[Study on the denitrification of drinking water with upflow anaerobic sludge blanket reactor]

The characteristics of denitrification was investigated with a pilot scale upflow anaerobic sludge blanket (UASB) reactor at room temperature. The results showed that when brewery waste degrading sludge was used as seed, the starting process was completed within 7 weeks, with hydraulic residence time shortened from 11.1 h to 4.7 h, COD/N/P = 200/5/1 and influent NO3-(-)N concentration increased from 5 mg/L to 100 mg/L. After the process starting, the most probable number [n(MPN)] of denitrifying bacteria was 60 folds and the maximum velocity of CH4 produced was 10 folds higher than before. The removal efficiency of No3-(-)N was 99%, C/N ratio and pH value were investigated as effect factors. When C/N > = or 1.0, the NO3(-)-N removal efficiencies were not different from those of C/N < 1.0 groups significantly. The pH value could meet the discharge standards.