| Partial nitrification and Anaerobic Ammonia Oxidation,as emerging biological denitrification processes in recent years,have the advantages of low energy consumption and high denitrification efficiency,and have wide prospects in the field of ammonia-rich wastewater treatment.High ammonia nitrogen wastewater is characterized by complex composition and high concentration of pollutants,which is gradually gaining attention in the field of wastewater treatment.The presence of emerging pollutants such as antibiotics and higher concentration of organic matter in the actual ammonia-nitrogen wastewater,the toxicity and difficult degradability of antibiotics limit the engineering application of partial nitrification process and anaerobic ammonia oxidation process.Therefore,it becomes critical to explore the effect of antibiotics on nitrogen removal and to seek the tolerance level of both processes to antibiotics,and it is essential to conduct research on the removal of organic matter in partial nitrification and anaerobic ammonia oxidation processes.In this study,we further enriched anaerobic ammonia oxidizing bacteria(An AOB)and ammonia oxidizing bacteria(AOB)with high activity based on laboratory rapid start-up process of nitrification and anaerobic ammonia oxidation process.On this basis,we investigated the effects of different concentrations of antibiotic sulfamethoxazole and general organic matter on the performance,single and composite of partial nitrification and anaerobic ammonia oxidation systems using high nitrogen wastewater containing antibiotics as the research object.The changes of fluorescent substances in the reactor effluent were monitored using parallel factor analysis combined with three dimensional fluorescence technique.The main experimental findings were as follows:1.The partial nitrification system was optimized by dissolved oxygen and hydraulic residence time and was successfully started after 30 days of regulation and operation.p H 8.0±0.3,DO 0.5-0.8 mg/L,aeration stirring 3.5 h,temperature 30±0.5℃ is the best condition of partial nitrification process,the stable operation when DO 0.5 mg/L ammonia nitrogen removal rate increased rapidly,up to 98.40%,nitrite accumulation rate also gradually increased,the maximum value reached 95.37%.2.Explore the feasibility of the rapid start of anaerobic ammonia oxidation reactor in sealed storage at room temperature.Only 53 d successfully started the anammox reactor,and the initiation period is mainly divided into four stages,namely,the autolysis period,the activity stagnation period,the proliferation period and the active stability period.After 70 d of reactor cultivation,the average removal rate of nitrite nitrogen was 98.06%.3.The increase of the concentration of sulfamethoxazole affects the denitrification performance of anammox and partial nitrification process.When the concentration of sulfamethoxazole is 0.2 mg/L,there is almost no effect on the two processes;when the concentration of sulfamethoxazole is increased to 2.0 mg/L,the partial nitrification process is obviously affected by the concentration change,but the excellent operation effect can be restored quickly,and the overall performance of ammonia oxidation process is inhibited,especially the removal effect of ammonia nitrogen becomes worse.Short-range nitration tolerated sulfamethoxazole at higher concentrations(> 2.0 mg/L)and removed part of sulfamethoxazole,while anammox tolerated only low concentrations(< 2.0 mg/L).4.Explore the nitrogen removal performance of partial nitrification and anamidine oxidation reactor under different organic shock loads.When the COD concentration is more significant than 140 mg/L,the nitrogen removal performance of both partial nitrification and anaerobe oxidation is impaired.The concentration of nitrite nitrogen in anammox reactor is very low,and the removal rate is about 99%.With the increasing COD concentration,the concentration of nitrite produced by partial nitrification and ammonia oxidation process decreased rapidly.5.Three-dimensional fluorescence spectroscopy combined with parallel factor analysis was used to analyze the composition and change of the fluorescent substance during the reactor effluent and operation.The results are as follows: when organic matter is added,the effluent water of the partial nitrification reactor mainly contains humic acid,humic acid and protein-like substances,and the rich acid-like substances,humic acid and protein-like substances in the effluent of the anaerobe oxidation reactor.With the increasing concentration of organic carbon source,protein-like substances become the main fluorescent substances in the effluents of the reactor.Figure [30] table [12] reference [102]... |
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