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Sample records for anaerobic ammonium-oxidizing anammox

  1. Inactivation of ANAMMOX communities under concurrent operation of anaerobic ammonium oxidation (ANAMMOX) and denitrification

    DEFF Research Database (Denmark)

    Chamchoi, N.; Nitisoravut, S.; Schmidt, Jens Ejbye

    2008-01-01

    A concurrent operation of anaerobic ammonium oxidation (ANAMMOX) and denitrification was investigated in a well known UASB reactor seeding with both ANAMMOX and anaerobic granular sludges. ANAMMOX activity was confirmed by hydroxylamine test and the hybridization of biomass using the gene probes of......–nitrate concentrations in all reactors confirmed the undergone concurrent denitrification which thrives when sufficient organic matter is available. COD concentration over 300 mg l−1 was found to inactivate or eradicate ANAMMOX communities....

  2. Enrichment culture of marine anaerobic ammonium oxidation (anammox) bacteria

    Institute of Scientific and Technical Information of China (English)

    GUAN Yong-jie

    2016-01-01

    The present study investigates the enrichment of anaerobic ammonium oxidation (anammox) bacteria in the marine environment using sediment samples obtained from the East China Sea and discusses the nitrogen removal efficiency of marine anammox bioreactor. Enrichment of anammox bacteria with simultaneous removal of nitrite and ammonium ions was observed in the Anaerobic Sequencing Batch Reactor under a total nitrogen loading rate of 0.37kg-N m-3day-1. In this study, The nitrogen removal efficiency was up to 80% and the molar-reaction ratio of ammonium, nitrite and nitrate was 1.0:1.22:0.22 which was a little different from a previously reported ratio of 1.0:1.32:0.26 in a freshwater system.

  3. Evaluation on the microbial interactions of anaerobic ammonium oxidizers and heterotrophs in Anammox biofilm

    DEFF Research Database (Denmark)

    Ni, Bing-Jie; Ruscalleda, Mael; Smets, Barth F.

    2012-01-01

    Anaerobic ammonium oxidation (Anammox) is a cost-effective new process to treat high-strength nitrogenous wastewater. In this work, the microbial interactions of anaerobic ammonium oxidizers and heterotrophs through the exchange of soluble microbial products (SMP) in Anammox biofilm and the affec...

  4. Influence of preservation temperature on the characteristics of anaerobic ammonium oxidation (anammox) granular sludge.

    Science.gov (United States)

    Xing, Bao-Shan; Guo, Qiong; Jiang, Xiao-Yan; Chen, Qian-Qian; Li, Peng; Ni, Wei-Min; Jin, Ren-Cun

    2016-05-01

    Preserving active anaerobic ammonium oxidation (anammox) biomass is a potential method for securing sufficient seeding biomass for the rapid start-up of full-scale anammox processes. In this study, anammox granules were cultured in an upflow anaerobic sludge blanket (UASB) reactor (R0), and then the enriched anammox granules were preserved at 35, 20, 4, and -30 °C. The subsequent reactivation characteristics of the granules were evaluated in four UASB reactors (denoted R1, R2, R3, and R4, respectively) to investigate the effect of preservation temperature on the characteristics of anammox granules and their reactivation performance. The results demonstrated that 4 °C was the optimal preservation temperature for maintaining the biomass, activity, settleability, and integrity of the anammox granules and their cellular structures. During the preservation period, a first-order exponential decay model may be used to simulate the decay of anammox biomass and activity. The protein-to-polysaccharide ratio in the extracellular polymeric substances and the heme c content could not effectively indicate the changes in settleability and activity of the anammox granules, respectively, and a loss of bioactivity was positively associated with the degree of anaerobic ammonium-oxidizing bacteria cell lysis. After 42 days of storage, the anammox granules preserved at 4 °C (R3) exhibited a better recovery performance than those preserved at 20 °C (R2), -30 °C (R4), and 35 °C (R1). The comprehensive comparison indicated that 4 °C is the optimal storage temperature for anammox granular sludge because it promotes improved maintenance and recovery performance properties. PMID:26780355

  5. Anaerobic ammonium oxidation by anammox bacteria in the Black Sea RID B-8834-2011

    DEFF Research Database (Denmark)

    Kuypers, MMM; Sliekers, AO; Lavik, G.; Schmid, M.; Jørgensen, BB; Kuenen, JG; Damste, JSS; Strous, M.; Jetten, MSM

    2003-01-01

    ). Here we provide evidence for bacteria that anaerobically oxidize ammonium with nitrite to N(2) in the world's largest anoxic basin, the Black Sea. Phylogenetic analysis of 16S ribosomal RNA gene sequences shows that these bacteria are related to members of the order Planctomycetales performing the...... anammox (anaerobic ammonium oxidation) process in ammonium-removing bioreactors(3). Nutrient profiles, fluorescently labelled RNA probes, (15)N tracer experiments and the distribution of specific 'ladderane' membrane lipids(4) indicate that ammonium diffusing upwards from the anoxic deep water is consumed...

  6. Anaerobic Ammonium-Oxidizing (Anammox) Bacteria and Associated Activity in Fixed-Film Biofilters of a Marine Recirculating Aquaculture System†

    OpenAIRE

    Tal, Yossi; Joy E M Watts; Schreier, Harold J.

    2006-01-01

    Microbial communities in the biological filter and waste sludge compartments of a marine recirculating aquaculture system were examined to determine the presence and activity of anaerobic ammonium-oxidizing (anammox) bacteria. Community DNA was extracted from aerobic and anaerobic fixed-film biofilters and the anaerobic sludge waste collection tank and was analyzed by amplifying 16S rRNA genes by PCR using anammox-selective and universal GC-clamped primers. Separation of amplified PCR product...

  7. Role of Anaerobic Ammonium Oxidation (Anammox) in Nitrogen Removal from a Freshwater Aquifer.

    Science.gov (United States)

    Smith, Richard L; Böhlke, J K; Song, Bongkeun; Tobias, Craig R

    2015-10-20

    Anaerobic ammonium oxidation (anammox) couples the oxidation of ammonium with the reduction of nitrite, producing N2. The presence and activity of anammox bacteria in groundwater were investigated at multiple locations in an aquifer variably affected by a large, wastewater-derived contaminant plume. Anammox bacteria were detected at all locations tested using 16S rRNA gene sequencing and quantification of hydrazine oxidoreductase (hzo) gene transcripts. Anammox and denitrification activities were quantified by in situ (15)NO2(-) tracer tests along anoxic flow paths in areas of varying ammonium, nitrate, and organic carbon abundances. Rates of denitrification and anammox were determined by quantifying changes in (28)N2, (29)N2, (30)N2, (15)NO3(-), (15)NO2(-), and (15)NH4(+) with groundwater travel time. Anammox was present and active in all areas tested, including where ammonium and dissolved organic carbon concentrations were low, but decreased in proportion to denitrification when acetate was added to increase available electron supply. Anammox contributed 39-90% of potential N2 production in this aquifer, with rates on the order of 10 nmol N2-N L(-1) day(-1). Although rates of both anammox and denitrification during the tracer tests were low, they were sufficient to reduce inorganic nitrogen concentrations substantially during the overall groundwater residence times in the aquifer. These results demonstrate that anammox activity in groundwater can rival that of denitrification and may need to be considered when assessing nitrogen mass transport and permanent loss of fixed nitrogen in aquifers. PMID:26401911

  8. Anaerobic ammonium oxidation by Nitrosomonas spp. and anammox bacteria in a sequencing batch reactor.

    Science.gov (United States)

    Lek Noophan, Pongsak; Sripiboon, Siriporn; Damrongsri, Mongkol; Munakata-Marr, Junko

    2009-02-01

    A sequencing batch reactor (SBR) was inoculated with mixed nitrifying bacteria from an anoxic tank at the conventional activated sludge wastewater treatment plant in Nongkhaem, Bangkok, Thailand. This enriched nitrifying culture was maintained under anaerobic conditions using ammonium (NH(4)(+)) as an electron donor and nitrite (NO(2)(-)) as an electron acceptor. Autotrophic ammonium oxidizing bacteria survived under these conditions. The enrichment period for anammox culture was over 100 days. Both ammonium and nitrite conversion rates were proportional to the biomass of ammonium oxidizing bacteria; rates were 0.08 g N/gV SS/d and 0.05 g N/g VSS/d for ammonium and nitrite, respectively, in a culture maintained for 3 months at 42 mg N/L ammonium. The nitrogen transformation rate at a ratio of NH(4)(+)-N to NO(2)(-)-N of 1:1.38 was faster, and effluent nitrogen levels were lower, than at ratios of 1:0.671, 1:2.18, and 1:3.05. Fluorescent in situ hybridization (FISH) was used to identify specific autotrophic ammonium oxidizing bacteria (Nitrosomonas spp., Candidatus Brocadia anammoxidans, and Candidatus Kuenenia stuttgartiensis). The ammonium oxidizing culture maintained at 42 mg N/L ammonium was enriched for Nitrosomonas spp. (30%) over Candidati B. anammoxidans and K. stuttgartiensis (2.1%) while the culture maintained at 210 mg N/L ammonium was dominated by Candidati B. anammoxidans and K. stuttgartiensis (85.6%). The specific nitrogen removal rate of anammox bacteria (0.6 g N/g anammox VSS/d) was significantly higher than that of ammonium oxidizing bacteria (0.4 g N/g Nitrosomonas VSS/d). Anammox bacteria removed up to 979 mg N/L/d of total nitrogen (ammonium:nitrite concentrations, 397:582 mg N/L). These results suggest significant promise of this approach for application to wastewater with high nitrogen but low carbon content, such as that found in Bangkok. PMID:18423965

  9. Hydroxylamine-dependent Anaerobic Ammonium Oxidation (Anammox) by “ Candidatus Brocadia sinica”

    KAUST Repository

    Oshiki, Mamoru

    2016-04-26

    Although metabolic pathways and associated enzymes of anaerobic ammonium oxidation (anammox) of “Ca. Kuenenia stuttgartiensis” have been studied, those of other anammox bacteria are still poorly understood. NO2- reduction to NO is considered to be the first step in the anammox metabolism of “Ca. K. stuttgartiensis”, however, “Ca. Brocadia” lacks the genes that encode canonical NO-forming nitrite reductases (NirS or NirK) in its genome, which is different from “Ca. K. stuttgartiensis”. Here, we studied the anammox metabolism of “Ca. Brocadia sinica”. 15N-tracer experiments demonstrated that “Ca. B. sinica” cells could reduce NO2- to NH2OH, instead of NO, with as yet unidentified nitrite reductase(s). Furthermore, N2H4 synthesis, downstream reaction of NO2- reduction, was investigated using a purified “Ca. B. sinica” hydrazine synthase (Hzs) and intact cells. Both the “Ca. B. sinica” Hzs and cells utilized NH2OH and NH4+, but not NO and NH4+, for N2H4 synthesis and further oxidized N2H4 to N2 gas. Taken together, the metabolic pathway of “Ca. B. sinica” is NH2OH-dependent and different from the one of “Ca. K. stuttgartiensis”, indicating metabolic diversity of anammox bacteria. This article is protected by copyright. All rights reserved.

  10. Development of Electroactive and Anaerobic Ammonium-Oxidizing (Anammox Biofilms from Digestate in Microbial Fuel Cells

    Directory of Open Access Journals (Sweden)

    Enea Gino Di Domenico

    2015-01-01

    Full Text Available Microbial Fuel cells (MFCs have been proposed for nutrient removal and energy recovery from different wastes. In this study the anaerobic digestate was used to feed H-type MFC reactors, one with a graphite anode preconditioned with Geobacter sulfurreducens and the other with an unconditioned graphite anode. The data demonstrate that the digestate acts as a carbon source, and even in the absence of anode preconditioning, electroactive bacteria colonise the anodic chamber, producing a maximum power density of 172.2 mW/m2. The carbon content was also reduced by up to 60%, while anaerobic ammonium oxidation (anammox bacteria, which were found in the anodic compartment of the reactors, contributed to nitrogen removal from the digestate. Overall, these results demonstrate that MFCs can be used to recover anammox bacteria from natural sources, and it may represent a promising bioremediation unit in anaerobic digestor plants for the simultaneous nitrogen removal and electricity generation using digestate as substrate.

  11. Anaerobic ammonium oxidation (anammox) bacterial diversity, abundance, and activity in marsh sediments of the Yangtze Estuary

    Science.gov (United States)

    Hou, Lijun; Zheng, Yanling; Liu, Min; Gong, Jun; Zhang, Xiaoli; Yin, Guoyu; You, Li

    2013-07-01

    ammonium oxidation (anammox) as an important process of nitrogen cycle has been studied in estuarine environments. However, knowledge about the dynamics of anammox bacteria and their interactions with associated activity remains scarce in these environments. Here we report the anammox bacterial diversity, abundance, and activity in the Yangtze Estuary, using molecular and isotope-tracing techniques. The phylogenetic analysis of 16S rRNA indicated that high anammox bacterial diversity occurred in this estuary, including Scalindua, Brocadia, Kuenenia, and two novel clusters. The patterns of community composition and diversity of anammox bacteria differed across the estuary. Salinity was a key environmental factor defining the geographical distribution and diversity of the anammox bacterial community at the estuarine ecosystem. Temperature and organic carbon also had significant influences on anammox bacterial biodiversity. The abundance of anammox bacteria ranged from 2.63 × 106 and 1.56 × 107 gene copies g-1, and its spatiotemporal variations were related significantly to salinity, temperature, and nitrite content. The anammox activity was related to temperature, nitrite, and anammox bacterial abundance, with values of 0.94-6.61 nmol N g-1 h-1. The tight link between the anammox and denitrification processes implied that denitrifying bacteria may be a primary source of nitrite for the anammox bacteria in the estuarine marshes. On the basis of the 15N tracing experiments, the anammox process was estimated to contribute 6.6%-12.9% to the total nitrogen loss whereas the remainder was attributed to denitrification.

  12. Exogenous nitrate attenuates nitrite toxicity to anaerobic ammonium oxidizing (anammox) bacteria.

    Science.gov (United States)

    Li, Guangbin; Vilcherrez, David; Carvajal-Arroyo, Jose Maria; Sierra-Alvarez, Reyes; Field, Jim A

    2016-02-01

    Anaerobic ammonium oxidizing bacteria (anammox) can be severely inhibited by one of its main substrates, nitrite (NO2(-)). At present, there is limited information on the processes by which anammox bacteria are able to tolerate toxic NO2(-). Intracellular consumption or electrochemically driven (transmembrane proton motive force) NO2(-) export are considered the main mechanisms of NO2(-) detoxification. In this work, we evaluated the potential of exogenous nitrate (NO3(-)) on relieving NO2(-) toxicity, putatively facilitated by NarK, a NO3(-)/NO2(-) transporter encoded in the anammox genome. The relative contribution of NO3(-) to NO2(-) detoxification was found to be pH dependent. Exposure of anammox cells to NO2(-) in absence of their electron donating substrate, ammonium (NH4(+)), causes NO2(-) stress. At pH 6.7 and 7.0, the activity of NO2(-) stressed cells was respectively 0 and 27% of the non-stressed control activity (NO2(-) and NH4(+) fed simultaneously). Exogenous NO3(-) addition caused the recovery to 42% and 80% of the control activity at pH 6.7 and 7.0, respectively. The recovery of the activity of NO2(-) stressed cells improved with increasing NO3(-) concentration, the maximum recovery being achieved at 0.85 mM. The NO3(-) pre-incubation time is less significant at pH 7.0 than at pH 6.7 due to a more severe NO2(-) toxicity at lower pH. Additionally, NO3(-) caused almost complete attenuation of NO2(-) toxicity in cells exposed to the proton gradient disruptor carbonyl cyanide m-chlorophenyl hydrazone at pH 7.5, providing evidence that the NO3(-) attenuation is independent of the proton motive force. The absence of a measurable NO3(-) consumption (or NO3(-) dependent N2 production) during the batch tests leaves NO3(-) dependent active transport of NO2(-) as the only plausible explanation for the relief of NO2(-) inhibition. We suggest that anammox cells can use a secondary transport system facilitated by exogenous NO3(-) to alleviate NO2(-) toxicity. PMID

  13. Anaerobic ammonium-oxidizing (anammox) bacteria and associated activity in fixed-film biofilters of a marine recirculating aquaculture system.

    Science.gov (United States)

    Tal, Yossi; Watts, Joy E M; Schreier, Harold J

    2006-04-01

    Microbial communities in the biological filter and waste sludge compartments of a marine recirculating aquaculture system were examined to determine the presence and activity of anaerobic ammonium-oxidizing (anammox) bacteria. Community DNA was extracted from aerobic and anaerobic fixed-film biofilters and the anaerobic sludge waste collection tank and was analyzed by amplifying 16S rRNA genes by PCR using anammox-selective and universal GC-clamped primers. Separation of amplified PCR products by denaturing gradient gel electrophoresis and sequencing of the different phylotypes revealed a diverse biofilter microbial community. While Planctomycetales were found in all three communities, the anaerobic denitrifying biofilters contained one clone that exhibited high levels of sequence similarity to known anammox bacteria. Fluorescence in situ hybridization studies using an anammox-specific probe confirmed the presence of anammox Planctomycetales in the microbial biofilm from the denitrifying biofilters, and anammox activity was observed in these biofilters, as detected by the ability to simultaneously consume ammonia and nitrite. To our knowledge, this is the first identification of anammox-related sequences in a marine recirculating aquaculture filtration system, and our findings provide a foundation for incorporating this important pathway for complete nitrogen removal in such systems. PMID:16597996

  14. Molecular and Stable Isotope Investigation of Nitrite Respiring Bacterial Communities Capable of Anaerobic Ammonium Oxidation (ANAMMOX) and Denitrifying Anaerobic Methane Oxidation (DAMO) in Nitrogen Contaminated Groundwater

    Science.gov (United States)

    Song, B.; Hirsch, M.; Taylor, J.; Smith, R. L.; Repert, D.; Tobias, C. R.

    2010-12-01

    Anaerobic ammonium oxidation (ANAMMOX) and denitrifying anaerobic methane oxidation (DAMO) are two recently discovered N2 production pathways in the microbial nitrogen cycle. ANAMMOX has been relatively well investigated in various aquatic ecosystems, while DAMO has been examined only in freshwater wetlands. However, neither ANAMMOX nor DAMO have been studied in groundwater ecosystems as microbial N removal processes where they could compliment or compete with denitrification to remediate N contaminated aquifers. Thus, we conducted molecular and stable isotope analyses to detect and measure ANAMMOX and DAMO in a nitrogen contaminated aquifer on Cape Cod, Massachusetts. The study site has a plume of nitrogen contaminated groundwater as a result of continuous discharge of treated wastewater over 60 years. Groundwater was collected from multiport sampling devices installed at two sites, near the waste-water disposal location (A) and more than 3 km down gradient (B) along the contamination plume. Biomass was collected from water samples for DNA extraction and 15N tracer incubation experiments. PCR with specific 16S rRNA gene primers detected the presence of ANAMMOX and DAMO bacteria at both sites. Phylogenetic analysis of 16S rRNA genes revealed that the ANAMMOX community at site A was most associated with Kuenenia spp. while site B had a community more closely related to Brocadia spp. The DAMO communities at the two sites were quite different based on 16S rRNA gene analysis. The communities at site B are closely associated with Candidatus “Methylomirabilis oxyfera”, which is the first enriched DAMO culture. Most of the 16S rRNA sequences detected in site A were related to those found in other DAMO enrichment cultures established from a eutrophic ditch sediment. In order to determine active members of ANAMMOX communities, the transcriptional expression of hydrazine oxidase (hzo) and hydrazine hydrolase (hh) genes was examined at both sites. In addition, 15N tracer

  15. Effects of inorganic carbon limitation on anaerobic ammonium oxidation (anammox) activity.

    Science.gov (United States)

    Kimura, Yuya; Isaka, Kazuichi; Kazama, Futaba

    2011-03-01

    Anammox bacteria are chemoautotrophic bacteria that oxidize ammonium with nitrite as the electron acceptor and with CO(2) as the main carbon source. The effects of inorganic carbon (IC) limitation on anammox bacteria were investigated using continuous feeding tests. In this study, a gel carrier with entrapped anammox sludge was used. It was clearly shown that the anammox activity deteriorated with a decrease in the influent IC concentration. The relationship between the influent IC concentration and the anammox activity was analyzed using Michaelis-Menten kinetics, and the apparent K(m) was determined to be 1.2mg-C/L. The activity could be recovered by adding IC to the influent. The consumption ratio of IC to ammonium was not constant and mainly depended on the influent ratio of the IC to ammonium concentrations (inf.IC/inf.NH(4)-N). The results indicated that an inf.IC/inf.NH(4)-N ratio of 0.2 in the anammox reactor was ideal for the anammox process using gel cubes. PMID:21256745

  16. High-rate partial nitrification treatment of reject water as a pretreatment for anaerobic ammonium oxidation (anammox).

    Science.gov (United States)

    Zhang, Li; Yang, Jiachun; Hira, Daisuke; Fujii, Takao; Furukawa, Kenji

    2011-02-01

    In this study, a lab-scale swim-bed partial nitrification reactor was developed to treat ammonium-rich reject water to achieve an appropriate NO(2)(-)-N/NH(4)(+)-N mixture that could serve as a pretreatment for anaerobic ammonium oxidation (anammox). Strictly controlling the DO concentration was adopted as the main operational strategy. In addition, the influent concentrations of inorganic carbon/ammonium (IC/NH(4)(+)) and alkalinity/ammonium (Alk/NH(4)(+)) that were approximately 0.8 and 4.8, respectively, were regarded as the suitable ratios for the steady and high-rate operation of the reactor in this study. When reject water that was not diluted was introduced to this system, the maximum nitrogen loading rate was 5.9 kg-N/m(3)/day, the ammonium conversion rate was 3.1 kg-N/m(3)/day, and the effluent NO(2)-N/(NO(2)-N+NO(3)-N) percentage ratio was over 99.9%. Furthermore, DNA analysis confirmed the existence of AOB, which was responsible for the stable performance that was achieved in the PN reactor. PMID:21190840

  17. Anaerobic Ammonium-Oxidizing Bacteria: Unique Microorganisms with Exceptional Properties

    OpenAIRE

    Niftrik, L.A.M.P. van; Jetten, M.S.M.

    2012-01-01

    Summary: Anaerobic ammonium-oxidizing (anammox) bacteria defy many microbiological concepts and share numerous properties with both eukaryotes and archaea. Among their most intriguing characteristics are their compartmentalized cell plan and archaeon-like cell wall. Here we review our current knowledge about anammox cell biology. The anammox cell is divided into three separate compartments by bilayer membranes. The anammox cell consists of (from outside to inside) the cell wall, paryphoplasm,...

  18. How to make a living from anaerobic ammonium oxidation

    NARCIS (Netherlands)

    Kartal, B.; De Almeida, N.M.; Maalcke, W.J.; Op den Camp, H.J.M.; Jetten, M.S.M.; Keltjens, J.T.

    2013-01-01

    Anaerobic ammonium-oxidizing (anammox) bacteria primarily grow by the oxidation of ammonium coupled to nitrite reduction, using CO2 as the sole carbon source. Although they were neglected for a long time, anammox bacteria are encountered in an enormous species (micro)diversity in virtually any anoxi

  19. Correlation of anaerobic ammonium oxidation and denitrification

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The feasibility of the nitrous organic wastewater treated was studied in seven anaerobic sequencing batch reactors(ASBRs)(0 #-6 #) which had been run under stable anaerobic ammonium oxidation (Anammox). By means of monitoring and data analysis of COD, NH4+-N, NO2--N, NO3--N and pH, and of microbial test, the results revealed that the optimal Anammox performance was achieved from 2# reactor in which COD/NH4+-N was 1.65, Anammox bacteria and denitrification bacteria could coexist, and Anammox reaction and denitrification reaction could occur simultaneously in the reactors. The ratio of NH4+-N consumed: NO2--N consumed: NO3--N produced was 1:1.38:0.19 in 0# reactor which was not added glucose in the wastewater. When different ratio of COD and NH4+-N was fed for the reactors, the ratio of NO2--N consumed: NH4+-N consumed was in the range of 1.51-2.29 and the ratio of NO3-N produced: NH4+-N consumed in the range of 0-0.05.

  20. Start-up of simultaneous removal of ammonium and sulfate from an anaerobic ammonium oxidation (anammox) process in an anaerobic up-flow bioreactor

    International Nuclear Information System (INIS)

    A laboratory testing of simultaneous removal of ammonium and sulfate (SRAS) was studied from an anammox process in an anaerobic bioreactor filled with granular activated carbon. Two different phases of experiment were investigated to start up the SRAS process, and final batch tests were performed to analyze the SRAS process. The experiment included an anammox process and an SRAS process. During the anammox process, the highest removal efficiency of ammonium and nitrite was up to 97 and 98%, respectively. After 160 days in the stationary phase of anammox process, the ratio of ammonium to nitrite consumption was approximately 1:1.15, which is much higher than 1:1.32 in the traditional anammox process. The extra electron acceptor, such as sulfate, was thought to react with ammonium by bacteria. Synthetic wastewater containing ammonium chlorine and sodium sulfate was used as the feed for the bioreactor in the second phase of experiment. During the SRAS process, the influent concentrations of ammonium and sulfate were controlled to be 50-60 and 210-240 mg L-1 respectively. After start-up and acclimatization of this process for 60 days, the average effluent concentrations of ammonium and sulfate were 30 and 160 mg L-1, respectively. The simultaneous ammonium and sulfate removal was detected in the reactor. In order to further validate the biochemical interaction between ammonium and sulfate, batch tests was carried out. Abiotic tests were carried out to demonstrate that the pure chemical action between ammonium and sulfate without microorganism was not possible. Biotic assays with different ammonium and sulfate concentrations were further investigated that high concentrations of ammonium and sulfate could promote simultaneous removal of ammonium and sulfate. And elemental sulfur and nitrogen gas as the products measured in the SRAS process helped to demonstrate the occurrence of new interaction between nitrogen and sulfur. The new process of SRAS in the inorganic

  1. Treating leachate mixture with anaerobic ammonium oxidation technology

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-guo; ZHOU Shao-qi

    2006-01-01

    Large amounts of ammonium and a low content of biodegradable chemical oxygen demand(COD) are contained in leachate from aged landfills, together with the effluent containing high concentration of nitric nitrogen after biochemical treatment.Treatment effect of anaerobic ammonium oxidation (anammox) process on the mixture of the leachate and its biochemical effluent was investigated. The results show that the average removal efficiencies of ammonium, nitric nitrogen and total nitrogen are 87.51%,74.95% and 79.59%, respectively, corresponding to the average ratio of removed nitric nitrogen to ammonium, i.e. 1.14 during the steady phase of anammox activity. The mean removal efficiency of COD is only 24.01% during the experimental period. The demand of total phosphorous for the anammox process is unobvious. Especially, the alkalinity and pH value of the effluent are close to those of the influent during the steady phase of anammox activity. In addition, it is demonstrated that the status of the anammox bioreactor can be indicated by the alkalinity and pH value during the course of the experiment. The anammox bioreactor has shown potential for nitrogen removal in the leachate mixture. However, COD and total phosphorous in the leachate mixture need further treatment for removal efficiencies of COD and total phosphorous are not good in the anammox bioreactor.

  2. Anaerobic ammonium oxidation in a bioreactor treating slaughterhouse wastewater

    Directory of Open Access Journals (Sweden)

    V. Reginatto

    2005-12-01

    Full Text Available Ammonium oxidation was thought to be an exclusively aerobic process; however, as recently described in the literature, it is also possible under anaerobic conditions and this process was named ANAMMOX. This work describes the operation of a system consisting of a denitrifying reactor coupled to a nitrifying reactor used for removal of nitrogen from slaughterhouse wastewater. During operation of the denitrifying reactor an average nitrogen ammonium removal rate of 50 mg/Ld was observed. This biomass was used to seed a second reactor, operated in repeated fed batch mode, fed with synthetic medium specific to the growth of bacteria responsible for the ANAMMOX process. The nitrogen loading rate varied between 33 and 67 mgN/Ld and average nitrogen removal was 95% and 40%, respectively. Results of fluorescence in situ hybridization (FISH confirmed the presence of anammox-like microorganisms in the enriched biomass.

  3. Occurrence of Anaerobic Ammonium Oxidation in the Yangtze Estuary

    Science.gov (United States)

    Hou, L.

    2013-12-01

    Over the past several decades, a large quantity of reactive nitrogen has been transported into the Yangtze estuarine and coastal water, due to intense human activities in the Yangtze River Basin. At present, it annually receives a high load of anthropogenic inorganic nitrogen (about 1.1 × 1011 mol N) from increased agricultural activities, fish farming, and domestic and industrial wastewater discharge in the Yangtze River Basin, consequently leading to severe eutrophication and frequent occurrences of harmful algal blooms in the estuary and adjacent coastal areas. Hence, the microbial nitrogen transformations are of major concern in the Yangtze Estuary. Anaerobic ammonium oxidation (anammox) has been reported to play a significant role in the removal of reactive nitrogen in aquatic ecosystems. In this study, the occurrences of anammox bacteria and associated activity in the Yangtze Estuary were evidenced with molecular and isotope-tracing techniques. It is observed that the anammox bacteria at the study area mainly consisted of Candidatus Scalindua, Brocadia, Kuenenia. Salinity was found to be a key environmental factor controlling distribution and diversity of the anammox bacterial community at the estuarine ecosystem. Also, temperature and organic carbon had significant influences on anammox bacterial biodiversity. Q-PCR assays of anammox bacteria indicated that their abundance had a range of 2.63 ×106 - 9.48 ×107 copies g-1 dry sediment, with high spatiotemporal heterogeneity. The potential anammox activities measured in the present work varied between 0.94 - 6.61nmol N g-1 dry sediment h-1, which were related to temperature, nitrite and anammox bacterial abundance. On the basis of the 15N tracing experiments, the anammox process was estimated to contribute 6.6 - 12.9 % to the total nitrogen loss whereas the remainder was attributed to denitrification.

  4. Review:Anaerobic ammonium oxidation for treatment of ammonium-rich wastewaters

    Institute of Scientific and Technical Information of China (English)

    Lei ZHANG; Ping ZHENG; Chongojian TANG; Ren-cun JIN

    2008-01-01

    The concept of anaerobic ammonium oxidation (ANAMMOX) is presently of great interest.The functional bacteria belonging to the Planctomycete phylum and their metabolism are investigated by microbiologists.Meanwhile,the ANAMMOX is equally valuable in treatment of ammonium-rich wastewaters.Related processes including partial nitritation-ANAMMOX and completely autotrophic nitrogen removal over nitrite (CANON) have been developed,and lab-scale experiments proved that both processes were quite feasible in engineering with appropriate control.Successful full-scale practice in the Netherlands will ac-celerate application of the process in future.This review introduces the microbiology and more focuses on application of the ANAMMOX process.

  5. Anaerobic ammonium oxidation for advanced municipal wastewater treatment: is it feasible?

    Institute of Scientific and Technical Information of China (English)

    LI Jie; XIONG Bi-yong; ZHANG Shu-de; YANG Hong; ZHANG Jie

    2005-01-01

    Anaerobic ammonium oxidation(ANAMMOX) is a recently developed process to treat ammonia-rich wastewater. There were numerous articles about the new technology with focus on the ammonium-rich wastewater treatment, but few on advanced municipal wastewater treatment. The paper studied the anaerobic ammonium oxidation(ANAMMOX) process with a down flow anoxic biofilter for nitrogen removal from secondary clarifier effluent of municipal wastewater with low COD/N ratio. The results showed that ANAMMOX process is applicable to advanced wastewater treatment with normal temperature as well as ammonia-rich high temperature wastewater treatment. The results indicated that ammonia removal rate was improved by raising the nitrite concentration, and the reaction rate reached a climax at 118.4 mgN/L of the nitrite nitrogen concentration. If the concentration exceeds 118.4 mgN/L, the ANAMMOX process was significantly inhibited although the ANAMMOX bacteria still showed a relatively high reactivity. The data also indicated that the ratio of NO2- -N:NH4 + -N = 1.3:1 in the influent was appropriate for excellent nitrogen removal. The pH increased gradually along the ANAMMOX biofilter reactor. When the ANAMMOX reaction was ended, the pH was tend to calm. The data suggested that the pH could be used as an indicator to describe the course of ANAMMOX reaction.

  6. Nitrogen removal by autotrophic ammonium oxidizing bacteria enrichment under anaerobic conditions

    Directory of Open Access Journals (Sweden)

    Pongsak (Lek Noophan

    2008-07-01

    Full Text Available Sludge from an anoxic tank at the centralized wastewater treatment plant, Nong Khaem, Bangkok, Thailand, was inoculatedin an anaerobic sequencing batch reactor (ASBR. The optimal compositions and operating conditions of the stock of autotrophic ammonium oxidizing bacteria medium were determined. The process of oxidizing ammonium with bacteria under anaerobic conditions is often referred to as the Anammox process (NO2- to N2 gas, using NH4+ as the electron donor and NO2- as the electron acceptor. The startup period for the anammox culture took more than three months. With ammoniumand nitrite concentration ratios of 1:1.38 and 1:1.6, the nitrogen conversion rate zero order. Fluorescent in situ hybridization(FISH was used to identify specific autotrophic ammonium oxidizing bacteria (Nitrosomonas spp., Candidatus Brocadia anammoxidans, and Candidatus Kuenenia stuttgartiensis. Results from this work demonstrated a shift in the species of ammonium oxidizing bacteria from Nitrosomonas spp. to Candidati Brocadia anammoxidans and Kuenenia stuttgartiensis, with increased ammonium concentrations from 3 mM to 15 mM. Under NH4+:NO2- ratios of 1:1.38 and 1:1.6 the ammoniumoxidizing bacteria were able to remove both ammonium and nitrite simultaneously. The specific nitrogen removal rate of theanammox bacteria (Candidati Brocadia anammoxidans and Kuenenia stuttgartiensis was significantly higher than that of anaerobic ammonium oxidizing bacteria (Nitrosomonas spp.. Anaerobic ammonium oxidizing bacteria (Candidati Brocadia anammoxidans and Kuenenia stuttgartiensis are strict anaerobes.

  7. Nitrogen removal by autotrophic ammonium oxidizing bacteria enrichment under anaerobic conditions

    OpenAIRE

    Pongsak (Lek) Noophan; Chalermraj Wantawin; Siriporn Sripiboon; Sanya Sirivitayapakorn

    2008-01-01

    Sludge from an anoxic tank at the centralized wastewater treatment plant, Nong Khaem, Bangkok, Thailand, was inoculatedin an anaerobic sequencing batch reactor (ASBR). The optimal compositions and operating conditions of the stock of autotrophic ammonium oxidizing bacteria medium were determined. The process of oxidizing ammonium with bacteria under anaerobic conditions is often referred to as the Anammox process (NO2- to N2 gas, using NH4+ as the electron donor and NO2- as the electron accep...

  8. Effect of inorganic carbon on anaerobic ammonium oxidation enriched in sequencing batch reactor

    Institute of Scientific and Technical Information of China (English)

    Liao Dexiang; Li Xiaoming; Yang Qi; Zeng Guangming; Guo Liang; Yue Xiu

    2008-01-01

    The present lab-scale research reveals the enrichment of anaerobic ammonium oxidation microorganism from methanogenic anaerobic granular sludge and the effect of inorganic carbon (sodium bicarbonate) on anaerobic ammonium oxidation. The enrichment of anammox bacteria was carried out in a 7.0-L SBR and the effect of bicarbonate on anammox was conducted in a 3.0-L SBR. Research results , especially the biomass, showed first signs of anammox activity after 54 d cultivation with synthetic wastewater, when the pH was controlled between 7.5 and 8.3, the temperature was 35℃. The anammox activity increased as the influent bicarbonate concentration increased from 1.0 to 1.5 g/L and then, was inhibited as the bicarbonate concentration approached 2.0 g/L. However, the activity could be restored by the reduction of bicarbonate concentration to 1.0 g/L, as shown by rapid conversion of ammonium, and nitrite and nitrate production with normal stoichiometry. The optimization of the bicarbonate concentration in the reactor could increase the anammox rate up to 66.4 mgN/(L·d).

  9. Nitrous oxide production pathways in a partial nitritation-anammox reactor: Isotopic evidence for nitrous oxide production associated anaerobic ammonium oxidation?

    Science.gov (United States)

    Wunderlin, P.; Harris, E. J.; Joss, A.; Emmenegger, L.; Kipf, M.; Mohn, J.; Siegrist, H.

    2014-12-01

    Nitrous oxide (N2O) is a strong greenhouse gas and a major sink for stratospheric ozone. In biological wastewater treatment N2O can be produced via several pathways. This study investigates the dynamics of N2O emissions from a nitritation-anammox reactor, and links its interpretation to the nitrogen and oxygen isotopic signature of the emitted N2O. A 400-litre single-stage nitritation-anammox reactor was operated and continuously fed with digester liquid. The isotopic composition of N2O emissions was monitored online with quantum cascade laser absorption spectroscopy (QCLAS; Aerodyne Research, Inc.; Waechter et al., 2008). Dissolved ammonium and nitrate were monitored online (ISEmax, Endress + Hauser), while nitrite was measured with test strips (Nitrite-test 0-24mgN/l, Merck). Table 1. Summary of experiments conducted to understand N2O emissions Experimental conditions O2[mgO2/L] NO2-[mgN/L] NH4+[mgN/L] N2O/NH4+[%] Normal operation reactor. Our data reveal that N2O emissions increased when reactor operation was not ideal, for example when dissolved oxygen was too high (Table 1). SP measurements confirmed that these N2O peaks were due to enhanced nitrifier denitrification, generally related to nitrite build-up in the reactor (Figure 1; Table 1). Overall, process control via online N2O monitoring was confirmed to be an ideal method to detect imbalances in reactor operation and regulate aeration, to ensure optimal reactor conditions and minimise N2O emissions. ReferencesWaechter H. et al. (2008) Optics Express, 16: 9239-9244. Wunderlin, P et al. (2013) Environmental Science & Technology 47: 1339-1348.

  10. [Achievement of Sulfate-Reducing Anaerobic Ammonium Oxidation Reactor Started with Nitrate-Reducting Anaerobic Ammonium Oxidation].

    Science.gov (United States)

    Liu, Zheng-chuan; Yuan, Lin-jiang; Zhou, Guo-biao; Li, Jing

    2015-09-01

    The transformation of nitrite-reducing anaerobic ammonium oxidation to sulfate-reducing anaerobic ammonium oxidation in an UASB was performed and the changes in microbial community were studied. The result showed that the sulfate reducing anaerobic ammonium oxidation process was successfully accomplished after 177 days' operation. The removal rate of ammonium nitrogen and sulfate were up to 58. 9% and 15. 7%, the removing load of ammonium nitrogen and sulfate were 74. 3 mg.(L.d)-1 and 77. 5 mg.(L.d)-1 while concentration of ammonium nitrogen and sulfate of influent were 130 mg.(L.d)-1 and 500 mg.(L.d)-1, respectively. The lost nitrogen and sulphur was around 2 in molar ratio. The pH value of the effluent was lower than that of the influent. Instead of Candidatus brocadia in nitrite reducing anaerobic ammonium oxidation granular sludge, Bacillus benzoevorans became the dominant species in sulfate reducing anaerobic ammonium oxidation sludge. The dominant bacterium in the two kinds of anaerobic ammonium oxidation process is different. Our results imply that the two anaerobic ammonium oxidation processes are carried out by different kind of bacterium. PMID:26717697

  11. Nitrous oxide production pathways in a partial nitritation-anammox reactor: Isotopic evidence for nitrous oxide production associated anaerobic ammonium oxidation?

    Science.gov (United States)

    Wunderlin, P.; Harris, E. J.; Joss, A.; Emmenegger, L.; Kipf, M.; Mohn, J.; Siegrist, H.

    2014-12-01

    Nitrous oxide (N2O) is a strong greenhouse gas and a major sink for stratospheric ozone. In biological wastewater treatment N2O can be produced via several pathways. This study investigates the dynamics of N2O emissions from a nitritation-anammox reactor, and links its interpretation to the nitrogen and oxygen isotopic signature of the emitted N2O. A 400-litre single-stage nitritation-anammox reactor was operated and continuously fed with digester liquid. The isotopic composition of N2O emissions was monitored online with quantum cascade laser absorption spectroscopy (QCLAS; Aerodyne Research, Inc.; Waechter et al., 2008). Dissolved ammonium and nitrate were monitored online (ISEmax, Endress + Hauser), while nitrite was measured with test strips (Nitrite-test 0-24mgN/l, Merck). Table 1. Summary of experiments conducted to understand N2O emissions Experimental conditions O2[mgO2/L] NO2-[mgN/L] NH4+[mgN/L] N2O/NH4+[%] Normal operation <0.1 <0.5 10 0.6 Normal operation, high NH4+ <0.1 <0.5 100 6.1 High aeration 0.5 to 1.5 up to 50 10 and 50 4.9 NO2- addition (oxic) <0.1 <0.5 to 4 10 5.8 NO2- addition (anoxic) 0 <0.5 to 4 10 3.2 NH2OH addition <0.1 <0.5 10 2.5 Results showed that under normal operating conditions, the N2O isotopic site preference (SP = d15Nα - d15Nβ) was much higher than expected - up to 41‰ - strongly suggesting an unknown N2O production pathway, which is hypothesized to be mediated by anammox activity (Figure 1). A less likely explanation is that the SP of N2O was increased by partial N2O reduction by heterotrophic denitrification. Various experiments were conducted to further investigate N2O formation pathways in the reactor. Our data reveal that N2O emissions increased when reactor operation was not ideal, for example when dissolved oxygen was too high (Table 1). SP measurements confirmed that these N2O peaks were due to enhanced nitrifier denitrification, generally related to nitrite build-up in the reactor (Figure 1; Table 1). Overall

  12. Importance and controls of anaerobic ammonium oxidation influenced by riverbed geology

    Science.gov (United States)

    Lansdown, K.; McKew, B. A.; Whitby, C.; Heppell, C. M.; Dumbrell, A. J.; Binley, A.; Olde, L.; Trimmer, M.

    2016-05-01

    Rivers are an important global sink for excess bioavailable nitrogen: they convert approximately 40% of terrestrial N runoff per year (~47 Tg) to biologically unavailable N2 gas and return it to the atmosphere. At present, riverine N2 production is conceptualized and modelled as denitrification. Anaerobic ammonium oxidation, known as anammox, is an alternative pathway of N2 production important in marine environments, but its contribution to riverine N2 production is not well understood. Here we use in situ and laboratory measurements of anammox activity using 15N tracers and molecular analyses of microbial communities to evaluate anammox in clay-, sand- and chalk-dominated river beds in the Hampshire Avon catchment, UK during summer 2013. Abundance of the hzo gene, which encodes an enzyme central to anammox metabolism, varied across the contrasting geologies. Anammox rates were similar across geologies but contributed different proportions of N2 production because of variation in denitrification rates. In spite of requiring anoxic conditions, anammox, most likely coupled to partial nitrification, contributed up to 58% of in situ N2 production in oxic, permeable riverbeds. In contrast, denitrification dominated in low-permeability clay-bed rivers, where anammox contributes roughly 7% to the production of N2 gas. We conclude that anammox can represent an important nitrogen loss pathway in permeable river sediments.

  13. Single stage biological nitrogen removal by nitritation and anaerobic ammonium oxidation in biofilm systems.

    Science.gov (United States)

    Helmer, C; Tromm, C; Hippen, A; Rosenwinkel, K H; Seyfried, C F; Kunst, S

    2001-01-01

    In full scale wastewater treatment plants with at times considerable deficits in the nitrogen balances, it could hitherto not be sufficiently explained which reactions are the cause of the nitrogen losses and which micro-organisms participate in the process. The single stage conversion of ammonium into gaseous end-products--which is henceforth referred to as deammonification--occurs particularly frequently in biofilm systems. In the meantime, one has succeeded to establish the deammonification processes in a continuous flow moving-bed pilot plant. In batch tests with the biofilm covered carriers, it was possible for the first time to examine the nitrogen conversion at the intact biofilm. Depending on the dissolved oxygen (DO) concentration, two autotrophic nitrogen converting reactions in the biofilm could be proven: one nitritation process under aerobic conditions and one anaerobic ammonium oxidation. With the anaerobic ammonium oxidation, ammonium as electron donor was converted with nitrite as electron acceptor. The end-product of this reaction was N2. Ammonium and nitrite did react in a stoichiometrical ratio of 1:1.37, a ratio which has in the very same dimension been described for the ANAMMOX-process (1:1.31 +/- 0.06). Via the oxygen concentration in the surrounding medium, it was possible to control the ratio of nitritation and anaerobic ammonium oxidation in the nitrogen conversion of the biofilm. Both processes were evenly balanced at a DO concentration of 0.7 mg/l, so that it was possible to achieve a direct, almost complete elimination of ammonium without addition of nitrite. One part of the provided ammonium did participate in the nitritation, the other in the anaerobic ammonium oxidation. Through the aerobic ammonium oxidation into nitrite within the outer oxygen supplied layers of the biofilm, the reaction partner was produced for the anaerobic ammonium oxidation within the inner layers of the biofilm. PMID:11379106

  14. Anaerobic ammonium-oxidizing bacteria gain antibiotic resistance during long-term acclimatization.

    Science.gov (United States)

    Zhang, Zheng-Zhe; Zhang, Qian-Qian; Guo, Qiong; Chen, Qian-Qian; Jiang, Xiao-Yan; Jin, Ren-Cun

    2015-09-01

    Three broad-spectrum antibiotics, amoxicillin (AMX), florfenicol (FF) and sulfamethazine (SMZ), that inhibit bacteria via different target sites, were selected to evaluate the acute toxicity and long-term effects on anaerobic ammonium oxidation (anammox) granules. The specific anammox activity (SAA) levels reduced by approximately half within the first 3 days in the presence of antibiotics but no nitrite accumulation was observed in continuous-flow experiments. However, the SAA levels and heme c content gradually recovered as the antibiotic concentrations increased. Extracellular polymeric substances (EPS) analysis suggested that anaerobic ammonium-oxidizing bacteria gradually developed a better survival strategy during long-term acclimatization, which reduced the antibiotic stress via increased EPS secretion that provided a protective 'cocoon.' In terms of nitrogen removal efficiency, anammox granules could resist 60 mg-AMX L(-1), 10 mg-FF L(-1) and 100 mg-SMZ L(-1). This study supported the feasibility of using anammox granules to treat antibiotic-containing wastewater. PMID:26111629

  15. Performance of sulfate-dependent anaerobic ammo-nium oxidation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; ZHENG Ping; HE YuHui; JIN RenCun

    2009-01-01

    The performance of sulfate-dependent anaerobic ammonium oxidation was studied. The results showed that both SO42- and NH4+ were chemically stable under anaerobic conditions. They did not react with each other in the absence of biological catalyst (sludge). The anaerobic digested sludge cultivated in an anaerobic reactor for three years took on the ability of oxidizing ammonium with sulfate anaero-bically. The average reduction of sulfate and ammonium was 71.67 mg.L-1 and 56.82 mg.L-1 at high concentrations.The reaction between SO42- and NH4+ was difficult, though feasible, due to its low standard Gibbs free energy change. The experiment demonstrated that high substrate concentrations and low oxidation-reduction potential (ORP) may be favourable for the biological reaction.

  16. Performance of sulfate-dependent anaerobic ammonium oxidation

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The performance of sulfate-dependent anaerobic ammonium oxidation was studied.The results showed that both SO42-and NH4+ were chemically stable under anaerobic conditions.They did not react with each other in the absence of biological catalyst(sludge).The anaerobic digested sludge cultivated in an anaerobic reactor for three years took on the ability of oxidizing ammonium with sulfate anaero-bically.The average reduction of sulfate and ammonium was 71.67 mg.L-1 and 56.82 mg.L-1 at high concentrations.The reaction between SO42-and NH4+ was difficult,though feasible,due to its low standard Gibbs free energy change.The experiment demonstrated that high substrate concentrations and low oxidation-reduction potential(ORP) may be favourable for the biological reaction.

  17. Impact of free ammonia on anammox rates (anoxic ammonium oxidation) in a moving bed biofilm reactor.

    Science.gov (United States)

    Jaroszynski, L W; Cicek, N; Sparling, R; Oleszkiewicz, J A

    2012-06-01

    Using a bench scale moving bed bioreactor (MBBR), the effect of free ammonia (FA, NH(3), the un-ionized form of ammonium NH(4)(+)) concentration on anoxic ammonium oxidation (anammox) was evaluated based on the volumetric nitrogen removal rate (NRR). Although, a detailed microbial analysis was not conducted, the major NRR observed was assumed to be by anammox, based on the nitrogen conversion ratios of nitrite to ammonium and nitrate to ammonium. Since the concentration of free ammonia as a proportion of the total ammonia concentration is pH-dependent, the impact of changing the operating pH from 6.9 to 8.2, was investigated under constant nitrogen loading conditions during continuous reactor operation. Furthermore, the effect of sudden nitrogen load changes was investigated under constant pH conditions. Batch tests were conducted to determine the immediate response of the anammox consortium to shifts in pH and FA concentrations. It was found that FA was inhibiting NRR at concentrations exceeding 2 mg N L(-1). In the pH range 7-8, the decrease in anammox activity was independent of pH and related only to the concentration of FA. Nitrite concentrations of up to 120 mg N L(-1) did not negatively affect NRR for up to 3.5 h. It was concluded that a stable NRR in a moving bed biofilm reactor depended on maintaining FA concentrations below 2 mg N L(-1) when the pH was maintained between 7 and 8. PMID:22483855

  18. Temperature response of denitrification and anaerobic ammonium oxidation rates and microbial community structure in Arctic fjord sediments.

    Science.gov (United States)

    Canion, Andy; Overholt, Will A; Kostka, Joel E; Huettel, Markus; Lavik, Gaute; Kuypers, Marcel M M

    2014-10-01

    The temperature dependency of denitrification and anaerobic ammonium oxidation (anammox) rates from Arctic fjord sediments was investigated in a temperature gradient block incubator for temperatures ranging from -1 to 40°C. Community structure in intact sediments and slurry incubations was determined using Illumina SSU rRNA gene sequencing. The optimal temperature (Topt ) for denitrification was 25-27°C, whereas anammox rates were optimal at 12-17°C. Both denitrification and anammox exhibited temperature responses consistent with a psychrophilic community, but anammox bacteria may be more specialized for psychrophilic activity. Long-term (1-2 months) warming experiments indicated that temperature increases of 5-10°C above in situ had little effect on the microbial community structure or the temperature response of denitrification and anammox. Increases of 25°C shifted denitrification temperature responses to mesophilic with concurrent community shifts, and anammox activity was eliminated above 25°C. Additions of low molecular weight organic substrates (acetate and lactate) caused increases in denitrification rates, corroborating the hypothesis that the supply of organic substrates is a more dominant control of respiration rates than low temperature. These results suggest that climate-related changes in sinking particulate flux will likely alter rates of N removal more rapidly than warming. PMID:25115991

  19. Community composition and activity of anaerobic ammonium oxidation bacteria in the rhizosphere of salt-marsh grass Spartina alterniflora.

    Science.gov (United States)

    Zheng, Yanling; Hou, Lijun; Liu, Min; Yin, Guoyu; Gao, Juan; Jiang, Xiaofen; Lin, Xianbiao; Li, Xiaofei; Yu, Chendi; Wang, Rong

    2016-09-01

    Anaerobic ammonium oxidation (anammox) as an important nitrogen removal pathway has been investigated in intertidal marshes. However, the rhizosphere-driven anammox process in these ecosystems is largely overlooked so far. In this study, the community dynamics and activities of anammox bacteria in the rhizosphere and non-rhizosphere sediments of salt-marsh grass Spartina alterniflora (a widely distributed plant in estuaries and intertidal ecosystems) were investigated using clone library analysis, quantitative PCR assay, and isotope-tracing technique. Phylogenetic analysis showed that anammox bacterial diversity was higher in the non-rhizosphere sediments (Scalindua and Kuenenia) compared with the rhizosphere zone (only Scalindua genus). Higher abundance of anammox bacteria was detected in the rhizosphere (6.46 × 10(6)-1.56 × 10(7) copies g(-1)), which was about 1.5-fold higher in comparison with that in the non-rhizosphere zone (4.22 × 10(6)-1.12 × 10(7) copies g(-1)). Nitrogen isotope-tracing experiments indicated that the anammox process in the rhizosphere contributed to 12-14 % N2 generation with rates of 0.43-1.58 nmol N g(-1) h(-1), while anammox activity in the non-rhizosphere zone contributed to only 4-7 % N2 production with significantly lower activities (0.28-0.83 nmol N g(-1) h(-1)). Overall, we propose that the rhizosphere microenvironment in intertidal marshes might provide a favorable niche for anammox bacteria and thus plays an important role in nitrogen cycling. PMID:27225476

  20. Batch culture enrichment of ANAMMOX populations from anaerobic and aerobic seed cultures.

    Science.gov (United States)

    Suneethi, S; Joseph, Kurian

    2011-01-01

    Discharge of nitrate and ammonia rich wastewaters into the natural waters encourage eutrophication, and contribute to aquatic toxicity. Anaerobic ammonium oxidation process (ANAMMOX) is a novel biological nitrogen removal alternative to nitrification-denitrification, that removes ammonia using nitrite as the electron acceptor. The feasibility of enriching the ANAMMOX bacteria from the anaerobic digester sludge of a biomethanation plant treating vegetable waste and aerobic sludge from an activated sludge process treating domestic sewage is reported in this paper. ANAMMOX bacterial activity was monitored and established in terms of nitrogen transformations to ammonia, nitrite and nitrate along with formation of hydrazine and hydroxylamine. PMID:20729077

  1. Biological nitrogen removal in one step by nitritation and anaerobic oxidation of ammonia in biofilms; Einstufige biologische Stickstoffelimination durch Nitritation und anaerobe Ammonium-Oxidation im Biofilm

    Energy Technology Data Exchange (ETDEWEB)

    Helmer, C.; Tromm, C.; Hippen, A.; Rosenwinkel, K.H.; Seyfried, C.F.; Kunst, S. [Hannover Univ. (Germany). Inst. fuer Siedlungswasserwirtschaft und Abfalltechnik

    1999-07-01

    For biological treatment of high nitrogenous wastewaters with low C/N ratio autotrophic microorganisms which are able to convert ammonium directly into nitrogen gas are especially interesting. It is exceptionally difficult to verify their presence and importance in mixed populations of full scale wastewater treatment plants. So it could not be clarified finally up to now which basic microbial reactions lead to single stage complete nitrogen removal, here called deammonification, in the nitrification step (biological contactor) of the leachate treatment plant in Mechernich. It succeeded meanwhile to establish the process of deammonification in a continuous flow moving-bed pilot plant. In batch experiments which biomass-covered carriers nitrogen conversions could become investigated at the intact biofilm for the first time. Two autotrophic nitrogen conversion reactions could be proved in the biofilm depending on dissolved oxygen (DO) concentration: A nitritation under aerobic conditions and an anaerobic ammonium oxidation. For the anaerobic ammonium oxidation nitrite was used as electron acceptor with ammonium as electron donor. N{sub 2} was the end product of the reaction. The ratio of ammonium conversion to nitrite conversion was 1:1,37, which was described in the same range for the ANAMMOX-process (1:1,31{+-}0,06). Nitrate could not be used as electron acceptor. Nitrite had to be added to the experiment to obtain oxygen independent oxidation of ammonium. The parts of nitritation and anaerobic ammonium conversion in nitrogen conversion could be controlled by the DO concentration. At a DO concentration of 0.7 mg/l both processes were balanced, so that a direct almost complete elimination of ammonium was possible without any dosage of nitrite. The added ammonium was partially oxidised to nitrite and partially oxidised anaerobically. The aerobic ammonium oxidation to nitrite in the outer oxygen supplied biofilm layers produced the reactant for the anaerobic ammonium

  2. ANAMMOX process start up and stabilization with an anaerobic seed in Anaerobic Membrane Bioreactor (AnMBR).

    Science.gov (United States)

    Suneethi, S; Joseph, Kurian

    2011-10-01

    ANaerobic AMMonium OXidation (ANAMMOX) process, an advanced biological nitrogen removal alternative to traditional nitrification--denitrification removes ammonia using nitrite as the electron acceptor without oxygen. The feasibility of enriching anammox bacteria from anaerobic seed culture to start up an Anaerobic Membrane Bioreactor (AnMBR) for N-removal is reported in this paper. The Anammox activity was established in the AnMBR with anaerobic digester seed culture from a Sewage Treatment Plant in batch mode with recirculation followed by semi continuous process and continuous modes of operation. The AnMBR performance under varying Nitrogen Loading Rates (NLR) and HRTs is reported for a year, in terms of nitrogen transformations to ammoniacal nitrogen, nitrite and nitrate along with hydrazine and hydroxylamine. Interestingly ANAMMOX process was evident from simultaneous Amm-N and nitrite reduction, consistent nitrate production, hydrazine and hydroxylamine presence, notable organic load reduction and bicarbonate consumption. PMID:21775136

  3. The integration of methanogenesis with denitrification and anaerobic ammonium oxidation in an expanded granular sludge bed reactor

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The integration of methanogenesis with denitrification and anaerobic ammonium oxidation(ANAMMOX) was studied in an expanded granular sludge bed(EGSB) reactor in this work. Experimental results from the continuous treatment of wastewater with nitrite and ammonium, which lasted for 107 days, demonstrated that wastewater with high nitrite and ammonium could be anaerobically treated in an expanded granular sludge bed reactor. More than 91% to 97% of COD were removed at up to about 3.9 g COD/(L@d) of COD volumetric loading rate. More than 97% to 100% of nitrite was denitrified at up to about 0.8g NO2-N/(L@d), which is 16 times higher than that in a conventional activated sludge system with nitrification/denitrification(0.05g N/((L@d). No dissimilatory reduction of nitrite to ammonium occurred in the process. However, maximum of about 40% ammonium was found to be lost. Batch tests of 15 days with sludge from the reactor showed that 100% of nitrite was denitrified completely, and about 3% of ammonium was removed when only ammonium (34.3 mg/L) and nitrite(34.3 mg/L) were added into the sludge suspension medium. Furthermore, about 15% of ammonium amounts were lost with organic COD addition. It suggested that the methanogenesis in the system could enhance ANAMMOX because of intermediate hydrogen produced during methanogenesis.

  4. Concurrence of Anaerobic Ammonium Oxidation and Organotrophic Denitrification in Presence of p-Cresol.

    Science.gov (United States)

    González-Blanco, G; Cervantes, F J; Beristain-Cardoso, R; Gómez, J

    2015-08-01

    This study was carried out to evaluate the capacity of anaerobic granular sludge for oxidizing ammonium and p-cresol with nitrate as terminal electron acceptor. Kinetics for the anaerobic oxidation of ammonium and p-cresol is described in this paper. The phenolic compound was very efficiently consumed, achieving 65 % of mineralization. Ammonium and nitrate were also consumed at 83 and 92 %, respectively, being the main product N2. Anaerobic ammonium oxidation was promoted owing to accumulation of nitrite, and it allowed the synergy of anaerobic ammonium oxidation and organotrophic denitrification for the simultaneous removal of ammonium, nitrate, and p-cresol. A carbonaceous intermediate partially identified was transiently accumulated, and it transitorily truncated the respiratory process of denitrification. These experimental results might be considered for defining strategies in order to remove nitrate, ammonium, and phenolic compounds from wastewaters. PMID:26062920

  5. Identification of a denitrifying bacterium and verification of its anaerobic ammonium oxidation ability

    Institute of Scientific and Technical Information of China (English)

    HU; Baolan; ZHENG; Ping; LI; Jinye; XU; Xiangyang; JIN; Rencun

    2006-01-01

    A strain D3 of denitrifying bacterium was isolated from an anammox reactor, and identified as Pseudomonas mendocina based on the morphological and physiological assay, Vitek test,Biolog test, (G+C) mol% content, and 16S rDNA phylogenetic analysis. As a typical denitrifying bactration of 88.5 mg N/L. The optimal pH and growth temperature were 7.84 and 34.9℃, respectively.Strain D3 was able to oxidize ammonia under anaerobic condition. The maximum nitrate and ammoof ammonia to nitrate was 1:1.91. Electron microscopic observation revealed peculiar cell inclusions in strain D3. Because of its relation to anammox activity, strain D3 was presumed to be anammoxosome.The present investigation proved that denitrifying bacteria have the anammox ability, and the results have engorged the range of anammox populations.

  6. Research progress of Anammox-denitrification coupling start up and Influencing Factors

    Institute of Scientific and Technical Information of China (English)

    GUO Pi-jian

    2014-01-01

    Since anammox can simultaneously remove ammonia and nitrite nitrogen,And low cost,have been researched by many scholars,Its high ammonia wastewater treatment has great application value. However, high concentrations of organic carbon on anaerobic ammonium oxidation significantly inhibited. How to achieve anaerobic ammonium oxidation and denitrification coupling, is now a focus of research in the training process, anammox bacteria and denitrifying bacteria on pH, organic matter with different requirements, this paper summarizes the anammox and denitrification startup method and pH, organic matter on anaerobic ammonia oxidation and denitrification coupling and explore control strategies for anaerobic ammonium oxidation and denitrification coupling recommendations.

  7. Activity, Microenvironments, and Community Structure of Aerobic and Anaerobic Ammonium Oxidizing Prokaryotes in Estuarine Sediment (Randers Fjord, DK)

    DEFF Research Database (Denmark)

    Schramm, Andreas; Revsbech, Niels Peter; Dalsgaard, Tage;

    2006-01-01

    ACTIVITY, MICROENVIRONMENTS, AND COMMUNITY STRUCTURE OF AEROBIC AND ANAEROBIC AMMONIUM OXIDIZING PROKARYOTES IN ESTUARINE SEDIMENT (RANDERS FJORD, DK) A. Schramm 1, N.P. Revsbech 1, T. Dalsgaard 2, E. Piña-Ochoa 3, J. de la Torré 4, D.A. Stahl 4, N. Risgaard-Petersen 2 1 Department of Biological...

  8. Rates of N2 production and diversity and abundance of functional genes associated with denitrification and anaerobic ammonium oxidation in the sediment of the Amundsen Sea Polynya, Antarctica

    Science.gov (United States)

    Choi, Ayeon; Cho, Hyeyoun; Kim, Sung-Han; Thamdrup, Bo; Lee, SangHoon; Hyun, Jung-Ho

    2016-01-01

    A combination of molecular microbiological analyses and metabolic rate measurements was conducted to elucidate the diversity and abundance of denitrifying and anaerobic ammonium oxidation (anammox) bacteria and the nitrogen gas (N2) production rates in sediment underlying the highly productive polynya (Stns. 10 and 17) and the sea-ice zone on the outer shelf (Stn. 83) of the Amundsen Sea, Antarctica. Despite the high water column productivity, the N2 production rates by denitrification (0.04-0.31 nmol N cm-3sed. h-1) and anammox (0.13-0.26 nmol N cm-3 sed. h-1) were lower than those measured in other polar regions. In contrast, gene copy number (106-107 copies cm-3 of nirS and nosZ genes targeting denitirifiers and 105-107 copies cm-3 of 16S rRNA genes related to anammox bacteria) of the two bacterial groups at Stn. 17 was similar compared to those of other organic-rich environments. The majority of the nirS sequences were affiliated with Gammaproteobacteria (54% and 61% of the total nirS gene at Stns. 17 and 83, respectively), which were closely related to Pseudomonas aeruginosa. Most nosZ sequences (92% and 72% of the total nosZ genes at Stns. 17 and 83, respectively) were related to the Alphaproteobacteria, which were closely related to Ruegeria pomeroyi and Roseobacter denitrificans. Most (98%) of the sequences related to anammox bacteria were affiliated with Candidatus Scalindua at Stn. 17. Consequently, despite the low metabolic activity, the abundance and composition of most denitrifying and anammox bacteria detected from the ASP were similar to those reported from a variety of marine environments. Our results further imply that increased labile organic matter production resulting from a shift of the phytoplankton community from Phaeocystis to diatoms in response to rapid melting of sea ice stimulates metabolic activities of the denitrifying and anammox bacteria, thereby enhancing the N removal process in the ASP.

  9. The role of paraffin oil on the interaction between denitrifying anaerobic methane oxidation and Anammox processes.

    Science.gov (United States)

    Fu, Liang; Ding, Zhao-Wei; Ding, Jing; Zhang, Fang; Zeng, Raymond J

    2015-10-01

    Methane is sparingly soluble in water, resulting in a slow reaction rate in the denitrifying anaerobic methane oxidation (DAMO) process. The slow rate limits the feasibility of research to examine the interaction between the DAMO and the anaerobic ammonium oxidation (Anammox) process. In this study, optimized 5 % (v/v) paraffin oil was added as a second liquid phase to improve methane solubility in a reactor containing DAMO and Anammox microbes. After just addition, methane solubility was found to increase by 25 % and DAMO activity was enhanced. After a 100-day cultivation, the paraffin reactor showed almost two times higher consumption rates of NO3 (-) (0.2268 mmol/day) and NH4 (+) (0.1403 mmol/day), compared to the control reactor without paraffin oil. The microbes tended to distribute in the oil-water interface. The quantitative (q) PCR result showed the abundance of gene copies of DAMO archaea, DAMO bacteria, and Anammox bacteria in the paraffin reactor were higher than those in the control reactor after 1 month. Fluorescence in situ hybridization revealed that the percentages of the three microbes were 55.5 and 77.6 % in the control and paraffin reactors after 100 days, respectively. A simple model of mass balance was developed to describe the interactions between DAMO and Anammox microbes and validate the activity results. A mechanism was proposed to describe the possible way that paraffin oil enhanced DAMO activity. It is quite clear that paraffin oil enhances not only DAMO activity but also Anammox activity via the interaction between them; both NO3 (-) and NH4 (+) consumption rates were about two times those of the control. PMID:26036704

  10. Evaluation of granular anaerobic ammonium oxidation process for the disposal of pre-treated swine manure

    Directory of Open Access Journals (Sweden)

    Shou-Qing Ni

    2014-04-01

    Full Text Available With rising environmental concerns on potable water safety and eutrophication, increased media attention and tighter environmental regulations, managing animal waste in an environmentally responsible and economically feasible way can be a challenge. In this study, the possibility of using granular anammox process for ammonia removal from swine waste treatment water was investigated. A rapid decrease of NO2−–N and NH4+–N was observed during incubation with wastewater from an activated sludge deodorization reactor and anaerobic digestion-partial oxidation treatment process treating swine manure and its corresponding control artificial wastewaters. Ammonium removal dropped from 98.0 ± 0.6% to 66.9 ± 2.7% and nearly absent when the organic load in the feeding increased from 232 mg COD/L to 1160 mg COD/L and 2320 mg COD/L. The presence of organic carbon had limited effect on nitrite and total nitrogen removal. At a COD to N ratio of 0.9, COD inhibitory organic load threshold concentration was 727 mg COD/L. Mass balance indicated that denitrifiers played an important role in nitrite, nitrate and organic carbon removal. These results demonstrated that anammox system had the potential to effectively treat swine manure that can achieve high nitrogen standards at reduced costs.

  11. A laboratory investigation of interactions between denitrifying anaerobic methane oxidation (DAMO) and anammox processes in anoxic environments

    Science.gov (United States)

    Hu, Shihu; Zeng, Raymond J.; Haroon, Mohamed F.; Keller, Jurg; Lant, Paul A.; Tyson, Gene W.; Yuan, Zhiguo

    2015-03-01

    This study investigates interactions between recently identified denitrifying anaerobic methane oxidation (DAMO) and anaerobic ammonium oxidation (anammox) processes in controlled anoxic laboratory reactors. Two reactors were seeded with the same inocula containing DAMO organisms Candidatus Methanoperedens nitroreducens and Candidatus Methylomirabilis oxyfera, and anammox organism Candidatus Kuenenia stuttgartiensis. Both were fed with ammonium and methane, but one was also fed with nitrate and the other with nitrite, providing anoxic environments with different electron acceptors. After steady state reached in several months, the DAMO process became solely/primarily responsible for nitrate reduction while the anammox process became solely responsible for nitrite reduction in both reactors. 16S rRNA gene amplicon sequencing showed that the nitrate-driven DAMO organism M. nitroreducens dominated both the nitrate-fed (~70%) and the nitrite-fed (~26%) reactors, while the nitrite-driven DAMO organism M. oxyfera disappeared in both communities. The elimination of M. oxyfera from both reactors was likely the results of this organism being outcompeted by anammox bacteria for nitrite. K. stuttgartiensis was detected at relatively low levels (1-3%) in both reactors.

  12. The inhibition effects of salt on Anammox process:A review

    Institute of Scientific and Technical Information of China (English)

    QI Pan-qing

    2016-01-01

    Anaerobic ammonium oxidation was a novel biological nitrogen elimination process and attached more and more attention owing to its effectivity and economic saving. But, many kinds of factor especially salinity could affect the activity of Anammox bacteria which had some disadvantages to the application of Anammox process. In this article, a short review about the effects of salinity on Anammox bacteria was summarized and some advices were proposed to the research and the application of Anammox process in the future.

