Multicomponent Distillation Column Design: A Semi‐rigorous Approach

Abstract A new semi‐rigorous approach for the design and simulation of multicomponent distillation columns is presented which combines a rigorous Naphtali‐Sandholm algorithm with Edmister's shortcut method. The column is assumed to comprise of single and multi‐tray units with the number of trays inside the multi‐tray unit treated as an iterative variable. The assumption of linear variation of flows inside a multi‐tray unit made by earlier workers (which often lead to convergence difficulties or erroneous results) has been replaced with a more rigorous calculation procedure. Examples are presented to demonstrate the usefulness of the new method for both design and simulation calculations. The semi‐rigorous model equations can be solved directly to obtain a reasonably accurate and practical design, whereas most other available methods require repeated calculations. Computer memory requirement is drastically reduced in this semi‐rigorous formulation as compared to rigorous methods.