Simultaneous removal of organic and nitrogen pollutants in biogas effluent by A2O system

Abstract

Wastewater contains high content of organic and nutrients from livestocks is discharged to receiving water environment. Although wastewater are treated by biogas diggester, the effluent concentrations still remain very high in COD, amonium (NH₄⁺) and phosphate (PO43-). This research used a three-chambers system anaerobic- anoxic - aerobic (A2O) for simutaneous removal of organic, nirtrogen pollutants via continous experiments. The biogas effluents with COD (2000-5000 mg/L), NH₄⁺ (155 - 188 mg/L), PO₄^3- (13.00-21.95 mg/L) was used as influence for the continous experiments. The results show that removal efficiency of COD and NH₄⁺ were achieved at 82% and 70%, respectively. Removal of COD was met the safe level regulated by the QCVN 62-MT:2016/BTNMT. The inffluent contains high concentration of pollutants, thus a further study on operation condition such as hydraulic retention time and oxygen supply should be conducted.