Bioethanol production in membrane distillation bioreactor with permeate fractional condensation and mechanical vapor compression

Abstract

A membrane distillation bioreactor with permeate fractional condensation and mechanical vapor compression was developed for bioethanol production. Enhanced ethanol fermentation was achieved with ethanol in situ removal from the fermentation broth. Compared with the batch fermentation, the cell concentration in membrane bioreactor could be increased 26%. The deposited cells on the surface of the PTFE membrane led to membrane fouling. The membrane separation performance could be resumed by water rinse. High ethanol concentration of 421 g/L could be obtained by permeate fractional condensation with the process separation factor increased to 19.2. Mechanical vapor compression made the process energy efficient.