Abstract
Reject water from advanced sludge dewatering process was characterized by high concentrations of ammonia nitrogen, high pH and high alkalinity. The effects of air-liquid ratio, temperature and stripping time on the removal of ammonia nitrogen from the reject water were investigated, and the phenomena of pH decrease and scaling during the stripping process were analyzed. High pH and high alkalinity of the reject water were conducive to the progress of stripping, while the increase of air-liquid ratio and temperature could both improve the stripping efficiency. Ammonia air stripping also results in the simultaneous decrease of pH and Ca2+ concentration. The decrease of pH was in favor of subsequent biological treatment of the reject water, while the latter decrease caused the precipitation of CaCO3 in the stripping equipment.
| Original language | English |
|---|---|
| Pages (from-to) | 1093-1097 |
| Number of pages | 5 |
| Journal | Chinese Journal of Environmental Engineering |
| Volume | 9 |
| Issue number | 3 |
| State | Published - 5 Mar 2015 |
| Externally published | Yes |
Keywords
- Advanced sludge dewatering
- Ammonia nitrogen
- Reject water
- Scaling
- Stripping