Study on methane fermentation using biological ethanol fermentation as pretreatment

Abstract

 The effect of pretreatment on methane fermentation of food waste by converting carbohydrate in the waste into ethanol using saccharification and ethanol fermentation was studied by batch and continuous experiments. The following results were obtained. (1) The substrate treated by ethanol fermentation had potential biogas generation equal to or higher than the control, and it was considered that the biodegradable component increased. (2) The methane concentration in the biogas increased by a maximum of about 20% and 15% in the batch and continuous experiments respectively compared with the control. (3) Ethanol degradation inhibition was confirmed for ethanol concentrations 2.0 g/L or greater. (4) Even under high initial concentrations, stable methane fermentation was possible because VFA generation was less than in the control. (5) The continuous experiment was able to operate stably for 50 days using the ethanol fermented substrate, and the volume of methane generated was same as the control.