Triple-column stacked side-stream distillation sequences
Journal
Applied Thermal Engineering
Journal Volume
295
Start Page
130706
ISSN
13594311
Date Issued
2026-05
Author(s)
Liu, Hsiao-Te
Abstract
Many energy-saving strategies have been proposed for distillation processes. Among these, a newly proposed configuration known as the stacked side-stream sequence (SSS) has emerged as a promising alternative, and has been shown to offer superior performance compared to the widely-studied dividing-wall columns (DWCs) in many cases. DWCs are most often applied to the separation of ternary mixtures, but there have also been many reports in the literature of DWCs being used to separate four or more components. SSSs also naturally generalize to the case of four or more components, but no studies of four component (three column) SSSs have been published. In this work three-column SSSs are designed for two illustrative case-study mixtures. The results in terms of cost and energy savings are compared with published results for the designs of DWCs for the same separation tasks. For the first case study, the best SSS was found to reduce the usage of energy and total annual cost (TAC) by 61.80% and 45.03% respectively compared with conventional sequences. For the second case, an industrially relevant hydrocarbon mixture, the best SSS was found to achieve a reduction of 60.93% in energy consumption and 50.32% in TAC. This result also compares favorably with the DWC, which was reported to accomplish a 46.9% decrease in TAC and a 58.0% decline in energy consumption. It can be concluded that SSSs should be considered among other alternatives for energy intensification when four or more components are to be separated by distillation.
Subjects
Distillation
Heat integration
Process design
Process intensification
Stacked side-stream sequence
Publisher
Elsevier Ltd
Type
journal article