Design of Petlyuk Distillation Columns Aided with Collocation Techniques

The use of shortcut methods for the design of complex distillation systems provides preliminary structures that need to be updated, typically by a recursive use of simulations. Although this procedure is generally effective, it can be time-consuming. In this work, collocation techniques are used as part of the design of Petlyuk distillation columns for the separation of ternary mixtures. Once a preliminary design is generated by a shortcut method, collocation techniques are applied to refine the location of the interconnecting and sidestream product stages, as well as the flowrate values of interlinking streams. The proposed method gives a proper distribution of stages for the Petlyuk system. The final designs are easily obtained with the proposed methodology, with a significant lower effort than that required when preliminary designs are corrected using recursive simulations.