Table 2 Physicochemical variables based on spatial and temporal sampling
No. | Variable | Time | Raw sewage | Aeration basin | Effluent water | Upstream | Downstream |
|---|---|---|---|---|---|---|---|
1 | TSS (mg/l) | April | 110 | 15 | 20 | 10 | 20 |
July | 140 | 100 | 25 | 100 | 30 | ||
2 | Temp. (°C) | April | 18 | 17 | 18 | 17 | 18 |
July | 23 | 22 | 23 | 22 | 23 | ||
3 | Alkal. (ppm) | April | 390 | 300 | 310 | ||
July | 380 | 370 | 350 | ||||
4 | pH | April | 7.9 | 7.7 | 7.6 | ||
July | 7.8 | 7.5 | 7.5 | ||||
5 | NO3 (mg/l) | April | 10 | 8 | 10 | 6 | 8 |
July | 200 | 200 | 20 | 200 | 25 | ||
6 | P (mg/l) | April | 3.8 | 0.3 | 2.3 | 0.4 | 0.5 |
July | 3.9 | 2.8 | 2.4 | 0.3 | 2.6 | ||
7 | BOD (mg/l) | April | 125 | 25 | 15 | 5 | 20 |
July | 200 | 100 | 15 | 10 | 80 | ||
8 | COD (mg/l) | April | 390 | 300 | 40 | ||
July | 400 | 310 | 80 | ||||
9 | DO (mg/l) | April | 4 | 8 | 4 | 3 | 6 |
July | 10 | 10 | 5 | 5 | 10 |