Greenhouse Gas Emissions from Incineration of Municipal Solid Waste in Seoul, South Korea

Greenhouse gas (GHG) emissions from the incineration of municipal solid waste (MSW) have become a concern in the solid waste community from the perspective of climate change mitigation and response. In this study, we aimed to estimate the GHG emissions from the incineration of MSW in Seoul, with a population of about 10 million, by using the IPCC (Intergovernmental Panel on Climate Change) 2006 guideline and scenario analysis for 2030 and 2040. In 2021, Seoul generated 2899 kt of MSW/yr. Approximately 40% (1163 kt/yr) of Seoul's MSW was disposable (or non-recyclable) waste. Out of the disposable waste, about 741 kt/yr of combustible waste was treated by incineration, resulting in 545 kt CO2 eq emissions, which was about 7.5 times higher than the 74 kt CO2 eq in 2000. The dominant contributor to the GHG emissions was plastic waste, accounting for the largest fraction of 92% (501 kt CO2 eq/yr in 2021). Scenario analysis showed that if the current situation (BAU scenario) is considered, with the assumption of no reduction in MSW generation, the capacity of Seoul's four incineration facilities will be exceeded in 2029. All other scenarios (S1, S2, and S3) showed reduced amounts of MSW incineration and GHG emissions compared to the BAU scenario. Especially, S3 (waste reduction and increased recycling rate) revealed a 53% reduction when compared to the BAU scenario. Based on the results of our scenario analysis, it is expected that in 2040, the GHG emissions from incineration will be in a range of from about 389 kt CO2 eq to 832 kt CO2 eq, depending on the waste minimization policy and recycling efforts in the future. Strengthened regulations on and efforts towards plastic waste reduction and the recycling of MSW will be crucial with the perspectives of GHG emissions by incineration and resource recovery.