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Denitrifying Bacteria Isolated from River Sediment and Its Nitrogen and Phosphorus Removal Capacity from River Water
河流沉积物中反硝化细菌的分离及脱氮除磷研究

WANG Lin,LI Ji,KANG Wen-li,CHEN Yun-zeng,GUO Ting-zhong,
王琳
,李季,康文力,陈云增,郭廷忠

环境科学 , 2009,
Abstract: 20 strains of bacteria were isolated from river sediment using enrichment culture medium for denitrification,and the denitrification intensity was determined.F10,one of bacteria strain,was identified having the highest denitrifying intensity,and further used to test its role in the removing of nitrogen and phosphorus from wastewater in laboratory.By checking the individual morphology,colony culture characteristics,DNA sequencing and(16S rDNA) gene bank,F10 was identified as Alcaligenes faecalis,and its deni...
Estimate of denitrifying microbiota in tertiary sewage treatment and kinetics of the denitrification process using different sources of carbon
Marchetto, Margarida;Gianotti, Eloisa Pozzi;Campos, José Roberto;Pires, Roberto Cleto;Moraes, Elizabeth de Mattos;
Brazilian Journal of Microbiology , 2003, DOI: 10.1590/S1517-83822003000200003
Abstract: a study of the kinetics of denitrification was carried out in the laboratory based on the quantification of n2o, the final product of the activity of denitrifying microorganisms, when the enzymatic reduction of n2o to n2 was blocked by acetylene. concentrated mixed liquor (sludge from a reactor with intermittent aeration used for sewage treatment) was used as the inoculum, while methanol, acetic acid, glucose, effluent sewage from an anaerobic fluidized bed reactor and synthetic substrate simulating domestic sewage were used as carbon sources. the mean concentration of nitrate was 20 mg/l. maxima of n2o production and no3- consumption occurred between 0.5h and 2.0h of incubation using all the carbon sources, which characterized the denitrification process. acetic acid and methanol were responsible for the highest rates of n2o production. the estimated number of denitrifying microorganisms in the reactor with intermittent aeration, using the mpn technique, varied from 109 to 1010 mpn/g vss, indicating a high potential for the occurrence of denitrification.
Estimate of denitrifying microbiota in tertiary sewage treatment and kinetics of the denitrification process using different sources of carbon  [cached]
Marchetto Margarida,Gianotti Eloisa Pozzi,Campos José Roberto,Pires Roberto Cleto
Brazilian Journal of Microbiology , 2003,
Abstract: A study of the kinetics of denitrification was carried out in the laboratory based on the quantification of N2O, the final product of the activity of denitrifying microorganisms, when the enzymatic reduction of N2O to N2 was blocked by acetylene. Concentrated mixed liquor (sludge from a reactor with intermittent aeration used for sewage treatment) was used as the inoculum, while methanol, acetic acid, glucose, effluent sewage from an anaerobic fluidized bed reactor and synthetic substrate simulating domestic sewage were used as carbon sources. The mean concentration of nitrate was 20 mg/L. Maxima of N2O production and NO3- consumption occurred between 0.5h and 2.0h of incubation using all the carbon sources, which characterized the denitrification process. Acetic acid and methanol were responsible for the highest rates of N2O production. The estimated number of denitrifying microorganisms in the reactor with intermittent aeration, using the MPN technique, varied from 10(9) to 10(10) MPN/g VSS, indicating a high potential for the occurrence of denitrification.
Denitrification characteristics of a marine origin psychrophilic aerobic denitrifying bacterium

Haiyan Zheng,Ying Liu,Guangdong Sun,Xiyan Gao,Qingling Zhang,Zhipei Liu,

环境科学学报(英文版) , 2011,
Abstract: A psychrophilic aerobic denitrifying bacterium,strain S1-1,was isolated from a biological aerated filter conducted for treatment of recirculating water in a marine aquaculture system.Strain S1-1 was preliminarily identified as Psychrobacter sp.based on the analysis of its 16S rRNA gene sequence,which showed 100% sequence similarity to that of Psychrobacter sp.TSBY-70.Strain S1-1 grew well either in high nitrate or high nitrite conditions with a removal of 100% nitrate or 63.50% nitrite,and the total nitroge...
Preliminary Study on Denitrification Capacity of Constructed Wetlands Filled by Bark
树皮填料补充碳源人工湿地脱氮初步试验研究

