Design of Dividing-Wall Columns by Mixed-Integer Nonlinear Programming Optimization

Dividing-wall columns (DWCs) offer an interesting alternative to conventional distillation towers. Savings of up to 30 % in both energy and capital cost are reported. While these high savings are realistic in some applications, DWCs offer less or no advantage at all in other applications. In any case, it is important to make a fair comparison between the conventional system and the DWC based on an optimized process design. Mixed-integer nonlinear programming (MINLP), especially the presented modified Generalized Benders Decomposition approach, could be the tool to make this comparison, as shown here.