HYDROGEN AND METHANE PRODUCTION FROM STARCH PROCESSING WASTEWATER BY THERMOPHILIC TWO-STAGE ANAEROBIC DIGESTION
A two-stage thermophilic fermentation for hydrogen and methane production from wastewater of cassava rice and corn starch at different concentration (5,10 and 15 g/L) was studied. The hydrogen production from cassava starch at concentrations of 5 g/L gave the highest hydrogen yield and followed by cassava starch at a concentration 10 g/L, rice starch at concentrations of 15 g/L. The hydrogen and methane yields from cassava starch processing wastewater by two-stage was 81.5 L H2 kgCOD-1 and 310.5 L CH4 kgCOD-1, respectively with total energy yield of 13363 kJ kgCOD-1. Mixed hydrogen and methane (biohythane) production was 9.51 L biogas l-1 with containing of 55% CH4, 11% H2 and 34% CO2.