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Advances in Denitrification Characteristics of Heterotrophic Nitrification Bacteria


微生物学通报 , 2009,
Abstract: Heterotrophic nitrification bacteria are able to utilize organic carbon sources to grow and produce hydroxylamine, nitrite and nitrate from nitrogen compounds, and most of them can also denitrify these products to gaseous nitrogen compounds simultaneously. Therefore, more and more attentions are paid to heterotrophic nitrification bacteria for wastewater treatment. This paper reviews the denitrification characteristics of some isolated heterotrophic nitrification bacteria, and analyzes the influence of various conditions to the heterotrophic nitrification bacteria, such as temperature, pH, DO, carbon sources, C/N, and inhibitors, etc. At last, the present situation and potential applications of wastewater treatment by heterotrophic nitrification bacteria are introduced.
Screening and Denitrification Characteristics of a Heterotrophic Nitrification-Aerobic Denitrifier Bacteria

CHEN Pei-zhen,WANG Li-gang,WANG Ying-chun,LI Ji,DING Wei,REN Tian-zhi,LI Shao-peng,

环境科学 , 2009,
Abstract: A heterotrophic nitrification-aerobic denitrifier bacteria CPZ24 was isolated form the livestock wastewater by way of the limiting dilution combined with the chromogenic medium screening methods. This bacterium was Gram positive, rod. The colonies of the strain were orange-red.It was identified as Rhodococuus pyridinivorans according to its morphological and physiological properties and the analysis of its 16S rDNA gene. Studied on its function of heterotrophic nitrification and aerobic denitrification,the results show that all NH+4-N is removed and the removal rate of TN is 98.70% in heterotrophic nitrification; the removal rate of NO-3-N by this strain is 66.74% and the removal rate of TN is 64.27%.This high effective microorganisms with nitrogen removed is able to realize simultaneous nitrification and denitrification.It can perform the whole process of bacteria denitrification independently.
Heterotrophic nitrification, anaerobic ammonia oxidation and archaeal ammonia oxidation in a new nitrogen cycle

环境科学学报 , 2008,
Abstract: The global nitrogen cycle is driven by a series of microbial activities. In the past few years, the understanding of nitrogen cycling processes has changed dramatically based on some new processes, including heterotrophic nitrification, anaerobic ammonium oxidation (Anammox) and archaeal ammonia oxidation. In this review, the discovery, biochemistry mechanism and molecular biology of organisms linked to these processes are presented and relevant unknown questions are highlighted. A new nitrogen cycle will only emerge through considering all of these processes and microbial groups together. In addition, the paper presents some new perspectives about the application of these new organisms in biological nitrogen removal from wastewater. These new perspectives include enriching heterotrophic nitrification bacteria to enhance simultaneous nitrification-denitrification, enriching Anammox to achieve single-stage autotrophic nitrogen removal and enriching ammonia oxidation archaea to improve nitrogen removal efficiency at low dissolved oxygen (DO).
Simultaneous nitrification and denitrification in step feeding biological nitrogen removal process
ZHU Gui-bing,PENG Yong-zhen,WU Shu-yun,WANG Shu-ying,XU Shi-wei,
ZHU Gui-bing
,PENG Yong-zhen,WU Shu-yun,WANG Shu-ying,XU Shi-wei

环境科学学报(英文版) , 2007,
Abstract: The simultaneous nitrification and denitrification in step-feeding biological nitrogen removal process were investigated under different influent substrate concentrations and aeration flow rates.Biological occurrence of simultaneous nitrification and denitrifieation was verified in the aspect of nitrogen mass balance and alkalinity.The experimental results also showed that there was a distinct linear relationship between simultaneous nitrification and denitrification and DO concentration under the conditions of low and high aeration flow rate.In each experimental run the floe sizes of activated sludge were also measured and the results showed that simultaneous nitrification and denitrification could occur with very small size of floc.
Simultaneous nitrification and denitrification of high ammonia nitrogen wastewater

Li Jiuyi,Wu Nianpeng,Liu Ying,Li Jin,

环境工程学报 , 2007,
Abstract: The effects of dissolved oxygen concentration and influent carbon to nitrogen ratio on nitrogen removal performance of a wastewater containing strength ammonia nitrogen were investigated in a sequencing batch reactor. Experimental results showed that the decrease of dissolved oxygen concentration led to short-cut simultaneous nitrification and denitrification and improved the total-nitrogen removal capacity. External carbon source uptake, PHB storage, aerobic PHB oxidation and simultaneous nitrification-denitrification processes were taken place in the operation of the reactor. PHB was demonstrated to be the electron donor of denitrification reaction in the simultaneous nitrification-denitrification process.
Removal of organic matter and nitrogen from distillery wastewater by a combination of methane fermentation and denitrification/nitrification processes
LI Jun,ZHANG Zhen-ji,LI Zhi-rong,HUANG Guang-yu,Naoki Abe,
LI Jun
,ZHANG Zhen-ji,LI Zhi-rong,HUANG Guang-yu,Naoki Abe

