Table 1.
PPWW physicochemical characteristics in comparison with Tunisian standards (INNORPI “ground water discharge of waste water” 1989) and with American Public Health Association (APHA 2005) standards for wastewater discharge
| Characteristics | PPWW (SD) | INNORPI (SD) | APHA (SD) |
|---|---|---|---|
| pH (25 °C) | 7.42 (0.2) | 8.5(0.2) | 9 (0.2) |
| EC (mS cm−1) (25 °C) | 9.35 (0.2) | 7.00(0.2) | 6 (0.2) |
| Turbidity (NTU) | 605 (3) | 70.00(2) | NI |
| COD (mg O2 l−1) | 63.23 (3) | 90.00(2) | 70(2) |
| BOD5 (mg O2 l−1) | 14.55 (0.5) | 30.00(1) | ≤ 30(1) |
| COD/BOD5 | 4.34 ± (0.1) | 3.00(0.1) | NI |
| Suspended matter (g l−1) | 19.16 (0.5) | 0.03(0.01) | ≤ 0.03(0.01) |
| Dry matter (g l−1) | 29.46 (0.5) | NI | NI |
| Organic matter (g l−1) | 4.46 (0.1) | NI | NI |
| Mineral matter (g l−1) | 24.82 (0.5) | NI | NI |
| Total nitrogen (mg l−1) | 43.42 (1) | 90.00(2) | ≤50(2) |
| Ammoniacal nitrogen (mg l−1) | 31.73 (1) | NI | NI |
| Organic nitrogen (mg l−1) | 11.66 (0.5) | NI | NI |
| P (mg l−1) | 55.40 (2) | 10.00(1) | ≤10(1) |
| K (g l−1) | 1.26 (0.02) | 0.05 (0.01) | 0.3 (0.01) |
| Ca (g l−1) | 1.06 (0.02) | 0.50 (0.01) | 0.2 (0.01) |
| Na (g l−1) | 0.85 (0.02) | 0.50 (0.01) | 0.2 (0.01) |
| Cu (mg l−1) | 0.83 (0.02) | 0.50 (0.01) | ≤0.25 (0.01) |
| Zn (mg l−1) | 0.94 (0.02) | 5.00 (0.2) | ≤1.00 (0.1) |
| Fe (mg l−1) | 370.32 (3) | 5.00 (0.2) | ≤5 (0.2) |
| Cd (mg l−1) | 1.21 (0.02) | 0.1 (0.01) | ≤0.1 (0.01) |
| Pb (mg l−1) | 1.05 (0.02) | 1.00 (0.01) | ≤0.10 (0.01) |
PPWW averaged values of three repetitions for each analysis, SD standard deviation (P ≤ 0.05), NI not identified