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Nitrification and growth of autotrophic nitrifying bacteria and Thaumarchaeota in the coastal North Sea
B. Veuger, A. Pitcher, S. Schouten, J. S. Sinninghe Damsté,J. J. Middelburg
Biogeosciences (BG) & Discussions (BGD) , 2013,
Abstract: Nitrification and the associated growth of autotrophic nitrifiers, as well as the contributions of bacteria and Thaumarchaeota to total autotrophic C-fixation by nitrifiers were investigated in the Dutch coastal North Sea from October 2007 to March 2008. Rates of nitrification were determined by incubation of water samples with 15N-ammonium and growth of autotrophic nitrifiers was measured by incubation with 13C-DIC (dissolved inorganic carbon) in the presence and absence of nitrification inhibitors (nitrapyrin and chlorate) in combination with compound-specific stable isotope (13C) analysis of bacterial and Thaumarchaeotal lipid biomarkers. Net nitrification during the sampling period was evident from the concentration dynamics of ammonium, nitrite and nitrate. Measured nitrification rates were high (41–221 nmol N L 1 h 1). Ammonium assimilation was always substantially lower than nitrification – with nitrification on average contributing 89% (range 73–97%) to total ammonium consumption. 13C-DIC fixation into bacterial and Thaumarchaeotal lipids was strongly reduced by the nitrification inhibitors (27–95 %). The inhibitor-sensitive 13C-PLFA (phospholipid-derived fatty acid) pool was dominated by the common PLFAs 16:0, 16:1ω7c and 18:1ω7c throughout the whole sampling period and occasionally also included the polyunsaturated fatty acids 18:2ω6c and 18:3ω3. 13C-DIC fixation activity of the nitrifying bacteria was much higher than that of the nitrifying Thaumarchaeota throughout the whole sampling period, even during the peak in Thaumarchaeotal abundance and activity. This suggests that the contribution of autotrophic Thaumarchaeota to nitrification during winter in the coastal North Sea may have been smaller than expected from their gene abundance (16S rRNA and amoA (ammonia monooxygenase)). These results emphasize the importance of direct measurements of the actual activity of bacteria and Thaumarchaeota, rather than abundance measurements only, in order to elucidate their biogeochemical importance. The ratio between rates of nitrification versus DIC fixation by bacterial nitrifiers was higher or even much higher than typical values for autotrophic nitrifiers, indicating that little DIC was fixed relative to the amount of energy that was generated by nitrification.
Nitrification and growth of autotrophic nitrifying bacteria and Thaumarchaeota in the coastal North Sea
B. Veuger,A. Pitcher,S. Schouten,J. S. Sinninghe Damsté
Biogeosciences Discussions , 2012, DOI: 10.5194/bgd-9-16877-2012
Abstract: Nitrification and the associated growth of autotrophic nitrifiers, as well as the contributions of bacteria and Thaumarchaeota to total autotrophic C-fixation by nitrifiers were investigated in the Dutch coastal North Sea from October 2007 to March 2008. Rates of nitrification were determined by incubation of water samples with 15N-ammonium and growth of autotrophic nitrifiers was measured by incubation with 13C-DIC in the presence and absence of nitrification inhibitors (nitrapyrin and chlorate) in combination with compound-specific stable isotope (13C) analysis of bacterial- and Thaumarchaeotal lipid biomarkers. Net nitrification during the sampling period was evident from the concentration dynamics of ammonium, nitrite and nitrate. Measured nitrification rates were high (41–221 nmol N l 1h 1). Ammonium assimilation was always substantially lower than nitrification with nitrification on average contributing 89% (range 73–97%) to total ammonium consumption. 13C-DIC fixation into bacterial and Thaumarchaeotal lipids was strongly reduced by the nitrification inhibitors (27–95%). The inhibitor-sensitive 13C-PLFA pool was dominated by the common PLFAs 16:0, 16:1ω7c and 18:1ω7c throughout the whole sampling period and occasionally also included the polyunsaturated fatty acids 18:2ω6c and 18:3ω3. Cell-specific 13C-DIC fixation activity of the nitrifying bacteria was much higher than that of the nitrifying Thaumarchaeota throughout the whole sampling period, even during the peak in Thaumarchaeotal abundance and activity. This suggests that the contribution of autotrophic Thaumarchaeota to nitrification during winter in the coastal North Sea may have been smaller than expected from their gene abundance. These results emphasize the importance of direct measurements of the actual activity of bacteria and Thaumarchaeota, rather than abundance measurements only, in order to elucidate their biogeochemical importance. The ratio between rates of nitrification versus DIC fixation by nitrifiers was higher or even much higher than typical values for autotrophic nitrifiers, indicating that little DIC was fixed relative to the amount of energy that was generated by nitrification.
Nitrification Potential Removal in an Autotrophic Membrane Bioreactor  [PDF]
Aicha G.,Marc H.,Alain H. A. G.
International Journal of Chemical and Environmental Engineering , 2012,
Abstract: Membrane bioreactor (MBR) process has now become an attractive option for the treatment and reuse of industrial and municipal wastewaters, as evidenced by their constantly rising numbers and capacity. However a good water effluent quality hides a very complex biological system involving particulate and soluble components. The efficiency of this system is mainly dependent on the nature of the bacterial communities in the MBR. For many decades the most common factor used to express all parameters needed for describing the biological reaction rate was the volatile suspended solids concentration (VSS). Different reaction rates’ data, expressed in terms of mgN g-1MVS h-1 are reported in literature. However, it is quite obvious that the VSS measurement is not an adequate indicator of the active biomass. Indeed it contains, besides active microorganisms, biodegradable and inert particulate substrate as well as the residue of bacterial death and lyses. This was perhaps the major cause of the reported nitrification rates discrepancies between the researchers. The idea in our study was to find a new way of expressing the nitrification potential through a new standard unit which is mgN gCOD-1biomass h-1. The challenge was then how to find a new and easy method to reach the active biomass in the membrane bioreactor regardless of the operating conditions. Four runs were conducted under different conditions; the identification of active biomass was done using the respirometric tools. The nitrification rates obtained were 14.59, 14.5, 21.25 and 18.16 g N gVSS-1h-1, but when expressed in terms of the active biomass we found approximately the same nitrification rate with values of 0.553, 0.551, 0.587 and 0.557 gN/g COD biomass/h respectively.
An autotrophic nitrogen removal process: Short-cut nitrification combined with ANAMMOX for treating diluted e uent from an UASB reactor fed by landfill leachate
An autotrophic nitrogen removal process:Short-cut nitrification combined with ANAMMOX for treating diluted effluent from an UASB reactor fed by landfill leachate

