| Abstract | The aim of this study was to check the effectiveness of the Fenton's reagent (Fe2+ + H2O2 + H+) for the pre-treatment of a municipal landfill leachate with the objective of improving its overall biodegradability, evaluated in terms of BOD5/COD ratio, up to a value compatible with biological treatment. The leachate came from a municipal sanitary landfill located in southern Italy and the average values of its main parameters were: pH = 8.2; COD = 10 540 mg l(-1); BOD5=2300 mg l(-1); TOC=3900 mg l(-1); NH4-N=5210 mg l(-1); conductivity = 45350 muS cm(-1); alkalinity= 21470 mg l(-1) CaCO3. The effect of initial pH value on the pre-treatment effectiveness was evaluated by titrating the amount of acidic by-products formed. The extent of leachate oxidation was monitored and controlled by both pH and redox potential measurements. The best operational conditions for achieving the desired goal (i.e., BOD5/COD greater than or equal to 0.5) resulted: Fe2+ = 275 mg l(-1); H2O2 = 3300 mg l(-1); initial pH = 3; reaction time = 2 h. At the end of the Fenton's pretreatment, in order to permit a subsequent biological treatment, residual ferric ions were removed increasing the pH up to 8.5 by adding 3 g l(-1) of Ca(OH)(2) and 3 mg l(-1) of a cationic polyelectrolyte, the latter as an aid to coagulation. This final step also resulted in a further modest removal of residual COD due to co-precipitation phenomena. |
| Text | 42217 2004 10.1016/j.chemosphere.2003.09.015 ISI Web of Science WOS 000187802800024 Fenton s pre treatment of mature landfill leachate LOPEZ A., PAGANO M., VOLPE A., DI PINTO A.C. PAGNO MICHELE Consiglio Nazionale delle Ricerche, Istituto di Ricerca Sulle Acque, Reparto di Chimica e Tecnologia delle Acque, Via Francesco De Blasio, 5, 70123 Bari, Italy LOPEZ ANTONIO Consiglio Nazionale delle Ricerche, Istituto di Ricerca Sulle Acque, Reparto di Chimica e Tecnologia delle Acque, Via Francesco De Blasio, 5, 70123 Bari, Italy VOLPE ANGELA Consiglio Nazionale delle Ricerche, Istituto di Ricerca Sulle Acque, Reparto di Chimica e Tecnologia delle Acque, Via Francesco De Blasio, 5, 70123 Bari, Italy DI PINTO APPIO CLAUDIO Consiglio Nazionale delle Ricerche, Istituto di Ricerca Sulle Acque, Reparto di Chimica e Tecnologia delle Acque, Via Reno, 1, 00198 Roma, Italy The aim of this study was to check the effectiveness of the Fenton s reagent Fe2 H2O2 H for the pre treatment of a municipal landfill leachate with the objective of improving its overall biodegradability, evaluated in terms of BOD5/COD ratio, up to a value compatible with biological treatment. The leachate came from a municipal sanitary landfill located in southern Italy and the average values of its main parameters were pH = 8.2; COD = 10 540 mg l 1 ; BOD5=2300 mg l 1 ; TOC=3900 mg l 1 ; NH4 N=5210 mg l 1 ; conductivity = 45350 muS cm 1 ; alkalinity= 21470 mg l 1 CaCO3. The effect of initial pH value on the pre treatment effectiveness was evaluated by titrating the amount of acidic by products formed. The extent of leachate oxidation was monitored and controlled by both pH and redox potential measurements. The best operational conditions for achieving the desired goal i.e., BOD5/COD greater than or equal to 0.5 resulted Fe2 = 275 mg l 1 ; H2O2 = 3300 mg l 1 ; initial pH = 3; reaction time = 2 h. At the end of the Fenton s pretreatment, in order to permit a subsequent biological treatment, residual ferric ions were removed increasing the pH up to 8.5 by adding 3 g l 1 of Ca OH 2 and 3 mg l 1 of a cationic polyelectrolyte, the latter as an aid to coagulation. This final step also resulted in a further modest removal of residual COD due to co precipitation phenomena. 54 http //biblioproxy.cnr.it 2063/science/article/pii/S0045653503009287 articolo fenton.pdf Articolo in rivista Elsevier 0045 6535 Chemosphere Chemosphere Chemosphere Chemosphere. Chemosphere. Environmental chemistry, Chemosphere. Persistent organic pollutants and dioxins, Chemosphere. Environmental toxicology and risk assessment, Chemosphere. Science for Environmental toxicology, appioclaudio.dipinto DI PINTO APPIO CLAUDIO angela.volpe VOLPE ANGELA antonio.lopez LOPEZ ANTONIO michele.pagano PAGANO MICHELE |
