Two full-scale systems operated in parallel, a conventional A2/O system consisting of anaerobic, anoxic and oxic compartments in succession and an inverted system consisting of anoxic, anaerobic and oxic compartments ...Two full-scale systems operated in parallel, a conventional A2/O system consisting of anaerobic, anoxic and oxic compartments in succession and an inverted system consisting of anoxic, anaerobic and oxic compartments without internal recycle, were compared in terms of their phosphorus removal performance, with an emphasis on phosphate （P） release behaviors, using both operational data and simulation results. The inverted system exhibited better long-term phosphorus removal performance （0.2 ± 0.3 vs. 0.7 ±0.7 mg/L）, which should be attributed to the higher P release rate （0.79 vs. 0.60 kg P/（kg MLSS.day）） in the non-aerated compartments. The P release occurred in both the anoxic and anaerobic compartments of the inverted system, resulting in more efficient P release. Although the abundances of the ＇Candidatus Accumulibacter phosphatis＇ population in the two systems were quite similar （（19.1 ＋ 3.27）% and （18.4 ＋ 4.15）% of the total microbe （DAPI stained particles） population in the inverted and conventional systems, respectively, by fluorescence in situ hybridization （FISH））, the high-concentration DAPI staining results show that the abundances of the whole polyphosphate accumulating organisms （PAOs） in the aerobic ends were quite different （the average ratios of the poly-P granules to total microbes （DAPI stained particles） were （45 ±4.18）% and （35 ± 5.39）%, respectively）. Both the operational data and simulation results showed that the inverted system retained more abundant PAO populations due to its special configuration, which permitted efficient P release in the non-aerated compartment and better P removal,展开更多
Full scale experimental study on nitrogen removal for low-carbon wastewater was conducted in reversed A2/O process in Jiguanshi waste water treatment plant in Chongqing,in order to aid the operation and maintenance of...Full scale experimental study on nitrogen removal for low-carbon wastewater was conducted in reversed A2/O process in Jiguanshi waste water treatment plant in Chongqing,in order to aid the operation and maintenance of similar WWTP. When the proposed measures,such as using 0.1% (volume fraction of wastewater) landfill leachate,shortening HRT by 2/3 in the primary sedimentation tank and controlling DO at 0.5 mg/L in the 3rd section of aerobic zone,are applied,15% of the carbon source can be complemented,the favorable property of activated sludge is achieved,and the nitrogen removal effect is significantly improved. The effluent NH3-N is 2 mg/L and the removal rate is 90%. The effluent TN is 17 mg/L and the removal rate is 54%. The up-to-standard discharge of the effluent is achieved. And after the optimization,the unit electricity consumption also reaches 0.21 kW/h and saves 20%.展开更多
Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the ...Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal.展开更多
基金supported by the National Natural Science Foundation of China (No. 20921140094)the Knowledge Innovation Project of Chinese Academy of Sciences(No. KSCX2-YW-G-054)
文摘Two full-scale systems operated in parallel, a conventional A2/O system consisting of anaerobic, anoxic and oxic compartments in succession and an inverted system consisting of anoxic, anaerobic and oxic compartments without internal recycle, were compared in terms of their phosphorus removal performance, with an emphasis on phosphate （P） release behaviors, using both operational data and simulation results. The inverted system exhibited better long-term phosphorus removal performance （0.2 ± 0.3 vs. 0.7 ±0.7 mg/L）, which should be attributed to the higher P release rate （0.79 vs. 0.60 kg P/（kg MLSS.day）） in the non-aerated compartments. The P release occurred in both the anoxic and anaerobic compartments of the inverted system, resulting in more efficient P release. Although the abundances of the ＇Candidatus Accumulibacter phosphatis＇ population in the two systems were quite similar （（19.1 ＋ 3.27）% and （18.4 ＋ 4.15）% of the total microbe （DAPI stained particles） population in the inverted and conventional systems, respectively, by fluorescence in situ hybridization （FISH））, the high-concentration DAPI staining results show that the abundances of the whole polyphosphate accumulating organisms （PAOs） in the aerobic ends were quite different （the average ratios of the poly-P granules to total microbes （DAPI stained particles） were （45 ±4.18）% and （35 ± 5.39）%, respectively）. Both the operational data and simulation results showed that the inverted system retained more abundant PAO populations due to its special configuration, which permitted efficient P release in the non-aerated compartment and better P removal,
基金Project (2009ZX07315-002-01) supported by Water Pollution Control and Management of Major Special Science and Technology
文摘Full scale experimental study on nitrogen removal for low-carbon wastewater was conducted in reversed A2/O process in Jiguanshi waste water treatment plant in Chongqing,in order to aid the operation and maintenance of similar WWTP. When the proposed measures,such as using 0.1% (volume fraction of wastewater) landfill leachate,shortening HRT by 2/3 in the primary sedimentation tank and controlling DO at 0.5 mg/L in the 3rd section of aerobic zone,are applied,15% of the carbon source can be complemented,the favorable property of activated sludge is achieved,and the nitrogen removal effect is significantly improved. The effluent NH3-N is 2 mg/L and the removal rate is 90%. The effluent TN is 17 mg/L and the removal rate is 54%. The up-to-standard discharge of the effluent is achieved. And after the optimization,the unit electricity consumption also reaches 0.21 kW/h and saves 20%.
基金supported by Jilin Provincial Department of Education Science and Technology Project(No.JJKH20230152KJ)the Doctoral Research Initiation Fund(No.BSJXM-2022215).
文摘Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal.
