Multi-objective optimization of the intensified extractive distillation with side-reboiler for the recovery of ethyl acetate and methanol from wastewater

•The suitable entrainer is screened via the thermodynamic insights.•Development of intensified extractive distillation with side-reboiler.•Optimization of proposed process using multi-objective particle swarm algorithm. This work explores the recovery of ethyl acetate (EtAC) and methanol (MeOH) from wastewater stream using three different extractive distillation (ED) processes, i.e., the triple-column ED (TCED), four-column ED (FCED), and the energy-intensified TCED with side-reboiler (TCED-SR). All the three processes are conceptually designed and then optimized using multi-objective particle swarm optimization with total annual cost (TAC), CO2 emission, and process route index (PRI) as objectives. Altogether, the TCED-SR is recommended to provide the best economic and environmental performances, as reflected by the lowest TAC and CO2 emission. It provides 34% and 20% lower TAC relative to TCED and FCED, respectively. Additionally, the CO2 emission is 39% and 17% lower with respect to the TCED and FCED. In the places where safety requirement is strictly regulated, the FCED is recommended since the PRI for the TCED-SR is high, which denotes that the process should be operated with care. However, the TAC and CO2 emission for the FCED is higher by about 21% and 36% with respect to the TCED-SR while it is lower than the TCED by about 20% and 17%, respectively.