Leachate treatment process at a municipal stabilized landfill by catalytic ozonation: an exploratory study from Taguchi orthogonal array

Abstract

-Catalytic ozonation has been recognized in the scientific community as an efficient technique, reaching elevated rates of recalcitrant organic material mineralization, even at the presence of scavenger species of hydroxyl free radicals. This study presents the most significant factors involving the leachate treatment stabilized by the municipal landfill of the city of Guaratinguetá, State of São Paulo, Brazil, by using a catalytic ozonation activated by metallic ions Fe 3+ , Zn 2+ , Mn 2+ , Ni 2+ and Cr 3+ . The Taguchi L 16 orthogonal array and its associated statistical methods were also used in this study. Among the researched ions, the most notable catalysis was obtained with ferric ion, statistically significant in the reduction of COD with a confidence level of 99.5%.

[RETRACTED ARTICLE]Use of a sonocatalytic process to improve the biodegradability of landfill leachate

“…In general, biological processes are preferred for the treatment of leachates with a high ratio of biochemical oxygen demand to chemical oxygen demand (BOD U /COD) (Peixoto et al, 2009) and of fresh leachates containing mainly volatile fatty acids (Abdul Aziz et al, 2011). Compact physical and chemical methods have been suggested for the treatment of old, stabilized and dilute leachates with low biodegradability (Kurniawan et al, 2004;Kargi et al, 2004).…”

Statistical evaluation of mature landfill leachate treatment by homogeneous catalytic ozonation

“…Analytical determinations of COD of the treated leachate samples were carried out immediately after the conclusion of each experiment of catalytic ozonation. There was no sample filtration prior to the respective leachate digestion in the closed Hach tube (Peixoto et al, 2008;Peixoto et al, 2009). …”

“…The leachate was treated as collected in the municipal landfill, with no further pretreatment, such as filtration. The following experimental conditions were used, according to a previous study (Peixoto et al, 2009) , and pH equal to 5.0. Moreover, the temporal control of leachate degradation (% COD removal) was performed in some of the experiments of Taguchi's L 8 design in order to confirm the results obtained in the preliminary experiment.…”

“…Ozone feeding into the wastewater was performed continuously at the reactor bottom (Peixoto et al, 2009). In all leachate treatment experiments by catalytic ozonation, 900 mL of effluent was used as collected at the landfill site.…”

Landfill leachate treatment with Mn and Ce oxides impregnated GAC–ozone treatment process

“…Therefore, more efficient and economical technologies are needed for the treatment of landfill leachate. For example, some researchers combined ozone with GAC [8], metallic ions [13], and H 2 O 2 [14] to further remove organic contents in landfill leachate.…”