  13. Faster autotrophic growth of anaerobic ammonium-oxidizing microorganisms in presence of nitrite, using inocula from Colombia

    Directory of Open Access Journals (Sweden)

    Jaime Sanchez

    2014-06-01

    Full Text Available Título en español: Crecimiento rápido autotrófico de microorganismos anaerobios oxidadores de amonio en presencia de nitrito, usando inóculos de ColombiaShort Title: Growth from Colombian inoculated anammoxSummary: Anammox is a nitrite dependent process, catalyzed by bacteria of the order Brocadiales. Anammox bacteria oxidize ammonia under anoxic conditions, with nitrite as electron acceptor producing dinitrogen gas. Here, we demonstrated the presence of anammox bacteria by enriched them in a SBR reactor, with anaerobic samples taken from de bottom of a pond used in primary wastewater treatment. The enrichment reached nitrogen (N removal rates of nearly 1.92kg N/m3/day. (The stoichiometry of the reaction matched previous anammox studies. The enriched bacterial communities were analyzed by Fluorescence In situ Hybridization (FISH, and showed nearly a 90% of enrichment at the end of the experiment (day 90. As far as we know, this is the first time that the anammox bacteria were enriched using Colombian inocula. The enrichment was achieved in relatively short time with high yields and has an excellent potential for application in wastewater treatment opening the opportunity to treat nitrogen-rich effluents by partial nitritation and anammox, thereby decreasing operational costs with respect to aeration (nitrification and addition of organic electron donor (heterotrophic denitrification. This more sustainable treatment is a good alternative to control nutrient pollution in water bodies in tropical countries.Key words: nitrogen cycle; advanced treatment; anammox;  nitritation; nitratation; denitrification.Resumen: La oxidación anaerobia del amonio (anammox, es un proceso nitrito dependiente, catalizado por bacterias del filo planctomicetes. Estas bacterias oxidan el amonio en ausencia de oxígeno, con nitrito como aceptor de electrones produciendo nitrógeno molecular. En Colombia, demostramos la presencia de estas bacterias mediante el

  14. Anaerobic ammonium oxidation, denitrification and dissimilatory nitrate reduction to ammonium in the East China Sea sediment

    Directory of Open Access Journals (Sweden)

    G. D. Song

    2013-03-01

    Full Text Available Benthic nitrogen transformation pathways were investigated in the sediment of the East China Sea in June of 2010 using the 15N isotope pairing technique. Slurry incubations indicated that denitrification, anammox and dissimilatory nitrate reduction to ammonium (DNRA as well as nitrate release by nitrate storing organisms occurred in the East China Sea sediments. These four processes did not exist independently, the nitrate release therefore diluted the 15N labeling fraction of NO3−, a part of the 15NH4+ derived from DNRA also formed 30N2 via anammox. Therefore current methods of rate calculations led to over and underestimations of anammox and denitrification respectively. Following the procedure outlined in Thampdrup and Dalsgaard (2002, denitrification rates were slightly underestimated by on average 6% without regard to the effect of nitrate release, while this underestimation could be counteracted by the presence of DNRA. On the contrary, anammox rates calculated from 15NO3− experiment were significantly overestimated by 42% without considering nitrate release. In our study this overestimation could only be compensated 14% by taking DNRA into consideration. In a parallel experiment amended with 15NH4+ + 14NO3−, anammox rates were not significantly influenced by DNRA due to the high background of 15NH4+ addition. Excluding measurements in which bioirrigation was present, integrated denitrification rates decreased from 10 to 4 mmol N m−2 d−1 with water depth, while integrated anammox rates increased from 1.5 to 4.0 mmol N m−2 d−1. Consequently, the relative contribution of anammox to the total N-loss increased from 13% at the shallowest site near the Changjiang estuary to 50% at the deepest site on the outer shelf. This study represents the first time in which anammox has been demonstrated to play a significant role in benthic nitrogen cycling in the East China Sea sediment, especially on the outer shelf. N

  15. Importance of the operating pH in maintaining the stability of anoxic ammonium oxidation (anammox) activity in moving bed biofilm reactors.

    Science.gov (United States)

    Jaroszynski, L W; Cicek, N; Sparling, R; Oleszkiewicz, J A

    2011-07-01

    Two bench-scale parallel moving bed biofilm reactors (MBBR) were operated to assess pH-associated anammox activity changes during long term treatment of anaerobically digested sludge centrate pre-treated in a suspended growth partial nitrification reactor. The pH was maintained at 6.5 in reactor R1, while it was allowed to vary naturally between 7.5 and 8.1 in reactor R2. At high nitrogen loads reactor R2 had a 61% lower volumetric specific nitrogen removal rate than reactor R1. The low pH and the associated low free ammonia (FA) concentrations were found to be critical to stable anammox activity in the MBBR. Nitrite enhanced the nitrogen removal rate in the conditions of low pH, all the way up to the investigated level of 50mg NO(2)-N/L. At low FA levels nitrite concentrations up to 250 mg NO(2)-N/L did not cause inactivation of anammox consortia over a 2-days exposure time. PMID:21565492

  16. Advances in Studies of Anaerobic Ammonium Oxidation in the Marine Environment%海洋环境中的厌氧铵氧化研究进展

    Institute of Scientific and Technical Information of China (English)

    宋国栋; 刘素美

    2012-01-01

    As a new pathway to remove fixed nitrogen from marine ecosystem, anaerobic ammonium oxidation (anammox) widely occurs in various marine environments including the oxygen minimum zones, sediment, sea ice, even the deep-sea hydrothermal vents. Anammox is a key pathway for accurately estimating nitrogen budget and plays a significant role in the marine nitrogen cycle, which has an important impact on the global climate change. The history of anammox study is discussed. In addition, the distribution of anammox rates in oceanic OMZs and sediments and its significance is also discussed. The major environmental factors affecting the anammox rate are also summarized, including temperature, oxygen, sulfide, NO~/NO~,NH~ and organic matter. Finally, the problems and challenges in present and future studies are suggested as follows : the relative contribution of ana- mmox and denitrification in nitrogen loss in the OMZs; anammox in coastal hypoxic waters; further study of anam- mox in continental shelf and deep oceanic sediments; reevaluation of marine nitrogen budget.%海洋环境中的厌氧铵氧化过程作为实现固定态氮从海洋生态系统中移除的一个新途径,广泛地存在于各种海洋环境中,包括永久性缺氧水体、沉积物、海冰甚至海底热液,是海洋氮循环过程中一个非常重要的环节。开展海洋环境中厌氧铵氧化过程的研究可以更好地量化海洋氮循环过程中的收支,而这一收支在很大程度上影响着全球的气候变化。介绍了海洋环境中厌氧铵氧化过程研究历史,并分别讨论了在大洋缺氧水体和沉积物中厌氧铵氧化速率的分布情况,同时还总结了海洋环境因子如温度、氧气、硫化氢、NO3-/NO2-、NH4+以及有机物等对厌氧铵氧化的影响。最后探讨了该领域研究中所存在的问题并指出了亟待开展的工作:特定大洋缺氧水体中厌氧铵氧化与反硝化的争议以及近岸缺氧水体中厌氧铵

  17. Metabolic characteristics of anaerobic ammonium oxidizing bacteria with organic matters%有机物作用的厌氧氨氧化菌代谢特性研究进展

    Institute of Scientific and Technical Information of China (English)

    孙佳晶; 张蕾; 张超; 陈晓波

    2012-01-01

    厌氧氨氧化(Anammox)工艺是近年来废水生物脱氮领域的新技术,非常适合于处理含有机物的废水。本文介绍了厌氧氨氧化工艺的特点,详细介绍了有机物对厌氧氨氧化菌的抑制和促进机制。有机物对厌氧氨氧化菌的抑制主要来自两个方面:一是有机物促进异养菌反硝化菌的大量繁殖形成基质竞争抑制;二是废水中的醇类、抗生素等有毒有害有机物会对厌氧氨氧化菌产生毒性抑制。有机物对厌氧氨氧化菌代谢的促进作用也有两种:一是特定的有机物可作为能源被厌氧氨氧化菌利用,促进厌氧氨氧化菌的代谢;二是通过控制废水处理系统中的碳氮比,使厌氧氨氧化菌和反硝化菌在废水处理系统中协同互生。最后指出开发有毒有机废水预处理、驯化厌氧氨氧化污泥、菌种流加等是解决问题的途径。%Anaerobic ammonium oxidation(Anammox),a new biological nitrogen removal process in wastewater treatment,is very suitable for the treatment of wastewater containing organic matters.This paper introduces the characteristics of anaerobic ammonium oxidation process,especially the inhibitive and stimulative mechanisms of organic matters to the bacteria.Two mechanisms are attributed to organic matters induced inhibition,one is heterotrophic denitrifying bacteria promoted by organic matters can compete with anammox bacteria for substrates;the other one is that alcohols,antibiotics and other toxic organics in wastewater leads to toxic inhibition to anaerobic ammonium oxidation bacteria.The stimulation of organic matters to anaerobic ammonium oxidation bacteria also can be explained in two aspects:one is that certain organic matters can be used by anaerobic ammonium oxidation bacteria as energy source,and thus enhance their metabolism;the other is anaerobic ammonium oxidation bacteria and denitrifying bacteria can form symbiote with proper C:N ratio.The pretreatment of

  18. Enhanced ammonia removal at room temperature by pH controlled partial nitrification and subsequent anaerobic ammonium oxidation.

    Science.gov (United States)

    Durán, U; del Val Río, A; Campos, J L; Mosquera-Corral, A; Méndez, R

    2014-01-01

    The Anammox-based processes are suitable for the treatment of wastewaters characterized by a low carbon to nitrogen (C/N) ratio. The application of the Anammox process requires the availability of an effluent with a NO2- -N/NH4+ -N ratio composition around 1 g g-1, which involves the necessity of a previous step where the partial nitrification is performed. In this step, the inhibition of the nitrite-oxidizing bacteria (NOB) is crucial. In the present work, a combined partial nitrification-ANaerobic AMmonia OXidation (Anammox) two-units system operated at room temperature (20 degreeC) has been tested for the nitrogen removal of pre-treated pig slurry. To achieve the successful partial nitrification and inhibit the NOB activity, different ammonium/inorganic carbon (NH4+/IC) ratios were assayed from 1.19 to 0.82g NH4+-Ng-1 HCO3-C. This procedure provoked a decrease of the pH value to 6.0 to regulate the inhibitory effect over ammonia-oxidizing bacteria caused by free ammonia. Simultaneously, the NOB experienced the inhibitory effect of free nitrous acid which avoided the presence of nitrate in the effluent. The NH4+/IC ratio which allowed the obtaining of the desired effluent composition (50% of both ammonium and nitrite) was 0.82 +/- 0.02 g NH4+-N g-1 HCO3- -C. The Anammox reactor was fed with the effluent of the partial nitrification unit containing a NO2 -N/NH4+ -N ratio of 1 g g-1' where a nitrogen loading rate of 0.1 g N L-1 d-1 was efficiently removed. PMID:24600878

  19. Long-term performance and microbial ecology of a two-stage PN-ANAMMOX process treating mature landfill leachate.

    Science.gov (United States)

    Li, Huosheng; Zhou, Shaoqi; Ma, Weihao; Huang, Pengfei; Huang, Guotao; Qin, Yujie; Xu, Bin; Ouyang, Hai

    2014-05-01

    Long-term performance of a two-stage partial nitritation (PN)-anaerobic ammonium oxidation (ANAMMOX) process treating mature landfill leachate was investigated. Stable partial nitritation performance was achieved in a sequencing batch reactor (SBR) using endpoint pH control, providing an effluent with a ratio of NO2(-)-N/NH4(+)-N at 1.23 ± 0.23. High rate nitrogen removal over 4 kg N/m(3)/d was observed in the ANAMMOX reactor in the first three months. However, during long-term operation, the ANAMMOX reactor can only stably operate under nitrogen load of 1 kg N/m(3)/d, with 85 ± 1% of nitrogen removal. The ammonium oxidizing bacteria (AOB) in the PN-SBR were mainly affiliated to Nitrosomonas sp. IWT514, Nitrosomonas eutropha and Nitrosomonas eutropha, the anaerobic ammonium oxidizing bacteria (AnAOB) in the ANAMMOX reactor were mainly affiliated to Kuenenia stuttgartiensis. PMID:24681301

  20. [Application and obstacles of ANAMMOX process].

    Science.gov (United States)

    Jin Rencun; Zhang, Zhengzhe; Ji, Yuxin; Chen, Hui; Guo, Qiong; Zhou, Yuhuang; Wu, Conghui; Jin, Rencun

    2014-12-01

    Anaerobic ammonium oxidation (ANAMMOX), as its essential advantages of high efficiency and low cost, is a promising novel biological nitrogen elimination process with attractive application prospects. Over the past two decades, many processes based on the ANAMMOX reaction have been continuously studied and applied to practical engineering, with the perspective of reaching 100 full-scale installations in operation worldwide by 2014. Our review summarizes various forms of ANAMMOX processes, including partial nitritation-ANAMMOX, completely autotrophic nitrogen removal over nitrite, oxygen limited autotrophic nitrification and denitrification, denitrifying ammonium oxidation, aerobic deammonification, simultaneous partial nitrification, ANAMMOX and denitrification, single-stage nitrogen removal using ANAMMOX and partial nitritation. We also compare the operating conditions for one-stage and two-stage processes and summarize the obstacles and countermeasures in engineering application of ANAMMOX systems, such as moving bed biofilm reactor, sequencing batch reactor and granular sludge reactor. Finally, we discuss the future research and application direction, which should focus on the optimization of operating conditions and applicability of the process to the actual wastewater, especially on automated control and the impact of special wastewater composition on process performance. PMID:26016370

  1. Massive nitrogen loss from the Benguela upwelling system through anaerobic ammonium oxidation RID B-8834-2011

    DEFF Research Database (Denmark)

    Kuypers, MMM; Lavik, G.; Woebken, D.;

    2005-01-01

    the world ocean, the Benguela upwelling system. Our in situ experiments indicate that nitrate is not directly converted to N-2 by heterotrophic denitrification in the suboxic zone. In the Benguela system, nutrient profiles, anammox rates, abundances of anammox cells, and specific biomarker lipids...

  2. 舟山群岛海域沉积物厌氧氨氧化细菌多样性%Diversity of anaerobic ammonium oxidizing bacteria in marine sediments from the Zhoushan Islands

    Institute of Scientific and Technical Information of China (English)

    张东声; 刘镇盛; 张海峰; 王小谷; 王春生

    2015-01-01

    Anaerobic ammonium oxidation ( anammox) is an important process regulating the balance of marine nitrogen and ecosystem health, particularly under anoxic conditions. The Zhoushan Islands are located east of the Changjiang river estuary, and collect a high load of anthropogenic nitrogen, which leads to severe eutrophication and seasonal hypoxia. Therefore, bacteria that mediate the anammox process are of major interest in this area. Although the importance of anammox-mediating bacteria is known, few studies on these bacteria have been conducted in the East China Sea. To the best of our knowledge, this study is the first to report the diversity, community composition, and distribution of anammox bacteria in the Zhoushan Islands. Field surveys were conducted in June 2012; triplicate surface sediment samples were collected at each site and stored in sterile plastic bags at-80℃ for subsequent DNA extraction and molecular analysis. Total genomic DNA was extracted using the Fast DNA SPIN Kit for soil. Environmental DNA extracted from sediment samples was used as the template for PCR amplification of anammox 16S rRNA genes using primers Amx368f—Amx820r. The purified fragments were cloned and sequenced for phylogenetic and statistical analyses. In total, 297 sequences belonging to 16 operational taxonomic units ( OTUs) were obtained from five 16S rRNA gene libraries. The biodiversity of anammox bacteria was examined using rarefaction analysis of the 16S rRNA genes, the Chao1 estimator, and Shannon index calculations. EZ3-1, EZ3-3, and EZ1-5 exhibited higher diversity than EZ1-3 and EZ3-5. A significant positive correlation between Shannon index and organic carbon content indicate that sediment organic carbon content plays an important role in modulating anammox bacterial diversity in the Zhoushan Island area. Weighted UniFrac PCoA analysis of the 16S rRNA genes demonstrated spatial heterogeneity in the community composition of anammox bacteria; the anammox bacteria in

  3. Elemental sulfur formation and nitrogen removal from wastewaters by autotrophic denitrifiers and anammox bacteria.

    Science.gov (United States)

    Liu, Chunshuang; Zhao, Dongfeng; Yan, Laihong; Wang, Aijie; Gu, Yingying; Lee, Duu-Jong

    2015-09-01

    Elemental sulfur (S(0)) formation from and nitrogen removal on sulfide, nitrate and ammonium-laden wastewaters were achieved by denitrifying ammonium oxidation (DEAMOX) reactor with autotrophic denitrifiers and anaerobic ammonium oxidation (anammox) bacteria. The sulfide to nitrate ratio is a key process parameter for excess accumulation of S(0) and a ratio of 1.31:1 is a proposed optimum. The Alishewanella, Thauera and Candidatus Anammoximicrobium present respectively the autotrophic denitrifiers and anammox bacteria for the reactor. DEAMOX is demonstrated promising biological process for treating organics-deficient (S+N) wastewaters with excess S(0) production. PMID:26022701

  4. Identification of the type II cytochrome c maturation pathway in anammox bacteria by comparative genomics

    OpenAIRE

    Ferousi, Christina; Speth, Daan R.; Reimann, Joachim; Op den Camp, Huub JM; Allen, James WA; Keltjens, Jan TM; Jetten, Mike SM

    2013-01-01

    Background Anaerobic ammonium oxidizing (anammox) bacteria may contribute up to 50% to the global nitrogen production, and are, thus, key players of the global nitrogen cycle. The molecular mechanism of anammox was recently elucidated and is suggested to proceed through a branched respiratory chain. This chain involves an exceptionally high number of c-type cytochrome proteins which are localized within the anammoxosome, a unique subcellular organelle. During transport into the organelle the ...

  5. Combination of upflow anaerobic sludge blanket (UASB) reactor and partial nitritation/anammox moving bed biofilm reactor (MBBR) for municipal wastewater treatment.

    Science.gov (United States)

    Malovanyy, Andriy; Yang, Jingjing; Trela, Jozef; Plaza, Elzbieta

    2015-03-01

    In this study the combination of an upflow anaerobic sludge blanket (UASB) reactor and a deammonification moving bed biofilm reactor (MBBR) for mainstream wastewater treatment was tested. The competition between aerobic ammonium oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) was studied during a 5months period of transition from reject water to mainstream wastewater followed by a 16months period of mainstream wastewater treatment. The decrease of influent ammonium concentration led to a wash-out of suspended biomass which had a major contribution to nitrite production. Influence of a dissolved oxygen concentration and a transient anoxia mechanism of NOB suppression were studied. It was shown that anoxic phase duration has no effect on NOB metabolism recovery and oxygen diffusion rather than affinities of AOB and NOB to oxygen determine the rate of nitrogen conversion in a biofilm system. Anammox activity remained on the level comparable to reject water treatment systems. PMID:25600011

  6. Study on one-stage Partial Nitritation-Anammox process in Moving Bed Biofilm Reactors: a sustainable nitrogen removal.

    OpenAIRE

    Bertino, Andrea

    2011-01-01

    In the last decade, several novel and cost-effective biological nitrogen removal technologies have been developed. The discovery of anaerobic ammonium oxidation (Anammox), about 15 years ago, has resulted in new opportunities for research and development of sustainable nitrogen removal systems. Compared to conventional nitrification/denitrification, Anammox eliminates necessity of external organic carbon source, has a smaller production of excess sludge, reduces energy demand for aeration (up...

  7. Optimization and Modelling of Chemical Oxygen Demand Removal by ANAMMOX Process Using Response Surface Methodology

    OpenAIRE

    Ali Jalilzadeh; Ramin Nabizadeh; Alireza Mesdaghinia; Aliakbar Azimi; Simin Nasseri; Amir Hossein Mahvi; Kazem Naddafi

    2013-01-01

    A systematic model for chemical oxygen demand (COD) removal using the ANAMMOX (Anaerobic AMMonium OXidation) process was provided based on an experimental design. At first, the experimental data was collected from a combined biological aerobic/anaerobic reactor. For modelling and optimization of COD removal, the main parameters were considered, such as COD loading, ammonium, pH, and temperature. From the models, the optimum conditions were determined as COD 97.5 mg/L, ammonium concentration e...

  8. Influence of Chemical Oxygen Demand Concentrations on Anaerobi Ammonium Oxidation by Granular Sludge From EGSB Reactor

    Institute of Scientific and Technical Information of China (English)

    JING KANG; JIAN-LONG WANG

    2006-01-01

    Objective To investigate the effect of chemical oxygen demand (COD) concentrations on the anaerobic ammonium oxidation (ANAMMOX). Methods An Expanded Granular Sludge Bed (EGSB) reactor was used to cultivate the granular sludge and to perform the ANAMMOX reaction in the bench scale experiment. NH4+-N and NO2--N were measured by usingcolorimetric method. NO3--N was analyzed by using the UV spectrophotometric method. COD measurement was based on digestion with potassium dichromate in concentrated sulphuric acid. Results When the COD concentrations in the reactors were 0 mg/L, 200 mg/L, 350 mg/L, and 550 mg/L, respectively, the NH4+-N removal efficiency was 12.5%, 14.2%, 14.3%, and 23.7%; the removal amount of NO2--N was almost the same; the nitrate removal efficiency was 16.8%, 94.5%, 86.6%, and 84.2% and TN removal efficiency was 16.3%, 50.7%, 46.9%, and 50.4%, moreover, the COD removal efficiency concentrations have a significant influence on anaerobic ammonium oxidation by granular sludge.

  9. Metatranscriptomic Analysis of Groundwater Reveals an Active Anammox Bacterial Population

    Science.gov (United States)

    Jewell, T. N. M.; Karaoz, U.; Thomas, B. C.; Banfield, J. F.; Brodie, E.; Williams, K. H.; Beller, H. R.

    2014-12-01

    Groundwater is a major natural resource, yet little is known about the contribution of microbial anaerobic ammonium oxidation (anammox) activity to subsurface nitrogen cycling. During anammox, energy is generated as ammonium is oxidized under anaerobic conditions to dinitrogen gas, using nitrite as the final electron acceptor. This process is a global sink for fixed nitrogen. Only a narrow range of monophyletic bacteria within the Planctomycetes carries out anammox, and the full extent of their metabolism, and subsequent impact on nitrogen cycling and microbial community structure, is still unknown. Here, we employ a metatranscriptomic analysis on enriched mRNA to identify the abundance and activity of a population of anammox bacteria within an aquifer at Rifle, CO. Planktonic biomass was collected over a two-month period after injection of up to 1.5 mM nitrate. Illumina-generated sequences were mapped to a phylogenetically binned Rifle metagenome database. We identified transcripts for genes with high protein sequence identities (81-98%) to those of anammox strain KSU-1 and to two of the five anammox bacteria genera, Brocadia and Kuenenia, suggesting an active, if not diverse, anammox population. Many of the most abundant anammox transcripts mapped to a single scaffold, indicative of a single dominant anammox species. Transcripts of the genes necessary for the anammox pathway were present, including an ammonium transporter (amtB), nitrite/formate transporter, nitrite reductase (nirK), and hydrazine oxidoreductase (hzoB). The form of nitrite reductase encoded by anammox is species-dependent, and we only identified nirK, with no evidence of anammox nirS. In addition to the anammox pathway we saw evidence of the anammox bacterial dissimilatory nitrate reduction to ammonium pathway (narH, putative nrfA, and nrfB), which provides an alternate means of generating substrates for anammox from nitrate, rather than relying on an external pool. Transcripts for hydroxylamine

  10. Start-Up Characteristics of a Granule-Based Anammox UASB Reactor Seeded with Anaerobic Granular Sludge

    Directory of Open Access Journals (Sweden)

    Lei Xiong

    2013-01-01

    Full Text Available The granulation of anammox sludge plays an important role in the high nitrogen removal performance of the anammox reactor. In this study, anaerobic granular sludge was selected as the seeding sludge to start up anammox reactor in order to directly obtain anammox granules. Results showed that the anammox UASB reactor was successfully started up by inoculating anaerobic granular sludge, with substrate capacity of 4435.2 mg/(L·d and average ammonium and nitrite removal efficiency of 90.36% and 93.29%, respectively. During the start-up course, the granular sludge initially disintegrated and then reaggregated and turned red, suggesting the high anammox performance. Zn-Fe precipitation was observed on the surface of granules during the operation by SEM-EDS, which would impose inhibition to the anammox activity of the granules. Accordingly, it is suggested to relatively reduce the trace metals concentrations, of Fe and Zn in the conventional medium. The findings of this study are expected to be used for a shorter start-up and more stable operation of anammox system.

  11. The relationship between anammox and denitrification in the sediment of an inland river

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Sheng, E-mail: zhous@outlook.com [Eco-environmental Protection Research Institute, Shanghai Academy of Agricultural Sciences, No. 1000 Jinqi Road, Shanghai 201403 (China); Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan); Borjigin, Sodbilig; Riya, Shohei; Terada, Akihiko; Hosomi, Masaaki [Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588 (Japan)

    2014-08-15

    This study measured the microbial processes of anaerobic ammonium oxidation (anammox) and denitrification in sediment sampled from two sites in the estuary of an inland river (Koisegawa River, Ibaragi prefecture, Japan) using a nitrogen isotope pairing technique (IPT). The responses of anammox and denitrification activities to temperature and nitrate concentration were also evaluated. Further, to elucidate the correlation between anammox and denitrification processes, an inhibition experiment was conducted, using chlorate to inhibit the first step of denitrification. Denitrification activity was much higher than anammox activity, and it reached a maximum at the surface layer in February 2012. Denitrification activity decreased as sediment depth increased, and a similar phenomenon was observed for anammox activity in the sediment of site A, where aquatic plants were absent from the surroundings. The activities of both denitrification and anammox were temperature-dependent, but they responded differently to changes in incubation temperature. Compared to a linear increase in denitrification as temperature rose to 35 °C, the optimal temperature for anammox was 25 °C, after which the activity decreased sharply. At the same time, both anammox and denitrification activities increased with NO{sub 3}{sup −} concentration. The Michaelis–Menten kinetic constants (V{sub max} and K{sub m}) of denitrification were significantly higher than those of the anammox process. Furthermore, anammox activity decreased accordingly when the first step of denitrification was inhibited, which probably reduced the amount of the intermediate NO{sub 2}{sup −}. Our study provides the first direct exploration of the denitrification-dependent correlation of anammox activity in the sediment of inland river. - Highlights: • The activity of denitrification in river sediment was much higher than anammox. • Denitrification and anammox respond differently to changes in temperature.

  12. A robust and cost-effective integrated process for nitrogen and bio-refractory organics removal from landfill leachate via short-cut nitrification, anaerobic ammonium oxidation in tandem with electrochemical oxidation.

    Science.gov (United States)

    Wu, Li-Na; Liang, Da-Wei; Xu, Ying-Ying; Liu, Ting; Peng, Yong-Zhen; Zhang, Jie

    2016-07-01

    A cost-effective process, consisting of a denitrifying upflow anaerobic sludge blanket (UASB), an oxygen-limited anoxic/aerobic (A/O) process for short-cut nitrification, and an anaerobic reactor (ANR) for anaerobic ammonia oxidation (anammox), followed by an electrochemical oxidation process with a Ti-based SnO2-Sb2O5 anode, was developed to remove organics and nitrogen in a sewage diluted leachate. The final chemical oxygen demand (COD), ammonia nitrogen (NH4(+)-N) and total nitrogen (TN) of 70, 11.3 and 39 (all in mg/L), respectively, were obtained. TN removal in UASB, A/O and ANR were 24.6%, 49.6% and 16.1%, respectively. According to the water quality and molecular biology analysis, a high degree of anammox besides short-cut nitrification and denitrification occurred in A/O. Counting for 16.1% of TN removal in ANR, at least 43.2-49% of TN was removed via anammox. The anammox bacteria in A/O and ANR, were in respective titers of (2.5-5.9)×10(9) and 2.01×10(10)copy numbers/(gSS). PMID:27115616

  13. The effect of sulfide inhibition on the ANAMMOX process.

    Science.gov (United States)

    Jin, Ren-Cun; Yang, Guang-Feng; Zhang, Qian-Qian; Ma, Chun; Yu, Jin-Jin; Xing, Bao-Shan

    2013-03-01

    The feasibility of anaerobic ammonium oxidation (ANAMMOX) process to treat wastewaters containing sulfide was studied in this work. Serum bottles were used as experimental containers in batch tests to analyze the short-term response of the ANAMMOX process under sulfide stress. The IC(50) of sulfide-S for ANAMMOX biomass was substrates-dependent and was calculated to be 264 mg L(-1) at an initial total nitrogen level of 200 mg L(-1) (molar ratio of ammonium and nitrite was 1:1). The long-term effects and the performance recovery under sulfide stress were continuously monitored and evaluated in an upflow anaerobic sludge blanket reactor. The performance of the ANAMMOX system was halved at an sulfide-S level of 32 mg L(-1) within 13 days; however, the nitrogen removal rate (NRR) decreased by only 17.2% within 18 days at an sulfide-S concentration of 40 mg L(-1) after long-time acclimatization of sludge in the presence of sulfide. The ANAMMOX performance recovered under sulfide-S level of 8 mg L(-1) with a steady NRR increasing speed, linear relationship between the NRR and operation time. The synchronic reduce in the specific ANAMMOX activity and the biomass extended the apparent doubling time of the nitrogen removal capacity and decreased biomass growth rate. PMID:23273856

  14. Effects of organic matter in livestock manure digester liquid on microbial community structure and in situ activity of anammox granules.

    Science.gov (United States)

    Kindaichi, Tomonori; Awata, Takanori; Mugimoto, Yuichiro; Rathnayake, Rathnayake M L D; Kasahara, Shinsuke; Satoh, Hisashi

    2016-09-01

    Anaerobic ammonium oxidation (anammox) is a promising process for NH4(+)-rich wastewaters such as anaerobic digester liquids. In the present study, we investigated various properties of an up-flow column reactor containing anammox granules and fed with a real digester liquid at four different concentrations (Phases 1 to 4). The efficiencies of NH4(+) and NO2(-) removal decreased by up to 32% and 42%, respectively, in the digester-liquid-fed reactor (reactor-DL). When the performance of reactor-DL deteriorated, the community structure, spatial distribution, and in situ anammox activity in the two reactors were further investigated using 16S rRNA gene-based phylogenetic analysis, fluorescence in situ hybridization (FISH), and microelectrode measurements. The phylogenetic analysis and FISH results showed that non-anammox bacteria were predominant in the granule outer layers in reactor-DL, whereas anammox bacteria still dominated the granule interiors. Microelectrode measurements showed clear evidence of NH4(+) oxidation activity in the interiors of granules from reactor-DL. Batch experiments using anammox granules at different acetate concentrations indicated that concentrations up to 50 mM had no effects on the anammox activity, whereas inorganic carbon uptake decreased in the presence of acetate. The present study clearly shows that the anammox activity and anammox bacterial density in the granules were maintained after feeding the digester liquid to the reactor for 140 days. PMID:27314631

  15. Aeration Strategies To Mitigate Nitrous Oxide Emissions from Single-Stage Nitritation/Anammox Reactors

    DEFF Research Database (Denmark)

    Domingo Felez, Carlos; Mutlu, A. Gizem; Jensen, Marlene Mark;

    2014-01-01

    -stage nitritation/anammox were operated under different aeration strategies, gradually adjusted over six months. At constant but limiting oxygen loading, synthetic reject water was fed (0.75g-N/L.d) and high nitrogen removal efficiencies (83 +/- 5 and 88 +/- 2%) obtained. Dynamics of liquid phase nitrous (N2O) and...... conditions where anaerobic exceeds aerobic ammonium oxidation activity is proposed to minimize N2O emissions from single-stage nitritation/anammox reactors; increasing the frequency of aeration cycling is an efficient way of obtaining those conditions....

  16. Coupling between anammox and autotrophic denitrification for simultaneous removal of ammonium and sulfide by enriched marine sediments.

    Science.gov (United States)

    Rios-Del Toro, E Emilia; Cervantes, Francisco J

    2016-06-01

    In the present study, the capacity of enrichments derived from marine sediments collected from different sites of the Mexican littoral to perform anaerobic ammonium oxidation (anammox) coupled to sulfide-dependent denitrification for simultaneous removal of ammonium and sulfide linked to nitrite reduction was evaluated. Sulfide-dependent denitrification out-competed anammox during the simultaneous oxidation of sulfide and ammonium. Significant accumulation of elemental sulfur (ca. 14-30 % of added sulfide) occurred during the coupling between the two respiratory processes, while ammonium was partly oxidized (31-47 %) due to nitrite limitation imposed in sediment incubations. Nevertheless, mass balances revealed up to 38 % more oxidation of the electron donors available (ammonium and sulfide) than that expected from stoichiometry. Recycling of nitrite, from nitrate produced through anammox, is proposed to contribute to extra oxidation of sulfide, while additional ammonium oxidation is suggested by sulfate-reducing anammox (SR-anammox). The complex interaction between nitrogenous and sulfurous compounds occurring through the concomitant presence of autotrophic denitrification, conventional anammox and SR-anammox may significantly drive the nitrogen and sulfur fluxes in marine environments. PMID:26994921

  17. Enrichment of anammox from activated sludge and its application in the CANON process.

    Science.gov (United States)

    Third, K A; Paxman, J; Schmid, M; Strous, M; Jetten, M S M; Cord-Ruwisch, R

    2005-02-01

    A microbial culture capable of actively oxidizing ammonium to dinitrogen gas in the absence of oxygen, using nitrite as the electron acceptor, was enriched from local activated sludge (Western Australia) in activity achieved by the anaerobic culture was 0.26 mmol NH (4) (+) (g biomass)(-1) h(-1) (0.58 kg total-N m(-3) day(-1)). Qualitative FISH analysis (fluorescence in situ hybridization) confirmed the phylogenetic position of the enriched microorganism as belonging to the order Planctomycetales, in which all currently identified anammox strains fall. Preliminary FISH analysis suggests the anammox strain belongs to the same phylogenetic group as the Candidatus 'Brocadia anammoxidans' strain discovered in the Netherlands. However, there are quite a few differences in the target sites for the more specific probes of these organisms and it is therefore likely to represent a new species of anammox bacteria. A small amount of aerobic ammonium-oxidizing biomass was inoculated into the anammox reactor (10% v/v) to initiate completely autotrophic nitrogen removal over nitrite (the CANON process) in chemostat culture. The culture was always under oxygen limitation and no organic carbon was added. The CANON reactor was operated as an intermittently aerated system with 20 min aerobiosis and 30 min anaerobiosis, during which aerobic and anaerobic ammonium oxidation were performed in sequential fashion, respectively. Anammox was not inhibited by repeated intermittent exposure to oxygen, allowing sustained, completely autotrophic ammonium removal (0.08 kg N m(-3) day(-1)) for an extended period of time. PMID:15735941

  18. Mixing Intensity Effects of Attached Growth on Enriched Anammox Cultures

    Directory of Open Access Journals (Sweden)

    Pongsak Noophan

    2015-01-01

    Full Text Available Anaerobic ammonium oxidation (anammox is a promising new technology for the treatment of wastewater with high ammonium and low carbon concentrations. Earlier work suggests that optimal processing would be realized within a sequencing batch reactor (SBR. However, the relatively slow growth of anammox bacteria inhibits the rates of nitrogen removal and biomass yielding. Improved anammox performance has been demonstrated when the bacteria are in granular form or attached to a growth medium. Little has been reported concerning the effect of mixing rate on nitrogen (N removal with attached anammox bacteria. This work subjected anammox bacteria attached to polystyrene sponge in SBR to various intensities of impeller mixing and studied the effect on NH4+ and NO2- removal. Nitrogen processing was virtually the same with velocity gradient values between 13.5 and 222 s-1. More vigorous mixing at 407 and 666 s-1 values significantly inhibited N removal, likely due to detachment of bacteria from the growth medium. Following the poor N removal at the two higher mixing intensities, agitation was reduced to 24.8 s-1 velocity gradient value. Recovery of N removal rates required 2-3 weeks, the slow time attributed to slow reattachment to the growth medium. Denaturing gradient gel electrophoresis (DGGE analysis identified the prominent anammox species in the experimental study as Candidatus Brocadia anammoxidans and Candidatus Kuenenia stuttgartiensis.

  19. Assessment of Heterotrophic Growth Supported by Soluble Microbial Products in Anammox Biofilm using Multidimensional Modeling

    Science.gov (United States)

    Liu, Yiwen; Sun, Jing; Peng, Lai; Wang, Dongbo; Dai, Xiaohu; Ni, Bing-Jie

    2016-01-01

    Anaerobic ammonium oxidation (anammox) is known to autotrophically convert ammonium to dinitrogen gas with nitrite as the electron acceptor, but little is known about their released microbial products and how these are relative to heterotrophic growth in anammox system. In this work, we applied a mathematical model to assess the heterotrophic growth supported by three key microbial products produced by bacteria in anammox biofilm (utilization associated products (UAP), biomass associated products (BAP), and decay released substrate). Both One-dimensional and two-dimensional numerical biofilm models were developed to describe the development of anammox biofilm as a function of the multiple bacteria–substrate interactions. Model simulations show that UAP of anammox is the main organic carbon source for heterotrophs. Heterotrophs are mainly dominant at the surface of the anammox biofilm with small fraction inside the biofilm. 1-D model is sufficient to describe the main substrate concentrations/fluxes within the anammox biofilm, while the 2-D model can give a more detailed biomass distribution. The heterotrophic growth on UAP is mainly present at the outside of anammox biofilm, their growth on BAP (HetB) are present throughout the biofilm, while the growth on decay released substrate (HetD) is mainly located in the inner layers of the biofilm. PMID:27273460

  20. Anammox enrichment from different conventional sludges.

    Science.gov (United States)

    Chamchoi, Nutchanat; Nitisoravut, Suwanchai

    2007-02-01

    Three sets of sequencing batch reactor (SBR) were used for Anammox enrichment from conventional sludges including upflow anaerobic sludge blanket, activated sludge, and anaerobic digestion sludge. After four months of operation, the Anammox activity occurred in all reactors allowing continuous removal of ammonium and nitrite. The morphology of the cultivated Anammox sludge was observed using scanning electron microscope. The photographs showed that the obtained culture was mostly spherical in shape, presumably Anammox culture. There were also filamentous-like bacteria co-existing in the system. Fluorescence in situ hybridization (FISH) analysis using 16S rRNA targeting oligonucleotide probes PLA46 and Amx820 showed that the dominant population developed in all SBRs was hybridized with both PLA46 and Amx820 gene probes. It means that the cultivated biomass in all SBRs was classified in the group of Planctomycetales bacteria with respect to the anaerobic ammonium-oxidizing bacteria, Candidatus Brocadia anammoxidans and Candidatus Kuenenia stuttgartiensis. Numerous time sequences were tested in this experiment. The shortest workable reaction time was found in the range from 5 to 7 h. Good quiescence of sludge was obtained at 30 min of settle period followed by a discharge period of 15 min. A long-term performance showed a near perfect removal of nitrite based on the influent NO2(-)-N concentration of 50-70 mg l(-1). The maximum ammonia removal efficiency was 80% with the influent NH4(+)-N concentration of 40-60 mg l(-1). It is, therefore, concluded that Anammox cultivation from conventional sludges was highly possible under control environment within four months. PMID:17207839

  1. Operational strategy for nitrogen removal from centrate in a two-stage partial nitrification--anammox process.

    Science.gov (United States)

    Kosari, S F; Rezania, B; Lo, K V; Mavinic, D S

    2014-01-01

    This paper presents the operational strategy for nitrogen removal in a two-stage, partial nitrification (PN) process coupled with anaerobic ammonium oxidation (Anammox) process. The process was used to remove ammonium from centrate obtained from a full-scale, wastewater treatment plant in British Columbia, Canada. The PN, which was carried out in a sequencing batch reactor (SBR), successfully converted approximately 49.5 +/- 1.0% of ammonium to nitrite. The operation of SBR under higher dissolved oxygen in combination with slow feeding resulted in significant reduced HRT without nitrate accumulation. Partially nitrified centrate was further treated in Anammox reactors, where the mixture of ammonium and nitrite was converted mainly to nitrogen gas. Anammox treatment was carried out in two different types of Anammox reactors: a moving bed hybrid reactor and an up-flow fixed-bed biofilm reactor. The hybrid Anammox reactor removed an average of 55.8% of NH4-N, versus the 48.3% NH4-N removed in the up-flow fixed-bed reactor. Nitrite removal in the hybrid and up-flow fixed-bed Anammox reactors averaged 80.8% and 62.5%, respectively. This study also illustrated that in both Anammox reactors, better ammonium removal was achieved when the nitrite to ammonium ratio is between 1.35 and 1.45. As such, alkalinity was found to neither control nor limit the Anammox reaction. PMID:24701906

  2. Feasibility of enhancing the DEnitrifying AMmonium OXidation (DEAMOX) process for nitrogen removal by seeding partial denitrification sludge.

    Science.gov (United States)

    Cao, Shenbin; Peng, Yongzhen; Du, Rui; Wang, Shuying

    2016-04-01

    The recently proposed DEnitrifying AMmonium OXidation (DEAMOX) process combined anaerobic ammonia oxidation (ANAMMOX) with denitrification to convert nitrate to nitrite, which was a promising way for treating wastewater containing nitrate and ammonia. This study investigated the feasibility of establishing DEAMOX process by seeding partial denitrification sludge (NO3(-) → NO2(-)) using sodium acetate as an electron donor in a sequencing batch reactor. Results showed that the DEAMOX process was established successfully and operated stably in 114-days operation. The average effluent total nitrogen concentration was below 5 mg L(-1) and TN removal efficiency reached up to 97% at COD/NO3(-) ratio of 3.0 under initial NH4(+) concentration of 25 mg L(-1) and NO3(-) of 30 mg L(-1). It suggested that the presence of NO2(-) in the system supplied for ANAMMOX and the relatively long sludge retention time (SRT) for denitrifiers were attributed to commendable coexistence of ANAMMOX and denitrifying bacteria. PMID:26829308

  3. Importance of Anammox to the Nitrogen Removal in Deep Cascadian Basin Sediments

    Science.gov (United States)

    Engstrom, P.; Penton, C. R.; Devol, A. H.

    2006-12-01

    Anammox is a recently discovered N2 producing pathway where NH4+ is oxidized by NO2- to form N2. Before anammox was discovered in a waste water treatment plant in the mid 1990-ties, denitrification was considered the only removal mechanism for bio-available N in the ocean. In marine sediments, the importance of anammox is suggested to increase with water depth. At the deepest site reported (700 m), anammox account for 67-79 percent of total N2 production. If these estimates are consistent for sediments at depths >700 m, anammox would be responsible for at least 2/3 of the total N2 production in deep sediments which suggest this pathway to be highly significant in global N cycling. We investigated the role of anammox in deep sea sediments of the Cascadian basin using microbiological and biogeochemical techniques. Anammox and denitrification rates were measured at depths 2700-3200 m at eight sites in August 2006. Sediments were collected with a Multicorer and 15N isotope pairing was used together with analyses of solute pore water distribution of inorganic N and O2 to estimate activity rates and distribution of anammox and denitrification in the sediment. Pore water profiles of NO2-, NO3-, NH4+ and O2 at all sites show a removal of ammonium in the suboxic zone that strongly suggest an anaerobic ammonium oxidation by nitrite or nitrate. Minimum ammonium removal rates were estimated to vary between 1.7-31 umol NH4+ m-2 day-1 among the 8 stations. The thickness of the ammonium removal zone suggesting anammox activity increased at sites further off the coast (from 1-11 cm) and correlated to the NO2-+NO3- distribution in the sediment. Preliminary results strongly suggest an extensive anammox activity in these sediments responsible for at least 20-60 percent of total benthic N2 production in the Cascadian basin.

  4. High-rate nitrogen removal by the Anammox process with a sufficient inorganic carbon source.

    Science.gov (United States)

    Yang, Jiachun; Zhang, Li; Fukuzaki, Yasuhiro; Hira, Daisuke; Furukawa, Kenji

    2010-12-01

    This study focused on high-rate nitrogen removal by the anaerobic ammonium oxidation (Anammox) process with a sufficient inorganic carbon (IC) source. Experiments were carried out in an up-flow column Anammox reactor fed with synthetic inorganic wastewater for 110 days. The IC source was added into the influent tank in the form of bicarbonate. The results confirmed the positive impact of inorganic matter on stimulating Anammox activity. After the addition of sufficient IC, the nitrogen removal rate sharply increased from 5.2 to 11.8 kg-Nm(-3)day(-1) within only 32 days. NO(2)-N inhibition was not observed even at NO(2)-N concentrations greater than 460 mgN/L, indicating the enriched Anammox consortium adapted to high NO(2)-N concentrations. The ratio of NO(2)-N removal, NO(3)-N production and NH(4)-N removal for the reactor was correspondingly changed from 1.21:0.21:1 to 1.24:0.18:1. Simultaneously, the sludge volume index of the Anammox granules decreased markedly from 36.8 to 21.5 mL/g, which was attributed to the implementation of proper operational strategy. In addition, DNA analysis revealed that a shift from the KSU-1 strain to the KU2 strain occurred in the Anammox community. PMID:20709538

  5. Three-Dimensional Stratification of Bacterial Biofilm Populations in a Moving Bed Biofilm Reactor for Nitritation-Anammox

    Directory of Open Access Journals (Sweden)

    Robert Almstrand

    2014-01-01

    Full Text Available Moving bed biofilm reactors (MBBRs are increasingly used for nitrogen removal with nitritation-anaerobic ammonium oxidation (anammox processes in wastewater treatment. Carriers provide protected surfaces where ammonia oxidizing bacteria (AOB and anammox bacteria form complex biofilms. However, the knowledge about the organization of microbial communities in MBBR biofilms is sparse. We used new cryosectioning and imaging methods for fluorescence in situ hybridization (FISH to study the structure of biofilms retrieved from carriers in a nitritation-anammox MBBR. The dimensions of the carrier compartments and the biofilm cryosections after FISH showed good correlation, indicating little disturbance of biofilm samples by the treatment. FISH showed that Nitrosomonas europaea/eutropha-related cells dominated the AOB and Candidatus Brocadia fulgida-related cells dominated the anammox guild. New carriers were initially colonized by AOB, followed by anammox bacteria proliferating in the deeper biofilm layers, probably in anaerobic microhabitats created by AOB activity. Mature biofilms showed a pronounced three-dimensional stratification where AOB dominated closer to the biofilm-water interface, whereas anammox were dominant deeper into the carrier space and towards the walls. Our results suggest that current mathematical models may be oversimplifying these three-dimensional systems and unless the multidimensionality of these systems is considered, models may result in suboptimal design of MBBR carriers.

  6. Environmental Factors Affecting Ammonium Oxidation Under Iron Reducing Conditions

    Science.gov (United States)

    Jaffe, P. R.; Huang, S.; Ruiz-Urigüen, M.

    2014-12-01

    35ºC. This is in contrast to anammox, another anaerobic ammonium oxidation pathway, for which optimal NH4+ oxidation is at temperatures ~ 30ºC. Hence, a Feammox-based process is an attractive candidate for wastewater treatment that could result in further energy savings, by requiring no aeration or heating of the wastewater in temperate climates.

  7. Microbial Aggregate and Functional Community Distribution in a Sequencing Batch Reactor with Anammox Granules

    KAUST Repository

    Sun, Shan

    2013-05-01

    Anammox (anaerobic ammonium oxidation) process is a one-step conversion of ammonia into nitrogen gas with nitrite as an electron acceptor. It has been developed as a sustainable technology for ammonia removal from wastewater in the last decade. For wastewater treatment, anammox biomass was widely developed as microbial aggregate where the conditions for enrichment of anammox community must be delicately controlled and growth of other bacteria especially NOB should be suppressed to enhance nitrogen removal efficiency. Little is known about the distribution of microbial aggregates in anammox process. Thus the objective of our study was to assess whether segregation of biomass occurs in granular anammox system. In this study, a laboratory-scale sequential batch reactor (SBR) was successfully operated for a period of 80 days with granular anammox biomass. Temporal and spatial distribution of microbial aggregates was studied by particle characterization system and the distribution of functional microbial communities was studied with qPCR and 16s rRNA amplicon pyrosequencing. Our study revealed the spatial and temporal distribution of biomass aggregates based on their sizes and density. Granules (>200 μm) preferentially accumulated in the bottom of the reactor while floccules (30-200 μm) were relatively rich at the top layer. The average density of aggregate was higher at the bottom than the density of those at the top layer. Degranulation caused by lack of hydrodynamic shear force in the top layer was considered responsible for this phenomenon. NOB was relatively rich in the top layer while percentage of anammox population was higher at the bottom, and anammox bacteria population gradually increased over a period of time. NOB growth was supposed to be associated with the increase of floccules based on the concurrent occurrence. Thus, segregation of biomass can be utilized to develop an effective strategy to enrich anammox and wash out NOB by shortening the settling

  8. [Physicochemical and ecological characteristics of the granular sludge during start-up of Anammox reactor].

    Science.gov (United States)

    Song, Yuxia; Xiong, Lei; Chai, Liyuan; Liao, Qi; Tang, Chongjian; Min, Xiaobo; Yang, Zhihui

    2014-12-01

    The anaerobic granular sludge from an Internal Circulation (IC) reactor of a paper mill wastewater treatment plant were seeded in an Anammox upflow anaerobic sludge blanket reactor. After 185 days operation, the reactor was finally started up by increasing the influent ammonium and nitrite concentrations to 224 mg/L and 255 mg/L, respectively, with volumetric nitrogen removal rate increasing to 3.76 kg/(m3·d). The physicochemical characteristics of the cultivated Anammox granules were observed by scanning electron microscope, transmission electron microscope and Fourier Transform infrared spectroscopy (FTIR). Results suggested that during the start-up course, the granular sludge initially disintegrated and then re-aggregated. FTIR spectra results revealed that the Anammox granular sludge contained abundant functional groups, indicating that it may also possess good adsorption properties. The ecological structure of the granular sludge, analyzed by the metagenomic sequencing methods, suggested that the relative abundance of the dominant bacterial community in the seeding sludge, i.e., Proteobacteria, Firmicutes, Bacteroidetes, significantly reduced, while Planctomycetes which contains anaerobic ammonium oxidation bacteria remarkably increased from 1.59% to 23.24% in the Anammox granules. PMID:26016375

  9. Comparison of sidestream treatment technologies: post aerobic digestion and Anammox.

    Science.gov (United States)

    Bauer, Heidi; Johnson, Thomas D; Johnson, Bruce R; Oerke, David; Graziano, Steven

    2016-01-01

    Post aerobic digestion (PAD) and anaerobic ammonium oxidation (Anammox) are sidestream treatment technologies which are both excellent options for the reduction of nitrogen recycled back to the liquid stream without the need for supplemental carbon or alkalinity. However, the achievement of this goal is where the similarities between the two technologies end. PAD is an advanced digestion process where aerobic digestion is designed to follow anaerobic digestion. Other benefits of PAD include volatile solids reduction, odor reduction, and struvite formation reduction. Anammox harnesses a specific species of autotrophic bacteria that can help achieve partial nitritation/deammonification. Other benefits of Anammox include lower energy consumption due to requiring less oxygen compared with conventional nitrification. This manuscript describes the unique benefits and challenges of each technology. Example installations are presented with a narrative of how and why the technology was selected. A whole plant simulator is used to compare and contrast the mass balances and net present value costs on an 'apples to apples' basis. The discussion includes descriptions of conditions under which each technology would potentially be the most beneficial and cost-effective against a baseline facility without sidestream treatment. PMID:27232417

  10. New anaerobic process of nitrogen removal.

    Science.gov (United States)

    Kalyuzhnyi, S; Gladchenko, M; Mulder, A; Versprille, B

    2006-01-01

    This paper reports on successful laboratory testing of a new nitrogen removal process called DEAMOX (DEnitrifying AMmonium OXidation) for the treatment of strong nitrogenous wastewater such as baker's yeast effluent. The concept of this process combines the recently discovered ANAMMOX (ANaerobic AMMonium OXidation) reaction with autotrophic denitrifying conditions using sulfide as an electron donor for the production of nitrite within an anaerobic biofilm. The achieved results with a nitrogen loading rate of higher than 1,000 mg/L/d and nitrogen removal of around 90% look very promising because they exceed (by 9-18 times) the corresponding nitrogen removal rates of conventional activated sludge systems. The paper describes also some characteristics of DEAMOX sludge, as well as the preliminary results of its microbiological characterization. PMID:17163025

  11. Effect of feed starvation on side-stream anammox activity and key microbial populations.

    Science.gov (United States)

    Reeve, Petra J; Mouilleron, Irina; Chuang, Hui-Ping; Thwaites, Ben; Hyde, Kylie; Dinesh, Nirmala; Krampe, Joerg; Lin, Tsair-Fuh; van den Akker, Ben

    2016-04-15

    The anaerobic ammonium oxidation (anammox) process is widely acknowledged to be susceptible to a wide range of environmental factors given the slow growth rate of the anammox bacteria. Surprisingly there is limited experimental data regarding the susceptibility of the anammox process to feed starvations which may be encountered in full-scale applications. Therefore, a study was established to investigate the impact of feed starvations on nitritation and anammox activity in a demonstration-scale sequencing batch reactor. Three starvation periods were trialled, lasting one fortnight (15 d), one month (33 d) and two months (62 d). Regardless of the duration of the starvation period, assessment of the ammonia removal performance demonstrated nitritation and anammox activity were reinstated within one day of recovery operation. Characterisation of the community structure using 16S rRNA and functional genes specific for nitrogen-related microbes showed there was no clear impact or shift in the microbial populations between starvation and recovery phases. PMID:26861222

  12. [Nitrogen removal performance of ANAMMOX ABR process in tannery wastewater treatment].

    Science.gov (United States)

    Zeng, Guo-Qu; Jia, Xiao-Shan

    2014-12-01

    Anaerobic ammonium-N removal from tannery wastewater was investigated using a lab-scale anaerobic baffled reactor (ABR). The results indicated that ABR could be used as a good anaerobic ammonium oxidation reactor, the stable and effective performance of ammonium-N and COD removal from tannery wastewater was demonstrated in the ANAMMOX ABR. When the NH4(+) -N concentration of the influents were in the range of 25.0 mg x L(-1) to 76.2 mg x L(-1) and COD ranged from 131 mg x L(-1) to 237 mg x L(-1), under the volumetric loading of 0.05 kg x (m3 x d)(-1) to 0.15 kg x (m3 x d)(-1), the NH4(+)-N and COD of the effluents were from 0.20 mg x L(-1) to 7.12 mg x L(-1) and from 35.1 mg x L(-1) to 69.2 mg x L(-1), respectively, and the removal efficiency of NH4(+) -N and COD were 90.8% to 99.6% and 66.9% to 74.7%, respectively. In addition, the brown-red, brown-yellow, red granular sludges were developed in ABR. SEM observation confirmed the presence of ANAMMOX bacteria in granular sludge of all four compartments of ANAMMOX ABR. According to FISH results, ANAMMOX bacteria had grown in all four compartments to various degrees during the acclimatization and running process, the percentage of ANAMMOX bacteria in sludge increased from 4% to 9%, 8%, 12% and 30% in compartment 1, compartment 2, compartment 3 and compartment 4, respectively, and a higher population percentage of ANAMMOX bacteria existed in the rear than in the front compartments. PMID:25826933

  13. [Community Characteristics of ANAMMOX Bacteria in Subsurface Flow Constructed Wetland (SSFCW) for Processing of Aquaculture Waster Water].

    Science.gov (United States)

    Zeng, Xian-lei; Liu, Xing-guo; Wu, Zong-fan; Shi, Xu; Lu, Shi-min

    2016-02-15

    Anaerobic ammonium oxidation (ANAMMOX) is one of the important functions in waste water treatment by subsurface flow constructed wetland (SSFCW), however, there are few studies on ANAMMOX in SSFCW environment at present. The community characteristics of ANAMMOX in the SSFCW of processing aquaculture waste water were explored in this study. In order to analyze the structure, diversity and abundance of ANAMMOX bacteria, several 16S rRNA clone libraries were constructed and real-time PCR targeting specific 16S rRNA genes together with diversity analysis was adopted. The obtained results showed that the SSFCW identified a total of three unknown clusters and two known clusters including Candidatus brocadia and Candidatus kuenenia. The dominant cluster was Candidatus brocadia. The highest diversity levels of ANAMMOX bacteria occurred in autumn (H', 1.21), while the lowest in spring (H', 0.64). The abundance of ANAMMOX bacteria in SSFCW environment ranged from 8.0 x 10(4) to 9.4 x 10(6) copies x g(-1) of fresh weight and the copy number of total bacterial 16S rRNA genes ranged from 7.3 x 10(9) to 9.1 x 10(10) copies x g(-1) of fresh weight during culture cycle. There were significant differences in the ANAMMOX bacteria abundances of different stratum and seasons in SSFCW environment, but the differences in total bacterial abundances were not obvious. In addition, the differences in ANAMMOX bacteria abundances in different stratum and seasons in SSFCW environment were irregular in different culture cycle. According to the distribution characteristics of ANAMMOX bacteria in the wetland, the denitrification effect of SSFCW could be improved by changing the supplying manners of aquaculture wastewater and adjusting the structure of wetland. The research results will provide reference for further optimizing the SSFCW and improving the efficiency of purification. PMID:27363152

  14. Molecular detection of Candidatus Scalindua pacifica and environmental responses of sediment anammox bacterial community in the Bohai Sea, China.

    Directory of Open Access Journals (Sweden)

    Hongyue Dang

    Full Text Available The Bohai Sea is a large semi-enclosed shallow water basin, which receives extensive river discharges of various terrestrial and anthropogenic materials such as sediments, nutrients and contaminants. How these terrigenous inputs may influence the diversity, community structure, biogeographical distribution, abundance and ecophysiology of the sediment anaerobic ammonium oxidation (anammox bacteria was unknown. To answer this question, an investigation employing both 16S rRNA and hzo gene biomarkers was carried out. Ca. Scalindua bacteria were predominant in the surface sediments of the Bohai Sea, while non-Scalindua anammox bacteria were also detected in the Yellow River estuary and inner part of Liaodong Bay that received strong riverine and anthropogenic impacts. A novel 16S rRNA gene sequence clade was identified, putatively representing an anammox bacterial new candidate species tentatively named "Ca. Scalindua pacifica". Several groups of environmental factors, usually with distinct physicochemical or biogeochemical natures, including general marine and estuarine physicochemical properties, availability of anammox substrates (inorganic N compounds, alternative reductants and oxidants, environmental variations caused by river discharges and associated contaminants such as heavy metals, were identified to likely play important roles in influencing the ecology and biogeochemical functioning of the sediment anammox bacteria. In addition to inorganic N compounds that might play a key role in shaping the anammox microbiota, organic carbon, organic nitrogen, sulfate, sulfide and metals all showed the potentials to participate in the anammox process, releasing the strict dependence of the anammox bacteria upon the direct availability of inorganic N nutrients that might be limiting in certain areas of the Bohai Sea. The importance of inorganic N nutrients and certain other environmental factors to the sediment anammox microbiota suggests that these

  15. Bacterial biodiversity from an anaerobic up flow bioreactor with ANAMMOX activity inoculated with swine sludge

    Science.gov (United States)

    The present study aimed to identify organisms with ANAMMOX activity in a reactor maintained in a laboratory. Molecular methods as fluorescence in situ hybridization (FISH), polymerase chain reaction (PCR) and cloning of 16S-rDNA genes probing for Planctomycetes were performed. Seventeen clones were ...

  16. Correlation between microbial community and granule conductivity in anaerobic bioreactors for brewery wastewater treatment

    DEFF Research Database (Denmark)

    Shrestha, Pravin; Malvankar, Nikhil S.; Werner, Jeffrey;

    2014-01-01

    Prior investigation of an upflow anaerobic sludge blanket (UASB) reactor treating brewery wastes suggested that direct interspecies electron transfer (DIET) significantly contributed to interspecies electron transfer to methanogens. To investigate DIET in granules further, the electrical...... previous studies, which have demonstrated that Geobacter species can donate electrons to methanogens that are typically predominant in anaerobic digesters, suggest that DIET may be a widespread phenomenon in UASB reactors treating brewery wastes....... conductivity and bacterial community composition of granules in fourteen samples from four different UASB reactors treating brewery wastes were investigated. All of the UASB granules were electrically conductive whereas control granules from ANAMMOX (ANaerobic AMMonium OXidation) reactors and microbial...

  17. Anaerobic ammonia oxidation in a fertilized paddy soil

    DEFF Research Database (Denmark)

    Zhu, Guibing; Wang, Shanyun; Wang, Yu;

    2011-01-01

    anammox 16S rRNA genes retrieved from the deeper soil were affiliated to ‘Brocadia’. The retrieval of mainly bacterial amoA sequences in the upper part of the paddy soil indicated that nitrifying bacteria may be the major source of nitrite for anammox bacteria in the cultivated horizon. In the deeper...... oxygen-limited parts, only archaeal amoA sequences were found, indicating that archaea may produce nitrite in this part of the soil. It is estimated that a total loss of 76 g N m−2 per year is linked to anammox in the paddy field.......Evidence for anaerobic ammonium oxidation in a paddy field was obtained in Southern China using an isotope-pairing technique, quantitative PCR assays and 16S rRNA gene clone libraries, along with nutrient profiles of soil cores. A paddy field with a high load of slurry manure as fertilizer was...

  18. Concurrent Activity of Anammox and Denitrifying Bacteria in the Black Sea

    Directory of Open Access Journals (Sweden)

    JohnB.Kirkpatrick

    2012-07-01

    Full Text Available After the discovery of ANaerobic AMMonium OXidation (anammox in the Black Sea in 2003, the role of heterotrophic denitrification as the main marine pathway for fixed N loss was questioned. A 3 part, 15 month time series investigating Black Sea nitrite reductase (nirS mRNA transcripts at a single location was conducted in order to better understand the activity of anammox and denitrifying bacteria. Here we show that both of these groups were active, as well as being concurrent in the lower suboxic zone over this time span. Their distributions, however, were fundamentally different; denitrification expression was much more variable. Depth profiles covering the suboxic zone showed that the four groups of anammox-type sequences were expressed consistently in the lower suboxic zone, and were consistent with anammox 16S rDNA gene profiles. By contrast, denitrifier-type nirS sequence groups were mixed; half of the groups exhibited consistent expression in the lower suboxic zone, while others varied between season and depth. Co-occurrence of both anammox and denitrifier expression was common and ongoing. Both types of transcripts were also found in samples with low concentrations of sulfide ( >2 μM. 6 major groups of denitrifier-type nirS transcripts were identified, making these transcripts more diverse than previous DNA clone libraries. Several groups of denitrifier-type nirS transcripts were closely related to sequences from the Baltic Sea. An increase in denitrifier-type nirS transcript diversity and depth range in October 2007 corresponded to an increase in mixed layer net community productivity as measured by O2/Ar gas ratios, as well as to an increase in N2 concentrations in the upper suboxic zone. Taken together, the variations in expression patterns between anammox and denitrification provide one explanation as to how near instantaneous rate measurements, such as isotope spike experiments, may regularly detect anammox activity but underreport

  19. Enrichment of anammox bacteria from three sludge sources for the startup of monosodium glutamate industrial wastewater treatment system.

    Science.gov (United States)

    Li-dong, Shen; An-hui, Hu; Ren-cun, Jin; Dong-qing, Cheng; Ping, Zheng; Xiang-yang, Xu; Bao-lan, Hu

    2012-01-15

    Three activated sludges from a landfill leachate treatment plant (S1), a municipal sewage treatment plant (S2) and a monosodium glutamate (MSG) wastewater treatment plant (S3) were used as inocula to enrich anaerobic ammonium oxidation (anammox) bacteria for the startup of MSG industrial wastewater treatment system. After 360 days of cultivation using MSG wastewater, obvious anammox activity was observed in all three cultures. The maximum specific anammox activities of cultures S1, S2 and S3 were 0.11 kg N kg(-1) VSS day(-1), 0.09 kg N kg(-1) VSS day(-1) and 0.16 kg N kg(-1) VSS day(-1), respectively. Brownish-red anammox granules having diameters in the range of 0.2-1.0mm were visible in cultures S1 and S2, and large red granules having diameters in the range of 0.5-2.5mm were formed in culture S3 after 420 days of cultivation. Phylogenetic analysis of 16S rRNA genes showed that Kuenenia organisms were the dominant anammox species in all three cultures. The copy numbers of 16S rRNA genes of anammox bacteria in cultures S1, S2 and S3 were 6.8 × 10(7) copies mL(-1), 9.4 × 10(7) copies mL(-1) and 7.5 × 10(8) copies mL(-1), respectively. The results of this study demonstrated that anammox cultivation from conventional activated sludges was highly possible using MSG wastewater. Thus the anammox process has possibility of applying to the nitrogen removal from MSG wastewater. PMID:22104770

  20. Two-step partial nitritation/Anammox process in granulation reactors: Start-up operation and microbial characterization.

    Science.gov (United States)

    Dosta, J; Vila, J; Sancho, I; Basset, N; Grifoll, M; Mata-Álvarez, J

    2015-12-01

    A two-stage Partial Nitritation (PN)/Anammox process was carried out at lab-scale conditions to treat reject water from a municipal WWTP. PN was achieved in a granular SBR obtaining an effluent with a NH4(+)-N/NO2(-)-N molar ratio around 1.0. The microbial characterization of this reactor revealed a predominance of Betaproteobacteria, with a member of Nitrosomonas as the main autotrophic ammonium oxidizing bacterium (AOB). Nitrite oxidizing bacteria (NOB) were under the detection limit of 16S rRNA gene pyrosequencing, indicating their effective inhibition. The effluent of the PN reactor was fed to an Anammox SBR where stable operation was achieved with a NH4(+)-N:NO2(-)-N:NO3(-)-N stoichiometry of 1:1.25:0.14. The deviation to the theoretical stoichiometry could be attributed to the presence of heterotrophic biomass in the Anammox reactor (mainly members of Chlorobi and Chloroflexi). Planctomycetes accounted for 7% of the global community, being members of Brocadia (1.4% of the total abundance) the main anaerobic ammonium oxidizer detected. PMID:26386756

  1. Successful start-up of the anammox process: Influence of the seeding strategy on performance and granule properties.

    Science.gov (United States)

    Chen, Hui; Hu, Hai-Yan; Chen, Qian-Qian; Shi, Man-Ling; Jin, Ren-Cun

    2016-07-01

    Successful start-up of the anaerobic ammonium oxidation (anammox) process in up-flow sludge blanket reactor was achieved by seeding denitrifying (R0) or mixed denitrifying-anammox granular sludge at a 3:1 volume ratio (R1). The results demonstrated that R1 was successfully started-up on day 40 and had a nitrogen removal rate (NRR) of 0.55kgNm(-3)d(-1). By contrast, it took 98days to start up R0 (0.54kgNm(-3)d(-1)). R0 and R1 achieved maximum NRRs of 5.70 and 12.02kgNm(-3)d(-1), respectively. The biogranules from R1 generally possessed greater specific anammox activity (SAA), higher extracellular polymeric substance (EPS) and heme c content, larger granules and greater settling velocity. Quantitative PCR (qPCR) and high-throughput sequencing techniques were used to monitor the evolution of the bacterial community. These results demonstrated the feasibility of seeding mixed denitrifying-anammox granular sludge to start-up an anammox reactor. PMID:27043054

  2. Anaerobic ammonium oxidation by marine and freshwater planctomycete-like bacteria RID B-8834-2011 RID B-5428-2008 RID C-3269-2011 RID D-1875-2009

    DEFF Research Database (Denmark)

    Jetten, MSM; Sliekers, O.; Kuypers, M.; Dalsgaard, T.; Niftrik, L. van; Cirpus, I.; Pas-Schoonen, K. van de; Lavik, G.; Thamdrup, B.; Paslier, D. Le; Camp, HJM Op den; Hulth, S.; Nielsen, LP; Abma, W.; Third, K.; Engstrom, P.; Kuenen, JG; Jørgensen, BB; Canfield, DE; Damste, JSS; Revsbech, NP; Fuerst, J.; Weissenbach, J.; Wagner, M.; Schmidt, I.; Schmid, M.; Strous, M.

    2003-01-01

    Recently, two fresh water species, 'Candidatus Brocadia anammoxidans' and 'Candidatus Kuenenia stuttgartiensis', and one marine species, 'Candidatus Scalindua sorokinii', of planctomycete anammox bacteria have been identified. 'Candidatus Scalindua sorokinii' was discovered in the Black Sea, and...

  3. Characterization of incubation experiments and development of an enrichment culture capable of ammonium oxidation under iron reducing conditions

    Science.gov (United States)

    Huang, S.; Jaffé, P. R.

    2014-08-01

    Incubation experiments were conducted using soil samples from a forested riparian wetland where we have previously observed anaerobic ammonium oxidation coupled to iron reduction. Production of both nitrite and ferrous iron were measured repeatedly during incubations when the soil slurry was supplied with either ferrihydrite or goethite and ammonium chloride. Significant changes in the microbial community were observed after 180 days of incubation as well as in a continuous flow membrane reactor, using 16S rRNA gene PCR-denaturing gradient gel electrophoresis, 454-pyrosequencing, and real-time quantitative PCR analysis. We believe that one of the dominant microbial species in our system (an uncultured Acidimicrobiaceae bacterium A6), belonging to the Acidimicrobiaceae family, whose closest cultivated relative is Ferrimicrobium acidiphilum (with 92% identity) and Acidimicrobium ferrooxidans (with 90% identity), might play a key role in this anaerobic biological process that uses ferric iron as an electron acceptor while oxidizing ammonium to nitrite. After ammonium was oxidized to nitrite, nitrogen loss proceeded via denitrification and/or anammox.

