Toward sustainable waste solutions : estimating GHG emissions in solid waste management : a case study of Pouso Alegre, Brazil, proposing scenarios based in Lahti, Finland

Abstract

Managing the resulting household waste in cities becomes essential as urbanization keeps increasing, with UN-Habitat forecasting that the global urban population will increase by 2.2 billion, reaching 68% by 2050. Since the waste sector generates around 5% of all anthropogenic greenhouse gas emissions, efficient waste management is critical to minimizing climate change effects. It is a fact that waste management becomes a crucial component of climate policies as cities grow. Without significant action, the IPCC forecasts global temperatures to climb by 1.1°C to 6.4°C this century. This study aims to evaluate and model the management of MSW in Pouso Alegre using advanced waste management strategies and technologies from Lahti, Finland, considering both countries' social, economic, and environmental differences. This study also brings light to the difference of waste management practices and challenges between North Hemisphere and South Hemisphere countries. This thesis uses a GHG calculator based on the LCA aproach to examine the effects of different proposed scenario alternatives on MSW treatment on GHG emissions in Pouso Alegre, Brazil. The study investigates landfills, incineration, anaerobic digestion, composting, and material recovery to identify the most effective technical options for minimizing greenhouse gas emissions. The objective is to select the most viable and sustainable solid waste management alternatives for Pouso Alegre, considering local situations and resource availability. Four scenarios for Pouso Alegre's waste management are examined in the thesis; each includes a variation of anaerobic digestion, controlled landfills, material recovery, composting, and incineration. On this basis, the potential of each scenario to decrease GHG emissions is being assessed. The present study stresses the importance of appropriate and effective treatment processes, prioritizing reducing or minimizing waste at source, and following the Waste Hierarchy. Maximizing recycling and composting activities becomes essential for lowering greenhouse gas emissions and preserving resources when waste output cannot be avoided. It connects waste management techniques to their effects on greenhouse gas emissions and the environment, offering suggestions for MSW management decision-makers. By using sustainable waste management techniques, cities like Pouso Alegre may dramatically lower their carbon footprint and promote a circular economy. The conclusions and suggestions are meant to stimulate more research studies and direct the formulation of policy, ultimately advancing a waste management strategy that is more ecologically conscious and sustainable.