[Study on treatment of simulant dairy processing wastewater using FCR multilevel contact oxidation system]

This study applied new helical-fibrous fillers as carrier to treat simulant dairy industrial wastewater in order to improve the ability of nitrogen removal and decontamination. Based on multilevel oxidation system where the food chain was formed by different kinds of microbe, removal ratio and removal mechanism of COD, TN, NH4+ -N, TP under different HRT and effect of sludge reduction were discussed. When COD of influent was 842-1843 mg/L, TN concentration was 36.3-92.2 mg/L, NH4+ -N concentration was 30.1-52.1 mg/L, and HRT was 6h, the removal ratio of COD, TN and NH4+ -N was 93.3%, 73.3% and 80.7% respectively. COD, TN and NH: -N for effluent was 79.4 mg/L, 9.6 mg/L and 6.1 mg/L, both bellow the first degree of Integrated Wastewater Discharge Standard (GB 8978-2002). This system not only could remove nitrogen effectively, but also discharged little excessive sludge, and the average sludge production was 7.7%. It shows that this system could be conveniently operated and be used in the long term with low cost, and could be used in treating municipal wastewater and high concentration organic wastewater such as restaurant wastewater and food industry wastewater.