  4. New Understanding on Metabolism of Anaerobic Ammonium Oxidation Bacteria Based on Metagenomics Technology%基于宏基因组技术获得的对厌氧氨氧化菌代谢的新理解

    Institute of Scientific and Technical Information of China (English)

    丁爽; 郑平; 陆慧锋; 唐崇俭

    2012-01-01

    厌氧氨氧化菌(Anaerobic ammonium oxidation bacteria,AAOB)是化能自养菌,由于其生理代谢的奇异性、细胞结构的特殊性以及对氮素循环的重要性,已成为环境工程、微生物以及海洋生物学等领域的研究热点.然而.AAOB未能实现纯培养的现状已成为AAOB代谢途径研究的巨大障碍近年来兴起的宏基因组技术(Metagenomics)为AAOB代谢途径的研究提供了新手段.采用宏基因组技术,可直接研究微生物群体中某特定微生物基因组的结构与功能,摆脱了传统微生物学研究对纯培养的依赖,使未培养微生物的认识和开发成为可能本文首先简述获取AAOB宏基因组信息的过程,然后通过比较由传统代谢研究方法和宏基因组技术获得的AAOB代谢途径的研究成果,论述基于宏基因组技术获得的对AAOB代谢的新理解,得出以下结果和结论:1)AAOB的碳素固定途径为乙酰辅酶A途径,碳素固定的还原力来自NADH或者QH2;2)AAOB氮素转化的重要中问产物是NO,而非NH2OH,并提出了以NO为核心的AAOB代谢的改进模型;3)AAOB的ATP合成途径为氧化磷酸化,推测的电子传递途径为N2H4-QH2-细胞色素bc1 复合体;细胞色素bc1复合体再将电子用于NO2还原和N2H4合成AAOB的宏基因组技术使AAOB代谢途径的研究更具方向性.随着分子生物学理论和技术的不断发展,宏基因组学的升级技术(如宏转录组学、宏蛋白质组学)将为AAOB代谢途径的研究提供新的方法与平台.%Anaerobic ammonium oxidation bacteria (AAOB) belong to chemolitho-autotrophs. AAOB have become one of the research hotspots in the field of environmental engineering, microbiology and oceanography because of their specificities in metabolism, cell structure and nitrogen cycle. However, AAOB can not been cultivated in pure culture, which has become a great obstacle to study their metabolic pathways in further. Nowadays, fast-developing metagenomics provides

  5. Design and evaluation of universal 16S rRNA gene primers for high-throughput sequencing to simultaneously detect DAMO microbes and anammox bacteria.

    Science.gov (United States)

    Lu, Yong-Ze; Ding, Zhao-Wei; Ding, Jing; Fu, Liang; Zeng, Raymond J

    2015-12-15

    To develop universal 16S rRNA gene primers for high-throughput sequencing for the simultaneous detection of denitrifying anaerobic methane oxidation (DAMO) archaea, DAMO bacteria, and anaerobic ammonium oxidation (anammox) bacteria, four published primer sets (PS2-PS5) were modified. The overall coverage of the four primer pairs was evaluated in silico with the Silva SSU r119 dataset. Based on the virtual evaluation, the two best primer pairs (PS4 and PS5) were selected for further verification. Illumina MiSeq sequencing of a freshwater sediment and a culture from a DAMO-anammox reactor using these two primer pairs revealed that PS5 (341b4F-806R) was the most promising universal primer pair. This pair of primers detected both archaea and bacteria with less bias than PS4. Furthermore, an anaerobic fermentation culture and a wastewater treatment plant culture were used to verify the accuracy of PS5. More importantly, it detected DAMO archaea, DAMO bacteria, and anammox bacteria simultaneously with no false positives appeared. This universal 16S rRNA gene primer pair extends the existing molecular tools for studying the community structures and distributions of DAMO microbes and their potential interactions with anammox bacteria in different environments. PMID:26454634

  6. Anammox for nitrogen removal from anaerobically pre-treated municipal wastewater: Effect of COD/N ratios on process performance and bacterial community structure.

    Science.gov (United States)

    Leal, Cíntia Dutra; Pereira, Alyne Duarte; Nunes, Fernando Terra; Ferreira, Luísa Ornelas; Coelho, Aline Carolina Cirilo; Bicalho, Sarah Kinaip; Mac Conell, Erika F Abreu; Ribeiro, Thiago Bressani; de Lemos Chernicharo, Carlos Augusto; de Araújo, Juliana Calábria

    2016-07-01

    Long-term effects of COD/N ratios on the nitrogen removal performance and bacterial community of an anammox reactor were evaluated by adding a synthetic medium (with glucose) and real anaerobic effluent to a SBR. At a COD/N ratio of 2.8 (COD, 390mg·L(-1)) ammonium removal efficiency was 66%, while nitrite removal remained high (99%). However, at a COD/N ratio of 5.0 (COD, 300mg·L(-1)), ammonium and nitrite removal efficiencies were high (84% and 99%, respectively). High COD, nitrite, and ammonium removal efficiencies (80%, 90% and 95%, respectively) were obtained on adding anaerobically pre-treated municipal wastewater (with nitrite) to the reactor. DGGE revealed that the addition of anaerobic effluent changed the bacterial community structure and selected for DNA sequences related to Brocadia sinica and Chloroflexi. Adding glucose and anaerobic effluent increased denitrifiers concentration threefold. Thus, the possibility of using the anammox process to remove nitrogen from anaerobically pre-treated municipal wastewater was demonstrated. PMID:27023380

  7. Performance evaluation of the anammox hybrid reactor seeded with mixed inoculum sludge.

    Science.gov (United States)

    Tomar, Swati; Gupta, Sunil Kumar; Mishra, Brijesh Kumar

    2016-01-01

    Long startup and poor granulation are the major bottlenecks in field-scale application of the anammox (ANaerobic AMMonium OXidation) process. In the present study, the anammox process was investigated in a modified anammox hybrid reactor (AHR) inoculated with mixed seed culture (anoxic and activated sludge). The startup study delineated four distinct phases, i.e. cell lysis, lag phase, activity elevation and stationary phase. Use of mixed seed culture at influent [Formula: see text] ratio (1:1) and hydraulic retention time (HRT) of 1 d led to early startup of the anammox process. The removal efficiencies of [Formula: see text] and [Formula: see text] during acclimation were found to be 94.3% and 96.4%, respectively, at nitrogen loading rate (NLR) of 0.35 kg N/m(3) d. Pearson correlation analysis dictated strong and positive correlation of HRT and sludge retention time (SRT) with nitrogen removal efficiency (NRE) while NLR and sludge loading rate (SLR) were negatively correlated. Attached growth system (AGS) in AHR contributed an additional 11% ammonium removal and reduced the sludge washout rate by 29%. Mass balance of nitrogen revealed that the major fraction (74.1%) of input nitrogen was converted into N2 gas indicating higher substrate conversion efficiency of anammox biomass. Scanning electron microscope (SEM) study of biomass indicated the presence of heterogeneous population of cocci and rod-shaped bacteria of average diameter varying from 1.2 to 1.5 mm. Owing to the features of early start-up, ability to retain high biomass and consistently higher NRE, hybrid reactor configuration seeded with mixed culture offers noble strategy for cultivation of well-compacted anammox granules for field-scale installation. PMID:26411578

  8. Optimization and Modelling of Chemical Oxygen Demand Removal by ANAMMOX Process Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Ali Jalilzadeh

    2013-01-01

    Full Text Available A systematic model for chemical oxygen demand (COD removal using the ANAMMOX (Anaerobic AMMonium OXidation process was provided based on an experimental design. At first, the experimental data was collected from a combined biological aerobic/anaerobic reactor. For modelling and optimization of COD removal, the main parameters were considered, such as COD loading, ammonium, pH, and temperature. From the models, the optimum conditions were determined as COD 97.5 mg/L, ammonium concentration equal to 28.75 mg-N/L, pH 7.72, and temperature 31.3°C. Finally, the analysis of the optimum conditions, performed by the response surface method, predicted COD removal efficiency of 81.07% at the optimum condition.

  9. Effect of Different Filling Materials in Anammox Bacteria Enrichment

    Directory of Open Access Journals (Sweden)

    Dilek ÖZGÜN

    2012-12-01

    Full Text Available Purpose: Anaerobic ammonium oxidation (Anammox is a process that ammonium as electron donor is oxidized to nitrogen gas using nitrite as electron acceptor. Compared to conventional nitrification-denitrification processes, this process is used less oxygen and no organic material (methanol, glucose. However, the slow growth rate of Anammox bacteria (11-30 days is disadvantages. Therefore, batch reactors have been carried out in these bacteria enrichment. In this study continuously operated upflow anaerobic sludge reactor (UASB using different filling materials disposing of sensitive and slow-growing Anammox bacteria out of the system is purposed. Design and Methods: System is operated up-flow column reactor at 2 days hydraulic retention time (HRT in 45 days. In this study, ceramic stones and Linpor filling material are used. Using synthetic wastewater containing ammonium and nitrite, Ar/CO2 anaerobic conditions (95/5% supplied with gas. System is operated at a temperature 253 C in UASB. Temperature, pH, ammonia-nitrogen and nitrite nitrogen are measured. Results: Both filling material reactors are operated in 45 days. Ceramic stones filling reactor is observed quickly reaches 90% were used reactor ammonium removal. The ammonium nitrogen removal was slower in Linpor filling materials reactor. Nitrite removal is reached up to 90% in both the reactor. When compared to the stoichiometric equation in Linpor was composed of large amounts of nitrate. At the end of 25 days the results were similar to ceramic stone filling reactor with Linpor filling material reactors. Conclusions and Original Value: Anammox process as from nitrogen removal processes was discovered in 1995. Anammox bacteria that make up this process due to very low growth rates of microbial bacteria in the system must be kept in the system. Most of the studies in the literature, these bacteria enrichment stage is started instead of a continuous batch reactor system. In this study

  10. Distribution and activity of anaerobic ammonium-oxidising bacteria in natural freshwater wetland soils.

    Science.gov (United States)

    Shen, Li-dong; Wu, Hong-sheng; Gao, Zhi-qiu; Cheng, Hai-xiang; Li, Ji; Liu, Xu; Ren, Qian-qi

    2016-04-01

    Anaerobic ammonium oxidation (anammox) process plays a significant role in the marine nitrogen cycle. However, the quantitative importance of this process in nitrogen removal in wetland systems, particularly in natural freshwater wetlands, is still not determined. In the present study, we provided the evidence of the distribution and activity of anammox bacteria in a natural freshwater wetland, located in southeastern China, by using (15)N stable isotope measurements, quantitative PCR assays and 16S rRNA gene clone library analysis. The potential anammox rates measured in this wetland system ranged between 2.5 and 25.5 nmol N2 g(-1) soil day(-1), and up to 20% soil dinitrogen gas production could be attributed to the anammox process. Phylogenetic analysis of 16S rRNA genes showed that anammox bacteria related to Candidatus Brocadia, Candidatus Kuenenia, Candidatus Anammoxoglobus and two novel anammox clusters coexisted in the collected soil cores, with Candidatus Brocadia and Candidatus Kuenenia being the dominant anammox genera. Quantitative PCR of hydrazine synthase genes showed that the abundance of anammox bacteria varied from 2.3 × 10(5) to 2.2 × 10(6) copies g(-1) soil in the examined soil cores. Correlation analyses suggested that the soil ammonium concentration had significant influence on the activity of anammox bacteria. On the basis of (15)N tracing technology, it is estimated that a total loss of 31.1 g N m(-2) per year could be linked the anammox process in the examined wetland. PMID:26621804

  11. [Start-up of a full-scale system for short-cut nitrification and Anammox in treatment of pharmaceutical wastewater].

    Science.gov (United States)

    Ding, Shuang; Zheng, Ping; Zhang, Zonghe; Lu, Huifeng; Zhang, Meng; Wu, Datian; Wu, Zegao

    2014-12-01

    In order to broaden the application area of the new nitrogen removal technology, a full-scale system for short-cut nitrification and anaerobic ammonium oxidation (Anammox) was investigated in the nitrogen removal from a strong-ammonium pharmaceutical wastewater. When the influent ammonium concentration was (430.40 ± 55.43) mg/L, ammonia removal efficiency was (81.75 ± 9.10)%. The short-cut nitrification and Anammox system could successfully remove nitrogen from the pharmaceutical wastewater. The start-up of short-cut nitrification system took about 74 d and the nitrite accumulation efficiency was (52.11 ± 9.13)%, the two-step mode using synthetic wastewater and actual wastewater was suitable for the start-up of short-cut nitrification system. The start-up of Anammox system took about 145 d and the maximum volumetric nitrogen removal rate was 6.35 kg N/(m3·d), dozens of times higher than those for the conventional nitrification-denitrification process. The strategy achieving Anammox sludge by self-growth and biocatalyst addition was suitable for the start-up of Anammox system. PMID:26016378

  12. Denitrification and anammox in tropical aquaculture settlement ponds: an isotope tracer approach for evaluating N2 production.

    Science.gov (United States)

    Castine, Sarah A; Erler, Dirk V; Trott, Lindsay A; Paul, Nicholas A; de Nys, Rocky; Eyre, Bradley D

    2012-01-01

    Settlement ponds are used to treat aquaculture discharge water by removing nutrients through physical (settling) and biological (microbial transformation) processes. Nutrient removal through settling has been quantified, however, the occurrence of, and potential for microbial nitrogen (N) removal is largely unknown in these systems. Therefore, isotope tracer techniques were used to measure potential rates of denitrification and anaerobic ammonium oxidation (anammox) in the sediment of settlement ponds in tropical aquaculture systems. Dinitrogen gas (N(2)) was produced in all ponds, although potential rates were low (0-7.07 nmol N cm(-3) h(-1)) relative to other aquatic systems. Denitrification was the main driver of N(2) production, with anammox only detected in two of the four ponds. No correlations were detected between the measured sediment variables (total organic carbon, total nitrogen, iron, manganese, sulphur and phosphorous) and denitrification or anammox. Furthermore, denitrification was not carbon limited as the addition of particulate organic matter (paired t-Test; P = 0.350, n = 3) or methanol (paired t-Test; P = 0.744, n = 3) did not stimulate production of N(2). A simple mass balance model showed that only 2.5% of added fixed N was removed in the studied settlement ponds through the denitrification and anammox processes. It is recommended that settlement ponds be used in conjunction with additional technologies (i.e. constructed wetlands or biological reactors) to enhance N(2) production and N removal from aquaculture wastewater. PMID:22962581

  13. Kinetics of nitrogen removal in high rate anammox upflow filter

    International Nuclear Information System (INIS)

    The process kinetics for laboratory-scale anammox (anaerobic ammonium oxidation) upflow filter using synthetic wastewater as feed were investigated. The experimental unit consisted of a 2.0 L reactor filled with three-dimensional plastic media. The filter was tested for different influent substrate concentrations and hydraulic retention time (HRT). The substrate loading removal rate was compared with prediction of Stover-Kincannon, second-order and the first-order substrate removal models. Upon approaching pseudo-steady-state condition, substrate ammonium or nitrite concentrations were increased from 280 to 462 mg N/L, while HRT was stepwise decreased from 14.4 to 2 h, with a concomitant increase in nitrogen loading rate (NLR) from 0.93 to 7.34 g/L day. Based on calculations, Stover-Kincannon model and second-order 'Grau' model were found to be the appropriate models to describe the upflow filter. According to Stover-Kincannon model, the maximum total substrate removal rate constant (Umax) and saturation value constant (KB) were suggested as 12.4 and 12.0 g N/L day, respectively. As Stover-Kincannon model and second-order model gave high correlation coefficients (97.9% and 98.6%, respectively), these models may be used in predicting the behavior or design of the anammox filter.

  14. Fate of hormones and pharmaceuticals during combined anaerobic treatment and nitrogen removal by partial nitritation-anammox in vacuum collected black water.

    Science.gov (United States)

    de Graaff, M S; Vieno, N M; Kujawa-Roeleveld, K; Zeeman, G; Temmink, H; Buisman, C J N

    2011-01-01

    Vacuum collected black (toilet) water contains hormones and pharmaceuticals in relatively high concentrations (μg/L to mg/L range) and separate specific treatment has the potential of minimizing their discharge to surface waters. In this study, the fate of estrogens (natural and synthetical hormones) and pharmaceuticals (paracetamol, metoprolol, propranolol, cetirizine, doxycycline, tetracycline, ciprofloxacin, trimethoprim, carbamazepine, ibuprofen and diclofenac) in the anaerobic treatment of vacuum collected black water followed by nitrogen removal by partial nitritation-anammox was investigated. A new analytical method was developed to detect the presence of several compounds in the complex matrix of concentrated black water. Detected concentrations in black water ranged from 1.1 μg/L for carbamazepine to >1000 μg/L for paracetamol. Anaerobic treatment was only suitable to remove the majority of paracetamol (>90%). Metoprolol was partly removed (67%) during aerobic treatment. Deconjugation could have affected the removal efficiency of ibuprofen as concentrations even increased during anaerobic treatment and only after the anammox treatment 77% of ibuprofen was removed. The presence of persistent micro-pollutants (diclofenac, carbamazepine and cetirizine), which are not susceptible for biodegradation, makes the application of advanced physical and chemical treatment unavoidable. PMID:20832097

  15. Seasonal dynamics of ammonia/ammonium-oxidizing prokaryotes in oxic and anoxic wetland sediments of subtropical coastal mangrove

    OpenAIRE

    Wang, Yong-Feng; Feng, Yao-Yu; Ma, Xiaojun; Gu, Ji-Dong

    2012-01-01

    Mangrove wetlands are an important ecosystem in tropical and subtropical regions, and the sediments may contain both oxic and anoxic zones. In this study, ammonia/ammonium-oxidizing prokaryotes (AOPs) in yellow and black sediments with vegetation and non-vegetated sediments in a mangrove wetland of subtropical Hong Kong were investigated in winter and summer. The phylogenetic diversity of anammox bacterial 16S rRNA genes and archaeal and bacterial amoA genes (encoding ammonia monooxygenase al...

  16. Semi-nitritation process producing optimum influent for anammox process in treatment of domestic wastewater.

    Science.gov (United States)

    Tang, Xiaoxue; Yang, Qing; Li, Jianlin; Peng, Yongzhen; Xu, Zhubing; He, Jianzhong

    2016-06-01

    The process of anaerobic ammonium oxidation (Anammox) requires a proper ratio of NH4(+)-N and NO2(-)-N in the influent, which is difficult to control upon treating domestic wastewater. In this study, a control strategy of semi-nitritation (SN) process based on monitoring the pH profile and NH4(+)-N concentration in a sequencing batch reactor (SBR) was developed. The aeration time of each cycle in SN-SBR was calculated using the established equation tSN=tCOD+0.56αnS0/(S0-Sn). To verify the suitability of the control strategy, SN-SBR was operated continuously for 20 cycles, fed with real domestic wastewater with a fluctuating COD of 200-400 mg L(-1) and NH4(+)-N of 65-80 mg L(-1). The nitrogen removal performance of SN-anammox system using the developed control strategy was also monitored. Results showed that SN-SBR was able to generate a suitable ratio of NH4(+)-N to NO2(-)-N for the following anammox process, the TN removal rate of the SN-anammox system achieved 91.7 ± 0.4% and the average ammonium, nitrite and nitrate concentration of effluent was only 0.50 ± 0.24, 0.13 ± 0.09 and 4.9 ± 0.22 mg L(-1), respectively. This study has potential application in the treatment of domestic wastewater using combined SN-anammox process. PMID:26963236

  17. Anammox bacteria community and nitrogen removal in a strip-like wetland in the riparian zone.

    Science.gov (United States)

    Pei, Yuansheng; Wang, Jun; Wang, Ziyuan; Tian, Binghui

    2011-01-01

    A strip-like wetland was constructed in the riparian zone for investigation of ammonium nitrogen (NH(3)-N) removal in the Peach River. An inner zeolite layer was set in the wetland to adsorb NH(3)-N and further to remove total nitrogen (TN). An oxygen-deficient condition with dissolved oxygen of 0.87-1.60 mg L(-1) was observed in the zeolite layer, which benefits anaerobic ammonium oxidation (anammox) bacteria survival. The community structure of anammox bacteria was analyzed in the zeolite layer. The analysis shows that the anammox bacterial sequences are grouped into three known distinct clusters: Candidatus Brocadia fulgida, Candidatus Brocadia anammoxidans and Candidatus Jettenia asiatica. The intensified test driven by artificial pumping shows that average removal rates of NH(3)-N and TN are 41.6 mg m(-3)d(-1) and 63.2 mg m(-3)d(-1), respectively. The normal test driven by natural hydrodynamics also verifies that NH(3)-N removal mainly happens in the zeolite layer. Microbial mechanism of TN removal in the wetland involves both the autotrophic and heterotrophic process. These results suggest that the strip-like RW can be a cost-effective approach for NH(3)-N removal and can potentially be extended to similar rivers as no extra energy is required to maintain the wetland operation. PMID:21644147

  18. Sustainable operation of submerged Anammox membrane bioreactor with recycling biogas sparging for alleviating membrane fouling.

    Science.gov (United States)

    Li, Ziyin; Xu, Xindi; Xu, Xiaochen; Yang, FengLin; Zhang, ShuShen

    2015-12-01

    A submerged anaerobic ammonium oxidizing (Anammox) membrane bioreactor with recycling biogas sparging for alleviating membrane fouling has been successfully operated for 100d. Based on the batch tests, a recycling biogas sparging rate at 0.2m(3)h(-1) was fixed as an ultimate value for the sustainable operation. The mixed liquor volatile suspended solid (VSS) of the inoculum for the long operation was around 3000mgL(-1). With recycling biogas sparging rate increasing stepwise from 0 to 0.2m(3)h(-1), the reactor reached an influent total nitrogen (TN) up to 1.7gL(-1), a stable TN removal efficiency of 83% and a maximum specific Anammox activity (SAA) of 0.56kg TNkg(-1) VSSd(-1). With recycling biogas sparging rate at 0.2 m(3) h(-1) (corresponding to an aeration intensity of 118m(3)m(-2)h(-1)), the membrane operation circle could prolong by around 20 times compared to that without gas sparging. Furthermore, mechanism of membrane fouling was proposed. And with recycling biogas sparging, the VSS and EPS content increasing rate in cake layer were far less than the ones without biogas sparging. The TN removal performance and sustainable membrane operation of this system showed the appealing potential of the submerged Anammox MBR with recycling biogas sparging in treating high-strength nitrogen-containing wastewaters. PMID:25311769

  19. Achieving complete nitrogen removal by coupling nitritation-anammox and methane-dependent denitrification: A model-based study.

    Science.gov (United States)

    Chen, Xueming; Guo, Jianhua; Xie, Guo-Jun; Yuan, Zhiguo; Ni, Bing-Jie

    2016-05-01

    The discovery of denitrifying anaerobic methane oxidation (DAMO) processes enables the complete nitrogen removal from wastewater by utilizing the methane produced on site from anaerobic digesters. This model-based study investigated the mechanisms and operational window for efficient nitrogen removal by coupling nitritation-anaerobic ammonium oxidation (Anammox) and methane-dependent denitrification in membrane biofilm reactors (MBfRs). A mathematical model was applied to describe the microbial interactions among Anammox bacteria, DAMO archaea, and DAMO bacteria. The model sufficiently described the batch experimental data from an MBfR containing an Anammox-DAMO biofilm with different feeding nitrogen compositions, which confirmed the validity of the model. The effects of process parameters on the system performance and microbial community structure could therefore be reliably evaluated. The impacts of nitritation produced NO2 (-) /NH4 (+) ratio, methane supply, biofilm thickness and total nitrogen (TN) surface loading were comprehensively investigated with the model. Results showed that the optimum NO2 (-) /NH4 (+) ratio produced from nitritation for the Anammox-DAMO biofilm system was around 1.0 in order to achieve the maximum TN removal (over 99.0%), independent on TN surface loading. The corresponding optimal methane supply increased while the associated methane utilization efficiency decreased with the increase of TN surface loading. The cooperation between DAMO organisms and Anammox bacteria played the key role in the TN removal. Based on these results, the proof-of-concept feasibility of a single-stage MBfR coupling nitritation-Anammox-DAMO for complete nitrogen removal was also tested through integrating the model with ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) processes whilst controlling the dissolved oxygen (DO) concentration in the simulated system. The maximum TN removal was found to be achieved at the bulk DO concentration

  20. Shotgun metagenomic data reveals signifcant abundance but low diversity of Candidatus Scalindua marine anammox bacteria in the Arabian Sea oxygen minimum zone

    Directory of Open Access Journals (Sweden)

    laura eVillanueva

    2014-02-01

    Full Text Available Anaerobic ammonium oxidizing (anammox bacteria are responsible for a significant portion of the loss of fixed nitrogen from the oceans, making them important players in the global nitrogen cycle. To date, marine anammox bacteria found in both water columns and sediments worldwide belong almost exclusively to Candidatus Scalindua species. Recently the genome assembly of a marine anammox enrichment culture dominated by Candidatus Scalindua profunda became available and can now be used as a template to study metagenome data obtained from various oxygen minimum zones. Here, we sequenced genomic DNA from suspended particulate matter recovered at the upper (170 m deep and center (600 m area of the oxygen minimum zone in the Arabian Sea by SOLiD and Ion Torrent technology. The genome of Candidatus Scalindua profunda served as a template to collect reads. Based on the mapped reads marine anammox Abundance was estimated to be at least 0.4% in the upper and 1.7% in the center area. Single nucleotide variation (SNV analysis was performed to assess diversity of the Candidatus Scalindua populations. Most highly covered were the two diagnostic anammox genes hydrazine synthase (scal_01318c, hzsA and hydrazine dehydrogenase (scal_03295, hdh, while other genes involved in anammox metabolism (narGH, nirS, amtB, focA and ACS had a lower coverage but could still be assembled and analyzed. The results show that Candidatus Scalindua is abundantly present in the Arabian Sea OMZ, but that the diversity within the ecosystem is relatively low.

  1. Model-Based Feasibility Assessment of Membrane Biofilm Reactor to Achieve Simultaneous Ammonium, Dissolved Methane, and Sulfide Removal from Anaerobic Digestion Liquor.

    Science.gov (United States)

    Chen, Xueming; Liu, Yiwen; Peng, Lai; Yuan, Zhiguo; Ni, Bing-Jie

    2016-01-01

    In this study, the membrane biofilm reactor (MBfR) is proposed to achieve simultaneous removal of ammonium, dissolved methane, and sulfide from main-stream and side-stream anaerobic digestion liquors. To avoid dissolved methane stripping, oxygen is introduced through gas-permeable membranes, which also from the substratum for the growth of a biofilm likely comprising ammonium oxidizing bacteria (AOB), anaerobic ammonium oxidation (Anammox) bacteria, denitrifying anaerobic methane oxidation (DAMO) microorganisms, aerobic methane oxidizing bacteria (MOB), and sulfur oxidizing bacteria (SOB). A mathematical model is developed and applied to assess the feasibility of such a system and the associated microbial community structure under different operational conditions. The simulation studies demonstrate the feasibility of achieving high-level (>97.0%), simultaneous removal of ammonium, dissolved methane, and sulfide in the MBfRs from both main-stream and side-stream anaerobic digestion liquors through adjusting the influent surface loading (or hydraulic retention time (HRT)) and the oxygen surface loading. The optimal HRT was found to be inversely proportional to the corresponding oxygen surface loading. Under the optimal operational conditions, AOB, DAMO bacteria, MOB, and SOB dominate the biofilm of the main-stream MBfR, while AOB, Anammox bacteria, DAMO bacteria, and SOB coexist in the side-stream MBfR to remove ammonium, dissolved methane, and sulfide simultaneously. PMID:27112502

  2. Model-Based Feasibility Assessment of Membrane Biofilm Reactor to Achieve Simultaneous Ammonium, Dissolved Methane, and Sulfide Removal from Anaerobic Digestion Liquor

    Science.gov (United States)

    Chen, Xueming; Liu, Yiwen; Peng, Lai; Yuan, Zhiguo; Ni, Bing-Jie

    2016-04-01

    In this study, the membrane biofilm reactor (MBfR) is proposed to achieve simultaneous removal of ammonium, dissolved methane, and sulfide from main-stream and side-stream anaerobic digestion liquors. To avoid dissolved methane stripping, oxygen is introduced through gas-permeable membranes, which also from the substratum for the growth of a biofilm likely comprising ammonium oxidizing bacteria (AOB), anaerobic ammonium oxidation (Anammox) bacteria, denitrifying anaerobic methane oxidation (DAMO) microorganisms, aerobic methane oxidizing bacteria (MOB), and sulfur oxidizing bacteria (SOB). A mathematical model is developed and applied to assess the feasibility of such a system and the associated microbial community structure under different operational conditions. The simulation studies demonstrate the feasibility of achieving high-level (>97.0%), simultaneous removal of ammonium, dissolved methane, and sulfide in the MBfRs from both main-stream and side-stream anaerobic digestion liquors through adjusting the influent surface loading (or hydraulic retention time (HRT)) and the oxygen surface loading. The optimal HRT was found to be inversely proportional to the corresponding oxygen surface loading. Under the optimal operational conditions, AOB, DAMO bacteria, MOB, and SOB dominate the biofilm of the main-stream MBfR, while AOB, Anammox bacteria, DAMO bacteria, and SOB coexist in the side-stream MBfR to remove ammonium, dissolved methane, and sulfide simultaneously.

  3. Model-Based Feasibility Assessment of Membrane Biofilm Reactor to Achieve Simultaneous Ammonium, Dissolved Methane, and Sulfide Removal from Anaerobic Digestion Liquor

    Science.gov (United States)

    Chen, Xueming; Liu, Yiwen; Peng, Lai; Yuan, Zhiguo; Ni, Bing-Jie

    2016-01-01

    In this study, the membrane biofilm reactor (MBfR) is proposed to achieve simultaneous removal of ammonium, dissolved methane, and sulfide from main-stream and side-stream anaerobic digestion liquors. To avoid dissolved methane stripping, oxygen is introduced through gas-permeable membranes, which also from the substratum for the growth of a biofilm likely comprising ammonium oxidizing bacteria (AOB), anaerobic ammonium oxidation (Anammox) bacteria, denitrifying anaerobic methane oxidation (DAMO) microorganisms, aerobic methane oxidizing bacteria (MOB), and sulfur oxidizing bacteria (SOB). A mathematical model is developed and applied to assess the feasibility of such a system and the associated microbial community structure under different operational conditions. The simulation studies demonstrate the feasibility of achieving high-level (>97.0%), simultaneous removal of ammonium, dissolved methane, and sulfide in the MBfRs from both main-stream and side-stream anaerobic digestion liquors through adjusting the influent surface loading (or hydraulic retention time (HRT)) and the oxygen surface loading. The optimal HRT was found to be inversely proportional to the corresponding oxygen surface loading. Under the optimal operational conditions, AOB, DAMO bacteria, MOB, and SOB dominate the biofilm of the main-stream MBfR, while AOB, Anammox bacteria, DAMO bacteria, and SOB coexist in the side-stream MBfR to remove ammonium, dissolved methane, and sulfide simultaneously. PMID:27112502

  4. Co-occurrence of nitrite-dependent anaerobic ammonium and methane oxidation processes in subtropical acidic forest soils.

    Science.gov (United States)

    Meng, Han; Wang, Yong-Feng; Chan, Ho-Wang; Wu, Ruo-Nan; Gu, Ji-Dong

    2016-09-01

    Anaerobic ammonium oxidation (anammox) and nitrite-dependent anaerobic methane oxidation (n-damo) are two new processes of recent discoveries linking the microbial nitrogen and carbon cycles. In this study, 16S ribosomal RNA (rRNA) gene of anammox bacteria and pmoA gene of n-damo bacteria were used to investigate their distribution and diversity in natural acidic and re-vegetated forest soils. The 16S rRNA gene sequences retrieved featured at least three species in two genera known anammox bacteria, namely Candidatus Brocadia anammoxidans, Candidatus Brocadia fulgida, and Candidatus Kuenenia stuttgartiensis while the pmoA gene amplified was affiliated with two species of known n-damo bacteria Candidatus Methylomirabilis oxyfera and a newly established Candidatus Methylomirabilis sp. According to the results, the diversity of anammox bacteria in natural forests was lower than in re-vegetated forests, but no significant difference was observed in n-damo community between them. Quantitative real-time PCR showed that both anammox and n-damo bacteria were more abundant in the lower layer (10-20 cm) than the surface layer (0-5 cm). The abundance of anammox bacteria varied from 2.21 × 10(5) to 3.90 × 10(6) gene copies per gram dry soil, and n-damo bacteria quantities were between 1.69 × 10(5) and 5.07 × 10(6) gene copies per gram dry soil in the two different layers. Both anammox and n-damo bacteria are reported for the first time to co-occur in acidic forest soil in this study, providing a more comprehensive information on more defined microbial processes contributing to C and N cycles in the ecosystems. PMID:27178181

  5. Autotrophic ammonia removal from landfill leachate in anaerobic membrane bioreactor.

    Science.gov (United States)

    Suneethi, S; Joseph, Kurian

    2013-01-01

    Anaerobic ammonium oxidation (ANAMMOX) process, an advanced biological nitrogen removal, removes ammonia using nitrite as the electron acceptor without oxygen. In this paper, ANAMMOX process was adopted for removing NH4+-N from landfill leachate having low COD using anaerobic membrane bioreactor (AnMBR). The AnMBR was optimized for nitrogen loading rate (NLR) varying from 0.025 to 5 kg NH4+-N/m3/d with hydraulic retention time (HRT) ranging from 1 to 3d. NH4+-N removal efficacy of 85.13 +/- 9.67% with the mean nitrogen removal rate of 5.54 +/- 0.63 kg NH4+-N/m3/d was achieved with NLR of 6.51 +/- 0.20kg NH4+-N/m3/d at 1.5 d HRT. The nitrogen transformation intermediates in the form of hydrazine (N2H4) and hydroxylamine (NH2OH) were 0.008 +/- 0.005 and 0.006 +/- 0.001 mg/l, respectively, indicating co-existence of aerobic ammonia oxidizers and ANAMMOX. The free ammonia (NH3) and free nitrous acid (HNO2) concentrations were 26.61 +/- 16.54 mg/l and (1.66 +/- 0.95) x 10(-5) mg/l, preventing NO2(-)-N oxidation to NO3(-)-N enabling sustained NH4+-N removal. PMID:24617075

  6. Presence and diversity of anammox bacteria in cold hydrocarbon-rich seeps and hydrothermal vent sediments of the Guaymas Basin

    Directory of Open Access Journals (Sweden)

    Lina eRuss

    2013-08-01

    Full Text Available Hydrothermally active sediments are highly productive, chemosynthetic areas which are characterized by the rapid turnover of particulate organic matter under extreme conditions in which ammonia is liberated. These systems might be suitable habitats for anaerobic ammonium oxidizing (anammox bacteria but this has not been investigated in detail. Here we report the diversity and abundance of anammox bacteria in sediments that seep cold hydrocarbon-rich fluids and hydrothermal vent areas of the Guaymas Basin in the Cortés Sea using the unique functional anammox marker gene, hydrazine synthase (hzsA. All clones retrieved were closely associated to the ‘Candidatus Scalindua’ genus. Phylogenetic analysis revealed two distinct clusters of hzsA sequences (Ca. Scalindua hzsA cluster I and II. Comparison of individual sequences from both clusters showed that several of these sequences had a similarity as low as 76% on nucleotide level. Based on the analysis of this phylomarker, a very high interspecies diversity within the marine anammox group is apparent. Absolute numbers of anammox bacteria in the sediments samples were determined by amplification of a 257 bp fragment of the hszA gene in a qPCR assay. The results indicate that numbers of anammox bacteria are generally higher in cold hydrocarbon-rich sediments compared to the vent areas and the reference zone. Ladderanes, lipids unique to anammox bacteria were also detected in several of the sediment samples corroborating the hzsA analysis. Due to the high concentrations of reduced sulfur compounds and its potential impact on the cycling of nitrogen we aimed to get an indication about the key players in the oxidation of sulfide in the Guaymas Basin sediments using the alpha subunit of the adenosine-5’-phosphosulfate (APS reductase (aprA. Amplification of the aprA gene revealed a high number of gammaproteobacterial aprA genes covering the two sulfur-oxidizing bacteria aprA lineages as well as

  7. DEAMOX--new biological nitrogen removal process based on anaerobic ammonia oxidation coupled to sulphide-driven conversion of nitrate into nitrite.

    Science.gov (United States)

    Kalyuzhnyi, Sergey; Gladchenko, Marina; Mulder, Arnold; Versprille, Bram

    2006-11-01

    This paper reports about the successful laboratory testing of a new nitrogen removal process called DEAMOX (DEnitrifying AMmonium OXidation) for treatment of typical strong nitrogenous wastewater such as baker's yeast effluent. The concept of this process combines the recently discovered anammox (anaerobic ammonium oxidation) reaction with autotrophic denitrifying conditions using sulphide as an electron donor for the production of nitrite from nitrate within an anaerobic biofilm. To generate sulphide and ammonia, a Upflow Anaerobic Sludge Bed (UASB) reactor was used as a pre-treatment step. The UASB effluent was split and partially fed to a nitrifying reactor (to generate nitrate) and the remaining part was directly fed to the DEAMOX reactor where this stream was mixed with the nitrified effluent. Stable process performance and volumetric nitrogen loading rates of the DEAMOX reactor well above 1000 mgN/l/d with total nitrogen removal efficiencies of around 90% were obtained after long-term (410 days) optimisation of the process. Important prerequisites for this performance are appropriate influent ratios of the key species fed to the DEAMOX reactor, namely influent N-NO(x)/N-NH(4) ratios >1.2 (stoichiometry of the anammox reaction) and influent S-H(2)S/N-NO(3) ratios >0.57 mgS/mgN (stoichiometry of the sulphide-driven denitrification of nitrate to nitrite). The paper further describes some characteristics of the DEAMOX sludge as well as the preliminary results of its microbiological characterisation. PMID:16893559

  8. Start-up of the anammox process from the conventional activated sludge in a hybrid bioreactor

    Institute of Scientific and Technical Information of China (English)

    Xiumei Duan; Jiti Zhou; Sen Qiao; Xin Yin; Tian Tian; Fangdi Xu

    2012-01-01

    The anaerobic ammonium oxidation (anammox) process was successfully started up from conventional activated sludge using a hybrid bioreactor within 2 months.The average removal efficiencies of ammonia and nitrite were both over 80%,and the maximum total nitrogen removal rate of 1.85 kg1 N/(m3·day) was obtained on day 362 with the initial sludge concentration of 0.7 g mixed liquor suspended solids (MLSS)/L.Scanning electron microscope (SEM) observation of the granular sludge in the hybrid reactor clearly showed a high degree of compactness and cell sphericity,and the cell size was quite uniform.Transmission electron microscope photos showed that cells were round or oval,the cellular diameter was 0.6-1.0 μm,and the percentage of the anammoxosome compartment was 51%-85% of the whole cell volume.Fluorescence in situ hybridization analysis (FISH) indicated that anammox bacteria became the dominant population in the community (accounting for more than 51% of total bacteria on day 250).Seven planctomycete 16S rRNA gene sequences were present in the 16S rRNA gene clone library generated from the biomass and affiliated to Candidatus Kuenenia stuttgartiensis and Candidatus Brocadia sp.,a new anammox species.In addition,the average effluent suspended solid (MLSS) concentrations of outlets Ⅰ (above the non-woven carrier) and Ⅱ (below the non-woven carrier) were 0.0009 and 0.0035 g/L,respectively.This showed that the non-woven carrier could catch the biomass effectively,which increased biomass and improved the nitrogen removal rate in the reactor.

  9. Transient and long-term effects of bicarbonate on the ANAMMOX process.

    Science.gov (United States)

    Jin, Ren-Cun; Yu, Jin-Jin; Ma, Chun; Yang, Guang-Feng; Zhang, Jue; Chen, Hui; Zhang, Qian-Qian; Ji, Yu-Xin; Hu, Bao-Lan

    2014-02-01

    In this study, the effects of both transient and long-term inorganic carbon (IC) addition on the anaerobic ammonium oxidation (ANAMMOX) process under pseudo-steady-state and substrate inhibitions were analyzed using reactor performance and measures of sludge activity. Compared with the nitrogen removal rate (NRR) of 3.42 kg N m(-3) day(-1) in the control bioreactor (ICDR) without IC, the peak NRR reached 21.0 kg N m(-3) day(-1) in the reactor (ICAR) with sufficient IC added. It was revealed that the long-term addition of bicarbonate significantly enhanced the performance of the ANAMMOX reactor. The optimum HCO3 (-)/TN ratio was considered to be 1.20, which is lower than that in normal conditions. The IC concentration affected biomass activity, and the transient addition or removal of IC to differing sludge media caused a significant loss of activity. Sufficient addition of IC alleviated the inhibition of excess substrates, while the inhibition was aggravated by the IC limitation. The half-maximal (50 %) inhibitory concentrations of substrate for the sludge were 295 mg L(-1) NO2 (-)-N and 361 mg L(-1) NH4 (+)-N with 120 mg L(-1) of fixed HCO3 (-) and 346 mg L(-1) NO2 (-)-N and 456 mg L(-1) NH4 (+)-N with unlimited IC, respectively. Changing the HCO3 (-)/TN (in milligrams per milligram) ratio resulted in the variation of ANAMMOX stoichiometric ratios. Sludge characterization parameters in the ICDR, including biomass, extracellular polymeric substances, heme C, and so on, were lower than those in ICAR. Filamentous bacteria and spherical bacteria were also observed in the reactor with limited IC. PMID:23780583

  10. The ANAMMOX reactor under transient-state conditions: process stability with fluctuations of the nitrogen concentration, inflow rate, pH and sodium chloride addition.

    Science.gov (United States)

    Yu, Jin-Jin; Jin, Ren-Cun

    2012-09-01

    The process stability of an anaerobic ammonium oxidation (ANAMMOX) was investigated in an upflow anaerobic sludge blanket reactor subjected to overloads of 2.0- to 3.0-fold increases in substrate concentrations, inflow rates lasting 12 or 24h, extreme pH levels of 4 and 10 for 12h and a 12-h 30 g l(-1) NaCl addition. During the overloads, the nitrogen removal rate improved, and the shock period was an important factor affecting the reactor performance. In the high pH condition, the reactor performance significantly degenerated; while in the low pH condition, it did not happen. The NaCl addition caused the most serious deterioration in the reactor, which took 108 h to recover and was accompanied by a stoichiometric ratio divergence. There are well correlations between the total nitrogen and the electrical conductivity which is considered to be a convenient signal for controlling and monitoring the ANAMMOX process under transient-state conditions. PMID:22728197

  11. Nitrate reduction by denitrifying anaerobic methane oxidizing microorganisms can reach a practically useful rate.

    Science.gov (United States)

    Cai, Chen; Hu, Shihu; Guo, Jianhua; Shi, Ying; Xie, Guo-Jun; Yuan, Zhiguo

    2015-12-15

    Methane in biogas has been proposed to be an electron donor to facilitate complete nitrogen removal using denitrifying anaerobic methane oxidizing (DAMO) microorganisms in an anaerobic ammonium oxidation (anammox) reactor, by reducing the nitrate produced. However, the slow growth and the low activity of DAMO microorganisms cast a serious doubt about the practical usefulness of such a process. In this study, a previously established lab-scale membrane biofilm reactor (MBfR), with biofilms consisting of a coculture of DAMO and anammox microorganisms, was operated to answer if the DAMO reactor can achieve a nitrate reduction rate that can potentially be applied for wastewater treatment. Through progressively increasing nitrate and ammonium loading rates to the reactor, a nitrate removal rate of 684 ± 10 mg-N L(-1) d(-1) was achieved after 453 days of operation. This rate is, to our knowledge, by far the highest reported for DAMO reactors, and far exceeds what is predicted to be required for nitrate removal in a sidestream (5.6-135 mg-N L(-1) d(-1)) or mainstream anammox reactor (3.2-124 mg-N L(-1) d(-1)). Mass balance analysis showed that the nitrite produced by nitrate reduction was jointly reduced by anammox bacteria at a rate of 354 ± 3 mg-N L(-1) d(-1), accompanied by an ammonium removal rate of 268 ± 2 mg-N L(-1) d(-1), and DAMO bacteria at a rate of 330 ± 9 mg-N L(-1) d(-1). This study shows that the nitrate reduction rate achieved by the DAMO process can be high enough for removing nitrate produced by anammox process, which would enable complete nitrogen removal from wastewater. PMID:26414889

  12. Mainstream partial nitritation and anammox: long-term process stability and effluent quality at low temperatures.

    Science.gov (United States)

    Laureni, Michele; Falås, Per; Robin, Orlane; Wick, Arne; Weissbrodt, David G; Nielsen, Jeppe Lund; Ternes, Thomas A; Morgenroth, Eberhard; Joss, Adriano

    2016-09-15

    The implementation of autotrophic anaerobic ammonium oxidation processes for the removal of nitrogen from municipal wastewater (known as "mainstream anammox") bears the potential to bring wastewater treatment plants close to energy autarky. The aim of the present work was to assess the long-term stability of partial nitritation/anammox (PN/A) processes operating at low temperatures and their reliability in meeting nitrogen concentrations in the range of typical discharge limits below 2  [Formula: see text] and 10 mgNtot·L(-1). Two main 12-L sequencing batch reactors were operated in parallel for PN/A on aerobically pre-treated municipal wastewater (21 ± 5 [Formula: see text] and residual 69 ± 19 mgCODtot·L(-1)) for more than one year, including over 5 months at 15 °C. The two systems consisted of a moving bed biofilm reactor (MBBR) and a hybrid MBBR (H-MBBR) with flocculent biomass. Operation at limiting oxygen concentrations (0.15-0.18 [Formula: see text] ) allowed stable suppression of the activity of nitrite-oxidizing bacteria at 15 °C with a production of nitrate over ammonium consumed as low as 16% in the MBBR. Promising nitrogen removal rates of 20-40 mgN·L(-1)·d(-1) were maintained at hydraulic retention times of 14 h. Stable ammonium and total nitrogen removal efficiencies over 90% and 70% respectively were achieved. Both reactors reached average concentrations of total nitrogen below 10 mgN·L(-1) in their effluents, even down to 6 mgN·L(-1) for the MBBR, with an ammonium concentration of 2 mgN·L(-1) (set as operational threshold to stop aeration). Furthermore, the two PN/A systems performed almost identically with respect to the biological removal of organic micropollutants and, importantly, to a similar extent as conventional treatments. A sudden temperature drop to 11 °C resulted in significant suppression of anammox activity, although this was rapidly recovered after the temperature was increased back to 15 °C. Analyses of 16S

  13. Occurrence and activity of anammox bacteria in surface sediments of the southern North Sea

    OpenAIRE

    Bale, N.; de Villanueva, L.; Fan, H.; Hopmans, E. C.; Schouten, S.; Sinninghe Damsté, J. S.; Stal, L.J.

    2014-01-01

    We investigated the occurrence and activity of anaerobic ammonia oxidation (anammox) bacteria in sandy and muddy sand sediments of the southern North Sea. The presence of anammox bacteria was established through the detection of specific phosphocholine-monoether ladderane lipids, 16S rRNA gene, and hydrazine synthase (hzsA) genes. Anammox activity was measured in intact sediment cores (in situ rate) and in sediment slurries (potential rate) as the rate of N2 evolution from 15N-labeled substra...

  14. Biophysical properties of membrane lipids of anammox bacteria : I. Ladderane phospholipids form highly organized fluid membranes

    NARCIS (Netherlands)

    Boumann, Henry A.; Longo, Marjorie L.; Stroeve, Pieter; Poolman, Bert; Hopmans, Ellen C.; Stuart, Marc C. A.; Damste, Jaap S. Sinninghe; Schouten, Stefan

    2009-01-01

    Anammox bacteria that are capable of anaerobically oxidizing ammonium (anammox) with nitrite to nitrogen gas produce unique membrane phospholipids that comprise hydrocarbon chains with three or five linearly condensed cyclobutane rings. To gain insight into the biophysical properties of these 'ladde

  15. Long term partial nitritation of anaerobically treated black water and the emission of nitrous oxide.

    Science.gov (United States)

    de Graaff, M S; Zeeman, G; Temmink, H; van Loosdrecht, M C M; Buisman, C J N

    2010-04-01

    Black water (toilet water) contains half the load of organic material and the major fraction of the nutrients nitrogen and phosphorus in a household and is 25 times more concentrated, when collected with a vacuum toilet, than the total wastewater stream from a Dutch household. This research focuses on the partial nitritation of anaerobically treated black water to produce an effluent suitable to feed to the anammox process. Successful partial nitritation was achieved at 34 degrees C and 25 degrees C and for a long period (almost 400 days in the second period at 25 degrees C) without strict process control a stable effluent at a ratio of 1.3 NO(2)-N/NH(4)-N was produced which is suitable to feed to the anammox process. Nitrite oxidizers were successfully outcompeted due to inhibition by free ammonia and nitrous acid and due to fluctuating conditions in SRT (1.0-17 days) and pH (from 6.3 to 7.7) in the reactor. Microbial analysis of the sludge confirmed the presence of mainly ammonium oxidizers. The emission of nitrous oxide (N(2)O) is of growing concern and it corresponded to 0.6-2.6% (average 1.9%) of the total nitrogen load. PMID:20106499

  16. Step-wise temperature decreasing cultivates a biofilm with high nitrogen removal rates at 9°C in short-term anammox biofilm tests.

    Science.gov (United States)

    Zekker, Ivar; Rikmann, Ergo; Mandel, Anni; Kroon, Kristel; Seiman, Andrus; Mihkelson, Jana; Tenno, Taavo; Tenno, Toomas

    2016-08-01

    The anaerobic ammonium oxidation (anammox) and nitritation-anammox (deammonification) processes are widely used for N-rich wastewater treatment. When deammonification applications move towards low temperature applications (mainstream wastewater has low temperature), temperature effect has to be studied. In current research, in a deammonification moving bed biofilm reactor a maximum total nitrogen removal rate (TNRR) of 1.5 g N m(-2 )d(-1) (0.6 kg N m(-3 )d(-1)) was achieved. Temperature was gradually lowered by 0.5°C per week, and a similar TNRR was sustained at 15°C during biofilm cultivation. Statistical analysis confirmed that a temperature decrease from 20°C down to 15° did not cause instabilities. Instead, TNRR rose and treatment efficiency remained stable at lower temperatures as well. Quantitative polymerase chain reaction analyses showed an increase in Candidatus Brocadia quantities from 5 × 10(3) to 1 × 10(7) anammox gene copies g(-1) total suspended solids (TSS) despite temperature lowered to 15°C. Fluctuations in TNRR were rather related to changes in influent [Formula: see text] concentration. To study the short-term effect of temperature on the TNRR, a series of batch-scale experiments were performed which showed sufficient TNRRs even at 9-15°C (1.24-3.43 mg N g(-1 )TSS h(-1), respectively) with anammox temperature constants (Q10) ranging 1.3-1.6. Experiments showed that a biofilm adapted to 15°C can perform N-removal most sufficiently at temperatures down to 9°C as compared with biofilm adapted to higher temperature. After biomass was adapted to 15°C, the decrease in TNRR in batch tests at 9°C was lower (15-20%) than that for biomass adapted to 17-18°C. PMID:26708295

  17. Response of anammox bacteria community structure to nitrogen in paddy soils%稻田厌氧氨氧化菌群落结构对氮肥的响应

    Institute of Scientific and Technical Information of China (English)

    宋亚娜; 吴明基; 林艳

    2013-01-01

    为探明稻田厌氧氨氧化菌多样性及其对氮肥用量的响应状况,利用厌氧氨氧化菌16S rRNA基因特异引物对定位试验稻田土壤DNA进行PCR-DGGE(聚合酶链反应-变性梯度凝胶电泳)并结合DNA克隆测序,研究了氮肥供应量对厌氧氨氧化菌群落结构的影响.DGGE图谱及依据其条带位置和亮度数值计算的多样性指数均显示:高氮处理[N3:225 kg(N)·hm-2]的厌氧氨氧化菌群落结构多样性在表层或根层土壤中均显著(P<0.05)高于中、低氮[N2:150 kg(N)·hm-2; N1:75 kg(N)·hm-2]处理和不施肥对照(CK);同时,高氮处理下表层土壤厌氧氨氧化菌群落多样性指数显著高于根层土壤(P<0.05).冗余分析(RDA)结果表明,表层土壤中厌氧氨氧化菌群落结构组成与不同氮肥水平处理存在显著相关性(P=0.006).此外,本试验获得厌氧氨氧化菌DGGE条带DNA序列18条,登录GenBank并获得登录号.研究表明稻田厌氧氨氧化菌群落结构对高氮水平具有较强的响应,尤其是在表层土壤中.%Anaerobic ammonium oxidizing (anammox) bacteria of phylum Planctomycetes origin have been identified to be responsible for N removal in terrestrial and aquatic environments through combined NFL4+ oxidation and NO2 reduction. Anaerobic ammonium oxidation mediated by anammox bacteria has been noted to be a key process of biogeochemical N cycle in various ecosystems. It was also possible to have anammox processes in flooded paddy fields because of the low oxygen habitat conditions. To investigate the existence of anammox bacteria and the bacteria community diversity response to applied N fertilizer in paddy fields, anammox bacteria community structures in paddy fields were investigated with the aid of denaturing gradient gel electrophoresis and cloning sequencing by assay 16S rRNA gene in the third year of N fertilizer experiment in the field. DGGE images of 16S rRNA gene in surface or root-zone soil showed rich anammox bacteria

  18. Ammonium-oxidizing bacteria facilitate aerobic degradation of sulfanilic acid in activated sludge.

    Science.gov (United States)

    Chen, Gang; Ginige, Maneesha P; Kaksonen, Anna H; Cheng, Ka Yu

    2014-01-01

    Sulfanilic acid (SA) is a toxic sulfonated aromatic amine commonly found in anaerobically treated azo dye contaminated effluents. Aerobic acclimatization of SA-degrading mixed microbial culture could lead to co-enrichment of ammonium-oxidizing bacteria (AOB) because of the concomitant release of ammonium from SA oxidation. To what extent the co-enriched AOB would affect SA oxidation at various ammonium concentrations was unclear. Here, a series of batch kinetic experiments were conducted to evaluate the effect of AOB on aerobic SA degradation in an acclimatized activated sludge culture capable of oxidizing SA and ammonium simultaneously. To account for the effect of AOB on SA degradation, allylthiourea was used to inhibit AOB activity in the culture. The results indicated that specific SA degradation rate of the mixed culture was negatively correlated with the initial ammonium concentration (0-93 mM, R²= 0.99). The presence of AOB accelerated SA degradation by reducing the inhibitory effect of ammonium (≥ 10 mM). The Haldane substrate inhibition model was used to correlate substrate concentration (SA and ammonium) and oxygen uptake rate. This study revealed, for the first time, that AOB could facilitate SA degradation at high concentration of ammonium (≥ 10 mM) in an enriched activated sludge culture. PMID:25259503

  19. Aggregate Size and Architecture Determine Microbial Activity Balance for One-Stage Partial Nitritation and Anammox

    DEFF Research Database (Denmark)

    Vlaeminck, S.E.; Terada, Akihiko; Smets, Barth F.;

    2010-01-01

    Aerobic ammonium-oxidizing bacteria (AerAOB) and anoxic ammonium-oxidizing bacteria (AnAOB) cooperate in partial nitritation/anammox systems to remove ammonium from wastewater. In this process, large granular microbial aggregates enhance the performance, but little is known about granulation so far......AOB abundance and the activity balance for the different aggregate sizes and (ii) to relate aggregate morphology, size distribution, and architecture putatively to the inoculation and operation of the three reactors. A nitrite accumulation rate ratio (NARR) was defined as the net aerobic nitrite production rate...... divided by the anoxic nitrite consumption rate. The smallest reactor A, B, and C aggregates were nitrite sources (NARR, > 1.7). Large reactor A and C aggregates were granules capable of autonomous nitrogen removal (NARR, 0.6 to 1.1) with internal AnAOB zones surrounded by an AerAOB rim. Around 50% of the...

  20. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate

    Science.gov (United States)

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-06-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g‑1 COD and methane percentages of 53–76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L‑1) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg‑1 N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L‑1 d‑1 was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68–95 fmol N cell‑1 d‑1, which finally led to the stable operation of the system.

  1. Niche segregation of ammonia-oxidizing archaea and anammox bacteria in the Arabian Sea oxygen minimum zone

    OpenAIRE

    Pitcher, A.; Villanueva, L; Hopmans, E.C.; Schouten, S.; G. J. Reichart; Sinninghe Damsté, J.S.

    2011-01-01

    Ammonia-oxidizing archaea (AOA) and anaerobic ammonia-oxidizing (anammox) bacteria have emerged as significant factors in the marine nitrogen cycle and are responsible for the oxidation of ammonium to nitrite and dinitrogen gas, respectively. Potential for an interaction between these groups exists; however, their distributions are rarely determined in tandem. Here we have examined the vertical distribution of AOA and anammox bacteria through the Arabian Sea oxygen minimum zone (OMZ), one of ...

  2. Nitrogen removal by granular nitritation-anammox in an upflow membrane-aerated biofilm reactor.

    Science.gov (United States)

    Li, Xiaojin; Sun, Shan; Badgley, Brian D; Sung, Shihwu; Zhang, Husen; He, Zhen

    2016-05-01

    The nitritation-anammox process has been a promising nitrogen removal technology towards sustainable wastewater treatment, but its application in treating domestic wastewater with relatively low ammonium concentrations (mainstream) remains a great challenge. In this study, an innovative lab-scale upflow membrane-aerated biofilm reactor (UMABR) was employed to treat a synthetic wastewater containing 70 mg N L(-1) ammonium. With a DO level at 0.6 ± 0.1 mg O2 L(-1) and HRT of 32 h, the effluent ammonium concentration was 4.8 ± 2.0 mg N L(-1). Increasing the nitrogen loading rate from 52.4 to 104.8 g N m(-3) d(-1) with stepwise decreasing HRT from 32 to 16 h resulted in an average TN removal efficiency of 81% without nitrite accumulation. The average observed NO3(-)-N (residue)/NH4(+)-N (consumed) ratio of 8% was below the "theoretical ratio" of 13% and further reduction of nitrate residue needs to be addressed. Fluorescence in situ hybridization (FISH) and high-throughput sequencing analyses showed the coexistence of anammox bacteria and ammonium-oxidizing bacteria (AOB) in both biofilm and granular samples. Anammox bacteria accounted for up to 63.3% of the microbial community of the granules, with Candidatus Jettenia being the distinctly dominant anammox genus. In contrast, the biofilm contained abundant Nitrosomonadaceae (AOB, 33.1%). In addition, the brown-yellow granules exhibited a more balanced community structure with anammox bacteria and AOB accounting for 33.7% and 18.2%, respectively, which may contribute to the long-term operation of single-stage nitritation-anammox process. These results demonstrate that the nitritation-anammox UMABR could potentially be used for nitrogen removal from mainstream in some specific regions with relatively warm temperature. PMID:26921710

  3. Combined autoradiography and immunofluorescence for estimation of single cell activity by ammonium-oxidizing bacteria

    International Nuclear Information System (INIS)

    Immunofluorescence and 14CO2 autoradiography were used for simultaneously enumerating and assaying the autotrophic activity of ammonium-oxidizing bacteria in seawater. Relative activity (14CO2 assimilation as measured by autoradiography) and abundance were measured in simulated in situ incubations at seven stations in the primary NO2- maximum region of the Northeast Pacific Ocean. More than 104 cells-liter-1 were present; relative activity often showed a peak near the surface and an increase in the NO2- max region below the photic zone. The method permits assessment of individual cell activity; most cells at all depths were active in CO2 assimilation, usually at low and quite variable levels. Relative activity was positively correlated with the abundance of ammonium-oxidizing bacteria, temperature, total dark CO2 assimilation and phenopigment concentration

  4. Performance of Anammox granular sludge bed reactor started up with nitrifying granular sludge

    Institute of Scientific and Technical Information of China (English)

    ZHENG Ping; LIN Feng-mei; HU Bao-lan; CHEN Jian-song

    2004-01-01

    The anaerobic ammonia oxidation(Anammox) granular sludge bed reactor was started up successfully withnitrifying granular sludge. During the operation, the nitrifying granular sludge was gradually converted into Anammoxgranular sludge with good settling property and high conversion activity. The Anammox reactor worked well with theshortest HRT of 2.43 h. Under the condition that HRT was 6.39 h and influent concentration of ammonia and nitritewas 10 mmol/L, the removal of ammonia and nitrite was 97.17% and 100.00%, respectively. Corresponding

  5. Development and optimisation of VFA driven DEAMOX process for treatment of strong nitrogenous anaerobic effluents.

    Science.gov (United States)

    Kalyuzhnyi, S V; Gladchenko, M A; Kang, Ho; Mulder, A; Versprille, A

    2008-01-01

    The recently proposed DEAMOX (DEnitrifying AMmonium OXidation) process combines the anammox reaction with autotrophic denitrifying conditions using sulphide as an electron donor for the production of nitrite from nitrate within an anaerobic biofilm. This paper firstly presents a feasibility study of the DEAMOX process using synthetic (ammonia + nitrate) wastewater where sulphide is replaced by volatile fatty acids (VFA) as a more widespread electron donor for partial denitrification. Under the influent N-NH+4/N-NO3(-) and COD/N-NO3(-) ratios of 1 and 2.3, respectively, the typical efficiencies of ammonia removal were around 40% (no matter whether a VFA mixture or only acetate were used) for nitrogen loading rates (NLR) up to 1236 mg N/l/d. This parameter increased to 80% by increasing the influent COD/N-NO3(-) ratio to 3.48 and decreasing the influent N-NH4 +/N-NO3(-) ratio to 0.29. As a result, the total nitrogen removal increased to 95%. The proposed process was further tested with typical strong nitrogenous effluent such as reject water (total N, 530-566 mg N/l; total COD, 1530-1780 mg/l) after thermophilic sludge anaerobic digestion. For this, the raw wastewater was split and partially ( approximately 50%) fed to a nitrifying reactor (to generate nitrate) and the remaining part ( approximately 50%) was directed to the DEAMOX reactor where this stream was mixed with the nitrified effluent. Stable process performance up to NLR of 1,243 mg N/l/d in the DEAMOX reactor was achieved resulting in 40, 100, and 66% removal of ammonia, NOx(-), and total nitrogen, respectively. PMID:18309208

  6. Nitrogen polishing in a fully anoxic anammox MBBR treating mainstream nitritation-denitritation effluent.

    Science.gov (United States)

    Regmi, Pusker; Holgate, Becky; Miller, Mark W; Park, Hongkeun; Chandran, Kartik; Wett, Bernhard; Murthy, Sudhir; Bott, Charles B

    2016-03-01

    As nitrogen discharge limits are becoming more stringent, short-cut nitrogen systems and tertiary nitrogen polishing steps are gaining popularity. For partial nitritation or nitritation-denitritation systems, anaerobic ammonia oxidation (anammox) polishing may be feasible to remove residual ammonia and nitrite from the effluent. Nitrogen polishing of mainstream nitritation-denitritation system effluent via anammox was studied at 25°C in a fully anoxic moving bed bioreactor (MBBR) (V = 0.45 m(3) ) over 385 days. Unlike other anammox based processes, a very fast startup of anammox MBBR was demonstrated, despite nitrite limited feeding conditions (influent nitrite = 0.7 ± 0.59 mgN/L, ammonia = 6.13 ± 2.86 mgN/L, nitrate = 3.41 ± 1.92 mgN/L). The nitrogen removal performance was very stable within a wide range of nitrogen inputs. Anammox bacteria (AMX) activity up to 1 gN/m(2) /d was observed which is comparable to other biofilm-based systems. It is generally believed that nitrate production limits nitrogen removal through AMX metabolism. However, in this study, anammox MBBR demonstrated ammonia, nitrite, and nitrate removal at limited chemical oxygen demand (COD) availability. AMX and heterotrophs contributed to 0.68 ± 0.17 and 0.32 ± 0.17 of TIN removal, respectively. It was speculated that nitrogen removal might be aided by denitratation which could be due to heterotrophs or the recently discovered ability for AMX to use short-chain fatty acids to reduce nitrate to nitrite. This study demonstrates the feasibility of anammox nitrogen polishing in an MBBR is possible for nitritation-denitration systems. PMID:26333200

  7. Integration of the Anammox process to the rejection water and main stream lines of WWTPs.

    Science.gov (United States)

    Morales, Nicolás; Val Del Río, Ángeles; Vázquez-Padín, José Ramón; Méndez, Ramón; Mosquera-Corral, Anuska; Campos, José Luis

    2015-12-01

    Nowadays the application of Anammox based processes in the wastewater treatment plants has given a step forward. The new goal consists of removing the nitrogen present in the main stream of the WWTPs to improve their energetic efficiencies. This new approach aims to remove not only the nitrogen but also to provide a better use of the energy contained in the organic matter. The organic matter will be removed either by an anaerobic psychrophilic membrane reactor or an aerobic stage operated at low solids retention time followed by an anaerobic digestion of the generated sludge. Then ammonia coming from these units will be removed in an Anammox based process in a single unit system. The second strategy provides the best results in terms of operational costs and would allow reductions of about 28%. Recent research works performed on Anammox based processes and operated at relatively low temperatures and/or low ammonia concentrations were carried out in single-stage systems using biofilms, granules or a mixture of flocculent nitrifying and granular Anammox biomasses. These systems allowed the appropriated retention of Anammox and ammonia oxidizing bacteria but also the proliferation of nitrite oxidizing bacteria which seems to be the main drawback to achieve the required effluent quality for disposal. Therefore, prior to the implementation of the Anammox based processes at full scale to the water line, a reliable strategy to avoid nitrite oxidation should be defined in order to maintain the process stability and to obtain the desired effluent quality. If not, the application of a post-denitrification step should be necessary. PMID:25890586

  8. Distribution and microbial community structure analysis of a single-stage partial nitritation/anammox granular sludge bioreactor operating at low temperature.

    Science.gov (United States)

    Rodriguez-Sanchez, Alejandro; Purswani, Jessica; Lotti, Tommaso; Maza-Marquez, Paula; van Loosdrecht, M C M; Vahala, Riku; Gonzalez-Martinez, Alejandro

    2016-09-01

    In the last decade, autotrophic nitrogen removal technologies based on anammox metabolism have become state of the art in urban and industrial wastewater treatment systems, due to their advantages over traditional nitrogen removal processes. However, their application is currently limited to the treatment of warm wastewater (25-40°C) mainly due to the low growth rate of the anammox bacteria. The extension of the application field to wastewater characterized by lower temperatures (8-20°C), such as those typical for municipal sewage, allows the design of treatment systems with a net energy production. In this study, the distribution and bacterial community structure of a lab-scale single-stage partial nitritation/anammox (PN/A) granular sludge bioreactor operating at low temperatures was analysed using next-generation sequencing techniques. The presence of ammonium-oxidizing bacteria and anammox bacteria was found, but the appearance of other bacterial species shows a complex microbial ecosystem. Evaluation of ecological roles of representative species inside the single-stage PN/A bioreactor was accomplished. Results obtained will be helpful for the future design and operation of PN/A systems performing at low temperatures. PMID:26829222

  9. Combined autoradiography and immunofluorescence for estimation of single cell activity by ammonium-oxidizing bacteria

    International Nuclear Information System (INIS)

    Immunofluorescence and 14CO2 autoradiography were used for simultaneously enumerating and assaying the autotrophic activity of ammonium-oxidizing bacteria in seawater. Relative activity (14CO2 assimilation as measured by autoradiography) and abundance were measured in simulated in situ incubations at seven stations in the primary NO2- maximum region of the Northeast Pacific Ocean. More than 104 cells liter-1 were present; relative activity often showed a peak near the surface and an increase in the NO2- max region below the photic zone. The method permits assessment of individual cell activity; most cells at all depths were active in CO2 assimilation, usually at low and quite variable levels. There were no differences in relative activity between samples incubated under simulated in situ conditions and in the dark. Relative activity was positively correlated with the abundance of ammonium-oxidizing bacteria, temperature, total dark CO2 assimilation (as measured by liquid scintillation counting of replicate samples), and pheopigment concentration, and negatively correlated with oxygen concentration

  10. Niche segregation of ammonia-oxidizing archaea and anammox bacteria in the Arabian Sea oxygen minimum zone

    NARCIS (Netherlands)

    Pitcher, A.; Villanueva, L.; Hopmans, E.C.; Schouten, S.; Reichart, G.J.; Sinninghe Damsté, J.S.

    2011-01-01

    Ammonia-oxidizing archaea (AOA) and anaerobic ammonia-oxidizing (anammox) bacteria have emerged as significant factors in the marine nitrogen cycle and are responsible for the oxidation of ammonium to nitrite and dinitrogen gas, respectively. Potential for an interaction between these groups exists;

  11. Nitrogen removal from sludge dewatering effluent through anaerobic ammonia oxidation process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shao-hui; ZHENG Ping; HUA Yu-mei

    2005-01-01

    Anaerobic ammonia oxidation(Anammox) process is a novel and promising wastewater nitrogen removal process. The feasibility of transition of Anammox from denitrification and the performance of lab-scale Anammox biofilm reactor were investigated with sludge dewatering effluent. The results showed that Anammox process could be successfully started up after cultivation of denitrification biofilm and using it as inoculum. The transition of Anammox from denitrification was accomplished within 85 d. Anammox process was found suitable to remove ammonia from sludge dewatering effluent. The effluent ammonia concentration was detected to be 23.11 mgN/L at HRT of 28 h when influent ammonia concentration was fed 245 mgN/L, which was less than that for the national discharge standard Ⅱ (25 mgN/L) of 243.25 mg NH4+ -N/L and 288.31 mg NO2- -N/L.

