초록
In this study, the ability of hydrodynamic cavitation pretreatment (HC) to increase ethanol yields at dry mill corn ethanol plants was investigated at pilot scale. Experiments were conducted at four HC energy densities, with and without jet cooking pretreatment and at a range of alpha-amylase (AA) doses. Corn slurries treated with HC had reduced particle sizes and significantly higher soluble saccharides. After simultaneous saccharification and fermentation (SSF), ethanol yields were 2.6% greater than in uncavitated controls. Jet cooking alone decreased ethanol yield compared to cavitated and control treatments. HC combined with jet cooking resulted in ethanol yields similar to controls. At alpha-amylase dosages 60% lower than those used at commercial scale plants (0.40% w enzyme/w dry corn), there was only a slight, insignificant reduction in ethanol yield. The net energy yield of HC was 47kWh in additional ethanol for each kWh used for HC. In conclusion, HC improved the solubilization of saccharides and ethanol yield from corn, and had a positive net energy yield, thereby improving the efficiency of dry mill corn ethanol production from both an economic and environmental standpoint.