Study on the application of Effective Microorganism technology in landfill leachate treatment

A large quantity of landfill leachate with many kinds of toxic and harmful substances produced during the degradation process of solid waste in landfill can cause serious environmental pollution, so it is important to find out an available technology to solve this problem. The use of Effective Microorganisms (EM) technology for reducing organic pollutant of landfill leachate has often been suggested as a feasible method in landfills, but the activity of EM can be influenced by surroundings such as aerobic or anaerobic, temperature, pH and the addition of volume rate between EM and landfill leachate. Laboratory tests show that the efficiency of the treatment of landfill leachate by EM technology reaches the highest rate under the condition of aerobic, 25 similar to 35 degrees C, pH 7.0 similar to 8.0 and 1/2000 similar to 1/1000 volume ratio between EM and landfill leachate, the removal rate of Chemical Oxygen Demand (COD) and ammonium nitrogen (NH3-N) of landfill leachate is about 60% after 10 days of the treatment. Under anaerobic conditions as control subjects, COD of landfill leachate with EM can not reduce, while the concentration of NH3-N increased because of the effect of denitrification. It must be noted that the COD of EM is over 20,000 mg/L, if the proportion of EM and leachate is too high, the COD of leachate may increase in opposition to what is expected, so the addition of volume rate between EM and landfill leachate should be tested to content with the various demands of the special purposes by a laboratory study before applying it in landfills.