Multi-Criteria Decision Support for Flexible Dividing Wall Distillation Columns

In the design of a dividing wall column, different decisions have to be made. Some of these decisions relate to the column’s actual design and layout, which cannot be altered once built. On the other hand, decisions related to the column’s operation can, to some extent, be adjusted later. During the design phase, both layout and operation can be optimized to achieve an optimal column performance. However, this optimal performance depends on the process demands. If demands change later, we might lose the optimal performance. The goal is to make decisions that minimize these losses and are flexible across different demands.In this paper, we present a methodology based on a multi-criteria approach. We quantify the flexibility of a decision by comparing a Pareto front, which only optimizes the operating variables, to an ideal front that optimizes both layout and operation simultaneously. We introduce a flexibility indicator based on this difference and apply our methodology to an example mixture separated in a dividing wall column.