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simultaneous nitrification and autotrophic denitrification in fluidized bed reactors using pyrite and elemental sulfur as electron donors

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Water Science and Engineering 2023年第2期16卷 143-153页

作者： Maria F.Carboni Sonia Arriaga Piet N.L.Lens National University of Ireland Galway H91 TK33 GalwayIreland Instituto Potosino de Investigación Científica y Tecnológica 78216 San Luis PotosíMexico

In this study, simultaneous nitrification and autotrophic denitrification (SNAD) with either elemental sulfur or pyrite were investigated in fluidized bed reactors in mesophilic conditions. The reactor performance was evaluated at different ammonium (12-40 mg/L of NH4+-N), nitrate (35-45 mg/L of NO3--N), and dissolved oxygen (DO) (0.1-1.5 mg/L) concentrations, with a hydraulic retention time of 12 h. The pyrite reactor supported the SNAD process with a maximum nitrogen removal efficiency of 139.5 mg/(L·d) when the DO concentration was in the range of 0.8-1.5 mg/L. This range, however, limited the denitrification efficiency of the reactor, which decreased from 90.0% ± 5.3% in phases II-V to 67.9% ± 7.2% in phases VI and VII. Sulfate precipitated as iron sulfate (FeSO4/Fe2(SO4)3) and sodium sulfate (Na2SO4) minerals during the experiment. The sulfur reactor did not respond well to nitrification with a low and unstable ammonium removal efficiency, while denitrification occurred with a nitrate removal efficiency of 97.8%. In the pyrite system, the nitrifying bacterium Nitrosomonas sp. was present, and its relative abundance increased from 0.1% to 1.1%, while the autotrophic denitrifying genera Terrimonas, Ferruginibacter, and Denitratimonas dominated the community. Thiobacillus, Sulfurovum, and Trichlorobacter were the most abundant genera in the sulfur reactor during the entire experiment.

关键词： Pyrite Elemental sulfur simultaneous nitrification and denitrification Nitrogen removal 16S rRNA

Nitrogen removal and simultaneous nitrification and denitrification in a fluidized bed step-feed process

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Journal of Environmental Sciences 2012年第2期24卷 303-308页

作者： BingWang Wei Wang Hongjun Han Hongbo Hu Haifeng Zhuang State Key Laboratory of Urban Water Resources and Environment （SKLUWRE） Harbin Institute of Technology Harbin 150090 China Municipal ＆ Environmental Engineering College Shenyang Jianzhu University Shenyang 110168 China School of Civil and Hydraulic Engineering Hefei University of Technology Hefei 230009 China

For urban wastewater treatment,we conducted a novel four-stage step-feed wastewater treatment system combined with a fluidized bed laboratory experiment to investigate chemical oxygen demand（COD）,NH4＋-N,and total nitrogen（TN） removal performance.The removal rates of COD,NH4＋-N and TN were 88.2%,95.7%,and 86.4% with e？uent concentrations of COD,NH4＋-N and TN less than 50,8,and 10 mg/L,respectively.Biomass and bacterial activities were also measured,with results showing more nitrobacteria in the activated sludge than in the biofilm;however,bacterial activity of the biofilm biomass and the activated sludge were similar.Nitrogen concentrations during the process were also detected,with simultaneous nitrification and denitrification found to be obvious.

关键词： denitrification fluidized bed step-feed simultaneous nitrification and denitrification

simultaneous nitrification and denitrification by aerobic granular sludge membrane bioreactor for high concentration ammonium nitrogen wastewater

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Acta Geochimica 2006年第S1期 130-131页

作者： Rui CHEN1, Xiaoli WANG2, Yonggang ZHANG1, Xueqi FU1 1 College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China2 College of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300071, China

Factors affecting simultaneous nitrification and denitrification in an SBBR treating domestic wastewater

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Frontiers of Environmental Science & Engineering 2007年第2期1卷 246-250页

作者： LI Jun PENG Yongzhen GU Guowei WEI Su College of Environmental Science and Engineering Tongji UniversityShanghai 200092China College of Environment and Energy Sources Beijing University of TechnologyBeijing 100022China College of Civil Engineering Zhejiang University of TechnologyHangzhou 310014China

An aerobic sequencing batch biofilm reactor(SBBR)packed with Bauer rings was used to treat real domestic wastewater for simultaneous nitrification and deni-trification.The SBBR is advantageous for creating an anoxic condition,and the biofilm can absorb and store carbon for good nitrification and denitrification.An average concentra-tion of oxygen ranging from 0.8 to 4.0 mg/L was proved very efficient for nitrification and denitrification.Volumetric loads of TN dropped dramatically and effluent TN concentra-tion increased quickly when the concentration of average dissolved oxygen was more than 4.0 mg/L.The efficiency of simultaneous nitrification and denitrification(SND)increased with increasing thickness of the biofilm.The influent concen-tration hardly affected the TN removal efficiency,but the effluent TN increased with increasing influent concentration.It is suggested that a subsequence for denitrification be added or influent amount be decreased to meet effluent quality requirements.At optimum operating parameters,the TN removal efficiency of 74%-82%could be achieved.

关键词： sequencing batch biofilm reactor(SBBR) simultaneous nitrification and denitrification dissolved oxygen biofilm influent concentration

Moving Bed Biofilm Reactor simultaneous nitrification-denitrification Studies

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Moving Bed Biofilm Reactor Simultaneous Nitrification-Denitr...

