Characteristics of Denitrifying Phosphorus Removal by Sequencing Batch Reactor
SBR工艺中反硝化除磷特性研究

The characteristics of denitrifying phosphorus removal were studied in a laboratory sequencing batch reactor (SBR) at NO3--N to COD ratio (NO3--N/COD) of 0.04, 0.095, 0.125 and 0.27, respectively. Experiments showed that the transformations of pollutants correlated well to control parameters (i.e. pH, ORP and DO). In blending phase, the reaction of denitrifying phosphorus removal could be indicated by ORP, and in oxidation phase a valley concentration of TN called NAS point could be monitored by all the three parameters, among which pH was the most sensitive parameter. Both reactor efficiency and effluent quality would be improved when supernatant was discharged at NAS point. In denitrifying phosphorus removal process, NO3--N was quickly transformed into intermediate products firstly and then gradually into N2 by denitrifying P-bacteria (DPBs). Carbon source had a significant influence on phosphorus removal capability of DPBs: when NO3--N/COD ratio was higher than 0.095, phosphorus removal capability of DPBs enhanced with the increase of the ratio. Results indicated that NO3--N/COD ratio should not be lower than 0.125 for a favorable denitrifying phosphorus removal effect.