The Influence of Carbon Source Types and Nitrate on the Performance of the Enhanced Biological Phosphorus Removal Systems

The Influence of Carbon Source Types and Nitrate on the Performance of the Enhanced Biological Phosphorus Removal Systems by Shamim Ara Begum Dr. Jacimaria Ramos Batista, Examination Committee Chair Associate Professor, Department of Civil and Environmental Engineering University of Nevada, Las Vegas This research focused on two issues in enhanced biological phosphorus removal (EBPR). The first issue encompassed the effect of glucose and butyrate on the microbiology of EBPR. The second issue addressed the influence of denitrification on EBPR. The first issue was investigated in SBRs system fed exclusively with glucose and butyrate. The second issue was investigated in batch tests using wastewater and different levels of acetate and propionate. In the case of first issue, the phosphorus removal was negatively affected by glucose and effective by using butyrate as a sole carbon source. Fluorescence In Situ Hybridization analysis revealed that Candidatus Accumulibacter phosphatis (CAP), a PAO was not selected in the glucose fed reactor. However, glucose selected for Microlunatus phosphovorus, a PAO, Candidatus Compatibacter phosphatis (CCP), a GAO and Micropruina glycogenica, a GAO. In the case of butyrate, CAP and Defluvicoccus-rolated tetrad-forming organisms, a GAO were selected in the reactor. However, butyrate did not select for CCP. The % RA of GAOs and % P removal did not show good correlation in the butyrate fed reactors, which might indicate the presence of