Performance and Microbial Population in Side-Stream Enhanced Biological Phosphorus Removal Systems

The increasingly stringent limits imposed on wastewater effluent phosphorus demand for higher-level treatments through more reliable and better optimization of phosphorus removal processes. In this study, we evaluated the performance of four full scale wastewater treatment plants operating with a side-stream EBPR (S2EBPR) configuration. The S2EBPR process usually involves a side-stream anaerobic biological sludge hydrolysis and fermentation reactor, and it is a potential alternative to address the common challenge in EBPR related to weak wastewater influent. a suite of potential advantages. Three years of facility data were collected, and statistical analysis of the data, were performed to evaluate the process performance and compared with conventional EBPR. In addition, S2EBPR kinetics and microbial populations at the four facilities were investigated and compared to conventional EBPR systems. Facilities operating in an S2EBPR configuration tended to perform more reliably and were generally less affected by the influent BOD/P ratio. The microbial population observed at the four S2EBPR facilities indicated observable differences from those of conventional facilities, with high abundance of Accumulibacter PAOs and putative PAOs Tetrasphaera, and a very low abundance of known GAOs. The overall community structure also showed observable differences between conventional and S2EBPR facilities.