Investigation of landfill leachate treatment by advanced oxidation processes

Landfilling is currently the primary method for solid waste disposal in the world. Landfill leachate is one the most important source of toxic organic compound for ground and surface waters. Generally landfill leachate treatment is focused on the removal of organic matter (commonly COD) and nitrogen as well as toxic substances during treatment. Several physical and chemical methods have been suggested for the treatment of municipal landfill leachates in the past three decades, including coagulation–flocculation, chemical precipitation, ammonium stripping, membrane filtration (nanofiltration, reverse osmosis), activated carbon adsorption, ion exchange and electrochemical treatment. In fact method selection depends on the characteristics of leachates such as age of landfill, ratio of biological oxygen demand, chemical oxygen demand BOD/COD, and absolute amount of COD. This article reviews methods for treatment of landfill leachates and focuses on advanced oxidation processes (AOPs). These processes have been employed for the treatment of landfill leachate and can be used to eliminate refractory organic compound from wastewaters.