The mathematical model of the conversion of a landfill operation from anaerobic to aerobic

摘要

Transport phenomena equations were applied to develop a dynamic mathematical model to accurately describe the conversion of an anaerobic landfill to an aerobic bioreactor. The model equations were solved using the finite element method with the commercially available software COMSOL Multiphysics®. The initial aerobic bacteria concentration and heat of reaction were fitted with values in the range reported in literature. The consumption rate of oxygen and production rates of carbon dioxide and methane, and the growth rate of aerobic biomass were examined at a biomass concentration of 0.15 kg/m~3 and at a full scale landfill biomass concentration of 1 kg/m~3. Varying leachate injection rate was shown to be more effective for temperature control than changing the rate of air injection. This model provides a framework to determine how other factors such as pH or moisture content affect the conversion from anaerobic to aerobic conditions.