Removal of COD and Color from Anaerobic Digestion Effluent of Livestock Wastewater by Advanced Oxidation Using Microbubbled Ozone

Ozone-based advanced oxidation was applied for the treatment of anaerobic digestion effluent of livestock wastewater. Initial COD and color value were 930 mg/L and 0.04, respectively, and the 1/10-diluted wastewater was used for the study. The treatment characteristics were compared between the conventionally generated ozone (105 ) and microbubbled ozone (13 ). The use of microbubbled ozone improved the removal of chemical oxygen demand (COD) and color by 85% and 26%, respectively, compared with the conventionally bubbled ozone. The application of microbubbled , , combinations resulted in 5~10% higher color removal than ozone alone, which implies that the contribution of UV or is not significant in color removal. On the other hand, COD removal could be increased two folds compared with ozone alone through combination. The contribution of was bigger than UV for COD removal with microbubbled ozone. Due to the enhancement of dissolved ozone and radical activity, the microbubbling enabled us to additional COD removal even after stopping ozone supply in the presence of UV or .