Upgrading a large wastewater treatment plant with the help of a large-scale pilot plant

A large scale pilot plant was designed and built and was run over several months in order to collect data and experiences for the final design of a 400.000 P.E. waste water treatment plant. The design and building of this pilot plant is explained with respect to the two objectives examination of plant performance and comparison of different treatment types. In two examples, concerning the influence of temperature and hydraulic balance on EBPR (Enhanced Biological Phosphorus Removal) process the results and their influence on the final design are described. Compared with a design according to the standard design rules in Germany (ATV-A131, 1991), the future large WWTP can meet the effluent requirements with 30% less volume. The costs for the pilot plant were less than 35% of the costs saved by the now possible reduction of tank volume.