In this study,aluminum-based P-inactivation agent(Al-PIA)was used as a high-efficiency microbial carrier,and the biological Al-PIA(BA-PIA)was prepared by artificial aeration.Laboratory static experiments were conducte...In this study,aluminum-based P-inactivation agent(Al-PIA)was used as a high-efficiency microbial carrier,and the biological Al-PIA(BA-PIA)was prepared by artificial aeration.Laboratory static experiments were conducted to study the effect of BA-PIA on reducing nitrogen and phosphorus contents in water.Physicochemical characterization and isotope tracing method were applied to analyze the removal mechanism of nitrogen and phosphorus.High-throughput techniques were used to analyze the characteristic bacterial genus in the BA-PIA system.The nitrogen and phosphorus removal experiment was conducted for 30 days,and the removal rates of NH_(4)^(+)-N,TN and TP by BA-PIA were 81.87%,66.08%and 87.97%,respectively.The nitrogen removal pathways of BA-PIA were as follows:the nitrification reaction accounted for 59.0%(of which denitrification reaction accounted for 56.4%),microbial assimilation accounted for 18.1%,and the unreacted part accounted for 22.9%.The characteristic bacteria in the BA-PIA system were Streptomyces,Nocardioides,Saccharopolyspora,Nitrosomonas,and Marinobacter.The loading of microorganisms only changed the surface physical properties of Al-PIA(such as specific surface area,pore volume and pore size),without changing its surface chemical properties.The removal mechanism of nitrogen by BA-PIA is the conversion of NH_(4)^(+)-N into NO_(2)^(−)-N and NO_(3)^(−)-N by nitrifying bacteria,which are then reduced to nitrogen-containing gas by aerobic denitrifying bacteria.The phosphorus removal mechanism is that metal compounds(such as Al)on the surface of BA-PIA fix phosphorus through chemisorption processes,such as ligand exchange.Therefore,BA-PIA overcomes the deficiency of Al-PIA with only phosphorus removal ability,and has better application prospects.展开更多
We determined the effects of quartz sand(QS),water treatment plant sludge(WTPS),aluminum-based P-inactivation agent(Al-PIA),and lanthanum-modified bentonite(LMB)thin-layer capping on controlling phosphorus and nitroge...We determined the effects of quartz sand(QS),water treatment plant sludge(WTPS),aluminum-based P-inactivation agent(Al-PIA),and lanthanum-modified bentonite(LMB)thin-layer capping on controlling phosphorus and nitrogen release from the sediment,using a static simulation experiment.The sediment in the experiment was sampled from Yundang Lagoon(Xiamen,Fujian Province,China),which is a eutrophic waterbody.The total phosphorus(TP),ammonium nitrogen(NH4+-N),and total organic carbon(TOC)levels in the overlying water were measured at regular intervals,and the changes of different P forms in WTPS,Al-PIA,and sediment of each system were analyzed before and after the test.The average TP reduction rates of LMB,Al-PIA,WTPS,and QS were 94.82,92.14,86.88,and 10.68%,respectively,when the release strength of sediment TP was 2.26–9.19 mg/(m^(2)·d)and the capping strength of the materials was 2 kg/m^(2).Thin-layer capping of LMB,WTPS,and Al-PIA could effectively control P release from the sediment(P<0.05).However,thin-layer capping of LMB,Al-PIA,and QS did not significantly reduce the release of ammonium N and organic matter(P>0.05).Based on our results,LMB,Al-PIA,and WTPS thin-layer capping promoted the migration and transformation of easily released P in sediment.The P adsorbed by WTPS and Al-PIA mainly occurred in the form of NAIP.展开更多
基金supported by the National Natural Science Fund of China(No.51878300)the Natural Science Foundation of Fujian Province of China(No.2019J01052)the Science and Technology Project Foundation of Xiamen City(No.3502Z20203044).
文摘In this study,aluminum-based P-inactivation agent(Al-PIA)was used as a high-efficiency microbial carrier,and the biological Al-PIA(BA-PIA)was prepared by artificial aeration.Laboratory static experiments were conducted to study the effect of BA-PIA on reducing nitrogen and phosphorus contents in water.Physicochemical characterization and isotope tracing method were applied to analyze the removal mechanism of nitrogen and phosphorus.High-throughput techniques were used to analyze the characteristic bacterial genus in the BA-PIA system.The nitrogen and phosphorus removal experiment was conducted for 30 days,and the removal rates of NH_(4)^(+)-N,TN and TP by BA-PIA were 81.87%,66.08%and 87.97%,respectively.The nitrogen removal pathways of BA-PIA were as follows:the nitrification reaction accounted for 59.0%(of which denitrification reaction accounted for 56.4%),microbial assimilation accounted for 18.1%,and the unreacted part accounted for 22.9%.The characteristic bacteria in the BA-PIA system were Streptomyces,Nocardioides,Saccharopolyspora,Nitrosomonas,and Marinobacter.The loading of microorganisms only changed the surface physical properties of Al-PIA(such as specific surface area,pore volume and pore size),without changing its surface chemical properties.The removal mechanism of nitrogen by BA-PIA is the conversion of NH_(4)^(+)-N into NO_(2)^(−)-N and NO_(3)^(−)-N by nitrifying bacteria,which are then reduced to nitrogen-containing gas by aerobic denitrifying bacteria.The phosphorus removal mechanism is that metal compounds(such as Al)on the surface of BA-PIA fix phosphorus through chemisorption processes,such as ligand exchange.Therefore,BA-PIA overcomes the deficiency of Al-PIA with only phosphorus removal ability,and has better application prospects.
基金supported by the National Natural Science Fund of China(Grant No.51878300)the Natural Science Foundation of Fujian Province of China(Grant No.2019J01052)Project of production,study and research of colleges and universities of Xiamen City(Grant No.3502Z20203044).
文摘We determined the effects of quartz sand(QS),water treatment plant sludge(WTPS),aluminum-based P-inactivation agent(Al-PIA),and lanthanum-modified bentonite(LMB)thin-layer capping on controlling phosphorus and nitrogen release from the sediment,using a static simulation experiment.The sediment in the experiment was sampled from Yundang Lagoon(Xiamen,Fujian Province,China),which is a eutrophic waterbody.The total phosphorus(TP),ammonium nitrogen(NH4+-N),and total organic carbon(TOC)levels in the overlying water were measured at regular intervals,and the changes of different P forms in WTPS,Al-PIA,and sediment of each system were analyzed before and after the test.The average TP reduction rates of LMB,Al-PIA,WTPS,and QS were 94.82,92.14,86.88,and 10.68%,respectively,when the release strength of sediment TP was 2.26–9.19 mg/(m^(2)·d)and the capping strength of the materials was 2 kg/m^(2).Thin-layer capping of LMB,WTPS,and Al-PIA could effectively control P release from the sediment(P<0.05).However,thin-layer capping of LMB,Al-PIA,and QS did not significantly reduce the release of ammonium N and organic matter(P>0.05).Based on our results,LMB,Al-PIA,and WTPS thin-layer capping promoted the migration and transformation of easily released P in sediment.The P adsorbed by WTPS and Al-PIA mainly occurred in the form of NAIP.