| Leachates from municipal solid waste landfill sitesare often defined asheavily polluted wastewaters. Leachates may contain large amounts of organic matter,where CODCr consist an important group, as well as ammonia-nitrogen, heavy metals.Landfill leachates have been identified as potential sources of ground and surfacewaters contamination, if they are not safely disposed. So it is a hard work to properlytreat the landfill leachates.The research of applying microelectrolysis-chemical precipitation-adsorptionmethod to treat the landfill leachate was introduced in this paper. The concentration ofCODCr and ammonia-nitrogen of the landfill leachate were 2500-3000mg/L,1200-1500mg/L. The optimal conditions were got during the experiments. The testresults show:The removal rate of CODCr is 86.46ï¼…at the HRT of 80min, the pH of 3.5 duringthe micro-electrolysis. The removal rate of CODCr is 79.38ï¼…at the H2O2 dosage of13g/L, the pH of 3.0, the reaction time of 15 min during the Fenton reagent oxidation.When pH at 9.0, magnesium ammonium and phosphate molar ratios of 1.2:1:1.2, andthe reaction time is 15min, the removal efficiency of ammonia-nitrogen is above 98ï¼…and the residual phosphate is 26.44 mg/L during the MAP chemical precipitation. Theremoval rate of CODCr and ammonia-nitrogen is 23.78ï¼…and 39.22ï¼…respectively atthe bentonite dosage of 24g/L, the pH of 7.0, the reaction time of 60 min during theadsorption.The CODCr and ammonia-nitrogen can be decreased to 330.85 mg/L and 8.25mg/L respectively by the microelectrolysis-chemical precipitation-adsorption method.The total removal rate of CODCr and ammonia-nitrogen is 88.73ï¼…and 99.38ï¼…respectively.This study provided test data and design reference for engineering practice totreat the landfill leachate by microelectrolysis-chemical precipitation-adsorption.
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