LIFE CYCLE ASSESSMENT OF URBAN WASTEWATER TREATMENT PLANTS

Abstract

This article analyzes the efficiency and environmental impact of four wastewater treatment plants (WWTPs) in different cities (A, B, C, and D) using the Life Cycle Assessment (LCA) methodology. The study focuses on key operational processes of WWTPs, by the seven days biochemical oxygen demand (BOD₇), total phosphorus (P_t), and total nitrogen (N_t) removal efficiency, electricity consumption, sludge management, and transportation. The results indicate that all analyzed WWTPs ensure high organic matter removal efficiency (>92% BOD₇); however, significant differences were observed in nitrogen and phosphorus removal rates. The life cycle assessment revealed that B and C WWTPs have the highest electricity consumption, directly contributing to a greater global warming impact. Sludge treatment was identified as the most significant source of environmental impact, particularly in eutrophication and acidification., with the greatest impact observed in the WWTP of city C. Improving treatment technologies, optimizing sludge management, and reducing energy consumption can significantly enhance the environmental performance of wastewater treatment plants. Future research should cover a wider range of treatment processes and incorporate long-term data analysis for more accurate insights into WWTPs' environmental impact.