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The effect of temperature on short-cut nitrification and denitrification

SHANG Huilai,PENG Yongzhen,ZHANG Jingrong,WANG Shuying,

环境科学学报 , 2009,
Abstract: The effect of temperature on the stabilization of short-cut nitrification and denitrification together with the rates of nitrification and denitrification were studied in a Sequencing Batch Reactor(SBR) treating domestic wastewater.The experimental results demonstrated that real-time control and controlling sludge retention time(SRT=10d) could realize short-cut nitrification and denitrification.Experiments were carried out by decreasing the temperature of the system whenever the nitrite accumulation reached...
Stability of Shortcut Nitrification-Denitrification

GAO Da-wen,PENG Yong-zhen,WANG Shu-ying,

环境科学 , 2005,
Abstract: The effects of temperature and aeration time on the stability of shortcut nitrification-denitrification are studied specially in some experiments are carried on a sequencing batch reactor (SBR) fed with soybean wastewater. Results show that shortcut nitrification-denitrification achieved by controlling temperature was not stable until the temperature was more than 28 degrees C. In addition, for the first time strong effect of excess aeration on shortcut nitrification-denitrification is observed. When the system run under excess aeration for twelve days, the type of nitrification turned from shortcut nitrification which nitrosation rate (NO2(-)-N/NOx(-) -N) was more than 96% to complete nitrification which nitrosation rate (NO2(-) -N/NOx(-) -N) was less than 39.3%. So, in order to make shortcut nitrification-denitrification run stably, real-time process control must be used.
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.
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.
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.
Influence of Distillery Slop on Methane Emission in Rice Paddies  [PDF]
Tasanee Thitakamol
EnvironmentAsia , 2008,
Abstract: Methane is a green house gas causing global warming. It is produced naturally during bio-fermentation under suitable anaerobic condition. When rice is grown in the tropics, there is some emission of methane. We studied the emission of methane during rice production in Thailand, in particular the effect of using of distillery slop on the rice fields. Release of methane was measured once a week for 18 weeks from plots using 4 different doses of distillery slop: 0, 125, 250 and 375 m3/hectare, and 3 doses of chemical fertilizer: 0, 94 and 188 kg/hectare. The use of distillery slop did not significantly influence methane emission in the rice fields during any period of rice production. Furthermore, the measured quantities of methane were considerably lower than other sources of methane emission.
Temperature effect on aerobic denitrification and nitrification
XIE Shu-guang,ZHANG Xiao-jian,WANG Zhan-sheng,
XIE Shu-guang
,ZHANG Xiao-jian,WANG Zhan-sheng

环境科学学报(英文版) , 2003,
Abstract: Nitrogen loss without organic removal in biofilter was observed and its possible reason was explained. A lower hydraulic loading could improve aerobic denitrification rate. Aerobic denitrification was seriously affected by low temperature(below 10 degrees C). However, nitrification rate remained high when the temperature dropped from 15 degrees C to 5 degrees C . It seemed the autotrophic biofilm in BAF could alleviate the adverse effect of low temperature.
Removing Nitrogen from Low-C/N-Piggery-Wastewater Using Shortcut Nitrification/denitrification-ANAMMOX

WANG Huan,PEI Wei-zheng,LI Xu-dong,HAO Chun,ZENG Kang-mei,

环境科学 , 2009,
Abstract: Aiming at the problem of deficiency of organic carbon source in piggery wastewater treatment by traditional method,shortcut nitrification/denitrification-ANAMMOX was used to remove nitrogen in piggery wastewater with low C/N in SBBR reactors.The results showed that shortcut nitrification/denitrification provided good influent conditions for ANAMMOX.High nitrogen removal efficiency of piggery wastewater by ANAMMOX was achieved and the average removal percentage of ammonium,nitrite and total nitrogen reached ...
Oxygen-limited autotrophic nitrification and denitrification- A novel technology for biological nitrogen removal

ZHANG Dan,XU Hui,LI Xiangli,ZHANG Ying,CHEN Guanxiong,

应用生态学报 , 2003,
Abstract: Oxygen-limited autotrophic nitrification and denitrification (OLAND) is a biological nitrogen removal process coupled with partial nitrification and anaerobic ammonium oxidation. In our study, the nitrification was blocked at nitrite stage by controlling the dissolved oxygen concentration at 0.1-0.3 mg.L-1, and then, the denitrification proceeded, with the residual ammonium at the partial nitrification stage as electron donor. As a completely autotrophic nitrification-denitrification process, the OLAND was of many advantages (e.g., low energy consumption, high nitrogen removal rate and small footprint of system), and suitable in particular for treating low COD/NH4(+)-N ratio wastewater. It has become one of the most prosperous and practicable biological nitrogen removal technologies. The recent research of OLAND was reviewed, and its microbial mechanism as well as its applicable prospect was remarked in this paper.
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.
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