Jie Liu,Jian'e Zuo,Yang Yang,Shuquan Zhu,Sulin Kuang,Kaijun Wang,
Jie Liu
,Jian’e Zuo,Yang Yang,Shuquan Zhu,Sulin Kuang,Kaijun Wang

环境科学学报(英文版) , 2010,
Abstract: A combined process consisting of a short-cut nitrification (SN) reactor and an anaerobic ammonium oxidation upflow anaerobic sludge bed (ANAMMOX) reactor was developed to treat the diluted e uent from an upflow anaerobic sludge bed (UASB) reactor treating high ammonium municipal landfill leachate. The SN process was performed in an aerated upflow sludge bed (AUSB) reactor (working volume 3.05 L), treating about 50% of the diluted raw wastewater. The ammonium removal e ciency and the ratio of NO2??- N to NOx??-N in the e uent were both higher than 80%, at a maximum nitrogen loading rate of 1.47 kg/(m3 day). The ANAMMOX process was performed in an UASB reactor (working volume 8.5 L), using the mix of SN reactor e uent and diluted raw wastewater at a ratio of 1:1. The ammonium and nitrite removal e ciency reached over 93% and 95%, respectively, after 70-day continuous operation, at a maximum total nitrogen loading rate of 0.91 kg/(m3 day), suggesting a successful operation of the combined process. The average nitrogen loading rate of the combined system was 0.56 kg/(m3 day), with an average total inorganic nitrogen removal e ciency 87%. The nitrogen in the e uent was mostly nitrate. The results provided important evidence for the possibility of applying SN-ANAMMOX after UASB reactor to treat municipal landfill leachate.
基于硝化反硝化的膜生物反应器烟气脱硝研究
Membrane Biofilm Reactor Based on Nitrification/Denitrification for Nitrogen Oxides Removal
 [PDF]

黄倩茹, 陈洲洋, 黄振山, 王剑斌, 张再利, 樊青娟, 魏在山
HUANG Qianru
,CHEN Zhouyang,HUANG Zhenshan,WANG Jianbin,ZHANG Zaili,FAN Qingjuan,WEI Zaishan