  12. Nitrogen loss by anaerobic oxidation of ammonium in rice rhizosphere

    OpenAIRE

    Nie, San'an; Li, Hu; Yang, Xiaoru; Zhang, Zhaoji; Weng, Bosen; Huang, Fuyi; Zhu, Gui-Bing; Zhu, Yong-Guan

    2015-01-01

    Anaerobic oxidation of ammonium (anammox) is recognized as an important process for nitrogen (N) cycling, yet its role in agricultural ecosystems, which are intensively fertilized, remains unclear. In this study, we investigated the presence, activity, functional gene abundance and role of anammox bacteria in rhizosphere and non-rhizosphere paddy soils using catalyzed reporter deposition–fluorescence in situ hybridization, isotope-tracing technique, quantitative PCR assay and 16S rRNA gene cl...

  13. The Short-term Effects of Temperature and Free Ammonia on Ammonium Oxidization in Granular and Floccular Nitrifying System

    Institute of Scientific and Technical Information of China (English)

    吴蕾; 彭永臻; 马勇; 刘旭; 李凌云; 王淑莹

    2012-01-01

    The short-term effects of temperature and free ammonia (FA) on ammonium oxidization were investigated in this study by operating several batch tests with two different partial nitrification aggregates, formed as either granules or flocs. The results showed that the rate of ammonium oxidation in both cultures increased significantly as temperature increased from 10 to 30 °C. The specific ammonium oxidation rate with the granules was 2-3 times higher than that with flocs at the same temperature. Nitrification at various FA concentrations and temperatures combination exhibited obvious inhibition in ammonium oxidation rate when FA was 90 mg·L 1 and tempera- ture dropped to 10 °C in the two systems. However, the increase in substrate oxidation rate of ammonia at 30 °C was observed. The results suggested that higher reaction temperature was helpful to reduce the toxicity of FA. Granules appeared to be more tolerant to FA attributed to the much fraction of ammonia oxidizing bacteria (AOB) and higher resistance to the transfer of ammonia into the bacterial aggregates, whereas in the floc system, the bacteria distributed throughout the entire aggregate. These results may contribute to the applicability of the nitrifying granules in wastewater treatment operated at high ammonium concentration.

  14. Production and mitigation of N2O in sequentially membrane-aerated redox-stratified nitritation/anammox biofilms

    DEFF Research Database (Denmark)

    Smets, Barth F.; Pellicer i Nàcher, Carles; Thamdrup, Bo;

    Combining partial nitritation with anaerobic ammonium oxidation maybe a cost- and energy-efficient alternative to remove reduced nitrogen from nitrogen rich waste streams. However, increased N2O emissions (upto several % of the incoming N flux) have been observed for reactors performing partial...... nitritation, which is likely due to the stimulatory effect of combined elevated nitrite and ammonium concentrations and reduced oxygen concentrations on nitrous oxide formation by ammonium oxidizing bacteria. Because increased N2O emission may be inherent to partial nitrification systems, we have explored how...... converted ammonium N. Anoxic batch incubations with biofilm samples revealed a significant N2O assimilatory activity. Anoxic incubations with N-15 enriched nitrite, nitrate, or ammonium, in presence or absence of acetate revealed the following: a very high conversion of original nitrite or nitrate N to N2O...

  15. Analysis of the impact of reflux ratio on coupled partial nitrification-anammox for co-treatment of mature landfill leachate and domestic wastewater.

    Science.gov (United States)

    Wu, Lina; Zhang, Lieyu; Shi, Xiao; Liu, Ting; Peng, Yongzhen; Zhang, Jie

    2015-12-01

    A combined system of anaerobic-aerobic techniques was used for deep co-treatment of mature landfill leachate and domestic sewage, mixed at a ratio of 1:5, through partial nitrification-anammox. While ensuring synchronous removal of organic matter and nitrogen, we investigated changes in several factors under different reflux ratios (0%, 100% and 300%). High nitrification efficiency and a relatively high accumulation rate of NO2(-)-N were achieved, the latter through selective inhibition of bacteria by free ammonia. The results indicated that maintaining the reflux ratio within an optimum range contributes to the enrichment of anammox bacteria. In this study, the optimum ratio, which permitted the highest removal rates of chemical oxygen demand (COD), NH4(+)-N, and total nitrogen, was 300%. The COD level in the anammox reactor (ANAOR) decreased to lower than 70 mg/L, resulting in no inhibitory effect on anammox and maximum enrichment of bacteria. PMID:26386424

  16. Metagenome analysis of a complex community reveals the metabolic blueprint of anammox bacterium ‘Candidatus Jettenia asiatica’

    Directory of Open Access Journals (Sweden)

    ZiyeHu

    2012-10-01

    Full Text Available Anammox bacteria are key players in the global nitrogen cycle and responsible for up to 50% of global nitrogen loss. Because of their cost effective application in anaerobic nitrogen removal, the anammox bacteria are widely implemented in wastewater treatment. Currently, five genera of anammox bacteria have been identified, together forming a deep branching order in the Planctomycetes-Verrucomicrobium- Chlamydiae (PVC superphylum. Members of all genera have been detected in wastewater treatment plants, but metagenomic information is not yet available for all genera. Here we report the metagenomic analysis of an enrichment dominated by ‘Candidatus Jettenia asiatica’. The whole microbial community o\tf a granular sludge anammox reactor was sequenced using both illumina and 454 pyrosequencing. The sludge was previously shown to have a ~50% enrichment of the anammox bacterium ‘Candidatus Jettenia asiatica’ by 16S rRNA gene analysis. After de novo assembly 37,432 contigs with an average length of 571 nt were obtained. The contigs were then analyzed by BLASTx searches against the protein sequences of ‘Candidatus Kuenenia stuttgartiensis’ and a set of 25 genes essential in anammox metabolism were detected. Additionally all reads were mapped to the genome of an anammox strain KSU-1 and de novo assembly was performed again using the reads that could be mapped on KSU-1. Using this approach, a gene encoding copper-containing nitrite reductase NirK was identified in the genome, instead of cytochrome cd1-type nitrite reductase NirS that is responsible for the nitrite reduction of ‘Ca. Kuenenia stuttgartiensis’ and ‘Ca. Scalindua profunda’. Finally, the community composition was investigated through MetaCluster analysis, 16S rRNA gene analysis and read mapping, which showed the presence of other important community members such as aerobic ammonia-oxidizing bacteria, methane producing microorganisms and denitrifying methanotroph 'Ca

  17. Oxygen sensitivity of anammox and coupled N-cycle processes in oxygen minimum zones.

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    Tim Kalvelage

    Full Text Available Nutrient measurements indicate that 30-50% of the total nitrogen (N loss in the ocean occurs in oxygen minimum zones (OMZs. This pelagic N-removal takes place within only ~0.1% of the ocean volume, hence moderate variations in the extent of OMZs due to global warming may have a large impact on the global N-cycle. We examined the effect of oxygen (O(2 on anammox, NH(3 oxidation and NO(3(- reduction in (15N-labeling experiments with varying O(2 concentrations (0-25 µmol L(-1 in the Namibian and Peruvian OMZs. Our results show that O(2 is a major controlling factor for anammox activity in OMZ waters. Based on our O(2 assays we estimate the upper limit for anammox to be ~20 µmol L(-1. In contrast, NH(3 oxidation to NO(2(- and NO(3(- reduction to NO(2(- as the main NH(4(+ and NO(2(- sources for anammox were only moderately affected by changing O(2 concentrations. Intriguingly, aerobic NH(3 oxidation was active at non-detectable concentrations of O(2, while anaerobic NO(3(- reduction was fully active up to at least 25 µmol L(-1 O(2. Hence, aerobic and anaerobic N-cycle pathways in OMZs can co-occur over a larger range of O(2 concentrations than previously assumed. The zone where N-loss can occur is primarily controlled by the O(2-sensitivity of anammox itself, and not by any effects of O(2 on the tightly coupled pathways of aerobic NH(3 oxidation and NO(3(- reduction. With anammox bacteria in the marine environment being active at O(2 levels ~20 times higher than those known to inhibit their cultured counterparts, the oceanic volume potentially acting as a N-sink increases tenfold. The predicted expansion of OMZs may enlarge this volume even further. Our study provides the first robust estimates of O(2 sensitivities for processes directly and indirectly connected with N-loss. These are essential to assess the effects of ocean de-oxygenation on oceanic N-cycling.

  18. Amplification of the amoA gene from diverse species of ammonium-oxidizing bacteria and from an indigenous bacterial population from seawater.

    OpenAIRE

    Sinigalliano, C.D.; Kuhn, D N; Jones, R D

    1995-01-01

    Because the chemolithotrophic ammonium-oxidizing bacteria are an integral component of nitrogen biogeochemistry, a sensitive and accurate method to detect this ecologically important group of microorganisms is needed. The amoA gene of these organisms encodes the active site of ammonia monooxygenase, an enzyme unique to this group of nitrifying bacteria. We report here the use of the PCR technique to detect the amoA gene from pure cultures of chemolithotrophic ammonium-oxidizing bacteria, ammo...

  19. Microcalorimetric and manometric tests to assess anammox activity.

    Science.gov (United States)

    Scaglione, D; Buttiglieri, G; Ficara, E; Caffaz, S; Lubello, C; Malpei, F

    2009-01-01

    The present study compares two experimental methods to evaluate Anammox activity based on the assessment of (1) the N(2) production rate by a manometric device, as previously proposed, and (2) the heat production rate by a microcalorimeter. Two samples of Anammox suspended biomass were taken from a pilot-plant, and their specific Anammox activity measured by both techniques. Both methods were successfully applied. As for calorimetric tests, they were performed for the first time on Anammox enriched sludge samples. Comparisons between the specific Anammox activities estimated by manometry and calorimetry and between expected (from the reaction enthalpy) and measured heat productions were performed. Promising results were obtained. PMID:19923777

  20. Discovery of anammox bacteria in terrestrial ecosystems

    OpenAIRE

    Humbert, Sylvia; Aragno, Michel; Zopfi, Jakob

    2011-01-01

    Avant cette étude, le processus anammox (oxydation anaérobie de l’ammonium) était uniquement étudié dans les usines de traitement des eaux usées et dans les milieux aquatiques, sédiments inclus. Cependant, rien n'était connu encore sur la distribution, la diversité, l'abondance et l'activité des bactéries anammox dans les écosystèmes terrestres. Dans cette étude, nous apportons l’évidence, par approche moléculaire, de la présence de bactéries anammox dans les sols de zones humides, les sédime...

  1. Evaluating primers for profiling anaerobic ammonia oxidizing bacteria within freshwater environments.

    Directory of Open Access Journals (Sweden)

    Puntipar Sonthiphand

    Full Text Available Anaerobic ammonia oxidizing (anammox bacteria play an important role in transforming ammonium to nitrogen gas and contribute to fixed nitrogen losses in freshwater environments. Understanding the diversity and abundance of anammox bacteria requires reliable molecular tools, and these are not yet well established for these important Planctomycetes. To help validate PCR primers for the detection of anammox bacteria within freshwater ecosystems, we analyzed representative positive controls and selected samples from Grand River and groundwater sites, both from Ontario, Canada. The objectives of this study were to identify a suitable anammox denaturing gradient gel electrophoresis (DGGE fingerprint method by using GC-clamp modifications to existing primers, and to verify the specificity of anammox-specific primers used for DGGE, cloning and qPCR methods. Six primer combinations were tested from four published primer sets (i.e. A438f/A684r, Amx368f/Amx820r, An7f/An1388r, and Pla46/1392r for both direct and nested PCR amplifications. All PCR products were run subsequently on DGGE gels to compare the resulting patterns. Two anammox-specific primer combinations were also used to generate clone libraries and quantify anammox bacterial 16S rRNA genes with qPCR. The primer set A438f/A684r was highly specific to anammox bacteria, provided reliable DGGE fingerprints and generated a high proportion of anammox-related clones. A second primer set (Amx368f/Amx820r was anammox specific, based on clone library analysis, but PCR products from different candidate species of anammox bacteria resolved poorly using DGGE analysis. Both DGGE and cloning results revealed that Ca. Brocadia and an uncharacterized anammox bacterial cluster represented the majority of anammox bacteria found in Grand River sediment and groundwater samples, respectively. Together, our results demonstrate that although Amx368f/Amx820r was useful for anammox-specific qPCR and clone library

  2. Suspended sludge and biofilm shaped different anammox communities in two pilot-scale one-stage anammox reactors.

    Science.gov (United States)

    Zheng, Bingyu; Zhang, Liang; Guo, Jianhua; Zhang, Shujun; Yang, Anming; Peng, Yongzhen

    2016-07-01

    The abundance and diversity of anammox bacteria was investigated in two pilot-scale integrated fixed-film activated sludge (IFAS) reactors treating high ammonium wastewater. Reactor A was inoculated with nitrifying sludge, while Reactor B was inoculated with suspended anammox sludge with the dominant anammox bacteria of Candidatus 'Kuenenia'. After 180days' operation, the predominate anammox bacteria was Candidatus 'Brocadia' (65%) in the biofilm, while Candidatus 'Kuenenia' (86%) outcompeted with other anammox bacteria in suspended sludge in Reactor A. Candidatus 'Kuenenia' were dominated in suspended sludge through the entire experiment in Reactor B. In contrast, the predominated species shifted from Candidatus 'Kuenenia' (89%) into Candidatus 'Brocadia' (66%) in the biofilm of Reactor B. This study indicated that Candidatus 'Brocadia' preferred to grow in the biofilm, while Candidatus 'Kuenenia' would dominant over other anammox bacteria in the suspended sludge. Further studies are required to identify the internal factors affecting the distribution of anammox bacteria. PMID:27023382

  3. Nitrogen removal properties in a continuous marine anammox bacteria reactor under rapid and extensive salinity changes.

    Science.gov (United States)

    Wei, Qiaoyan; Kawagoshi, Yasunori; Huang, Xiaowu; Hong, Nian; Van Duc, Luong; Yamashita, Yuki; Hama, Takehide

    2016-04-01

    Salinity tolerance is one of the most important factors for the application of bioreactors to high-salinity wastewater. Although marine anammox bacteria (MAB) might be expected to tolerate higher salinities than freshwater anammox bacteria, there is little information on the effects of salinity on MAB activity. This study aimed to reveal the nitrogen removal properties in a continuous MAB reactor under conditions of rapid and extensive salinity changes. The reactor demonstrated stable nitrogen removal performance with a removal efficiency of over 85% under salinity conditions ranging from 0 to 50 g/L NaCl. The reactor performance was also well maintained, even though the salinity was rapidly changed from 30 to 50 g/L and from 30 to 0 g/L. Other evidence suggested that the seawater medium used contained components essential for effective MAB performance. Bacterial community analysis using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) showed that planctomycete UKU-1, the dominant MAB species in the inoculum, was the main contributor to anammox activity under all conditions. The PCR-DGGE using a universal bacterial primer set showed different DNA band patterns between the reactor biomass sample collected under conditions of 75 g/L NaCl and all other conditions (0, 30, 50 and freshwater-medium). All DNA sequences determined were very similar to those of bacterial species from marine environments, anaerobic environments, or wastewater-treatment facilities. PMID:26845464

  4. Isolation and identification of bacteria responsible for simultaneous anaerobic ammonium and sulfate removal

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Sulfate-dependent anaerobic ammonium oxidation is a novel biological reaction,in which ammonium is oxidized with sulfate as the electron acceptor under anoxic conditions.Ammonium and sulfate are cosmopolitan chemical species which are an integral part of the global nitrogen and sulfur cycles.A detailed exploration of sulfate-dependent anaerobic ammonium oxidation is quite practical.In this work,a bacterial strain named ASR has been isolated from an anaerobic ammonia and sulfate removing reactor working under steady-state.On the basis of electron microscopy,physiological tests and 16S rDNA phylogenetic sequence analysis,the strain ASR is found to be related to Bacillus benzoevorans.According to the biological carbon source utilization test,the strain ASR could use many carbon sources.Its optimum pH value and temperature were 8.5 and 30 °C,respectively.The test proves that the strain ASR is able to use sulfate to oxidize ammonia anaerobically.The maximum ammonia and sulfate removal rates were 44.4% and 40.0%,respectively.The present study provided biological evidence for the confirmation and development of sulfate-dependent anaerobic ammonium oxidation and brought new insights into the global nitrogen and sulfur cycles.

  5. Effects of polybrominated diphenyl ethers and plant species on nitrification, denitrification and anammox in mangrove soils.

    Science.gov (United States)

    Chen, Juan; Zhou, Hai Chao; Pan, Ying; Shyla, Farzana Shazia; Tam, Nora Fung-Yee

    2016-05-15

    Little is known about polybrominated diphenyl ethers (PBDEs) and planting affect biogeochemical processes, and their impact on microbial nitrogen (N) transformation in soil. A 12-month microcosm experiment was conducted to understand the effects of a mixture of PBDEs at two contamination levels, 2 and 20 mg kg(-1)dry weight representing low and high soil contamination, respectively, using two mangrove plant species, namely Kandelia obovata (Ko) and Bruguiera gymnorrhiza (Bg), on nitrification, denitrification and anammox in mangrove soils. No significant changes in these N transformation processes were found at month 3 and at a low level of PBDEs in both plant species, suggesting that short-term exposure to 2 mg kg(-1) contamination did not affect microbial N transformation. At month 12, a high level of PBDE contamination significantly decreased the nitrification potential activity and the copy numbers of archaeal amoA and bacterial amoA gene in Ko soil, but such inhibitory effect was not significant in Bg soil. On the contrary, the denitrification-related parameters, including the activities of nitrate reductase and nitrite reductase, potential denitrification activity and copy numbers of nirK, nirS and nosZ gene, were stimulated by a high level of PBDE contamination in both Ko and Bg soils, and the stimulation was higher in the more anaerobic Bg soil. Different from denitrification, a high level of PBDE contamination decreased the copy numbers of anammox bacterial 16S rRNA gene in Bg soil but not in Ko soil; this was possibly related to the lower nitrate concentration in Bg soil that might inhibit the growth of anammox bacteria. These results indicated that the effects of PBDEs on microbial N transformation were plant species-specific, with the nitrifying microorganisms in Ko soil more susceptible to PBDE contamination, while denitrification and anammox in Bg soil were more sensitive. PMID:26901803

  6. [Effect of High Ammonium on Nitrogen Removal in an Partial Nitritation-ANAMMOX Process with Reflux System].

    Science.gov (United States)

    Li, Xiang; Cui, Jian-hong; Yuan, Yan; Huang, Yong; Yuan, Yi; Liu, Xin

    2015-10-01

    The effect of influent ammonia on nitrogen transformation characteristics and microbial communities in partial nitrification-anaerobic ammonia oxidation (PN-ANAMMOX) process was studied by using a series of partial nitrification and ANAMMOX process with air-lift reflux device. The results showed that when the influent ammonia concentration was increased to 700 mg x L(-1) and the nitrogen volume load was stabled at 2.8 kg x (m3 x d)(-1), the fluctuation of pH value was very small in aerobic and anaerobic zone. In the aerobic and anaerobic zone, FA concentrations were maintained at 5'mg x L(-1), 10 mg x L(-1), respectively, which did not inhibit the growth of microorganisms. Nitrite produce rate was stabled at 1.5 kg x (m3 x d)(-1) in the aerobic zone, and nitrogen removal rate was stabled at 31.49 kg x (m3 x d)(-1) in anaerobic zone, the total nitrogen removal rate was stabled at 1.67 kg x (m3 x d)(-1) in combined process. When the influent ammonia concentration was increased to 900 mg x L(-1), the FA and FNA concentration were increased in each areas, total nitrogen removal rate was decreased and stabled at 1.52 kg x- ( m3x- d( 1)'. The nitrite was accumulated in the anaerobic zone, and there was no significant inhibition of ANAMMOX bacteria. Our findings indicated that the reflux can effectively alleviate the fluctuation of pH in each area, and dilute FA concentration which is toxic to microorganisms. PMID:26841608

  7. Ammonium Oxidation Under Iron Reducing Conditions: Environmental Factors Characterization and Process Optimization

    Science.gov (United States)

    Huang, Shan; Ruiz, Melany; Jaffe, Peter

    2015-04-01

    Ammonium (NH4+) oxidation coupled to iron (Fe) reduction in the absence of oxygen and nitrate/nitrite (NO3-/NO2-) has been reported by several investigators and is referred to as Feammox. Feammox is a biological reaction, where Fe(III) is the electron acceptor, which is reduced to Fe(II), and NH4+ is the electron donor, which is oxidized to NO2-. An Acidimicrobiaceae bacterium named A6, a previously unreported species in the Acidimicrobiaceae family, has been identified as being responsible for the Feammox process(1, 2) Feammox process was noted in riparian wetland soils in New Jersey(1,3), in tropical rainforest soils in Puerto Rico (4) and in paddy soils in China (5). In addition to these published locations, Feammox process was also found in samples collected from a series of local wetland-, upland-, as well as storm-water detention pond-sediments in New Jersey, river sediments from South Carolina, and forested soils near an acid mine drainage (Dabaoshan, Guangdong province) in China. Using primers acm342f - 439r (2), Acidimicrobiaceae bacterium A6 was detected in samples where Feammox was observed, after strictly anaerobic incubations. According to a canonical correspondence analysis with environmental characteristics and soil microbial communities, the species-environment relationship indicated that pH and Fe oxides content were the primary factors controlling Feammox process. Anaerobic incubations of Feammox enrichment cultures adjusted to different pH, revealed that the optimal pH for Feammox is 4 ~ 5, and the reaction does not proceed when pH > 7. No correlation was found between the distributions of Feammox bacteria and other NH4+ oxidation bacteria. Pure Acidimicrobiaceae bacterium A6 strain was isolated in an autotrophic medium, from an active Feammox membrane reactor (A6 was enriched to 65.8% of the total bacteria). A 13C labeled CO2 amendment was conducted, and the 13C in cells of A6 increased from 1.80% to 10.3% after 14 days incubation. In a separate

  8. Temperature response of denitrification and anammox reveals the adaptation of microbial communities to in situ temperatures in permeable marine sediments that span 50° in latitude

    Directory of Open Access Journals (Sweden)

    A. Canion

    2013-09-01

    Full Text Available Despite decades of research on the physiology and biochemistry of nitrate/nitrite-respiring microorganisms, little is known regarding their metabolic response to temperature, especially under in situ conditions. The temperature regulation of microbial communities that mediate anammox and denitrification was investigated in near shore permeable sediments at polar, temperate, and subtropical sites with annual mean temperatures ranging from −5 to 23 °C. Total N2 production rates were determined using the isotope pairing technique in intact core incubations under diffusive and simulated advection conditions and ranged from 2 to 359 μmol N m−2 d−1. For the majority of sites studied, N2 removal was 2 to 7 times more rapid under advective flow conditions. Anammox comprised 6 to 14% of total N2 production at temperate and polar sites and was not detected at the subtropical site. Potential rates of denitrification and anammox were determined in anaerobic slurries in a temperature gradient block incubator across a temperature range of −1 to 42 °C. The highest optimum temperature (Topt for denitrification was 36 °C and was observed in subtropical sediments, while the lowest Topt of 21 °C was observed at the polar site. Seasonal variation in the Topt was observed at the temperate site with values of 26 and 34 °C in winter and summer, respectively. The Topt values for anammox were 9 and 26 °C at the polar and temperate sites, respectively. The results demonstrate adaptation of denitrifying communities to in situ temperatures in permeable marine sediments across a wide range of temperatures, whereas marine anammox bacteria may be predominately psychrophilic to psychrotolerant. To our knowledge, we provide the first rates of denitrification and anammox from permeable sediments of a polar permanently cold ecosystem. The adaptation of microbial communities to in situ temperatures suggests that the relationship between temperature and rates of N

  9. [Detection of anaerobic processes and microorganisms in immobilized activated sludge of a wastewater treatment plant with intense aeration].

    Science.gov (United States)

    Litti, Iu V; Nekrasova, V K; Kulikov, N I; Siman'kova, M V; Nozhevnikova, A N

    2013-01-01

    Attached activated sludge from the Krasnaya Polyana (Sochi) wastewater treatment plant was studied after the reconstruction by increased aeration and water recycle, as well as by the installation of a bristle carrier for activated sludge immobilization. The activated sludge biofilms developing under conditions of intense aeration were shown to contain both aerobic and anaerobic microorganisms. Activity of a strictly anaerobic methanogenic community was revealed, which degraded organic compounds to methane, further oxidized by aerobic methanotrophs. Volatile fatty acids, the intermediates of anaerobic degradation of complex organic compounds, were used by both aerobic and anaerobic microorganisms. Anaerobic oxidation of ammonium with nitrite (anammox) and the presence of obligate anammox bacteria were revealed in attached activated sludge biofilms. Simultaneous aerobic and anaerobic degradation of organic contaminants by attached activated sludge provides for high rates of water treatment, stability of the activated sludge under variable environmental conditions, and decreased excess sludge formation. PMID:25509405

  10. Anaerobes beyond anaerobic digestion

    OpenAIRE

    Sousa, D. Z.; Pereira, M A; Alves, M.M.

    2009-01-01

    Anaerobic microorganisms are widespread in nature. Sediments, gastrointestinal tracks, volcanic vents, geothermal sources are examples of habitats where anaerobic metabolism prevail, in some cases at extreme temperature, pH and pressure conditions. In such microbial ecosystems waste of some is food for others in a true integrated structure. Anaerobic microorganisms are able to use a wide variety of organic and inorganic compounds. Recalcitrant compounds, such as hydrocarbons, a...

  11. Monitoring the nitrification and identifying the endpoint of ammonium oxidation by using a novel system of titrimetry.

    Science.gov (United States)

    Zhang, Xin; Zhang, Daijun; Lu, Peili; Bai, Cui; Xiao, Pengying

    2011-01-01

    Based on the structure of the hybrid respirometer previously developed in our group, a novel implementation for titrimetry was developed, in which two pH electrodes were installed at the inlet and outlet of the measuring cell. The software capable of digital filtering and titration time delay correction was developed in LabVIEW. The hardware and software of the titrimeter and the respirometer were integrated to construct a novel system of respirometry-titrimetry. The system was applied to monitor a batch nitrification process. The obtained profiles of oxygen uptake rate (OUR) and hydrogen ion production rate (HPR) are consistent with each other and agree with the principle of the biological nitrification reaction. According to the OUR and HPR measurements, the oxidized ammonium concentrations were estimated accurately. Furthermore, the endpoint of ammonium oxidation was identified with much higher sensitivity by the HPR measurement. The system could be potentially used for on-line monitoring of biochemical reactions occurring in any kind of bioreactors because its measuring cell is completely independent of the bioreactor. PMID:22156129

  12. Intact polar lipids of Thaumarchaeota and anammox bacteria as indicators of N cycling in the eastern tropical North Pacific oxygen-deficient zone

    Science.gov (United States)

    Sollai, M.; Hopmans, E. C.; Schouten, S.; Keil, R. G.; Sinninghe Damsté, J. S.

    2015-08-01

    In the last decade our understanding of the marine nitrogen cycle has improved considerably thanks to the discovery of two novel groups of microorganisms: ammonia-oxidizing archaea (AOA) and anaerobic ammonia-oxidizing (anammox) bacteria. Both groups are important in oxygen-deficient zones (ODZs), where they substantially affect the marine N budget. These two groups of microbes are also well known for producing specific membrane lipids, which can be used as biomarkers to trace their presence in the environment. We investigated the occurrence and distribution of AOA and anammox bacteria in the water column of the eastern tropical North Pacific (ETNP) ODZ, one of the most prominent ODZs worldwide. Suspended particulate matter (SPM) was collected at different depths of the water column in high resolution, at both a coastal and an open-ocean setting. The SPM was analyzed for AOA- and anammox bacteria-specific intact polar lipids (IPLs), i.e., hexose-phosphohexose (HPH)-crenarchaeol and phosphatidylcholine (PC)-monoether ladderane. Comparison with oxygen profiles reveals that both the microbial groups are able to thrive at low (niche segregation of AOA and anammox bacteria in the coastal waters of the ETNP but a partial overlap of the two niches of these microbial species in the open-water setting. The latter distribution suggests the potential for an interaction between the two microbial groups at the open-ocean site, although the nature of this hypothetical interaction (i.e., either competition or cooperation) remains unclear.

  13. Intact polar lipids of Thaumarchaeota and anammox bacteria as indicators of N-cycling in the Eastern Tropical North Pacific oxygen deficient zone

    Science.gov (United States)

    Sollai, M.; Hopmans, E. C.; Schouten, S.; Keil, R. G.; Sinninghe Damsté, J. S.

    2015-03-01

    In the last decade our understanding of the marine nitrogen cycle has improved considerably thanks to the discovery of two novel groups of microorganisms: ammonia-oxidizing archaea (AOA) and anaerobic ammonia-oxidizing (anammox) bacteria. Both groups are important in oxygen deficient zones (ODZs), where they substantially affect the marine N-budget. These two groups of microbes are also well known for producing specific membrane lipids, which can be used as biomarkers to trace their presence in the environment. We investigated the occurrence and distribution of AOA and anammox bacteria in the water column of the Eastern Tropical North Pacific (ETNP) ODZ, one of the most prominent ODZs worldwide. Suspended particulate matter (SPM) was collected at different depths of the water column in high resolution, at both a coastal and an open ocean setting. The SPM was analyzed for AOA- and anammox bacteria-specific intact polar lipids (IPLs), i.e. hexose-phosphohexose (HPH)-crenarchaeol and phosphatidylcholine (PC)-monoether ladderane. Comparison with oxygen profiles reveals that both the microbial groups are able to thrive at low (niche segregation of AOA and anammox bacteria in the coastal waters of the ETNP, but a partial overlap of the two niches of these microbial species in the open water setting. The latter distribution suggests the potential for an interaction between the two microbial groups at the open ocean site, either as competition or cooperation.

  14. Intact polar lipids of Thaumarchaeota and anammox bacteria as indicators of N-cycling in the Eastern Tropical North Pacific oxygen deficient zone

    Directory of Open Access Journals (Sweden)

    M. Sollai

    2015-03-01

    Full Text Available In the last decade our understanding of the marine nitrogen cycle has improved considerably thanks to the discovery of two novel groups of microorganisms: ammonia-oxidizing archaea (AOA and anaerobic ammonia-oxidizing (anammox bacteria. Both groups are important in oxygen deficient zones (ODZs, where they substantially affect the marine N-budget. These two groups of microbes are also well known for producing specific membrane lipids, which can be used as biomarkers to trace their presence in the environment. We investigated the occurrence and distribution of AOA and anammox bacteria in the water column of the Eastern Tropical North Pacific (ETNP ODZ, one of the most prominent ODZs worldwide. Suspended particulate matter (SPM was collected at different depths of the water column in high resolution, at both a coastal and an open ocean setting. The SPM was analyzed for AOA- and anammox bacteria-specific intact polar lipids (IPLs, i.e. hexose-phosphohexose (HPH-crenarchaeol and phosphatidylcholine (PC-monoether ladderane. Comparison with oxygen profiles reveals that both the microbial groups are able to thrive at low (<1 μM concentrations of oxygen. Our results indicate a clear niche segregation of AOA and anammox bacteria in the coastal waters of the ETNP, but a partial overlap of the two niches of these microbial species in the open water setting. The latter distribution suggests the potential for an interaction between the two microbial groups at the open ocean site, either as competition or cooperation.

  15. NOx and ammonium isotopic fingerprints of anammox in natural and engineered systems: Implications for N isotope budgets and the use of NOx isotopes to diagnose process stability in wastewater treatment

    Science.gov (United States)

    Lehmann, M. F.; Stöcklin, N.; Brunner, B.; Frame, C. H.; Joss, A.; Kipf, M.; Kuhn, T.; Wunderlin, P.

    2014-12-01

    The anaerobic oxidation of ammonium with nitrite (anammox) has been identified as a very important fixed nitrogen (N) sink, accounting for a large fraction of global fixed N loss in marine, freshwater, and semi-terrestrial environments. In engineered systems, combined nitritation-anammox is an efficient process to remove N from ammonium-rich wastewater, with nitrite as the central intermediate. During the anammox process, nitrate is being produced, providing reducing equivalents for carbon fixation. Measuring the N isotope ratios in fixed N species (i.e., ammonium, nitrite, nitrate) has proven to be a valuable tool to track N cycling in freshwater and marine ecosystems, yet its application in wastewater treatment as a tool to diagnose nitrate production pathways is novel. In this presentation we will elucidate, and compare, the N isotope effects associated with anammox 1) in vitro, 2) in a lacustrine setting, and 3) in a small-scale batch reactor for wastewater treatment. We demonstrate that the anammox nitrite/nitrate isotopic signatures are modulated by the superposition of strong kinetic (normal and inverse) and equilibrium (nitrite-nitrate) N isotope fractionation. The ammonium N isotope effect is driven by kinetic N isotope fractionation, and is similar to that of nitrification. We will discuss the possible controls on the expression of the anammox N isotope effects in the natural environment. We will also evaluate the use of nitrate/nitrite N (and O) isotope signatures to distinguish between nitrate production by anammox versus nitrite oxidation, which is important for optimizing process efficiency during wastewater treatment.

  16. Combination of complex adsorption and anammox for nitric oxide removal.

    Science.gov (United States)

    Wang, Xiaojing; Xu, Xiaochen; Liu, Sitong; Zhang, Yun; Zhao, Chuanqi; Yang, Fenglin

    2016-07-15

    High-efficiency Fe(II)EDTA (approximately 80%) was selected to remove nitric oxide (NO) in a complex adsorption process; subsequently, this Fe(II)EDTA was combined with the anammox process to eliminate the NO in flue gas. The Fe(II)EDTA-NO solution negatively affected the conventional nitrite-dependent anammox bacteria when the solution concentration exceeded 0.5mM. Fe(II)EDTA-NO-cultivated anammox bacteria removed the ammonium coupled to complex NO reduction (≤3.5mM). The batch test results demonstrated that NH4(+) was eliminated through Fe(II)EDTA-NO reduction via anammox. The removal of complex NO and NH4(+) exhibited high relativity relevance, and the Fe(II)EDTA-NO/NH4(+) molar ratio was approximately 0.97. The complex NO-dependent process generates lesser nitrate than that generated by conventional anammox. Moreover, Candidatus Kuenenia stuttgartiensitiensis became the dominant anammox bacterial community when the biomass is cultivated using the inoculated bacteria, and the proportion of the former increased to 90% from the initial 38% for ribosomal intergenic spacer analysis and library construction. PMID:27037471

  17. Temperature response of denitrification and anammox reveals the adaptation of microbial communities to in situ temperatures in permeable marine sediments that span 50° in latitude

    Science.gov (United States)

    Canion, A.; Kostka, J. E.; Gihring, T. M.; Huettel, M.; van Beusekom, J. E. E.; Gao, H.; Lavik, G.; Kuypers, M. M. M.

    2014-01-01

    Despite decades of research on the physiology and biochemistry of nitrate/nitrite-respiring microorganisms, little is known regarding their metabolic response to temperature, especially under in situ conditions. The temperature regulation of microbial communities that mediate anammox and denitrification was investigated in near shore permeable sediments at polar, temperate, and subtropical sites with annual mean temperatures ranging from -5 to 23 °C. Total N2 production rates were determined using the isotope pairing technique in intact core incubations under diffusive and simulated advection conditions and ranged from 2 to 359 μmol N m-2 d-1. For the majority of sites studied, N2 removal was 2-7 times more rapid under simulated advective flow conditions. Anammox comprised 6-14% of total N2 production at temperate and polar sites and was not detected at the subtropical site. Potential rates of denitrification and anammox were determined in anaerobic slurries in a temperature gradient block incubator across a temperature range of -1 °C to 42 °C. The highest optimum temperature (Topt) for denitrification was 36 °C and was observed in subtropical sediments, while the lowest Topt of 21 °C was observed at the polar site. Seasonal variation in the Topt was observed at the temperate site with values of 26 and 34 °C in winter and summer, respectively. The Topt values for anammox were 9 and 26 °C at the polar and temperate sites, respectively. The results demonstrate adaptation of denitrifying communities to in situ temperatures in permeable marine sediments across a wide range of temperatures, whereas marine anammox bacteria may be predominately psychrophilic to psychrotolerant. The adaptation of microbial communities to in situ temperatures suggests that the relationship between temperature and rates of N removal is highly dependent on community structure.

  18. [Distribution and influence factors of Anammox bacteria in sewage treatment systems].

    Science.gov (United States)

    Zheng, Bingyu; Peng, Yongzhen; Zhang, Liang; Yang, Anming; Zhang, Shujun

    2014-12-01

    Nitrogen removal techniques based on Anammox process are developing rapidly these years. The distribution and diversity of Anammox have become important research directions. A variety of Anammox have been detected till now, of which only Kuenenia and Brocadia are often detected in wastewater treatment systems. In addition, in a single niche there is only one type of Anammox bacteria. However, the distribution mechanism and transformation of Anammox bacteria in different niches are still ambiguous. Therefore, the distribution of Anammox in various conditions was summarized and analyzed in this article. And the key factors influencing the distribution of Anammox were concluded, including substrate concentration and the specific growth rate, sludge properties and microbial niche, the joint action and influence of multiple factors. The engineering significance research on the distribution and influencing factors of Anammox bacteria in the sewage system and proposed research prospects were expounded. PMID:26016371

  19. Biological Behavior of Anammox Process for Municipal Wastewater Treatment: Effect of Ammonia Removal and Other Parameters

    Directory of Open Access Journals (Sweden)

    R. Nabizadeh

    2012-09-01

    Full Text Available Historically, nitrogen compound due to major environmental and public health problems have been considered. Anaerobic ammonium oxidation processes were proposed by many advantages such as; novelty, promising method and cost-effective. In this work, we used of anommax process for a wastewater with high C:N ratios and the main parameter likes pH; temperature, NO2/NH4 ratio and behavior of COD, ammonium and nitrite during operation time of 55 days were evaluated. High efficiency in nitrite and ammonium removal is observed at pH values between 7.5 to 8 and operation times between 9 to 23 days. Furthermorethe variation of the nitrite/ammonium ratio done dependence to pH, and a higher ratio was associated with higher pH values. And lower values of NO2/NH4 ratio have occurred with decrease of pH at third phase of anommax process. The average elimination efficiency of COD was occurred about 89.22%, but the removal efficiency of COD in anommax reactor was obtained about 49.5%. Furthermorethe removal efficiency of ammonium and nitrite were provided about 50% for each.

  20. Source identification of nitrous oxide emission pathways from a single-stage nitritation-anammox granular reactor

    KAUST Repository

    Ali, Muhammad

    2016-06-16

    Nitrous oxide (N2O) production pathway in a signal-stage nitritation-anammox sequencing batch reactor (SBR) was investigated based on a multilateral approach including real-time N2O monitoring, N2O isotopic composition analysis, and in-situ analyses of spatial distribution of N2O production rate and microbial populations in granular biomass. N2O emission rate was high in the initial phase of the operation cycle and gradually decreased with decreasing NH4+ concentration. The average emission of N2O was 0.98 ± 0.42% and 1.35 ± 0.72% of the incoming nitrogen load and removed nitrogen, respectively. The N2O isotopic composition analysis revealed that N2O was produced via NH2OH oxidation and NO2− reduction pathways equally, although there is an unknown influence from N2O reduction and/or anammox N2O production. However, the N2O isotopomer analysis could not discriminate the relative contribution of nitrifier denitrification and heterotrophic denitrification in the NO2− reduction pathway. Various in-situ techniques (e.g. microsensor measurements and FISH (fluorescent in-situ hybridization) analysis) were therefore applied to further identify N2O producers. Microsensor measurements revealed that approximately 70% of N2O was produced in the oxic surface zone, where nitrifiers were predominantly localized. Thus, NH2OH oxidation and NO2 reduction by nitrifiers (nitrifier-denitrification) could be responsible for the N2O production in the oxic zone. The rest of N2O (ca. 30%) was produced in the anammox bacteria-dominated anoxic zone, probably suggesting that NO2− reduction by coexisting putative heterotrophic denitrifiers and some other unknown pathway(s) including the possibility of anammox process account for the anaerobic N2O production. Further study is required to identify the anaerobic N2O production pathways. Our multilateral approach can be useful to quantitatively examine the relative contributions of N2O production pathways. Good understanding of the key N2O

  1. Source identification of nitrous oxide emission pathways from a single-stage nitritation-anammox granular reactor.

    Science.gov (United States)

    Ali, Muhammad; Rathnayake, Rathnayake M L D; Zhang, Lei; Ishii, Satoshi; Kindaichi, Tomonori; Satoh, Hisashi; Toyoda, Sakae; Yoshida, Naohiro; Okabe, Satoshi

    2016-10-01

    Nitrous oxide (N2O) production pathway in a signal-stage nitritation-anammox sequencing batch reactor (SBR) was investigated based on a multilateral approach including real-time N2O monitoring, N2O isotopic composition analysis, and in-situ analyses of spatial distribution of N2O production rate and microbial populations in granular biomass. N2O emission rate was high in the initial phase of the operation cycle and gradually decreased with decreasing NH4(+) concentration. The average emission of N2O was 0.98 ± 0.42% and 1.35 ± 0.72% of the incoming nitrogen load and removed nitrogen, respectively. The N2O isotopic composition analysis revealed that N2O was produced via NH2OH oxidation and NO2(-) reduction pathways equally, although there is an unknown influence from N2O reduction and/or anammox N2O production. However, the N2O isotopomer analysis could not discriminate the relative contribution of nitrifier denitrification and heterotrophic denitrification in the NO2(-) reduction pathway. Various in-situ techniques (e.g. microsensor measurements and FISH (fluorescent in-situ hybridization) analysis) were therefore applied to further identify N2O producers. Microsensor measurements revealed that approximately 70% of N2O was produced in the oxic surface zone, where nitrifiers were predominantly localized. Thus, NH2OH oxidation and NO2 reduction by nitrifiers (nitrifier-denitrification) could be responsible for the N2O production in the oxic zone. The rest of N2O (ca. 30%) was produced in the anammox bacteria-dominated anoxic zone, probably suggesting that NO2(-) reduction by coexisting putative heterotrophic denitrifiers and some other unknown pathway(s) including the possibility of anammox process account for the anaerobic N2O production. Further study is required to identify the anaerobic N2O production pathways. Our multilateral approach can be useful to quantitatively examine the relative contributions of N2O production pathways. Good understanding of the

  2. The effect of nitrite inhibition on the anammox process.

    Science.gov (United States)

    Lotti, T; van der Star, W R L; Kleerebezem, R; Lubello, C; van Loosdrecht, M C M

    2012-05-15

    The negative effect of nitrite on anammox activity has been reported widely during the past decade. Although the adverse effect is clear, conflicting reports exist on the level at which it occurs and its reversible/irreversible nature. An in depth study on nitrite inhibition therefore was performed in which the influence of environmental factors was evaluated. Anammox activity was measured in anammox granules by continuously monitored standardized manometric batch tests extending the interpretation by evaluation of lag times, maximum conversion rates during the tests and substrates/product conversion ratios. The granules where obtained from a one-stage anammox reactor, the dominant anammox organisms belonged to the Brocadia type. The observed 50% activity inhibition for nitrite (IC(50)) was 0.4 g N L(-1). The activity recovered fully after removal of the nitrite. Conversion in fresh medium after exposure to up to 6 g NO(2)(-)-N L(-1) for 24 h showed less then 60% loss of activity. Presence of ammonium during nitrite (2 g N L(-1)) exposure resulted in a stronger loss of activity after nitrite exposure (50% and 30% in presence and absence of ammonium respectively). Presence of oxygen during nitrite incubation led to a maximum activity reduction of 32%. The recovery after exposure indicates that the adverse effect of nitrite is reversible and thus inhibitory rather than toxic in nature. Similarities between exposure at three different pH-values indicate that nitrite rather than nitrous acid is the actual inhibiting compound. PMID:22424965

  3. Anaerobic Removal of Ammonia Nitrogen by an Autotrophic Reactor with Fixed Film Opering in a Sequential Batch

    OpenAIRE

    Murilo C. Lucas; José H. A. Vasconcelos; Francisco Javier Cuba Téran; Carla Eloísa Diniz dos Santos

    2010-01-01

    This study presents results of ammonia nitrogen oxidation in absence of molecular oxygen. They were obtained after the operation of a sequential batch anaerobic reactor with fixed film. After the inoculation with sludge from an anaerobic stabilization pond of a slaughterhouse wastewater treatment plant, the reactor was fed with a synthetic culture media, as described by Martins (2007), in order to establish ideal conditions for growth and development of Anammox culture. The duration of the ba...

  4. Microbial Community Composition and Ultrastructure of Granules from a Full-Scale Anammox Reactor

    KAUST Repository

    Gonzalez-Gil, Graciela

    2014-12-11

    Granules in anammox reactors contain besides anammox bacteria other microbial communities whose identity and relationship with the anammox bacteria are not well understood. High calcium concentrations are often supplied to anammox reactors to obtain sufficient bacterial aggregation and biomass retention. The aim of this study was to provide the first characterization of bacterial and archaeal communities in anammox granules from a full-scale anammox reactor and to explore on the possible role of calcium in such aggregates. High magnification imaging using backscattered electrons revealed that anammox bacteria may be embedded in calcium phosphate precipitates. Pyrosequencing of 16S rRNA gene fragments showed, besides anammox bacteria (Brocadiacea, 32 %), substantial numbers of heterotrophic bacteria Ignavibacteriacea (18 %) and Anaerolinea (7 %) along with heterotrophic denitrifiers Rhodocyclacea (9 %), Comamonadacea (3 %), and Shewanellacea (3 %) in the granules. It is hypothesized that these bacteria may form a network in which heterotrophic denitrifiers cooperate to achieve a well-functioning denitrification system as they can utilize the nitrate intrinsically produced by the anammox reaction. This network may provide a niche for the proliferation of archaea. Hydrogenotrophic methananogens, which scavenge the key fermentation product H2, were the most abundant archaea detected. Cells resembling the polygon-shaped denitrifying methanotroph Candidatus Methylomirabilis oxyfera were observed by electron microscopy. It is hypothesized that the anammox process in a full-scale reactor triggers various reactions overall leading to efficient denitrification and a sink of carbon as biomass in anammox granules.

  5. 废水厌氧处理反应器功能拓展研究进展%Multifunctional role of anaerobic reactors in wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    徐恒; 汪翠萍; 王凯军

    2014-01-01

    inorganic pollutants could be further enhanced by ex-situ/in-situ methods. Recent studies also showed that calcium removal for water softening and in-situ biogas upgrading could be achieved through anaerobic reactors. Nevertheless, the research work of the above-mentioned field has appeared to be relatively independent and scattered so far. First, in this paper, the state of the art of anaerobic wastewater treatment and the traditional role of anaerobic reactors are summarized. Then, the expanded roles of anaerobic reactors in desulfurization, denitrification, phosphorus removal, softening treatment, and in-situ biogas upgrading were elaborately reviewed in terms of their feasibility and process description. A major problem for the anaerobic treatment of sulfate-contaminated wastewater is the production of hydrogen sulfide (H2S), which greatly inhibits the methanogenesis process. The introduction of the biological sulfide oxidation step could not only reduce sulfide toxicity, but could also recover sulfur in the form of the insoluble elemental sulfur. As for denitrification, the integration of methanogenesis with the traditional denitrification process or even the novel anaerobic ammonium oxidation (ANAMMOX) process has been proven to be able to remove organic pollutants and ammonia simultaneously. Phosphorus removal by physico-chemical and/or biological methods was also demonstrated in the anaerobic reactors; however, the involved mechanism and phosphorus transformation pathway need to be further investigated. High-strength of calcium ions was shown to have adverse impacts on the capacity and stability of both anaerobic reactors and post-treatment facilities. The combination of the stripping or crystallization devices with anaerobic reactors was effective at inducing precipitation of calcium carbonate to alleviate the inhibition of calcium ions. Problems due to the precipitation and accumulation of calcium carbonate in the anaerobic granules (hereafter referred to as the

  6. Genome-based microbial ecology of anammox granules in a full-scale wastewater treatment system.

    Science.gov (United States)

    Speth, Daan R; In 't Zandt, Michiel H; Guerrero-Cruz, Simon; Dutilh, Bas E; Jetten, Mike S M

    2016-01-01

    Partial-nitritation anammox (PNA) is a novel wastewater treatment procedure for energy-efficient ammonium removal. Here we use genome-resolved metagenomics to build a genome-based ecological model of the microbial community in a full-scale PNA reactor. Sludge from the bioreactor examined here is used to seed reactors in wastewater treatment plants around the world; however, the role of most of its microbial community in ammonium removal remains unknown. Our analysis yielded 23 near-complete draft genomes that together represent the majority of the microbial community. We assign these genomes to distinct anaerobic and aerobic microbial communities. In the aerobic community, nitrifying organisms and heterotrophs predominate. In the anaerobic community, widespread potential for partial denitrification suggests a nitrite loop increases treatment efficiency. Of our genomes, 19 have no previously cultivated or sequenced close relatives and six belong to bacterial phyla without any cultivated members, including the most complete Omnitrophica (formerly OP3) genome to date. PMID:27029554

  7. Genome-based microbial ecology of anammox granules in a full-scale wastewater treatment system

    Science.gov (United States)

    Speth, Daan R.; in 't Zandt, Michiel H.; Guerrero-Cruz, Simon; Dutilh, Bas E.; Jetten, Mike S. M.

    2016-01-01

    Partial-nitritation anammox (PNA) is a novel wastewater treatment procedure for energy-efficient ammonium removal. Here we use genome-resolved metagenomics to build a genome-based ecological model of the microbial community in a full-scale PNA reactor. Sludge from the bioreactor examined here is used to seed reactors in wastewater treatment plants around the world; however, the role of most of its microbial community in ammonium removal remains unknown. Our analysis yielded 23 near-complete draft genomes that together represent the majority of the microbial community. We assign these genomes to distinct anaerobic and aerobic microbial communities. In the aerobic community, nitrifying organisms and heterotrophs predominate. In the anaerobic community, widespread potential for partial denitrification suggests a nitrite loop increases treatment efficiency. Of our genomes, 19 have no previously cultivated or sequenced close relatives and six belong to bacterial phyla without any cultivated members, including the most complete Omnitrophica (formerly OP3) genome to date. PMID:27029554

  8. Effect of Different Fertilizer Treatments on Quantity of Soil Microbes and Structure of Ammonium Oxidizing Bacterial Community in a Calcareous Purple Paddy Soil

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The quantity of soil microbes and the structure of ammonium oxidizing bacterial (AOB) community were analyzed using the dilution plate counting and most probable number method (MPN), and denaturing gradient gel electrophoresis (DGGE), respectively. Fertilizer application tended to increase the number of soil microbes and alter the AOB community compared to the control with no fertilizer application (CK). Among the eight fertilizer treatments, soil samples from the treatments of mineral fertilizers (e.g., N, P, K) in combination with farmyard manure (M) had greater numbers of soil microbes and more complex structure of AOB community than those receiving mineral fertilizers alone. The principal component analyses (PCA) for ammonium oxidizing bacterial community structure showed that the eight fertilizer treatments could be divided into two PCA groups (PCA1 and PCA2). For the soil sampled after rice harvest, PCA1 included NP, NM, NPM and NPKM fertilizer treatments, while PCA2 was consisted of CK, N, M and NPK fertilizer treatments. For soil samples collected after wheat harvest, PCA1 was consisted of M, NM, NPM and NPKM fertilizer treatments, while PCA2 was composed of CK, N, NP and NPK fertilizer treatments. For a given rotation, the richness of AOB community in PCA1 was greater than that in PCA2. In addition, AOB community structure was more complex in the soil after rice harvest than that after wheat harvest. The results indicated that different fertilizer treatments resulted in substantial changes of soil microbe number and AOB community. Furthermore, mineral fertilizers (N, NP, NPK) combined with farmyard manure were effective for increasing the quantity of soil microbes, enriching AOB community, and improving the soil biofertility.

  9. 废水厌氧处理反应器功能拓展研究进展%Multifunctional role of anaerobic reactors in wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    徐恒; 汪翠萍; 王凯军

    2014-01-01

    inorganic pollutants could be further enhanced by ex-situ/in-situ methods. Recent studies also showed that calcium removal for water softening and in-situ biogas upgrading could be achieved through anaerobic reactors. Nevertheless, the research work of the above-mentioned field has appeared to be relatively independent and scattered so far. First, in this paper, the state of the art of anaerobic wastewater treatment and the traditional role of anaerobic reactors are summarized. Then, the expanded roles of anaerobic reactors in desulfurization, denitrification, phosphorus removal, softening treatment, and in-situ biogas upgrading were elaborately reviewed in terms of their feasibility and process description. A major problem for the anaerobic treatment of sulfate-contaminated wastewater is the production of hydrogen sulfide (H2S), which greatly inhibits the methanogenesis process. The introduction of the biological sulfide oxidation step could not only reduce sulfide toxicity, but could also recover sulfur in the form of the insoluble elemental sulfur. As for denitrification, the integration of methanogenesis with the traditional denitrification process or even the novel anaerobic ammonium oxidation (ANAMMOX) process has been proven to be able to remove organic pollutants and ammonia simultaneously. Phosphorus removal by physico-chemical and/or biological methods was also demonstrated in the anaerobic reactors; however, the involved mechanism and phosphorus transformation pathway need to be further investigated. High-strength of calcium ions was shown to have adverse impacts on the capacity and stability of both anaerobic reactors and post-treatment facilities. The combination of the stripping or crystallization devices with anaerobic reactors was effective at inducing precipitation of calcium carbonate to alleviate the inhibition of calcium ions. Problems due to the precipitation and accumulation of calcium carbonate in the anaerobic granules (hereafter referred to as the

  10. Ladderane Lipids in Anammox Bacteria: Occurence, Biosynthesis and Application as Environmental Markers

    OpenAIRE

    Rattray, J. E.

    2008-01-01

    Ladderane lipids are unusual membrane lipids of anammox bacteria, which contain either three or five cyclobutane rings, and are so far unique in nature. Anammox bacteria are recently identified members of the nitrogen cycle, with the ability to combine ammonium with nitrite to form dinitrogen gas, in waters or sediments containing little or no oxygen. In the natural environment they have been found in many different oxygen poor environments. For the first time, an anammox bacterium from the n...

  11. Hot topics and application trends of the anammox biotechnology: a review by bibliometric analysis

    OpenAIRE

    Zhang, Zuotao; Liu, Sitong

    2014-01-01

    Anammox has been extensively identified as a novel and sustained biotechnology for wastewater treatment. This study was conducted to evaluate the hot topics and application trends of anammox biotechnology by bibliometric analysis. The results show that “Water science and technology” and “Environmental science ecology” are the prevalent journal and category in this field. Many researches about “process” and “inhibition” have been carried out to conquer common challenges of anammox biotechnolog...

  12. Coexistence of nitrifying, anammox and denitrifying bacteria in a sequencing batch reactor

    OpenAIRE

    MichelaLangone; JiaYan

    2014-01-01

    Elevated nitrogen removal efficiencies from ammonium-rich wastewaters have been demonstrated by several applications, that combine nitritation and anammox processes. Denitrification will occur simultaneously when organic carbon is also present. In this study, the activity of aerobic ammonia oxidizing, anammox and denitrifying bacteria in a full scale Sequencing Batch Reactor, treating digester supernatants, was studied by means of batch-assays. AOB and anammox activities were maximum at pH of...

  13. Metatranscriptomics reveals the molecular mechanism of large granule formation in granular anammox reactor

    Science.gov (United States)

    Bagchi, Samik; Lamendella, Regina; Strutt, Steven; van Loosdrecht, Mark C. M.; Saikaly, Pascal E.

    2016-06-01

    Granules enriched with anammox bacteria are essential in enhancing the treatment of ammonia-rich wastewater, but little is known about how anammox bacteria grow and multiply inside granules. Here, we combined metatranscriptomics, quantitative PCR and 16S rRNA gene sequencing to study the changes in community composition, metabolic gene content and gene expression in a granular anammox reactor with the objective of understanding the molecular mechanism of anammox growth and multiplication that led to formation of large granules. Size distribution analysis revealed the spatial distribution of granules in which large granules having higher abundance of anammox bacteria (genus Brocadia) dominated the bottom biomass. Metatranscriptomics analysis detected all the essential transcripts for anammox metabolism. During the later stage of reactor operation, higher expression of ammonia and nitrite transport proteins and key metabolic enzymes mainly in the bottom large granules facilitated anammox bacteria activity. The high activity resulted in higher growth and multiplication of anammox bacteria and expanded the size of the granules. This conceptual model for large granule formation proposed here may assist in the future design of anammox processes for mainstream wastewater treatment.

  14. Metatranscriptomics reveals the molecular mechanism of large granule formation in granular anammox reactor

    KAUST Repository

    Bagchi, Samik

    2016-06-20

    Granules enriched with anammox bacteria are essential in enhancing the treatment of ammonia-rich wastewater, but little is known about how anammox bacteria grow and multiply inside granules. Here, we combined metatranscriptomics, quantitative PCR and 16S rRNA gene sequencing to study the changes in community composition, metabolic gene content and gene expression in a granular anammox reactor with the objective of understanding the molecular mechanism of anammox growth and multiplication that led to formation of large granules. Size distribution analysis revealed the spatial distribution of granules in which large granules having higher abundance of anammox bacteria (genus Brocadia) dominated the bottom biomass. Metatranscriptomics analysis detected all the essential transcripts for anammox metabolism. During the later stage of reactor operation, higher expression of ammonia and nitrite transport proteins and key metabolic enzymes mainly in the bottom large granules facilitated anammox bacteria activity. The high activity resulted in higher growth and multiplication of anammox bacteria and expanded the size of the granules. This conceptual model for large granule formation proposed here may assist in the future design of anammox processes for mainstream wastewater treatment.

  15. Effects of Inhibiting Acylated Homoserine Lactones (AHLs) on Anammox Activity and Stability of Granules'.

    Science.gov (United States)

    Zhao, Ran; Zhang, Hanmin; Zou, Xiang; Yang, Fenglin

    2016-07-01

    In this study, the effects of AHL-based QS signals on anammox activity and stability of granules' were investigated. Results clearly showed that the vanillin and porcine kidney acylase I could reduce the AHLs in anammox bacteria. Inactivation of AHLs by vanillin and porcine kidney acylase I depressed the nitrogen removal ability of anammox bacteria. A significant inhibition of specific anammox activity was observed when the concentration of vanillin and porcine kidney acylase I increased to 1 g/L. Anammox activity was depressed on enzyme level. Moreover, degradation of AHLs under vanillin and AHL-acylase exposure could result in anammox granules' disintegration. Further research showed that the contents of protein (PN) and polysaccharides (PS) in extracellular polymeric substances were reduced with AHLs blocked, and it further explained the instability and weakening strength of the anammox granules. The results of our investigation provided new insight into the AHL-based QS-regulated anammox activity, leading a potential way to enhance stability of anammox granules. PMID:27061587

  16. The Increasing Interest of ANAMMOX Research in China: Bacteria, Process Development, and Application

    Directory of Open Access Journals (Sweden)

    Mohammad Ali

    2013-01-01

    Full Text Available Nitrogen pollution created severe environmental problems and increasingly has become an important issue in China. Since the first discovery of ANAMMOX in the early 1990s, this related technology has become a promising as well as sustainable bioprocess for treating strong nitrogenous wastewater. Many Chinese research groups have concentrated their efforts on the ANAMMOX research including bacteria, process development, and application during the past 20 years. A series of new and outstanding outcomes including the discovery of new ANAMMOX bacterial species (Brocadia sinica, sulfate-dependent ANAMMOX bacteria (Anammoxoglobus sulfate and Bacillus benzoevorans, and the highest nitrogen removal performance (74.3–76.7 kg-N/m3/d in lab scale granule-based UASB reactors around the world were achieved. The characteristics, structure, packing pattern and floatation mechanism of the high-rate ANAMMOX granules in ANAMMOX reactors were also carefully illustrated by native researchers. Nowadays, some pilot and full-scale ANAMMOX reactors were constructed to treat different types of ammonium-rich wastewater including monosodium glutamate wastewater, pharmaceutical wastewater, and leachate. The prime objective of the present review is to elucidate the ongoing ANAMMOX research in China from lab scale to full scale applications, comparative analysis, and evaluation of significant findings and to set a design to usher ANAMMOX research in culmination.

  17. Microbial nitrogen transformation potential in surface run-off leachate from a tropical landfill

    International Nuclear Information System (INIS)

    Highlights: ► Microbial nitrogen transformations can alleviate toxic ammonium discharge. ► Aerobic ammonium oxidation was rate-limiting in Indonesian landfill leachate. ►Organic nitrogen ammonification was most dominant. ► Anaerobic nitrate reduction and ammonium oxidation potential were also high. ► A two-stage aerobic-anaerobic nitrogen removal system needs to be implemented. - Abstract: Ammonium is one of the major toxic compounds and a critical long-term pollutant in landfill leachate. Leachate from the Jatibarang landfill in Semarang, Indonesia, contains ammonium in concentrations ranging from 376 to 929 mg N L−1. The objective of this study was to determine seasonal variation in the potential for organic nitrogen ammonification, aerobic nitrification, anaerobic nitrate reduction and anaerobic ammonium oxidation (anammox) at this landfilling site. Seasonal samples from leachate collection treatment ponds were used as an inoculum to feed synthetic media to determine potential rates of nitrogen transformations. Aerobic ammonium oxidation potential (−1 h−1) was more than a hundred times lower than the anaerobic nitrogen transformation processes and organic nitrogen ammonification, which were of the same order of magnitude. Anaerobic nitrate oxidation did not proceed beyond nitrite; isolates grown with nitrate as electron acceptor did not degrade nitrite further. Effects of season were only observed for aerobic nitrification and anammox, and were relatively minor: rates were up to three times higher in the dry season. To completely remove the excess ammonium from the leachate, we propose a two-stage treatment system to be implemented. Aeration in the first leachate pond would strongly contribute to aerobic ammonium oxidation to nitrate by providing the currently missing oxygen in the anaerobic leachate and allowing for the growth of ammonium oxidisers. In the second pond the remaining ammonium and produced nitrate can be converted by a combination

  18. Anammox transited from denitrification in upflow biofilm reactor

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shao-hui; ZHENG Ping; HUA Yu-mei

    2004-01-01

    Anammox was successfully transited from heterotrophic denitrification and autotrophic denitrification in two upflow biofilm reactors, respectively. The results showed that the volumetric loading rate and nitrogen removal efficiency in the reactor transited from heterotrophic denitrification were higher than that in its counterpart. When the hydraulic retention time was 12 h or so, the total nitrogen loading rate was about 0.609 kg N/(m3·d), and the effluent ammonia and nitrite concentrations were less than 8.5 mg/L and 2.5 mg/L, respectively. The upflow anammox biofilm reactor was capable of keeping and accumulating the slow-growing bacteria efficiently. During operation of the reactor, the biomass color was gradually turned from brownish to red, and the ratio of ammonia consumption, nitrite consumption and nitrate production approached the theoretical one. These changes could be used as an indicator for working state of the reactor.

  19. Co-Occurring Anammox, Denitrification, and Codenitrification in Agricultural Soils

    OpenAIRE

    Long, Andrew; Heitman, Joshua; Tobias, Craig; Philips, Rebecca; Song, Bongkeun

    2013-01-01

    Anammox and denitrification mediated by bacteria are known to be the major microbial processes converting fixed N to N2 gas in various ecosystems. Codenitrification and denitrification by fungi are additional pathways producing N2 in soils. However, fungal codenitrification and denitrification have not been well investigated in agricultural soils. To evaluate bacterial and fungal processes contributing to N2 production, molecular and 15N isotope analyses were conducted with soil samples colle...

  20. Modelling and control design for SHARON/Anammox reactor sequence

    OpenAIRE

    Valverde Perez, Borja; Mauricio Iglesias, Miguel; Sin, Gürkan

    2012-01-01

    With the perspective of investigating a suitable control design for autotrophic nitrogen removal, this work presents a complete model of the SHARON/Anammox reactor sequence. The dynamics of the reactor were explored pointing out the different scales of the rates in the system: slow microbial metabolism against fast chemical reaction and mass transfer. Likewise, the analysis of the dynamics contributed to establish qualitatively the requirements for control of the reactors, both for regulation...

  1. Environmental evaluation of coexistence of denitrifying anaerobic methane-oxidizing archaea and bacteria in a paddy field.

    Science.gov (United States)

    Ding, Jing; Fu, Liang; Ding, Zhao-Wei; Lu, Yong-Ze; Cheng, Shuk H; Zeng, Raymond J

    2016-01-01

    The nitrate-dependent denitrifying anaerobic methane oxidation (DAMO) process, which is metabolized together by anaerobic methanotrophic archaea and NC10 phylum bacteria, is expected to be important for the global carbon and nitrogen cycles. However, there are little studies about the existence of this process and the functional microbes in environments. Therefore, the coexistence of DAMO archaea and bacteria in a paddy field was evaluated in this study. Next-generation sequencing showed that the two orders, Methanosarcinales and Nitrospirales, to which DAMO archaea and DAMO bacteria belong, were detected in the four soil samples. Then the in vitro experiments demonstrated both of nitrite- and nitrate-dependent DAMO activities, which confirmed the coexistence of DAMO archaea and DAMO bacteria. It was the first report about the coexistence of DAMO archaea and bacteria in a paddy field. Furthermore, anammox bacteria were detected in two of the four samples. The in vitro experiments did not show anammox activity in the initial period but showed low anammox activity after 20 days' enrichment. These results implicated that anammox bacteria may coexist with DAMO microorganisms in this field, but at a very low percentage. PMID:26394860

  2. Relating methanogen community structure and anaerobic digester function.

    Science.gov (United States)

    Bocher, B T W; Cherukuri, K; Maki, J S; Johnson, M; Zitomer, D H

    2015-03-01

    Much remains unknown about the relationships between microbial community structure and anaerobic digester function. However, knowledge of links between community structure and function, such as specific methanogenic activity (SMA) and COD removal rate, are valuable to improve anaerobic bioprocesses. In this work, quantitative structure-activity relationships (QSARs) were developed using multiple linear regression (MLR) to predict SMA using methanogen community structure descriptors for 49 cultures. Community descriptors were DGGE demeaned standardized band intensities for amplicons of a methanogen functional gene (mcrA). First, predictive accuracy of MLR QSARs was assessed using cross validation with training (n = 30) and test sets (n = 19) for glucose and propionate SMA data. MLR equations correlating band intensities and SMA demonstrated good predictability for glucose (q(2) = 0.54) and propionate (q(2) = 0.53). Subsequently, data from all 49 cultures were used to develop QSARs to predict SMA values. Higher intensities of two bands were correlated with higher SMA values; high abundance of methanogens associated with these two bands should be encouraged to attain high SMA values. QSARs are helpful tools to identify key microorganisms or to study and improve many bioprocesses. Development of new, more robust QSARs is encouraged for anaerobic digestion or other bioprocesses, including nitrification, nitritation, denitrification, anaerobic ammonium oxidation, and enhanced biological phosphorus removal. PMID:25562581

  3. Anaerobic bacteria

    Science.gov (United States)

    Brook I, Goldstein EJ. Diseases caused by non-spore forming anaerobic bacteria. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 297. Stedman's Online ...

  4. Hot topics and application trends of the anammox biotechnology: a review by bibliometric analysis.

    Science.gov (United States)

    Zhang, Zuotao; Liu, Sitong

    2014-01-01

    Anammox has been extensively identified as a novel and sustained biotechnology for wastewater treatment. This study was conducted to evaluate the hot topics and application trends of anammox biotechnology by bibliometric analysis. The results show that "Water science and technology" and "Environmental science ecology" are the prevalent journal and category in this field. Many researches about "process" and "inhibition" have been carried out to conquer common challenges of anammox biotechnology in its actual engineering application. "Fluorescence in situ hybridization" continues to be the leading rRNA microbiological analysis method after its first application. Most importantly, "Completely autotrophic nitrogen removal over nitrite (CANON)", "Sequencing batch reactors (SBR) for anammox operation", "black water treatment" and "anammox biofilm" are identified as the prevalent process type, reactor type, wastewater type and bacterial aggregation form in anammox research currently, which forecasts the further engineering application direction of anammox biotechnology. The study will be useful for the researchers to acquaint the current state and the application trends in anammox biotechnology field. PMID:24855588

  5. Differentiation in the microbial ecology and activity of suspended and attached bacteria in a nitritation-anammox process.

