1.The DO is about 4 ppm, the O2 should not the matter. 2.The TKN of inflow is 30~40 ppm, the TKN of effluent is 4 ppm, the NH3-N is nitrification in the last month.

1.The DO is about 4 ppm, the O2 should not the matter.

2.The TKN of inflow is 30~40 ppm, the TKN of effluent is 4 ppm, the NH3-N is nitrification in the last month.

1.The DO is ​about 4 ​ppm, the O2 should not the matter. 2.The TKN of ​inflow is 30~40 ​ppm, the TKN of ​effluent is 4 ​ppm, the NH3-N ​is nitrification in ​the last ​month.