scholarly journals Operational modifications for the development of nitrifying bacteria in a large-scale biological aerated filter and its impact on wastewater treatment

2018 ◽  
Vol 78 (8) ◽  
pp. 1704-1714 ◽  
Author(s):  
François-René Bourgeois ◽  
Frédéric Monette ◽  
Daniel G. Cyr
Keyword(s):  
Large Scale ◽  
Oxygen Demand ◽  
Bacterial Biofilm ◽  
Nitrifying Bacteria ◽  
Nitrification Rate ◽  
Total Biomass ◽  
Ammonia Oxidizing Bacteria ◽  
Operational Conditions ◽  
Nitrite Oxidizing Bacteria ◽  
Aerated Filter

Abstract To develop a better understanding for fixed biomass processes, the development of a nitrifying bacterial biofilm, as well as the performance of treatment during modifications to operational conditions of a full-scale submerged biological filter were examined. The development of the nitrifying biofilm was investigated at four depth levels (1, 2, 4 and 5 feet). The result of bacterial subpopulations analyzed by qPCR relative to the physico-chemical parameters of the wastewater during the various tests (sustained aeration, modified backwash parameters and inflow restriction) revealed an increase of the relative presence of nitrifying microorganisms throughout the biofilm (especially for nitrite oxidizing bacteria (NOB)), but this was not necessarily accompanied by a better nitrification rate. The highest observed nitrification rate was 49% of removal in the test cell during backwashing conditions, whereas the relative ammonia oxidizing bacteria (AOB) population was 0.032% and NOB was 0.008% of the total biomass collected. The highest percentage of nitrifying bacteria observed (0.034% AOB and 0.18% NOB) resulted in a nitrification rate of 21%. The treatment of organic matter determined by measuring the chemical and biochemical oxygen demand (COD, CBOD5) was improved.

Characterization of bacterial biofilm communities in tertiary treatment processes for wastewater reclamation and reuse

2008 ◽  
Vol 58 (5) ◽  
pp. 1023-1030 ◽  
Author(s):  
Tadashi Shoji ◽  
Shuichi Ochi ◽  
Masaaki Ozaki
Keyword(s):  
Urban Areas ◽  
Heterotrophic Bacteria ◽  
Bacterial Biofilm ◽  
Nitrifying Bacteria ◽  
Water Supply Systems ◽  
Ammonia Oxidizing Bacteria ◽  
Tertiary Treatment ◽  
Treatment Processes ◽  
Related Group ◽  
Biofilm Development

The concern with wastewater reuse as a sustainable water resource in urban areas has been growing. For the reclamation and distribution of wastewater, biofilm development deserves careful attention from the point of view of its promotion (e.g. biofiltration) and inhibition (e.g. clogging and hygiene problems). As the first step to control biofilm development, bacterial biofilm communities in tertiary treatment processes were characterized by using molecular biological methods. The result of clone library analysis showed that Nitrospirae-related (nitrite-oxydizing bacteria) and Acidobacteria-related (probably oligotrophic bacteria) groups were dominant. The ratio of the Nitrospirae-related group to the Acidobacteria-related group was associated with ammonia load, whereas other operational conditions (process, media, temperature, salt) did not clearly affect the phylum-level community or the dominant sequence of nitrifying bacteria. The result of real-time PCR also indicated that high ammonia load promotes the proliferation of nitrite- and ammonia-oxidizing bacteria. Regarding water supply systems, some researchers also have suggested the dominance of Nitrospirae- and Acidobacteria-related groups in biofilm formed on water distribution pipes. In tertiary wastewater treatment, therefore, it is concluded that oligotrophic and autotrophic bacteria are the dominant groups in biofilm samples because assimilable organic carbon is too poor to proliferate various heterotrophic bacteria.

