Thin-layer Steam Distillation of Fermented Grains: Effects of Steam Flow Rate and Temperature

Bioethanol was obtained by distillation of solid-state fermented biomass. In this process, the objective material is ethanol and it is not necessary to consider other contents, like aromatic compounds, as essential in Chinese traditional alcohol distillation. In this paper, the characteristics of steam distillation of fermented grains were investigated and interpreted by means of steam drying. Two criteria were defined to evaluate the process unit energy consumption. The results indicated that the ethanol removal rate is improved with an increase of steam flow rate and the unit energy consumption is higher. But with an increase of inlet steam temperature, the constant distillation rate keeps invariant, and the unit energy consumption is lower.