Investigation of ammonium removal in sequential batch reactor with anoxic nitrification-denitrification

Pollution from nitrogen-containing compounds discharged into water bodies from domestic, industrial, and agricultural activities is considered a major problem. Nitrogen pollution, especially high amounts of ammonium nitrogen, can increase oxygen demand and negatively affect aquatic life. Therefore, ammonium must be removed from water before discharge into surface waters. In this thesis, the ammonium nitrogen removal performance of anoxic nitrification-denitrification processes based on biogenic manganese oxide (BMO) and immobilized biogenic manganese oxide (IBMO) beads in sequencing batch reactors was investigated. The NH4-N concentration, cycle time, and C/N ratio in BMO and TBMO-containing media were varied from Period 1 to Period 9. Initial NH4-N concentrations were 10 mg/L and 15 mg/L in Period-I and Period-II, respectively. In Period-III, the NH4-N concentration was reduced to 5 mg/L. As a result of periodic operations examining the effects of cycle times, when reactors were operated for a 2-day cycle time, similar and more stable ammonium nitrogen removal efficiencies were achieved in all cycles. Higher TN removal efficiencies were also achieved. In experiments examining the effect of the C/N ratio, it was observed that removal efficiencies increased as the C/N ratio increased. Under conditions of 5 mg/L ammonium nitrogen concentration, 2-day cycle time, and C/N ratio of 15, removal efficiencies were 80% for BMO and 64% for TBMO. Successful results were also obtained in groundwater tests. In addition, membrane filtration was used as a final treatment at the end of the cycle in sequencing batch reactors and studies were also conducted to characterize the microbiology of groundwater.