Trois, Cristina.Kissoon , Sameera.2025-07-022025-07-0220242024https://hdl.handle.net/10413/23804Doctoral Degree. University of KwaZulu-Natal, Durban.According to the Global Carbon Atlas, South Africa is ranked as the 14th highest greenhouse gas emitter globally (Global Carbon Atlas, 2021). The waste sector is estimated to contribute to 4.8% of the total emissions across the country according to the 8th National Greenhouse Gas Inventory Report of South Africa (DFFE 2021). It is estimated that 76% of the total municipal solid waste in South Africa is disposed of into landfill facilities (DFFE, 2021). Landfilling and waste management as a whole are regulated through the National Environmental Management: Waste Act and the National Waste Management Strategy (NWMS). In an effort to determine and reduce the impacts of various sectors􀂶 contribution to global warming, the South African National Department of Forestry, Fisheries and the Environment (DFFE) commissioned the Mitigation Potential Analysis (MPA) study. The MPA methodology was developed to guide major sectors such as agriculture, transport and waste among others in understanding their contributions to global warming as well as to propose mechanisms at a national level to reduce the impacts of key sectors on global warming (DFFE 2018). The purpose of this study directly aligns with the goals of the MPA in efforts to mainstream the discourse climate change in waste management decision making, through the development of a preliminary framework to guide greenhouse gas mitigation from waste management activities using a bottom up approach starting at municipal level. The overarching hypothesis of this study is that municipalities in South Africa are the main custodians of solid waste in the country and can therefore play a key role in the effective mitigation of greenhouse gases (GHG) in the waste sector. However, some of the major gaps identified in understanding the exact contributions of the waste sector on climate change is the availability of good quality data as well as the lack of funding, capacity and know-how at municipal level to conduct GHG emissions and mitigation studies. The main aim of the study is to determine the annual contributions of the organic waste fraction to climate change over the next 50-years in two case study municipalities: one district municipality representative of a district municipality at provincial level, and one metropolitan municipality representative of the 8 metropolitan municipalities of South Africa. A second aim is that to develop a framework in support of the strategy for the stabilization of climate change from the management of organic waste at municipal level. This was conducted through the identification of pathways for the diversion of the organic waste fraction of municipal solid waste in the selected case study municipalities using the currently available data and forecasting techniques. In order to achieve these aims, the objective of the study encompassed four key components: data collection; a waste stream analysis and identification of waste amounts; an assessment of carbon emissions and reductions from organic waste in the case study municipalities and lastly the development of a framework for a greenhouse gas mitigation strategy to achieve climate change stabilization. This study assessed the GHG emissions and emission reduction potential from the organic food waste fraction and the garden refuse fraction in the Garden Route District (GRDM) and City of Cape Town (CoCT) municipalities in the Western Cape, South Africa. These case study municipalities were selected based on their individual contributions to the total population of the Western Cape and their contributions to the provinces gross domestic product (GDP). The Waste Resource Optimization and Scenario Evaluation (WROSE) model is a life cycle assessment based model which assists the user in determining which integrated waste management scenario is most suitable, specific to a municipal􀁌􀁗􀁜􀂶s needs. This is based on the selection of appropriate technology pathways to divert waste from landfill as well as implement alternative waste treatment solutions. The study began with first advancing the WROSE model through the development of an algorithm to enable the model to perform long term greenhouse gas forecasting, This was done through the use of, waste generation data which was forecast in line with the total population growth. Using these identified figures and IPCC emission factors, the study assessed the potential GHG emissions and emission reduction achievable from the extraction of the organic waste fraction and garden refuse fraction in both case study municipalities. Thereafter, the study employed the WROSE model for the identification of appropriate mitigation pathways and alternative waste treatment technology options (Trois and Jagath, 2011 and Trois et al., 2023). The study further assessed the viability of the organic foodwaste fraction at varied intervals of recovery for use in applicable integrated waste management technology options such as landfilling with gas recovery and anaerobic digestion that are geared towards decarbonisation in the solid waste sector. A multicriteria decision analysis technique was incorporated for the development of the preliminary framework for climate change mitigation from municipal solid waste. In addition this study outlined a comparative analysis conducted between the two case study municipalities to determine how population affects waste generation and ultimately GHG emission contributions in the waste sector. The key finding is that existing municipal infrastructure is not designed for separated collection of the organic food waste fraction, nor is there existing infrastructure for the treatment of the organic waste fraction of municipal solid waste. Therefore, this study proposes a framework which adopts a phased approach to GHG emission reductions through the optimization of existing waste management facilities and the development of necessary infrastructure for the management of organic waste fractions over a 50 year period to achieve carbon emission reductions in the waste sector. This study developed a novel bottom-up framework for a greenhouse gas mitigation strategy that will contribute to climate change stabilization using immediate-term, short-term, mediumterm and long-term interventions that can be applied at municipal level in order to contribute to national emission reduction targets. This bottom-up approach is aimed at guiding the developments of individual greenhouse gas mitigation mechanisms at a local municipal level which contributes to the larger system of meeting NDC targets. The study is also the first application of a Tier 2 for the MPA approach which embodies national methodologies, in this case the WROSE tool as a country-specific model and IPCC emission factors to determine the GHG emissions and reduction potentials from the waste sector. These reductions can be achieved through the introduction of separated collection systems at local municipal level and technology options such as a material recovery facility, anaerobic digestion and composting in a staged approach. The framework will allow decision makers to develop a greenhouse gas mitigation strategy that will be applicable to the needs of the municipality based on existing infrastructure and available waste quantities which will ultimately contribute to meeting the needs of the NDC targets for South Africa using a bottom-up approach.enGreenhouse gas.Global Carbon Atlas.National Waste Management Strategy (NWMS).Thesis