Abstract
In an azeotropic distillation column, the rate of net flow and the composition of net flow for both stripping and rectifying sections can be calculated from the limiting conditions of the separation desired. The pinch points are dotted on the radial lines starting from the point of net flow composition by trial and error, and locus of the pinch points are traced on the triangular diagram by the way of connecting the pinch points. Each minimum reflux ratio of stripping and rectifying sections can be calculated from the quantitative ratio of vapor and liquid of the operating line passing the point of intersection of locus line and feed line, and the larger of the two values shall be defined as the minimum reflux ratio of the system. For example, we illustrate the graphical calculation method for AcOH-H2O-BuOAc system and AcOH-H2O-EtOAc system.