Evaluation of hydrogen and methane production from co-digestion of chicken manure and food waste

Abstract

Recently, the rapid expansions of agricultural waste, including chicken manure and food waste, has increased the amount of organic waste produced. Therefore, the main objective of this study is to evaluate the possibility of using the co-digestion of food waste and chicken manure for the production of biogas, hydrogen and methane. An anaerobic co-digestion of chicken manure (CM) and food waste (FW) was carried out using a 150 mL serum vial at different ratios: 0:1,1:9, 2:8, 3:7, 4:6, 5:5 and 1:0 of CM to FW, and incubated at 35°C. The highest hydrogen and methane yields were 239.2 and 60.8 mL/gVS, respectively, for the experiment conducted at a selected ratio of 3:7 of CM:FW by using a 500 mL reactor. Tagged 16S rRNA gene pyrosequencing analysis for selected ratio 3:7 of CM:FW showed that the seed culture was comprised largely of uncultured bacteria from phyla Proteobacteria, Bacteroidetes and Firmicutes. During mesophilic hydrogen fermentation, phylum of Firmicutes (40%) was dominant at day 1, while phylum of Firmicutes (15%) dominated at day 13. Clostridium sp. was the main species detected in the acidogenic phase, while Methanosaeta consilii and Methanosaeta hungatei were detected during the methanogenic phase.