| Summary: | This study aims to undertake a comprehensive analysis of different waste management systems for the wastes produced in Östersund municipality of Sweden with an impact assessment limited to greenhouse gas emissions and their total environmental effects in terms of global warming potential, acidification potential, and eutrophication potential. A life cycle assessment methodology is used by integrating knowledge from waste collection, transportation, waste management processes and the product utilization. The analytical framework included the definition of functional unit, system boundaries, complimentary system design, waste management, and partial use of the energy. Three different municipal solid waste management scenarios, incineration, composting, and digestion were considered for the study. All wastes from Östersund municipality were classified into biodegradable and combustible and thereafter treated for energy and compost production. Greenhouse gas emissions and total environmental impacts were quantified and evaluated their corresponding benefits compared to three different types of marginal energy production system. The results showed that the major greenhouse gas carbon dioxide and nitrous oxide emissions are greater in composting scenario, whereas methane emission is greater in digestion scenario. Composting scenario that uses additional coal fuel has greater global warming potential and acidification potential compared to other scenarios. Composting scenario using wood fuel additional energy has greater eutrophication potential. The highest reduction in global warming potential is achieved when digestion scenario replace coal energy. The greater reduction in acidification and eutrophication potential achieved when digestion scenario replaced coal energy, and wood fuel respectively. Based on the assumptions made, digestion scenario appears to be the best option to manage solid waste of Östersund municipality if the municipality goal is to reduce total environmental impact. Although there may have plentiful of uncertainties, digestion and incineration scenario results are competitive in reducing environmental effects, and based on the assumptions and factors used for the analysis, the results and conclusions from this study appear to be strong. Key words: Solid waste, incineration, composting, digestion, total environmental effect, wood fuel, biogas.
|
|---|
