Search for: All records

Landfill leachate contains high levels of dissolved organic nitrogen (DON) that can be detrimental to aquatic life and water quality because it promotes the growth of harmful algal blooms (HABs). This study used physicochemical treatment technologies such as Fenton treatment and Granular Activated Carbon (GAC) adsorption to assess the breakdown and removal of landfill leachate-induced DON. The physicochemical treatments were applied to effluents of two bioreactors treating blended wastewater and landfill leachate. Bioreactor-1 (R1) was fed with high organic landfill leachate, and bioreactor-2 (R2) was fed with low organic landfill leachate. For R1 effluent, the Fenton treatment removed 66±9.2% COD and 52.4±8.7% DON at an optimum dosage of 200mg/L H2O2 and 1000mg/L FeSO4.7H2O. On the other hand, GAC removed 94.4±4.9% COD and 85.9±4.6% DON at an optimum dosage of 10g/L GAC. For R2 effluent, the Fenton treatment removed 75.8±6.6% COD and 60.3±3.2% DON at an optimum dosage of 200mg/L H2O2 and 1000mg/L FeSO4.7H2O. On the contrary, GAC treatment removed 92.2±4.3% COD and 92.3±3.7% DON at an optimum dosage of 10g/L GAC. Moreover, fluorescence spectrophotometry combined with parallel factor analysis (PARAFAC) was employed to provide insight into the DON degradation mechanisms. The study found that Fenton treatment and GAC adsorption both can effectively reduce DON in landfill leachate. However, GAC treatment was superior to Fenton treatment in eliminating DON from landfill leachate, while Fenton treatment may convert DON into inorganic nitrogen. The study emphasizes properly handling landfill leachate to avoid nitrogen contamination and harmful algal blooms in aquatic ecosystems.