This Demonstration computes the rectifying and stripping profiles (blue and magenta curves) for a fixed maximum number of plates in each section equal to seven stages. You can change the reboil and reflux ratios to see if the distillation is feasible (i.e., if the stripping and rectifying profiles intersect). The number of plates needed to achieve the separation is then easily obtained by counting the stages from the bottom stage to the intersection point and the stages from the condenser stage up to the intersection point ; the number of stages is . As expected for a ternary system, the global material balance around the whole distillation column is represented by a line shown here in green.