Analysis of environmental factors and mechanism of metabolic shift of phosphorus accumulating organisms
LI Lu1,2,3, SHAO Hong-yu1, HUANG ji-hui4, NI Min1,2, HUANG Yong1,2, PAN Yang1,2
1. School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China; 2. National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Suzhou 215009, China; 3. Jiangsu Provincial Key Laboratory of Environmental Science and Engineering, Suzhou 215009, China; 4. Suzhou Drainage Co., LTD, Suzhou 215009, China
Abstract：Phosphorus accumulating organisms (PAOs) are the main functional microorganisms that play the role of phosphorus removal in the enhanced biological phosphorus removal (EBPR) process. Their metabolic behavior determines the stability of the phosphorus removal system and the final phosphorus removal efficiency. In order to adapt to the external environment change, the metabolic mode of PAOs will shift from polyphosphate accumulating metabolism to glycogen accumulating metabolism. On the basis of stoichiometric parameters, the mechanism of the metabolic shift of PAOs were described and the environmental factors that may cause the metabolic shift, such as influent phosphorus concentration, metal ions, pH value, temperature, etc. were summarized in this paper. Also, the reasons for the metabolic shift in different PAOs species were classified and described. This review provides a reference for the application of PAOs in EBPR processes.
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