Removal of COD from a stabilized landfill leachate by physicochemical and advanced oxidative process

Abstract

This work investigated the effectiveness of a physicochemical and oxidative process for the removal of chemical oxygen demand (COD) from stabilized landfill leachates. The application of these technologies for landfill leachate treatment greatly depends on the optimal operating conditions for a specific leachate. Coagulation-flocculation followed by H2O2, Fenton and photo-Fenton processes was evaluated. Advanced oxidation processes were evaluated in the raw leachate and the leachate pretreated by coagulation-flocculation. Via the coagulation process, at 30 sec and a stirring speed of 150 rpm followed by flocculation and settling steps, 53% COD was removed at an optimal dose of 1400 mg L(-1) and pH 4.0. Moreover, from the POA evaluated, the Fenton process was determined to be the most effective process for removing COD from the leachate pretreated by coagulation-flocculation, reaching 83.3% COD removal with 1330 mg L(-1) of H2O2 and 266 mg L(-1) of Fe(2+). The photo-Fenton process applied directly to the raw effluent was effective for the removal of COD; a 75% reduction in COD was observed in tests using 2720 mg L(-1) of H2O2 and 544 mg L(-1) of Fe(2+). Due to the variability in the composition of the Gramacho landfill leachate, the combination of coagulation-flocculation and the Fenton process is an effective technology for reducing the COD in samples of this leachate.

Using advanced statistical tools to assess the impact of a small landfill site on the aquatic environment

“…Accordingly, Cheibub et al ( 2014 ) considered meeting an acceptable COD to be generally possible with the combined processes of coagulation/flocculation and the Fenton process of leachate treatment from landfills. The concentration of total N was 87.19 mg/L and N–NO 3 was 134.50 mg/L, also high values.…”

An Extensive Analysis of Combined Processes for Landfill Leachate Treatment

“…In studies conducted by Moradi and Ghanbari [64], Cheibub [108], and Amor [58], they focused on the removal of COD from LL using the combined C/F and Fenton or photo-Fenton treatment processes. Moradi and Ghanbari [64] employed the combined C/F and Fenton processes for young LL treatment.…”

“…Similarly, Cheibub [108] studied the removal of COD from stabilized LL using the combined C/F followed by Fenton and photo-Fenton (PF) treatment processes. Treatment with FeCl 3 in the C/F removed approximately 53% of COD.…”

Remoção da cor no tratamento combinado de lixiviado de aterro sanitário e esgoto doméstico via processo PACT®

“…A cor em lixiviados de aterros sanitários está relacionada à concentração de substâncias húmicas presentes, que conferem recalcitrância a esse efluente (CHEIBUB; CAMPOS; FONSECA, 2014). Mesmo não havendo, na legislação ambiental, exigências quanto a essas substâncias, seu acompanhamento se mostra relevante e pode ser realizado indiretamente por meio da avaliação da cor.…”