Predicting the Viscosity of Hydrocarbon Mixtures and Diluted Heavy Oils Using the Expanded Fluid Model

Abstract

The expanded fluid (EF) viscosity model was recently developed for petroleum applications. While petroleum fluids can be modeled as a single-component fluid, process calculations often require that the fluid be treated as a mixture of pseudo-components. For mixtures, the EF model mixing rules require binary interaction parameters, αij, between each component pair in the mixture, which are fitted to experimental data. In this study, a generalized correlation is developed for these interaction parameters as a function of the specific gravity and hydrogen/carbon ratio of the mixture components. The proposed correlation was developed on the basis of a data set that included viscosity and density literature data for pure hydrocarbon pairs at room temperature and atmospheric pressure and new data for pseudo-pairs of heavy oil/solvent at temperatures from 21 to 175 °C, pressures up to 10 MPa, and solvent contents up to 40 wt %. The correlation was assessed on a distinct test data set that included viscosity data...