Distillation Sequence Efficiency (DSE) Applied to Trains of Columns with Recycle Streams

Process modelling is usually simplified during chemical process analysis because it is less computing demanding and does not require so many parameters which are unknown at early stages of design. Fixing certain parameters to infinite allows to explore the process at its boundaries and the maximum attainable as indicator of the process potential. The infinity/infinity analysis assuming infinite reflux and infinite number of stages for the distillation columns trains is very useful for feasibility analysis. There are many methods in literature for distillation sequencing selection once the crude feed composition is defined. Most of them are very computing demanding and not applied to map all the feed compositions. A simple parameter called DSE (Distillation Sequence Efficiency) to rank the distillation sequences has been validated by comparing its results with the available computing demanding methods. Due to its simplicity and that requires only infinity/infinity analysis data and boiling temperatures, it has been applied to multicomponent mixtures with large amount of components. The goal of the present study is to show the potential of DSE method to solve trains of columns with recycle streams, being able to map all the feasible crude feed compositions.