Effect of different livestock dungs as inoculum on food waste anaerobic digestion and its kinetics

• Different livestock dung as inoculum for methane production from food waste digestion.
• Cow dung followed by piggery dung added reactors produced higher methane production.
• Kinetic studies showed the higher R2 and M value for cow dung added reactor.
• Highest volatile solids degradation was observed in cow dung added reactor.

The aim of this study was to evaluate the effect of different livestock inoculums on the anaerobic digestion of food waste (FW). Five different livestock dungs i.e., poultry dung (PD), goat dung (GD), cow dung (CD), piggery dung (PGD) and rhinoceros dung (RD) were utilized as inoculums and their effects were valued in various food to microorganism (F/M) ratios in batch reactors. Different livestock dungs achieved higher methane production and volatile solids (VS) reduction in different F/M ratios such as PD, GD, CD, PGD and RD achieved at F/M ratio maintained at 1.5, 2, 2, 1.5 and 1.5, respectively. The results indicated that CD and PGD inoculum were more suitable for the anaerobic digestion of FW than other livestock dungs. Reactors inoculated with CD achieved higher methane production (227 mL g−1 VS degraded) and volatile solids degradation (54.58%) at F/M ratio maintained at 2.