Treatment of Landfill Leachate Using Palm Oil Mill Effluent
Abstract
:1. Introduction
2. Methodology
2.1. Collection of the Samples and Landfill Characteristics
2.2. Leachate and POME Characterizations
2.3. Experimental Procedure
2.4. Effect of the Leachate/POME Ratio
2.5. Optimization of Treatment Efficiencies of Targeted Parameters
Analytical Work
3. Results and Discussion
3.1. Effects of Aeration Time Variation on the Removal Efficiency during the Aeration Process of Leachate Treatment
3.2. Effects of Reaction Time Variation on the Removal Efficiency during the Aeration Time of Leachate/POME Treatment (Ratio 900 mL Leachate/100 mL POME)
3.3. Effects of Reaction Time Variation on the Removal Efficiency during the Aeration Time of Leachate/POME Treatment (Ratio 700 mL Leachate/300 mL POME)
3.4. Effects of Reaction Time Variation on the Removal Efficiency during the Aeration Time of Leachate/POME Treatment (Ratio 500 mL Leachate/500 mL POME)
3.5. Effects of the Leachate/POME Mixing Ratio on the Leachate Aeration Process
3.6. Analysis of Variance
3.7. Optimization of Leachate Treatment Using POME
3.8. Heavy Metal Analysis
4. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Parameter | Mean and Standard Deviation | (USEPA *; DOE **) |
---|---|---|
pH | 7.88 ± 0.50 | 6–9 ** |
EC (µS/cm) | 6565 ± 324 | 1400 * |
TDS (mg/L) | 4671 ± 174 | 1000 * |
TSS (mg/L) | 40.45 ± 8 | 50 ** |
COD (mg/L) | 893.41 ± 202 | 400 ** |
BOD5 (mg/L) | 59.20 ± 10 | 20 ** |
NH3-N (mg/L) | 530.7 ± 22 | 5 ** |
DO (mg/L) | 5.43 ± 2 | 5 * |
Mg2+ (mg/L) | 19.72 ± 4 | 0.2 * |
Ca2+ (mg/L) | 39.72 ± 34 | 0.1 * |
Na+ (mg/L) | 638.80 ± 303 | 0.02 ** |
Fe2+ (mg/L) | 0.78 ± 0.6 | 5 ** |
Zn2+ (µg/L) | 280 ± 16 | 2 ** |
Cu2+ (µg/L) | 41.87 ± 24 | 0.2 ** |
Cr2+ (µg/L) | 45.11 ± 17 | 0.01 ** |
Cd2+ (µg/L) | 0.62 ± 0.7 | 0.01 ** |
Pb+ (µg/L) | 4.18 ± 2.7 | 0.01 ** |
As3+ (µg/L) | 17.3 ± 7 | 0.05 ** |
Co2+ (µg/L) | 11.05 ± 8 | 0.05 * |
Mn2+ (µg/L) | 61.40 ± 49 | 0.02 ** |
Parameter | Mean and Standard Deviation | (Standard of DOE *) |
---|---|---|
pH | 4.40 ± 0.01 | 5.0–9.0 |
EC (µS/cm) | 8553 ± 114 | 100 |
Salinity (ppt) | 4.9 ± 0 | NA |
TDS (mg/L) | 5713 ± 15 | NA |
TSS (mg/L) | 3483 ± 76 | 200 |
Color (Pt/Co) | 5517 ± 104 | 100 |
COD (mg/L) | 17,400 ± 100 | NA |
BOD5 (mg/L) | 1243 ± 51 | NA |
BOD5/COD | 0.07 ± 0 | NA |
NH3-N (mg/L) | 308 ± 58 | NA |
DO (mg/L) | 6.74 ± 0.05 | NA |
Mg2+ (mg/L) | 285 ± 5 | NA |
Ca2+ (mg/L) | 47.34 ± 0.03 | NA |
Fe2+ (mg/L) | 45.31 ± 0.9 | 50 |
Zn2+ (µg/L) | 2603 ± 5.77 | 10 |
Cu2+ (µg/L) | 2130.00 ± 26.46 | 10 |
Cr2+ (µg/L) | 910.00 ± 10 | NA |
Cd2+ (µg/L) | 90.10 ± 0.03 | NA |
Pb+ (µg/L) | 54.38 ± 0.31 | NA |
As3+ (µg/L) | 100.22 ± 0.44 | NA |
Co2+ (µg/L) | 41.08 ± 0.17 | NA |
Mn2+ (µg/L) | 80.15 ± 0.26 | 10 |