Community analysis of ammonia and nitrite oxidizers in start-up of aerobic granular sludge reactor

The 3rd International Conference on Environmental Technology and Knowledge Transfer

作者： GE Zhigang (Department of Biological and Chemical Engineering Jiaxing University Jiaxing 314001 China)

This research carried out wastewater treatment tests in a filature factory by using moving bed biofilm reactor.After moving-bed start-up experiment,simultaneous nitrification and denitrification process in a single representative cycle was analyzed,and the effect of C/N on wastewater treatment was studied.The results showed that 21d after the start-up experiment the removal rates of CODCr and NH4+-N stayed above 80%.This indicated the success of the start-up experiment.When the concentration of DO was around 3.0mg/L,simultaneous nitrification and denitrification occurred in the reactor.Through modulating C/N by adding in methanol,the removal rates of NH4+-N was above 93%.With the rise of the C/N,the removal rates of TN were also increased.When the C/N was 10,the maximum TN removal rates can reach 88.6%.However,when C/N increased to 12,TN removal rates no longer increased but stabilized at around 84%.

关键词： moving bed biofilm reactor C/N simultaneous nitrification and denitrification removal rates

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Journal of Environmental Sciences 2007年第8期19卷 996-1002页

作者： WANG Feng XIA Si-qing LIU Yi CHEN Xue-song ZHANG Jun State Key Laboratory of PoUution Control and Resource Reuse School of Environmental Science and Engineering Tongji University Shanghai 200092 China. College of Biology and Environment Engineering Zhejiang Shuren University Hangzhou 310015 China Medical School Tongji University Shanghai 200092 China

A lab-scale sequencing batch reactor （SBR） was set-up and the aerobic granular sludge was successfully incubated using anaerobic granular sludge as seed sludge. Nitrogen was partially removed by simultaneous nitrification and denitrification （SND） via nitrite with free ammonia （FA） of about 10 mg/L. The denaturing gradient gel electrophoresis （DGGE） method was used to investigate community structure of α-Proteobacteria, β-Proteobacteria, ammonia oxidizing bacteria （AOB）, and Nitrospira populations during start-up. The population sizes of bacteria, AOB and Nitrospira were examined using real-time PCR method. The analysis of community structure and Shannon index showed that stable structure of AOB population was obtained at day 35, while the communities of α- Proteobacteria, β-Proteobacteria, and Nitrospira became stable after day 45. At stable stage, the average cell densities were 1.1× 10^12, 2.2×10^10 and 1.0×10^10 cells/L for bacteria, AOB and Nitrospira, respectively. The relationship between characteristics of nitrifying bacteria community and nitrogenous substrate utilization constant was discussed by calculating Pearson correlation. Certain correlation seemed to exist between population size, biodiversity, and degradation constant. And the influence of population size might be greater than that of biodiversity.

关键词： aerobic granular sludge simultaneous nitrification and denitrification nitrite accumulation denaturing gradient gel electrophoresis real-time PCR

Novel strategy of nitrogen removal from domestic wastewater using pilot Orbal oxidation ditch

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Journal of Environmental Sciences 2006年第5期18卷 833-839页

作者： GAO Shou-you PENG Yong-zhen WANG Shu-ying YAN Jun School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China. College of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China

A pilot-scale Orbed oxidation ditch was operated for 17 months to optimize nitrogen removal from domestic wastewater of average COD to total nitrogen ratio of 2.7, with particular concern about the roles of dissolved oxygen （DO）, mixed liquor suspended solids （MLSS） and return activated sludge （RAS） recycle ratio. Remarkable simultaneous nitrification and denitrification （SND） was observed and mean total nitrogen （TN） removal efficiency up to 72.1% was steadily achieved, at DO concentration in the out, middle and inner channel of 0.1, 0.4 and 0.7 mg/L, respectively, with an average M LSS of 5.5 g/L and RAS recycle ratio of 150%. Although the out channel took the major role in TN removal, the role of middle channel should never be ignored. The denitrification potential could be fully developed under low DO, high MLSS with adequate RAS ratio. The sludge settleability was amazingly improved under low DO operation mode, and some explanations were tried. In addition, a scries of simplified batch tests were done to determine whether novel microorganisms could make substantial contribution to the performance of nitrogen removal. The results indicated that the SND observed in this Orbal oxidation ditch was more likely a physical phenomenon.

关键词： nitrogen removal simultaneous nitrification and denitrification low DO MLSS novel bacterial

Nitrifying and denitrifying bacteria in aerobic granules formed in sequencing batch airlift reactors

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Frontiers of Environmental Science & Engineering 2007年第2期1卷 184-189页

作者： WANG Fang YANG Fenglin QI Aijiu Department of Environmental Engineering Dalian Nationalities UniversityDalian 116600China School of Environmental and Biological Science and Technology Dalian University of TechnologyDalian 116023China

The purpose of this study was to investigate nitrifying bacteria and denitrifying bacteria isolated from aerobic granules.Aerobic granules were formed in an internal-circulate sequencing batch airlift reactor(SBAR)and biodegradation of NH_(3)^(−)-N was analyzed in the reactor.Bacteria were isolated and determined from aerobic granules using selected media.The growth properties and morphology of bacteria colonies were observed by controlling aerobic or anaerobic conditions in the culture medium.It was found that bacteria in aerobic granules were diverse and some of them were facultative aerobes.The diversity of bacteria in aerobic granules was a premise of simultaneous nitrification and denitrification.

关键词： aerobic granular sludge simultaneous nitrification and denitrification facultative aerobe

Complex Biological Technology in the City’s Sewage Treatment Plant Upgrading and Reconstruction of the Application

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Complex Biological Technology in the City’s Sewage Treatmen...