Comprehensive analysis of greenhouse gas emissions and emission factors in a Korean domestic wastewater treatment plant: Insights into mechanisms and pathways for climate change mitigation

Abstract

This study aimed to estimate greenhouse gas (GHG) emissions from the Daejeon wastewater treatment plant (WWTP) in South Korea and identify strategies for reducing its carbon footprint. Both the worksheet-based Carbon Footprint Calculation Tool and the Massflow3 simulator were used to calculate the total GHG emissions from the “D” WWTP and identify the main sources of emissions. The results revealed that electricity consumption contributed to 45 − 48 % of emissions, while direct emissions from N2O accounted for 35–38 % of the total emissions. Furthermore, it was discovered that the WWTP's GHG emissions were 33–57 % higher compared to European sewage treatment plants that had established GHG reduction programs. To decrease the plant's carbon footprint, recommendations include optimizing nitrogen removal rates while minimizing incomplete nitrification and controlling the air flow rate in the aeration tank. Additionally, there is an emphasize on the importance of establishing a strategy to reduce indirect GHG emissions resulting from power consumption. These findings have important implications for the policy and management of WWTPs, highlighting the potential environmental and economic benefits of GHG emissions reduction.