Difficulties in Separation: A Unique Thermodynamic Approach

A mixture of hydrocarbons is modeled by the general cubic equation of state equipped with a set of mixing rules. Thermodynamic concepts within the model allow us to understand the separation process at the phase equilibrium level, which provide a major aid from the process design point of view. This thermodynamic model is employed in the design of a multi-column distillation process for the separation of a hydrocarbon mixture. Within the process integration of heat streams and the utilization of flash separators facilitate the utilization columns products in order to achieve optimum cost conditions. Computer aided simulation such as IDEAS & UNISIM are used to provide a sufficiently accurate application of the mixing rules that would enable the model to provide precise mixing behavior. Alternative designs are still being tested.