Photo-Fenton process for removal of polycyclic aromatic hydrocarbons from hazardous waste landfill leachate

The efficiency of Fenton’s oxidation was assessed in this study for hazardous waste landfill leachate treatment. The two major reagents, which are generally employed in Fenton’s process are H2O2 as oxidizing agent and Fe2+ as catalyst. Batch experiments were conducted to determine the effect of experimental conditions viz., reaction time, molar ratio, and Fenton reagent dosages, which are significant parameters that influence the degradation efficiencies of Fenton process were examined. It was found that under the favorable experimental conditions, maximum COD removal was 56.49%. The optimum experimental conditions were pH=3, H2O2/Fe2+ molar ratio = 3 and reaction time = 150 minutes. The optimal amount of hydrogen peroxide and iron were 0.12 mol/L and 0.04 mol/L respectively. High dosages of H2O2 and iron resulted in scavenging effects on OH• radicals and lowered degradation efficiency of organic compounds in the hazardous waste landfill leachate.

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Hazardous waste landfill leachate treatment by combined chemical and biological techniques

Desalination and Water Treatment ◽

10.1080/19443994.2015.1057539 ◽

2015 ◽

Vol 57 (28) ◽

pp. 13236-13245 ◽

Cited By ~ 10

Author(s):

Eneliis Kattel ◽

Arthur Kivi ◽

Kati Klein ◽

Taavo Tenno ◽

Niina Dulova ◽

...

Keyword(s):

Hazardous Waste ◽

Landfill Leachate ◽

Leachate Treatment ◽

Waste Landfill ◽

Hazardous Waste Landfill

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The BIOZO process – a biofilm system combined with ozonation: occurrence of xenobiotic organic micro-pollutants in and removal of polycyclic aromatic hydrocarbons and nitrogen from landfill leachate

Water Science & Technology ◽

10.2166/wst.2010.920 ◽

2010 ◽

Vol 61 (12) ◽

pp. 3188-3197 ◽

Cited By ~ 14

Author(s):

Benedek Gy. Plósz ◽

Christian Vogelsang ◽

Kenneth Macrae ◽

Harald H. Heiaas ◽

Antonio Lopez ◽

...

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Nitrogen Removal ◽

Aromatic Hydrocarbons ◽

Landfill Leachate ◽

Effective Means ◽

Pilot Scale ◽

Biofilm Reactor ◽

Priority List ◽

Polycyclic Aromatic ◽

Micro Pollutants

We present an assessment of xenobiotic organic micro-pollutants (XOM) occurrence and removal of polycyclic aromatic hydrocarbons (PAHs) in a novel biofilm system combined with ozonation, the BIOZO concept, treating partly stabilised landfill leachate. A novel, staged moving-bed biofilm reactor (SMBBR) design was implemented in laboratory- and pilot-scale, and the PAHs removal efficiency of controlled ozonation was assessed installing the ozonation step in the nitrate recirculation line (Position 1) or between the pre-anoxic and aerobic zones (Position 2). COD removal in a laboratory- and in a pilot-scale SMBBR system with and without ozonation is additionally addressed. Results obtained in a screening study (GC-ToF-MS) were used to compile a priority list of XOMs in leachate based on relative occurrence, showing PAHs as the predominant fraction. Biological treatment is shown to be an effective means to remove PAHs detected in the aqueous phase. PAH removal takes in most part place in the pre-anoxic zone, thereby decreasing toxicity exhibited by PAH on autotrophic nitrifier bacteria in the aerobic zone. Ozonation installed in Position 2 is shown to be superior over Position I in terms of COD, PAH and nitrogen removal efficiencies. We additionally demonstrate the potential of intermittent sludge ozonation as a means to decrease PAH concentrations in sludge wasted and to improve nitrogen removal in the BIOZO system.

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