Co-digestion of Biowastes to Enhance Biological Hydrogen Process by Defined Mixed Bacterial Cultures

摘要

Co-digestion of biowastes for hydrogen (H-2) production using defined mixed cultures can overcome the high risk of failure due to contamination and imbalanced nutrient status. H-2 production from biowastespea-shells, potato peels (PP), onion peels (OP) and apple pomace, either individually or in various combinations was evaluated by hydrolyzing with defined hydrolytic mixed bacterial culture (MHC5) and subjecting the hydrolysate to mixture of defined H-2 producers (MMC6). Co-digestion of OP and PP hydrolysate supplemented at H-2 production stage with GM-2 and M-9 media resulted in 95 and 102l H-2/kg of Total solids (TS), respectively compared to 84l H-2/kg of TS in control. Upscaling the process by digesting 4.0l slurry (16-fold) resulted in 88.5 and 95l H-2/kg of TS, respectively compared to 72l H-2/kg of TS in control. Thus, H-2 production by co-digestion of biowastes could be improved through the supplementation with very dilute medium (0.1x) and selection of suitable biowastes under unsterile conditions. The overall efficiency can be further enhanced by integrating it with bioprocesses for biopolymers such as polyhydroxyalkanoates and or biofuels like methane production.