Collections > Master's Papers > Gillings School of Public Health > An Evaluation of Biological Phosphorus Removal

Biological phosphorus removal (BPR) was examined to determine its feasibility as a phosphorous removal method for municipal wastewater. A literature search was conducted which reviewed previous research of the mechanism of phosphorus removal and the major biological phosphorus removal processes. A BPR experiment performed at the Mason Farm Wastewater Treatment Plant was reviewed and critiqued. The plant-scale experiment did not succeed because of 1) the presence of dissolved oxygen and nitrates in the anaerobic zone, 2) the low BOD concentration of the influent wastewater, and 3) the small portion of the return activated sludge which was treated anaerobically. A bench-scale BPR experiment was performed using the Mason Farm wastewater. The conclusions from the bench-scale experiment were that: 1) the release of phosphorus is an important step in the removal mechanism, 2) the phosphorus removing organisms may have a minimum requirement for organic carbon, and 3) a BOD concentration of greater than 200 mg/1 was needed for good phosphorus removal.