Case study Nordre Follo Wastewater Treatment Plant, Norway
Municipal treatment plant for nitrogen removal. The plant was upgraded from an existing chemical treatment plant.
Design data
| Parameter |
Value |
| Total BOD7 |
2 660 kg/d |
| Total COD |
5 900 kg/d |
| TN |
460 kg/d |
| SS |
4 390 kg/d |
| NH4-N |
320 kg/d |
| Design flow |
750 m³/h |
| Maximum flow |
1 125 m³/h |
| PE |
40 000 |
| Temperature range |
10°C |
Effluent requirements
| Parameter |
Annual average |
| Phosphorous |
<0.3 mg /l, 90% reduction, 0.6 mg/l (maximum) |
| Nitrogen |
70% reduction of TN |
| BOD7 |
90% reduction |
Results
| Parameter |
Influent (mg/l) |
Effluent(mg/l) |
Reduction (%) |
| Total COD |
400.8 |
54.2 |
86.5 |
| Total BOD7 |
131 |
5.5 |
95.8 |
| TN |
31.7 |
8.8 |
72.4 |
| TP |
4.2 |
0.17 |
96 |
A guarantee period of four months was arranged to prove that the plant could meet the effluent requirements. The results are given in the table.