    Science.gov (United States)

    Park, Hongkeun; Sundar, Suneethi; Ma, Yiwei; Chandran, Kartik

    2015-02-01

    A directed differentiation between the biofilm and suspension was observed in the molecular microbial ecology and gene expression of different bacteria in a biofilm nitritation-anammox process operated at varying hydraulic residence times (HRT) and nitrogen loading rates (NLR). The highest degree of enrichment observed in the biofilm was of anaerobic ammonia-oxidizing bacteria (AMX) followed by that of Nitrospira spp. related nitrite-oxidizing bacteria (NOB). For AMX, a major shift from Candidatus "Brocadia fulgida" to Candidatus "Kuenenia stuttgartiensis" in both suspension and biofilm was observed with progressively shorter HRT, using discriminatory biomarkers targeting the hydrazine synthase (hzsA) gene. In parallel, expression of the hydrazine oxidoreductase gene (hzo), a functional biomarker for AMX energy metabolism, became progressively prominent in the biofilm. A marginal but statistically significant enrichment in the biofilm was observed for Nitrosomonas europaea related ammonia-oxidizing bacteria (AOB). In direct contrast to AMX, the gene expression of ammonia monooxygenase subunit A (amoA), a functional biomarker for AOB energy metabolism, progressively increased in suspension. Using gene expression and biomass concentration measures in conjunction, it was determined that signatures of AOB metabolism were primarily present in the biofilm throughout the study. On the other hand, AMX metabolism gradually shifted from being uniformly distributed in both the biofilm and suspension to primarily the biofilm at shorter HRTs and higher NLRs. These results therefore highlight the complexity and key differences in the microbial ecology, gene expression and activity between the biofilm and suspension of a nitritation-anammox process and the biokinetic and metabolic drivers for such niche segregation. PMID:25115980

  6. Modelling and control design for SHARON/Anammox reactor sequence

    DEFF Research Database (Denmark)

    Valverde Perez, Borja; Mauricio Iglesias, Miguel; Sin, Gürkan

    2012-01-01

    With the perspective of investigating a suitable control design for autotrophic nitrogen removal, this work presents a complete model of the SHARON/Anammox reactor sequence. The dynamics of the reactor were explored pointing out the different scales of the rates in the system: slow microbial...... metabolism against fast chemical reaction and mass transfer. Likewise, the analysis of the dynamics contributed to establish qualitatively the requirements for control of the reactors, both for regulation and for optimal operation. Work in progress on quantitatively analysing different control structure...

  7. Microbial biomarkers from the East China Sea and implications for paleoenvironmental reconstructions

    Science.gov (United States)

    Zhao, M.; Hu, W. J.; Duan, S. S.; Cao, L. Y.; Wang, Y. Y.; Zhao, S. Z.; Xing, L.

    2015-12-01

    We report the vertical and spatial distributions of isoprenoid glycerol dibiphytanyl glycerol tetraethers (GDGTs), ladderanes and phytoplankton biomarkers in suspended particulates from the East China Sea (ECS) to evaluate the living habitat and environments of the planktonic archaea Thaumarchaeota and anaerobic ammonium oxidation (anammox) bacteria, respectively. Maximum GDGT concentration mostly occurred in bottom waters while maximum phytoplankton biomarker concentration occurred in the surface layers; and these results from the ECS provides further evidence for the use of the TEX86 index as a proxy for bottom water temperature in shallow shelf sea environments. Ladderanes were detected in both surface and subsurface particulates, suggesting that anammox activity was widespread in both the hypoxia zone near the Changjiang Estuary and in the mid-shelf of the ECS. Thus, anaerobic condition is not a requirement for anammox bacteria; however, ladderane-derived anammox activity was higher in lower oxygen environments, confirming ladderanes as useful proxies for reconstructing hypoxia changes. Statistical analysis will be presented to assess the link between archaea (Thaumarchaeota) performing aerobic ammonia oxidation and bacteria (anammox) performing anaerobic ammonium oxidation in the ECS, the implications for both carbon and nitrogen cycles.

  8. Biphasic Behavior of Anammox Regulated by Nitrite and Nitrate in an Estuarine Sediment

    OpenAIRE

    Trimmer, Mark; Nicholls, Joanna C.; Morley, Nicholas; Davies, Christian A.; Aldridge, John

    2005-01-01

    The production of N2 gas via anammox was investigated in sediment slurries at in situ NO2− concentrations in the presence and absence of NO3−. With single enrichment above 10 μM 14NO2− or 14NO3− and 15NH4+, anammox activity was always linear (P < 0.05), in agreement with previous findings. In contrast, anammox exhibited a range of activity below 10 μM NO2− or NO3−, including an elevated response at lower concentrations. With 100 μM NO3−, no significant transient accumulation of NO2− could be ...

  9. One-stage partial nitritation and anammox in membrane bioreactor.

    Science.gov (United States)

    Huang, Xiaowu; Sun, Kaihang; Wei, Qiaoyan; Urata, Kohei; Yamashita, Yuki; Hong, Nian; Hama, Takehide; Kawagoshi, Yasunori

    2016-06-01

    Partial nitritation and anammox (PN/A) was applied in a lab-scale membrane bioreactor (MBR) to investigate its technical feasibility for treating ammonium-rich wastewater with low C/N ratio. The bacterial community was analyzed by molecular cloning and 16S rRNA sequence analysis. Partial nitritation (PN) was first realized in MBR by seeding aerobic activated sludge. With dissolved oxygen control, a steady effluent mixture with NO2 (-)-N/NH4 (+)-N ratio of 1.13 ± 0.08 was generated from the PN process. Subsequently, the MBR was seeded with anammox biomass on day 59. After running 300 days, the one-stage PN/A achieved a maximum nitrogen removal rate of 1.45 kg N/m(3)/day at the nitrogen removal efficiency of 89.5 %. Microbial community analysis revealed that Nitrosomonas sp. HKU and Nitrosospira sp. YKU corresponded to nitritation; meanwhile, Candidatus Brocadia TKU sp. accounted for nitrogen removal of the PN/A system. Specifically, Nitrosomonas sp. were enriched in the reactor at the PN/A phase and then conquered Nitrosospira sp. to be the predominant ammonia oxidizers. Nitrite oxidizers and denitrifiers were detected in symbiosis with aforementioned microbes. Denitrification promised potential plus nitrogen depletion. The present one-stage PN/A process allows a significant decrease in operational costs compared with classical nitrification/denitrification. PMID:26916267

  10. Transformation processes of nitrogen, phosphorus and iron in sub-euphotic waters and surface sediments

    OpenAIRE

    Sokoll, Sarah

    2013-01-01

    In the ocean, concentrations and ratios of nitrogen (N), phosphorus (P) and iron (Fe) determine primary production. In upwelling regions, nutrient-rich deep waters fuel this primary production. Knowledge of nutrient transformation processes in deep waters is still scarce. Therefore N-removal via denitrification and anaerobic ammonium oxidation (anammox) as well as P and Fe transformation processes were investigated. In the Arabian Sea up to 50% of N-loss was due to benthic N-removal, emphasiz...

  11. Anaerobic workout

    OpenAIRE

    McAdam, Ewan J.

    2010-01-01

    Anaerobic technology cannot directly replace current wastewater treatment processes exclusively. The UASB reactor configuration removes slightly less organic carbon by comparison as the process relies on lamella separation for passive clarification rather than using fine pores like anMBR. By contrast, whilst anMBR can operate as a single unit process for organic carbon removal, the membrane surface has to be cleaned using gas sparging to limit surface deposition, which requires extra energy. ...

  12. Discrepant membrane fouling of partial nitrification and anammox membrane bioreactor operated at the same nitrogen loading rate.

    Science.gov (United States)

    Niu, Zhao; Zhang, Zuotao; Liu, Sitong; Miyoshi, Taro; Matsuyama, Hideo; Ni, Jinren

    2016-08-01

    In this study, two times more serious membrane fouling was found in anammox membrane bioreactor, compared to partial nitrification membrane bioreactor (PN-MBR) operated at the same nitrogen loading rate. By protein, polysaccharide, amino acids and functional groups analysis, it was found that the discrepancy in membrane fouling was virtually due to the difference in microbial products of nitrifiers and anammox bacteria. Protein and polysaccharide were main foulants on membrane surface; meanwhile theirs content and ratio in the EPS, supernatant and membrane surface were significantly different in PN-MBR and anammox-MBR. The anammox metabolism products contained much more hydrophobic organics, hydrophobic amino acids, and hydrophobic functional groups than nitrifiers. A mass of anammox bacteria as well as hydrophobic metabolism products deposited on the hydrophobic membrane surface and formed serious fouling. In further, hydrophilic modification is more urgently needed to mitigate membrane fouling when running anammox-MBR, than PN-MBR. PMID:27209455

  13. Performance and control of biofilm systems with partial nitritation and Anammox for supernatant treatment

    OpenAIRE

    Szatkowska, Beata

    2007-01-01

    Separate treatment of supernatant with dewatering of digested sludge with application of partial nitritation/Anammox process is assessed to be a cost-effective way to remove about 10-15% of influent nitrogen and, thereby, facilitate possibilities to reach required effluent requirements from the plant. The combined partial nitritation/Anammox process can be performed in two separate reactors or in one-stage. Both process options have been investigated in technical- and laboratory-scale pilot p...

  14. Ammonium removal from municipal wastewater with application of ion exchange and partial nitritation/Anammox process

    OpenAIRE

    Malovanyy, Andriy

    2014-01-01

    Nitrogen removal from municipal wastewater with application of Anammox process offers cost reduction, especially if it is combined with maximal use of organic content of wastewater for biogas production. In this study a new technology is proposed, which is based on ammonium concentration from municipal wastewater by ion exchange followed by biological removal of ammonium from the concentrated stream by partial nitritation/Anammox process. In experiments on ammonium concentration four the most...

  15. Nitrogen removal by anammox and denitrification in a subtropical seagrass ecosystem

    Science.gov (United States)

    Salk, K.; Ostrom, N. E.; Erler, D.; Eyre, B.; Carlson-Perret, N.

    2015-12-01

    Anammox is now recognized as a globally important process that may rival denitrification in its removal of inorganic N from aquatic systems. Owing to its fairly recent discovery, however, measurements of anammox in coastal environments are sparse. This study measured the N removal processes, denitrification and anammox, in a seagrass ecosystem in New South Wales, Australia, using a modified version of the isotope pairing technique. This previously published method has yet to be applied to seagrass environments and relies on the measurement of both N2O and N2 to calculate rates of anammox and denitrification. Intact sediment cores were incubated under in situ conditions and amended with 15N-NO3- as a tracer. The role of organic C quality in controlling N removal rates was evaluated through addition of seagrass or phytoplankton detritus. In control cores (i.e., no C addition), the total N removal rate was 0.48 ± 0.22 μmol N m-2 h-1. These are among the lowest rates measured in seagrasses and other coastal areas. N removal rates were stimulated when seagrass detritus was added (3.3 times higher than control) whereas the addition of phytoplankton detritus did not stimulate N removal. This is surprising, as phytoplankton detritus is generally a more labile C source than seagrass detritus. These results indicate that the microbial community responds more quickly to organic matter they are conditioned to process. Regardless of C treatment, anammox made up a greater proportion of N2 production (71 ± 16%) than denitrification (24 ± 13%), in contrast to most other studies. The high proportion of anammox-derived N2 production implies that previous N removal rates measured in other systems without anammox inclusion could be significantly underestimated.

  16. Anaerobic thermophiles.

    Science.gov (United States)

    Canganella, Francesco; Wiegel, Juergen

    2014-01-01

    The term "extremophile" was introduced to describe any organism capable of living and growing under extreme conditions. With the further development of studies on microbial ecology and taxonomy, a variety of "extreme" environments have been found and an increasing number of extremophiles are being described. Extremophiles have also been investigated as far as regarding the search for life on other planets and even evaluating the hypothesis that life on Earth originally came from space. The first extreme environments to be largely investigated were those characterized by elevated temperatures. The naturally "hot environments" on Earth range from solar heated surface soils and water with temperatures up to 65 °C, subterranean sites such as oil reserves and terrestrial geothermal with temperatures ranging from slightly above ambient to above 100 °C, to submarine hydrothermal systems with temperatures exceeding 300 °C. There are also human-made environments with elevated temperatures such as compost piles, slag heaps, industrial processes and water heaters. Thermophilic anaerobic microorganisms have been known for a long time, but scientists have often resisted the belief that some organisms do not only survive at high temperatures, but actually thrive under those hot conditions. They are perhaps one of the most interesting varieties of extremophilic organisms. These microorganisms can thrive at temperatures over 50 °C and, based on their optimal temperature, anaerobic thermophiles can be subdivided into three main groups: thermophiles with an optimal temperature between 50 °C and 64 °C and a maximum at 70 °C, extreme thermophiles with an optimal temperature between 65 °C and 80 °C, and finally hyperthermophiles with an optimal temperature above 80 °C and a maximum above 90 °C. The finding of novel extremely thermophilic and hyperthermophilic anaerobic bacteria in recent years, and the fact that a large fraction of them belong to the Archaea has definitely

  17. Anaerobic Thermophiles

    Directory of Open Access Journals (Sweden)

    Francesco Canganella

    2014-02-01

    Full Text Available The term “extremophile” was introduced to describe any organism capable of living and growing under extreme conditions. With the further development of studies on microbial ecology and taxonomy, a variety of “extreme” environments have been found and an increasing number of extremophiles are being described. Extremophiles have also been investigated as far as regarding the search for life on other planets and even evaluating the hypothesis that life on Earth originally came from space. The first extreme environments to be largely investigated were those characterized by elevated temperatures. The naturally “hot environments” on Earth range from solar heated surface soils and water with temperatures up to 65 °C, subterranean sites such as oil reserves and terrestrial geothermal with temperatures ranging from slightly above ambient to above 100 °C, to submarine hydrothermal systems with temperatures exceeding 300 °C. There are also human-made environments with elevated temperatures such as compost piles, slag heaps, industrial processes and water heaters. Thermophilic anaerobic microorganisms have been known for a long time, but scientists have often resisted the belief that some organisms do not only survive at high temperatures, but actually thrive under those hot conditions. They are perhaps one of the most interesting varieties of extremophilic organisms. These microorganisms can thrive at temperatures over 50 °C and, based on their optimal temperature, anaerobic thermophiles can be subdivided into three main groups: thermophiles with an optimal temperature between 50 °C and 64 °C and a maximum at 70 °C, extreme thermophiles with an optimal temperature between 65 °C and 80 °C, and finally hyperthermophiles with an optimal temperature above 80 °C and a maximum above 90 °C. The finding of novel extremely thermophilic and hyperthermophilic anaerobic bacteria in recent years, and the fact that a large fraction of them belong

  18. Treatment of nitrogen-rich wastewater using partial nitrification and anammox in the CANON process.

    Science.gov (United States)

    Third, K A; Paxman, J; Schmid, M; Strous, M; Jetten, M S M; Cord-Ruwisch, R

    2005-01-01

    Partial nitrification combined with Anammox in a single reactor (the CANON process) is an energy-efficient N-removal technology that could substantially lower the N-load of a WWTP by separate treatment of nitrogen-rich side streams, preventing the need for extensive expansion and reducing the total energy requirement. This study looks at the enrichment of Anammox from activated sludge and its application in the CANON process on lab-scale. The aim was to identify the critical process control parameters necessary for successful operation of CANON. An Anammox culture capable of removing 0.6 kg N/m3/d was enriched in 14 weeks in a sequencing batch reactor. Nitrifying biomass was inoculated into the Anammox reactor (10% v/v) together with limited oxygen supply (culture. The small flocs formed by the biomass (< 1000 microm) were sensitive to low O2 concentrations (< 0.1 mg/L) which prevented simultaneous nitrification and Anammox. Operation with 20 min aerobiosis and 30 min anaerobiosis was necessary to achieve sustained, completely autotrophic N-removal for an extended period at a rate of 0.08 kg N/m3/d. Essential process control parameters for stable CANON operation were the nitrite concentration, oxygen concentration, pH and the temperature. PMID:16235745

  19. Aerobic Microbial Respiration In Oceanic Oxygen Minimum Zones

    DEFF Research Database (Denmark)

    Kalvelage, Tim; Lavik, Gaute; Jensen, Marlene Mark;

    2015-01-01

    denitrification and alternative anaerobic pathways of organic matter remineralization cannot account for the ammonium requirements of reported anammox rates. Here, we explore the significance of microaerobic respiration as a source of ammonium during organic matter degradation in the oxygen-deficient waters off...... and laterally advected, oxygenated waters in this zone by aerobic microorganisms. In accordance, metagenomic and metatranscriptomic analyses identified genes encoding for aerobic terminal oxidases and demonstrated their expression by diverse microbial communities, even in virtually anoxic waters. Our......Oxygen minimum zones are major sites of fixed nitrogen loss in the ocean. Recent studies have highlighted the importance of anaerobic ammonium oxidation, anammox, in pelagic nitrogen removal. Sources of ammonium for the anammox reaction, however, remain controversial, as heterotrophic...

  20. Anaerobic Digestion: Process

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Batstone, Damien J.

    2011-01-01

    Organic waste may degrade anaerobically in nature as well as in engineered systems. The latter is called anaerobic digestion or biogasification. Anaerobic digestion produces two main outputs: An energy-rich gas called biogas and an effluent. The effluent, which may be a solid as well as liquid with...... very little dry matter may also be called a digest. The digest should not be termed compost unless it specifically has been composted in an aerated step. This chapter describes the basic processes of anaerobic digestion. Chapter 9.5 describes the anaerobic treatment technologies, and Chapter 9.......6 addresses the mass balances and environmental aspects of anaerobic digestion....

  1. [Effect of gas-lift device on nitrogen removal efficiency of ANAMMOX reactor ].

    Science.gov (United States)

    Xiang, Li; Zhang, Da-lini; Huang, Yong; Chen, Zong-heng; Yuan, Yi

    2014-09-01

    The effect of air-lift device on the nitrogen removal efficiency of ANAMMOX reactor was studied by increasing the substrate concentration to improve nitrogen load rate and inoculate ANAMMOX sludge. The results showed that the effluent recirculation was achieved by using nitrogen gas produced from the ANAMMOX process as power in the air-lift room. With the increase of nitrogen removal rate, the rate of effluent recirculation was increased, which diluted influent substrate concentration and alleviated the inhibition of ANAMMOX bacteria,. After 183 d operation, the effluent NH4+ -N and NO2- -N concentrations were increased to 46. 3 mg L-1 and 53.21 mg.L-1, and the nitrogen removal rate was kept stable at 28.3 kg (m3.d)-1, when the influent NH4+ -N and NO2- -N concentrations were increased to 700 mg.L-1 and 840 mgL-1, respectively. The effluent recirculation system formed by gas-lift devices is an economic and effective solution to the inhibition caused by high substrate concentration in traditional reactor, meanwhile, the power consumption of the external reflux pump was reduced. PMID:25518664

  2. Oxygen sensitivity of anammox and coupled N-cycle processes in oxygen minimum zones

    DEFF Research Database (Denmark)

    Kalvelage, Tim; Jensen, Marlene Mark; Contreras, Sergio;

    2011-01-01

    Nutrient measurements indicate that 30–50% of the total nitrogen (N) loss in the ocean occurs in oxygen minimum zones (OMZs). This pelagic N-removal takes place within only ,0.1% of the ocean volume, hence moderate variations in the extent of OMZs due to global warming may have a large impact on...... the global N-cycle. We examined the effect of oxygen (O2) on anammox, NH3 oxidation and NO3 2 reduction in 15N-labeling experiments with varying O2 concentrations (0–25 mmol L21) in the Namibian and Peruvian OMZs. Our results show that O2 is a major controlling factor for anammox activity in OMZ...... waters. Based on our O2 assays we estimate the upper limit for anammox to be ,20 mmol L21. In contrast, NH3 oxidation to NO2 2 and NO3 2 reduction to NO2 2 as the main NH4 + and NO2 2 sources for anammox were only moderately affected by changing O2 concentrations. Intriguingly, aerobic NH3 oxidation was...

  3. Continuous-flow combined process of nitritation and ANAMMOX for treatment of landfill leachate.

    Science.gov (United States)

    Wang, Zhong; Peng, Yongzhen; Miao, Lei; Cao, Tianhao; Zhang, Fangzhai; Wang, Shuying; Han, Jinhao

    2016-08-01

    Due to the difficulty in removing nitrogen from landfill leachate, a combined continuous-flow process of nitritation and anammox was applied to process mature leachate. The transformation rate of ammonia and nitrite accumulation ratio in A/O reactor were kept above 95% and 92% respectively through associated inhibition of free ammonia (FA) and free nitrous acid (FNA) to NOB. The total nitrogen volumetric load of anammox in an UASB reactor was brought up from 0.5kg/(m(3)·d) to 1.2kg/(m(3)·d) by gradually increasing influent substrate concentration and reducing hydraulic retention time (HRT). The results show that COD from mature leachate did not bring obvious inhibition effects to anammox. Under concentrations of influent ammonia and COD which were respectively 1330mg/L and 2250mg/L, the removal efficiencies of TN and COD reached 94% and 62% respectively. In the quantitative PCR reactions, the proportions occupied by AOB, NOB and anammox in A/O were 11.39%, 1.76% and 0.05% respectively; and proportions of those in UASB were 0.35%, 4.01% and 7.78% respectively. PMID:27176671

  4. Kinetic models for nitrogen inhibition in ANAMMOX and nitrification process on deammonification system at room temperature

    Science.gov (United States)

    The performance of the deammonification process depends on the microbial activity of ammonia oxidizing bacteria (AOB) and ANAMMOX bacteria. These autotrophic organisms have different preferences for substrate, operating conditions and some external factors that may cause inhibition or imbalance of t...

  5. Preliminary research on the anammox process and control of nitrogen compounds in a recirculating aquaculture system

    Directory of Open Access Journals (Sweden)

    Savin Cristian

    2013-01-01

    Full Text Available Using anammox process in biological filtration of technological water within recirculatingaquaculture system is an alternative to nitrification / denitrification process which can reduce productioncosts, especially energy by replacing aerobic biological processes that require high oxygen consumption,provided through the addition for optimal function of biofilter (conversion of N-NH4 and N-NO2. Aim ofthis paper is to highlight the first steps in the control of nitrogen compounds in recirculating aquaculturesystems using anammox process. Data shown are obtained after 78 researching days (research stillongoing, the results being encouraging, registering an ammonium removal efficiency of 77% in SC1 andof 32% in SC2. Nitrites registered an increase in SC1 and a decrease in SC2 and there are allprerequisites showing that in SC2 anammox activity is more advanced than in SC1. The average ofoxygen consumption rate was 0.73 mgL-1 in SC1 smaller than 0.99 mgL-1 from SC2, which reinforces theidea that there are anammox process in SC2.

  6. Anaerobic ammonia removal in presence of organic matter: A novel route

    International Nuclear Information System (INIS)

    This study describes the feasibility of anaerobic ammonia removal process in presence of organic matter. Different sources of biomass collected from diverse eco-systems containing ammonia and organic matter (OM) were screened for potential anaerobic ammonia removal. Sequential batch studies confirmed the possibility of anaerobic ammonia removal in presence of OM, but ammonia was oxidized anoxically to nitrate (at oxidation reduction potential; ORP -248 ± 25 mV) by an unknown mechanism unlike in the reported anammox process. The oxygen required for oxidation of ammonia might have been generated through catalase enzymatic activity of facultative anaerobes in mixed culture. The oxygen generation possibility by catalase enzyme route was demonstrated. Among the inorganic electron acceptors (NO2-, NO3- and SO42-) studied, NO2- was found to be most effective in total nitrogen removal. Denitrification by the developed culture was much effective and faster compared to ammonia oxidation. The results of this study show that anaerobic ammonia removal is feasible in presence of OM. The novel nitrogen removal route is hypothesized as enzymatic anoxic oxidation of NH4+ to NO3-, followed by denitrification via autotrophic and/or heterotrophic routes. The results of batch study were confirmed in continuous reactor operation

  7. Biological nutrients removal from the supernatant originating from the anaerobic digestion of the organic fraction of municipal solid waste.

    Science.gov (United States)

    Malamis, S; Katsou, E; Di Fabio, S; Bolzonella, D; Fatone, F

    2014-09-01

    This study critically evaluates the biological processes and techniques applied to remove nitrogen and phosphorus from the anaerobic supernatant produced from the treatment of the organic fraction of municipal solid waste (OFMSW) and from its co-digestion with other biodegradable organic waste (BOW) streams. The wide application of anaerobic digestion for the treatment of several organic waste streams results in the production of high quantities of anaerobic effluents. Such effluents are characterized by high nutrient content, because organic and particulate nitrogen and phosphorus are hydrolyzed in the anaerobic digestion process. Consequently, adequate post-treatment is required in order to comply with the existing land application and discharge legislation in the European Union countries. This may include physicochemical and biological processes, with the latter being more advantageous due to their lower cost. Nitrogen removal is accomplished through the conventional nitrification/denitrification, nitritation/denitritation and the complete autotrophic nitrogen removal process; the latter is accomplished by nitritation coupled with the anoxic ammonium oxidation process. As anaerobic digestion effluents are characterized by low COD/TKN ratio, conventional denitrification/nitrification is not an attractive option; short-cut nitrogen removal processes are more promising. Both suspended and attached growth processes have been employed to treat the anaerobic supernatant. Specifically, the sequencing batch reactor, the membrane bioreactor, the conventional activated sludge and the moving bed biofilm reactor processes have been investigated. Physicochemical phosphorus removal via struvite precipitation has been extensively examined. Enhanced biological phosphorus removal from the anaerobic supernatant can take place through the sequencing anaerobic/aerobic process. More recently, denitrifying phosphorus removal via nitrite or nitrate has been explored. The removal of

  8. Seasonality and depth distribution of the abundance and activity of ammonia oxidizing microorganisms in marine coastal sediments (North Sea

    Directory of Open Access Journals (Sweden)

    Yvonne Antonia Lipsewers

    2014-09-01

    Full Text Available Microbial processes such as nitrification and anaerobic ammonium oxidation (anammox are important for nitrogen cycling in marine sediments. Seasonal variations of archaeal and bacterial ammonia oxidizers (AOA and AOB and anammox bacteria, as well as the environmental factors affecting these groups, are not well studied. We have examined the seasonal and depth distribution of the abundance and potential activity of these microbial groups in coastal marine sediments of the southern North Sea. This was achieved by quantifying specific intact polar lipids (IPLs as well as the abundance and gene expression of their 16S rRNA gene, the ammonia monooxygenase subunit A (amoA gene of AOA and AOB, and the hydrazine synthase (hzsA gene of anammox bacteria. AOA, AOB and anammox bacteria were detected and transcriptionally active down to 12 cm sediment depth. In all seasons, the abundance of AOA was higher compared to the AOB abundance suggesting that AOA play a more dominant role in aerobic ammonia oxidation in these sediments. Anammox bacteria were abundant and active even in oxygenated and bioturbated parts of the sediment. The abundance of AOA and AOB was relatively stable with depth and over the seasonal cycle, while anammox bacteria abundance and transcriptional activity were highest in August. North Sea sediments thus seem to provide a common, stable, ecological niche for AOA, AOB and anammox bacteria.

  9. Effects of intermittent starvation on preservation characteristics of ANAMMOX bacteria%间歇性饥饿对厌氧氨氧化菌混培物保藏特性的影响

    Institute of Scientific and Technical Information of China (English)

    汪彩华; 郑平; 唐崇俭; 陈婷婷

    2013-01-01

    The effects of intermittent starvation on preservation characteristics of anammox bacteria were studied using three different preservation methods, which contained 4℃, 4℃ with addition of substrate ( NO2- -N/NH4+ -N ratio of 1. 32) every ten days and 4℃ with addition of substrate ( NO2- -N/ NH4+ -N ratio of 1.63) every ten days. Results indicated that intermittent starvation was more harmful to anammox bacteria than that of the long-term continuous starvation under anaerobic conditions. Besides, it could be found that the higher concentration of nitrite would have stronger inhibiting effects on the preservation of anammox bacteria. In addition, the anammox bacterial activities were directly correlated with the content of heme c. The color of anammox bacteria could reflect the relative bacterial activities as well as heme c content under the conditions without deliberate color interference. Further, results also showed that the particle structure and the extracellular polymers of anammox bacteria would help to increase the resistance of bacteria to adverse factors. During the 5-month preservations, all the activity decaying rates of the three methods decreased fast initially, and then slowed down to relatively stable values with survival activity percentages of 75. 3% , 70.8% and 62. 7% , respectively.%厌氧条件下,采用4℃、4℃并每隔10 d换1次NO-2-N/NH+4-N浓度比为1.32的基质、4℃并每隔10 d换1次NO-2-N/NH+4-N浓度比为1.63的基质3种方法保藏厌氧氨氧化菌混培物,研究间歇性饥饿对厌氧氨氧化菌混培物保藏特性的影响.结果表明,间歇性饥饿对厌氧氨氧化菌混培物的危害大于长期性饥饿,且亚硝态氮浓度越高危害越大;另厌氧氨氧化菌混培物活性还与血红素c含量有直接相关性,无外界颜色干扰时厌氧氨氧化菌混培物颜色还可直观反映其活性和血红素c含量,且厌氧氨氧化菌混培物的颗粒结构及其富含的胞外多聚物能增强

  10. Coexistence of nitrifying, anammox and denitrifying bacteria in a sequencing batch reactor

    Directory of Open Access Journals (Sweden)

    Michela eLangone

    2014-02-01

    Full Text Available Elevated nitrogen removal efficiencies from ammonium-rich wastewaters have been demonstrated by several applications, that combine nitritation and anammox processes. Denitrification will occur simultaneously when organic carbon is also present. In this study, the activity of aerobic ammonia oxidizing, anammox and denitrifying bacteria in a full scale Sequencing Batch Reactor, treating digester supernatants, was studied by means of batch-assays. AOB and anammox activities were maximum at pH of 8.0 and 7.8-8.0, rispectively. Short term effect of nitrite on anammox activity was studied, showing nitrite up to 42 mg/L did not result in inhibition. Both denitrification via nitrate and nitrite were measured. To reduce nitrite-oxidizing activity, high of NH3 – N (1.9-10 mg N-NH3/L and low nitrite (3-8 mg TNN/L are required conditions during the whole SBR cycle.Molecular analysis showed the nitritation-anammox sludge harbored a high microbial diversity, where each microorganism has a specific role. Using ammonia monooxygenase α –subunit (amoA gene as a marker, our analyses suggested different macro- and micro-environments in the reactor strongly affect the AOB community, allowing the development of different AOB species, such as N. europaea/eutropha and N. oligotropha groups, which improve the stability of nitritation process. A specific PCR primer set, used to target the 16S rRNA gene of anammox bacteria, confirmed the presence of the Ca. Brocadia fulgida type, able to grow in precence of organic matter and to tolerate high nitrite concentrations. The diversity of denitrifiers was assessed by using dissimilatory nitrite reductase (nirS gene-based analyses, who showed denitifiers were related to different betaproteobacterial genera, such as Thauera, Pseudomonas, Dechloromonas and Aromatoleum, able to assist in forming microbial aggregates. Concerning possible secondary processes, no n-damo bacteria were found while NOB from the genus of Nitrobacter

  11. Microbial community stratification in Membrane-Aerated Biofilm Reactors for Completely Autotrophic Nitrogen Removal

    DEFF Research Database (Denmark)

    Pellicer i Nàcher, Carles; Ruscalleda, Maël; Terada, Akihiko;

    bacterial granules or biofilms. In this sense, completely autotrophic nitrogen removal from high ammonium strength wastewater was achieved in a Membrane-Aereated Biofilm Reactor (MABR) in a single step. Here, a biofilm containing nitrifiers (Aerobic Ammonium and Nitrite Oxidizing Bacteria, AOB and NOB......Due to the necessity of a source of nitrite, most of the processes involving Anaerobic Ammonium Oxidation (Anammox) are based on a separated two-step process with a previous partial-nitritation reactor. However, these two processes can occur simultaneously in the same reactor by taking advantage of......, respectively) and Anaerobic Ammonium Oxidizing Bacteria (AnAOB) is grown on bubbleless aeration membranes to remove ammonium. Since oxygen permeates through the membrane-biofilm interface while ammonium diffuses into the biofilm from the biofilm-liquid interface, oxygen gradients can be established across the...

  12. Sequential Aeration of Membrane-Aerated Biofilm Reactors for High-Rate Autotrophic Nitrogen Removal: Experimental Demonstration

    DEFF Research Database (Denmark)

    Pellicer i Nàcher, Carles; Sun, Sheng-Peng; Lackner, Susanne;

    2010-01-01

    One-stage autotrophic nitrogen (N) removal, requiring the simultaneous activity of aerobic and anaerobic ammonium oxidizing bacteria (AOB and AnAOB), can be obtained in spatially redox-stratified biofilms. However, previous experience with Membrane-Aerated Biofilm Reactors (MABRs) has revealed a...... difficulty in reducing the abundance and activity of nitrite oxidizing bacteria (NOB), which drastically lowers process efficiency. Here we show how sequential aeration is an effective strategy to attain autotrophic N removal in MABRs: Two separate MABRs, which displayed limited or no N removal under......S rRNA gene confirmed that sequential aeration, even at elevated average O2 loads, stimulated the abundance of AnAOB and AOB and prevented the increase in NOB. Nitrous oxide (N2O) emissions were 100-fold lower compared to other anaerobic ammonium oxidation (Anammox)-nitritation systems. Hence, by...

  13. Gender comparisons in anaerobic power and anaerobic capacity tests.

    OpenAIRE

    Maud, P. J.; Shultz, B B

    1986-01-01

    The purpose of the study was to compare anaerobic power and anaerobic capacity test scores between young active men and women. Three performance measures of anaerobic power and two of anaerobic capacity were administered to a sample comprising 52 male and 50 female college students (means age = 21.4 yrs). Results indicated significant differences between men and women in body height, weight and per cent fat, in fat free mass (FFM), anaerobic power, and anaerobic capacity when recorded as gros...

  14. [Short or Long-Term Influence of Phenol on Nitrogen Removal Efficiency of ANAMMOX Sludge].

    Science.gov (United States)

    Yang, Peng-bing; Li, Xiang; Huang, Yong; Zhu, Liang; Cui, Jian-hong; Xu, Shan-shan

    2015-10-01

    The effects of phenol concentration on nitrogen removal efficiency in ANAMMOX sludge were studied in short or long-term. The nitrogen removal rate decreased rapidly with the increase of concentration of phenol in short-term. When the phenol concentration was above 600 mg x L(-1), the removal rate of NH4(+) -N was lower than 6% and the removal rate of TN was only about 10%. The long-term experimental results showed when the phenol concentration was below 100 mg x L(-1), the removal rate of NH4(+) -N can reach 99%, which indicated that ANAMMOX bacteria have a process of adaptation to the low concentration of phenol. However, when the phenol concentration was above 400 mg x L(-1), the removal rate of NH4(+) -N and TN was only 23.59% and 50.3%, the activity in sludge was significantly inhibited which was similarly to the short-term and the activity of denitrifying bacteria was significantly higher than ANAMMOX bacteria. As an organic carbon source, phenol can activated denitrification reaction and finally plays a dominant role in the system. However, the high concentration of phenol (1 000 mg x L(-1)) also has an inhibitory effect on denitrification bacteria. Half inhibitory concentration (IC50) of phenol to ANAMMOX activity was 71.57 mg x L(-1) by fitting. After 18 days' recovery, the stoichiometric ratios of nitrogen were changed, although the NH4(+) -N was basicly removed. The ratio of removed NH4(+) -N, reomved NO2(-) -N and produced NO3(-) -N was 1: 0.86: 0.2. Our results showed that the concentration of phenol should be controlled within a reasonable range, so that the reactor can achieve simultaneous removal of phenol and nitrogen. PMID:26841611

  15. Genome-based microbial ecology of anammox granules in a full-scale wastewater treatment system

    OpenAIRE

    Speth, D.R.; Zandt, M.H. in 't; Guerrero Cruz, S.; Dutilh, B.E.; Jetten, M. S. M.

    2016-01-01

    Partial-nitritation anammox (PNA) is a novel wastewater treatment procedure for energy-efficient ammonium removal. Here we use genome-resolved metagenomics to build a genome-based ecological model of the microbial community in a full-scale PNA reactor. Sludge from the bioreactor examined here is used to seed reactors in wastewater treatment plants around the world; however, the role of most of its microbial community in ammonium removal remains unknown. Our analysis yielded 23 near-complete d...

  16. Nitrogen Removal from Digested Black Water by One-stage Partial Nitritation and Anammox

    DEFF Research Database (Denmark)

    Vlaeminck, S.E.; Terada, Akihiko; Smets, Barth F.;

    2009-01-01

    rate of ca. 700 mg N L-1 d(-1) was reached over the subsequent 5 months. Suppression of the nitrite oxidizing bacteria at free ammonia levels above 3 mg N L-1 resulted in a nitrogen removal efficiency of 76%. The favorable ratios of both organic and inorganic carbon to nitrogen guaranteed endured......-stage partial nitritation and anammox, which will allow a significant decrease in operational costs compared to conventional nitrification/denitrification....

  17. Preliminary research on the anammox process and control of nitrogen compounds in a recirculating aquaculture system

    OpenAIRE

    Savin Cristian; Păsărin Benone; Patriche Neculai; Talpeş Marilena; Cristea Victor; Tenciu Magdalena

    2013-01-01

    Using anammox process in biological filtration of technological water within recirculatingaquaculture system is an alternative to nitrification / denitrification process which can reduce productioncosts, especially energy by replacing aerobic biological processes that require high oxygen consumption,provided through the addition for optimal function of biofilter (conversion of N-NH4 and N-NO2). Aim ofthis paper is to highlight the first steps in the control of nitrogen compounds in recirculat...

  18. Perspectives for anaerobic digestion

    DEFF Research Database (Denmark)

    Ahring, Birgitte Kiær

    2003-01-01

    to the soil. Anaerobic digestion (AD) is one way of achieving this goal and it will furthermore, reduce energy consumption or may even be net energy producing. This chapter aims at provide a basic understanding of the world in which anaerobic digestion is operating today. The newest process developments...

  19. Anaerobic sludge granulation

    NARCIS (Netherlands)

    Hulshoff Pol, L.W.; Castro Lopes, de S.I.; Lettinga, G.; Lens, P.N.L.

    2004-01-01

    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades
    This paper reviews different theories on anaerobic sludge granulation in UASB-reactors that have been proposed during the past two decades. The initial stage

  20. Oxygen at nanomolar levels reversibly suppresses process rates and gene expression in anammox and denitrification in the oxygen minimum zone off Northern Chil

    DEFF Research Database (Denmark)

    Dalsgaard, Tage; Stewart, Frank J.; Thamdrup, Bo;

    2014-01-01

    at nanomolar levels affects anammox and denitrification rates and the transcription of nitrogen cycle genes in the anoxic OMZ off Chile. Rates of anammox and denitrification were reversibly suppressed, most likely at the enzyme level. Fiftypercent inhibition of N2 and N2O production by...

  1. Model-based evaluation of the role of Anammox on nitric oxide and nitrous oxide productions in membrane aerated biofilm reactor

    DEFF Research Database (Denmark)

    Ni, Bing-Jie; Smets, Barth F.; Yuan, Zhiguo;

    2013-01-01

    A multispecies one-dimensional biofilm model considering nitric oxide (NO) and nitrous oxide (N2O) productions for membrane aerated biofilm reactor (MABR) that remove nitrogen autotrophically through aerobic ammonia oxidation followed by Anammox is used to study the role of Anammox activity on th...

  2. Heterotrophic denitrification vs. autotrophic anammox – quantifying collateral effects on the oceanic carbon cycle

    Directory of Open Access Journals (Sweden)

    W. Koeve

    2010-08-01

    Full Text Available The conversion of fixed nitrogen to N2 in suboxic waters is estimated to contribute roughly a third to total oceanic losses of fixed nitrogen and is hence understood to be of major importance to global oceanic production and, therefore, to the role of the ocean as a sink of atmospheric CO2. At present heterotrophic denitrification and autotrophic anammox are considered the dominant sinks of fixed nitrogen. Recently, it has been suggested that the trophic nature of pelagic N2-production may have additional, "collateral" effects on the carbon cycle, where heterotrophic denitrification provides a shallow source of CO2 and autotrophic anammox a shallow sink. Here, we analyse the stoichiometries of nitrogen and associated carbon conversions in marine oxygen minimum zones (OMZ focusing on heterotrophic denitrification, autotrophic anammox, and dissimilatory nitrate reduction to nitrite and ammonium in order to test this hypothesis quantitatively. For open ocean OMZs the combined effects of these processes turn out to be clearly heterotrophic, even with high shares of the autotrophic anammox reaction in total N2-production and including various combinations of dissimilatory processes which provide the substrates to anammox. In such systems, the degree of heterotrophy (ΔCO2:ΔN2, varying between 1.7 and 6.5, is a function of the efficiency of nitrogen conversion. On the contrary, in systems like the Black Sea, where suboxic N-conversions are supported by diffusive fluxes of NH4+ originating from neighbouring waters with sulphate reduction, much lower values of ΔCO2:ΔN2 can be found. However, accounting for concomitant diffusive fluxes of CO2, the ratio approaches higher values similar to those computed for open ocean OMZs. Based on this analysis, we question the significance of collateral effects concerning the trophic

  3. Long-term performance and microbial community characterization of an osmotic anammox system for removing reverse-fluxed ammonium.

    Science.gov (United States)

    Li, Xiaojin; Sun, Shan; Badgley, Brian D; He, Zhen

    2016-07-01

    A novel osmotic anammox (OsAMX) system coupling nitritation-anammox with forward osmosis (FO) has been developed for removal of reverse-fluxed ammonium when using NH4HCO3 as a draw solute. In this study, long-term performance and microbial community structure were investigated. The nitritation-anammox reactor maintained an ammonium concentration of 7.0±5.0mgNL(-1) (DO=0.9±0.2mgO2L(-1)), while the FO achieved a water flux of 2.3±0.4LMH (0.5M NH4HCO3 draw). The low water flux was obtained likely due to concentration polarization, reverse salt flux (RSF) and membrane fouling. Sequencing analyses reveled that Candidatus Jettenia was the dominant anammox genus, while Candidatus Brocadia was most abundant in biofilm. The shift of anammox bacterial population indicated possible higher tolerance of Ca. Brocadia for DO or elevated RSF. These results encourage further investigation of OsAMX system optimization, membrane fouling migration strategies, and application with actual wastewater. PMID:27046789

  4. [Simultaneous Biotransformation of Ammonium and Nitrate via Zero-Valent Iron on Anaerobic Conditions].

    Science.gov (United States)

    Zhou, Jian; Huang, Yong; Yuan, Yi; Liu, Xin; Li, Xiang; Shen, Jie; Yang, Peng-bing

    2015-12-01

    Zero-valent iron (ZVI) was used to improve the biological autotrophic denitrification process between nitrate and ammonia by anaerobic ammonia oxidation ( ANAMMOX) bacteria. With the addition of ZVI, the biological autotrophic denitrification process could be reacted in the influent condition of pH was 7-8, at 35°C ±0.5°C, the concentration of ammonia was 50-100 mg · L⁻¹ and the concentration of nitrate was 50-100 mg · L⁻¹. The highest conversion rate could be reached to 17.2 mg · (L·h) ⁻¹. With the change of reaction time and the molar ratio of nitrate and ammonia in influent, the final molar conversion ratio of nitrate and ammonia in effluent fluctuated between 1.2-3. 5. The result showed that this autotrophic denitrification process was not belonged to elementary reaction. The mechanism of this autotrophic denitrification process could be summarized that with the reduction of ZVI, the nitrate could be reduced to nitrite. Hereafter, the ANAMMOX process reacted between the nitrite and ammonia. PMID:27011992

  5. Anaerobic Digestion and its Applications

    Science.gov (United States)

    Anaerobic digestion is a natural biological process. The initials "AD" may refer to the process of anaerobic digestion, or the built systems of anaerobic digesters. While there are many kinds of digesters, the biology is basically the same for all. Anaerobic digesters are built...

  6. A microdiversity study of anammox bacteria reveals a novel Candidatus Scalindua phylotype in marine oxygen minimum zones

    Digital Repository Service at National Institute of Oceanography (India)

    Woebken, D.; Lam, P.; Kuypers, M.M.M.; Naqvi, S.W.A.; Kartal, B.; Strous, M.; Jetten, M.S.M.; Fuchs, B.M.; Amann, R.

    to the subspecies level (Gürtler and Stanisich, 1996; Normand et al., 1996). Results Phylogenetic analysis based on 16S rRNA gene sequences From the five clone libraries constructed with the planctomycete-specific primer Pla46F and the universal primer1037R,1384... affiliated to the Candidatus genera of anammox bacteria and were further analysed. Sequences related to known anammox bacteria. 16S rRNA gene-ITS clone libraries of the three OMZs and the Black Sea suboxic water column constructed with primer Pla46F and 1037R...

  7. Isotopic evidence for nitrous oxide production pathways in a partial nitritation-anammox reactor.

    Science.gov (United States)

    Harris, Eliza; Joss, Adriano; Emmenegger, Lukas; Kipf, Marco; Wolf, Benjamin; Mohn, Joachim; Wunderlin, Pascal

    2015-10-15

    Nitrous oxide (N2O) production pathways in a single stage, continuously fed partial nitritation-anammox reactor were investigated using online isotopic analysis of offgas N2O with quantum cascade laser absorption spectroscopy (QCLAS). N2O emissions increased when reactor operating conditions were not optimal, for example, high dissolved oxygen concentration. SP measurements indicated that the increase in N2O was due to enhanced nitrifier denitrification, generally related to nitrite build-up in the reactor. The results of this study confirm that process control via online N2O monitoring is an ideal method to detect imbalances in reactor operation and regulate aeration, to ensure optimal reactor conditions and minimise N2O emissions. Under normal operating conditions, the N2O isotopic site preference (SP) was much higher than expected - up to 40‰ - which could not be explained within the current understanding of N2O production pathways. Various targeted experiments were conducted to investigate the characteristics of N2O formation in the reactor. The high SP measurements during both normal operating and experimental conditions could potentially be explained by a number of hypotheses: i) unexpectedly strong heterotrophic N2O reduction, ii) unknown inorganic or anammox-associated N2O production pathway, iii) previous underestimation of SP fractionation during N2O production from NH2OH, or strong variations in SP from this pathway depending on reactor conditions. The second hypothesis - an unknown or incompletely characterised production pathway - was most consistent with results, however the other possibilities cannot be discounted. Further experiments are needed to distinguish between these hypotheses and fully resolve N2O production pathways in PN-anammox systems. PMID:26164660

  8. Biodegradation and chemical precipitation of dissolved nutrients in anaerobically digested sludge dewatering centrate.

    Science.gov (United States)

    Galvagno, G; Eskicioglu, C; Abel-Denee, M

    2016-06-01

    The objective of this research was to assess specific side-stream treatment processes for biodegradation and precipitation of dissolved nutrients in dewatering centrate. In this study, characterization was made of a conventional suspended growth deammonification treatment process for transforming dissolved polyphosphate (poly-P), dissolved organic phosphorus (DOP) and dissolved organic nitrogen (DON) in two types of dewatering centrate. The deammonification process was configured as a sequencing batch reactor (SBR), combining partial nitrification and anaerobic ammonia oxidation (anammox) in a single tank. The first centrate feed studied was from the full-scale Annacis Island wastewater treatment plant (AIWWTP) located in Metro Vancouver, Canada. The second centrate feed was from a lab-scale anaerobic digester (AD) fed waste sludge from the existing City of Kelowna Wastewater Treatment Facility (KWTF), located in the Okanagan Valley, Canada. In addition, poly aluminum chloride (PACL) dosing was assessed for final polishing of dissolved nutrients. The deammonification SBR (DeSBR) process showed similar treatment characteristics for both the KWTF and AIWWTP centrates with excellent DON removal and poor non-reactive dissolved phosphorus (NRDP) removal. A statistical comparison of the DOP and poly-P through the DeSBR process suggests that DOP has a higher biodegradation potential. Future research focused on understanding the variables associated with degradation of DOP could lead to better NRDP removal through deammonification processes. Utilization of a post-anammox PACL chemical dosing stage can achieve the objective of precipitating any residual DON and NRDP and producing an effluent that has lower dissolved nutrients than the pre-digestion KWTF dewatering centrate scenario. PMID:27023924

  9. Denitrification, anammox and fixed nitrogen removal in the water column of a tropical great lake

    Science.gov (United States)

    Darchambeau, François; Roland, Fleur; Crowe, Sean A.; De Brabandere, Loreto; Llirós, Marc; Garcia-Armisen, Tamara; Inceoglu, Ozgul; Michiels, Céline; Servais, Pierre; Morana, Cédric D. T.; Bouillon, Steven; Meysman, Filip; Veuger, Bart; Masilya, Pascal M.; Descy, Jean-Pierre; Borges, Alberto V.

    2013-04-01

    If rates of microbial denitrification in aquatic systems are poorly constrained, it is much more the case for tropical water bodies. Lake Kivu [2.50° S 1.59° S, 29.37° E 28.83° E] is one of the great lakes of the East African Rift. It is an oligotrophic lake characterized by anoxic deep waters rich in dissolved gases (methane and carbon dioxide) and nutrients, and by well oxygenated and nutrient-depleted surface waters. During the seasonally stratified rainy season (October to May), a nitrogenous zone characterized by the accumulation of nitrite (NO2-) and nitrate (NO3-) is often observed in the lower layer of the mixolimnion. It results from nitrification of ammonium released by decaying organic matter. With the seasonal uplift of the oxygen minimum zone, the nitrogenous zone becomes anoxic and might be the most preferential area for fixed nitrogen (N) removal in Lake Kivu. Our work aimed at identifying and quantifying the processes of N losses by denitrification and/or anammox in the nitrogenous zone of the Lake Kivu water column. During 5 sampling campaigns (March 2010, October 2010, June 2011, February 2012 and September 2012), isotopic labelling experiments were used to quantify denitrification and anammox rates along vertical profiles at two pelagic stations of the main lake. Moreover, N2:Ar ratios were estimated during the September 2012 campaign, and 16S rDNA pyrosequencing was used to describe bacterial community composition during the last 2 campaigns. No bacteria related to organisms performing anammox was observed and labelling experiments failed to detect anammox at any locations and any depths. In Lake Kivu, denitrifying bacteria were mainly related to Denitratisoma and Thiobacillus genus. Significant denitrification rates were observed at several occasions, especially under the oxic-anoxic interface in the bottom of the nitracline. The annual average denitrification rate was estimated at ~150 μmoles N m-2 d-1. Denitrification was not the only

  10. Diversity of total and functional microbiome of anammox reactors fed with complex and synthetic nitrogen-rich wastewaters

    DEFF Research Database (Denmark)

    Gülay, Arda; Pellicer i Nàcher, Carles; Mutlu, Ayten Gizem;

    There are few comparitive studies of microbial structure, composition and phylogenetic diversity of the anammox reactors as a function of substrate complexity exist, representing a large gap in the scientific literature. In this study, we applied 16S rRNA gene (rDNA) tag-based 454 pyrosequencing ...

  11. Selection of controlled variables in bioprocesses. Application to a SHARON-Anammox process for autotrophic nitrogen removal

    DEFF Research Database (Denmark)

    Mauricio Iglesias, Miguel; Valverde Perez, Borja; Sin, Gürkan

    Selecting the right controlled variables in a bioprocess is challenging since the objectives of the process (yields, product or substrate concentration) are difficult to relate with a given actuator. We apply here process control tools that can be used to assist in the selection of controlled...... variables to the case of the SHARON-Anammox process for autotrophic nitrogen removal....

  12. Comparative genomics of two independently enriched ‘Candidatus Kuenenia stuttgartiensis’ anammox bacteria

    Directory of Open Access Journals (Sweden)

    DaanRSpeth

    2012-08-01

    Here we present a comparative genomic analysis of two ‘Ca. K. stuttgartiensis’ anammox bacteria that were independently enriched, with the aim to understand more about the evolution, cell plan and metabolism of these important microbes and to further improve and complete the reference genome. The two anammox bacteria used are ‘Ca. K. stuttgartiensis’ RU1, which was originally sequenced for the reference genome in 2002, and for the present study resequenced after seven (2002-2009 years in continuous culture. Furthermore ‘Ca. K. stuttgartiensis’ CH1, enriched from a Chinese wastewater treatment plant was used as an independent source of genomic information. The two different ‘Ca. Kuenenia’ bacteria showed a very high sequence identity (> 99 % at nucleotide level over the entire genome, but 31 genomic regions (average size 11 kb were absent from strain CH1 and 220 kb of sequence was specifically found in the CH1 assembly. The high sequence homology between these two bacteria indicates that mobile genetic elements are the main source of variation between these geographically widely separated strains.

  13. A new approach to simultaneous ammonium and dissolved methane removal from anaerobic digestion liquor: A model-based investigation of feasibility.

    Science.gov (United States)

    Chen, Xueming; Guo, Jianhua; Xie, Guo-Jun; Liu, Yiwen; Yuan, Zhiguo; Ni, Bing-Jie

    2015-11-15

    The presence of a high level of dissolved methane (e.g., 20-26 g m(-3)) in the anaerobic sludge digestion liquor represents a major challenge to the treatment of this stream, as its emission to the atmosphere contributes significantly to the carbon footprint of wastewater treatment. Here we propose a new approach to simultaneous ammonium and dissolved methane removal from the anaerobic digestion liquor through integrating partial nitritation-Anammox and denitrifying anaerobic methane oxidation (DAMO) processes in a single-stage membrane biofilm reactor (MBfR). In such an MBfR, the anaerobic digestion liquor is provided in the bulk liquid, while oxygen is supplied through gas-permeable membranes to avoid dissolved methane stripping. A previously developed model with appropriate extensions was applied to assess the system performance under different operational conditions and the corresponding microbial interactions. Both influent surface loading (or hydraulic retention time) and oxygen surface loading are found to significantly influence the total nitrogen (TN) and dissolved methane removal, which jointly determine the overall system performance. The counter diffusion and concentration gradients of substrates cause microbial stratification in the biofilm, where ammonia-oxidizing bacteria (AOB) attach close to the membrane surface (biofilm base) where oxygen and ammonium are available, while Anammox and DAMO microorganisms jointly grow in the biofilm layer close to the bulk liquid where methane, ammonium, and nitrite are available with the latter produced by AOB. These results provide first insights and useful information for the design and operation of this new technology for simultaneous ammonium and dissolved methane removal in its potential future applications. PMID:26342913

  14. Modeling of Nitrous Oxide Production from Nitritation Reactors Treating Real Anaerobic Digestion Liquor.

    Science.gov (United States)

    Wang, Qilin; Ni, Bing-Jie; Lemaire, Romain; Hao, Xiaodi; Yuan, Zhiguo

    2016-01-01

    In this work, a mathematical model including both ammonium oxidizing bacteria (AOB) and heterotrophic bacteria (HB) is constructed to predict N2O production from the nitritation systems receiving the real anaerobic digestion liquor. This is for the first time that N2O production from such systems was modeled considering both AOB and HB. The model was calibrated and validated using experimental data from both lab- and pilot-scale nitritation reactors. The model predictions matched the dynamic N2O, ammonium, nitrite and chemical oxygen demand data well, supporting the capability of the model. Modeling results indicated that HB are the dominant contributor to N2O production in the above systems with the dissolved oxygen (DO) concentration of 0.5-1.0 mg O2/L, accounting for approximately 75% of N2O production. The modeling results also suggested that the contribution of HB to N2O production decreased with the increasing DO concentrations, from 75% at DO = 0.5 mg O2/L to 25% at DO = 7.0 mg O2/L, with a corresponding increase of the AOB contribution (from 25% to 75%). Similar to HB, the total N2O production rate also decreased dramatically from 0.65 to 0.25 mg N/L/h when DO concentration increased from 0.5 to 7.0 mg O2/L. PMID:27125491

  15. Modeling of Nitrous Oxide Production from Nitritation Reactors Treating Real Anaerobic Digestion Liquor

    Science.gov (United States)

    Wang, Qilin; Ni, Bing-Jie; Lemaire, Romain; Hao, Xiaodi; Yuan, Zhiguo

    2016-01-01

    In this work, a mathematical model including both ammonium oxidizing bacteria (AOB) and heterotrophic bacteria (HB) is constructed to predict N2O production from the nitritation systems receiving the real anaerobic digestion liquor. This is for the first time that N2O production from such systems was modeled considering both AOB and HB. The model was calibrated and validated using experimental data from both lab- and pilot-scale nitritation reactors. The model predictions matched the dynamic N2O, ammonium, nitrite and chemical oxygen demand data well, supporting the capability of the model. Modeling results indicated that HB are the dominant contributor to N2O production in the above systems with the dissolved oxygen (DO) concentration of 0.5–1.0 mg O2/L, accounting for approximately 75% of N2O production. The modeling results also suggested that the contribution of HB to N2O production decreased with the increasing DO concentrations, from 75% at DO = 0.5 mg O2/L to 25% at DO = 7.0 mg O2/L, with a corresponding increase of the AOB contribution (from 25% to 75%). Similar to HB, the total N2O production rate also decreased dramatically from 0.65 to 0.25 mg N/L/h when DO concentration increased from 0.5 to 7.0 mg O2/L. PMID:27125491

  16. Anaerobic biotransformation of estrogens

    Energy Technology Data Exchange (ETDEWEB)

    Czajka, Cynthia P. [Department of Microbiology, University of Manitoba, Winnipeg, MB, R3T 2N2 (Canada); Londry, Kathleen L. [Department of Microbiology, University of Manitoba, Winnipeg, MB, R3T 2N2 (Canada)]. E-mail: londryk@cc.umanitoba.ca

    2006-08-31

    Estrogens are important environmental contaminants that disrupt endocrine systems and feminize male fish. We investigated the potential for anaerobic biodegradation of the estrogens 17-{alpha}-ethynylestradiol (EE2) and 17-{beta}-estradiol (E2) in order to understand their fate in aquatic and terrestrial environments. Cultures were established using lake water and sediment under methanogenic, sulfate-, iron-, and nitrate-reducing conditions. Anaerobic degradation of EE2 (added at 5 mg/L) was not observed in multiple trials over long incubation periods (over three years). E2 (added at 5 mg/L) was transformed to estrone (E1) under all four anaerobic conditions (99-176 {mu}g L{sup -1} day{sup -1}), but the extent of conversion was different for each electron acceptor. The oxidation of E2 to E1 was not inhibited by E1. Under some conditions, reversible inter-conversion of E2 and E1 was observed, and the final steady state concentration of E2 depended on the electron-accepting condition but was independent of the total amount of estrogens added. In addition, racemization occurred and E1 was also transformed to 17-{alpha}-estradiol under all but nitrate-reducing conditions. Although E2 could be readily transformed to E1 and in many cases 17-{alpha}-estradiol under anaerobic conditions, the complete degradation of estrogens under these conditions was minimal, suggesting that they would accumulate in anoxic environments.

  17. The anaerobic digestion process

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, C.J. [National Renewable Energy Lab., Golden, CO (United States); Boone, D.R. [Oregon Graduate Inst., Portland, OR (United States)

    1996-01-01

    The microbial process of converting organic matter into methane and carbon dioxide is so complex that anaerobic digesters have long been treated as {open_quotes}black boxes.{close_quotes} Research into this process during the past few decades has gradually unraveled this complexity, but many questions remain. The major biochemical reactions for forming methane by methanogens are largely understood, and evolutionary studies indicate that these microbes are as different from bacteria as they are from plants and animals. In anaerobic digesters, methanogens are at the terminus of a metabolic web, in which the reactions of myriads of other microbes produce a very limited range of compounds - mainly acetate, hydrogen, and formate - on which the methanogens grow and from which they form methane. {open_quotes}Interspecies hydrogen-transfer{close_quotes} and {open_quotes}interspecies formate-transfer{close_quotes} are major mechanisms by which methanogens obtain their substrates and by which volatile fatty acids are degraded. Present understanding of these reactions and other complex interactions among the bacteria involved in anaerobic digestion is only now to the point where anaerobic digesters need no longer be treated as black boxes.

  18. Anaerobic biological treatment

    International Nuclear Information System (INIS)

    The Enso-Fenox process has been very successfully used to remove chlorinated phenolic compounds from pulp bleaching effluents. It is a two-stage anaerobic/aerobic process consisting of a nonmethanogenic anaerobic fluidized bed followed by a trickling filter. Studies have been conducted on reductive dechlorination of chlorinated aromatic compounds under anaerobic conditions with chlorinated phenols as the sole carbon and energy source. Approximately 40% of the added chlorophenols was converted to CH4 and CO2. Substrate loading rates were 20 mg/L/d at hydraulic detention times of 2-4 days with 90% substrate conversion efficiency. Reductive dechlorination of mono, di-, tri-, and pentachlorophenols has been demonstrated in anaerobic sewage sludge. The following constituents were tested in the laboratory at their approximate concentrations in coal conversion wastewater (CCWW) and were anaerobically degraded in serum bottles: 1,000 mg/L phenol; 500 mg/L resorcinol; 1,000 mg/L benzoic acid; 500 mg/L p-cresol; 200 mg/L pyridine; 2,000 mg/L benzoic acid; 250 mg/L 40 methylcatechol; 500 mg/L 4-ethylpyridine; and 2,000 mg/L hexanoic acid. A petrochemical may initially exhibit toxicity to an unacclimated population of methane-fermenting bacteria, but with acclimation the toxicity may be greatly reduced or disappear. In addition, the microorganisms may develop the capacity to actually degrade compounds which showed initial toxicity. Since biomass digestion requires a complete consortium of bacteria, it is relevant to study the effect of a given process as well as to individual steps within the process. A toxicant can inhibit the rate-limiting step and/or change the step that is rate-limiting. Both manifestations of toxicity can severely affect the overall process

  19. Systematic design of an optimal control system for the SHARON-Anammox process

    DEFF Research Database (Denmark)

    Valverde Perez, Borja; Mauricio Iglesias, Miguel; Sin, Gürkan

    2016-01-01

    found to be dissolved oxygen (DO) and pH in the SHARON reactor. Furthermore, to relate the controller actions to process operation objective, nitrogen removal efficiency, two cascade control systems are designed. The first cascade loop controls TNN/TAN ratio in the influent to the Anammox reactor by...... (CVs). The best candidates to CVs were paired with the manipulated variables using the relative gain array. The proposed control structure was further analyzed and verified for disturbance rejection using the CLDG plots. The optimal pairing of CVs with the actuators (kLa and acid/base addition) is...... adjusting the set point for DO in the regulatory layer, while the second cascade loop controls the nitrogen removal efficiency (i.e. effluent TNN and TAN) by adjusting the TNN/TAN ratio at the effluent of the SHARON reactor. The control system is evaluated and benchmarked using a set of realistic dynamic...

  20. Plant-wide (BSM2) evaluation of reject water treatment with a SHARON-Anammox process

    DEFF Research Database (Denmark)

    Volcke, Eveline; Gernaey, Krist; Vrecko, Darko;

    2006-01-01

    In wastewater treatment plants (WWTPs) equipped with sludge digestion and dewatering systems, the reject water originating from these facilities contributes significantly to the nitrogen load of the activated sludge tanks, to which it is typically recycled. In this paper, the impact of reject water...... streams on the performance of a WWTP is assessed in a simulation study, using the Benchmark Simulation Model no. 2 (BSM2), that includes the processes describing sludge treatment and in this way allows for plant-wide evaluation. Comparison of performance of a WWTP without reject water with a WWTP where...... treatment plant, reject water treatment with a combined SHARON-Anammox process seems a promising option. The simulation results indicate that significant improvements of the effluent quality of the main wastewater treatment plant can be realized. An economic evaluation of the different scenarios is...

  1. Anaerobic azo dye reduction

    OpenAIRE

    Zee, van der, KG Kristoffer

    2002-01-01

    Azo dyes, aromatic moieties linked together by azo (-N=N-) chromophores, represent the largest class of dyes used in textile-processing and other industries. The release of these compounds into the environment is undesirable, not only because of their colour, but also because many azo dyes and their breakdown products are toxic and/or mutagenic to life. To remove azo dyes from wastewater, a biological treatment strategy based on anaerobic reduction of the azo dyes, followed by aerobic transfo...

  2. New perspectives in anaerobic digestion

    DEFF Research Database (Denmark)

    van Lier, J.B.; Tilche, A.; Ahring, Birgitte Kiær;

    2001-01-01

    requirements. In fact, most advances were achieved during the last three decades, when high-rate reactor systems were developed and a profound insight was obtained in the microbiology of the anaerobic communities. This insight led to a better understanding of anaerobic treatment and, subsequently, to a broader......The IWA specialised group on anaerobic digestion (AD) is one of the oldest working groups of the former IAWQ organisation. Despite the fact that anaerobic technology dates back more than 100 years, the technology is still under development, adapting novel treatment systems to the modern...

  3. Anaerobic wastewater treatment using anaerobic baffled bioreactor: a review

    Science.gov (United States)

    Hassan, Siti; Dahlan, Irvan

    2013-09-01

    Anaerobic wastewater treatment is receiving renewed interest because it offers a means to treat wastewater with lower energy investment. Because the microorganisms involved grow more slowly, such systems require clever design so that the microbes have sufficient time with the substrate to complete treatment without requiring enormous reactor volumes. The anaerobic baffled reactor has inherent advantages over single compartment reactors due to its circulation pattern that approaches a plug flow reactor. The physical configuration of the anaerobic baffled reactor enables significant modifications to be made; resulting in a reactor which is proficient of treating complex wastewaters which presently require only one unit, ultimately significant reducing capital costs. This paper also concerns about mechanism, kinetic and hydrodynamic studies of anaerobic digestion for future application of the anaerobic baffled reactor for wastewater treatment.

  4. A combined upflow anaerobic sludge bed, aerobic, and anoxic fixed-bed reactor system for removing tetramethylammonium hydroxide and nitrogen from light-emitting diode wastewater.

    Science.gov (United States)

    Lin, Han-Lin; Chen, Sheng-Kun; Huang, Yu-Wen; Chen, Wei-Cheng; Chien, Wei-Cheng; Cheng, Sheng-Shung

    2016-06-01

    A laboratory study using a combined upflow anaerobic sludge bed (UASB) and aerobic and anoxic fixed-bed reactor system was undertaken to explore its capability for removing tetramethylammonium hydroxide (TMAH) and nitrogen from light-emitting diode wastewater. When the organic loading rate was maintained at 0.26-0.65 kg TMAH m(-3 )d(-1), the UASB reactor removed 70-100% of TMAH through methanogenesis. When the [Formula: see text] -N loading rate was maintained at 0.73-1.4 kg [Formula: see text]-N m(-3 )d(-1), the aerobic reactor oxidized 31-59% of [Formula: see text]-N to [Formula: see text]-N through nitritation. When the nitrogen loading rate was maintained at 0.42-0.75 kg N m(-3 )d(-1), the anoxic reactor removed 27-63% of nitrogen through anammox. The performance data of the combined reactor system agreed well with the stoichiometric relationships of methanogenesis, nitritation, and anammox. The batch studies showed that a higher initial TMAH concentration of up to 2520 mg L(-1) gave a higher methanogenic activity of up to 16 mL CH4 g(-1) VSS d(-1). An increase in the initial TMAH concentration of up to 500 mg L(-1) gradually decreased the activity of ammonia-oxidizing bacteria; whereas an increase in the initial TMAH concentration of up to 47 mg L(-1) imposed a marked inhibiting effect on the activity of anammox bacteria. PMID:26583577

  5. Techniques for anaerobic susceptibility testing.

    Science.gov (United States)

    Thornsberry, C

    1977-03-01

    Minimal inhibitory concentrations (MICs) of antimicrobial agents for anaerobic bacteria can be determined by agar dilution and broth dilution (including microdilution) techniques. If MICs are not determined routinely, the disk broth or category methods are recommended for routine use. The Bauer-Kirby disk diffusion method and its interpretative standards should not be used for anaerobes. PMID:850089

  6. Anaerobic Digestion of Piggery Waste

    NARCIS (Netherlands)

    Velsen, van A.F.M.

    1981-01-01

    Anaerobic digestion is a biological process by which organic matter is converted to methane and carbon dioxide by microbes in the absence of air (oxygen). In nature, anaerobic conversions occur at all places where organic material accumulates and the supply of oxygen is deficient, e.g. in marshes an

  7. Economic viability of anaerobic digestion

    Energy Technology Data Exchange (ETDEWEB)

    Wellinger, A. [INFOENERGIE, Ettenhausen (Switzerland)

    1996-01-01

    The industrial application of anaerobic digestion is a relatively new, yet proven waste treatment technology. Anaerobic digestion reduces and upgrades organic waste, and is a good way to control air pollution as it reduces methane and nitrous gas emissions. For environmental and energy considerations, anaerobic digestion is a nearly perfect waste treatment process. However, its economic viability is still in question. A number of parameters - type of waste (solid or liquid), digester system, facility size, product quality and end use, environmental requirements, cost of alternative treatments (including labor), and interest rates - define the investment and operating costs of an anaerobic digestion facility. Therefore, identical facilities that treat the same amount and type of waste may, depending on location, legislation, and end product characteristics, reveal radically different costs. A good approach for evaluating the economics of anaerobic digestion is to compare it to treatment techniques such as aeration or conventional sewage treatment (for industrial wastewater), or composting and incineration (for solid organic waste). For example, the cost (per ton of waste) of in-vessel composting with biofilters is somewhat higher than that of anaerobic digestion, but the investment costs 1 1/2 to 2 times more than either composting or anaerobic digestion. Two distinct advantages of anaerobic digestion are: (1) it requires less land than either composting or incinerating, which translates into lower costs and milder environmental and community impacts (especially in densely populated areas); and (2) it produces net energy, which can be used to operate the facility or sold to nearby industries.