环境科学学报(英文版) , 2006,
Abstract: The distillery wastewater of Guangdong Jiujiang Distillery, which is characteristic of containing high organic matters and rich total nitrogen, was treated by a combination of methane fermentation and denitrification/nitrification processes. 80% of COD in the raw wastewater was removed by methane fermentation at the COD volumetric loading rate of 20 kg COD/(m3 x d) using the expanded granule sludge bed (EGSB) process. However, almost all the organic nitrogen in the raw wastewater was converted into ammonia by ammonification there. Ammonia and volatile fatty acids (VFA) remaining in the anaerobically treated wastewater were simultaneously removed utilizing VFA as an electron donor by denitrification occurring in the other EGSB reactor and nitrification using PEG-immobilized nitrifying bacteria with recirculation process. An aerobic biological contact oxidization reactor was designed between denitrification/nitrification reactor for further COD removal. With the above treatment system, 18000-28000 mg/L of COD in raw wastewater was reduced to less than 100 mg/L. Also, ammonia in the effluent of the system was not detected and the system had a high removal rate for 900-1200 mg/L of TN in the raw wastewater, only leaving 400 mg/L of nitrate nitrogen.
The characteristics of nitrogen fixation, ammonification, nitrification and denitrification in coastal zones

XU Jirong,WANG Youshao,SUN Song,

生态学报 , 2004,
Abstract: The biogeochemical cycling of nitrogen is a significant factor influencing global climatic change. It is a complex process involving interactions between the atmosphere, seawater, sediments, and microorganisms. Nitrogen cycling is particularly active in estuarine and coastal zones, regions where human activities can impact on the natural process. There are four major processes in biogeochemical cycling: nitrification fixation;organic nitrogen ammonification;nitrification, and denitrification. The mechanism...
A study on removing nitrogen from highly nitrogenous MG wastewater with process of shortened nitrification/denitrification

FANG Shi,LI Xiaohuan,

环境科学学报 , 2001,
Abstract: The dilute N rich monosodium glutamate(MG)wastewater was treated by two stage SBR process.The process can be divided into carbon oxidation stage and three shortened nitrification/denitrification stages.The pathway of nitrogen removal from N rich MG wastewater was proved to be via stripping with carbon oxidation stage and shortened nitrification/denitrification subsequently.In the carbon oxidation stage,DO was consumed by high concentrations of organic compound so that nitrification was repressed,Inhibition of nitrite oxidation by free ammonia(FA)resulted in the formation of shortened nitrification/denitrification process.
Nitrogen removal influence factors in A/O process and decision trees for nitrification/denitrification system
MA Yong,PENG Yong-zhen,WANG Shu-ying,WANG Xiao-Lian,
MA Yong
,PENG Yong-zhen,WANG Shu-ying,WANG Xiao-lian

环境科学学报(英文版) , 2004,
Abstract: In order to improve nitrogen removal in anoxic/oxic(A/O) process effectively for treating domestic wastewaters, the influence factors, DO(dissolved oxygen), nitrate recirculation, sludge recycle, SRT(solids residence time), influent COD/TN and HRT(hydraulic retention time) were studied. Results indicated that it was possible to increase nitrogen removal by using corresponding control strategies, such as, adjusting the DO set point according to effluent ammonia concentration; manipulating nitrate recirculation flow according to nitrate concentration at the end of anoxic zone. Based on the experiments results, a knowledge-based approach for supervision of the nitrogen removal problems was considered, and decision trees for diagnosing nitrification and denitrification problems were built and successfully applied to A/O process.
Organic matter and concentrated nitrogen removal by shortcut nitrification and denitrification from mature municipal landfill leachate
ZHANG Shu-jun,PENG Yong-zhen,WANG Shu-ying,ZHENG Shu-wen,GUO Jin,
ZHANG Shu-jun
,PENG Yong-zhen,WANG Shu-ying,ZHENG Shu-wen,GUO Jin

环境科学学报(英文版) , 2007,
Abstract: An UASB Anoxic/Oxic (A/O) system was introduced to treat a mature landfill leachate with low carbon-to-nitrogen ratio and high ammonia concentration. To make the best use of the biodegradable COD in the leachate, the denitrification of NOx-N in the recirculation effluent from the clarifier was carried out in the UASB. The results showed that most biodegradable organic matters were removed by the denitrification in the UASB. The NH4 -N loading rate (ALR) of A/O reactor and operational temperature was 0.28-0.60 kg NH4 -N/(m3·d) and 17-29℃ during experimental period, respectively. The short-cut nitrification with nitrite accumulation efficiency of 90%-99% was stabilized during the whole experiment. The NH4 -N removal efficiency varied between 90% and 100%. When ALR was less than 0.45 kg NH4 -N/(m3·d), the NH4 -N removal efficiency was more than 98%. With the influent NH4 -N of 1200-1800 mg/L, the effluent NH4 -N was less than 15 mg/L. The shortcut nitrification and denitrification can save 40% carbon source, with a highly efficient denitrification taking place in the UASB. When the ratio of the feed COD to feed NH4 -N was only 2-3, the total inorganic nitrogen (TIN) removal efficiency attained 67%-80%. Besides, the sludge samples from A/O reactor were analyzed using FISH. The FISH analysis revealed that ammonia oxidation bacteria (AOB) accounted for 4% of the total eubacterial population, whereas nitrite oxidation bacteria (NOB) accounted only for 0.2% of the total eubacterial population.
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