Bioethanol Production by Crude Glycerol Fermentation

Abstract

An innovative biological process to produce ethanol and hydrogen from crude glycerol has been technically and economically assessed. Results shows an ethanol/glycerol yield of 1/3 kg/kg and a hydrogen/glycerol yield of 1/5 Nm3/kg. The cost of production of ethanol (without considering revenues from hydrogen produced) is in line with the market and was calculated to be about 0.35 €/liter. An innovative configuration for the fermentation section has been developed to allow ethanol and hydrogen production in a more cost-efficient way. The process developed is suitable to be installed in an existing biodiesel plant to produce a double counting fuel by valorization of a side stream such as crude glycerol.