  8. Anaerobic fungal populations

    International Nuclear Information System (INIS)

    The development of molecular techniques has greatly broadened our view of microbial diversity and enabled a more complete detection and description of microbial communities. The application of these techniques provides a simple means of following community changes, for example, Ishii et al. described transient and more stable inhabitants in another dynamic microbial system, compost. Our present knowledge of anaerobic gut fungal population diversity within the gastrointestinal tract is based upon isolation, cultivation and observations in vivo. It is likely that there are many species yet to be described, some of which may be non-culturable. We have observed a distinct difference in the ease of cultivation between the different genera, for example, Caecomyes isolates are especially difficult to isolate and maintain in vitro, a feature that is likely to result in the under representation of this genera in culture-based enumerations. The anaerobic gut fungi are the only known obligately anaerobic fungi. For the majority of their life cycles, they are found tightly associated with solid digesta in the rumen and/or hindgut. They produce potent fibrolytic enzymes and grow invasively on and into the plant material they are digesting making them important contributors to fibre digestion. This close association with intestinal digesta has made it difficult to accurately determine the amount of fungal biomass present in the rumen, with Orpin suggesting 8% contribution to the total microbial biomass, whereas Rezaeian et al. more recently gave a value of approximately 20%. It is clear that the rumen microbial complement is affected by dietary changes, and that the fungi are more important in digestion in the rumens of animals fed with high-fibre diets. It seems likely that the gut fungi play an important role within the rumen as primary colonizers of plant fibre, and so we are particularly interested in being able to measure the appearance and diversity of fungi on the plant

  9. Microbial structures and community functions of anaerobic sludge in six full-scale wastewater treatment plants as revealed by 454 high-throughput pyrosequencing.

    Science.gov (United States)

    Shu, Duntao; He, Yanling; Yue, Hong; Wang, Qingyi

    2015-06-01

    The microbial communities and abundance in anaerobic sludge from 4 industrial and 2 municipal wastewater treatment plants were investigated using 454 pyrosequencing technology in this study. A total of 5482-8692 high-quality reads of 16S rRNA V3-V5 regions were obtained. Taxonomic analysis using QIIME and RDP classifier found that Proteobacteria, Bacteroidetes, Chloroflexi and Firmicutes were the most abundant phyla in these samples. Furthermore, real-time PCR was used to validate the absolute abundance of these 16S rRNAs and some functional genes, including total bacteria, anammox bacteria, NOB (Nitrobacter, Nitrospira), AOA amoA, AOB amoA, nosZ, nirS, nirK, narG, napA, nrfA, mcrA and dsrA. Multivariate linear regression analysis indicated that AOA might be mixotrophic. Finally, redundancy analysis was used to reveal the relationships between operation parameters and microbial communities. Results showed that the coexistence of anammox, denitrification and DNRA could be useful for the simultaneous removal of nitrogen and organic matter. PMID:25817026

  10. Thermal stability of ladderane lipids as determined by hydrous pyrolysis

    Science.gov (United States)

    Jaeschke, A.; Lewan, M.D.; Hopmans, E.C.; Schouten, S.; Sinninghe, Damste J.S.

    2008-01-01

    Anaerobic ammonium oxidation (anammox) has been recognized as a major process resulting in loss of fixed inorganic nitrogen in the marine environment. Ladderane lipids, membrane lipids unique to anammox bacteria, have been used as markers for the detection of anammox in marine settings. However, the fate of ladderane lipids after sediment burial and maturation is unknown. In this study, anammox bacterial cell material was artificially matured by hydrous pyrolysis at constant temperatures ranging from 120 to 365 ??C for 72 h to study the stability of ladderane lipids during progressive dia- and catagenesis. HPLC-MS/MS analysis revealed that structural alterations of ladderane lipids already occurred at 120 ??C. At temperatures >140 ??C, ladderane lipids were absent and only more thermally stable products could be detected, i.e., ladderane derivatives in which some of the cyclobutane rings were opened. These diagenetic products of ladderane lipids were still detectable up to temperatures of 260 ??C using GC-MS. Thus, ladderane lipids are unlikely to occur in ancient sediments and sedimentary rocks, but specific diagenetic products of ladderane lipids will likely be present in sediments and sedimentary rocks of relatively low maturity (i.e., C31 hopane 22S/(22S + 22R) ratio 0.5). ?? 2008 Elsevier Ltd.

  11. Parotitis due to anaerobic bacteria.

    Science.gov (United States)

    Matlow, A; Korentager, R; Keystone, E; Bohnen, J

    1988-01-01

    Although Staphylococcus aureus remains the pathogen most commonly implicated in acute suppurative parotitis, the pathogenic role of gram-negative facultative anaerobic bacteria and strict anaerobic organisms in this disease is becoming increasingly recognized. This report describes a case of parotitis due to Bacteroides disiens in an elderly woman with Sjögren's syndrome. Literature reports on seven additional cases of suppurative parotitis due to anaerobic bacteria are reviewed. Initial therapy of acute suppurative parotitis should include coverage for S. aureus and, in a very ill patient, coverage of gram-negative facultative organisms with antibiotics such as cloxacillin and an aminoglycoside. A failure to respond clinically to such a regimen or isolation of anaerobic bacteria should lead to the consideration of the addition of clindamycin or penicillin. PMID:3287567

  12. Aerobic Microbial Respiration In Oceanic Oxygen Minimum Zones.

    Directory of Open Access Journals (Sweden)

    Tim Kalvelage

    Full Text Available Oxygen minimum zones are major sites of fixed nitrogen loss in the ocean. Recent studies have highlighted the importance of anaerobic ammonium oxidation, anammox, in pelagic nitrogen removal. Sources of ammonium for the anammox reaction, however, remain controversial, as heterotrophic denitrification and alternative anaerobic pathways of organic matter remineralization cannot account for the ammonium requirements of reported anammox rates. Here, we explore the significance of microaerobic respiration as a source of ammonium during organic matter degradation in the oxygen-deficient waters off Namibia and Peru. Experiments with additions of double-labelled oxygen revealed high aerobic activity in the upper OMZs, likely controlled by surface organic matter export. Consistently observed oxygen consumption in samples retrieved throughout the lower OMZs hints at efficient exploitation of vertically and laterally advected, oxygenated waters in this zone by aerobic microorganisms. In accordance, metagenomic and metatranscriptomic analyses identified genes encoding for aerobic terminal oxidases and demonstrated their expression by diverse microbial communities, even in virtually anoxic waters. Our results suggest that microaerobic respiration is a major mode of organic matter remineralization and source of ammonium (~45-100% in the upper oxygen minimum zones, and reconcile hitherto observed mismatches between ammonium producing and consuming processes therein.

  13. Nitrogen removal from wastewater and external waste activated sludge reutilization/reduction by simultaneous sludge fermentation, denitrification and anammox (SFDA).

    Science.gov (United States)

    Wang, Bo; Peng, Yongzhen; Guo, Yuanyuan; Zhao, Mengyue; Wang, Shuying

    2016-08-01

    This work demonstrates the feasibility of simultaneous nitrogen removal and external waste activated sludge (WAS) reutilization/reduction by using the synergy of sludge fermentation, denitrification and anammox processes in up-flow reactors (SFDA). Pre-treated domestic wastewater and synthetic wastewater (containing nitrite ∼20mg/L, ammonium ∼10mg/L in both) were fed to 1# and 2# SFDA, respectively. Long-term operation of 1# SFDA was investigated with achieving the peak ammonium removal rate of 0.021 and nitrite removal rate of 0.081kgN/(m(3)d) as nitrogen loading rate elevated from 0.075 to 0.106kgN/(m(3)d). Negative effect of dissolved oxygen on anammox or fermentation in the 2# SFDA was demonstrated negligible due to rapid depletion by microorganisms. Furthermore, a "net" sludge reduction of 38.8% was obtained due to sludge decay and organics consumption by denitrification. The SFDA process was expected to potentially be used for nitrogen removal and WAS reutilization/reduction in full-scale application. PMID:27140818

  14. Removal of Nitrogen and Phosphorus From Reject Water Using Chlorella vulgaris Algae After Partial Nitrification/Anammox Process.

    Science.gov (United States)

    Gutwinski, Piotr; Cema, Grzegorz

    2016-01-01

    Wastewater containing nutrients like ammonia, nitrite, nitrate and phosphates have been identified as the main cause of eutrophication in natural waters. Therefore, a suitable treatment is needed. In classical biological processes, nitrogen and phosphorus removal is expensive, especially due to the lack of biodegradable carbon, thus new methods are investigated. In this paper, the new possibility of nitrogen and phosphorus removal in side stream after the partial nitrification/Anammox process is proposed. Research was carried out in a lab-scale vertical tubular photobioreactor (VTR) fed with real reject water, from dewatering of digested sludge, after partial nitrification/Anammox process from lab-scale sequencing batch reactor (SBR). Nitrogen and phosphorus concentrations were measured every three days. The average nitrogen and phosphorus loads were 0.0503 ± 0.036 g N g(vss)/d and 0.0389 ± 0.013 g P g(vss)/d accordingly. Results have shown that microalgae were able to efficiently remove nitrogen and phosphorus. The average nitrogen removal was 36.46% and phosphorus removal efficiency varied between 93 and 100%. PMID:26803028

  15. Anaerobic digestion of solid material

    DEFF Research Database (Denmark)

    Vavilin, V.A.; Lokshina, L.Y.; Flotats, X.;

    2007-01-01

    A new multidimensional (3 and 2D) anaerobic digestion model for cylindrical reactor with non-uniform influent concentration distributions was developed to study the way in which mixing intensity affects the efficiency of continuous-flow anaerobic digestion. Batch experiments reported and simulated...... improve the continuous flow reactor performance at the relatively low influent methanogenic biomass concentration. In the continuously stirred tank reactor (CSTR) there are two steady states with and without methane production at slightly different values of initial methanogenic biomass concentration....... In the system, the threshold methanogenic biomass concentration existed because of inhibition by high VFA concentration. High methanogenic biomass concentration is required for efficient anaerobic digestion of MSW in order to avoid possible inhibition due to high VFA build-up. Thus, CSTR configuration might...

  16. RISK FACTORS IN NEONATAL ANAEROBIC INFECTIONS

    Directory of Open Access Journals (Sweden)

    M. S. Tabib

    2008-06-01

    Full Text Available Anaerobic bacteria are well known causes of sepsis in adults but there are few studies regarding their role in neonatal sepsis. In an attempt to define the incidence of neonatal anaerobic infections a prospective study was performed during one year period. A total number of 400 neonates under sepsis study were entered this investigation. Anaerobic as well as aerobic cultures were sent. The patients were subjected to comparison in two groups: anaerobic culture positive and anaerobic culture negative and this comparison were analyzed statistically. There were 7 neonates with positive anaerobic culture and 35 neonates with positive aerobic culture. A significant statistical relationship was found between anaerobic infections and abdominal distention and pneumonia. It is recommended for those neonates with abdominal distention and pneumonia refractory to antibiotic treatment to be started on antibiotics with anaerobic coverage.

  17. Anaerobic Digestion of Piggery Waste

    OpenAIRE

    Velsen, van, L.S.

    1981-01-01

    Anaerobic digestion is a biological process by which organic matter is converted to methane and carbon dioxide by microbes in the absence of air (oxygen). In nature, anaerobic conversions occur at all places where organic material accumulates and the supply of oxygen is deficient, e.g. in marshes and lake sediments. Microbial formation of methane also plays a role in the ruminant digestion.In digestion units, the external conditions acting upon the process can be regulated to speed it up as c...

  18. Anaerobic membrane bioreactors for municipal wastewater treatment

    OpenAIRE

    Fawehinmi, Folasade

    2006-01-01

    Anaerobic treatment has historically been considered unsuitable for the treatment of domestic wastewaters. The work presented in this thesis focuses on the incorporation of membranes into the anaerobic bioreactor to uncouple solid retention time and hydraulic retention time. This in turn prevents biomass washout and allows sufficient acclimatisation periods for anaerobes. However, the exposure of membranes to anaerobic biomass comes with its own inherent problems namely fouling. Fouling w...

  19. Molecular genetic studies on obligate anaerobic bacteria

    International Nuclear Information System (INIS)

    Molecular genetic studies on obligate anaerobic bacteria have lagged behind similar studies in aerobes. However, the current interest in biotechnology, the involvement of anaerobes in disease and the emergence of antibioticresistant strains have focused attention on the genetics of anaerobes. This article reviews molecular genetic studies in Bacteroides spp., Clostridium spp. and methanogens. Certain genetic systems in some anaerobes differ from those in aerobes and illustrate the genetic diversity among bacteria

  20. Viscosity evolution of anaerobic granular sludge

    NARCIS (Netherlands)

    Pevere, A.; Guibaud, G.; Hullebusch, van E.D.; Lens, P.N.L.; Baudu, M.

    2006-01-01

    The evolution of the apparent viscosity at steady shear rate of sieved anaerobic granular sludge (20¿315 ¿m diameter) sampled from different full-scale anaerobic reactors was recorded using rotation tests. The ¿limit viscosity¿ of sieved anaerobic granular sludge was determined from the apparent vis

  1. Kinetics and modeling of anaerobic digestion process

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Angelidaki, Irini; Ahring, Birgitte Kiær

    2003-01-01

    Anaerobic digestion modeling started in the early 1970s when the need for design and efficient operation of anaerobic systems became evident. At that time not only was the knowledge about the complex process of anaerobic digestion inadequate but also there were computational limitations. Thus...

  2. Isotopic Monitoring of N2O Emissions from Wastewater Treatment: Evidence for N2O Production Associated with Anammox Metabolism?

    Science.gov (United States)

    Harris, E. J.; Wunderlin, P.; Joss, A.; Emmenegger, L.; Kipf, M.; Wolf, B.; Mohn, J.

    2015-12-01

    Microbial production is the major source of N2O, the strongest greenhouse gas produced within the nitrogen cycle, and the most important stratospheric ozone destructant released in the 21st century. Wastewater treatment is an important and growing source of N2O, with best estimates predicting N2O emissions from this sector will have increased by >25% by 2020. Novel treatment employing partial nitritation-anammox, rather than traditional nitrification-denitrification, has the potential to achieve a neutral carbon footprint due to increased biogas production - if N2O production accounts for wastewater treatment can be applied to our understanding of N cycling in the natural environment. This study presents the first online isotopic measurements of offgas N2O from a partial-nitritation anammox reactor 1. The measured N2O isotopic composition - in particular the N2O isotopic site preference (SP = δ15Nα - δ15Nβ) - was used to understand N2O production pathways in the reactor. When N2O emissions peaked due to high dissolved oxygen concentrations, low SP showed that N2O was produced primarily via nitrifier denitrification by ammonia oxidizing bacteria (AOBs). N2O production by AOBs via NH2OH oxidation, in contrast, did not appear to be important under any conditions. Over the majority of the one-month measurement period, the measured SP was much higher than expected following our current understanding of N2O production pathways 2. SP reached 41‰ during normal operating conditions and achieved a maximum of 45‰ when nitrite was added under anoxic conditions. These results could be explained by unexpectedly strong heterotrophic N2O reduction despite low dissolved organic matter concentrations, or by an incomplete understanding of isotopic fractionation during N2O production from NH2OH oxidation by AOBs - however the explanation most consistent with all results is a previously unknown N2O production pathway associated with anammox metabolism. Harris et al. (2015

  3. Oxygen Effects in Anaerobic Digestion

    Directory of Open Access Journals (Sweden)

    Deshai Botheju

    2009-10-01

    Full Text Available Interaction of free oxygen in bio-gasification is a sparsely studied area, apart from the common argument of oxygen being toxic and inhibitory for anaerobic micro-cultures. Some studies have, however, revealed increased solubilisation of organic matter in the presence of some free oxygen in anaerobic digestion. This article analyses these counterbalancing phenomena with a mathematical modelling approach using the widely accepted biochemical model ADM 1. Aerobic oxidation of soluble carbon and inhibition of obligatory anaerobic organisms are modelled using standard saturation type kinetics. Biomass dependent first order hydrolysis kinetics is used to relate the increased hydrolysis rate with oxygen induced increase in biomass growth. The amended model, ADM 1-Ox (oxygen, has 25 state variables and 22 biochemical processes, presented in matrix form. The computer aided simulation tool AQUASIM 2.1 is used to simulate the developed model. Simulation predictions are evaluated against experimental data obtained using a laboratory batch test array comprising miniature anaerobic bio-reactors of 100 ml total volume each, operated under different initial air headspaces giving rise to the different oxygen loading conditions. The reactors were initially fed with a glucose solution and incubated at 35 Celsius, for 563 hours. Under the oxygen load conditions of 22, 44 and 88 mg/L, the ADM1-Ox model simulations predicted the experimental methane potentials quite adequately. Both the experimental data and the simulations suggest a linear reduction of methane potential with respect to the increase in oxygen load within this range.

  4. Anaerobic Treatment of Methanolic Wastes

    NARCIS (Netherlands)

    Lettinga, G.; Geest, van der A.Th.; Hobma, S.W.; Laan, van der J.B.R.

    1979-01-01

    Although it is well known that methanol can be fermented directly by a specific species of methane bacteria, viz. Methanosarcina barkeri, until now little information was available about the effect of important environmental factors on the anaerobic fermentation of methanol. As methanol can be the m

  5. Hotspots of anaerobic ammonia oxidation in land - freshwater interfaces

    DEFF Research Database (Denmark)

    Zhu, Guibing; Wang, Shanyun; Wang, Weidong;

    2013-01-01

    sampled fromlake riparian zones in North China. Laboratory incubations in the presence of ammonium or nitrate—at concentrations equivalent to no more than 10% of those detected in situ—yielded some of the highest potential anammox activities reported for natural environments to date. Potential rates of......For decades, the conversion of organic nitrogen to dinitrogen gas by heterotrophic bacteria, termed heterotrophic denitrification, was assumed to be the main pathway of nitrogen loss in natural ecosystems. Recently, however, autotrophic bacteria have been shown to oxidize ammonium in the absence of...... anammox peaked in sediments sampled from the interface between the land and the water, as did the abundance of annamox bacteria. Scaling our findings up to the entire lake system, we estimate that interfacial anammox hotspots account for the loss of 103 gNm-2 yr-1 from this lake region, and around one...

  6. Effect of incubation conditions on anaerobic susceptibility testing results.

    OpenAIRE

    Murray, P R; Niles, A C

    1982-01-01

    We determined the effect of performing antimicrobial susceptibility tests in five different anaerobic incubation systems: GasPak jar, large GasPak jar, evacuated-gassed anaerobic jar, anaerobic chamber, and Bio-Bag. Growth of the anaerobes was equivalent in all five incubation systems. The results of testing 38 anaerobes against 11 antimicrobial agents were comparable for the anaerobic jars and anaerobic chamber. However, discordant results were observed for metronidazole and cefamandole test...

  7. Anaerobic digestion of solid material

    DEFF Research Database (Denmark)

    Vavilin, V.A.; Lokshina, L.Y.; Flotats, X.; Angelidaki, Irini

    2007-01-01

    A new multidimensional (3 and 2D) anaerobic digestion model for cylindrical reactor with non-uniform influent concentration distributions was developed to study the way in which mixing intensity affects the efficiency of continuous-flow anaerobic digestion. Batch experiments reported and simulated...... improve the continuous flow reactor performance at the relatively low influent methanogenic biomass concentration. In the continuously stirred tank reactor (CSTR) there are two steady states with and without methane production at slightly different values of initial methanogenic biomass concentration. In...... failure. According to the distributed models a plug-flow reactor with non-uniform influent concentration distributions where methanogenic and hydrolytic microorganisms are separated has significant methane production and solids removal at the relatively low influent methanogenic biomass concentration...

  8. Anaerobic procedures of wastewater treatment

    OpenAIRE

    Zupančič, Tadeja

    2013-01-01

    Highly polluted wastewater is formed in dairies, pig farms and slaughterhouses. Before released into watercourses, wastewater should be properly processed with different treatment procedures in wastewater treatment plants. The thesis deals with the descriptions of mechanical, physical and chemical, and biological wastewater treatment procedures and the description of the factors which affect the reactions in wastewater treatment plants. I give special emphasis on anaerobic wastewater treatmen...

  9. Anaerobic digestion of aliphatic polyesters.

    Science.gov (United States)

    Šmejkalová, Pavla; Kužníková, Veronika; Merna, Jan; Hermanová, Soňa

    2016-01-01

    Anaerobic processes for the treatment of plastic materials waste represent versatile and effective approach in environmental protection and solid waste management. In this work, anaerobic biodegradability of model aliphatic polyesters, poly(L-lactic acid) (PLA), and poly(ɛ-caprolactone) (PCL), in the form of powder and melt-pressed films with varying molar mass, was studied. Biogas production was explored in batch laboratory trials at 55 ± 1°C under a nitrogen atmosphere. The inoculum used was thermophilic digested sludge (total solids concentration of 2.9%) from operating digesters at the Central Waste Water Treatment Plant in Prague, Czech Republic. Methanogenic biodegradation of PCLs typically yielded from 54 to 60% of the theoretical biogas yield. The biodegradability of PLAs achieved from 56 to 84% of the theoretical value. High biogas yield (up to 677 mL/g TS) with high methane content (more than 60%), comparable with conventionally processed materials, confirmed the potential of polyester samples for anaerobic treatment in the case of their exploitation in agriculture or as a packaging material in the food industry. PMID:27191559

  10. Mainstream partial nitritation and anammox in a 200,000 m(3)/day activated sludge process in Singapore: scale-down by using laboratory fed-batch reactor.

    Science.gov (United States)

    Yeshi, Cao; Hong, Kwok Bee; van Loosdrecht, Mark C M; Daigger, Glen T; Yi, Png Hui; Wah, Yuen Long; Chye, Chua Seng; Ghani, Yahya Abd

    2016-01-01

    A laboratory fed-batch reactor has been used to study under controlled conditions the performance of partial nitritation/anammox for the 200,000 m(3)/day step-feed activated sludge process at the Changi Water Reclamation Plant, Singapore. The similarity of the concentrations of NH4, NO2, NO3, PO4, suspended chemical oxygen demand (sCOD), pH, and alkalinity (ALK) between the on-site process and laboratory reactor illustrates that the laboratory fed-batch reactor can be used to simulate the site performance. The performance of the reactor fed by primary effluent illustrated the existence of anammox and heterotrophic denitrification and apparent excessive biological phosphorus removal as observed from the site. The performance of the reactor fed by final effluent proved the presence of anammox process on site. Both the laboratory reactor and on-site process showed that higher influent 5-day biochemical oxygen demand/total nitrogen (BOD5/TN) (COD/TN) ratio increases the nitrogen removal efficiency of the process. PMID:27386982

  11. Molecular ecology of anaerobic reactor systems

    DEFF Research Database (Denmark)

    Hofman-Bang, H. Jacob Peider; Zheng, D.; Westermann, Peter; Ahring, Birgitte Kiær; Raskin, L.

    2003-01-01

    Anaerobic reactor systems are essential for the treatment of solid and liquid wastes and constitute a core facility in many waste treatment plants. Although much is known about the basic metabolism in different types of anaerobic reactors, little is known about the microbes responsible for these ...... specific nucleic acid probes are discussed and exemplified by studies of anaerobic granular sludge, biofilm and digester systems...... malfunctions of anaerobic digesters occasionally experienced, leading to sub-optimal methane production and wastewater treatment. Using a variety of molecular techniques, we are able to determine which microorganisms are active, where they are active, and when they are active, but we still need to determine...... abundance of each microbe in anaerobic reactor systems by rRNA probing. This chapter focuses on various molecular techniques employed and problems encountered when elucidating the microbial ecology of anaerobic reactor systems. Methods such as quantitative dot blot/fluorescence in-situ probing using various...

  12. Sedimentary ladderane core lipids as potential indicators of hypoxia in the East China Sea

    Institute of Scientific and Technical Information of China (English)

    ZHAO Zongshan; CAO Yali; LI Li; SONG Guodong; YANG Hongmei; LIU Sumei; ZHAO Meixun

    2013-01-01

    Anammox (anaerobic ammonium oxidation) is an important process in many suboxic to anoxic marine environments for converting fixed nitrogen to N2,and has a major impact on the marine nitrogen cycle.Ladderane core lipids have been utilized as an indicator of the contribution of anammox to the marine nitrogen cycles.However,such studies have not been reported for the China seas and little is known about the importance ofanammox within the nitrogen cycle of these marginal seas.In the research reported here,the ladderane core lipid contents of 17 surface sediment samples from the East China Sea are reported,and their spatial distribution is investigated.C1s-[5]-ladderane FAME,C20-[5]-ladderane FAME and C20-[3]-ladderane FAME have all been detected,suggesting that the anammox bacteria are widely present within the study area.The total contents of the three ladderane lipids (ΣFAMEs) range from 24-355 ng/g (weight of dry sediments),with higher contents occurring in the Minzhe Mud Zone and broadly coincident with the spatial distribution of hypoxia.It is suggested that the sedimentary ladderane core lipids are mainly produced in the water column and their sedimentary contents can be used as indicators of water colunm hypoxia.

  13. Prokaryotic community composition involved production of nitrogen in sediments of Mejillones Bay

    International Nuclear Information System (INIS)

    Conventional denitrification and anaerobic ammonium oxidation (anammox) contributes to nitrogen loss in oxygen-deficient systems, thereby influencing many aspects of ecosystem function and global biogeochemistry. Mejillones Bay, northern Chile, presents ideal conditions to study nitrogen removal processes, because it is inserted in a coastal upwelling system, its sediments have anoxia and hypoxia conditions and under the influence of the Oxygen Minimum Zone (OMZ), unknown processes that occur there and what are the microbial communities responsible for their removal. Microbial communities associated with coastal sediments of Mejillones Bay were studied by denaturing gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH), by incubation experiments with 15N isotope tracers were studied nitrogen loss processes operating in these sediments. DGGE analysis showed high bacterial diversity, certain redundant phylotypes and differences in community structure given by the depth; this reflects the microbial community adaptations to environmental conditions. A large fraction (up to 70%) of DAPI-stained cells hybridized with the bacterial probes. Nearly 52-90% of the cell could be further identified to know phyla. Members of the Cytophaga-Flavobacterium cluster were most abundant in the sediments (13-26%), followed by Proteobacteria. Isotopic tracer experiments for the sediments studied indicated that nitrogen loss processes that predominated were performed by denitrifying communities (43.31-111.20 μMd-1) was not possible to detect anammox in the area and not anammox bacteria were detected

  14. Nitrate-transformations during simulated drought on a restored floodplain

    Science.gov (United States)

    Hoagland, B.; Russo, T. A.; Schmidt, C. M.; Tran, D.

    2015-12-01

    Water resources in the California Central Valley face challenges due to recurring drought, aging levee systems, and nitrate contamination. As decisions are made to restore floodplain connectivity, soil microbial metabolic pathways such as denitrification, anaerobic ammonium oxidation (anammox), and dissimilatory nitrate reduction to ammonium (DNRA) transform nitrate under saturated soil conditions and may each affect downstream water quality. However, few studies have quantified the contribution of all three pathways to nitrate retention in freshwater systems, and specifically in restored floodplains. Additionally, no former studies quantify the rates of these microbial nitrate transformations during floods after prolonged periods of drought. To test how flood duration impacts nitrogen cycling we added 15N-enriched tracer to soil mesocosms to measure denitrification, anammox, and DNRA transformation rates. In July 2015, we extracted seven soil mesocosms from the floodplain and riverbed of the Lower Cosumnes River in the San Joaquin Basin of California. Cosumnes River water enriched with 15N-NO3- tracer was pumped into each mesocosm at a constant rate simulating flood durations of 20 h, 30 h, and 96 h. Samples were collected from the surface water, soil pore water, drain water, and sediment for measurements of NO3-, NO2-, NH4+, gas isotopes, and DNA extraction. This study aims to demonstrate the relevance of anammox and DNRA to total nitrate retention and characterize the hydrologic conditions most favorable to each pathway.

  15. Hydrologic Controls on Nitrogen Cycling Processes and Functional Gene Abundance in Sediments of a Groundwater Flow-Through Lake.

    Science.gov (United States)

    Stoliker, Deborah L; Repert, Deborah A; Smith, Richard L; Song, Bongkeun; LeBlanc, Denis R; McCobb, Timothy D; Conaway, Christopher H; Hyun, Sung Pil; Koh, Dong-Chan; Moon, Hee Sun; Kent, Douglas B

    2016-04-01

    The fate and transport of inorganic nitrogen (N) is a critically important issue for human and aquatic ecosystem health because discharging N-contaminated groundwater can foul drinking water and cause algal blooms. Factors controlling N-processing were examined in sediments at three sites with contrasting hydrologic regimes at a lake on Cape Cod, MA. These factors included water chemistry, seepage rates and direction of groundwater flow, and the abundance and potential rates of activity of N-cycling microbial communities. Genes coding for denitrification, anaerobic ammonium oxidation (anammox), and nitrification were identified at all sites regardless of flow direction or groundwater dissolved oxygen concentrations. Flow direction was, however, a controlling factor in the potential for N-attenuation via denitrification in the sediments. Potential rates of denitrification varied from 6 to 4500 pmol N/g/h from the inflow to the outflow side of the lake, owing to fundamental differences in the supply of labile organic matter. The results of laboratory incubations suggested that when anoxia and limiting labile organic matter prevailed, the potential existed for concomitant anammox and denitrification. Where oxic lake water was downwelling, potential rates of nitrification at shallow depths were substantial (1640 pmol N/g/h). Rates of anammox, denitrification, and nitrification may be linked to rates of organic N-mineralization, serving to increase N-mobility and transport downgradient. PMID:26967929

  16. The feasibility of an up-flow partially aerated biological filter (U-PABF) for nitrogen and COD removal from domestic wastewater.

    Science.gov (United States)

    Tao, Chen; Peng, Tong; Feng, Chuanping; Chen, Nan; Hu, Qili; Hao, Chunbo

    2016-10-01

    An up-flow partially aerated biological filter (U-PABF) was developed to study the removal of nitrogen and chemical oxygen demand (COD) from synthetic domestic wastewater. The removal of NH4(+)-N was primarily attributed to adsorption in the zeolite U-PABF and to bioprocesses in the ceramic U-PABF. When the hydraulic retention time (HRT) was 5.2h, the ceramic U-PABF achieved a good performance and the NH4(+)-N, total nitrogen (TN), and COD removal efficiency reached 99.08±8.79%, 72.83±0.68%, and 89.38±1.04%, respectively. The analysis of NH4(+)-N, NO3(-)-N, NO2(-)-N, and TN at different depths revealed the simultaneous existence of nitrification-denitrification, and anaerobic ammonium oxidation (anammox) in ceramic U-PABF. Illumina pyrosequencing confirmed the existence of Planctomycetes, which are responsible for anammox. The results indicated that the nitrification-denitrification and anammox all contributed to the high removal of NH4(+)-N, TN, and COD in the U-PABF. PMID:27372011

  17. Hydrologic controls on nitrogen cycling processes and functional gene abundance in sediments of a groundwater flow-through lake

    Science.gov (United States)

    Stoliker, Deborah L.; Repert, Deborah A.; Smith, Richard L.; Song, Bongkeun; LeBlanc, Denis R.; McCobb, Timothy D.; Conaway, Christopher; Hyun, Sung Pil; Koh, Dong-Chan; Moon, Hee Sun; Kent, Douglas B.

    2016-01-01

    The fate and transport of inorganic nitrogen (N) is a critically important issue for human and aquatic ecosystem health because discharging N-contaminated groundwater can foul drinking water and cause algal blooms. Factors controlling N-processing were examined in sediments at three sites with contrasting hydrologic regimes at a lake on Cape Cod, MA. These factors included water chemistry, seepage rates and direction of groundwater flow, and the abundance and potential rates of activity of N-cycling microbial communities. Genes coding for denitrification, anaerobic ammonium oxidation (anammox), and nitrification were identified at all sites regardless of flow direction or groundwater dissolved oxygen concentrations. Flow direction was, however, a controlling factor in the potential for N-attenuation via denitrification in the sediments. Potential rates of denitrification varied from 6 to 4500 pmol N/g/h from the inflow to the outflow side of the lake, owing to fundamental differences in the supply of labile organic matter. The results of laboratory incubations suggested that when anoxia and limiting labile organic matter prevailed, the potential existed for concomitant anammox and denitrification. Where oxic lake water was downwelling, potential rates of nitrification at shallow depths were substantial (1640 pmol N/g/h). Rates of anammox, denitrification, and nitrification may be linked to rates of organic N-mineralization, serving to increase N-mobility and transport downgradient.

  18. In vitro susceptibility testing of anaerobic bacteria.

    Science.gov (United States)

    Washington, J A

    1979-01-01

    In vitro susceptibility testing of anaerobic bacteria should be limited to isolates from persistent or recurrent infections that have been treated adequately and appropriately with antimicrobial agents and, in reference centers, to collections of isolates in order to monitor alterations in susceptibility of species to various antimicrobial agents. An agar dilution reference method is being evaluated currently; however, practicality limits sporadic testing of single isolates to disk elution or broth dilution techniques. No single disk diffusion method has yet been found to be acceptable for testing anaerobic bacteria, and the results obtained with standardized procedures for aerobic and facultatively anaerobic bacteria are not applicable to anaerobic bacteria. PMID:288163

  19. Performance of a completely autotrophic nitrogen removal over nitrite process for treating wastewater with different substrates at ambient temperature

    Institute of Scientific and Technical Information of China (English)

    Xiaoyan Chang; Dong Li; Yuhai Liang; Zhuo Yang; Shaoming Cui; Tao Liu; Huiping Zeng

    2013-01-01

    The stability and parameters of a bio-ceramic filter for completely autotrophic nitrogen removal were investigated.The completely autotrophic nitrogen removal over nitrite (CANON) reactor was fed with different concentrations of ammonia (400,300,and 200 mg N/L) but constant influent ammonia load.The results showed that the CANON system can achieve good treatment performance at ambient temperature (15-23℃).The average removal rate and removal loading of NH4 +-N and TN was 83.90%,1.26 kg N/(m3.day),and 70.14%,1.09 kg N/(m3.day),respectively.Among the influencing factors like pH,dissolved oxygen and alkalinity,it was indicated that the pH was the key parameter of the performance of the CANON system.Observing the variation of pH would contribute to better control of the CANON system in an intuitive and fast way.Denaturing gradient gel electrophoresis analysis of microorganisms further revealed that there were some significant changes in the community structure of ammonium oxidizing bacteria,which had low diversity in different stages,while the species of anaerobic ammonium oxidizing (anammox) bacteria were fewer and the community composition was relatively stable.These observations showed that anaerobic ammonia oxidation was more stable than the aerobic ammonia oxidation,which could explain that why the CANON system maintained a good removal efficiency under the changing substrate conditions.

  20. Anaerobic Capacities of Leaf Litter

    OpenAIRE

    Kusel, K.; Drake, H L

    1996-01-01

    Leaf litter displayed a capacity to spontaneously form organic acids, alcohols, phenolic compounds, H(inf2), and CO(inf2) when incubated anaerobically at 20(deg)C either as buffered suspensions or in a moistened condition in microcosms. Acetate was the predominant organic product formed regardless of the degree of litter decomposition. Initial rates of acetate formation in litter suspensions and microcosms approximated 2.6 and 0.53 (mu)mol of acetate per g (dry weight) of litter per h, respec...

  1. Anaerobic digestion of coffee waste

    OpenAIRE

    L. Neves; Ribeiro, R.; Oliveira, Rosário; Alves, M. M.

    2005-01-01

    The anaerobic co-digestion of five different by-products from instant coffee substitutes production was studied in mesophilic conditions. The co-substrate was the excess of sewage sludge from the wastewater treatment plant located in the same coffee factory. Four of the tested wastes produced methane in the range of 0.24-0.28 m³CH4(STP)/kgVSinitial . Reduction of 50-73% in total solids and 75-80% in volatile solids were obtained and the hydrolysis rate constants were in the ran...

  2. Alternative nitrate reduction pathways in experimentally fertilized New England salt marshes

    DEFF Research Database (Denmark)

    Uldahl, Anne; Banta, Gary Thomas; Boegh, Eva;

    ongoing ecosystem level nutrient additions experiments in two New England salt marshes, Plum Island Sound (NO3- additions since 2003) and Great Sippewissett Marsh (fertilizer additions since the 1970's) to examine the relative importance of these NO3- reduction pathways in salt marshes. Sediments from......Nitrate present or generated in any benthic ecosystem can be reduced by a number of microbial pathways, most notably denitrification, anaerobic ammonium oxidation (anammox) and dissimilatory nitrate reduction to ammonium (DNRA). The first two processes remove of biologically available N from...... the ecosystem in the form of gaseous N2, while the last process transforms of NO3- to another biologically available form, NH4+, and thus merely recycles N. Salt marshes are important ecosystems for the cycling, retention and removal of biologically available N transported from land to the oceans. We used...

  3. Anaerobic granular sludge and biofilm reactors

    DEFF Research Database (Denmark)

    Skiadas, Ioannis V.; Gavala, Hariklia N.; Schmidt, Jens Ejbye; Ahring, Birgitte Kiær

    2003-01-01

    role of the anaerobic digestion in the wastewater treatment plants from a pre-treatment method to the main biological treatment method. The application of staged high-rate anaerobic digesters has shown the larger potential among the recent developments in this direction. The most common high...

  4. Anaerobic Infections in Children with Neurological Impairments.

    Science.gov (United States)

    Brook, Itzhak

    1995-01-01

    Children with neurological impairments are prone to develop serious infection with anaerobic bacteria. The most common anaerobic infections are decubitus ulcers; gastrostomy site wound infections; pulmonary infections (aspiration pneumonia, lung abscesses, and tracheitis); and chronic suppurative otitis media. The unique microbiology of each of…

  5. Instrumentation in anaerobic treatment - research and practice

    NARCIS (Netherlands)

    Spanjers, H.; Lier, van J.B.

    2006-01-01

    High rate anaerobic treatment reactors are able to uncouple solids and liquid retention time, resulting in high biomass concentrations. Principal advantages of anaerobic treatment include: energy efficiency, low biomass yield, low nutrient requirement and high volumetric organic loadings. In order t

  6. Atrazine removal in Danish anaerobic aquifers

    DEFF Research Database (Denmark)

    Pedersen, Philip Grinder; Arildskov, N.P.; Albrechtsen, Hans-Jørgen

    2002-01-01

    The pesticide atrazine (6-chloro-N-2-ethyl-N-4-isopropyl-1,3,5-triazine -2,4-diamine) was removed from the water phase in anaerobic laboratory batch incubations with sediment and groundwater from a number of Danish anaerobic aquifers, but not in incubations from aerobic aquifers. The removal...

  7. Anaerobic degradation of linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

    Mogensen, Anders Skibsted; Haagensen, Frank; Ahring, Birgitte Kiær

    2003-01-01

    increases during anaerobic stabilization due to transformation of easily degradable organic matter. Hence, LAS is regarded as resistant to biodegradation under anaerobic conditions. We present data from a lab-scale semi-continuously stirred tank reactor (CSTR) spiked with linear dodecylbenzene sulfonate (C...

  8. Prospects of Anaerobic Digestion Technology in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    As the world's largest developing country, China must face the problem of managing municipal solid waste, and the challenge of organic waste disposal is even more serious. Considering the characteristics of traditional waste disposal technologies and the subsequent secondary pollution, anaerobic digestion has various advantages such as reduction in the land needed for disposal and preservation of environmental quality. In light of the energy crisis, this paper focuses on the potential production of biogas from biowaste through anaerobic digestion processes, the problems incurred by the waste collection system, and the efficiency of the anaerobic digestion process. Use of biogas in a combined heat and power cogeneration system is also discussed. Finally, the advantages of anaerobic digestion technology for the Chinese market are summarized. The anaerobic digestion is suggested to be a promising treating technology for the organic wastes in China.

  9. Anaerobic biorefinery: Current status, challenges, and opportunities.

    Science.gov (United States)

    Sawatdeenarunat, Chayanon; Nguyen, Duc; Surendra, K C; Shrestha, Shilva; Rajendran, Karthik; Oechsner, Hans; Xie, Li; Khanal, Samir Kumar

    2016-09-01

    Anaerobic digestion (AD) has been in use for many decades. To date, it has been primarily aimed at treating organic wastes, mainly manures and wastewater sludge, and industrial wastewaters. However, with the current advancements, a more open mind is required to look beyond these somewhat restricted original applications of AD. Biorefineries are such concepts, where multiple products including chemicals, fuels, polymers etc. are produced from organic feedstocks. The anaerobic biorefinery concept is now gaining increased attention, utilizing AD as the final disposal step. This review aims at evaluating the potential significance of anaerobic biorefineries, including types of feedstocks, uses for the produced energy, as well as sustainable applications of the generated residual digestate. A comprehensive analysis of various types of anaerobic biorefineries has been developed, including both large-scale and household level applications. Finally, future directives are highlighted showing how anaerobic biorefinery concept could impact the bioeconomy in the near future. PMID:27005786

  10. Anaerobic granular sludge and biofilm reactors

    DEFF Research Database (Denmark)

    Skiadas, Ioannis V.; Gavala, Hariklia N.; Schmidt, Jens Ejbye;

    2003-01-01

    The long retention time of the active biomass in the high-rate anaerobic digesters is the key factor for the successful application of the high rate anaerobic wastewater treatment. The long solids retention time is achieved due to the specific reactor configuration and it is enhanced...... by the immobilization of the biomass, which forms static biofilms, particle-supported biofilms, or granules depending on the reactor's operational conditions. The advantages of the high-rate anaerobic digestion over the conventional aerobic wastewater treatment methods has created a clear trend for the change...... of the role of the anaerobic digestion in the wastewater treatment plants from a pre-treatment method to the main biological treatment method. The application of staged high-rate anaerobic digesters has shown the larger potential among the recent developments in this direction. The most common high...

  11. Molecular ecology of anaerobic reactor systems

    DEFF Research Database (Denmark)

    Hofman-Bang, H. Jacob Peider; Zheng, D.; Westermann, Peter;

    2003-01-01

    Anaerobic reactor systems are essential for the treatment of solid and liquid wastes and constitute a core facility in many waste treatment plants. Although much is known about the basic metabolism in different types of anaerobic reactors, little is known about the microbes responsible...... to the abundance of each microbe in anaerobic reactor systems by rRNA probing. This chapter focuses on various molecular techniques employed and problems encountered when elucidating the microbial ecology of anaerobic reactor systems. Methods such as quantitative dot blot/fluorescence in-situ probing using various...... and malfunctions of anaerobic digesters occasionally experienced, leading to sub-optimal methane production and wastewater treatment. Using a variety of molecular techniques, we are able to determine which microorganisms are active, where they are active, and when they are active, but we still need to determine...

  12. Long-term operation performance and variation of substrate tolerance ability in an anammox attached film expanded bed (AAFEB) reactor.

    Science.gov (United States)

    Zhang, Yanlong; Niu, Qigui; Ma, Haiyuan; He, Shilong; Kubota, Kengo; Li, Yu-You

    2016-07-01

    An anammox attached film expanded bed (AAFEB) reactor was operated to study the long-term performance and the variation of substrate tolerance ability. The results indicated that the nitrogen loading potential (NLP) was significantly enhanced from 13.56gN·(L·d)(-)(1) to 20.95gN·(L·d)(-)(1) during the stable operation period. The inhibitory concentration of 10% (IC10) for free ammonia (FA), free nitrous acid (FNA) and SNinf (diluted substrate concentration) increased from 18mg/L, 12μgL(-1) and 370mgNL(-)(1) to 31mg/L, 19μgL(-1) and 670mgNL(-)(1), respectively. However, the substrate shock of 2500mgNL(-)(1) for 24h terribly weakened the treatment performance and substrate tolerance ability of the reactor. The results of batch tests indicated that the existence of lag phase made the AAFEB reactor more vulnerable to substrate variation. The SNinf was accurate to be used to monitor the reactor performance and should be maintained below 320mgNL(-)(1) to ensure the absolute stable operation. PMID:26995619

  13. Cultivable Anaerobic Microbiota of Infected Root Canals

    Directory of Open Access Journals (Sweden)

    Takuichi Sato

    2012-01-01

    Full Text Available Objective. Periapical periodontitis is an infectious and inflammatory disease of the periapical tissues caused by oral bacteria invading the root canal. In the present study, profiling of the microbiota in infected root canals was performed using anaerobic culture and molecular biological techniques for bacterial identification. Methods. Informed consent was obtained from all subjects (age ranges, 34–71 years. Nine infected root canals with periapical lesions from 7 subjects were included. Samples from infected root canals were collected, followed by anaerobic culture on CDC blood agar plates. After 7 days, colony forming units (CFU were counted and isolated bacteria were identified by 16S rRNA gene sequencing. Results. The mean bacterial count (CFU in root canals was (0.5±1.1×106 (range 8.0×101–3.1×106, and anaerobic bacteria were predominant (89.8%. The predominant isolates were Olsenella (25.4%, Mogibacterium (17.7%, Pseudoramibacter (17.7%, Propionibacterium (11.9% and Parvimonas (5.9%. Conclusion. The combination of anaerobic culture and molecular biological techniques makes it possible to analyze rapidly the microbiota in infected root canals. The overwhelming majority of the isolates from infected root canals were found to be anaerobic bacteria, suggesting that the environment in root canals is anaerobic and therefore support the growth of anaerobes.

  14. Cryptic or day-to-day parts of the riverbed N cycle - new challenges for 15N

    Science.gov (United States)

    Trimmer, Mark; Ouyang, Liao; Lansdown, Katrina

    2016-04-01

    The discovery of anaerobic ammonium oxidation (anammox) not only changed our understanding of the nitrogen cycle in aquatic ecosystems but it also undermined some of the key 15N techniques used to study it. Reformulations of principle equations and the development of new 15N2 and 15N2O techniques enabled the simultaneous quantification of N2 production by anammox and denitrification in mainly soft, cohesive sediments where redox gradients are clearly defined and solute exchanged governed by diffusion. At the heart of the application of 15N, for the quantification of natural 14N cycling, is the key assumption that the respective pools of 15N and 14N are evenly mixed and that both are cycled without bias towards each other. Recent evidence, however, from a variety of aquatic ecosystems, suggests that this may not be the case. For example, organic N may be oxidised directly to N2 gas without ever mixing with the inorganic pool or inorganic intermediates (e.g. nitrite) are 'shunted' internally and also fail to mix evenly with the applied tracer pool. Our most recent work in permeable, oxic gravel riverbeds presents some particular challenges to the application of 15N. In these systems, a tight coupling between aerobic nitrification and anaerobic N2 production - in the presence of 100

  15. Anaerobic xylose fermentation by Spathaspora passalidarum

    DEFF Research Database (Denmark)

    Hou, Xiaoru

    2012-01-01

    reductase (XR) and NAD+-dependent xylitol dehydrogenase (XDH). Thus, the capacity of S. passalidarum to utilize xylose under anaerobic conditions is possibly due to the balance between the cofactor’s supply and demand through this XR–XDH pathway. Only few XRs with NADH preference have been reported so far....... 2-Deoxy glucose completely inhibited the conversion of xylose by S. passalidarum under anaerobic conditions, but only partially did that under aerobic conditions. Thus, xylose uptake by S. passalidarum may be carried out by different xylose transport systems under anaerobic and aerobic conditions...

  16. Potential for anaerobic conversion of xenobiotics

    DEFF Research Database (Denmark)

    Mogensen, Anders Skibsted; Dolfing, J.; Haagensen, Frank;

    2003-01-01

    This review covers the latest research on the anaerobic biodegradation of aromatic xenobiotic compounds, with emphasis on surfactants, polycyclic aromatic hydrocarbons, phthalate esters, polychlorinated biphenyls, halogenated phenols, and pesticides. The versatility of anaerobic reactor systems...... regarding the treatment of xenobiotics is shown with the focus on the UASB reactor, but the applicability of other reactor designs for treatment of hazardous waste is also included. Bioaugmentation has proved to be a viable technique to enhance a specific activity in anaerobic reactors and recent research...... on reactor and in situ bioaugmentation is reported....

  17. Anaerobic respirometry as a tool for substrate characterisation aiming at modelling of manures anaerobic modelling of manures anaerobic digestion

    OpenAIRE

    Girault, R.; Sadowski, A.G.; Béline, F.

    2010-01-01

    Modelling of anaerobic digestion is more and more used as a tool for process optimization or interpreting observed phenomena within research projects. The most used model is the Anaerobic Digestion Model n°1 (ADM1) but some other models are also available (either simpler or more complex). Whatever the model, one of the major key issue is the fractionation and characterisation of the influent. For substrates like activated sludge from wastewater treatment plants, detailed influent characterisa...

  18. Anaerobe Tolerance to Oxygen and the Potentials of Anaerobic and Aerobic Cocultures for Wastewater Treatment

    OpenAIRE

    1997-01-01

    The anaerobic treatment processes are considered to be well-established methods for the elimination of easily biodegradable organic matter from wastewaters. Some difficulties concerning certain wastewaters are related to the possible presence of dissolved oxygen. The common belief is that anaerobes are oxygen intolerant. Therefore, the common practice is to use sequencing anaerobic and aerobic steps in separate tanks. Enhanced treatment by polishing off the residual biodegradable oxygen deman...

  19. Characterizing the Anaerobic Response of Chlamydomonas reinhardtii by Quantitative Proteomics

    OpenAIRE

    Terashima, Mia; Specht, Michael; Naumann, Bianca; Hippler, Michael

    2010-01-01

    The versatile metabolism of the green alga Chlamydomonas reinhardtii is reflected in its complex response to anaerobic conditions. The anaerobic response is also remarkable in the context of renewable energy because C. reinhardtii is able to produce hydrogen under anaerobic conditions. To identify proteins involved during anaerobic acclimation as well as to localize proteins and pathways to the powerhouses of the cell, chloroplasts and mitochondria from C. reinhardtii in aerobic and anaerobic...

  20. Anaerobe Tolerance to Oxygen and the Potentials of Anaerobic and Aerobic Cocultures for Wastewater Treatment

    Directory of Open Access Journals (Sweden)

    M.T. Kato

    1997-12-01

    Full Text Available The anaerobic treatment processes are considered to be well-established methods for the elimination of easily biodegradable organic matter from wastewaters. Some difficulties concerning certain wastewaters are related to the possible presence of dissolved oxygen. The common belief is that anaerobes are oxygen intolerant. Therefore, the common practice is to use sequencing anaerobic and aerobic steps in separate tanks. Enhanced treatment by polishing off the residual biodegradable oxygen demand from effluents of anaerobic reactors, or the biodegradation of recalcitrant wastewater pollutants, usually requires sequenced anaerobic and aerobic bacteria activities. However, the combined activity of both bacteria can also be obtained in a single reactor. Previous experiments with either pure or mixed cultures showed that anaerobes can tolerate oxygen to a certain extent. The oxygen toxicity to methanogens in anaerobic sludges was quantified in batch experiments, as well as in anaerobic reactors. The results showed that methanogens have a high tolerance to oxygen. In practice, it was confirmed that dissolved oxygen does not constitute any detrimental effect on reactor treatment performance. This means that the coexistence of anaerobic and aerobic bacteria in one single reactor is feasible and increases the potentials of new applications in wastewater treatment

  1. Anaerobic degradation of linear alkylbenzene sulfonate

    DEFF Research Database (Denmark)

    Mogensen, Anders Skibsted; Haagensen, Frank; Ahring, Birgitte Kiær

    2003-01-01

    increases during anaerobic stabilization due to transformation of easily degradable organic matter. Hence, LAS is regarded as resistant to biodegradation under anaerobic conditions. We present data from a lab-scale semi-continuously stirred tank reactor (CSTR) spiked with linear dodecylbenzene sulfonate (C......% of the added C-12 LAS was bioavailable and 20% was biotransformed when spiking with 100 mg/L of C-12 LAS and a TS concentration of 14.2 mg/L. Enhanced bioavailability of C-12 LAS was obtained in an upflow anaerobic sludge blanket (UASB) reactor inoculated with granular sludge and sewage sludge. Biodegradation......Linear alkylbenzene sulfonate (LAS) found in wastewater is removed in the wastewater treatment facilities by sorption and aerobic biodegradation. The anaerobic digestion of sewage sludge has not been shown to contribute to the removal. The concentration of LAS based on dry matter typically...

  2. Anaerobic membrane bioreactor under extreme conditions (poster)

    OpenAIRE

    Munoz Sierra, J.D.; De Kreuk, M.K.; Spanjers, H.; van Lier, J B

    2013-01-01

    Membrane bioreactors ensure biomass retention by the application of micro or ultrafiltration processes. This allows operation at high sludge concentrations. Previous studies have shown that anaerobic membrane bioreactors is an efficient way to retain specialist microorganisms for treating wastewaters from different industries such as coke, textile, food, and chemical. However, few research has been found into the use of membrane bioreactors for anaerobic treatment of wastewater under extreme ...

  3. Anaerobic Biodegradability of Agricultural Renewable Fibers

    OpenAIRE

    Shi, Bo; Lortscher, Peter; Palfery, Doris

    2013-01-01

    Natural fiber-based paper and paperboard products are likely disposed of in municipal wastewater, composting, or landfill after an intended usage. However, there are few studies reporting anaerobic sludge digestion and biodegradability of agricultural fibers although the soiled sanitary products, containing agricultural fibers, are increasingly disposed of in municipal wastewater or conventional landfill treatment systems, in which one or more unit operations are anaerobic digestion. We condu...

  4. Psychrophilic anaerobic treatment of low strength wastewaters.

    OpenAIRE

    Rebac, S.

    1998-01-01

    The main objective of this thesis was to design a high-rate anaerobic system for the treatment low strength wastewaters under psychrophilic conditions.Psychrophilic (3 to 20 °C) anaerobic treatment of low strength synthetic and malting wastewater was investigated using a single and two stage expanded granular sludge bed (EGSB) reactor system. The chemical oxygen demand (COD) removal efficiencies found in the experiments with synthetic wastewater exceeded 90 % in the single stage reactor at im...

  5. Anaerober Abbau von Kresolen und Monohydroxybenzoaten

    OpenAIRE

    Müller, Jochen A.

    2000-01-01

    All aromatic compounds are potential substrates for microorganisms. Hence, microorganisms play an eminent role in the global carbon cycle. The present work describes the anaerobic degradation of cresols and toluene, both bulk chemicals of the petroleum industry, and the anaerobic degradation of 3-hydroxybenzoate, a model compound for degradation of lignin-monomers. Degradation pathways for these aromatic substrates are postulated on the basis of in vitro measurements of key enzymes in various...

  6. Anaerobic digester for treatment of organic waste

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, V. K. [Indian Insitute of Technology, Delhi (India)]|[ENEA, Centro Ricerche Trisaia, Matera (Italy); Fortuna, F.; Canditelli, M.; Cornacchia, G. [ENEA, Centro Ricerche Trisaia, Matera (Italy). Dipt. Ambiente; Farina, R. [ENEA, centro Ricerche ``Ezio Clementel``, Bologna (Italy). Dipt. Ambiente

    1997-09-01

    The essential features of both new and more efficient reactor systems and their appropriate applications for various organic waste management situations, description of several working plants are discussed in the present communication. It is hoped that significant development reported here would be useful in opening a new vista to the application of anaerobic biotechnology for the waste treatment of both low/high organic strength and specialized treatment for toxic substances, using appropriate anaerobic methods.

  7. Anaerobic Digestion of Paper Mill Wastewater

    OpenAIRE

    Shreeshivadasan Chelliapan; Siti Baizura Mahat; Md. Fadjil Md. Din; A. Yuzir; Othman, N.

    2012-01-01

    In general, paper mill wastewater contains complex organic substances which could not be treated completely using conventional treatment processes, e.g. aerobic processes. As a result, anaerobic technology is a promising alternative for paper mill wastewater treatment due to its ability to degrade hard organic compounds. In the present study, treatment of paper mill wastewater using a stage anaerobic reactor was investigated. The more specific objectives of this study were to confirm whether ...

  8. Sleep Deprivation Induced Anxiety and Anaerobic Performance

    OpenAIRE

    Selma Arzu Vardar; Levent Öztürk; Cem Kurt; Erdogan Bulut; Necdet Sut; Erdal Vardar

    2007-01-01

    The aim of this study was to investigate the effects of sleep deprivation induced anxiety on anaerobic performance. Thirteen volunteer male physical education students completed the Turkish version of State Anxiety Inventory and performed Wingate anaerobic test for three times: (1) following a full-night of habitual sleep (baseline measurements), (2) following 30 hours of sleep deprivation, and (3) following partial-night sleep deprivation. Baseline measurements were performed the day before ...

  9. EFFECT OF MUSIC ON ANAEROBIC EXERCISE PERFORMANCE

    OpenAIRE

    Atan, T.

    2013-01-01

    For years, mostly the effects of music on cardiorespiratory exercise performance have been studied, but a few studies have examined the effect of music on anaerobic exercise. The purpose of this study was to assess the effect of listening to music and its rhythm on anaerobic exercise: on power output, heart rate and the concentration of blood lactate. 28 male subjects were required to visit the laboratory on 6 occasions, each separated by 48 hours. Firstly, each subject performed the Running-...

  10. Comparative Studies of Alternative Anaerobic Digestion Technologies

    OpenAIRE

    Inman, David C.

    2004-01-01

    Washington D.C. Water and Sewage Authority is planning to construct a new anaerobic digestion facility at its Blue Plains WWTP by 2008. The research conducted in this study is to aid the designers of this facility by evaluating alternative digestion technologies. Alternative anaerobic digestion technologies include thermophilic, acid/gas phased, and temperature phased digestion. In order to evaluate the relative merits of each, a year long study evaluated the performance of bench scale dig...

  11. SLEEP DEPRIVATION INDUCED ANXIETY AND ANAEROBIC PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Selma Arzu Vardar

    2007-12-01

    Full Text Available The aim of this study was to investigate the effects of sleep deprivation induced anxiety on anaerobic performance. Thirteen volunteer male physical education students completed the Turkish version of State Anxiety Inventory and performed Wingate anaerobic test for three times: (1 following a full-night of habitual sleep (baseline measurements, (2 following 30 hours of sleep deprivation, and (3 following partial-night sleep deprivation. Baseline measurements were performed the day before total sleep deprivation. Measurements following partial sleep deprivation were made 2 weeks later than total sleep deprivation measurements. State anxiety was measured prior to each Wingate test. The mean state anxiety following total sleep deprivation was higher than the baseline measurement (44.9 ± 12.9 vs. 27.6 ± 4.2, respectively, p = 0.02 whereas anaerobic performance parameters remained unchanged. Neither anaerobic parameters nor state anxiety levels were affected by one night partial sleep deprivation. Our results suggest that 30 hours continuous wakefulness may increase anxiety level without impairing anaerobic performance, whereas one night of partial sleep deprivation was ineffective on both state anxiety and anaerobic performance

  12. Illumina MiSeq sequencing reveals the key microorganisms involved in partial nitritation followed by simultaneous sludge fermentation, denitrification and anammox process.

    Science.gov (United States)

    Wang, Bo; Peng, Yongzhen; Guo, Yuanyuan; Zhao, Mengyue; Wang, Shuying

    2016-05-01

    A combined process including a partial nitritation SBR (PN-SBR) followed by a simultaneous sludge fermentation, denitrification and anammox reactor (SFDA) was established to treat low C/N domestic wastewater in this study. An average nitrite accumulation rate of 97.8% and total nitrogen of 9.4mg/L in the effluent was achieved during 140days' operation. The underlying mechanisms were investigated by using Illumina MiSeq sequencing to analyze the microbial community structures in the PN-SBR and SFDA. Results showed that the predominant bacterial phylum was Proteobacteria in the external waste activated sludge (WAS, added to the SFDA) and SFDA while Bacteroidetes in the PN-SBR. Further study indicated that in the PN-SBR, the dominant nitrobacteria, Nitrosomonas genus, facilitated nitritation and little nitrate was generated in the PN-SBR effluent. In the SFDA, the co-existence of functional microorganisms Thauera, Candidatus Anammoximicrobium and Pseudomonas were found to contribute to simultaneous sludge fermentation, denitrification and anammox. PMID:26874440

  13. Start-up of single-stage partial nitrification-anammox process treating low-strength swage and its restoration from nitrate accumulation.

    Science.gov (United States)

    Miao, Yuanyuan; Zhang, Liang; Yang, Yandong; Peng, Yongzhen; Li, Baikun; Wang, Shuying; Zhang, Qian

    2016-10-01

    A single-stage partial nitrification-anammox (PN/A) reactor treating low-strength swage was operated for 288days to investigate the recovery of nitrogen removal from nitrate accumulation. The reactor was quickly started up by inoculating anammox sludge. However, nitrite oxidizing bacteria (NOB) abundance gradually increased on day 25, leading to high effluent nitrate concentration. Two strategies were executed to control the effluent nitrate. In strategy I, dissolved oxygen (DO) concentration was kept low (0.17±0.08mg/L), but nitrate production increased from 4.71 to 38.18mg-N/L. In strategy II, intermittent aeration operation mode (aeration 7min/anoxic 21min) was adopted, which significantly lowered the nitrate concentration to 1.3mg-N/L, indicating the NOB was inhibited. The high nitrogen removal rate of 73mg-N/(L·d) was achieved. The evolution of bacterial activity and abundance verified the changes of the nitrogen removal performance and proved the intermittent aeration strategy could successfully solve the problem of nitrate build-up in the PN/A process. PMID:27423544

  14. Anaerobic digestion of cellulosic wastes

    International Nuclear Information System (INIS)

    Anaerobic digestion is a potentially attractive technology for volume reduction of low-level radioactive cellulosic wastes. A substantial fraction of the waste is converted to off-gas and a relatively small volume of biologically stabilized sludge is produced. Process development work has been completed using a 75-L digester to verify rates and conversions obtained at the bench scale. Start-up and operating procedures have been developed, and effluent was generated for characterization and disposal studies. Three runs using batch and fed-batch conditions were made lasting 36, 90, and 423 d. Solids solubilization rates and gas production rates averaged approximately 1.8 g cellulose per L of reactor per d and 1.2 L of off-gas per L reactor per d. Greater than 80% destruction of the volatile suspended solids was obtained. A simple dynamic process model was constructed to aid in process design and for use in process monitoring and control of a large-scale digester

  15. Anaerobic digestion of cellulosic wastes

    International Nuclear Information System (INIS)

    Anaerobic digestion is a potentially attractive technology for volume reduction of cellulosic wastes. A substantial fraction of the waste is converted to off-gas and a relatively small volume of biologically stabilized sludge is produced. Process development work is underway using a 75-L digester to verify rates and conversions obtained at the bench scale, to develop start-up and operating procedures, and to generate effluent for characterization and disposal studies. Three runs using batch and batch-fed conditions have been made lasting 36, 90, and over 200 days. Solids solubilization and gas production rates and total solids destruction have met or exceeded the target values of 0.6 g cellulose per L of reactor per day, 0.5 L off-gas per L of reactor per day, and 80% destruction of solids, respectively. Successful start-up procedures have been developed, and preliminary effluent characterization and disposal studies have been done. A simple dynamic process model has been constructed to aid in further process development and for use in process monitoring and control of a large-scale digester. 7 references, 5 figures, 1 table

  16. Anaerobic Nitrogen Fixers on Mars

    Science.gov (United States)

    Lewis, B. G.

    2000-07-01

    The conversion of atmospheric nitrogen gas to the protein of living systems is an amazing process of nature. The first step in the process is biological nitrogen fixation, the transformation of N2 to NH3. The phenomenon is crucial for feeding the billions of our species on Earth. On Mars, the same process may allow us to discover how life can adapt to a hostile environment, and render it habitable. Hostile environments also exist on Earth. For example, nothing grows in coal refuse piles due to the oxidation of pyrite and marcasite to sulfuric acid. Yet, when the acidity is neutralized, alfalfa and soybean plants develop root nodules typical of symbiotic nitrogen fixation with Rhizobium species possibly living in the pyritic material. When split open, these nodules exhibited the pinkish color of leghemoglobin, a protein in the nodule protecting the active nitrogen-fixing enzyme nitrogenase against the toxic effects of oxygen. Although we have not yet obtained direct evidence of nitrogenase activity in these nodules (reduction of acetylene to ethylene, for example), these findings suggested the possibility that nitrogen fixation was taking place in this hostile, non-soil material. This immediately raises the possibility that freeliving anaerobic bacteria which fix atmospheric nitrogen on Earth, could do the same on Mars.

  17. The effect of outside conditions on anaerobic ammonia oxidation reaction

    Institute of Scientific and Technical Information of China (English)

    YANG Min; WANG Shu-bo

    2016-01-01

    Organic carbon, inorganic carbon, temperature, pH and ORP are all to have a certain influence on the anaerobic ammonia oxidation reaction. We can draw some conclusions on the optimum conditions of anaerobic ammonia oxidation reaction. The optimum temperature of the anaerobic ammonia oxidation reaction is 30-35℃. And the optimum pH of the anaerobic ammonia reaction is 7.5-8.3. The presence of organic matters can affect the anaerobic ammonia reaction, and different organic matters have different influence on it. The concentration of the inorganic carbon also exist great influence on the reaction. High inorganic carbon concentration also can inhibit anaerobic ammonia oxidation reaction.

  18. Metabolic interactions between methanogenic consortia and anaerobic respiring bacteria

    DEFF Research Database (Denmark)

    Stams, A.J.; Oude Elferink, S.J.; Westermann, Peter

    2003-01-01

    Most types of anaerobic respiration are able to outcompete methanogenic consortia for common substrates if the respective electron acceptors are present in sufficient amounts. Furthermore, several products or intermediate compounds formed by anaerobic respiring bacteria are toxic to methanogenic...... consortia. Despite the potentially adverse effects, only few inorganic electron acceptors potentially utilizable for anaerobic respiration have been investigated with respect to negative interactions in anaerobic digesters. In this chapter we review competitive and inhibitory interactions between anaerobic...... respiring populations and methanogenic consortia in bioreactors. Due to the few studies in anaerobic digesters, many of our discussions are based upon studies of defined cultures or natural ecosystems...

  19. ANAEROBIC BIOLOGICAL TREATMENT OF PRODUCED WATER

    Energy Technology Data Exchange (ETDEWEB)

    John R. Gallagher

    2001-07-31

    During the production of oil and gas, large amounts of water are brought to the surface and must be disposed of in an environmentally sensitive manner. This is an especially difficult problem in offshore production facilities where space is a major constraint. The chief regulatory criterion for produced water is oil and grease. Most facilities have little trouble meeting this criterion using conventional oil-water separation technologies. However, some operations have significant amounts of naphthenic acids in the water that behave as oil and grease but are not well removed by conventional technologies. Aerobic biological treatment of naphthenic acids in simulated-produced water has been demonstrated by others; however, the system was easily overloaded by the large amounts of low-molecular-weight organic acids often found in produced waters. The objective of this research was to determine the ability of an anaerobic biological system to treat these organic acids in a simulated produced water and to examine the potential for biodegradation of the naphthenic acids in the anaerobic environment. A small fixed-film anaerobic biological reactor was constructed and adapted to treat a simulated produced water. The bioreactor was tubular, with a low-density porous glass packing material. The inocula to the reactor was sediment from a produced-water holding pond from a municipal anaerobic digester and two salt-loving methanogenic bacteria. During start-up, the feed to the reactor contained glucose as well as typical produced-water components. When glucose was used, rapid gas production was observed. However, when glucose was eliminated and the major organic component was acetate, little gas was generated. Methane production from acetate may have been inhibited by the high salt concentrations, by sulfide, or because of the lack, despite seeding, of microbes capable of converting acetate to methane. Toluene, a minor component of the produced water (0.1 g/L) was removed in the

  20. ANAEROBIC BIOLOGICAL TREATMENT OF PRODUCED WATER; TOPICAL

    International Nuclear Information System (INIS)

    During the production of oil and gas, large amounts of water are brought to the surface and must be disposed of in an environmentally sensitive manner. This is an especially difficult problem in offshore production facilities where space is a major constraint. The chief regulatory criterion for produced water is oil and grease. Most facilities have little trouble meeting this criterion using conventional oil-water separation technologies. However, some operations have significant amounts of naphthenic acids in the water that behave as oil and grease but are not well removed by conventional technologies. Aerobic biological treatment of naphthenic acids in simulated-produced water has been demonstrated by others; however, the system was easily overloaded by the large amounts of low-molecular-weight organic acids often found in produced waters. The objective of this research was to determine the ability of an anaerobic biological system to treat these organic acids in a simulated produced water and to examine the potential for biodegradation of the naphthenic acids in the anaerobic environment. A small fixed-film anaerobic biological reactor was constructed and adapted to treat a simulated produced water. The bioreactor was tubular, with a low-density porous glass packing material. The inocula to the reactor was sediment from a produced-water holding pond from a municipal anaerobic digester and two salt-loving methanogenic bacteria. During start-up, the feed to the reactor contained glucose as well as typical produced-water components. When glucose was used, rapid gas production was observed. However, when glucose was eliminated and the major organic component was acetate, little gas was generated. Methane production from acetate may have been inhibited by the high salt concentrations, by sulfide, or because of the lack, despite seeding, of microbes capable of converting acetate to methane. Toluene, a minor component of the produced water (0.1 g/L) was removed in the

  1. Control factors of partial nitritation for landfill leachate treatment

    Institute of Scientific and Technical Information of China (English)

    LIANG Zhu; LIU Jun-xin

    2007-01-01

    Anaerobic ammonium oxidation (ANAMMOX) technology has potential technical superiority and economical efficiency for the nitrogen removal from landfill leachate, which contains high-strength ammonium nitrogen (NH4+-N) and refractory organics. To complete the ANAMMOX process, a preceding partial nitritation step to produce the appropriate ratio of nitrite/ammonium is a key stage. The objective of this study was to determine the optimal conditions to acquire constant partial nitritation for landfill leachate treatment, and a bench scale fixed bed bio-film reactor was used in this study to investigate the effects of the running factors on the partial nitritation. The results showed that both the dissolved oxygen (DO) concentration and the ammonium volumetric loading rate (Nv) had effects on the partial nitritation. In the controlling conditions with a temperature of 30±1℃, Nv of 0.2-1.0 kg NH4+-N/(m3·d), and DO concentration of 0.8-2.3 mg/L, the steady partial nitritation was achieved as follows: more than 94% partial nitritation efficiency (nitrite as the main product), 60%-74% NH4+-N removal efficiency, and NO2--N/NH4+-N ratio (concentration ratio) of 1.0-1.4 in the effluent.The impact of temperature was related to Nv at certain DO concentration, and the temperature range of 25-30℃ was suitable for treating high strength ammonium leachate. Ammonium-oxidizing bacteria (AOB) could be acclimated to higher FA (free ammonium) in the range of 122-224 mg/L. According to the denaturing gradient gel electrophoresis analysis result of the bio-film in the reactor, there were 25 kinds of 16S rRNA gene fragments, which indicated that abundant microbial communities existed in the bio-film, although high concentrations of ammonium and FA may inhibit the growth of the nitrite-oxidizing bacteria (NOB) and other microorganisms in the reactor.

