Modelling of divided wall column

Abstract

The rectification is the most often used fluid separation technology. The improvement of the distillation equipment and process is significant (Haddad and Manley, 2008) because the rectification has relatively low energy efficiency. In practice, the aim is the separation of the multi-component mixture. This task can be solved with a number of columns depending how many components there are or one column with side product(s). This paper focuses on how to find a better structure with minimal energy consumption. The divided wall column (DWC) system is a promising energy-saving alternative for separating multi-component mixtures (Serra et al, 1999). The innovation of this equipment is a wall which divides the space in of the tower so the feed and the side stream-product zones are separated. This wall prevents contamination of the side stream by the feed stream. The dividing wall column has greater efficiency than common column sequence (Hernandez et al V, 2006). The conventional columns with side stream are also convertible to DWC. In this paper different constructions of the DWC were investigated with simulation experiments. The structure of the column was implemented in Aspen Plus TM simulator using the Radfrac unit of the software. The effects of the main parameters of the divided wall column like split ratio of the liquid and vapor stream, height of the wall, vertical position of wall, and the heat transfer of the wall were analyzed.