JIANG Ying-he,LI Chao,
姜应和
,李超

环境科学 , 2011,
Abstract: Constructed wetlands have been widely used for the treatment of outlets of municipal wastewater treatment plants,treatment of agricultural pollution etc,adequate carbon is a very good source for denitrification and it is very crucial for improving the removal rate of nitrate nitrogen in constructed wetlands.An attempt has been made to workout for the nitrate removal by the integrated vertical constructed wetland,the bark was used for carbon source,the results shows the denitrifying bacteria in the construct...
Research of coking wastewater treatment using mixed immobilized nitrobacteria and aerobic denitrifying bacteria
混合固定化硝化菌和好氧反硝化菌处理焦化废水

Cai Changfeng,Liang Lei,
蔡昌凤
,梁磊

环境工程学报 , 2009,
Abstract: The immobilized ball intermixed by straw powder and activated carbon fiber membrane carrier for use as immobilized cell membrane were made for a improvement on the tradtional PVA immobilization process. After the acidification process by anaerobic baffering reactor with pH of about 8.0 for 18 hours, the coking wastewater was denitrified in the aerobic tank by the mixed immobilized nitrobacteria and aerobic denitrifying bacteria. The NH+4-N removal rates of immobilized ball intermixed by straw powder and carbon fiber membrane immobilization cell media were 94.3% and 85% respectively via the aerobic biological treatment with a working volume of 5 L for 12 hours. The NO-3-N and NO-2-N accumulation phenomena in the reactor were not found and simultaneous nitrification denitrification for the coking wastewater was achieved during the whole aerobic denitrification process.
Characteristic Research of Shortcut Denitrification in Synthetic Ammonia Industrial Wastewater Treatment Process
合成氨废水短程反硝化特性研究

LI Yan,LI Ze-bing,MA Jia-xuan,WANG Xiao-yi,ZHAO Bai-hang,LI Jun,
李妍
,李泽兵,马家轩,王晓毅,赵白航,李军

环境科学 , 2012,
Abstract: Active sludge was from a pilot-scale synthetic ammonia industrial wastewater treatment plant with a strengthen anoxic-oxic (A/O) technology. The zero order kinetic model was suit for describing shortcut and complete denitrification process.Experimental results showed that shortcut denitrification could reduce 14.1% carbon source consumption and 55.7% denitrification time, respectively, comparing with complete denitrification. The maximum specific denitrification rate was 0.509 g·(g·d)-1 with an initial NO2--N concentration of 36.82 mg·L-1 and pH 7.5. In the industrial practice, it must be avoided pH higher than 9.0 in anoxic zone for industrial treatment. Replication-selective denitrifying bacteria showed a strong adaptability to methanol and ethanol, but showed maladaptation to other small molecular and easily biodegradable organics, such as glucose and acetic acid.
Research review of denitrifying microorganisms of groundwater to nitrate denitrification
地下水硝酸盐去除中反硝化微生物的研究进展

LI Fa-Dong,ZHANG Yan,LI Jing,
李发东
,张 妍,李 静

中国生态农业学报 , 2013,
Abstract: There has been an increasing global trend in nitrate contamination of groundwater, and especially in China. This has raised concern for increased nitrate-caused methemoglobinemia and cancer. Available technical data and experience have indicated that denitrification was a more acceptable method for nitrate removal than reverse osmosis and ion exchange. This paper systematically reviewed the denitrifying micro-organisms, denitrification mechanisms, carbon sources, and laboratory/field-scale nitrate removal processes for effective denitrification of groundwater. Key problems with previous studies were also pointed out. As the reviewed showed that there were more related laboratory research than field research, information on the characteristics of specific micro-organisms involved in on-site nitrate removal from groundwater was limited. In addition, the utilization ratio of carbon sources was low and nitrate removal rate from groundwater was also slow. Despite the above issues, metabolic pathways of effective denitrifying micro-organisms used in nitrate removal from groundwater were still unclear. Hence the proposed relevant suggestions included: 1) In situ exploitation of denitrifying micro-organisms. Identification of the specific functions and ecological behaviors of micro-organisms via advanced molecular methods and function gene analyses. 2) Selection of the best sources of carbon and metabolic processes of microorganisms during nitrate removal from groundwater. 3) Clarification of the denitrification processes of nitrogen transformation in groundwater. All the above suggestions provided the basis of the theory of nitrite removal from groundwater, making both the theory and practice more reliable combination.
Isolation, Identification and Denitrification Characterization of Thiobacillus denitrificans
脱氮硫杆菌的分离鉴定和反硝化特性研究

