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A study on removing nitrogen from highly nitrogenous MG wastewater with process of shortened nitrification/denitrification
高氨氮味精废水的亚硝化/反亚硝化脱氮研究

FANG Shi,LI Xiaohuan,
方士
,李筱焕

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.
Inhibition of nitrification in soil by metal diethyldithiocarbamates
AArora,Bijay Singh,Dhiraj Sud,TSrivastava,CLArora,
A. Aror
,Bijay Singh,Dhiraj Su,T.Srivastav,C. L. Arora

环境科学学报(英文版) , 2003,
Abstract: Nitrification acts as a key process in determining fertilizer use efficiency by crops as well as nitrogen losses from soils. Metal dithiocarbamates in addition to their pesticidal properties can also inhibit biological oxidation of ammonium(nitrification) in soil. Metal M = V(III), Cr(III), Mn(II), Fe(III), Ni(II), Cu(II), Zn(II) and Co(II)] diethyldithiocarbamates (DEDTC) were synthesized by the reaction of sodium diethyldithiocarbamate with metal chloride in dichloromethane/water mixture. These metal diethyldithiocarbamates were screened for their ability to inhibit nitrification at different concentrations( 10 microg/g soil, 50 microg/g soil and 100 microg/g soil). With increasing concentration of the complex, capacity to retard nitrification increased but the extent of increase varied for different metals. At 100 microg/g soil, different complexes showed nitrification inhibition from 22.36% to 46.45% . Among the diethyldithiocarbamates tested, Zn(DEDTC)2 proved to be the most effective nitrification inhibitor at 100 microg/g soil. Manganese, iron and chromium diethyldithiocarbamates also proved to be effective nitrification inhibitors than the others at 100 microg/g soil. The order of percent nitrification inhibition in soil by metal diethyldithiocarbamates was: Zn(II) > Mn(II) > Fe(III) > Cr(III) > V(III) > Co(II) > Ni(II) > Cu(II).
Nitrification Inhibition in Soil and Ecosystem Functioning An Overview
F. Azam,S. Farooq
Pakistan Journal of Biological Sciences , 2003,
Abstract: Form (NH4 or NO3) and availability of N has significant implications to the functioning and sustainability of agroecosystems. Most of the fertilizer nitrogen (N) applied to agricultural soils is in the form of NH4 or NH4-forming fertilizers. This form of N is rapidly oxidized to NO3 by nitrifying microorganisms leading to significant losses of N through NO3-leaching and denitrification. Both denitrification and NO3-leaching have environmental implications and economic concerns. Strategies have therefore been sought to regulate the process of nitrification leading to its complete or partial inhibition. Indeed, climax ecosystems are developed in such a way that the process of nitrification is already fairly inhibited. This paper presents an overview on: I) the process of nitrification, ii) microorganisms involved, iii) the implications of nitrification and nitrification inhibition to ecosystem functioning and finally iv) the methods to inhibit nitrification.
Nitrogen removal from the sewage containing seawater via nitrite pathway
含海水污水的短程硝化反硝化

Yu Deshuang,Peng Yongzhen,Song Xueqi,Li Mei,
Yu D
,Peng Y,Song X,Li M

环境科学 , 2003,
Abstract: With control of the concentration of free ammonia (FA), shortened nitrification-denitrification was accomplished in SBR to achieve enhanced nitrogen removal from the sewage containing seawater. Several parameters which included salinity, temperature, pH and NH4(+)-N load were studied to evaluate their effects. The results of experiences indicated that shortened nitrification-denitrification can be accomplished in sewage containing seawater with relatively high salinity. With various salinity, the nitrogen removal efficiency had relationship with the NH4(+)-N load, there should be a lower NH4(+)-N load when the salinity was high. The nitrogen removal efficiency reached above 90% when the NH4(+)-N load was not exceed 0.15 kg/(kg.d). Elevation of the temperature availed to higher nitrogen removal efficiency, this efficiency doubled when the reaction temperature was changed from 20 degrees C to 30 degrees C. Relatively high value of pH, in the range of 7.5 and 8.5 had advantage to achieve effective shortened nitrification-denitrification which caused by the selective inhibition of free ammonia(FA).
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.
Variation of functional bacteria during start-up and operation of partial nitrification process
短程硝化启动运行中功能菌群变化研究

CHEN Xiao-Xuan,LIU Chun,YANG Jing-Liang,ZHANG Run,YANG Hui-Na,
陈晓轩
,刘春,杨景亮,张润,杨辉娜

