Carbon footprint associated with four disposal scenarios for urban pruning waste

The inadequate disposal of urban pruning residues can cause significant environmental impacts. The objective of the study presented herein was to quantify the carbon footprint and analyze four disposal scenarios for the urban pruning waste of the city of Joao Pessoa (Northeast Brazil). Software SimaPro was utilized for the quantification of the carbon footprint, with the IPCC 2013 GWP 100y impact evaluation method. The end-of-life treatments considered were sanitary landfilling (with and without collection of methane), simple municipal incineration, and reutilization of wood (transformation into briquettes). The results indicated that simple disposal in sanitary landfill generated 136.34 kg CO₂/t urban pruning waste collected (highest carbon footprint), sanitary landfill with methane collection emitted 113.43 kg CO₂/t waste, municipal incineration generated 71.31 kg CO₂/t waste, and reutilization of woody residues was the scenario with the lowest carbon footprint, with 27.82 kg CO₂/t waste. This study demonstrated that reutilization of biomass, besides being environmentally viable, presents the potential to contribute to the city's environmental quality, including the possibility of being used to obtain carbon credits.