Process-Based Emission Modelling for Sustainability Assessment in Municipal Solid Waste Management: A Comparative Study

Abstract

Developments in Municipal Solid Waste Management (MSWM) systems depend on socio-cultural, political, economic, and environmental issues. The ability to assess and evaluate the level and nature of these relationships plays a critical role in measuring the performance level vis-à-vis sustainability of waste management systems. The current criteria adopted for assessing waste management performance do not capture an accurate and comprehensive representation of MSWM scenarios from collection to disposal. Hence the methodologies do not accurately measure the level of impacts resulting from waste management systems or, indirectly, the environmental, economic, social, and cultural costs of MSWM. This research develops a waste management performance assessment protocol that captures all relevant components of waste management processes. The methodology is based on emission as the indicator of choice for assessing the performance of a city-wide or regional waste management system. The study developed a framework, Comprehensive Emission Quantification Model (CEQ-Model), for measuring the sustainability of the MSWM system hinged on process-based emission modelling. This framework incorporated aspects of the Intergovernmental Panel on Climate Change (IPCC) Guidelines and Life Cycle Thinking (LCT), framed using carefully selected MSWM scenarios in New Zealand. In a ranked cumulative emission quantification assessment of four Territorial Authorities (TA), the research determined the performance level of each TA relative to others. Auckland Council, with a total emission of 4.272x1012 KgCO2-e generated from disposing of 2,425,022 tonnes of waste, was the most unsustainable territory, followed by Rotorua District with total emission of 6.666x10 10 KgCO2-e from 45,000 tonnes of waste, and Waikato District with emission of 5.380x10 10 KgCO2-e from 29,796 tonnes. In comparison, the most sustainable TA is Opotiki District with total emission of 2.314x10 9 KgCO2-e from 1,450 tonnes of waste, giving emission per tonne of waste per year as 1.762 GgCO2-e, 1.806 GgCO2-e, 1.6 GgCO2-e, and 1.481 GgCO2-e for Auckland Council, Waikato District, Opotiki District, and Rotorua District respectively.