Experimental Column Profile Maps with Varying Delta Points in a Continuous Column for the Acetone Methanol Ethanol System

Traditionally, distillation column profiles have been divided into rectifying and stripping profiles, described by the liquid composition along the column. Recently, Tapp et al. (2003) defined a generalised column section and the composition profiles in these sections are described by the Difference Point Equation. Column sections can be sequenced by the designer (within certain constraints) and column profiles can be achieved that are neither stripping nor rectifying, allowing the designer much more flexibility. An experimental investigation has been undertaken for the acetone, methanol and ethanol system. By controlling the vapour and liquid feed compositions, temperatures, and flowrates, a number of column profiles at finite reflux were obtained. The results were compared with column profile maps predicted by the Difference Point Equation and found to be in good agreement. An interesting and counterintuitive prediction was that certain column profiles follow an inverse temperature profile, in that temperature decreases monotonically down the column. This prediction was verified experimentally and is highlighted in this work.