Bench Scale Study of Fermentative Hydrogen and Methane Production from Food Waste in Integrated Two-stage Process

An integrated two-stage anaerobic digestion process has been investigated, which combined hydrogen and methane production for the treatment of food waste. With a none-heat treatment of inoculum, fermentative hydrogen production has been investigated at different organic load rate (OLR) in the first stage (hydrolysis/acetogenesis). The subsequent methane fermentation from the effluent of hydrolysis/acetogenesis phase was assessed as well. The maximum yield of hydrogen. (0.065 m(3)/kg VS. d) and methane (0.546 m(3)/ kg VS(.)d) were found at the OLR of 22.65 kg VS/ m(3.)d and 4.61 kg VS/ m(3.) d, respectively. Biodegradability test demonstrated that 2.98 % and 90.68 % substrate was degraded in hydrogen fermentation stage and the subsequent methane fermentation stage, respectively. Bench-scale test proved that the hydrogen fermentation coupled with subsequent methane fermentation was efficient and practical on the anaerobic treatment of food waste with none-heat treatment of inoculum.