Effect of pH Value on Denitrification Phosphorus Removal in Sequencing Batch Reactor

This paper is aimed to solve the effect of pH value in denitrification and phosphorus removal process, and to determine the best pH value for the treatment. pH value was an important indicator of activated sludge reaction in the water treatment process, and it was necessary to keep the suitable pH value to obtain a good treatment effect. The influence of anaerobic phosphorus release and anoxic phosphorus absorption under pH = 6.0, pH = 7.0 and pH = 8.0 in sequencing batch reactor was studied in this paper. The experiment results showed that, in anaerobic phase, anaerobic phosphorus release increased with the increase of pH value, and no significant change was observed in HRT for anaerobic. In anoxia phase, when pH = 6.0, the activity of denitrifying phosphorus removal bacteria was significantly inhibited and phosphorus absorption was poor. When pH = 7.0 and 8.0, the anoxic phosphorus uptake and denitrification system worked well. In the late stages of anoxic phase pH>8.0, the release and absorption of phosphorus was also very stable.