Hydrogen production from food wastes by dark fermentation

Abstract

Biomass from various industries could be a source for biological hydrogen gas production where combination of waste treatment and energy production would be an advantage. This project studied hydrogen gas production from food wastes by dark fermentation. The objectives in this project were to optimize the pretreatment condition of industrial wastewater to enrich hydrogen producing bacteria and maximize the biological hydrogen gas production in food waste media. Bacteria source used in this project was industrial wastewater collected from FERMPRO Sdn Bhd. The pretreatment method used was heat pretreatment. The best pretreatment condition to enrich hydrogen producing bacteria in industrial wastewater was heat pretreatment for less than 2 minutes. Besides, the best fermentation conditions were pH 7 and 37 ºC. In the optimization, the effects of different food wastes which were rice, meat and vegetable on hydrogen gas production were tested in this research. Rice was used as carbon source, meat was used as protein source and vegetable was used as vitamin source. Three parameters which were rice concentration, meat concentration and vegetable concentration were tested. In optimization, RSM results indicated that important degree of three variables on hydrogen gas production was: meat concentration > rice concentration > vegetable concentration according to the F-value. In conclusion, the optimum concentration of each component in food media was 25.84 g/L rice, 24.21 g/L meat and 14.13 g/L vegetable to get the maximum hydrogen gas production 23.68 mL.