Assessing technical and economic efficiency in municipal wastewater treatment plants

This study evaluates the efficiency, implementation costs, and operational and maintenance expenses of various sewage treatment systems, aiming to identify solutions for improving treatment efficiency in cities with growing global populations and the increasing need for environmental pollution prevention. Seven sewage treatment plants (STP 1–STP 7) with different technologies were analysed. Factors, such as implementation costs, operational data, and pollutant removal efficiencies, were considered to assess the cost-effectiveness of each system, based on real-scale operations. The analysis revealed significant cost variations among the STPs, influenced by treatment methods, plant size, and construction materials. STP 1, which uses an activated sludge system, was the most cost-effective, with the lowest implementation, operational, and maintenance costs, and efficient pollutant removal. In contrast, STP 7, which uses upflow anaerobic sludge blanket followed by a submerged aerated filter, had the highest costs and lower cost-effectiveness. This study offers a comprehensive comparison of sewage treatment technologies, highlighting economic and operational trade-offs. The findings provide insights for stakeholders in selecting appropriate sewage treatment solutions, which are essential for sustainable environmental management despite urban population growth.