Computers & Chemical Engineering, Vol.110, 93-105, 2018
A cost-effective retrofit of conventional distillation sequence to dividing-wall prefractionator configuration
A dividing-wall prefractionator configuration was investigated for a safe and economic retrofit of the conventional sequence using simple distillation columns. In the proposed retrofit configuration, the first column was modified to a dividing wall column as a prefractionator to supply prefractionated multi-feeds to the subsequent column. To investigate the effectiveness of the proposed configuration, nine near-ideal feed mixtures were considered for analysis. The proposed configuration was then compared with several other alternative configurations. The proposed dividing-wall prefractionator efficiently generates prefractionated multi-feed streams avoiding feed mismatch and remixing effect with low modification cost. Moreover, because the proposed retrofit configuration allows for flexible switching between the dividing-wall prefractionator and the conventional operating mode, a safe retrofit is also ensured by reducing the operational risks. Several industrial retrofit cases were studied to validate the proposed dividing-wall prefractionator configuration. (c) 2017 Elsevier Ltd. All rights reserved.