A Study On The Treatment Of Landfill Leachate By Combination Of Semi-aerobic Aged Refuse Biofilter And Ozone Oxidation Technology

With the acceleration of urbanization and the improvement of residents’living standard,the production of urban household garbage is increasing day by day.Landfill technology is the foremost method for the treatment and disposal of municipal solid waste in China and efficient landfill leachate treatment methods make it up to standard discharge is still a problem that needs to be solved urgently.To provide some reference for the advanced treatment of leachate,this paper use ozone oxidation process some elderly and young leachate of landfill site after quasi aerobic bed mineralized garbage treatment of tail water,discusses the old and young garbage leachate in dissolving organic matter in aerobic mineralized garbage bed joint ozone advanced oxidation system transformation mechanism,and by investigating O₃,GAC and H₂O₂ dosing amount,initial pH value of GAC-O₃/H₂O₂ system deals with the influence of aging leachate tail water,parsing the refractory organics in the GAC-O₃/H₂O₂ system transformation mechanism.Through comparison of experimental data find out that the proportion of macromolecule organics in aged landfill leachate stocks is much higher than that of young landfill leachate.The content of aromatic compounds and organic compounds containing chromophore groups in the leachate of old landfill leachate is also much higher than that of young leachate.Experiments show that the semi-aerobic aged refuse biofilter have better pretreatment effect on landfill leachate,but the humus substances in the biofilter will be discharged along with the leachate,and the degree of humification of dissolved organic matter in tail water of leachate can be enhanced,and mineralization can be achieved.Trash and tail water is less biodegradable and is no longer suitable for biological treatment.Ozone can oxidize the aromatic substances in landfill leachate tail water.Ozone treatment of old and young leachate tail water will reduce the aromaticity and hydrophobicity of organic matter in leachate tail water and greatly increase biodegradability.The chemical stability of dissolved organics in tail water of old landfill leachate is stronger,so the treatment effect of ozone on young landfill leachate tail water is better than that of old land leachate.The experimental results shows that when the leachate effluent is treated by H₂O₂ and GAC catalytic ozone oxidation,in 10 g/L GAC dosing quantity,32.16 mg/min O₃ dosing quantity,3 ml/L H₂O₂ dosing quantity,and the initial pH is 5,reaction after 20 min,the leachate of tail water COD and UV₂₅₄ fell to 393.85 from 700.08 mg/L,and 0.244 from 0.488,the UV₂₅₄ and COD removal rate is 43.80%and 50.00%respectively.After the GAC-O₃/H₂O₂system processing the old leachate tail water,the peak values of fulvic-like in ultraviolet region and fulvic-like in visible region remarkably reduced,the humus in the tail water is destroyed and mineralized.