Comparison among the most frequently used systems for wastewater treatment in developing countries

The paper presents a series of tables, figures and charts which can be used for the preliminary selection of wastewater treatment systems, specially in developing countries. The systems analysed are: stabilization ponds, activated sludge, trickling filters, anaerobic systems and land disposal. Within each system, the main process variants are covered. A main summary table for quantitative analysis is presented, including easily usable information based on per capita values (US/cap, W/cap, m 2 area/cap, m 3 sludge/cap). Other tables for qualitative comparison among systems are also included, one based on a one-to-five-star scoring and the other on a balance between advantages and disadvantages of the main treatment processes. The sludge treatment and disposal is also covered, including a comparative analysis based on a scoring system.