Table 3.
COD, Color and Turbidity results for each stage of the proposed landfill leachate treatment system, the coagulation/flocculation (CF), hydrodynamic cavitation (HC) plus ozonation (O3) and activated carbon (AC) application.
| Parameters | PGα21Ca–pH 4 | AlCl3–pH 5 | FeCl3–pH 5 | Al2(SO4)3–pH 5 | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| AV | SD | EF (%) | AV | SD | EF (%) | AV | SD | EF (%) | AV | SD | EF (%) | |
| COD (mg L−1) | ||||||||||||
| LL | 2425 | 2425 | 2425 | 2209 | ||||||||
| CF | 1466 | 118 | 39.5 | 1595 | 266 | 34.2 | 1731 | 253 | 28.6 | 1444 | 486 | 34.6 |
| HC + O3 1H | 702 | 86.8 | 31.5 | 722 | 84.0 | 36.0 | 770 | 179 | 39.6 | 798 | 181 | 29.2 |
| HC + O3 2H | 662 | 72.0 | 1.6 | 582 | 81.3 | 5.8 | 642 | 175 | 5.3 | 543 | 191 | 11.5 |
| AC | 183 | 10.1 | 19.8 | 347 | 18.3 | 9.7 | 444 | 68.4 | 8.2 | 369 | 22.5 | 7.9 |
| Total | 92.5B | 85.7A | 81.7A | 83.3A | ||||||||
| Color (mg Pt–Co L−1) | ||||||||||||
| LL | 3760 | 3840 | 3840 | 4080 | ||||||||
| CF | 1462 | 171 | 59.1 | 1537 | 484 | 60.0 | 2857 | 25 | 25.6 | 2903 | 535 | 28.8 |
| HC + O3 1H | 425 | 70.9 | 33.2 | 203 | 50.3 | 34.7 | 1053 | 491 | 47.0 | 637 | 211 | 55.6 |
| HC + O3 2H | 202 | 30.6 | 3.3 | 143 | 15.3 | 1.6 | 710 | 451 | 8.9 | 347 | 86.2 | 7.1 |
| AC | 170 | 21.2 | 2.1 | 102 | 24.3 | 1.1 | 383 | 145 | 8.5 | 103 | 70.9 | 6.0 |
| Total | 97.7B | 97.3B | 90.0A | 97.5B | ||||||||
| Turbidity (NTU) | ||||||||||||
| LL | 11.2 | 11.2 | 11.2 | 10.4 | ||||||||
| CF | 20.0 | 1.9 | − 78.3 | 10.6 | 2.0 | 5.8 | 14.0 | 3.7 | − 25.0 | 20.3 | 3.1 | − 95.5 |
| HC + O3 1H | 1.7 | 0.3 | 162.8 | 1.6 | 0.4 | 79.7 | 9.4 | 1.2 | 41.5 | 13.0 | 4.7 | 70.6 |
| HC + O3 2H | 1.3 | 0.04 | 4.0 | 1.4 | 0.4 | 2.1 | 11.4 | 2.2 | − 18.4 | 5.7 | 0.2 | 70.2 |
| AC | 3.9 | 1.2 | − 22.9 | 4.1 | 1.6 | − 24.3 | 15.1 | 3.0 | − 32.6 | 2.5 | 1.7 | 30.3 |
| Total | 65.6B | 63.2B | − 34.5A | 75.6B | ||||||||
Treatments with the same letter have no significant difference according to the Tukey test (p < 0.05, n = 12). LL, Landfill leachate; CF, Coagulation/flocculation; HC + O3 1H, Hydrodynamic cavitation plus Ozonation after one hour test; HC + O3 2H, Hydrodynamic cavitation plus Ozonation after two hours test; AV, Average; SD, Standard deviation; EF, Efficiency; COD, Chemical oxygen demand.