Synergistic Removal Research On Refractory Organics And TN In Matter Landfill Leachate

This research studied on the mature landfill leachate,which have the characteristics with high concentration and difficult-treatment organic waste water with large change in water quality and a small proportion of microbial nutrient elements.The components of mature landfill leachate are very complicated with large variation range.The concentration of COD and NH₄⁺-N is high and containing humic substance which is difficult to biodegrade.Biological treatment technology has a good treatment effect on the young landfill leachate,however the single biological treatment technology still has a large problem for the treatment of mature landfill leachate in the middle and late stage.Treatment technique of organic waste water and ammonia nitrogen are hard to be degraded.It is usually used to pretreat leachate by physical-chemical method,or secondary treatment of effluent,and the treatment process of pretreatment or secondary treatment combined with biological treatment technology are complicated and low economic benefit,which is not conducive to large-scale application.In this study,UASB1-A/O-UASB2 advanced treatment system was used to carry out in-depth treatment of the landfill leachate,and the simultaneous removal of organic matter and TN was completed while saving cost and carbon source.The main results of the analysis of the main dominant bacteria in UASB1 reactor and UASB2 reactor were analyzed by means of molecular biology as follows.?1?The optimum pH range of the UASB1-A/O-UASB2 depth treatment system is 7.5⁸.3,and the optimal DO concentration of A/O pool is 0.5¹.5mg/L.The optimal ORP range-200^-300mv,COD,TN removal rate reached 95.08%and 66.73%respectively,which realized the simultaneous removal of organic matter and nitrogen in landfill leachate.In UASB2 reactor,the functional groups related to carboxyl,amide and benzene ring were reduced,and the functional groups related to the aliphatic group increased.Humus utilization priority:class tryptophan>humic acid>type tyrosine>class fulvic acid;?2?UASB1 reactor of denitrification process in superiority strains tow bacteria genera and other function of denitrifying bacteria by combined action,under the action of superiority strains uncultered bacterium norank Bacteroidetes vadinHA17,anaerobic bacteria genera bacteria and other microorganisms with anaerobic digestion reaction.In the UASB2 reactor,Denitratisoma and other microorganisms were involved in the denitrification process,and the remaining refractory humus substances in the dominant species were clostridium which accounts for 35.19%or uncultered bacterium norank Bacteroidetes vadinHA17 bacteria and other microorganisms,which could be used to provide carbon source material for the denitrification process,thus reducing the degradation of humus concentration.?3?Nncultered bacterium norank Bacteroidetes vadinHA17 was used as inoculation sludge and the only dominant strain in the UAB1 reactor and UASB2 reactor,which the relative abundance ratio was 26.20%,10.66%and 3.28%respectively.Furthermore,it had an important effect on the complex and refractory organic compounds,such as the degradation of humus and other complex organic carbon sources.