Simulation of Heat and Mass Transfer of a Co2 Binary Mixture, in the Miscible Conditions of a Supercritical Antisolvent Process

A complete description of the Supercritical Antisolvent Process requires the modelling of several complex physical phenomena such as heat and mass transfer, hydrodynamic, phase equilibria of ternary mixtures, and nucleation /growth of the specie to be precipitated; moreover, the description should also account for the biphasic case, where the jet of organic solvent breaks up as droplets. As a first step, we focus on the simulation of mass and heat transfer of a binary CO2-solvent mixture in miscible conditions, based on the pioneer work developed by Werling and Debenedetti. The system is described as a spot of pure solvent immersed in pure carbon dioxide, but compared to Werling’s work and further publications, we explore conditions where the temperatures of the solvent and the fluid are different; hence, our calculations allow to take into account the heat transfer in the mixture. The evolution of the spot size is detailed for various conditions of pressure and temperature, and for two CO2-mixtures.