Complete nitrogen removal was achieved through integrating anammox and autotrophic denitrification in an UASB reactor.The total nitrogen(TN)removal rate increased stepwise from 0.46 to 0.94 kg-N/(m3·d),with an ef...Complete nitrogen removal was achieved through integrating anammox and autotrophic denitrification in an UASB reactor.The total nitrogen(TN)removal rate increased stepwise from 0.46 to 0.94 kg-N/(m3·d),with an effluent TN concentration of below 3.0 mg-N/L achieved.The process is relatively insensitive to the nitrite to ammonium ratio,achieving complete nitrogen removal when their ratio in the influent varied in the range of 1.35-1.55.The added S0 quantity in the system could be utilized to adjust the competition between autotrophic denitrifiers and anammox bacteria.High-throughput sequencing technology indicated that Candidatus_Kuenenia and Thiobacillus were the functional strains for anammox and autotrphic denitrification process,respectively,in the studied reactor.This result provides a theoretical and technical basis for the large-scale application of anaerobic ammonium oxidation process.展开更多
In this study,the enhanced mineralization of p-fluoronitrobenzene(p-FNB)was achieved in a methane-based hollow-fiber membrane biofilm reactor(CH4-MBfR).A TOC removal of 73.2%was gained in CH4-MBfR with an influent p-F...In this study,the enhanced mineralization of p-fluoronitrobenzene(p-FNB)was achieved in a methane-based hollow-fiber membrane biofilm reactor(CH4-MBfR).A TOC removal of 73.2%was gained in CH4-MBfR with an influent p-FNB loading of 42―84 mg/L·d,while only 40.6%of TOC was removed in the corresponding control biological reactor(BR).Moreover,the reaction rate constant for TOC removal in CH4-MBfR was 2.48 times that of the BR.VFAs was only detected in CH4-MBfR,although oxidation elimination was the first step for p-FNB removal in both systems.Methylococcus and Methylononas were dominant strains in the CH4-MBfR,which may play an important role in converting CH4 to VFAs and then further enhancing the mineralization efficiency of p-FNB.展开更多
In this study,nitrogen removal performance of the denitrifying ammonium oxidation(DAO)process was investigated when treating sulfamethoxazole(SMX)-laden secondary wastewater effluent.The influent SMX concentration sho...In this study,nitrogen removal performance of the denitrifying ammonium oxidation(DAO)process was investigated when treating sulfamethoxazole(SMX)-laden secondary wastewater effluent.The influent SMX concentration showed negligible effect on efficiencies for removal of nitrate and COD.However,the ammonium ions removal rate was moderately reduced,when the influent SMX concentration in wastewater reached 6 mg/L.Total nitrogen removal efficiency remained as high as 76.77%towards the day 158 at the end of experiment.Candidatus_Brocadia and Candidatus_Kuenenia were the functional anammox strains.The unclassified_f__Rhodobacteraceae sp.was predominant heterotrophic denitrifying strain in the studied reactor.The concentrations of soluble extracellular polymeric substances in sludge obviously increased from 16.76 mg/g VSS to 32.31 mg/g VSS,which might protect the nitrogen removal strains from high-concentration SMX.This result provides a theoretical and technical foundation for the application of denitrifying ammonium oxidation process in treating sulfamethoxazole-laden secondary wastewater effluent.展开更多
基金This research was supported by the National Natural Science Foundation of China(No.21307160)the Shandong Provincial Natural Science Foundation,China(No.ZR2019MEE038)+2 种基金the Fundamental Research Funds for the Central Universities(19CX02038A)the Open Project of Key Laboratory of Environmental Biotechnology,CAS(Grant No.kf2018003)the Open Project Program of State Key Laboratory of Petroleum Pollution Control(Grant No.PPC2018006),CNPC Research Institute of Safety and Environmental Technology.
文摘Complete nitrogen removal was achieved through integrating anammox and autotrophic denitrification in an UASB reactor.The total nitrogen(TN)removal rate increased stepwise from 0.46 to 0.94 kg-N/(m3·d),with an effluent TN concentration of below 3.0 mg-N/L achieved.The process is relatively insensitive to the nitrite to ammonium ratio,achieving complete nitrogen removal when their ratio in the influent varied in the range of 1.35-1.55.The added S0 quantity in the system could be utilized to adjust the competition between autotrophic denitrifiers and anammox bacteria.High-throughput sequencing technology indicated that Candidatus_Kuenenia and Thiobacillus were the functional strains for anammox and autotrphic denitrification process,respectively,in the studied reactor.This result provides a theoretical and technical basis for the large-scale application of anaerobic ammonium oxidation process.
基金This research was supported by the National Natural Science Foundation of China(No.21307160)the Natural Science Foundation of Shandong Province(ZR2019MEE038)the Fundamental Research Funds for the Central Universities(19CX02038A).
文摘In this study,the enhanced mineralization of p-fluoronitrobenzene(p-FNB)was achieved in a methane-based hollow-fiber membrane biofilm reactor(CH4-MBfR).A TOC removal of 73.2%was gained in CH4-MBfR with an influent p-FNB loading of 42―84 mg/L·d,while only 40.6%of TOC was removed in the corresponding control biological reactor(BR).Moreover,the reaction rate constant for TOC removal in CH4-MBfR was 2.48 times that of the BR.VFAs was only detected in CH4-MBfR,although oxidation elimination was the first step for p-FNB removal in both systems.Methylococcus and Methylononas were dominant strains in the CH4-MBfR,which may play an important role in converting CH4 to VFAs and then further enhancing the mineralization efficiency of p-FNB.
基金This research was supported by the Natural Science Foundation of Shandong Province(ZR2019MEE038)the Fundamental Research Funds for the Central Universities(19CX02038A).
文摘In this study,nitrogen removal performance of the denitrifying ammonium oxidation(DAO)process was investigated when treating sulfamethoxazole(SMX)-laden secondary wastewater effluent.The influent SMX concentration showed negligible effect on efficiencies for removal of nitrate and COD.However,the ammonium ions removal rate was moderately reduced,when the influent SMX concentration in wastewater reached 6 mg/L.Total nitrogen removal efficiency remained as high as 76.77%towards the day 158 at the end of experiment.Candidatus_Brocadia and Candidatus_Kuenenia were the functional anammox strains.The unclassified_f__Rhodobacteraceae sp.was predominant heterotrophic denitrifying strain in the studied reactor.The concentrations of soluble extracellular polymeric substances in sludge obviously increased from 16.76 mg/g VSS to 32.31 mg/g VSS,which might protect the nitrogen removal strains from high-concentration SMX.This result provides a theoretical and technical foundation for the application of denitrifying ammonium oxidation process in treating sulfamethoxazole-laden secondary wastewater effluent.
