Many nitrogen-containing aromatic compounds （NACs）, such as nitrobenzene （NB）, 4-nitrophenol （4-NP）, aniline （AN）, and 2,4-dinitrophenol （2,4-DNP）, are environmentally hazardous, and their removal from conta...Many nitrogen-containing aromatic compounds （NACs）, such as nitrobenzene （NB）, 4-nitrophenol （4-NP）, aniline （AN）, and 2,4-dinitrophenol （2,4-DNP）, are environmentally hazardous, and their removal from contaminated water is one of the main challenges facing wastewater treatment plants. In this study, synthetic wastewater containing NB, 4-NP, 2,4-DNP, and AN at concentrations ranging from 50 to 180 mg/L was fed into a sequencing batch reactor （SBR）. Analyses of the SBR system indicated that it simultaneously removed more than 99% of the NACs at loading rates of 0.36 kg NB/（m^3·d）, 0.3 kg 4-NP/（m^3·d）, 0.25 kg AN/（m^3·d）, and 0.1 kg 2,4-DNP/（m^3·d）. Bacterial groups of Bacteriodetes, Candidate division TM7, α-Proteobacteria, and β-Proteobacteria were dominant in the clone libraries of 16S rRNA genes retrieved from the microbial communities in the SBR system. ＂Cycle tests＂ designed to alter feeding and aeration parameters of the SBR system demonstrated that the resident microbial biome of the SBR system responded rapidly to changing conditions. Consumption of O2 was concomitant with the apparent mineralization of NACs. Aromatic ring-cleaving dioxygenase activities suggested that （1） AN and NB were degraded via catechol 2,3-dioxygenase; （2） 4-NP was degraded via 1,2,4-benzentriol 1,2-dioxygenase; and （3） 2,4-DNP was degraded via an unresolved pathway.展开更多
Process scale-up remains a considerable challenge for environmental applications of non-thermal plasmas.Undersanding the impact of reactor hydrodynamics in the performance of the process is a key step to overcome this...Process scale-up remains a considerable challenge for environmental applications of non-thermal plasmas.Undersanding the impact of reactor hydrodynamics in the performance of the process is a key step to overcome this challenge.In this work,we apply chemical engineering concepts to analyse the impact that different non-thermal plasma reactor configurations and regimes,such as laminar or plug flow,may have on the reactor performance.We do this in the particular context of the removal of pollutants by non-thermal plasmas,for which a simplified model is available.We generalise this model to different reactor configurations and,under certain hypotheses,we show that a reactor in the laminar regime may have a behaviour significantly different from one in the plug flow regime,often assumed in the non-thermal plasma literature.On the other hand,we show that a packed-bed reactor behaves very similarly to one in the plug flow regime.Beyond those results,the reader will find in this work a quick introduction to chemical reaction engineering concepts.展开更多
Based on the method of compound and additional conditions under the conditions of the equal temperature rise and the equal potential drop (P.D.) of resistance, the application of design software of dry-type air-core r...Based on the method of compound and additional conditions under the conditions of the equal temperature rise and the equal potential drop (P.D.) of resistance, the application of design software of dry-type air-core reactor is introduced in this thesis. The analytical methods of the inductance are also given. This approach is proved entirely feasible in theory through the simplification with Bartky transformation, and is able to quickly and accurately calculate reactor inductance. This paper presents the analytical methods of the loss of dry-type air-core reactor as well.展开更多
基金Project supported by the Pilot Project of Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-G-009)the National Natural Science Foundation of China (No. 20577067, 30230010).
文摘Many nitrogen-containing aromatic compounds （NACs）, such as nitrobenzene （NB）, 4-nitrophenol （4-NP）, aniline （AN）, and 2,4-dinitrophenol （2,4-DNP）, are environmentally hazardous, and their removal from contaminated water is one of the main challenges facing wastewater treatment plants. In this study, synthetic wastewater containing NB, 4-NP, 2,4-DNP, and AN at concentrations ranging from 50 to 180 mg/L was fed into a sequencing batch reactor （SBR）. Analyses of the SBR system indicated that it simultaneously removed more than 99% of the NACs at loading rates of 0.36 kg NB/（m^3·d）, 0.3 kg 4-NP/（m^3·d）, 0.25 kg AN/（m^3·d）, and 0.1 kg 2,4-DNP/（m^3·d）. Bacterial groups of Bacteriodetes, Candidate division TM7, α-Proteobacteria, and β-Proteobacteria were dominant in the clone libraries of 16S rRNA genes retrieved from the microbial communities in the SBR system. ＂Cycle tests＂ designed to alter feeding and aeration parameters of the SBR system demonstrated that the resident microbial biome of the SBR system responded rapidly to changing conditions. Consumption of O2 was concomitant with the apparent mineralization of NACs. Aromatic ring-cleaving dioxygenase activities suggested that （1） AN and NB were degraded via catechol 2,3-dioxygenase; （2） 4-NP was degraded via 1,2,4-benzentriol 1,2-dioxygenase; and （3） 2,4-DNP was degraded via an unresolved pathway.
文摘Process scale-up remains a considerable challenge for environmental applications of non-thermal plasmas.Undersanding the impact of reactor hydrodynamics in the performance of the process is a key step to overcome this challenge.In this work,we apply chemical engineering concepts to analyse the impact that different non-thermal plasma reactor configurations and regimes,such as laminar or plug flow,may have on the reactor performance.We do this in the particular context of the removal of pollutants by non-thermal plasmas,for which a simplified model is available.We generalise this model to different reactor configurations and,under certain hypotheses,we show that a reactor in the laminar regime may have a behaviour significantly different from one in the plug flow regime,often assumed in the non-thermal plasma literature.On the other hand,we show that a packed-bed reactor behaves very similarly to one in the plug flow regime.Beyond those results,the reader will find in this work a quick introduction to chemical reaction engineering concepts.
文摘Based on the method of compound and additional conditions under the conditions of the equal temperature rise and the equal potential drop (P.D.) of resistance, the application of design software of dry-type air-core reactor is introduced in this thesis. The analytical methods of the inductance are also given. This approach is proved entirely feasible in theory through the simplification with Bartky transformation, and is able to quickly and accurately calculate reactor inductance. This paper presents the analytical methods of the loss of dry-type air-core reactor as well.
