Pilot-scale in situ treatment of landfill leachate using combined coagulation-flocculation, hydrolysis acidification, SBR and electro-Fenton oxidation.

The treatment of a landfill leachate was developed at the pilot scale using a combination of processes, including coagulation, hydrolysis acidification (HA)-sequence batch reactors (SBR) and electro-Fenton oxidation in series. The aim was to enhance the removal of pollutants in the landfill leachate, which contained high organic and NH3-N loadings. During the 156-day in situ operation, the average removal efficiency of the chemical oxygen demand (COD) was 97.8% and the lowest effluent COD was 78 mg/L. The removal efficiencies of colour, turbidity and total phosphorus were all higher than 97%. The overall operating cost was US$ 4.84/m3. This combined process showed a high potential to efficiently remediate landfill leachate at an acceptable expense.