Run | Factor A: POME (mL) | Factor B: Aeration Time (day) | COD Removal % | Color Removal % | TSS Removal % | NH3-N Removal % | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Actual | Predicted | Residual | Actual | Predicted | Residual | Actual | Predicted | Residual | Actual | Predicted | Residual | |||
1 | 150 | 21 | 84.5 | 84.79 | −0.29 | 51.89 | 55.1 | −3.21 | 79 | 65.53 | 13.47 | 94 | 94.26 | −0.26 |
2 | 150 | 14 | 78.81 | 80.18 | −1.37 | 47.58 | 46.1 | 1.48 | 53.2 | 53.57 | −0.37 | 93 | 92.83 | 0.17 |
3 | 150 | 14 | 78.31 | 80.18 | −1.87 | 44.73 | 46.1 | −1.37 | 51.3 | 53.57 | −2.27 | 93 | 92.83 | 0.17 |
4 | 150 | 7 | 65.8 | 67.58 | −1.78 | 24.21 | 21.37 | 2.84 | 25.6 | 36.92 | −11.32 | 81 | 80.6 | 0.4 |
5 | 150 | 14 | 78.18 | 80.18 | −2 | 47.69 | 46.1 | 1.59 | 54 | 53.57 | 0.43 | 93 | 92.83 | 0.17 |
6 | 300 | 14 | 84.9 | 86.02 | −1.12 | 32.9 | 30.98 | 1.92 | 44 | 47.46 | −3.46 | 90 | 88.93 | 1.07 |
7 | 0 | 14 | 33.46 | 34.4 | −0.94 | 23.44 | 25.73 | -2.29 | 36 | 30.38 | 5.62 | 94 | 94.93 | −0.93 |
8 | 0 | 7 | 21.66 | 20.82 | 0.84 | 2.92 | 3.29 | -0.37 | 18.46 | 15.07 | 3.39 | 85 | 84.7 | 0.3 |
9 | 300 | 7 | 75.32 | 74.39 | 0.93 | 1.5 | 3.97 | −2.47 | 37.4 | 29.47 | 7.93 | 74 | 74.7 | −0.7 |
10 | 0 | 21 | 40.08 | 39.98 | 0.099 | 35.1 | 32.44 | 2.66 | 32 | 41 | −9 | 95 | 94.37 | 0.63 |
11 | 300 | 21 | 89.83 | 89.64 | 0.19 | 42.81 | 42.26 | 0.55 | 56.3 | 60.76 | −4.46 | 92 | 92.37 | −0.37 |
12 | 150 | 14 | 84.46 | 80.18 | 4.28 | 44.71 | 46.1 | −1.39 | 54.4 | 53.57 | 0.83 | 93 | 92.83 | 0.17 |
13 | 150 | 14 | 83.22 | 80.18 | 3.04 | 46.15 | 46.1 | 0.052 | 52.8 | 53.57 | −0.77 | 92 | 92.83 | −0.83 |
COD Removal (%) | Source | Sum of Squares | DF | Mean Square | F Value | Prob > F |
Model | 5981.97 | 5 | 1196.39 | 190.7 | <0.0001 | |
A | 3996.42 | 1 | 3996.42 | 637 | <0.0001 | |
B | 444.28 | 1 | 444.28 | 70.81 | <0.0001 | |
A2 | 1101.81 | 1 | 1101.81 | 175.62 | <0.0001 | |
B2 | 44.26 | 1 | 44.26 | 7.06 | 0.0326 | |
AB | 3.82 | 1 | 3.82 | 0.61 | 0.4607 | |
Residual | 43.92 | 7 | 6.27 | |||
Lack of Fit | 7.85 | 3 | 2.62 | 0.29 | 0.8314 | |
Pure Error | 36.07 | 4 | 9.02 | |||
Cor Total | 6025.89 | 12 | ||||
SD: 2.50, R2: 0.9927, mean: 69.12, CV:3.62, Pred R2: 0.9814, Adeq Precision: 40.447. | ||||||
TSS Removal (%) | Source | Sum of Squares | DF | Mean Square | F Value | Prob > F |
Model | 2468.26 | 5 | 493.65 | 6.46 | 0.0148 | |
A | 437.59 | 1 | 437.59 | 5.72 | 0.048 | |
B | 1228.08 | 1 | 1228.08 | 16.06 | 0.0051 | |
A2 | 592.46 | 1 | 592.46 | 7.75 | 0.0272 | |
B2 | 15.2 | 1 | 15.2 | 0.2 | 0.6691 | |
AB | 7.18 | 1 | 7.18 | 0.094 | 0.7681 | |
Residual | 535.16 | 7 | 76.45 | |||
Lack of Fit | 529.33 | 3 | 176.44 | 121.02 | 0.0002 | |
Pure Error | 5.83 | 4 | 1.46 | |||
Cor Total | 3003.43 | 12 | ||||
