Combination of Ozonation and the Fenton Processes for Landfill Leachate Treatment: Evaluation of Treatment Efficiency

摘要

Single processes such as ozonation,ozone /hydrogen peroxide,Fenton and several combined treatment schemes were applied for leachate collected from a waste disposal site. The implementation of combined Fenton and ozonation processes resulted in the highest chemical oxygen demand removal (77% from initial value) among all the treatment methods applied,while biodegradability improvement was observed during the Fenton pre-treatment only. Some decrease of chemical oxygen demand was obtained during the single ozonation or combined schemes including ozone resulting in slight if any biodegradability improvement. The addition of hydrogen peroxide to ozonation did not enhance chemical oxygen demand,dissolved organic carbon or biochemical oxygen demand removal compared to ozone alone. Ferric chloride coagulation used as a pre-treatment stage did not improve subsequent chemical oxygen demand removal by ozonation or the Fenton processes. Taking into account the effective chemical oxygen demand,dissolved organic carbon removal and biodegradability improvement the single Fenton process seems to be a preferable treatment method for the leachate treatment. Some reduction in toxicity to Daphnia magna was observed after the application of the studied treatment methods.