Research On Treatment Technology Of DaYi’s Membrane Filter Concentrate Liquor From Landfill Leachate

As the standard of environmental protection enhanced, Membrane separationtechnology is acted as the effective way to dispose landfill leachate and producesamount of membrane filter concentrate liquor inevitably. International researchesindicate that the superior difficulty in processes, high price and other factors aboutmembrane filter concentrate liquor made it difficult to execute the utilization ofmembrane separation technology. Thus it is imperative to research and develop efficient,low-cost, easy manipulative and no second-polluted methods.The main investigativeindexs rested with COD_cr，chromaticity color and turbidity.This research is focused on the available physical-chemistry processes todecontaminate membrane filter concentrate liquor from landfill leachate in DaYi.Flocculation has been used as the pretreatment in processing phase of membranefilter concentrate liquor.As the results show that the optimum treatment process isdraining from the preliminary flocculation by4000ppm FeCl₃in membrane filterconcentrate liquor,then adjust the pH value to3or8before adding2000ppm waste slagahead of25ppm GF and100ppm BTF respectively. Even the turbidity is removedcompletely, but the COD_crvalue still linger about650mg/L.In need of further treatment.BTF has uniform and orderly reticulate structure manifested to be firm and compacte,which exists branched chain instead of graininess.The further processes include electrolyzation in three-dimension or two-dimensionand ozonation. From correlated oxidation test we can conclude the optimal preparationconditions of each catalysts.Titrated by0.05mol/L Ce（NO₃）₃and0.1mol/L H₂C₂O₄before coated the precipitateon the graphite. After been calcinated for4h under723K,the deposition sedimentation-based CeO₂/graphite electrode created. Impregnated in0.005mol/LH₂C₂O₄and0.01mol/L Ce（NO₃）₃successively with graphite. Followed by calcinatingfor4h under823K,the complexation type CeO₂/graphite electrode has been obtained.Those two kinds of catalysts have small particle size which is less than15nm.Bycontrast, the crystal particle of deposition sedimentation-based CeO₂/graphite electrodeis much more littery and incomplete in growth. The preparation of complexation typeCeO₂/γ-Al₂O₃catalyst is similar to the complexation type CeO₂/graphite elrode，thedifferences lie in0.04mol/L H₂C₂O₄,0.06mol/L Ce（NO₃）₃and calcination time lastingfor5h. The removal rate of COD_crby using each one of these three catalysts are allbeyond50%. Besides,the catalytic activity of complexation CeO₂/γ-Al₂O₃is Slightlyless than the Impregnation one,but its reusability shows superiority, and has biggeraverage grain diameter.For the use of ozonation,the preparation of complexation type La-Mn/γ-Al₂O₃catalyst is similar to the complexation type CeO₂/graphite elrode,except that0.045mol/LH₂C₂O₄,0.025mol/L La-Mn（1:1）which pH value is11, calcinating for2h under723K.The removal efficiency of HA can reach47.59%after ozonizing for30min withthe kind of catalyst.The active components has completely loaded in theγ-Al₂O₃,formeda much more uniform and orderly microstructure.The integrated treatment processes of this membrane filter concentrate liquor canbe verified as follows: pretreatment-flocculation then advanced oxidation byelectrolyzation for3h accompany with6.4A/dm²electric current density bycomplexation CeO₂/graphite electrode. The COD_crvalue and chromaticity color ofeffluent can attain the national primary standard.