- , 2016, DOI: 10.6054/j.jscnun.2015.12.021
Abstract: 氮氧化物是形成酸雨、光化学烟雾污染、臭氧层破坏和城市灰霾天气等一系列环境问题的重要根源.文章结合课题组研究结果,介绍了空气介质下膜生物反应器烟气脱硝的性能、微生物群落、硝化反硝化烟气脱硝作用,建立了膜生物反应器传质与硝化反硝化耦合作用动力学模型;基于硝化反硝化的复合催化膜生物反应器处理模拟烟气的性能和含氧量的影响,为建立基于硝化反硝化的膜生物反应器烟气脱硝的污染控制策略提供科学依据,具有潜在的应用价值.
: Nitrogen oxides (NOx) contribute a lot to photochemical smog, acid rain, ozone depletion and urban grey haze weather. In this paper, nitrification/denitrification mechanism and the progress of membrane biofilm reactor (MBfR) on NOx removal were introduced. A polysulfone hollow-membrane biofilm reactor (MBfR) for gaseous NO removal was investigated in air medium condition. Bacterial community composition and function of nitrification/denitrification were analyzed. The kinetic model between mass transfer and NO biodegradation of MBfR were elicited. The N-TiO2/PSF hybrid catalytic membrane biofilm reactor based on nitrification/denitrification was operated for the treatment of simulated flue gas under nature light or UV irradiation, inlet O2 concentration on NO removal was evaluated. This provides a new way of flue gas denitration using a membrane biofilm reactor (MBfR) and scientific basis for potential application value
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.
固定化改性生物质炭模拟吸附水体硝态氮潜力研究  [PDF]
李丽,陈旭,吴丹,王爱丽,杨柳燕
农业环境科学学报 , 2015, DOI: 10.11654/jaes.2015.01.020
Abstract: 为了有效去除水体硝态氮污染,对两种生物质炭(花生壳炭、小麦秸秆炭)进行铁改性处理,研究其对硝态氮吸附特性,考察吸附时间、硝态氮初始浓度、pH、生物质炭添加量和共存离子对改性生物质炭吸附效果的影响.在此基础上,为解决粉末态生物质炭易随水流失的问题,对改性生物质炭进行固定化处理,探索固定化改性生物质炭对硝态氮吸附潜力.研究结果表明,改性生物质炭对硝态氮的吸附主要发生在前6h,并在24h左右达到吸附平衡,其吸附量随着水溶液中硝态氮浓度的上升而升高,改性花生壳炭和小麦秸秆炭对硝态氮最大吸附潜力分别为2674、1285mgN·kg-1,且酸性至中性条件有利于改性生物质炭对硝态氮的吸附.在20mg·L-1的硝态氮溶液中,改性花生壳炭和小麦秸秆炭的适宜固液比分别为10、28g·L-1,其去除率达到80%.当包埋载体海藻酸钠浓度为2%、改性生物质炭含量为0.1g·mL-1时,固定化改性生物质炭微球成形完整,对硝态氮具有较强的吸附能力,固定化并未显着降低改性生物质炭的吸附性能.因此,固定化改性生物质炭能有效吸附水体硝态氮,为污水处理厂尾水等低污染水硝态氮去除提供有效的技术方法.
Biological nitrogen removal by completely autotrophic processes
废水自养生物脱氮技术研究进展

WANG Shun-he,WU Wei-wei,WANG Jian-long,WANG Qun-hui,
王舜和
,吴伟伟,王建龙,汪群慧

中国生物工程杂志 , 2006,
Abstract: The conventional nitrification/denitrification process can be significantly improved through the introduction of new microbial treatment technologies ? completely autotrophic nitrogen removal processes. They're mostly based on partial nitrification combined with anaerobic ammonium oxidation, which involves in SHARON+ANAMMOX, CANON, OLAND and NOx processes. The mechanism, characteristics and differences among these processes were reviewed in this paper, and the future development was discussed.
Autotrophic Ammonium-Removal of Sludge Liquor
全程自养脱氮新技术处理污泥脱水液的研究

Yang Hong,Li Daotang,Zhu Zhangyu,
杨虹
,李道棠,朱章玉

环境科学 , 2001,
Abstract: The autotrophic ammonium-removal process was realized in floating bed reactors with sludge liquor as substrate. Biofilm of autotrophic bacteria were formed on the surface of carriers in reactors. The main operation conditions of the reactors were as the following: T = 28 degrees C, pH = 8.0 and DO = 0.8-1.0 mg/L. The average surface load of two reactors in series was NH4(+)-N 3-4 g/(m2.d), and the general autotrophic ammonium-removal efficiency was about 70%. The Autotrophic ammonium-removal technology promises considerable savings in regard to the oxygen consumption and external organic carbon addition compared with the conventional nitrification-denitrification technology when it was used to treat ammonium-rich and unfavourable C/N ratio wastewater.
软锰矿浆烟气同步脱硫脱硝资源化利用新工艺  [PDF]
廖兵,伍碧,孙维义,丁桑岚,苏仕军
环境工程 , 2013, DOI: 10.13205/j.hjgc.201302016
Abstract: 燃煤烟气中的SO2和NOx是大气中重要的污染物,开发高效、经济的同步脱硫脱硝技术是环保领域的研究热点。针对现有同步脱硫脱硝技术存在的氧化剂成本较高和产物不能资源化利用等突出问题,提出了软锰矿浆烟气同步脱硫脱硝,并副产硫酸锰和硝酸锰的资源化新工艺。研究结果表明软锰矿浆可以有效的脱除烟气中的SO2和NOx,反应产物分别为硫酸锰和硝酸锰。在烟道中注入臭氧,将难溶于水的NO快速氧化为NO2,可大大提高脱硝效率,在O3/NO=1.2的条件下可以达到72%的脱硝率、90%的脱硫率和85%的锰浸出率;吸收液经过空气氧化除铁和加入铜试剂除重金属后,结晶分离溶液得到的硫酸锰和硝酸锰可分别达到HG/T2962—1999标准的硫酸锰产品和HG/T3817—2006标准的工业硝酸锰产品要求。该工艺实现了SO2和NOx污染治理与低品位软锰矿资源化利用的双重目的,为SO2和NOx的资源化污染治理技术的开发和应用提供了新的思路。
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