Mechanisms of the system and performance stability in enhanced biological phosphorus removal (EBPR) process

Abstract

Enhanced biological phosphorus removal (EBPR) process is a widely applied process to control eutrophication in the receiving water bodies. Compared to chemical precipitation-based phosphorus removal approach, EBPR is considered a more environmentally-sound approach because it employs the natural functions of biological processes with minimal chemical consumption and waste production. Although, there has been significant advances and research towards unfolding the EBPR mechanisms, important metabolic details still remain unclear due to the absence of any isolates of the key agents such as polyphosphate accumulating organisms or PAOs, and the lack of tools that allow for quantification of population and cellular level parameters in the EBPR system. These knowledge gaps hamper our ability to better design and control the EBPR process, as many full-scale EBPR facilities still experience unexplainable performance upsets. This study aims to develop a Raman microscopy method that enables quantitative evaluation of intracellular functional polymers in key populations, namely, PAOs and GAOs, in EBPR systems, and then to apply the tool to help elucidate the details of metabolic pathways and states within key populations and, to gain better understanding of the association between microbial population and intracellular status with system performance.