抄録
The nitrification and removals of NH3-N, NO2-N and NO3-N by activated sludge were examined.
1) When NH3-N was added, NO3-N accumulated with correspondence to the decrease of NH3-N. When glucose or sodium acetate was added simultaneously, NH3-N and Inorganic-N (total amounts of NH3-N, NO2-N and NO3-N) decreased rapidly. When xylose was added simultaneously, the decrease rate of these substances was not larger than those with glucose or acetate.
In alkaline range, NH3-N decreased and NO2-N accumulated. NO3-N accumulated in neutral and alkaline range. Inorganic-N was removed around neutrality.
2) When NO2-N was added, NO2-N changed to NO3-N, and the effect of carbon sources was small. In acidic range, NO2-N decreased and NH3-N increased. NO3-N accumulated in neutral and alkaline range.
3) When NO3-N was added, this substance decreased slowly. When glucose and sodium acetate was added simultaneously, the decrease rate of NO3-N became larger, but the effect of xylose was not large. NO3-N decreased rapidly in acidic range. NH3-N increased in acidic range and NO2-N did in acidic and alkaline ranges, especially in alkaline range accumulation of NO2-N was large.
