Single pot biovalorization of food waste to ethanol by Geobacillus and Thermoanaerobacter spp.

摘要

The current study was focused on developing a green thermophilic bioprocess to produce bioethanol from the food waste. The stored energy in food waste can be used for bioethanol production that can also help in reducing the land and environment impact of current food waste management processes. Geobacillus thermoglucosidasius was used to produce ethanol from food waste in a single pot at 60 degrees C. Scaling up the single pot bioprocess from 165ml serum bottles (165ml) to 1L bioreactor increased the ethanol yield from 3.03 g/L to 13 g/L. With scaling up to 1L reactor improved the substrate mass recovery from 39.2% to 92.8%. The ethanol production in 1L was further increased to 16.1g/L by the sequential cultivation of Geobacillus thermoglucosidasius and Thermoanaerobacter ethanolicus. Further, scaling up to 40L reactor gave an ethanol yield of 18.4 g/L and improved the ethanol productivity from 0.07 g/L/h (1L reactor) to 0.15 g/L/h (40L reactor). The sequential cultivation of thermophiles was able to produce ethanol from food waste without pretreatment, giving 70.1L of gasoline equivalent per ton of dry food waste. This is the first report of sequential cultivation of thermophiles for ethanol production using food waste and scaling up to pilot plant. (C) 2020 Published by Elsevier Ltd.