Title : Monod-based kinetic evaluation of biogas production from food-waste-derived substrates
Abstract:
Biogas formation from organic wastes depends strongly on microbial growth, substrate availability and hydraulic retention time. This study evaluates the fermenter reaction kinetics of a food-waste-based biogas production system using a Monod-type kinetic approach. The kinetic model used a hydraulic retention time of 160 days, a maximum specific growth rate of 0.45 h-1, a half-saturation constant of 0.08 g/L, a gas yield of 0.35 mol biogas per gram biomass, a microbial cell concentration of 1.2 g/L and a substrate concentration of 0.5 g/L. Based on these inputs, the microbial growth rate was calculated as 0.38793 h-1 and the gas production rate as 0.16293 mol/h. These values indicate that the microbial activity is sufficient to support biogas formation, while further optimization of temperature, pH, nutrient balance and substrate loading may improve gas productivity. The resulting kinetic indicators provide a quantitative basis for designing the first stage of an integrated biogas-to-Bio-DME process. The Monod-based evaluation provides an initial quantitative framework for the fermenter stage of the Bio-DME process. The calculated kinetic values can be used to guide experimental operation and to connect biogas generation data with downstream syngas and DME production models.
