This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days...This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days in parallel,results indicated that the conversion rate of N2O for a magnetic field-sequencing batch reactor(MF-SBR)decreased by34.3%compared to that of a conventional SBR(C-SBR).Meanwhile,the removal efficiencies for total nitrogen(TN)and ammonia nitrogen(NH4-N)of the MF-SBR were 22.4%and 39.5%higher than those of the C-SBR.High-throughput sequencing revealed that the abundances of AOB(Nitrosomonas),NOB(Nitrospira)and denitrifiers(Zoogloea),which could reduce N2O to N2,were promoted significantly in the MF-SBR.Enzyme activities(Nir)and gene abundances(nos Z nir S and nir K)for denitrification in the MF-SBR were also notably higher compared to C-SBR.Our study shows that application of a magnetic field is a useful approach for inhibiting the generation of N2O and promoting the nitrogen removal efficiency by affecting the microbial characteristics of sludge in an SBR treating domestic wastewater at low temperature.展开更多
基金supported by the Major Science and Technology Program for Water Pollution Control and Treatment(No.2017ZX07202-001-002)
文摘This study aims to investigate the effect of a magnetic field on nitrous oxide(N2O)emission from a sequencing batch reactor treating low-strength domestic wastewater at low temperature(10℃).After running for 124 days in parallel,results indicated that the conversion rate of N2O for a magnetic field-sequencing batch reactor(MF-SBR)decreased by34.3%compared to that of a conventional SBR(C-SBR).Meanwhile,the removal efficiencies for total nitrogen(TN)and ammonia nitrogen(NH4-N)of the MF-SBR were 22.4%and 39.5%higher than those of the C-SBR.High-throughput sequencing revealed that the abundances of AOB(Nitrosomonas),NOB(Nitrospira)and denitrifiers(Zoogloea),which could reduce N2O to N2,were promoted significantly in the MF-SBR.Enzyme activities(Nir)and gene abundances(nos Z nir S and nir K)for denitrification in the MF-SBR were also notably higher compared to C-SBR.Our study shows that application of a magnetic field is a useful approach for inhibiting the generation of N2O and promoting the nitrogen removal efficiency by affecting the microbial characteristics of sludge in an SBR treating domestic wastewater at low temperature.