Kinetic analysis of landfill stale garbage (LSG) pyrolysis and combustion behaviour using thermogravimetry coupled MS and FTIR technique

Abstract

The environmental impact of landfill stale garbage (LSG), particularly concerning methane emissions and the depletion of valuable resources, presents a significant challenge to environmental sustainability. This research examines the thermochemical properties of LSG, establishing a foundation for the development of efficient treatment methods focused on energy and resource recovery. The TG-FTIR-MS technique and the modified Coast Redfern model were used to evaluate thermal behaviour, gas emissions, and decomposition during the pyrolysis and combustion processes of LSG, both individually and in blends. The study demonstrates that blended component pyrolysis attains a conversion efficiency of up to 85 %, in contrast to 65 % for individual components. This indicates a synergistic effect that implies catalytic actions, which notably improve the decomposition process and decrease pollutants such as sulphur, fluorine, nitrogen compounds, and hazardous halogens that may generate dioxins and furans during combustion. Analysis indicated that the activation energy necessary for the pyrolysis of individual LSG components exhibited significant variation, with values ranging from 7.6 to 217.3 kJ/mol. The blended components demonstrated an activation energy range of 20–178.5 kJ/mol for pyrolysis and 14.1–167.7 kJ/mol for combustion. This study suggests that pyrolysis of blended LSG components is preferable to combustion, as it offers greater efficiency and reduced pollutant emissions, despite combustion's notable energy yield and volume reduction. Our research indicates significant advancements in conversion efficiency and pollutant reduction, prompting a strong recommendation for pyrolysis as the optimal method for LSG treatment. This method demonstrates a balance between resource recovery and environmental responsibility.