  2. Kinetics and modeling of anaerobic digestion process

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Angelidaki, Irini; Ahring, Birgitte Kiær

    Anaerobic digestion modeling started in the early 1970s when the need for design and efficient operation of anaerobic systems became evident. At that time not only was the knowledge about the complex process of anaerobic digestion inadequate but also there were computational limitations. Thus, the...... first models were very simple and consisted of a limited number of equations. During the past thirty years much research has been conducted on the peculiarities of the process and on the factors that influence it on the one hand while an enormous progress took place in computer science on the other. The...... combination of both parameters resulted in the development of more and more concise and complex models. In this chapter the most important models found in the literature are described starting from the simplest and oldest to the more recent and complex ones....

  3. [Anaerobic-aerobic infection in acute appendicitis].

    Science.gov (United States)

    Mamchich, V I; Ulitovskiĭ, I V; Savich, E I; Znamenskiĭ, V A; Beliaeva, O A

    1998-01-01

    362 patients with acute appendicitis (AA) were examined. For microbiological diagnosis of aerobic and anaerobic nonclostridial microflora we used complex accelerated methods (including evaluation of gram-negative microorganisms in comparison with tinctorial-fermentative method of differential staining according to oxygen sensitivity of catalasopositive together with aerobic and cathalasonegative anaerobic microorganisms) as well as complete bacteriologic examination with determination of sensitivity of the above microorganism to antimicrobial remedies. High rate of aerobic-anaerobic microbial associations and substantial identity of microflora from appendicis and exudate from abdominal cavity was revealed, which evidenced the leading role of endogenous microorganisms in etiology and pathogenesis of AA and peritonitis i. e. autoinfection. In patients with destructive forms of AA, complicated by peritonitis it is recommended to use the accelerated method of examination of pathologic material as well as the complete scheme of examination with the identification of the isolated microorganisms and the correction of antibiotic treatment. PMID:9511291

  4. Anaerobic lipid degradation through acidification and methanization.

    Science.gov (United States)

    Kim, Ijung; Kim, Sang-Hyoun; Shin, Hang-Sik; Jung, Jin-Young

    2010-01-01

    In biological wastewater treatment high lipid concentration is known to inhibit microorganisms and cause active biomass flotation. To reduce lipid inhibition, a two-phase anaerobic system, consisting of an anaerobic sequencing batch reactor (ASBR) and an upflow anaerobic sludge blanket (UASB) reactor, was applied to synthetic dairy wastewater. During 153 days of operation, the two-phase system showed stable performance in lipid degradation. In the ASBR, a 13% lipid removal efficiency and 10% double bond removal efficiency were maintained. In the UASB, the chemical oxygen demand (COD), lipid and volatile fatty acid (VFA) removal efficiencies were more than 80%, 70% and 95%, respectively, up to organic loading rate 6.5 g COD/L/day. There were no operational problems such as serious scum formation or sludge washout. Protein degradation occurred prior to degradation during acidogenesis. PMID:20134250

  5. Biochemistry and physiology of anaerobic bacteria

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-05-18

    We welcome you to The Power of Anaerobes. This conference serves two purposes. One is to celebrate the life of Harry D. Peck, Jr.,who was born May 18, 1927 and would have celebrated his 73rd birthday at this conference. He died November 20, 1998. The second is to gather investigators to exchange views within the realm of anaerobic microbiology, an area in which tremendous progress has been seen during recent years. It is sufficient to mention discoveries of a new form of life (the archaea), hyper or extreme thermophiles, thermophilic alkaliphiles and anaerobic fungi. With these discoveries has come a new realization about physiological and metabolic properties of microorganisms, and this in turn has demonstrated their importance for the development, maintenance and sustenance of life on Earth.

  6. Biochar from anaerobically digested sugarcane bagasse.

    Science.gov (United States)

    Inyang, Mandu; Gao, Bin; Pullammanappallil, Pratap; Ding, Wenchuan; Zimmerman, Andrew R

    2010-11-01

    This study was designed to investigate the effect of anaerobic digestion on biochar produced from sugarcane bagasse. Sugarcane bagasse was anaerobically digested to produce methane. The digested residue and fresh bagasse was pyrolyzed separately into biochar at 600 degrees C in nitrogen environment. The digested bagasse biochar (DBC) and undigested bagasse biochar (BC) were characterized to determine their physicochemical properties. Although biochar was produced from the digested residue (18% by weight) and the raw bagasse (23%) at a similar rate, there were many physiochemical differences between them. Compared to BC, DBC had higher pH, surface area, cation exchange capacity (CEC), anion exchange capacity (AEC), hydrophobicity and more negative surface charge, all properties that are generally desirable for soil amelioration, contaminant remediation or wastewater treatment. Thus, these results suggest that the pyrolysis of anaerobic digestion residues to produce biochar may be an economically and environmentally beneficial use of agricultural wastes. PMID:20634061

  7. The effect of tannic compounds on anaerobic wastewater treatment.

    NARCIS (Netherlands)

    Field, J.A.

    1989-01-01

    Anaerobic wastewater treatment is an alternative to the conventional aerobic treatment processes for the removal of easily biodegradable organic matter in medium to high strength industrial wastestreams. Anaerobic treatment has several advantages, however one important disadvantage is the high sensi

  8. ANAEROBIC AND AEROBIC TREATMENT OF CHLORINATED ALIPHATIC COMPOUNDS

    Science.gov (United States)

    Biological degradation of 12 chlorinated aliphatic compounds (CACs) was assessed in bench-top reactors and in serum bottle tests. Three continuously mixed daily batch-fed reactor systems were evaluated: anaerobic, aerobic, and sequential-anaerobic-aerobic (sequential). Glucose,...

  9. Succession of lignocellulolytic bacterial consortia bred anaerobically from lake sediment

    NARCIS (Netherlands)

    Korenblum, Elisa; Jiménez Avella, Diego; van Elsas, Jan

    2016-01-01

    Anaerobic bacteria degrade lignocellulose in various anoxic and organically rich environments, often in a syntrophic process. Anaerobic enrichments of bacterial communities on a recalcitrant lignocellulose source were studied combining polymerase chain reaction–denaturing gradient gel electrophoresi

  10. Multivariate monitoring of anaerobic co-digestion

    DEFF Research Database (Denmark)

    Madsen, Michael; Holm-Nielsen, Jens Bo

    warming and environmental concerns. Anaerobic digestion applied in agriculture can simultaneously convert heterogeneous biomasses and wastes from the primary agricultural sector and from the bio processing industries, for instance food processing, pharma, and biofuel production, into valuable organic...... fertiliser and renewable energy. Meanwhile, in order for the biogas sector to become a significant player in the energy supply chain, the anaerobic digestion process has to be controlled to a greater extent than what is implemented as state-of-the-art today. Through application of the philosophy behind...

  11. Susceptibility of anaerobic bacteria to carbenicillin.

    Science.gov (United States)

    Blazevic, D J; Matsen, J M

    1974-05-01

    One hundred and seventy-one strains of anaerobes were tested for susceptibility to carbenicillin by using agar dilution, broth dilution, and two disk diffusion methods. The minimal inhibitory concentration (MIC) for 67% of 51 strains of Bacteroides fragilis, 7 of 9 strains of Bacteroides melaninogenicus, and all of 8 strains of Eubacterium was 100 mug or less per ml. The MICs of the remaining anaerobes were 50 mug or less per ml. The broth dilution results were felt to be the most accurate of the four methods utilized. PMID:4462461

  12. Startup and stabilization of anaerobic membrane bioreactors at ambient temperature

    OpenAIRE

    Benito Peña, Carlos

    2015-01-01

    There has been an increasing interest in wastewater treatment in last decades to reduce human footprint. Primarily, anaerobic technology focused on treatment and stabilization of sludge, but now the tendency is to give it a major role in low cost treatment of high/low strength wastewaters, since anaerobic digestion offers energy generation through gas production. Anaerobic membrane bioreactors (AnMBR) combine anaerobic digestion with membrane filtration. They are becoming a feasible opti...

  13. The Financial Feasibility of Anaerobic Digestion for Ontario's Livestock Industries

    OpenAIRE

    Weersink, Alfons; Mallon, Shawn

    2007-01-01

    This report is an investigation of the financial feasibility of farm based anaerobic digestion investments under Ontario's Standard Offer Contract electricity prices. Using Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) Agricultural Anaerobic Digestion Calculation Spreadsheet (AADCS) anaerobic digestion inputs, outputs, cost and revenues were estimated and used to conduct a financial analysis on the feasibility of four sized farm base anaerobic digestion investments. The res...

  14. The effect of tannic compounds on anaerobic wastewater treatment.

    OpenAIRE

    Field, J. A.

    1989-01-01

    Anaerobic wastewater treatment is an alternative to the conventional aerobic treatment processes for the removal of easily biodegradable organic matter in medium to high strength industrial wastestreams. Anaerobic treatment has several advantages, however one important disadvantage is the high sensitivity of the anaerobic bacteria (ie. methanogenic bacteria) to toxic compounds. The anaerobic technologies were initially developed for the treatment of non-toxic organic wastewaters. As the techn...

  15. Treatment of domestic sewage in a two-step system anaerobic filter/anaerobic hybrid reactor at low temperature

    NARCIS (Netherlands)

    Elmitwalli, T.A.; Zeeman, G.; Oahn, K.L.T.; Lettinga, G.

    2002-01-01

    The treatment of domestic sewage at low temperature of 13 degrees Celsius was investigated in a two-step system consisting of an anaerobic filter (AF) + an anaerobic hybrid (AH) reactor operated at different hydraulic retention times (HRTs)

  16. The IWA Anaerobic digestion model no 1. (ADM1)

    DEFF Research Database (Denmark)

    Batstone, Damien J.; Keller, J.; Angelidaki, Irini;

    2002-01-01

    The IWA Anaerobic Digestion Modelling Task Group was established in 1997 at the 8th World Congress on Anaerobic Digestion (Sendai, Japan) with the goal of developing a generalised anaerobic digestion model. The structured model includes multiple steps describing biochemical as well...

  17. Stability of anaerobic reactors under micro-aeration conditions

    International Nuclear Information System (INIS)

    Oxidation of sulphide in anaerobic bioreactors by introducing limited amounts of oxygen provides a relatively simple strategy for reducing the levels of sulphite in anaerobic digesters (biogas and effluent). The introduction of limited amounts of air is a general practice in agricultural anaerobic digesters, it is estimated that worldwide over 3.000 units are operated under such conditions. (Author)

  18. Anaerobic Digestion. Student Manual. Biological Treatment Process Control.

    Science.gov (United States)

    Carnegie, John W., Ed.

    This student manual contains the textual material for a four-lesson unit on anaerobic digestion control. Areas addressed include: (1) anaerobic sludge digestion (considering the nature of raw sludge, purposes of anaerobic digestion, the results of digestion, types of equipment, and other topics); (2) digester process control (considering feeding…

  19. Proceedings of the 10. world congress on anaerobic digestion 2004 : anaerobic bioconversion, answer for sustainability

    International Nuclear Information System (INIS)

    This conference reviewed the broad scope of anaerobic process-related activities taking place globally and confirmed the possibilities of using anaerobic processes to add value to industrial wastewaters, municipal solid wastes and organic wastes while minimizing pollution and greenhouse gases. It focused on biomolecular tools, instrumentation of anaerobic digestion processes, anaerobic bioremediation of chlorinated organics, and thermophilic and mesophilic digestion. Several papers focused on the feasibility of using waste products to produce hydrogen and methane for electricity generation. The sessions of the conference were entitled acidogenesis; microbial ecology; process control; sulfur content; technical development; domestic wastewater; agricultural waste; organic municipal solid wastes; instrumentation; molecular biology; sludges; agricultural feedstock; bioremediation; industrial wastewater; hydrogen production; pretreatments; sustainability; and integrated systems. The conference featured 387 posters and 192 oral presentations, of which 111 have been indexed separately for inclusion in this database. refs., tabs., figs

  20. Environmental impacts of anaerobic digestion and the use of anaerobic residues as soil amendment

    Energy Technology Data Exchange (ETDEWEB)

    Mosey, F.E. [VFA Services Ltd., Herts (United Kingdom)

    1996-01-01

    This paper defines the environmental role of anaerobic digestion within the overall objective of recovering energy from renewable biomass resources. Examples and opportunities for incorporating anaerobic digestion into biomass-to-energy schemes are discussed, together with environmental aspects of anaerobic digestion plants. These include visual, public amenity, pathogens and public health, odor control, and gaseous emissions. Digestate disposal and the benefits of restrictions on recycling organic wastes and biomass residues back to the land are discussed, particularly as they relate to American and European codes of practice and environmental legislation. The paper concludes that anaerobic digestion, if performed in purpose-designed reactors that efficiently recover and use biogas, is an environmentally benign process that can enhance energy recovery and aid the beneficial land use of plant residues in many biomass-to-energy schemes.

  1. Biological treatment of nitrogen-rich refinery wastewater by partial nitritation (SHARON) process.

    Science.gov (United States)

    Milia, S; Cappai, G; Perra, M; Carucci, A

    2012-01-01

    Wastewater discharges containing high nitrogen levels can be toxic to aquatic life and cause eutrophication. In this study, the application of the SHARON (Single reactor for High activity Ammonium Removal Over Nitrite) process for the treatment of refinery wastewater (sour water) was evaluated, in view of its coupling with the ANAMMOX (ANaerobic AMMonium OXidation) process. A Continuous Flow Stirred Tank Reactor was initially fed with a synthetic medium, and the applied NH4-N concentration and wastewater/synthetic medium ratio were progressively increased up to 2000 mgN/L and 100%, respectively. Despite the high potential toxic effect of the real wastewater, overall SHARON performance did not decrease with the increasing real wastewater/synthetic medium ratio, and biomass showed progressive acclimation to the toxic compounds in the real wastewater, as demonstrated by toxicity assessments. NH4-N and dissolved organic carbon removal efficiency were around 50% and 65%, respectively. Moreover, the effluent was characterized by a NO2-N/NH4-N ratio of 0.9 +/- 0.01 and low nitrate concentration (<30 mgN/L), in line with the requirements for the subsequent treatment by the ANAMMOX process. PMID:22988604

  2. Metaproteomics reveals differential modes of metabolic coupling among ubiquitous oxygen minimum zone microbes

    Energy Technology Data Exchange (ETDEWEB)

    Hawley, Alyse K.; Brewer, Heather M.; Norbeck, Angela D.; Pasa-Tolic, Ljiljana; Hallam, Steven J.

    2014-08-05

    Oxygen minimum zones (OMZs) are intrinsic water column features arising from respiratory oxygen demand during organic matter degradation in stratified marine waters. Currently OMZs are expanding due to global climate change. This expansion alters marine ecosystem function and the productivity of fisheries due to habitat compression and changes in biogeochemical cycling leading to fixed nitrogen loss and greenhouse gas production. Here we use metaproteomics to chart spatial and temporal patterns of gene expression along defined redox gradients in a seasonally anoxic fjord, Saanich Inlet to better understand microbial community responses to OMZ expansion. The expression of metabolic pathway components for nitrification, anaerobic ammonium oxidation (anammox), denitrification and inorganic carbon fixation predominantly co-varied with abundance and distribution patterns of Thaumarchaeota, Nitrospira, Planctomycetes and SUP05/ARCTIC96BD-19 Gammaproteobacteria. Within these groups, pathways mediating inorganic carbon fixation and nitrogen and sulfur transformations were differentially expressed across the redoxcline. Nitrification and inorganic carbon fixation pathways affiliated with Thaumarchaeota dominated dysoxic waters and denitrification, sulfur-oxidation and inorganic carbon fixation pathways affiliated with SUP05 dominated suboxic and anoxic waters. Nitrite-oxidation and anammox pathways affiliated with Nitrospina and Planctomycetes respectively, also exhibited redox partitioning between dysoxic and suboxic waters. The differential expression of these pathways under changing water column redox conditions has quantitative implications for coupled biogeochemical cycling linking different modes of inorganic carbon fixation with distributed nitrogen and sulfur-based energy metabolism extensible to coastal and open ocean OMZs.

  3. Dissimilatory nitrate reduction to ammonium conserves nitrogen in anthropogenically affected subtropical mangrove sediments in Southeast China.

    Science.gov (United States)

    Cao, Wenzhi; Yang, Jingxin; Li, Ying; Liu, Baoli; Wang, Feifei; Chang, Changtang

    2016-09-15

    In this study, basic sediment properties, nutrient flux, and nitrogen cycle (including denitrification, anaerobic ammonium oxidation [anammox], nitrification, and dissimilatory nitrate reduction to ammonium [DNRA]) were investigated at two sampling sites with different tree ages in the mangrove region of the Jiulong River Estuary, China. The results show that sediments at mangrove flat area have relatively strong capability to reduce NO3(-), in which the DNRA rate is relatively high (204.53±48.32μmolNm(-2)h(-1)), which is approximately 75.7-85.9% of the total NO3(-) reduction, while the denitrification and anammox rates are relatively low - only approximately 5.6-9.5% and 8.5-14.8% of the total NO3(-) reduction, respectively. Thus, in the nitrogen-enriched subtropical mangrove system, DNRA is the main pathway to reduce NO3(-), and most of the input nitrogen is conserved as NH4(+) in the system, which assures high productivity of the mangrove system. PMID:27368926

  4. Mechanism studies on nitrogen removal when treating ammonium-rich leachate by sequencing batch biofilm reactor

    Institute of Scientific and Technical Information of China (English)

    XU Zhengyong; YANG Zhaohui; ZENG Guangming; XIAO Yong; DENG Jiuhua

    2007-01-01

    The nitrogen removal mechanism was studied and analyzed when treating the ammonium-rich landfill leachate by a set of sequencing batch biofilm reactors(SBBRs),which was designed independently.At the liquid temperature of(32±0.4)℃,and after a 58-days domestication period and a 33-days stabilization period.the efficiency of ammonium removal in the SBBR went up to 95%.Highly frequent intermittent aeration suppressed the activity of nitratebacteria.and also eliminated the influence on the activity of anaerobic ammonium oxidation(ANAMMOX)bacteria and nitritebacteria.This influence was caused by the accumulation of nitrous acid and the undulation of pH.During the aeration stage,the concentration of dissolved oxygen was controlled at 1.2-1.4 mg/L.The nitritebacteria became dominant and nitrite accumulated gradually.During the anoxic stage,along with the concentration debasement of the dissolved oxygen,ANAMMOX bacteria became dominant;then,the nitrite that was accumulated in the aeration stage was wiped off with ammonium simultaneously.

  5. A simple and sensitive quality control method of the anaerobic atmosphere for identification and antimicrobial susceptibility testing of anaerobic bacteria

    DEFF Research Database (Denmark)

    Justesen, Tage; Justesen, Ulrik Stenz

    2013-01-01

    The maintenance of a strict anaerobic atmosphere is essential for the culture of strict anaerobic bacteria. We describe a simple and sensitive quality control method of the anaerobic atmosphere, based on the measurement of the zone diameter around a 5-μg metronidazole disk when testing an...

  6. Investigating the role of co-substrate-substrate ratio and filter media on the performance of anammox hybrid reactor treating nitrogen rich wastewater.

    Science.gov (United States)

    Tomar, Swati; Gupta, Sunil Kumar

    2016-03-01

    This study explored the feasibility of using the anammox hybrid reactor (AHR), which combines suspended and attached growth media, for the biodegradation of ammonical nitrogen in wastewater. The study was performed in four laboratory-scale AHRs, inoculated with mixed seed culture (1:1). The anammox process was established by feeding the AHR with synthetic wastewater, containing NH(4)-N and NO(2)-N (1:1), at hydraulic retention time (HRT) of 1 day. The reactors were gradually acclimated to a higher ammonium concentration (1200 mg/l) until the pseudo-steady state was attained. Subsequently, the reactors were operated at various HRTs (0.25-3.0 days) to optimize the HRT and nitrogen loading rate (NLR). The study demonstrated that HRT of 1 day, corresponding to 95.1% of nitrogen removal was optimal. Pearson correlation analysis indicated the strong and positive correlation of HRT and sludge retention time (SRT), whereas the NLR and biomass yield correlated negatively with the nitrogen removal efficiency (NRE). The mass balance of nitrogen showed that a major fraction (79.1%) of the input nitrogen was converted into N2 gas, and 11.25% was utilized in synthesizing the biomass. The filter media in the AHR contributed to an additional 15.4% of ammonium removal and a reduction of 29% in the sludge washout rate. The nitrogen removal kinetics in the AHR followed the modified Stover-Kincannon model, whereas the Lawrence-McCarty model best described the bacterial growth kinetics. The study concludes that the hybrid configuration of the reactor demonstrated promising results and could be suitably applied for industrial applications. PMID:26277220

  7. A new mathematical model for nitrogen gas production with special emphasis on the role of attached growth media in anammox hybrid reactor.

    Science.gov (United States)

    Tomar, Swati; Gupta, Sunil Kumar

    2015-11-01

    The present study emphasised on the development of new mathematical models based on mass balance and stoichiometry of nitrogen removal in anammox hybrid reactor (AHR). The performance of AHR at varying hydraulic retention times (HRTs) and nitrogen loading rates (NLRs) revealed that nitrogen removal efficiency (NRE) increases with increase in HRT and was found optimal (89 %) at HRT of 2 days. Mass balance of nitrogen revealed that major fraction (74.1 %) of input nitrogen is converted into N2 gas followed by 11.2 % utilised in biomass synthesis. Attached growth media (AGM) in AHR contributed to an additional 15.4 % ammonium removal and reduced the sludge washout rate by 29 %. This also enhanced the sludge retention capacity of AHR and thus minimised the formation of nitrate in the treated effluent, which is one of the bottlenecks of anammox process. Process kinetics was also studied using various mathematical models. The mass balance model derived from total nitrogen was found most precise and predicted N2 gas with least error (1.68 ± 4.44 %). Model validation for substrate removal kinetics dictated comparatively higher correlation for Grau second-order model (0.952) than modified Stover-Kincannon model (0.920). The study concluded that owing to features of high biomass retention, less nitrate formation and consistently higher nitrogen removal efficiency, this reactor configuration is techno-economically most efficient and viable. The study opens the door for researchers and scientists for pilot-scale testing of AHR leading to its wide industrial application. PMID:26143610

  8. Anaerobic membrane bioreactors: Are membranes really necessary?

    NARCIS (Netherlands)

    Davila, M.; Kassab, G.; Klapwijk, A.; Lier, van J.B.

    2008-01-01

    Membranes themselves represent a significant cost for the full scale application of anaerobic membrane bioreactors (AnMBR). The possibility of operating an AnMBR with a self-forming dynamic membrane generated by the substances present in the reactor liquor would translate into an important saving. A

  9. Applications of the anaerobic digestion process

    DEFF Research Database (Denmark)

    Angelidaki, Irini; Ellegaard, L.; Ahring, Birgitte Kiær

    2003-01-01

    and resource/energy recovery have been developed. Treatment of biowastes by anaerobic digestion processes is in many cases the optimal way to convert organic waste into useful products such as energy (in the form of biogas) and a fertilizer product. Other waste management options, such as land filling...

  10. Analysis of denitrification in swine anaerobic lagoons

    Science.gov (United States)

    Anaerobic lagoons are a common management practice for the treatment of swine wastewater. Although these lagoons were once thought to be relatively simple; their physical, chemical, and biological processes are actually very sophisticated. To get a better understanding of the processes which occur i...

  11. Anaerobic work capacity in elite wheelchair athletes

    NARCIS (Netherlands)

    van der Woude, L H; Bakker, W H; Elkhuizen, J W; Veeger, DirkJan (H. E. J.); Gwinn, T

    1997-01-01

    To study the anaerobic work capacity in wheelchair athletes, 67 elite wheelchair athletes (50 male) were studied in a 30-second sprint test on a computer-controlled wheelchair ergometer during the World Championships and Games for the Disabled in Assen (1990). The experimental set-up (ergometer, pro

  12. Anaerobic effluent disinfection using ozone: Byproducts formation

    NARCIS (Netherlands)

    Silva, G.H.R.; Daniel, L.A.; Bruning, H.; Rulkens, W.H.

    2010-01-01

    This research was aimed at studying oxidation processes, coliform inactivation effectiveness and disinfection byproducts (DBPs) associated with the disinfection of anaerobic sanitary wastewater effluent with ozone applied at doses of 5.0, 8.0 and 10.0mg O(3)L(-1) for contact times of 5, 10 and 15 mi

  13. Anaerobic hydrolysis during digestion of complex substrates

    NARCIS (Netherlands)

    Sanders, W.T.M.

    2001-01-01

    Complex waste(water) such as, raw sewage, dairy wastewater, slaughterhouse wastewater, fish processing wastewater, primary sludge and the organic fraction of municipal solid waste have been proven to be degradable under anaerobic conditions. However, during the digestion process the conversion of th

  14. Sulfate-reducing bacteria in anaerobic bioreactors.

    NARCIS (Netherlands)

    Oude Elferink, S.J.W.H.

    1998-01-01

    The treatment of industrial wastewaters containing high amounts of easily degradable organic compounds in anaerobic bioreactors is a well-established process. Similarly, wastewaters which in addition to organic compounds also contain sulfate can be treated in this way. For a long time, the occurrenc

  15. Anaerobic digestion in sustainable biomass chains

    NARCIS (Netherlands)

    Pabon Pereira, C.P.

    2009-01-01

    This thesis evaluates the potential contribution of anaerobic digestion (AD) to the sustainability of biomass chains. Results provide insights in the technological potential to recover energy and valuable by-products from energy crops and residues, and evaluate biomass cascades involving AD technolo

  16. Anaerobic digestion of slaughterhouse by-products

    DEFF Research Database (Denmark)

    Hejnfelt, Anette; Angelidaki, Irini

    2009-01-01

    Anaerobic digestion of animal by-products was investigated in batch and semi-continuously fed, reactor experiments at 55 degrees C and for some experiments also at 37 degrees C. Separate or mixed by-products from pigs were tested. The methane potential measured by batch assays for meat- and bone...

  17. Can Anaerobic Fungi Improve Biogas Production?

    Czech Academy of Sciences Publication Activity Database

    Fliegerová, Kateřina; Mrázek, Jakub; Štrosová, Lenka; Procházka, J.

    Edinburgh : Elsevier, 2010. s. 1-1. [IMC9 (9th International mycological congress): The biology of Fungi. 01.08.2010 - 06.08.2010, Edinburgh] Institutional research plan: CEZ:AV0Z50450515 Keywords : anaerobic fungi * biogas production Subject RIV: EH - Ecology, Behaviour

  18. Biodegradability of leathers through anaerobic pathway.

    Science.gov (United States)

    Dhayalan, K; Fathima, N Nishad; Gnanamani, A; Rao, J Raghava; Nair, B Unni; Ramasami, T

    2007-01-01

    Leather processing generates huge amounts of both solid and liquid wastes. The management of solid wastes, especially tanned leather waste, is a challenging problem faced by tanners. Hence, studies on biodegradability of leather become imperative. In this present work, biodegradability of untanned, chrome tanned and vegetable tanned leather under anaerobic conditions has been addressed. Two different sources of anaerobes have been used for this purpose. The effect of detanning as a pretreatment method before subjecting the leather to biodegradation has also been studied. It has been found that vegetable tanned leather leads to more gas production than chrome tanned leather. Mixed anaerobic isolates when employed as an inoculum are able to degrade the soluble organics of vegetable tanned material and thus exhibit an increased level of gas production during the initial days, compared to the results of the treatments that received the anaerobic sludge. With chrome tanned materials, there was not much change in the volume of the gas produced from the two different sources. It has been found that detanning tends to improve the biodegradability of both types of leathers. PMID:16740383

  19. Enrichment of denitrifying anaerobic methane oxidizing microorganisms.

    Science.gov (United States)

    Hu, Shihu; Zeng, Raymond J; Burow, Luke C; Lant, Paul; Keller, Jurg; Yuan, Zhiguo

    2009-10-01

    The microorganisms responsible for anaerobic oxidation of methane (AOM) coupled to denitrification have not been clearly elucidated. Three recent publications suggested it can be achieved by a denitrifying bacterium with or without the involvement of anaerobic methanotrophic archaea. A key factor limiting the progress in this research field is the shortage of enrichment cultures performing denitrifying anaerobic methane oxidation (DAMO). In this study, DAMO cultures were enriched from mixed inoculum including sediment from a freshwater lake, anaerobic digester sludge and return activated sludge from a sewage treatment plant. Two reactors, operated at 35°C and at 22°C, respectively, showed simultaneous methane oxidation and nitrate reduction after several months of operation. Analysis of 16S rRNA gene clone libraries from the 35°C enrichment showed the presence of an archaeon closely related to other DAMO archaea and a dominated bacterium belonging to the yet uncultivated NC10 phylum. This culture preferred nitrite to nitrate as the electron acceptor. The present study suggests that the archaea are rather methanotrophs than methanogens. The highest denitrification rate achieved was 2.35 mmol NO3 (-) -N gVSS(-1)  day(-1) . The culture enriched at 22°C contained the same NC10 bacterium observed in the culture enriched at 35°C but no archaea. PMID:23765890

  20. Anaerobic Toxicity of Cationic Silver Nanoparticles

    Science.gov (United States)

    The microbial toxicity of silver nanoparticles (AgNPs) stabilized with different capping agents was compared to that of Ag+ under anaerobic conditions. Three AgNPs were investigated: (1) negatively charged citrate-coated AgNPs (citrate-AgNPs), (2) minimally charged p...

  1. Anaerobic Digestion of Paper Mill Wastewater

    Directory of Open Access Journals (Sweden)

    Shreeshivadasan Chelliapan

    2012-01-01

    Full Text Available In general, paper mill wastewater contains complex organic substances which could not be treated completely using conventional treatment processes, e.g. aerobic processes. As a result, anaerobic technology is a promising alternative for paper mill wastewater treatment due to its ability to degrade hard organic compounds. In the present study, treatment of paper mill wastewater using a stage anaerobic reactor was investigated. The more specific objectives of this study were to confirm whether paper mill wastewater can be tolerated by methanogenic sludge and to assess the stability of reactor for measured parameters (e.g. COD removal, and methane composition. Results showed up to 98% COD removal efficiency in the anaerobic reactor when the reactor was operated at an OLR of 1.560 kg COD/m3.d. Anaerobic digestion can provide high treatment efficiency for recalcitrant substrates, which generates robust microorganism (acidogenesis and methanogenesis, for the degradation of recalcitrant compounds such as in the paper mill wastewater.

  2. Anaerobic Digestion: Mass Balances and Products

    DEFF Research Database (Denmark)

    Møller, Jacob; Christensen, Thomas Højlund; Jansen, Jes la Cour

    2011-01-01

    While the basic processes involved in anaerobic digestion of waste are described in Chapter 9.4 and the main digestion technologies are presented in Chapter 9.5, this chapter focuses on mass balances, gas production and energy aspects, environmental emissions and unit process inventories...

  3. Anaerobic Digestion in a Flooded Densified Leachbed

    Science.gov (United States)

    Chynoweth, David P.; Teixeira, Arthur A.; Owens, John M.; Haley, Patrick J.

    2009-01-01

    A document discusses the adaptation of a patented biomass-digesting process, denoted sequential batch anaerobic composting (SEBAC), to recycling of wastes aboard a spacecraft. In SEBAC, high-solids-content biomass wastes are converted into methane, carbon dioxide, and compost.

  4. Comparative activity of ciprofloxacin against anaerobic bacteria.

    OpenAIRE

    Sutter, V L; Kwok, Y Y; Bulkacz, J

    1985-01-01

    The in vitro activity of ciprofloxacin was assessed against 362 strains of anaerobic bacteria and compared with that of cefoxitin, clindamycin, metronidazole, and mezlocillin. Only 31% of the strains tested were susceptible to ciprofloxacin. The other agents were active against most of the strains tested.

  5. Pectinase Activity of Anaerobic and Facultatively Anaerobic Bacteria Associated with Soft Rot of Yam (Diascorea rotundata)

    OpenAIRE

    Obi, Samuel K. C.

    1981-01-01

    Anaerobic and facultatively anaerobic bacteria associated with soft rot of yam (Diascorea rotundata) were isolated by the looping-out method and found to consist of Clostridium (three isolates), Corynebacterium (three isolates), Vibrio (one isolate), and Bacillus lentus (one isolate). Enzyme assay for hydrolase, lyase, and pectinesterase activities by the cup-plate method showed that except for Vibrio sp., B. lentus, and two isolates of Corynebacterium no pectinase activity could be detected ...

  6. Stable isotope fractionation related to microbial nitrogen turnover in constructed wetlands treating contaminated groundwater

    Science.gov (United States)

    Voloshchenko, O.; Knoeller, K.

    2013-12-01

    To improve the efficiency of ground- and wastewater treatment in constructed wetlands (CWs), better understanding of the occurring processes is necessary. This research explores N-isotope fractionations associated with the removal of ammonium from contaminated groundwater in pilot-scale CWs downstream of the chemical industrial area Leuna, Germany. The groundwater at the site is contaminated mainly by organic (BTEX, MTBE) and inorganic compounds (ammonium). We assume that the anaerobic ammonium oxidation (ANAMMOX) plays an important role in nitrogen removal in these CWs. However, to date, interactions between processes of aerobic and anaerobic ammonium oxidation in CWs still have not been well explored. Especially, the importance of the ANAMMOX process for the nitrogen removal is generally accepted, but its role in CWs is quite unknown. For this aim, three CWs were chosen: planted horizontal subsurface flow (HSSF); unplanted HSSF, and floating plant root mat (FPRM). Water samples were taken at the inflow and outflow as well as from the pore space at different distances (1, 2.5 and 4 m) from the inlet and at different depths (20, 30 and 40 cm in the HSSF-CWs, 30 cm in the FPRM). Samples were collected in a time interval of 1 to 6 weeks during 1 year with the exception of the winter season. Physicochemical parameters, nitrogen isotope signatures of ammonium, as well as nitrogen and oxygen isotope signatures of nitrate were analysed. Within the CWs, spatial concentration gradients of the nitrogen species (ammonium and nitrate) are observed. N-isotope variations of ammonium and nitrate are interpreted according to the prevailing processes of the N-transformations. Based on isotope mass-balance approach microbial processes such as nitrification, denitrification, and ANAMMOX are quantified. DNA from biofilms at roots and gravel was extracted using FastDNA Spin Kit For Soil (MP Biomedicals). PCR, quantitative PCR, cloning, and sequencing were applied with the purpose of

  7. Innovative microbial fuel cell for electricity production from anaerobic reactors

    DEFF Research Database (Denmark)

    Min, Booki; Angelidaki, Irini

    2008-01-01

    A submersible microbial fuel cell (SMFC) was developed by immersing an anode electrode and a cathode chamber in an anaerobic reactor. Domestic wastewater was used as the medium and the inoculum in the experiments. The SMFC could successfully generate a stable voltage of 0.428 ± 0.003 V with a fixed...... for electricity production from existing anaerobic reactors or other anaerobic environments such as sediments. The advantage of the SMFC is that no special anaerobic chamber (anode chamber) is needed, as existing anaerobic reactors can be used, where the cathode chamber and anode electrode are immersed....

  8. ISOLATION OF ANAEROBES IN DEEP SEATED PRESSURE ULCERS USING A NOVEL INNOVATIVE TECHNIQUE OF ANAEROBE ISOLATION

    Directory of Open Access Journals (Sweden)

    Lalbiaktluangi

    2015-12-01

    Full Text Available BACKGROUND Isolation of an anaerobe is usually neglected in hospitals with limited resources due to the expensive and complicated technique of anaerobic isolation methods, which is difficult to arrange in such resource poor settings. Conventionally adopted anaerobic culture methods such as Anaerobic jar, Gas-Pak, Anoxomat or Automated glove-box systems are extremely costly and cumbersome for single unit testing, but not suitable for small scale laboratories. However, anaerobic bacteria are not to be overlooked as they have made a comeback in clinical settings and are even showing resistance to Metronidazole, once thought to be the gold standard bullet against anaerobes. Deep seated pressure ulcers are usually the site where anaerobe causes an infection in synergy with aerobes. AIMS AND OBJECTIVES Isolation of anaerobes in deep seated pressure ulcers using a novel innovative technique and to study their antibiogram profile. MATERIALS AND METHODS Swabs taken from depth of deep seated pressure ulcers were immediately inoculated in Brucella blood agar at bedside and placed in polycarbonate airtight jar for anaerobic incubation using a novel innovative Modified Candle Jar technique. In this technique five grams of grease-free grade zero steel wool were dipped in 50ml freshly prepared acidified copper sulphate solution until the copper colour appeared. Excess solution was drained and the steel wool was moulded into a loose pad to fit on an open Petri plate placed on top of the inoculated Brucella blood agar plates. A white-wax candle was placed at the centre of this plate. A small test tube containing mixture of 0.5g sodium-bicarbonate and 0.5g magnesium carbonate was kept ready to be placed inside the jar, just after placing the inoculated plate and incubated for 48 hours. RESULTS Peptostreptococcus anaerobius and Bacteroides fragilis were successfully isolated from deep seated pressure ulcers by this method. Antibiogram studies were done using the

  9. Instrumentation and Control in Anaerobic Digestion

    DEFF Research Database (Denmark)

    Anaerobic digestion is a multistep process, and is most applied to solids destruction and wastewater treatment for energy production. Despite wide application, and long-term industrial proof of application, some industries are still reluctant to apply this technology. One of the classical reasons...... benchmark. There has therefore been, overall, a quantum advance in application and sophistication of instrumentation and control in anaerobic digestion, and it is an effective option for improved process loading rate and conversion efficiency....... are still a limitation, but this is being partly addressed by the increased complexity of digestion processes. Methods for control benchmarking have also been improved, as there is now an industry standard model (the IWA ADM1), and this is being applied in an improved whole wastewater treatment plant...

  10. Robust regulation of anaerobic digestion processes.

    Science.gov (United States)

    Mailleret, L; Bernard, O; Steyer, J P

    2003-01-01

    This paper deals with the problem of controlling anaerobic digestion processes. A two-step (i.e. acidogenesis-methanization) mass balance model is considered for a 1 m3 fixed bed digester treating industrial wine distillery wastewater. The control law aims at regulating the organic pollution level while avoiding washout of biomass. To this end, a simple output feedback controller is considered which regulates a variable strongly related to the Chemical Oxygen Demand (COD). Numerical simulations assuming noisy measurements first illustrate the robustness of this control procedure. Then, the regulating procedure is implemented on the considered anaerobic digestion process in order to validate and demonstrate its efficiency in real life experiments. PMID:14640204

  11. Anaerobic treatment of wastewater containing methanol in upflow anaerobic sludge bed (UASB) reactor

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The direct conversion of methanol into methane is the main process in anaerobic treatment of methanol containing wastewater.However,acetic acid can also be produced from methanol theoretically,which may probably result in an abrupt pH drop and deteriorate the anaerobic process.Therefore,it is interesting to know what would really happen in an anaerobic reactor treating methanol wastewater.In this study,an up-flow anaerobic sludge bed (UASB) reactor treating methanol wastewater was operated.The chemical oxygen demand (COD),acetic acid and pH of the effluent were monitored at different loadings and influent alkalinity.The results showed that the anaerobic reactor could be operated steadily at as low as 119 mg/L of influent alkalinity and high organic loading rate with no obvious pH drops.Volatile fatty acids accumulation was not observed even at strong shock loadings.The microorganisms in the sludge at the end of the test became homogeneous in morphology,which were mainly spherical or spheroidal in shape.

  12. Running-based Anaerobic Sprint Test as a Procedure to Evaluate Anaerobic Power.

    Science.gov (United States)

    Andrade, V L; Zagatto, A M; Kalva-Filho, C A; Mendes, O C; Gobatto, C A; Campos, E Z; Papoti, M

    2015-12-01

    The aim of this study was to evaluate the use of the running anaerobic sprint test (RAST) as a predictor of anaerobic capacity, compare it to the maximal accumulated oxygen deficit (MAOD) and to compare the RAST's parameters with the parameters of 30-s all-out tethered running on a treadmill. 39 (17.0±1.4 years) soccer players participated in this study. The participants underwent an incremental test, 10 submaximal efforts [50-95% of velocity correspondent to VO(2MAX) (vVO(2MAX))] and one supramaximal effort at 110% of vVO(2MAX) for the determination of MAOD. Furthermore, the athletes performed the RAST. In the second stage the 30-s all-out tethered running was performed on a treadmill (30-s all-out), and compared with RAST. No significant correlation was observed between MAOD and RAST parameters. However, significant correlations were found between the power of the fifth effort (P5) of RAST with peak and mean power of 30-s all-out (r=0.73 and 0.50; p<0.05, respectively). In conclusion, the parameters from RAST do not have an association with MAOD, suggesting that this method should not be used to evaluate anaerobic capacity. Although the correlations between RAST parameters with 30-s all-out do reinforce the RAST as an evaluation method of anaerobic metabolism, such as anaerobic power. PMID:26422055

  13. Sulfate-reducing bacteria in anaerobic bioreactors.

    OpenAIRE

    Oude Elferink, S.J.W.H.

    1998-01-01

    The treatment of industrial wastewaters containing high amounts of easily degradable organic compounds in anaerobic bioreactors is a well-established process. Similarly, wastewaters which in addition to organic compounds also contain sulfate can be treated in this way. For a long time, the occurrence of sulfate reduction was considered to be undesired. However, there are some recent developments in which sulfate reduction is optimized for the removal of sulfur compounds from waste streams. In...

  14. Anaerobic digestion of food and vegetable waste

    OpenAIRE

    Jiang, Ying

    2012-01-01

    Food and vegetable wastes contribute a large percentage of the organic fraction of municipal solid waste (OFMSW), and anaerobic digestion potentially offers an ideal method for their management. Their chemical composition can, however, lead to unstable operation and in extreme cases complete process failure has been reported with this type of substrate. Semi-continuous trials on vegetable waste were carried out in laboratory-scale digesters with daily feed additions at different organic loadi...

  15. Anaerobic co-digestion of organic wastes

    OpenAIRE

    L. Neves

    2009-01-01

    Tese de doutoramento em Engenharia Química e Biológica Anaerobic digestion is an already established process but the increasing need of bio‐waste recovery has determined the emergence of new substrates, revamping the research in this field. Contrary to some other European countries, in Portugal this technology is still scarcely in use. Nonetheless, the current legislation endorses this application as a waste management and as an energy recovery process. The rapid growth of the ...

  16. Evaluation of the anaerobe effort capacity

    OpenAIRE

    Anca M. Ionescu

    2008-01-01

    This article aims at presenting the main methods by which can be evaluated the effort anaerobe capacity, as well as their rolein conducting the physical training, depending on the performance level, sportsman’s preparation level, training stage, age andsex; depending on the above-mentioned criteria, are recommended certain tests, related mainly to the specificity (intensity,duration) of the practiced effort. Also, the concomitant appreciation of the aerobe capacity can direct us in evaluation...

  17. Anaerobic digestion in sustainable biomass chains

    OpenAIRE

    Pabon Pereira, C.P.

    2009-01-01

    This thesis evaluates the potential contribution of anaerobic digestion (AD) to the sustainability of biomass chains. Results provide insights in the technological potential to recover energy and valuable by-products from energy crops and residues, and evaluate biomass cascades involving AD technology for their feasibility and desirability. Embedding AD in biomass chains addresses current constraints towards increased use of biomass for energy production considering land competition and envir...

  18. Monitoring and control of anaerobic reactors

    DEFF Research Database (Denmark)

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær; Stamatelatou, K.; Lyberatos, G.

    2003-01-01

    The current status in monitoring and control of anaerobic reactors is reviewed. The influence of reactor design and waste composition on the possible monitoring and control schemes is examined. After defining the overall control structure, and possible control objectives, the possible process...... control approaches that have been used are comprehensively described. These include simple and adaptive controllers, as well as more recent developments such as fuzzy controllers, knowledge-based controllers and controllers based on neural networks....

  19. Monitoring and control of anaerobic reactors

    DEFF Research Database (Denmark)

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær; Stamatelatou, K.; Lyberatos, G.

    The current status in monitoring and control of anaerobic reactors is reviewed. The influence of reactor design and waste composition on the possible monitoring and control schemes is examined. After defining the overall control structure, and possible control objectives, the possible process...... control approaches that have been used are comprehensively described. These include simple and adaptive controllers, as well as more recent developments such as fuzzy controllers, knowledge-based controllers and controllers based on neural networks....

  20. Anaerobic microbial LCFA degradation in bioreactors

    OpenAIRE

    Sousa, D.Z.; Pereira, M.A.; Alves, J.I.; Smidt, Hauke; Stams, A.J.M.; Alves, M. M.

    2008-01-01

    This paper reviews recent results obtained on long-chain fatty acids (LCFA) anaerobic degradation. Two LCFA were used as model substrates: oleate, a mono-unsaturated LCFA, and palmitate, a saturated LCFA, both abundant in LCFA-rich wastewaters. 16S rRNA gene analysis of sludge samples submitted to continuous oleate- and palmitate-feeding followed by batch degradation of the accumulated LCFA demonstrated that bacterial communities were dominated by members of the Clostridiaceae and Sy...

  1. Anaerobic membrane bioreactors: Are membranes really necessary?

    OpenAIRE

    Davila, M.; Kassab, G.; Klapwijk, A.; Van, Lier, G

    2008-01-01

    Membranes themselves represent a significant cost for the full scale application of anaerobic membrane bioreactors (AnMBR). The possibility of operating an AnMBR with a self-forming dynamic membrane generated by the substances present in the reactor liquor would translate into an important saving. A self-forming dynamic membrane only requires a support material over which a cake layer is formed, which determines the rejection properties of the system. The present research studies the applicat...

  2. Physiologically anaerobic microorganisms of the deep subsurface

    International Nuclear Information System (INIS)

    Anaerobic bacteria were isolated from deep subsurface sediment samples taken at study sites in Idaho (INEL) and Washington (HR) by culturing on dilute and concentrated medium. Morphologically distinct colonies were purified, and their responses to 21 selected physiological tests were determined. Although the number of isolates was small (18 INEL, 27 HR) some general patterns could be determined. Most strains could utilize all the carbon sources, however the glycerol and melizitose utilization was positive for 50% or less of the HR isolates. Catalase activity (27.78% at INEL, 74.07% at HR) and tryptophan metabolism (11.12% at INEL, 40.74% at HR) were significantly different between the two study sites. MPN and viable counts indicate that sediments near the water table yield the greatest numbers of anaerobes. Deeper sediments also appear to be more selective with the greatest number of viable counts on low-nutrient mediums. Likewise, only strictly obligate anaerobes were found in the deepest sediment samples. Selective media indicated the presence of methanogens, acetogens, and sulfate reducers at only the HR site

  3. Alternating Current Influences Anaerobic Electroactive Biofilm Activity.

    Science.gov (United States)

    Wang, Xin; Zhou, Lean; Lu, Lu; Lobo, Fernanda Leite; Li, Nan; Wang, Heming; Park, Jaedo; Ren, Zhiyong Jason

    2016-09-01

    Alternating current (AC) is known to inactivate microbial growth in suspension, but how AC influences anaerobic biofilm activities has not been systematically investigated. Using a Geobacter dominated anaerobic biofilm growing on the electrodes of microbial electrochemical reactors, we found that high frequency AC ranging from 1 MHz to 1 kHz (amplitude of 5 V, 30 min) showed only temporary inhibition to the biofilm activity. However, lower frequency (100 Hz, 1.2 or 5 V) treatment led to 47 ± 19% permanent decrease in limiting current on the same biofilm, which is attributed to the action of electrohydrodynamic force that caused biofilm damage and loss of intercellular electron transfer network. Confocal microscopy images show such inactivation mainly occurred at the interface between the biofilm and the electrode. Reducing the frequency further to 1 Hz led to water electrolysis, which generated gas bubbles that flushed all attached cells out of the electrode. These findings provide new references on understanding and regulating biofilm growth, which has broader implications in biofouling control, anaerobic waste treatment, energy and product recovery, and general understanding of microbial ecology and physiology. PMID:27485403

  4. Anaerobic Treatment of Palm Oil Mill Effluent in Pilot-Scale Anaerobic EGSB Reactor.

    Science.gov (United States)

    Wang, Jin; Mahmood, Qaisar; Qiu, Jiang-Ping; Li, Yin-Sheng; Chang, Yoon-Seong; Li, Xu-Dong

    2015-01-01

    Large volumes of untreated palm oil mill effluent (POME) pose threat to aquatic environment due to the presence of very high organic content. The present investigation involved two pilot-scale anaerobic expanded granular sludge bed (EGSB) reactors, continuously operated for 1 year to treat POME. Setting HRT at 9.8 d, the anaerobic EGSB reactors reduced COD from 71179 mg/L to 12341 mg/L and recycled half of sludge by a dissolved air flotation (DAF). The average effluent COD was 3587 mg/L with the consistent COD removal efficiency of 94.89%. Adding cationic polymer (PAM) dose of 30 mg/L to DAF unit and recycling its half of sludge caused granulation of anaerobic sludge. Bacilli and small coccid bacteria were the dominant microbial species of the reactor. The reactor produced 27.65 m(3) of biogas per m(3) of POME which was utilized for electricity generation. PMID:26167485

  5. Anaerobic Treatment of Palm Oil Mill Effluent in Pilot-Scale Anaerobic EGSB Reactor

    OpenAIRE

    2015-01-01

    Large volumes of untreated palm oil mill effluent (POME) pose threat to aquatic environment due to the presence of very high organic content. The present investigation involved two pilot-scale anaerobic expanded granular sludge bed (EGSB) reactors, continuously operated for 1 year to treat POME. Setting HRT at 9.8 d, the anaerobic EGSB reactors reduced COD from 71179 mg/L to 12341 mg/L and recycled half of sludge by a dissolved air flotation (DAF). The average effluent COD was 3587 mg/L with ...

  6. A bio-electrochemical system for removing inhibitors of anaerobic digestion processes from anaerobic reactors

    DEFF Research Database (Denmark)

    2014-01-01

    reactor to recover ammonia from anaerobic digestion reactor, and thereby alleviate or counteract ammonia inhibition and enhance the conversion of ammonia-rich wastes to biogas. The invention may further reduce overall cost, giving synergistic advantages for both ammonia recycling and biogas plants......Inhibition of anaerobic digestion process by high level of ammonia (NH4 +/I\\IH3) is the most serious problem existing in biogas plants. No viable/applicable method to overcome this problem has been found up to now. This invention proposes an innovative submersible bio-electrochemical membrane...

  7. Two-phase anaerobic digestion of coffee wet wastewater: Effect of recycle on anaerobic process performance

    OpenAIRE

    Yans Guardia Puebla; Suyén Rodríguez Pérez; Yennys Cuscó Varona; Janet Jiménez Hernández; Víctor Sánchez Girón

    2014-01-01

    The present work shows the results of the two-phase anaerobic digestion assessment for the treatment of coffee wet wastewater. The effect of recycle on the anaerobic digestion process was studied. Twooverall organic loading rate (OLR) values of 4,2 and 5,7 kgCOD·m -3 ·d -1 , with same overall hydraulic retention time (HRT) of 21,5 h was evaluated.In a two-phase system wereapplied two recycle rate of 0,4 and 1,0, of the effluent of an UASB-UAF methanogenic hybrid reactor towards an UASB acidog...

  8. Control of calcium carbonate precipitation in anaerobic reactors.

    OpenAIRE

    Langerak, van, B.

    1998-01-01

    Anaerobic treatment of waste waters with a high calcium content may lead to excessive precipitation of calcium carbonate. So far, no proper methods were available to predict or reduce the extent of precipitation in an anaerobic treatment system. Moreover, it also was not clear to what extent precipitation in an anaerobic reactor can be tolerated because adequate knowledge on the structure and quality of methanogenic sludges with high calcium carbonate content was lacking. In this thesis, the ...

  9. Bacterial ecology of abattoir wastewater treated by an anaerobic digestor

    OpenAIRE

    Linda Jabari; Hana Gannoun; Eltaief Khelifi; Jean-Luc Cayol; Jean-Jacques Godon; Moktar Hamdi; Marie-Laure Fardeau

    2016-01-01

    Abstract Wastewater from an anaerobic treatment plant at a slaughterhouse was analysed to determine the bacterial biodiversity present. Molecular analysis of the anaerobic sludge obtained from the treatment plant showed significant diversity, as 27 different phyla were identified. Firmicutes, Proteobacteria, Bacteroidetes, Thermotogae, Euryarchaeota (methanogens), and msbl6 (candidate division) were the dominant phyla of the anaerobic treatment plant and represented 21.7%, 18.5%, 11.5%, 9.4%,...

  10. APPLICATION OF ANAEROBIC BIOTECHNOLOGY FOR PHARMACEUTICAL WASTEWATER TREATMENT

    OpenAIRE

    Shreeshivadasan Chelliapan and Paul J. Sallis

    2011-01-01

    The wastewater generated from pharmaceutical industry generally contain high organic load and the treatment is primarily carried out using two major types of biological methods; aerobic and anaerobic. However, due to high strength, it is infeasible to treat some pharmaceutical wastewater using aerobic biological processes. As an alternative, an anaerobic process is preferred to remove high strength organic matter. Anaerobic wastewater treatment is considered as the most cost effective solutio...

  11. Anaerobic on-site wastewater treatment at low temperatures

    OpenAIRE

    Luostarinen, Sari

    2005-01-01

    Anaerobic on-site wastewater treatment at low temperaturesAnaerobic treatment stabilises the treated waste(water), and enables production of renewable energy (methane, hydrogen), and preservation of valuable resources (nutrients). Decentralised, on-site application of anaerobic treatment for communities or individual households may thus provide combined waste(water) management, energy production, and nutrient recovery. Two-phased UASB-septic tanks were feasible for treatment of synthetic blac...

  12. The anaerobic corrosion of carbon steel in concrete

    International Nuclear Information System (INIS)

    This is the final report of a 2 year programme aimed at (1) determining the rate of anaerobic corrosion of steel in concrete, (2) investigating the nature of the corrosion products formed on carbon steel embedded in cementitious material under anaerobic conditions and (3) evaluating the effect of hydrogen over-pressures on the rate of anaerobic corrosion. All experiments have been carried out at temperatures in the range 20-300C, ie ambient conditions. 4 refs.; 19 figs.; 6 tabs

  13. Energy production by anaerobic treatment of cheese whey

    International Nuclear Information System (INIS)

    Anaerobic treatment and methane generation potential of cheese whey, diluted with mud, were determined in the digester of an existing wastewater treatment plant in Switzerland. Lactose, main sugar in cheese whey, can be a useful indicator to evaluate serum anaerobic treatment. Conventional parameters of anaerobic digestion (Volatile Matter, Dry Matter, Fatty Volatile Acids, total Alkali metric Title) were measured after the introduction of different whey/sludge ratio demonstrating that, despite an overcharge of whey digester, its stability is never compromised. (Author)

  14. Modelling nitrite dynamics and associated feedback processes in the Benguela oxygen minimum zone

    Science.gov (United States)

    Mashifane, T. B.; Vichi, M.; Waldron, H. N.; Machu, E.; Garçonc, V.

    2016-08-01

    Understanding nitrite dynamics in oxygen minimum zones (OMZs) is a challenge as it represents an intermediary nitrogen species with a short turnover time. Nitrite is also reduced to nitrogen in OMZs, preventing its accumulation. This creates difficulties in detecting nitrite with colorimetric methods as concentrations may occur below detection limits in some regions. Nitrite concentrations are key to understanding intermediate nitrogen processes and their implication for nitrogen loss in OMZs. A coupled physical-biogeochemical model is applied in the Benguela OMZ to study nitrite dynamics and its associated feedback processes. Simulated results show occurrence of primary and secondary nitrite maxima in the Benguela shelf waters. The primary nitrite maxima in the Benguela are attributed to nitrification and nitrate assimilation as they occur in association with the nitracline. Secondary nitrite maxima accumulate in the Angola-Benguela Front (ABF) OMZ and are attributed to denitrification. The secondary nitrite maxima are consumed by anaerobic ammonium oxidation (anammox) off Walvis Bay. Nitrite maxima are restricted to the shelf off Walvis Bay and advected offshore in the ABF region. Interchanges between the poleward South Atlantic Central Water (SACW) and the equatorward, well-aerated Eastern South Atlantic Central Water (ESACW) drive the seasonality of nitrogen processes in the Benguela. Subsequent nitrite reduction in the Benguela OMZ leads to nitrous oxide production, with high concentrations occurring in the ABF region as a result of nitrification and denitrification. Off Walvis Bay, nitrous oxide production is low since nitrite is consumed by anammox. Nitrous oxide production occurs in thermocline, intermediate and deeper water masses in the ABF region. High N fluxes in the Benguela are attributed to nitrification as compared to anammox and denitrification. Results from this study demonstrate the role of intermediate nitrogen species in nitrogen feedback

  15. pH variation and influence in an autotrophic nitrogen removing biofilm system using an efficient numerical solution strategy

    DEFF Research Database (Denmark)

    Vangsgaard, Anna Katrine; Mauricio Iglesias, Miguel; Valverde Perez, Borja; Gernaey, Krist; Sin, Gürkan

    2013-01-01

    nitritation-anammox process for a range of operating points. The simulation results showed that pH profiles were consistently increasing with increasing depth into the granule, since the proton producing aerobic ammonium oxidizers (AOB) were located close to the granule surface.Despite this pH profile, more...

  16. Anaerobic Metabolism and Bioremediation of Explosives-Contaminated Soil

    Science.gov (United States)

    Boopathy, Raj

    Nitroaromatic compounds pollute soil, water, and food via use of pesticides, plastics, pharmaceuticals, landfill dumping of industrial wastes, and the military use of explosives. Biotransformation of trinitrotoluene and other nitroaromatics by aerobic bacteria in the laboratory has been frequently reported, but the anaerobic bacterial metabolism of nitroaromatics has not been studied as extensively perhaps due to the difficulty in working with anaerobic cultures and the slow growth of anaerobes. Sulfate-reducing and methanogenic bacteria can metabolize nitroaromatic compounds under anaerobic conditions if appropriate electron donors and electron acceptors are present in the environment.

  17. Application of Anaerobic Digestion Model No. 1 for simulating anaerobic mesophilic sludge digestion

    Energy Technology Data Exchange (ETDEWEB)

    Mendes, Carlos, E-mail: carllosmendez@gmail.com; Esquerre, Karla, E-mail: karlaesquerre@ufba.br; Matos Queiroz, Luciano, E-mail: lmqueiroz@ufba.br

    2015-01-15

    Highlights: • The behavior of a anaerobic reactor was evaluated through modeling. • Parametric sensitivity analysis was used to select most sensitive of the ADM1. • The results indicate that the ADM1 was able to predict the experimental results. • Organic load rate above of 35 kg/m{sup 3} day affects the performance of the process. - Abstract: Improving anaerobic digestion of sewage sludge by monitoring common indicators such as volatile fatty acids (VFAs), gas composition and pH is a suitable solution for better sludge management. Modeling is an important tool to assess and to predict process performance. The present study focuses on the application of the Anaerobic Digestion Model No. 1 (ADM1) to simulate the dynamic behavior of a reactor fed with sewage sludge under mesophilic conditions. Parametric sensitivity analysis is used to select the most sensitive ADM1 parameters for estimation using a numerical procedure while other parameters are applied without any modification to the original values presented in the ADM1 report. The results indicate that the ADM1 model after parameter estimation was able to predict the experimental results of effluent acetate, propionate, composites and biogas flows and pH with reasonable accuracy. The simulation of the effect of organic shock loading clearly showed that an organic shock loading rate above of 35 kg/m{sup 3} day affects the performance of the reactor. The results demonstrate that simulations can be helpful to support decisions on predicting the anaerobic digestion process of sewage sludge.

  18. Application of Anaerobic Digestion Model No. 1 for simulating anaerobic mesophilic sludge digestion

    International Nuclear Information System (INIS)

    Highlights: • The behavior of a anaerobic reactor was evaluated through modeling. • Parametric sensitivity analysis was used to select most sensitive of the ADM1. • The results indicate that the ADM1 was able to predict the experimental results. • Organic load rate above of 35 kg/m3 day affects the performance of the process. - Abstract: Improving anaerobic digestion of sewage sludge by monitoring common indicators such as volatile fatty acids (VFAs), gas composition and pH is a suitable solution for better sludge management. Modeling is an important tool to assess and to predict process performance. The present study focuses on the application of the Anaerobic Digestion Model No. 1 (ADM1) to simulate the dynamic behavior of a reactor fed with sewage sludge under mesophilic conditions. Parametric sensitivity analysis is used to select the most sensitive ADM1 parameters for estimation using a numerical procedure while other parameters are applied without any modification to the original values presented in the ADM1 report. The results indicate that the ADM1 model after parameter estimation was able to predict the experimental results of effluent acetate, propionate, composites and biogas flows and pH with reasonable accuracy. The simulation of the effect of organic shock loading clearly showed that an organic shock loading rate above of 35 kg/m3 day affects the performance of the reactor. The results demonstrate that simulations can be helpful to support decisions on predicting the anaerobic digestion process of sewage sludge

  19. Oxygen tolerance capacity of upflow anaerobic solid-state (UASS) with anaerobic filter (AF) system.

    Science.gov (United States)

    Meng, Yao; Jost, Carsten; Mumme, Jan; Wang, Kaijun; Linke, Bernd

    2016-07-01

    In order to investigate the oxygen tolerance capacity of upflow anaerobic solid-state (UASS) with anaerobic filter (AF) system, the effect of microaeration on thermophilic anaerobic digestion of maize straw was investigated under batch conditions and in the UASS with AF system. Aeration intensities of 0-431mL O2/gvs were conducted as pretreatment under batch conditions. Aeration pretreatment obviously enhanced anaerobic digestion and an aeration intensity of 431mL O2/gvs increased the methane yield by 82.2%. Aeration intensities of 0-355mL O2/gvs were conducted in the process liquor circulation of the UASS with AF system. Dissolved oxygen (DO) of UASS and AF reactors kept around 1.39±0.27 and 0.99±0.38mg/L, respectively. pH was relatively stable around 7.11±0.04. Volatile fatty acids and soluble chemical oxygen demand concentration in UASS reactor were higher than those in AF reactor. Methane yield of the whole system was almost stable at 85±7mL/gvs as aeration intensity increased step by step. The UASS with AF system showed good oxygen tolerance capacity. PMID:27372134

  20. [Distribution and removal of anaerobic antibiotic resistant bacteria during mesophilic anaerobic digestion of sewage sludge].

    Science.gov (United States)

    Tong, Juan; Wang, Yuan-Yue; Wei Yuan, Song

    2014-10-01

    Sewage sludge is one of the major sources that releasing antibiotic resistant bacteria (ARB) and antibiotic resistant genes (ARG) into the environment since it contains large amount of ARB, but there is little information about the fate of the anaerobic ARB in the anaerobic digestion of sewage sludge. Therefore, the distribution, removal and seasonal changes of tetracycline and β-lactam antibiotics resistant bacteria in the mesophilic egg-shaped digesters of a municipal wastewater treatment plant were investigated for one year in this study. Results showed that there were higher amounts of ARB and higher resistance rate of β-lactam antibiotics than that of tetracycline antibiotics in the sewage sludge. All ARB could be significantly reduced during the mesophilic anaerobic digestion process by 1.48-1.64 log unit (P < 0.05). Notably, the ampicillin and cephalothin resistance rates were significantly increased after anaerobic digestion by 12.0% and 14.3%, respectively (P < 0.05). The distribution of ARB in the sewage sludge had seasonal change characteristics. Except for chlorotetracycline resistant bacteria, there were more ARB in the sewage sludge in cold season than in warm season (P < 0.05). PMID:25693388

  1. Two-phase anaerobic digestion of coffee wet wastewater: Effect of recycle on anaerobic process performance

    Directory of Open Access Journals (Sweden)

    Yans Guardia Puebla

    2014-01-01

    Full Text Available The present work shows the results of the two-phase anaerobic digestion assessment for the treatment of coffee wet wastewater. The effect of recycle on the anaerobic digestion process was studied. Twooverall organic loading rate (OLR values of 4,2 and 5,7 kgCOD·m -3 ·d -1 , with same overall hydraulic retention time (HRT of 21,5 h was evaluated.In a two-phase system wereapplied two recycle rate of 0,4 and 1,0, of the effluent of an UASB-UAF methanogenic hybrid reactor towards an UASB acidogenic reactor. In the anaerobic system with a recycle rate of 1,0 the total chemical oxygen demand (COD removal was 90%. The introduction of the recycle decreased the concentration of total volatile fatty acids (VFA, but it did not affect their composition, suggesting that the degradation pattern did not change. The presence of the acidogenic reactor in the two-phase system improved the stability of the anaerobic digestion process and increased the efficiency of methanogenic digester.

  2. Horse manure as feedstock for anaerobic digestion.

    Science.gov (United States)

    Hadin, Sa; Eriksson, Ola

    2016-10-01

    Horse keeping is of great economic, social and environmental benefit for society, but causes environmental impacts throughout the whole chain from feed production to manure treatment. According to national statistics, the number of horses in Sweden is continually increasing and is currently approximately 360,000. This in turn leads to increasing amounts of horse manure that have to be managed and treated. Current practices could cause local and global environmental impacts due to poor performance or lack of proper management. Horse manure with its content of nutrients and organic material can however contribute to fertilisation of arable land and recovery of renewable energy following anaerobic digestion. At present anaerobic digestion of horse manure is not a common treatment. In this paper the potential for producing biogas and biofertiliser from horse manure is analysed based on a thorough literature review in combination with mathematical modelling and simulations. Anaerobic digestion was chosen as it has a high degree of resource conservation, both in terms of energy (biogas) and nutrients (digestate). Important factors regarding manure characteristics and operating factors in the biogas plant are identified. Two crucial factors are the type and amount of bedding material used, which has strong implications for feedstock characteristics, and the type of digestion method applied (dry or wet process). Straw and waste paper are identified as the best materials in an energy point of view. While the specific methane yield decreases with a high amount of bedding, the bedding material still makes a positive contribution to the energy balance. Thermophilic digestion increases the methane generation rate and yield, compared with mesophilic digestion, but the total effect is negligible. PMID:27396682

  3. Anaerobic wastewater treatment of concentrated sewage using a two-stage upflow anaerobic sludge blanket- anaerobic filter system.

    Science.gov (United States)

    Halalsheh, Maha M; Abu Rumman, Zainab M; Field, Jim A

    2010-01-01

    A two-stage pilot-scale upflow anaerobic sludge blanket - anaerobic filter (UASB-AF) reactors system treating concentrated domestic sewage was operated at 23 degrees C and at hydraulic retention times (HRT) of 15 and 4 h, respectively. Excess sludge from the downstream AF stage was returned to the upstream UASB reactor. The aim was to obtain higher sludge retention time (SRT) in the UASB reactor for better methanization of suspended COD. The UASB-AF system removed 55% and 65% of the total COD (COD(tot)) and suspended COD (COD(ss)), respectively. The calculated SRT in the UASB reactor ranged from 20-35 days. The AF reactor removed the washed out sludge from the first stage reactor with average COD(ss) removal efficiency of 55%. The volatile fatty acids concentration in the effluent of the AF was 39 mg COD/L compared with 78 mg COD/L measured for the influent. The slightly higher COD(tot) removal efficiency obtained in this study compared with a single stage UASB reactor was achieved at 17% reduction in the total volume. PMID:20390881

  4. Improvement of anaerobic digestion of sludge

    Energy Technology Data Exchange (ETDEWEB)

    Dohanyos, Michael; Zabranska, Jana; Kutil, Josef; Jenicek, Pavel

    2003-07-01

    Anaerobic digestion improvement can be accomplished by different methods. Besides optimization of process conditions is frequently used pretreatment of input sludge and increase of process temperature. Thermophilic process brings a higher solids reduction and biogas production, the high resistance to foaming, no problems with odour, the higher effect of destroying pathogens and the improvement of the energy balance of the whole treatment plant. Disintegration of excess activated sludge in lysate centrifuge was proved in full-scale conditions causing increase of biogas production. The rapid thermal conditioning of digested sludge is acceptable method of particulate matter disintegration and solubilization. (author)

  5. The anaerobic digestion of sugar beet pulp

    OpenAIRE

    Suhartini, Sri

    2014-01-01

    World-wide there are substantial quantities of sugar beet pulp, which arises as a residue after the processing of whole beet to extract sugar for refining as a foodstuff or for use in fermentation, in particular for the production of ethanol for the biofuel market. In both cases the resulting pulp residue is still rich in pentose sugars and fibre, and the research considered anaerobic digestion (AD) as a potential technology for the conversion of this material into renewable energy in the for...

  6. Anaerobic Pre-treatment of Strong Sewage

    OpenAIRE

    Halalsheh, M.M.

