(258e) Design of a Single Wall Divided Wall Column for the Separation of an Industrial Quaternary Mixture

Distillation is a phase creation process involving addition and removal of heat. The distillation of tertiary and quaternary component mixtures is done using two and three fractionating columns respectively. The Divided wall column (DWC), is a single shell distillation column which is capable of separating mixtures of three or more components into high purity products, thus eliminating reboiler duties for the remaining columns. The separation of a tertiary mixture using the DWC is a known technology and has widely been used for the separation of various tertiary component mixtures. Separation of a quaternary mixture using a single wall Divided wall column was attempted. In this paper we have simulated a Divided wall column for the separation of styrene, benzene, ethylbenzene, toluene mixture. The simulation of the DWC was done using four column arrangement in Aspen Plus chemical process simulator. By using DWC arrangement we achieved a purity of 98.26% styrene, 97.47% ethylbenzene, 95.74% toluene and 99.99% benzene. The stage wise pressure, temperature and composition profiles along with the sizing and costing of the DWC are discussed in the paper.