微生物学通报 , 2012,
Abstract: Objective] Partial nitrification-anammox is considered as the shortest?process for biological nitrogen removal and partial nitrification is the important part of this process. Methods] The variation of functional bacteria during start-up and stable operation of partial nitrification process was investigated in a SBR bioreactor in this study. Results] The results indicated that ammonia-oxidizing bacteria (AOB) population was expanded significantly and nitrite-oxidizing bacteria (NOB) population was inhibited when DO concentration was controlled lower than 1 mg/L and ammonia loading of the influent increased gradually. As a result, start-up and stable operation of partial nitrification process was realized. When ammonia volumetric loading of the influent was 0.055 kg/(m3·d), the average ammonia removal volumetric loading and sludge loading were 0.043 kg/(m3·d) and 0.16?kg/(kg·d), respectively. In addition, the average nitrite accumulation rate was 83.4% at this time. AOB population density and relative abundance increased from 4.5×104 CFU/mL to 1.5×107CFU/mL and from 0.18% to 7.25%, respectively, during start-up and stable operation of partial nitrification process. At the same time, NOB population density and relative abundance decreased from 2.0×105 CFU/mL to 1.5×104 CFU/mL?and from 5.51% to 2.14%, respectively. Conclusion] The expansion of AOB population was responsible for realization of partial nitrification and ammonia removal. High ammonia concentration and loading?also caused the activity inhibition of partial nitrification.
Role of pH on biological Nitrification Process  [PDF]
Iswar Man Amatya,Bhagwan Ratna Kansakar,Vinod Tare,Liv Fiksdal
Journal of the Institute of Engineering , 2011, DOI: 10.3126/jie.v8i1-2.5102
Abstract: It is important to determine the effect of changing environmental conditions on the microbial kinetics for design and modeling of biological treatment processes. In this research, the kinetics of ammonia oxidation by nitrifying process bacteria under varying pH and temperature conditions are studied. Ammonia oxidation in groundwater was carried out by biological method of nitrification process. The nitrification was performed in one set of reactors. The reactor consists of two columns connected in series packed with over burnt bricks as media. The filtration rate varied from 10.5 to 210.4 m/day for nitrification process respectively. The ammonia, nitrate and nitrite nitrogen concentrations were measured at inlet, intermediate ports and outlet. The temperature varied from 10 to 30°C at 2°C intervals. The results demonstrated that high amounts of ammonia nitrogen nitrified in groundwater at nitrification process. The average ammonia nitrogen oxidation efficiency of 77.27% was achieved from pH 7.3 to 8.0 in the reactor packed with OBB media at 20°C, for the flow rate 500ml/min due to biological nitrification. The total amount of ammonia nitrogen removed by nitrification varied from 0.76 to 17.80 gm/m 3 /h at influent concentration from 2.84 to 149.28 gm/m 3 /h. Key words: Over burnt brick; Filtration rate; Temperature; Nitrification and Nitrifying bacteria DOI: http://dx.doi.org/10.3126/jie.v8i1-2.5102 Journal of the Institute of Engineering Vol. 8, No. 1&2, 2010/2011 Page: 119-125 Uploaded Date : 20 July, 2011
Oxygen-limited autotrophic nitrification and denitrification- A novel technology for biological nitrogen removal
限氧自养硝化—反硝化生物脱氮新技术

ZHANG Dan,XU Hui,LI Xiangli,ZHANG Ying,CHEN Guanxiong,
张丹
,徐慧,李相力,张颖,陈冠雄

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.
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.
Study on Characteristics in the Removal Process of Ammonia Nitrogen and Nitrate Nitrogen by an Isolated Heterotrophic Nitrification-Aerobic Denitrification Strain Rhodococcus Sp.  [PDF]
Weisi Li
Journal of Environmental Protection (JEP) , 2013, DOI: 10.4236/jep.2013.41B014
Abstract: Removal of ammonia nitrogen and nitrate nitrogen by an heterotrophic nitrification-aerobic denitrification strain is an economical and effective method. In this article, a kind of heterotrophic nitrification-aerobic denitrification strain which has aerobic denitrification and heterotrophic nitrification ability was selected, and then was identified as rhodococcus sp. by 16S rRNA sequencing analysis and morphological observation. After that, carbon source utilization and nitrification- denitrification activity of this strain in different C/N, initial nitrogen concentration were studied. In addition, the assimilation and denitrification activities of ammonia and nitrate were also researched under the condition of nitrate and ammonia coexisted in the solution. The results show that the strain can grow in sodium acetate, glucose, sodium succinate and sodium citrate solutions, and it can not survive in sodium oxalate, sucrose and soluble starch solutions. Initial concentration and C/N were important for nitrogen removal rate. This strain can completely remove nitrate/ammonia when nitrate/ammonia concentration was lower than 15 mg l-1/80 mg l-1. the C/N of 10 and of 12 were the optimum C/N ratio in the nitrate and ammonia removal process respectively. pH value rose up sharply in the denitrification process and it increased relatively slowly in the nitrification process, which shows that pH is one of the most important factor inhibiting the denitrification removal process. Nitrite concentration was much higher in denitrification process than in nitrification process. In addition, this strain gave priority to utilizing ammonia as nitrogen source when ammonia and nitrate coexisted in the solution.
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