Treatment of mature landfill leachate by a continuous modular internal micro-electrolysis Fenton reactor

A modular internal micro-electrolysis Fenton reactor (MIME-Fenton) was specifically designed in order to facilitate the performance of internal micro-electrolysis (IME) technology in the treatment of mature landfill leachate. Excellent COD removal efficiency of 90.9 % by the new reactor of mature landfill leachate was observed in bench-scale treatment, which is 193–399, 415–551, and 226–457 % higher than that of conventional treatments of electrolysis, coagulation–sedimentation, and Fenton, respectively. The innovative concept behind the excellent performance is the novel two-step treatment, similar to the anaerobic–aerobic activated sludge method. It is based on a combination effect of reductive IME and oxidative IME with aeration processes and the integration of electro-aggregation and electro-coagulation. Initial pH and air flow rate were optimized, and the effect of auxiliary in situ regeneration of ferrous iron and generation of H2O2 was further investigated. The reactor was also particularly efficient in removal of color and HA, and in improvement of the BOD5/COD ratio. All these results show that the MIME-Fenton reactor, a new approach of IME, is promising for mature landfill leachate treatment because it is efficient and easy to operate.