Experimental and kinetic study on anaerobic co-digestion of poultry manure and food waste

Enhancement of biogas production by adding external substrates as a co-digestion material is one of the solution to increase energy self-sufficiency of the anaerobic digestion process. The aim of this work is to analyze the impact of anaerobic co-digestion of poultry manure with food waste on the biogas production. Experiments were conducted on a range of 0, 10, 20, 30 and 40% of poultry manure with 100, 90, 80, 70 and 60% of food waste (CD0, CD10, CD20, CD30 and CD40) respectively. Five laboratory scale batch reactors of capacity 2 L were used for this work. The solid concentration, pH and temperature values taken in all the reactors were 7.5% of total solids, 7 pH and 50 degrees C respectively. It was observed that the highest cumulative biogas yield of 8469 mL and methane concentration of 62.03% were obtained with the co-digested substrate CD30 (30% of poultry manure with 70% of food waste), whereas 7556 mL was obtained with raw food waste (CD0). The degradation efficiencies (TS, VS and COD) were also higher for CD30 compared to the other four substrates. First order kinetic model, modified Gompertz model and Logistic model were evaluated for the biogas yield and the predicted results were compared with the experimental results.