SD: 8.74, R2: 0.8218, mean: 45.73, CV:19.12, Pred R2: −0.7897, Adeq Precision: 8.495. | ||||||
Color Removal (%) | Source | Sum of Squares | DF | Mean Square | F Value | Prob > F |
Model | 3328.56 | 5 | 665.71 | 94.36 | <0.0001 | |
A | 41.34 | 1 | 41.34 | 5.86 | 0.046 | |
B | 1705.89 | 1 | 1705.89 | 241.8 | <0.0001 | |
A2 | 869.58 | 1 | 869.58 | 123.26 | <0.0001 | |
B2 | 170.8 | 1 | 170.8 | 24.21 | 0.0017 | |
AB | 20.84 | 1 | 20.84 | 2.95 | 0.1294 | |
Residual | 49.39 | 7 | 7.06 | |||
Lack of Fit | 40.88 | 3 | 13.63 | 6.41 | 0.0523 | |
Pure Error | 8.5 | 4 | 2.13 | |||
Cor Total | 3377.94 | 12 | ||||
SD: 2.66, R2: 0.9854, mean: 34.28, CV: 7.75, Pred R2: 0.8733, Adeq Precision: 28.712. | ||||||
NH3-N Removal (%) | Source | Sum of Squares | DF | Mean Square | F Value | Prob > F |
Model | 458.76 | 5 | 91.75 | 154.36 | <0.0001 | |
A | 54 | 1 | 54 | 90.85 | <0.0001 | |
B | 280.17 | 1 | 280.17 | 471.33 | <0.0001 | |
A2 | 2.22 | 1 | 2.22 | 3.73 | 0.0446 | |
B2 | 80.43 | 1 | 80.43 | 135.32 | <0.0001 | |
AB | 16 | 1 | 16 | 26.92 | 0.0013 | |
Residual | 4.16 | 7 | 0.59 | |||
Lack of Fit | 3.36 | 3 | 1.12 | 5.6 | 0.0647 | |
Pure Error | 0.8 | 4 | 0.2 | |||
Cor Total | 462.92 | 12 | ||||
SD: 0.77, R2: 0.991, mean: 89.92, CV: 0.86, Pred R2: 0.9238, Adeq Precision: 38.623. |
POME | Aeration Time | COD Removal (%) | TSS Removal (%) | Color Removal (%) | NH3-N Removal (%) | Desirability |
---|---|---|---|---|---|---|
188.38 | 21.00 | 89.83 | 67.10 | 55.19 | 93.95 | 0.935 |
Lab experiment | 87.15 | 65.54 | 52.78 | 91.75 |
Heavy Metals | Initial Concentration in Leachate | Residual after Treatment Process | Removal (%) |
---|---|---|---|
Fe2+ (µg/L) | 20.04 ± 7.11 | 1856 ± 0.57 | 90.73 |
Zn2+ (µg/L) | 280.00 ± 19.63 | 10.76 ± 2.10 | 96.16 |
Cu2+ (µg/L) | 41.91 ± 20.19 | 1.28 ± 0.64 | 96.95 |
Cr2+ (µg/L) | 45.11 ± 12.81 | 2.80 ± 1.01 | 93.78 |
Cd2+ (µg/L) | 22.62 ± 3.51 | 0.23 ± 0.20 | 99.00 |
Pb+ (µg/L) | 4.18 ± 2.91 | 0.28 ± 0.12 | 93.30 |
As3+ (µg/L) | 17.34 ± 4.29 | 16.15 ± 2.37 | 6.85 |
Co2+ (µg/L) | 11.05 ± 5.54 | 0.53 ± 0.39 | 95.24 |
Mn2+ (µg/L) | 48.61 ± 14.99 | 31.72 ± 7.16 | 34.75 |
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Banch, T.J.H.; Hanafiah, M.M.; Amr, S.S.A.; Alkarkhi, A.F.M.; Hasan, M. Treatment of Landfill Leachate Using Palm Oil Mill Effluent. Processes 2020, 8, 601. https://doi.org/10.3390/pr8050601
Banch TJH, Hanafiah MM, Amr SSA, Alkarkhi AFM, Hasan M. Treatment of Landfill Leachate Using Palm Oil Mill Effluent. Processes. 2020; 8(5):601. https://doi.org/10.3390/pr8050601
Chicago/Turabian StyleBanch, Tawfiq J. H., Marlia M. Hanafiah, Salem S. Abu Amr, Abbas F. M. Alkarkhi, and Mohammed Hasan. 2020. "Treatment of Landfill Leachate Using Palm Oil Mill Effluent" Processes 8, no. 5: 601. https://doi.org/10.3390/pr8050601