Vulnerable sides of cities aiming for carbon neutrality: contribution of wastewater treatment plants and landfill sludge disposal to greenhouse gas emissions

Environmental Science and Pollution Research. 2026. Vol. 33. No. 8. P. 3252–3265.

Dregulo A.

The present study focuses on greenhouse gas emissions from wastewater treatment and sewage sludge disposal at landfill. Traces of ammonium, dihydrosulfide, phenol, formaldehyde, various hydrocarbons, and mercaptans have been identified. The dynamics of these gases are especially intense during the purification process from grids to aerotanks. Methane concentrations fluctuated more than sixfold in the wastewater treatment cycle, while methane concentrations exceeded those of other compounds by more than 40–100 times. Greenhouse gas emissions from sewage sludge landfills were observed 10 years after cessation of unstable sludge disposal. The highest emissions occurred in the summer and autumn, accounting for up to 50% of annual emissions. The detected traces of pollution in the air near the border of the sanitary protection zone showed an increase in dihydrosulfide concentrations exceeding the maximum permissible concentrations (MPC). Results provide new insights into improving mechanisms for reducing greenhouse gas emissions both inside and outside the treatment plant site and for monitoring these emissions.

Keywords: air pollution, greenhouse gases, urban climate, sewage sludge, landfill, urban wastewater treatment facilities

Publication based on the results of: Socio-political, economic and ecological-climatic factors of sustainable development of territories in the context of global challenges (2025)