacement processes has been reduced significantly and can now be performed within a few seconds on a PC for a 15-component g as mixture. The algorithm is hence particularly suitable for gas enrichment studies or other case studies where a large number of MMP calculations is required. Predicted results from the key tie line identification approach a re shown to be in excellent agreement with slimtube data and with other mul ticell/slimtube simulators presented in the literature. (C) 1998 Elsevier S cience B.V. All rights reserved.