Feasibility and energetic evaluation of air stripping for bioethanol production

•Suitability of air stripping in Blenke cascade as mash separation method was tested.•Theoretical VLE calculations were carried out to confirm experimental data.•Energy input was simulated in ChemCAD and compared to conventional distillation. Stripping of mashes with air as stripping gas and low ethanol contents between 3 and 5wt% was investigated in terms of its suitability for continuous bioethanol production. Experiments in a Blenke cascade system were carried out and the results were compared with values obtained from theoretical vapour-liquid-equilibrium calculations. The whole stripping process was energetically evaluated by a simulation in ChemCAD and compared to conventional distillation. Therefore several parameters such as temperature, air volume flow and initial ethanol load of the mash were varied. Air stripping was found to be a suitable separation method for bioethanol from mashes with low concentrations. However, energetic aspects have to be considered, when developing a new process.