An Environmental Assessment of Municipal Solid Waste Management Strategies in Riyadh, Saudi Arabia: A Comparative Life Cycle Analysis

The environmental implications of various municipal solid waste (MSW) management systems in Riyadh, Kingdom of Saudi Arabia, were analysed considering the Riyadh Green Initiative through a comprehensive Life Cycle Assessment (LCA). This study evaluates five distinct scenarios: unsanitary landfilling (Sc0), incineration (Sc1), and a combination of technologies such as anaerobic digestion (AD) and a material recovery facility (MRF) in scenarios Sc2-Sc4. These scenarios were assessed using GaBi 9.2.1 software, employing the impact methodology outlined by CML (2001) to evaluate eight impact categories, including Global Warming and Acidification Potentials, among others. The findings indicate that scenarios incorporating the treatment of 100% of recyclable and organic waste through AD exhibited substantial environmental benefits. Additionally, Sc2 demonstrated the lowest environmental burdens across all impact categories. In contrast, Sc0 ranked the worst in all categories due to the absence of gas and leachate treatment. The results were shown to be reliable when compared qualitatively to previous studies. Furthermore, a sensitivity analysis was conducted to assess this study's system boundaries and the impact of the MRF rate. Overall, this research provides valuable insights for optimising MSW management practices in Riyadh, aiming to reduce their environmental impacts and align with the goals of the Riyadh Green Initiative.