A shortcut design method for complex distillation structures

Distillation is by far the most common fluid separation method in the chemical industry, and its design is routinely conducted using commercial design software, often based on initial shortcut calculations. Whilst simulation and optimisation of simple distillation systems are fairly straightforward, the design of more complex structures, such as dividing wall columns (DWC), can prove problematic due to failure to initialise or to converge, and no adequate shortcut methods exists for these structures. In this work, a novel shortcut method is presented which can solve the shortcut design problem simultaneously also for complex structures using a simple optimisation procedure without the need for iterative manual calculations. The method is illustrated by four case studies. The shortcut design variables obtained using this method can be used to initialise rigorous simulation or optimisation problems, thus greatly reducing the risk of initialisation failure or convergence issues, also for very complex structures.(c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.