    2002-01-01

    The main objective of this research was to assess the feasibility of applying low cost anaerobic technology for the treatment of relatively high strength sewage of Jordan using two-stage and one-stage UASB reactors operated at ambient temperatures. The wastewater produced in Jordan is characterised by a high concentration of COD tot with averages higher than 1200 mg/l and with a large fraction in the suspended form (65-70%). The average wastewater temperature fluctuates between 18 and 25 oC f...

  7. Monitoring and control of anaerobic reactors

    DEFF Research Database (Denmark)

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær;

    2003-01-01

    The current status in monitoring and control of anaerobic reactors is reviewed. The influence of reactor design and waste composition on the possible monitoring and control schemes is examined. After defining the overall control structure, and possible control objectives, the possible process...... measurements are reviewed in detail. In the sequel, possible manipulated variables, such as the hydraulic retention time, the organic loading rate, the sludge retention time, temperature, pH and alkalinity are evaluated with respect to the two main reactor types: high-rate and low-rate. Finally, the different...

  8. Oxygen, a regulating factor for nitrogen cycling in continental shelf sediments?

    Science.gov (United States)

    Neubacher, E.; Parker, R.; Trimmer, M.

    2009-04-01

    Oxygen is a fundamental parameter in regulating the cycling of carbon and nitrogen in continental shelf seas. Recent studies and models have shown that some regions of coastal seas are prone to a lack of oxygen and under such conditions, the dynamics of the nitrogen cycle could be altered. We measured rates of denitrification, anaerobic ammonium oxidation (anammox), oxygen uptake, nutrient exchange and pore water profiles of oxygen in sediments of the southern North Sea experimentally exposed to different oxygen saturations. The incubation of sediment at 33% (of air-saturation) for oxygen reduced the penetration and consumption of oxygen by the sediment by of approximately 50%, with a new steady state being reached after approximately 75 min. The rates of the various processes showed strong seasonality over the survey period (2007-2008), with denitrification ranging from 0.6 to 21.2 mol N m-2 h-1, anammox 0.2 to 4.4 mol N m-2 h-1 and oxygen uptake 46.5 to 631.8 mol O2 m-2 h-1. At the reduced saturation for oxygen (~ 33%), denitrification increased significantly (30%) while anammox remained constant. On average anammox accounted for 14-28% of the total production of di-nitrogen (N2) gas. Under ambient oxygen saturation, the rates of oxygen uptake and total production of N2 were positively correlated with each other (r = 0.73, p = 0.01, n = 230). The increase in denitrification was coupled to a change in NO3- flux. Under ambient oxygen there was a net release of 10.5 mol NO3- m-2 h-1 from the sediment to the water column, whereas under reduced oxygen, the sediments became a sink for NO3- (-1.2 mol NO3- m-2 h-1) from the overlaying water. These results suggest that facultative denitrifying bacteria were able to exploit the newly extended suboxic sediment layer, while the monophyletic group of anammox bacteria were not as flexible.

  9. Deforestation for oil palm alters the fundamental balance of the soil N cycle

    Science.gov (United States)

    Hamilton, Liz; Trimmer, Mark; Bradley, Chris; Pinay, Gilles

    2016-04-01

    Expansion of commercial agriculture in equatorial regions has significant implications for regional nitrogen (N) budgets, particularly nitrous oxide (N2O) and nitric oxide (NO) emissions, produced largely by microbial nitrification and denitrification. However, current estimates of soil N turnover are poorly constrained in Southeast Asia for nitrogen gas (N2) production and lesser known N transformations such as nitrate ammonification (DNRA) and anaerobic ammonium oxidation (anammox). We investigated changes in N availability and turnover following replacement of tropical forest with oil palm plantations along a chronosequence of oil palm maturity (3-months to 15-year-old stands) and secondary to primary forest succession in Sabah, Malaysian Borneo. Samples were taken from ten sites during March and April 2012. Using 15N tracing techniques, we measured rates of gross ammonium (NH4+) and nitrate (NO3‑) production (mineralisation and nitrification) and consumption (n= 8), potential denitrification, DNRA and anammox (n= 12) in soil cores and slurries respectively. Gross mineralisation rates (0.05 - 3.08 g N m‑2 d‑1) remained unchanged in oil palm relative to forests. However, a significant reduction in gross nitrification (0.04 - 2.31 g N m‑2 d‑1) and an increase in NH4+ immobilisation disrupt the pathway to N2 production substantially reducing (by > 90%) rates of denitrification and anammox in recently planted oil palm relative to primary forest. In forests, N2 produced via anammox was ˜30% of that from denitrification highlighting the potential for anammox to contribute significantly to N2 production. NH4+ production rates from DNRA were over two orders of magnitude less than N2 production rates indicating that denitrification is the primary dissimilatory nitrate consumption process in these soils. Potential N2O emissions were greater than potential N2 production, remaining unchanged across the chronosequence and indicating an increased N2O:N2 emission

  10. Nitrate reduction, nitrous oxide formation, and anaerobic ammonia oxidation to nitrite in the gut of soil-feeding termites (Cubitermes and Ophiotermes spp.)

    KAUST Repository

    Ngugi, David

    2011-11-28

    Soil-feeding termites play important roles in the dynamics of carbon and nitrogen in tropical soils. Through the mineralization of nitrogenous humus components, their intestinal tracts accumulate enormous amounts of ammonia, and nitrate and nitrite concentrations are several orders of magnitude above those in the ingested soil. Here, we studied the metabolism of nitrate in the different gut compartments of two Cubitermes and one Ophiotermes species using 15N isotope tracer analysis. Living termites emitted N 2 at rates ranging from 3.8 to 6.8nmolh -1 (g fresh wt.) -1. However, in homogenates of individual gut sections, denitrification was restricted to the posterior hindgut, whereas nitrate ammonification occurred in all gut compartments and was the prevailing process in the anterior gut. Potential rates of nitrate ammonification for the entire intestinal tract were tenfold higher than those of denitrification, implying that ammonification is the major sink for ingested nitrate in the intestinal tract of soil-feeding termites. Because nitrate is efficiently reduced already in the anterior gut, reductive processes in the posterior gut compartments must be fuelled by an endogenous source of oxidized nitrogen species. Quite unexpectedly, we observed an anaerobic oxidation of 15N-labelled ammonia to nitrite, especially in the P4 section, which is presumably driven by ferric iron; nitrification and anammox activities were not detected. Two of the termite species also emitted substantial amounts of N 2O, ranging from 0.4 to 3.9nmolh -1 (g fresh wt.) -1, providing direct evidence that soil-feeding termites are a hitherto unrecognized source of this greenhouse gas in tropical soils. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  11. Enhanced biogas yield from energy crops with rumen anaerobic fungi

    Czech Academy of Sciences Publication Activity Database

    Procházka, J.; Mrázek, Jakub; Štrosová, Lenka; Fliegerová, Kateřina; Zábranská, J.; Dohányos, M.

    2012-01-01

    Roč. 12, č. 3 (2012), s. 343-351. ISSN 1618-0240 R&D Projects: GA ČR GPP503/10/P394; GA MZe QI92A286 Institutional support: RVO:67985904 Keywords : Anaerobic digestion * Anaerobic fungi * Biogas yield Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.633, year: 2012

  12. Control of calcium carbonate precipitation in anaerobic reactors.

    NARCIS (Netherlands)

    Langerak, van E.P.A.

    1998-01-01

    Anaerobic treatment of waste waters with a high calcium content may lead to excessive precipitation of calcium carbonate. So far, no proper methods were available to predict or reduce the extent of precipitation in an anaerobic treatment system. Moreover, it also was not clear to what extent precipi

  13. Solids removal in upflow anaerobic reactors, a review

    NARCIS (Netherlands)

    Mahmoud, N.; Zeeman, G.; Gijzen, H.J.; Lettinga, G.

    2003-01-01

    This desk study deals with the mechanisms and parameters affecting particles separation from wastewater in mainly upflow anaerobic reactors. Despite the fact that the functioning of upflow anaerobic sludge blanket (UASB) systems depends on both physical parameters and biological processes, the physi

  14. Differential production of slime under aerobic and anaerobic conditions.

    OpenAIRE

    Barker, L P; Simpson, W A; Christensen, G D

    1990-01-01

    A series of 37 clinical isolates of coagulase-negative staphylococci previously identified as negative for slime production by the tube test were reexamined by the tissue culture plate test under aerobic and anaerobic conditions. None of the strains produced slime under anaerobic conditions; however, five strains (13%) produced slime under aerobic conditions.

  15. TEST RESULTS FOR FUEL CELL OPERATION ON ANAEROBIC DIGESTER GAS

    Science.gov (United States)

    EPA, in conjunction with ONSI Corp., embarked on a project to define, design, test, and assess a fuel cell energy recovery system for application at anaerobic digester waste water (sewage) treatment plants. Anaerobic digester gas (ADG) is produced at these plants during the proce...

  16. Evidence of hydrolytic route for anaerobic cyanide degradation.

    OpenAIRE

    Fallon, R. D.

    1992-01-01

    Products observed during anaerobic cyanide transformation are consistent with a hydrolytic pathway (HCN + H2O HCONH2 + H2O HCOOH + NH3). Formate, the most frequently observed product, was generally converted to bicarbonate. Formamide was rapidly hydrolyzed to formate upon exposure to the anaerobic consortium but was not detected as an intermediate of cyanide transformation.

  17. Anaerobic digestion: biodegradability and biogas production of model wastes

    OpenAIRE

    Lausund, Erlend

    2014-01-01

    Anaerobic digestion is a desirable treatment practice in terms of minimizing volume, treating of pollutants and biogas production. In this thesis model wastes have been investigated with respect to biogas and methane production in order to find out what wastes are suitable for anaerobic digestion, and discussing ways to further the research to optimize the production of renewable energy.

  18. Methanol conversion in high-rate anaerobic reactors

    NARCIS (Netherlands)

    Weijma, J.; Stams, A.J.M.

    2001-01-01

    An overview on methanol conversion in high-rate anaerobic reactors is presented, with the focus on technological as well as microbiological aspects. The simple C1-compound methanol can be degraded anaerobically in a complex way, in which methanogens, sulfate reducing bacteria and homoacetogens inter

  19. The anaerobic digestion of solid organic waste.

    Science.gov (United States)

    Khalid, Azeem; Arshad, Muhammad; Anjum, Muzammil; Mahmood, Tariq; Dawson, Lorna

    2011-08-01

    The accumulation of solid organic waste is thought to be reaching critical levels in almost all regions of the world. These organic wastes require to be managed in a sustainable way to avoid depletion of natural resources, minimize risk to human health, reduce environmental burdens and maintain an overall balance in the ecosystem. A number of methods are currently applied to the treatment and management of solid organic waste. This review focuses on the process of anaerobic digestion which is considered to be one of the most viable options for recycling the organic fraction of solid waste. This manuscript provides a broad overview of the digestibility and energy production (biogas) yield of a range of substrates and the digester configurations that achieve these yields. The involvement of a diverse array of microorganisms and effects of co-substrates and environmental factors on the efficiency of the process has been comprehensively addressed. The recent literature indicates that anaerobic digestion could be an appealing option for converting raw solid organic wastes into useful products such as biogas and other energy-rich compounds, which may play a critical role in meeting the world's ever-increasing energy requirements in the future. PMID:21530224

  20. Anaerobic degradation kinetics of a cholesteryl ester.

    Science.gov (United States)

    Gutiérrez, S; Viñas, M

    2003-01-01

    The most important components of wool scouring effluent grease are esters of sterols. Cholesteryl palmitate (CP) is the main ester in this grease. In this paper, the influence of the ester concentration in the anaerobic digestion and the relative rate of the different degradation steps, are studied. The experiment was carried out to measure methane production in the anaerobic degradation of acetate, palmitic acid (PA) and CP. A first-order kinetic model was assumed for hydrolysis and Monod models were assumed for both the methanogenic and acetogenic steps. Maximum hydrolysis rate was found to be around 20 times faster than the maximum methanogenic reaction rate during the experience. The lanolin emulsion drop size effect was also evaluated employing fine and coarse stock lanolin emulsions and no adapted sludge. Concentrations of 13.7 to 4.6 gCOD x l(-1) were employed. In a previous study, the effect of palmitic acid emulsion size was found important when similar sludge was tested. When esters are degraded, a significant effect of drop size on the degradation rate was not found. The difference between CP and PA emulsions behavior could be due to the fact that cholesterol produced during the ester degradation has a protective effect on the sludge. PMID:14640211

  1. Anaerobic and aerobic transformation of TNT

    Energy Technology Data Exchange (ETDEWEB)

    Kulpa, C.F. [Univ. of Notre Dame, IN (United States). Dept. of Biological Sciences; Boopathy, R.; Manning, J. [Argonne National Lab., IL (United States). Environmental Research Div.

    1996-12-31

    Most studies on the microbial metabolism of nitroaromatic compounds have used pure cultures of aerobic microorganisms. In many cases, attempts to degrade nitroaromatics under aerobic conditions by pure cultures result in no mineralization and only superficial modifications of the structure. However, mixed culture systems properly operated result in the transformation of 2,4,6-trinitrotoluene (TNT) and in some cases mineralization of TNT occurs. In this paper, the mixed culture system is described with emphasis on intermediates and the characteristics of the aerobic microbial process including the necessity for a co-substrate. The possibility of removing TNT under aerobic/anoxic conditions is described in detail. Another option for the biodegradation of TNT and nitroaromatics is under anaerobic, sulfate reducing conditions. In this instance, the nitroaromatic compounds undergo a series of reductions with the formation of amino compounds. TNT under sulfate reducing conditions is reduced to triaminotoluene presumably by the enzyme nitrite reductase, which is commonly found in many Desulfovibrio spp. The removal of nitro groups from TNT is achieved by a series of reductive reactions with the formation of ammonia and toluene by Desulfovibrio sp. (B strain). These metabolic processes could be applied to other nitroaromatic compounds like nitrobenzene, nitrobenzoic acids, nitrophenols, and aniline. The data supporting the anaerobic transformation of TNT under different growth condition are reviewed in this report.

  2. Comparative economic analysis: Anaerobic digester case study

    International Nuclear Information System (INIS)

    An economic guide is developed to assess the value of anaerobic digesters used on dairy farms. Two varieties of anaerobic digesters, a conventional mixed-tank mesophilic and an innovative earthen psychrophilic, are comparatively evaluated using a cost-effectiveness index. The two case study examples are also evaluated using three other investment merit statistics: simple payback period, net present value, and internal rate of return. Life-cycle savings are estimated for both varieties, with sensitivities considered for investment risk. The conclusion is that an earthen psychrophilic digester can have a significant economic advantage over a mixed-tank mesophilic digester because of lower capital cost and reduced operation and maintenance expenses. Because of this economic advantage, additional projects are being conducted in North Carolina to increase the rate of biogas utilization. The initial step includes using biogas for milk cooling at the dairy farm where the existing psychrophilic digester is located. Further, a new project is being initiated for electricity production with thermal reclaim at a swine operation

  3. Mathematical modelling of anaerobic digestion processes: applications and future needs

    DEFF Research Database (Denmark)

    Batstone, Damien J.; Puyol, Daniel; Flores Alsina, Xavier;

    2015-01-01

    of the role of the central carbon catabolic metabolism in anaerobic digestion, with an increased importance of phosphorous, sulfur, and metals as electron source and sink, and consideration of hydrogen and methane as potential electron sources. The paradigm of anaerobic digestion is challenged by anoxygenic...... phototrophism, where energy is relatively cheap, but electron transfer is expensive. These new processes are commonly not compatible with the existing structure of anaerobic digestion models. These core issues extend to application of anaerobic digestion in domestic plant-wide modelling, with the need......Anaerobic process modelling is a mature and well-established field, largely guided by a mechanistic model structure that is defined by our understanding of underlying processes. This led to publication of the IWA ADM1, and strong supporting, analytical, and extension research in the 15 years since...

  4. Inhibition of the anaerobic digestion process by linear alkylbenzene sulfonates

    DEFF Research Database (Denmark)

    Gavala, Hariklia N.; Ahring, Birgitte Kiær

    2002-01-01

    it is important to investigate the effect of these xenobiotic compounds on an anaerobic environment. The inhibitory effect of Linear Alkylbenzene Sulfonates (LAS) on the acetogenic and methanogenic step of the anaerobic digestion process was studied. LAS inhibit both acetogenesis from propionate...... of the anaerobic digestion process should be seriously taken into consideration when wastewater from a surfactant producing industry is to be treated biologically or enter a municipal wastewater treatment plant that employs anaerobic technology. The upper allowable biomass specific LAS concentration should be 14......Linear Alkylbenzene Sulfonates (LAS) are the most widely used synthetic anionic surfactants. They are anthropogenic, toxic compounds and are found in the primary sludge generated in municipal wastewater treatment plants. Primary sludge is usually stabilized anaerobically and therefore...

  5. [Sensitivity of anaerobic bacteria to therapeutic agents (Zurich 1984)].

    Science.gov (United States)

    Wüst, J; Hardegger, U

    1985-12-28

    There are several reports in the literature on resistance of anaerobic bacteria against antimicrobial agents. Therefore, 231 anaerobic strains of various bacterial genera, isolated from clinical specimens during fall 1984, were tested for susceptibility to antimicrobial agents active against anaerobic bacteria. Whereas 23% of the Bacteroides species not belonging to the B. fragilis group were resistant to penicillin, the anaerobic bacteria were still susceptible to chloramphenicol, clindamycin and the nitroimidazoles. The resistance rate against the various new beta-lactam antibiotics was comparable to results of other studies. Due to the increasing resistance it is recommended that the susceptibility of clinically important anaerobes be tested by appropriate techniques. The agar diffusion test must not be used due to unreliable results. Instead, the minimal inhibitory concentration should be determined or the "broth-disk" test performed. PMID:4089587

  6. APPLICATION OF ANAEROBIC BIOTECHNOLOGY FOR PHARMACEUTICAL WASTEWATER TREATMENT

    Directory of Open Access Journals (Sweden)

    Shreeshivadasan Chelliapan and Paul J. Sallis

    2011-01-01

    Full Text Available The wastewater generated from pharmaceutical industry generally contain high organic load and the treatment is primarily carried out using two major types of biological methods; aerobic and anaerobic. However, due to high strength, it is infeasible to treat some pharmaceutical wastewater using aerobic biological processes. As an alternative, an anaerobic process is preferred to remove high strength organic matter. Anaerobic wastewater treatment is considered as the most cost effective solution for organically polluted industrial waste streams. In particular the development of high rate systems, in which hydraulic retention times (HRT are uncoupled from solids retention times (SRT, has led to a worldwide acceptance of anaerobic wastewater treatment. In this paper, literature on anaerobic digestion, anaerobic reactor technology and existing anaerobic treatment of pharmaceutical wastewater are presented. In addition, fate of pharmaceuticals in the environment was also discussed in brief. A case study of a laboratory investigation into the treatment of pharmaceutical wastewater containing the antibiotic Tylosin in an anaerobic reactor was also given. Specifically, it was determined whether the anaerobic reactor could be used as a pre-treatment system at an existing pharmaceutical production plant. The performance of the reactor treating real pharmaceutical wastewater at various organic loading rate (OLR was investigated and showed efficient substrate removal at low OLRs (0.43 – 1.86 kg COD.m-3.d-1 by promoting efficient chemical oxygen demand (COD reduction (70 – 75%. Under these conditions, an average of 95% Tylosin reduction was achieved in the UASR. However, increasing the OLRs to 3.73 kg COD.m-3.d-1 by reducing the hydraulic retention time (HRT (4 – 2 d reduced the COD removal efficiency (45%. Changes in the organic loading affected the treatment performance of the anaerobic reactor, and at high OLRs, it was not able to withstand the short

  7. Validity of the Pediatric Running-Based Anaerobic Sprint Test to Determine Anaerobic Performance in Healthy Children

    NARCIS (Netherlands)

    Bongers, Bart C.; Werkman, Maarten S.; Blokland, Donna; Eijsermans, Maria J. C.; van der Torre, Patrick; Bartels, Bart; Verschuren, Olaf; Takken, Tim

    2015-01-01

    Purpose: To determine criterion validity of the pediatric running-based anaerobic sprint test (RAST) as a nonsophisticated field test for evaluating anaerobic performance in healthy children and adolescents. Methods: Data from 65. healthy children (28 boys and 37 girls between 6 and 18 years of age,

  8. Arsenic volatilization in model anaerobic biogas digesters

    International Nuclear Information System (INIS)

    Highlights: • Arsenic is volatilized form all model anaerobic digesters, including the non-treated ones. • Volatile As species can be identified and quantified in all digesters. • Non-arsenic treated digesters volatilization rates are higher than Roxarsone treated ones. - Abstract: Arsenic is a class 1 non-threshold carcinogen which is highly ubiquitous. Arsenic undergoes many different transformations (biotic or abiotic) between and within environmental compartments, leading to a number of different chemical species possessing different properties and toxicities. One specific transformation is As biotic volatilization which is coupled with As biomethylation and has been scarcely studied due to inherent sampling issues. Arsenic methylation/volatilization is also linked with methanogenesis and occurs in anaerobic environments. In China, rice straw and animal manure are very often used to produce biogas and both can contain high amounts of As, especially if the rice is grown in areas with heavy mining or smelting industries and if Roxarsone is fed to the animals. Roxarsone is an As-containing drug which is widely used in China to control coccidian intestinal parasites, to improve feed efficiency and to promote rapid growth. Previous work has shown that this compound degrades to inorganic As under anaerobic conditions. In this study the focus is on biotic transformations of As in small microcosms designed as biogas digester models (BDMs) using recently validated As traps, thus, enabling direct quantification and identification of volatile As species. It is shown that although there was a loss of soluble As in the BDMs, their conditions favored biomethylation. All reactors produced volatile As, especially the monomethylarsonic acid spiked ones with 413 ± 148 ng As (mean ± SD, n = 3) which suggest that the first methylation step, from inorganic As, is a limiting factor. The most abundant species was trimethylarsine, but the toxic arsine was present in the

  9. Controls of Sediment Nitrogen Dynamics in Tropical Coastal Lagoons.

    Directory of Open Access Journals (Sweden)

    Alex Enrich-Prast

    Full Text Available Sediment denitrification rates seem to be lower in tropical environments than in temperate environments. Using the isotope pairing technique, we measured actual denitrification rates in the sediment of tropical coastal lagoons. To explain the low denitrification rates observed at all study sites (<5 μmol N2 m-2 h-1, we also evaluated potential oxygen (O2 consumption, potential nitrification, potential denitrification, potential anammox, and estimated dissimilatory nitrate (NO3- reduction to ammonium (NH4+; DNRA in the sediment. 15NO3- and 15NH4+ conversion was measured in oxic and anoxic slurries from the sediment surface. Sediment potential O2 consumption was used as a proxy for overall mineralization activity. Actual denitrification rates and different potential nitrogen (N oxidation and reduction processes were significantly correlated with potential O2 consumption. The contribution of potential nitrification to total O2 consumption decreased from contributing 9% at sites with the lowest sediment mineralization rates to less than 0.1% at sites with the highest rates. NO3- reduction switched completely from potential denitrification to estimated DNRA. Ammonium oxidation and nitrite (NO2- reduction by potential anammox contributed up to 3% in sediments with the lowest sediment mineralization rates. The majority of these patterns could be explained by variations in the microbial environments from stable and largely oxic conditions at low sediment mineralization sites to more variable conditions and the prevalences of anaerobic microorganisms at high sediment mineralization sites. Furthermore, the presence of algal and microbial mats on the sediment had a significant effect on all studied processes. We propose a theoretical model based on low and high sediment mineralization rates to explain the growth, activity, and distribution of microorganisms carrying out denitrification and DNRA in sediments that can explain the dominance or coexistence of

  10. Comparison of Aerobic and Anaerobic Biodegradation of Sugarcane Vinasse.

    Science.gov (United States)

    Mota, V T; Araújo, T A; Amaral, M C S

    2015-07-01

    Vinasse is the main liquid waste from ethanol production, and it has a considerable pollution potential. Biological treatment is a promising alternative to reduce its organic load. The aim of this study was to analyze the biodegradation of sugarcane juice vinasse in aerobic and anaerobic conditions. The content of carbohydrates, proteins and volatile fatty acids was evaluated. Vinasse samples showed a high biodegradability (>96.5 %) and low percentage of inert chemical oxygen demand (COD) (<3.2 %) in both aerobic and anaerobic conditions. The rates of substrate utilization were slightly higher in aerobic reactors, but COD stabilization occurred simultaneously in the anaerobic reactors, confirming its suitability for anaerobic digestion. Inert COD in anaerobic conditions was lower than in aerobic conditions. On the other hand, COD from metabolic products in the anaerobic reactors was higher than in the aerobic ones, indicating an increased release of soluble microbial products (SMPs) by anaerobic microorganisms. The results indicated that carbohydrates were satisfactorily degraded and protein-like substances were the major components remaining after biological degradation of vinasse. PMID:25957273

  11. Trace metal speciation and bioavailability in anaerobic digestion: A review.

    Science.gov (United States)

    Thanh, Pham Minh; Ketheesan, Balachandran; Yan, Zhou; Stuckey, David

    2016-01-01

    Trace metals are essential for the growth of anaerobic microorganisms, however, in practice they are often added to anaerobic digesters in excessive amounts, which can lead to inhibition. The concept of bioavailability of metals in anaerobic digestion has been poorly understood in the past, and a lack of deep understanding of the relationship between trace metal speciation and bioavailability can result in ineffective metal dosing strategies for anaerobic digesters. Sequential extraction schemes are useful for fractionating trace metals into their different forms, and metal sulfides can serve as a store and source for trace metals during anaerobic digestion, while natural/synthetic chelating agents (soluble microbial products-SMPs, extracellular polysaccharides-EPS, and EDTA/NTA) are capable of controlling trace metal bioavailability. Nevertheless, more work is needed to: investigate the speciation and bioavailability of Ca, Mg, Mn, W, and Se; compare the bioavailability of different forms of trace metals e.g. carbonates, sulfides, phosphates to different anaerobic trophic groups; determine what factors influence metal sulfide dissolution; investigate whether chelating agents can increase trace metal bioavailability; develop and adapt specialized analytical techniques, and; determine how trace metal dynamics change in an anaerobic membrane bioreactor (AnMBR). PMID:26707985

  12. Anaerobic Treatment of Palm Oil Mill Effluent in Pilot-Scale Anaerobic EGSB Reactor

    Directory of Open Access Journals (Sweden)

    Jin Wang

    2015-01-01

    Full Text Available Large volumes of untreated palm oil mill effluent (POME pose threat to aquatic environment due to the presence of very high organic content. The present investigation involved two pilot-scale anaerobic expanded granular sludge bed (EGSB reactors, continuously operated for 1 year to treat POME. Setting HRT at 9.8 d, the anaerobic EGSB reactors reduced COD from 71179 mg/L to 12341 mg/L and recycled half of sludge by a dissolved air flotation (DAF. The average effluent COD was 3587 mg/L with the consistent COD removal efficiency of 94.89%. Adding cationic polymer (PAM dose of 30 mg/L to DAF unit and recycling its half of sludge caused granulation of anaerobic sludge. Bacilli and small coccid bacteria were the dominant microbial species of the reactor. The reactor produced 27.65 m3 of biogas per m3 of POME which was utilized for electricity generation.

  13. [Antimicrobial susceptibility testing of anaerobic bacteria].

    Science.gov (United States)

    García-Sánchez, José E; García-Sánchez, Enrique; García-García, María Inmaculada

    2014-02-01

    The anaerobic bacteria resistance to antibiotics is increasing, and even has appeared against the most active of those, like metronidazol and carbapenems. This fact forces to make and periodical sensibility tests -at least in the most aggressive and virulent species, in cases that they are isolated from life locations and in the absence of therapeutic response- to check the local sensibility and to establish suitable empiric therapies, all based on multicentric studies carried out in order to this or well to check the activity of new antibiotics. For the laboratory routine, the easiest sensibility method is the E-test/MIC evaluator. Another alternative is microdilution, that's only normalized for Bacteroides. There are preliminary facts that allow the use of disc diffusion method in some species of Bacteroides and Clostridium. For the temporal and multicentric studies, the procedure is dilution in agar plate, the reference method. PMID:24630580

  14. PCB dechlorination in anaerobic soil slurry reactors

    International Nuclear Information System (INIS)

    Many industrial locations, including the US Department of Energy's, have identified needs for treatment of polychlorinated biphenyl (PCB) wastes and remediation of PCB-contaminated sites. Biodegradation of PCBs is a potentially effective technology for the treatment of PCB-contaminated soils and sludges, including mixed wastes; however, a practical remediation technology has not yet been demonstrated. In laboratory experiments, soil slurry bioreactors inoculated with microorganisms extracted from PCB-contaminated sediments from the Hudson River have been used to obtain anaerobic dechlorination of PCBS. The onset of dechlorination activity can be accelerated by addition of nutritional amendments and inducers. After 15 weeks of incubation with PCB-contaminated soil and nutrient solution, dechlorination has been observed under several working conditions. The best results show that the average chlorine content steadily dropped from 4.3 to 3.5 chlorines per biphenyl over a 15-week period

  15. Determining anaerobic degradation kinetics from batch tests.

    Science.gov (United States)

    Moreda, Iván López

    2016-01-01

    Data obtained from a biomethane potential (BMP) test were used in order to obtain the parameters of a kinetic model of solid wastes anaerobic degradation. The proposed model considers a hydrolysis step with a first order kinetic, a Monod kinetic for the soluble organic substrate degradation and a first order decay of microorganisms. The instantaneous release of methane was assumed. The parameters of the model are determined following a direct search optimization procedure. A 'multiple-shooting' technique was used as a first step of the optimization process. The confidence interval of the parameters was determined by using Monte Carlo simulations. Also, the distribution functions of the parameters were determined. Only the hydrolysis first order constant shows a normal distribution. PMID:27191569

  16. Photochemistry of hypocrellin derivatives under anaerobic conditions

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    To improve the red absorption and solubility of hypocrellin, we have synthesized a series of hypocrellin B derivatives. The photochemistry of these new compounds in anaerobic media has been investigated by using electronic paramagnetic resonance (EPR) and spectrophotometric methods. The semiquinone anion radicals can be produced by self-electron transfer on irradiation, with the formation efficiency and EPR hyperfine structures of the semiquinone anion radicals dependent on the structures of the derivatives. When an electron donor is present, the electron transfer from electron donor to hypocrellin B derivatives enhanced the production of the corresponding semiquinone anion radical; in addition, the semiquinone anion radical and hydroquinone can be detected spectrophotometrically. Structural modifications exert little effect on the absorption position of semiquinone anion radical and hydroquinone, but influence their formation efficiency significantly.

  17. Kinetics of biogas production in Anaerobic Filters.

    Science.gov (United States)

    Krümpel, Johannes; Schäufele, Friedrich; Schneider, Johannes; Jungbluth, Thomas; Zielonka, Simon; Lemmer, Andreas

    2016-01-01

    This study investigates methane production kinetics from individual volatile fatty acids (VFA) in an Upflow Anaerobic Filter (AF). 1gCOD in the form of acetic (HAc), propionic (HPr) or butyric acid (HBu) was injected into the AF while operating at an organic loading rate (OLRCOD) of 3.5gL(-1)d(-1). A new method is introduced to separate gas production of the baseload from the product formation of VFA degradation after the injection. The lag phase, fractional rate of gas production and half-life has been determined for the methane production of the three VFAs. The half-lives were in the order HAcenergy market with balancing power. PMID:26492176

  18. CFD simulation of mixing in anaerobic digesters.

    Science.gov (United States)

    Terashima, Mitsuharu; Goel, Rajeev; Komatsu, Kazuya; Yasui, Hidenari; Takahashi, Hiroshi; Li, Y Y; Noike, Tatsuya

    2009-04-01

    A three-dimensional CFD model incorporating the rheological properties of sludge was developed and applied to quantify mixing in a full-scale anaerobic digester. The results of the model were found to be in good agreement with experimental tracer response curve. In order to predict the dynamics of mixing, a new parameter, UI (uniformity index) was defined. The visual patterns of tracer mixing in simulation were well reflected in the dynamic variation in the value of UI. The developed model and methods were applied to determine the required time for complete mixing in a full-scale digester at different solid concentrations. This information on mixing time is considered to be useful in optimizing the feeding cycles for better digester performance. PMID:19081247

  19. Monitoring and control of anaerobic reactors

    DEFF Research Database (Denmark)

    Pind, Peter Frode; Angelidaki, Irini; Ahring, Birgitte Kiær;

    2003-01-01

    The current status in monitoring and control of anaerobic reactors is reviewed. The influence of reactor design and waste composition on the possible monitoring and control schemes is examined. After defining the overall control structure, and possible control objectives, the possible process...... measurements are reviewed in detail. In the sequel, possible manipulated variables, such as the hydraulic retention time, the organic loading rate, the sludge retention time, temperature, pH and alkalinity are evaluated with respect to the two main reactor types: high-rate and low-rate. Finally, the different...... control approaches that have been used are comprehensively described. These include simple and adaptive controllers, as well as more recent developments such as fuzzy controllers, knowledge-based controllers and controllers based on neural networks....

  20. Stabilization of degradable wastes by anaerobic process

    International Nuclear Information System (INIS)

    Within the framework of a modern waste management concept, separate collection and recycling of garden wastes and degradable wastes from households and trade are indispensable and correspond to a principle enshrined in law. The ''bion-stab'' technique is a closed-cycle process for anaerobic stabilization of degradable wastes which causes few emissions and is thus extremely environmentally friendly. Latent energy contained in degradable waste is liberated by this process. This energy is environmentally friendly, as the cycle process involves the release of bonded CO2 only for a short period of time. Thus it contributes, along with the high economic efficiency of the plant, to a positive overall result both in terms of energy and with regard to environmental problems. (orig.)

  1. Characterization of Spartina alterniflora as feedstock for anaerobic digestion

    International Nuclear Information System (INIS)

    Smooth cordgrass (Spartina alterniflora), a saltmarsh plant with high production, was characterized for its potential for use as feedstock for anaerobic digestion processes. The anaerobic digestibility and biogas yield of S. alterniflora were evaluated by anaerobic batch digestion experiments performed at 35 ± 1 C at initial volatile solids (VS) of 6%. The nutrient content analysis indicated that S. alterniflora contained the required nutrition for anaerobic microorganisms, but its high C/N of 58.8, high K and Na contents of 8.1, 22.7 g kg-1, respectively, may be disadvantageous to its anaerobic digestion. The cumulative biogas yield was determined to be 358 L kg-1 VS and the biodegradation efficiency was 45% after 60 days of digestion. The methane content of biogas increased from 53% on day 3 to around 62% after 13 days of digestion. The changes of volatile fatty acids (VFAs) indicated that the acidification of S. alterniflora was propionate-type fermentation with proportion of acetate and propionate ranging from 54.8% to 98.4%, and the hydrolysis of lignocellulose was the rate-limiting step for its anaerobic digestion. The analysis of cations suggested that K+ and Mg2+, with the maximum concentration of 1.35 and 0.43 g L-1 in fermentation liquor, respectively, could be inhibitory to the anaerobic digestion of S. alterniflora. It is concluded that S. alterniflora can be transformed into clean energy by anaerobic digestion and the high contents of K, Na, Ca and Mg may be the inhibitory factors when S. alterniflora is digested by continuous or semi-continuous anaerobic process. (author)

  2. Clostridium difficile: the anaerobe that made the grade.

    Science.gov (United States)

    Brazier, Jon S

    2012-04-01

    Unlike other anaerobic bacteria of clinical importance, Clostridium difficile has managed to enter into the realm of public awareness. Following the trail blazed by methicillin-resistant Staphylococcus aureus (MRSA), C. difficile has made the transition from being an obscure anaerobic bacterium, mainly of interest to specialist anaerobic microbiologists, to that of an infamous "superbug" responsible for outbreaks of hospital-acquired infection that commonly result in serious disease and death. This report picks out key moments, particularly in the UK, which tracked the rise in both the public and political awareness of this organism. PMID:22293217

  3. Combined Anaerobic-Aerobic Bacterial Degradation of Dyes

    OpenAIRE

    R. Wilfred Sugumar; Sandhya Sadanandan

    2010-01-01

    Wastewaters from the dye baths of a non-formal textile-dyeing unit containing C.I. Acid Orange 7 and C.I. Reactive Red 2 were subjected to degradation in a sequential anaerobic-aerobic treatment process based on mixed culture of bacteria. The technical samples of the dyestuffs and the dye bath wastes were treated in an anaerobic reactor, using an adapted mixed culture of anaerobic microorganisms. The dyestuffs were biotransformed into colourless substituted amine metabolites in the reactor. T...

  4. ANAEROBIC MEMBRANE BIOREACTORS FOR DOMESTIC WASTEWATER TREATMENT. PRELIMINARY STUDY

    Directory of Open Access Journals (Sweden)

    Luisa Vera

    2014-12-01

    Full Text Available The operation of submerged anaerobic membrane bioreactors (SAnMBRs for domestic wastewaters treatment was studied in laboratory scale, with the objective to define sustainable filtration conditions of the suspensions along the process. During continuous experiments, the organic matter degradation by anaerobic way showed an average DQOT removal of 85% and 93%. Indeed, the degradation generated biogas after 12 days of operation and its relative methane composition was of 60% after 25 days of operation. Additionally, the comparison between membrane bioreactors (MBRs performance in aerobic and anaerobic conditions in filterability terms, reported that both systems behave similarly once reached the stationary state.

  5. Electron beam/biological processing of anaerobic and aerobic sludge

    International Nuclear Information System (INIS)

    Besides common chemical and biological methods, the radiation technology is a promising way of sludge treatment. The paper describes possibilities of combined accelerated electrons/biological processing of both anaerobic and aerobic sludge. Besides one-shot experiments, experimental reactors for the simulation of anaerobic processes have been used. Main effort has been aimed to decrease organic compounds concentration and overall volume of solids, to improve some physico-chemical parameters of sludge, to validate hygienisation effects of the ionising radiation, and in the case of anaerobic sludge, to increase the volume of the produced biogas. Positive effects of the electron beam processing have been observed on all previously named parameters. (author)

  6. Fate of 17β-Estradiol as a model estrogen in source separated urine during integrated chemical P recovery and treatment using partial nitritation-anammox process.

    Science.gov (United States)

    Huang, Pei; Mukherji, Sachiyo T; Wu, Sha; Muller, James; Goel, Ramesh

    2016-10-15

    Recently, research on source separation followed by the treatment of urine and/or resource recovery from human urine has shown promise as an emerging management strategy. Despite contributing only 1% of the total volume of wastewater, human urine contributes about 80% of the nitrogen, 70% of the potassium, and up to 50% of the total phosphorus in wastewater. It is also a known fact that many of the micropollutants, especially selected estrogens, get into municipal wastewater through urine excretion. In this research, we investigated the fate of 17β-estradiol (E2) as a model estrogen during struvite precipitation from synthetic urine followed by the treatment of urine using a partial nitritation-anammox (PN/A) system. Single-stage and two-stage suspended growth PN/A configurations were used to remove the nitrogen in urine after struvite precipitation. The results showed an almost 95% phosphorous and 5% nitrogen recovery/removal from the synthetic urine due to struvite precipitation. The single and two stage PN/A processes were able to remove around 50% and 75% of ammonia and nitrogen present in the post struvite urine solution, respectively. After struvite precipitation, more than 95% of the E2 remained in solution and the transformation of E2 to E1 happened during urine storage. Most of the E2 removal that occurred during the PN/A process was due to sorption on the biomass and biodegradation (transformation of E2 to E1, and slow degradation of E1 to other metabolites). These results demonstrate that a combination of chemical and biological unit processes will be needed to recover and manage nutrients in source separated urine. PMID:27566951

  7. Systematic design of membership functions for fuzzy-logic control: A case study on one-stage partial nitritation/anammox treatment systems.

    Science.gov (United States)

    Boiocchi, Riccardo; Gernaey, Krist V; Sin, Gürkan

    2016-10-01

    A methodology is developed to systematically design the membership functions of fuzzy-logic controllers for multivariable systems. The methodology consists of a systematic derivation of the critical points of the membership functions as a function of predefined control objectives. Several constrained optimization problems corresponding to different qualitative operation states of the system are defined and solved to identify, in a consistent manner, the critical points of the membership functions for the input variables. The consistently identified critical points, together with the linguistic rules, determine the long term reachability of the control objectives by the fuzzy logic controller. The methodology is highlighted using a single-stage side-stream partial nitritation/Anammox reactor as a case study. As a result, a new fuzzy-logic controller for high and stable total nitrogen removal efficiency is designed. Rigorous simulations are carried out to evaluate and benchmark the performance of the controller. The results demonstrate that the novel control strategy is capable of rejecting the long-term influent disturbances, and can achieve a stable and high TN removal efficiency. Additionally, the controller was tested, and showed robustness, against measurement noise levels typical for wastewater sensors. A feedforward-feedback configuration using the present controller would give even better performance. In comparison, a previously developed fuzzy-logic controller using merely expert and intuitive knowledge performed worse. This proved the importance of using a systematic methodology for the derivation of the membership functions for multivariable systems. These results are promising for future applications of the controller in real full-scale plants. Furthermore, the methodology can be used as a tool to help systematically design fuzzy logic control applications for other biological processes. PMID:27390035

  8. Combined electrical-alkali pretreatment to increase the anaerobic hydrolysis rate of waste activated sludge during anaerobic digestion

    International Nuclear Information System (INIS)

    Highlights: • Combined electrical-alkali pretreatment for improving sludge anaerobic digestion was proposed. • Combined process enhanced the cell lysis, biopolymers releases, and thus sludge disintegration. • Increased solubilization of sludge increased the anaerobic hydrolysis rate. • Increased solubilization does not always induce an improved anaerobic digestion efficiency. - Abstract: Pretreatment can be used prior to anaerobic digestion to improve the efficiency of waste activated sludge (WAS) digestion. In this study, electrolysis and a commonly used pretreatment method of alkaline (NaOH) solubilization were integrated as a pretreatment method for promoting WAS anaerobic digestion. Pretreatment effectiveness of combined process were investigated in terms of disintegration degree (DDSCOD), suspended solids (TSS and VSS) removals, the releases of protein (PN) and polysaccharide (PS), and subsequent anaerobic digestion as well as dewaterability after digestion. Electrolysis was able to crack the microbial cells trapped in sludge gels and release the biopolymers (PN and PS) due to the cooperation of alkaline solubilization, enhancing the sludge floc disintegration/solubilization, which was confirmed by scanning electron microscopy (SEM) analysis. Biochemical methane potential (BMP) assays showed the highest methane yield was achieved with 5 V plus pH 9.2 pretreatment with up to 20.3% improvement over the non-pretreated sludge after 42 days of mesophilic operation. In contrast, no discernible improvements on anaerobic degradability were observed for the rest of pretreated sludges, probably due to the overmuch leakage of refractory soluble organics, partial chemical mineralization of solubilized compounds and sodium inhibition. The statistical analysis further indicated that increased solubilization induced by electrical-alkali pretreatment increased the first-order anaerobic hydrolysis rate (khyd), but had no, or very slight enhancement on WAS ultimate

  9. Characteristics, Process Parameters, and Inner Components of Anaerobic Bioreactors

    Directory of Open Access Journals (Sweden)

    Awad Abdelgadir

    2014-01-01

    Full Text Available The anaerobic bioreactor applies the principles of biotechnology and microbiology, and nowadays it has been used widely in the wastewater treatment plants due to their high efficiency, low energy use, and green energy generation. Advantages and disadvantages of anaerobic process were shown, and three main characteristics of anaerobic bioreactor (AB, namely, inhomogeneous system, time instability, and space instability were also discussed in this work. For high efficiency of wastewater treatment, the process parameters of anaerobic digestion, such as temperature, pH, Hydraulic retention time (HRT, Organic Loading Rate (OLR, and sludge retention time (SRT were introduced to take into account the optimum conditions for living, growth, and multiplication of bacteria. The inner components, which can improve SRT, and even enhance mass transfer, were also explained and have been divided into transverse inner components, longitudinal inner components, and biofilm-packing material. At last, the newly developed special inner components were discussed and found more efficient and productive.

  10. Nitrification and denitrification gene abundances in swine wastewater anaerobic lagoons

    Science.gov (United States)

    Although anaerobic lagoons are used globally for livestock waste treatment, their detailed microbial cycling of nitrogen is only beginning to become understood. Within this cycling, nitrification can be performed by organisms which produce the enzyme ammonia monooxygenase (AMO). For denitrification,...

  11. HIGH-RATE ANAEROBIC TREATMENT OF ALCOHOLIC WASTEWATERS

    Directory of Open Access Journals (Sweden)

    Florencio L.

    1997-01-01

    Full Text Available Modern high-rate anaerobic wastewater treatment processes are rapidly becoming popular for industrial wastewater treatment. However, until recently stable process conditions could not be guaranteed for alcoholic wastewaters containing higher concentrations of methanol. Although methanol can be directly converted into methane by methanogens, under specific conditions it can also be converted into acetate and butyrate by acetogens. The accumulation of volatile fatty acids can lead to reactor instability in a weakly buffered reactor. Since this process was insufficiently understood, the application of high-rate anaerobic reactors was highly questionable. This research investigated the environmental factors that are of importance in the predominance of methylotrophic methanogens over acetogens in a natural mixed culture during anaerobic wastewater treatment in upflow anaerobic sludge bed reactors. Technological and microbiological aspects were investigated. Additionally, the route by which methanol is converted into methane is also presented

  12. Anaerobic Fungi and Their Potential for Biogas Production

    Czech Academy of Sciences Publication Activity Database

    Dollhofer, V.; Podmirseg, S.M.; Callaghan, T. M.; Griffith, G.W.; Fliegerová, Kateřina

    2015-01-01

    Roč. 151, č. 1 (2015), s. 41-61. ISSN 0724-6145 Institutional support: RVO:67985904 Keywords : anaerobic fungi * Neocallimastigomycota * phylogeny Subject RIV: EE - Microbiology, Virology Impact factor: 1.657, year: 2014

  13. Anaerobic Dehalogenation of Hydroxylated Polychlorinated Biphenyls by Desulfitobacterium dehalogenans

    OpenAIRE

    Wiegel, Juergen; Zhang, Xiaoming; Wu, Qingzhong

    1999-01-01

    Ten years after reports on the existence of anaerobic dehalogenation of polychlorinated biphenyls (PCBs) in sediment slurries, we report here on the rapid reductive dehalogenation of para-hydroxylated PCBs (HO-PCBs), the excreted main metabolites of PCB in mammals, which can exhibit estrogenic and antiestrogenic activities in humans. The anaerobic bacterium Desulfitobacterium dehalogenans completely dehalogenates all flanking chlorines (chlorines in ortho position to the para-hydroxyl group) ...

  14. ANAEROBIC MEMBRANE BIOREACTORS FOR DOMESTIC WASTEWATER TREATMENT. PRELIMINARY STUDY

    OpenAIRE

    Luisa Vera; Ignacio Ruigómez; Enrique González; Paula Bodelón; Juan Rodríguez-Sevilla

    2014-01-01

    The operation of submerged anaerobic membrane bioreactors (SAnMBRs) for domestic wastewaters treatment was studied in laboratory scale, with the objective to define sustainable filtration conditions of the suspensions along the process. During continuous experiments, the organic matter degradation by anaerobic way showed an average DQOT removal of 85% and 93%. Indeed, the degradation generated biogas after 12 days of operation and its relative methane composition was of 60% after 25 days of o...

  15. Modeling for Anaerobic Fixed-Bed Biofilm Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B. Y. M.; Pfeffer, J. T.

    1989-06-01

    The specific objectives of this research were: 1. to develop an equilibrium model for chemical aspects of anaerobic reactors; 2. to modify the equilibrium model for non-equilibrium conditions; 3. to incorporate the existing biofilm models into the models above to study the biological and chemical behavior of the fixed-film anaerobic reactors; 4. to experimentally verify the validity of these models; 5. to investigate the biomass-holding ability of difference packing materials for establishing reactor design criteria.

  16. The Role of Benzoate in Anaerobic Degradation of Terephthalate

    OpenAIRE

    Kleerebezem, Robbert; Pol, Look W. Hulshoff; Lettinga, Gatze

    1999-01-01

    The effects of acetate, benzoate, and periods without substrate on the anaerobic degradation of terephthalate (1,4-benzene-dicarboxylate) by a syntrophic methanogenic culture were studied. The culture had been enriched on terephthalate and was capable of benzoate degradation without a lag phase. When incubated with a mixture of benzoate and terephthalate, subsequent degradation with preference for benzoate was observed. Both benzoate and acetate inhibited the anaerobic degradation of terephth...

  17. Contribution of anaerobic energy expenditure to whole body thermogenesis

    OpenAIRE

    Scott, Christopher B

    2005-01-01

    Heat production serves as the standard measurement for the determination of energy expenditure and efficiency in animals. Estimations of metabolic heat production have traditionally focused on gas exchange (oxygen uptake and carbon dioxide production) although direct heat measurements may include an anaerobic component particularly when carbohydrate is oxidized. Stoichiometric interpretations of the ratio of carbon dioxide production to oxygen uptake suggest that both anaerobic and aerobic he...

  18. Olive mill wastewater anaerobically digested : phenolic compounds with antiradical activity

    OpenAIRE

    La Cara, Francesco; Ionata, Elena; Del Monaco, Giovanni; Marcolongo, Loredana; Gonçalves, Marta R.; Marques, I. P.

    2012-01-01

    The recovery of phenolic compounds, present in the olive fruits and its by-products, has been intensively studied by the antioxidant properties. Olive mill wastewater (OMW) is a phenolic-rich industrial effluent that can be advantageously valorized by the anaerobic digestion to the methane and agricultural fertilizer productions. The objective of this work was to evaluate the antiradical activity of OMW after anaerobic digestion in order to maximize the valorization of this type o...

  19. Application of natural zeolites in anaerobic digestion processes: A review

    OpenAIRE

    Montalvo, Silvio; Borja Padilla, Rafael; Sánchez, Enrique; Milán, Zhenia; Cortés, Isel; Rubia, M. Ángeles de la

    2012-01-01

    This paper reviews the most relevant uses and applications of zeolites in anaerobic digestion processes. The feasibility of using natural zeolites as support media for the immobilization of microorganisms in different high-rate reactor configurations (fixed bed, fluidized bed, etc.) is also reviewed. Zeolite, with its favorable characteristics for microorganism adhesion, has also been widely used as an ion exchanger for the removal of ammonium in anaerobic digestion due to the presence of Na ...

  20. Design considerations and operational performance of Anaerobic Digester: A Review

    OpenAIRE

    Muzaffar Ahmad Mir; Athar Hussain; Chanchal Verma

    2016-01-01

    Due to the decline in fossil fuel reservoirs, the researchers emphasized more on the production of biogas from organic waste. Producing the renewable energy from biodegradable waste helps to overcome the energy crisis and solid waste management, done by anaerobic digestion. Anaerobic digestion is controlled breakdown of organic matter into methane gas (60%), carbon dioxide (40%), trace components along with digested used as soil conditioner. However there is vast dearth of literature regardin...

  1. Contribution of anaerobic energy expenditure to whole body thermogenesis

    Directory of Open Access Journals (Sweden)

    Scott Christopher B

    2005-06-01

    Full Text Available Abstract Heat production serves as the standard measurement for the determination of energy expenditure and efficiency in animals. Estimations of metabolic heat production have traditionally focused on gas exchange (oxygen uptake and carbon dioxide production although direct heat measurements may include an anaerobic component particularly when carbohydrate is oxidized. Stoichiometric interpretations of the ratio of carbon dioxide production to oxygen uptake suggest that both anaerobic and aerobic heat production and, by inference, all energy expenditure – can be accounted for with a measurement of oxygen uptake as 21.1 kJ per liter of oxygen. This manuscript incorporates contemporary bioenergetic interpretations of anaerobic and aerobic ATP turnover to promote the independence of these disparate types of metabolic energy transfer: each has different reactants and products, uses dissimilar enzymes, involves different types of biochemical reactions, takes place in separate cellular compartments, exploits different types of gradients and ultimately each operates with distinct efficiency. The 21.1 kJ per liter of oxygen for carbohydrate oxidation includes a small anaerobic heat component as part of anaerobic energy transfer. Faster rates of ATP turnover that exceed mitochondrial respiration and that are supported by rapid glycolytic phosphorylation with lactate production result in heat production that is independent of oxygen uptake. Simultaneous direct and indirect calorimetry has revealed that this anaerobic heat does not disappear when lactate is later oxidized and so oxygen uptake does not adequately measure anaerobic efficiency or energy expenditure (as was suggested by the "oxygen debt" hypothesis. An estimate of anaerobic energy transfer supplements the measurement of oxygen uptake and may improve the interpretation of whole-body energy expenditure.

  2. Yield and Quality of Biogas from Anaerobic Fermentation of Grass

    OpenAIRE

    Poláček, Jan

    2014-01-01

    Biogas is generally considered as a renewable source of energy. In fact, however, it is biodegradable organic material, that makes this source of energy renewable. Biogas is, then, the final product of anaerobic fermentation of these materials. Because energetically the most valuable component of biogas is methane (CH4) its relative volume stands as the measure of biogas quality. The process of anaerobic fermentation was characterized in the first part of this thesis. Organic materials ar...

  3. Fermentation and Anaerobic Respiration by Rhodospirillum rubrum and Rhodopseudomonas capsulata

    OpenAIRE

    Schultz, J E; Weaver, P. F.

    1982-01-01

    Rhodospirillum rubrum and Rhodopseudomonas capsulata were able to grow anaerobically in the dark either by a strict mixed-acid fermentation of sugars or, in the presence of an appropriate electron acceptor, by an energy-linked anaerobic respiration. Both species fermented fructose without the addition of accessory oxidants, but required the initial presence of bicarbonate before fermentative growth could begin. Major products of R. rubrum fermentation were succinate, acetate, propionate, form...

  4. Evaluation of Fastidious Anaerobe Broth as a blood culture medium.

    OpenAIRE

    Ganguli, L. A.; Turton, L J; Tillotson, G S

    1982-01-01

    Three commercial blood culture media were compared with a freshly prepared cooked meat medium in tests to stimulate the recovery of small inocula of anaerobic and aerobic bacteria in routine blood cultures. The cooked meat medium gave the most reliable recovery and supported continued viability, whilst Fastidious Anaerobe Broth (LAB M) was a good alternative. Results with Southern Group thioglycollate and Difco Thiol were less satisfactory as delays in recovery and loss of viability occurred ...

  5. Anaerobes Wachstum von Corynebacterium glutamicum durch gemischte Säurefermentation

    OpenAIRE

    Michel, Andrea

    2014-01-01

    Corynebacterium glutamicum is able to grow under anaerobic conditions with nitrate aselectron acceptor, but only very low cell densities are attainable because of the toxic nitritethat cannot be efficiently metabolized by C. glutamicum. Furthermore it is known thatC. glutamicum is metabolically active under oxygen-free conditions and produces lactate,succinate, and acetate from glucose. However, fermentative anaerobic growth ofC. glutamicum has not been described, yet. In this work, the abili...

  6. Xylan degradation by the anaerobic bacterium Bacteroides xylanolyticus.

    OpenAIRE

    Schyns, P.J.Y.M.J.

    1997-01-01

    Plant cell walls are the major reservoir of fixed carbon in nature. The mineralization of the fiber material, the so called lignocellulosic complex, proceeds almost exclusively by microbial processes in both aerobic and anaerobic environments. In anaerobic microbial processes the energy of the plant polymers can be conserved in fermentation products. The valorization of agricultural waste plant materials can consist of low and high technological processes. These include the production of biog...

  7. Contribution of anaerobic energy expenditure to whole body thermogenesis

    OpenAIRE

    Scott Christopher B

    2005-01-01

    Abstract Heat production serves as the standard measurement for the determination of energy expenditure and efficiency in animals. Estimations of metabolic heat production have traditionally focused on gas exchange (oxygen uptake and carbon dioxide production) although direct heat measurements may include an anaerobic component particularly when carbohydrate is oxidized. Stoichiometric interpretations of the ratio of carbon dioxide production to oxygen uptake suggest that both anaerobic and a...

  8. Analysis and control of an anaerobic upflow Fixed bed bioreactor

    International Nuclear Information System (INIS)

    This paper presents the bifurcation analysis in an anaerobic upflow fixed bed bioreactor, which is an anaerobic digestion system useful for wastewater treatment. In the dynamic analysis part, the equilibrium points, linear stability and bifurcation curves are studied, focusing in the washout condition. For the self tuning regulator the parameter estimation and control law are designed, and an integral action is introduced in order to address the disturbances. The simulation studies show the improvement of the performance when a disturbance appears.

  9. Anaerobic-Aerobic Process for Microbial Degradation of Tetrabromobisphenol A

    OpenAIRE

    Ronen, Zeev; Abeliovich, Aharon

    2000-01-01

    Tetrabromobisphenol A (TBBPA) is a flame retardant that is used as an additive during manufacturing of plastic polymers and electronic circuit boards. Little is known about the fate of this compound in the environment. In the current study we investigated biodegradation of TBBPA, as well as 2,4,6-tribromophenol (TBP), in slurry of anaerobic sediment from a wet ephemeral desert stream bed contaminated with chemical industry waste. Anaerobic incubation of the sediment with TBBPA and peptone-try...

  10. Anaerobic digestion of organic solid waste for energy production

    OpenAIRE

    Nayono, Satoto Endar

    2009-01-01

    This study was carried out in order to evaluate the performance of anaerobic reactors treating OFMSW (organic fraction of municipal solid waste), especially in terms of its energy recovery, either by investigating the maximum organic loading rate or by co-digestion with other types of wastes for energy recovery. In order to reach the research purpose, several experiments such as characteristics examination of different organic solid wastes, which are potential substrates for anaerobic digestion.

  11. Increased Anaerobic Digestion Efficiency via the Use of Thermal Hydrolysis

    OpenAIRE

    Fraser, Kino Dwayne

    2010-01-01

    Waste sludge is frequently treated by anaerobic digestion to kill pathogens, generate methane gas and reduce odors so the sludge can be safely land applied. In an attempt to reduce sludge volumes and improve sludge dewatering properties, the use of thermal hydrolysis (TH), a sludge pretreatment method, has been adopted by numerous wastewater treatment plants, among them being the District of Columbia Water and Sewage Authority (DC WASA). The use of anaerobic digestion in collaboration wi...

  12. Identification of a conserved protein involved in anaerobic unsaturated fatty acid synthesis in Neiserria gonorrhoeae: implications for facultative and obligate anaerobes that lack FabA

    OpenAIRE

    Isabella, Vincent M.; Clark, Virginia L.

    2011-01-01

    Transcriptome analysis of the facultative anaerobe, Neisseria gonorrhoeae, revealed that many genes of unknown function were induced under anaerobic conditions. Mutation of one such gene, NGO1024, encoding a protein belonging to the 2-nitropropane dioxygenase-like superfamiliy of proteins, was found to result in an inability of gonococci to grow anaerobically. Anaerobic growth of an NG1024 mutant was restored upon supplementation with unsaturated fatty acids (UFA), but not with the saturated ...

  13. Clinical characteristics associated with mortality of patients with anaerobic bacteremia.

    Science.gov (United States)

    Umemura, Takumi; Hamada, Yukihiro; Yamagishi, Yuka; Suematsu, Hiroyuki; Mikamo, Hiroshige

    2016-06-01

    The presence of anaerobes in the blood stream is known to be associated with a higher rate of mortality. However, few prognostic risk factor analyses examining whether a patient's background characteristics are associated with the prognosis have been reported. We performed a retrospective case-controlled study to assess the prognostic factors associated with death from anaerobic bacteremia. Seventy-four patients with anaerobic bacteremia were treated between January 2005 and December 2014 at Aichi Medical University Hospital. The clinical information included drug susceptibility was used for analysis of prognostic factors for 30-day mortality. Multivariate logistic analyses revealed an association between the 30-day mortality rate and malignancy (OR: 3.64, 95% CI: 1.08-12.31) and clindamycin resistance (OR: 7.93, 95% CI: 2.33-27.94). The result of Kaplan-Meier analysis of mortality showed that the 30-day survival rate was 83% in clindamycin susceptible and 38.1% in clindamycin resistant anaerobes causing bacteremia. The result of log-rank test also showed that susceptibility to clindamycin affected mortality (P < 0.001). Our results indicated that malignancy and clindamycin susceptibility could be used to identify subgroups of patients with anaerobic bacteremia with a higher risk of 30-day mortality. The results of this study are important for the early and appropriate management of patients with anaerobic bacteremia. PMID:26903282

  14. Reconstructing the mosaic glycolytic pathway of the anaerobic eukaryote Monocercomonoides.

    Science.gov (United States)

    Liapounova, Natalia A; Hampl, Vladimir; Gordon, Paul M K; Sensen, Christoph W; Gedamu, Lashitew; Dacks, Joel B

    2006-12-01

    All eukaryotes carry out glycolysis, interestingly, not all using the same enzymes. Anaerobic eukaryotes face the challenge of fewer molecules of ATP extracted per molecule of glucose due to their lack of a complete tricarboxylic acid cycle. This may have pressured anaerobic eukaryotes to acquire the more ATP-efficient alternative glycolytic enzymes, such as pyrophosphate-fructose 6-phosphate phosphotransferase and pyruvate orthophosphate dikinase, through lateral gene transfers from bacteria and other eukaryotes. Most studies of these enzymes in eukaryotes involve pathogenic anaerobes; Monocercomonoides, an oxymonad belonging to the eukaryotic supergroup Excavata, is a nonpathogenic anaerobe representing an evolutionarily and ecologically distinct sampling of an anaerobic glycolytic pathway. We sequenced cDNA encoding glycolytic enzymes from a previously established cDNA library of Monocercomonoides and analyzed the relationships of these enzymes to those from other organisms spanning the major groups of Eukaryota, Bacteria, and Archaea. We established that, firstly, Monocercomonoides possesses alternative versions of glycolytic enzymes: fructose-6-phosphate phosphotransferase, both pyruvate kinase and pyruvate orthophosphate dikinase, cofactor-independent phosphoglycerate mutase, and fructose-bisphosphate aldolase (class II, type B). Secondly, we found evidence for the monophyly of oxymonads, kinetoplastids, diplomonads, and parabasalids, the major representatives of the Excavata. We also found several prokaryote-to-eukaryote as well as eukaryote-to-eukaryote lateral gene transfers involving glycolytic enzymes from anaerobic eukaryotes, further suggesting that lateral gene transfer was an important factor in the evolution of this pathway for denizens of this environment. PMID:17071828

  15. Characterizing the anaerobic response of Chlamydomonas reinhardtii by quantitative proteomics.

    Science.gov (United States)

    Terashima, Mia; Specht, Michael; Naumann, Bianca; Hippler, Michael

    2010-07-01

    The versatile metabolism of the green alga Chlamydomonas reinhardtii is reflected in its complex response to anaerobic conditions. The anaerobic response is also remarkable in the context of renewable energy because C. reinhardtii is able to produce hydrogen under anaerobic conditions. To identify proteins involved during anaerobic acclimation as well as to localize proteins and pathways to the powerhouses of the cell, chloroplasts and mitochondria from C. reinhardtii in aerobic and anaerobic (induced by 8 h of argon bubbling) conditions were isolated and analyzed using comparative proteomics. A total of 2315 proteins were identified. Further analysis based on spectral counting clearly localized 606 of these proteins to the chloroplast, including many proteins of the fermentative metabolism. Comparative quantitative analyses were performed with the chloroplast-localized proteins using stable isotopic labeling of amino acids ([(13)C(6)]arginine/[(12)C(6)]arginine in an arginine auxotrophic strain). The quantitative data confirmed proteins previously characterized as induced at the transcript level as well as identified several new proteins of unknown function induced under anaerobic conditions. These proteins of unknown function provide new candidates for further investigation, which could bring insights for the engineering of hydrogen-producing alga strains. PMID:20190198

  16. [Anaerobic digestion of animal manure contaminated by tetracyclines].

    Science.gov (United States)

    Tong, Zi-Lin; Liu, Yuan-Lu; Hu, Zhen-Hu; Yuan, Shou-Jun

    2012-03-01

    Anaerobic digestion of pig manure spiked with tetracycline (TC) and chlortetracycline (CTC) and the degradation of the two antibiotics during the anaerobic digestion at 35 degrees C were investigated. The results indicate that propionate was the main volatile fatty acid produced during the anaerobic digestion followed by acetate. Compared with the CTC addition, TC + CTC addition showed obvious inhibitory effect on the hydrolysis and acidification of easily digestible organic components of pig manure. The cumulative methane production of TC, CTC, TC + CTC and CK2 during anaerobic digestion was 386.4 mL, 406.0 mL, 412.1 mL and 464.6 mL, respectively. Degradation of TC and CTC followed the first-order kinetic equation. The half-life of TC and CTC was 14-18 days and 10 days, respectively. After the treatment of 45-day anaerobic digestion, the degradation efficiency of TC was 88.6%-91.6% with 97.7%-98.2% of CTC. Therefore, anaerobic digestion shows the benefit on the management of animal manures contaminated by tetracyclines. PMID:22624404

  17. Hydrogen Biogeochemistry in Anaerobic and Photosynthetic Ecosystems

    Science.gov (United States)

    Hoehler, Tori M.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    The simple biochemistry of molecular hydrogen is central to a large number of microbial processes, affecting the interaction of organisms with each other and with the environment. In anoxic sediments, a great majority of microbial redox processes involve hydrogen as a reactant, product or potential by-product. Accordingly, the energetics (thermodynamics) of each of these processes is affected by variations in local H2 concentrations. It has long been established that this effect is important in governing microbe-microbe interactions and there are multiple demonstrations that "interspecies hydrogen transfer" can alter the products of, inhibit/stimulate, or even reverse microbial metabolic reactions. In anoxic sediments, H2 concentrations themselves are thought to be controlled by the thermodynamics of the predominant H2-consuming microbial process. In sediments from Cape Lookout Bight, this relationship quantitatively describes the co-variation of H2 concentrations with temperature (for methanogens and sulfate reducers) and with sulfate concentration (for sulfate reducers). The quantitative aspect is import= for two reasons: 1) it permits the modeling of H2-sensitive biogeochemistry, such as anaerobic methane oxidation or pathways of organic matter remineralization, as a function of environmental controls; 2) for such a relationship to be observed requires that intracellular biochemistry and bioenergetics are being directly expressed in a component of the extracellular medium. H2 could therefore be utilized a non-invasive probe of cellular energetic function in intact microbial ecosystems. Based on the latter principle we have measured down-core profiles of H2 and other relevant physico-chemical parameters in order to calculate the metabolic energy yields (DG) that support microbial metabolism in Cape Lookout Bight sediments. Methanogens in this system apparently function with energy yields significantly smaller than the minimum requirements suggested by pure

  18. Anaerobic metabolism in the N-limited green alga Selenastrum minutum. 3. Alanine is the product of anaerobic ammonium assimilation

    International Nuclear Information System (INIS)

    The authors have determined the flow of 15N into free amino acids of the N-limited green alga Selenastrum minutum (Naeg.) Collins after addition of 15NH4+ to aerobic or anaerobic cells. Under aerobic conditions, only a small proportion of the N assimilated was retained in the free amino acid pool. However, under anaerobic conditions almost all assimilated NH4+ accumulates in alanine. This is a unique feature of anaerobic NH4+ assimilation. The pathway of carbon flow to alanine results in the production of ATP and reductant which matches exactly the requirements of NH4+ assimilation. Alanine synthesis is therefore an excellent strategy to maintain energy and redox balance during anaerobic NH4+ assimilation

  19. Effect of methanogenic substrates on anaerobic oxidation of methane and sulfate reduction by an anaerobic methanotrophic enrichment

    OpenAIRE

    Meulepas, R.J.W.; Jagersma, C.G.; Khadem, A.F.; Buisman, C.J.N.; Stams, A.J.M.; Lens, P. N. L.

    2010-01-01

    Anaerobic oxidation of methane (AOM) coupled to sulfate reduction (SR) is assumed to be a syntrophic process, in which methanotrophic archaea produce an interspecies electron carrier (IEC), which is subsequently utilized by sulfate-reducing bacteria. In this paper, six methanogenic substrates are tested as candidate-IECs by assessing their effect on AOM and SR by an anaerobic methanotrophic enrichment. The presence of acetate, formate or hydrogen enhanced SR, but did not inhibit AOM, nor did ...

  20. Anaerobic digestion of slaughterhouse by-products

    International Nuclear Information System (INIS)

    Anaerobic digestion of animal by-products was investigated in batch and semi-continuously fed, reactor experiments at 55 oC and for some experiments also at 37 oC. Separate or mixed by-products from pigs were tested. The methane potential measured by batch assays for meat- and bone flour, fat, blood, hair, meat, ribs, raw waste were: 225, 497, 487, 561, 582, 575, 359, 619 dm3 kg-1 respectively, corresponding to 50-100% of the calculated theoretical methane potential. Dilution of the by-products had a positive effect on the specific methane yield with the highest dilutions giving the best results. High concentrations of long-chain fatty acids and ammonia in the by-products were found to inhibit the biogas process at concentrations higher than 5 g lipids dm-3 and 7 g N dm-3 respectively. Pretreatment (pasteurization: 70 oC, sterilization: 133 oC, and alkali hydrolysis (NaOH) had no effect on achieved methane yields. Mesophilic digestion was more stable than thermophilic digestion, and higher methane yield was noticed at high waste concentrations. The lower yield at thermophilic temperature and high waste concentration was due to ammonia inhibition. Co-digestion of 5% pork by-products mixed with pig manure at 37 oC showed 40% higher methane production compared to digestion of manure alone.