New Operation Strategy for Separation of Ethanol-Water by Extractive Distillation

Extractive distillation with ethylene glycol represents the most competitive alternative for anhydrous ethanol production. The relative volatility of ethanol water decreases with solvent present at low ethanol concentrations. In order to carry out extractive distillation with high relative volatility, a new operating flowsheet is proposed including three columns: an extractive distillation column, s solvent recovery column, and a concentrator. The simulation of VLE and sensitivity analysis is performed on Aspen Plus software to obtain the best conditions and configuration for the new process with minimal energy requirements. The results reveal significant advantages in the reduction of energy requirements and an improvement in operation conditions compared with the conventional two-column process. Furthermore, the new process is more energy-saving with respect to other technologies.