Study On Ozone And Fe₂O₃ Nanomodified Pumice Enhanced UASB Reactor For Treated Incineration Leachate

The UASB reactor has advantages such as low sludge production,high organic matter removal efficiency,recoverable biogas,and low operating costs.However,it also has problems such as long start-up time,poor resistance to load shock,and easy acidification.These problems seriously affect wastewater treatment efficiency.To solve these problems,this study used ozone and Fe₂O₃ nanomodified pumice to enhance the UASB reactor for treating incineration leachate.The effects of ozone and Fe₂O₃ nanomodified pumice on the start-up performance and load shock resistance of UASB reactor were studied.The main research results are as follows:.The main research results are as follows:（1）The reactor with added Fe₂O₃ nanomodified pumice completed start-up 12 days earlier than the control reactor and produced granular sludge 15 days earlier.Its maximum organic load was 49.77 kg COD/（m³·d）,2.76 times that of the control group reactor.Fe₂O₃nanomodified pumice increased bacterial and archaea diversity and abundance,stimulated interspecies electron transfer,enhanced methanogen growth activity,promoted anaerobic methanogenesis process,reduced VFA accumulation and maintained a more stable p H and ORP environment in anaerobic system.（2）The ozone pretreatment reactor completed start-up 12 days earlier than the control reactor and produced granular sludge 15 days earlier.Its maximum organic load was 25.08kg COD/（m³·d）,1.39 times that of the control group reactor.Ozone pretreatment reduced the inhibitory effect of leachate on microorganisms,increased bacterial and archaea diversity and abundance in the reactor,enhanced microbial growth activity and improved anaerobic digestion efficiency.As a result,the UASB reactor completed start-up in a shorter time and could withstand higher organic loads.（3）The ozone pretreatment and added Fe₂O₃ nanomodified pumice reactor completed start-up 18 days earlier than the control reactor and produced granular sludge 15 days earlier.Its maximum organic load was 57.3 kg COD/（m³·d）,3.18 times that of the control reactor.The synergistic effect of ozone and Fe₂O₃ nanomodified pumice not only reduced the biotoxicity of leachate but also stimulated interspecies electron transfer,increased bacterial and archaea diversity and abundance in the reactor,enhanced methanogen growth activity,promoted anaerobic methanogenesis process,reduced VFA accumulation and maintained a more stable p H and ORP environment in anaerobic system.As a result,the UASB reactor completed start-up in a shorter time and could withstand higher organic loads while maintaining more stable operating conditions.In a conclusion,added Fe₂O₃ nanomodified pumice or ozone pretreatment can shorten UASB reactor start-up time and improve resistance to load shock.Among them,added Fe₂O₃nanomodified pumice has a stronger effect on enhancing the anaerobic performance of the UASB reactor under high load shock than ozone pretreatment.The combined use of ozone and Fe₂O₃ nanomodified pumice has a better enhancement effect on the UASB reactor than either alone.Figure[102]table[13]reference[125]...