Optimization of solid-liquid extraction of ethanol obtained by solid-state fermentation of sugarcane bagasse

Abstract

Solid-state fermentation has been used as an alternative to reduce the amount of waste water in ethanol fermentation. However, the recovery of ethanol from solid medium should be investigated, since depending of experimental condition used in the extraction, significant difference in the results can be obtained. In this work was investigated the influence of temperature (30-50°C), solid to liquid ratio (10-40 wt%) and orbital agitation (50- 180 rpm) in the recovery of ethanol from sugarcane bagasse at different fermentation conditions of moisture content (50-80%) and ethanol amount (5-20 wt%). The highest recovering efficiency was 81.3% at 30°C, solid to liquid ratio of 40 wt%, initial ethanol amount of 10 wt%, orbital agitation of 100 rpm and moisture content of 60%. The main contribution of this work was to demonstrate that the amount of water used in the extraction is lesser than that used in traditional liquid fermentation, making possible to obtain a more concentrated broth, saving with water treatment and energy for ethanol concentration.