Advanced Nitrogen Treatment - Microbial Immobilization Technology
Hitachi combined “anammox” and “Bacteria entrapment”.
→More effective biological treatment system
anammox bacteria easily wash out from the reactor due to the slow growth rate. (one- tenth that of nitrifier)
Microorganism entrapment by PEG
Hitachi has already used the gel entrapment technique in many installation.
| Facility | NH4-N conc. | PEGASUS (Conventional nitrification) |
anammox process | |
|---|---|---|---|---|
| ① | Biological tank | Low(30-50) | ✔ | |
| ② | Post nitrogen treatment | Low(15-30) | ✔ | ✔ (On-going R&D) |
| ③ | For side stream nitrogen treatment | High(500-1000) | ✔ (Multi-stage nitrification) |
✔ |
| Conventional process (Nitrification- Denitrification) |
anammox process | |
|---|---|---|
| Reactor principle |  |
 |
| Reactor volume | Large | Small |
| O2 supply | Large | Small |
| Chemical dosing (for denitrification) |
Need | No Need |
| Sludge production | Large | Small |
| Optimum temp. | Normal (10-37℃) | High (25-37℃) |
The anammox process is a cost-effective means of biological ammonia removal. (anammox : anaerobic ammonium oxidation)