CHE Xuan,LUO Guo-zhi,TAN Hong-xin,WU Jia-min,JIANG Yan,QI Ju-long,SUN Da-chuan,
车轩
,罗国芝,谭洪新,吴嘉敏,蒋燕,齐巨龙,孙大川

环境科学 , 2008,
Abstract: In order to investigate the microbial community structures in different membrane bioreactors, total bacterial genomic DNA was extracted from biomass in four MBRs treating different wastewater. The microbial community structures were studied by polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE) and cloning-sequencing. Furthermore, and the sequences were used for homology analysis and then two phylogenetic trees were constructed. Results indicate that each MBR owns its specific ecological community after a long-term of operation. Influent wastewater composition has a significant impact on total bacterial community structures. Population diversity, which is in the bioreactor fed with more complex components wastewater, is higher than those of other MBRs. The Shannon Index are 0.77 and 0.78. Proteobacteria and Bacillus, which contain 8 OUTs and 2 OUTs, are the climax communities in the investigable MBRs. The profiles of ammonia-oxidizing bacterial community in the four reactors are very similar. There may exist several modes of nitrification and denitrification in MBR because sequences revealed that there exist multitude nitrifying organisms, in which Nitrosomonas are the most predominant, and two denitrifying bacterium (uncultured Achromobacter sp. and uncultured denitrifying bacterium)in reactors.
Characteristics and Affecting Factors of Denitrifying Phosphorus Removal in Two-Sludge Sequencing Batch Reactor
双污泥SBR工艺反硝化除磷脱氮特性及影响因素

WANG Ya-yi,PENG Yong-zhen,YIN Fang-fang,LI Jun,ZHANG Yu-kun,
王亚宜
,彭永臻,殷芳芳,李军,张宇坤

环境科学 , 2008,
Abstract: The characteristics of denitrifying phosphorus removal in a lab-scale two-sludge anaerobic-anoxic/nitrification SBR (A2NSBR) system were studied fed with domestic wastewater. The influence of some key operation parameters, like C/P, C/N, and HRT, were examined using parallel tests. pH, dissolved oxygen (DO) and redox potential (ORP) were monitored on line to validate whether they could be used as the control parameters for this denitrifying phosphorus removal process. Results indicated that P removal efficiency showed an increased trend on the whole with the increase of the C/P. When the influent C/P was greater than 19.39, good phosphorus removal efficiency was achieved. However, the phosphorus removal efficiency deteriorated once the influent C/P decreased less than 15.36. On the other hand, relatively good phosphorus removal efficiency could be maintained in the A2NSBR system even at a low C/N ratio, though the denitrification efficiency decrease instead. It is also found that increasing the influent C/N increased the PHB amount stored by polyphosphate accumulating organisms (PAO) and therefore the ultimate denitrification and phosphorus removal efficiency were both improved. For an excessively high C/N, the incompletely reacted COD will be residual to anoxic stage. Thus, the pure denitrification reaction, which preferentially supports OHOs, becomes the dominant reaction. This decreases the amount of available electron acceptors for denitrifying polyphosphate accumulating organisms (DNPAOs) at the anoxic stage which eventually impacts the anoxic phosphorus removal capacity. In addition, since A2NSBR has two completely independent SBR systems, it benefits to establish a process control system in terms of the parameters DO, ORP, and pH.
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