Nitrogen removal from high organic loading wastewater in modified Ludzack–Ettinger configuration MBBR system

2015 ◽  
Vol 72 (8) ◽  
pp. 1274-1282 ◽  
Author(s):  
Mojtaba Torkaman ◽  
Seyed Mehdi Borghei ◽  
Sepehr Tahmasebian ◽  
Mohammad Reza Andalibi
Keyword(s):  
Loading Rate ◽  
Oxygen Demand ◽  
Biofilm Reactor ◽  
Denitrification Rate ◽  
Synthetic Wastewater ◽  
Organic Loading Rate ◽  
Nitrification Rate ◽  
Organic Loading ◽  
Operational Conditions ◽  
Aerobic Reactor

A moving bed biofilm reactor with pre-denitrification configuration was fed with a synthetic wastewater containing high chemical oxygen demand (COD) and ammonia. By changing different variables including ammonium and COD loading, nitrification rate in the aerobic reactor and denitrification rate in the anoxic reactor were monitored. Changing the influent loading was achieved via adjusting the inlet COD (956–2,096 mg/L), inlet ammonium (183–438 mg/L), and hydraulic retention time of the aerobic reactor (8, 12, and 18 hours). The overall organic loading rate was in the range of 3.60–17.37 gCOD/m2·day, of which 18.5–91% was removed in the anoxic reactor depending on the operational conditions. Considering the complementary role of the aerobic reactor, the overall COD removal was in the range 87.3–98.8%. In addition, nitrification rate increased with influent ammonium loading, the maximum rate reaching 3.05 gNH4/m2·day. One of the most important factors affecting nitrification rate was influent C:N entering the aerobic reactor, by increasing which nitrification rate decreased asymptotically. Nitrate removal efficiency in the anoxic reactor was also controlled by the inlet nitrate level entering the anoxic reactor. Furthermore, by increasing the nitrate loading rate from 0.91 to 3.49 gNO/m3·day, denitrification rate increased from 0.496 to 2.47 gNO/m3·day.

Predicting N2O emissions from nitrifying and denitrifying biofilms: a modeling study

2016 ◽  
Vol 75 (3) ◽  
pp. 530-538 ◽  
Author(s):  
Fabrizio Sabba ◽  
Cristian Picioreanu ◽  
Joshua P. Boltz ◽  
Robert Nerenberg
Keyword(s):  
Wastewater Treatment Plants ◽  
Oxygen Demand ◽  
N2o Emissions ◽  
Ammonia Oxidizing Bacteria ◽  
Biofilm Thickness ◽  
Biofilm Model ◽  
Suspended Growth ◽  
Nitrite Oxidizing Bacteria ◽  
The Difference ◽  
And Diffusion

Wastewater treatment plants can be significant sources of nitrous oxide (N2O), a potent greenhouse gas. While our understanding of N2O emissions from suspended-growth processes has advanced significantly, less is known about emissions from biofilm processes. Biofilms may behave differently due to their substrate gradients and microbial stratification. In this study, we used mathematical modeling to explore the mechanisms of N2O emissions from nitrifying and denitrifying biofilms. Our ammonia-oxidizing bacteria biofilm model suggests that N2O emissions from biofilm can be significantly greater than from suspended-growth systems. The driving factor is the diffusion of hydroxylamine, a nitrification intermediate, from the aerobic to the anoxic regions of the biofilm. The presence of nitrite-oxidizing bacteria further increased emissions. For denitrifying biofilms, our results suggest that emissions are generally greater than for suspended-growth systems. However, the magnitude of the difference depends on the bulk dissolved oxygen, chemical oxygen demand, and nitrate concentrations, as well as the biofilm thickness. Overall, the accumulation and diffusion of key intermediates, i.e. hydroxylamine and nitrite, distinguish biofilms from suspended-growth systems. Our research suggests that the mechanisms of N2O emissions from biofilms are much more complex than suspended-growth systems, and that emissions may be higher in many cases.

scholarly journals Pharmaceuticals and personal care products’ (PPCPs) impact on enriched nitrifying cultures

2021 ◽  
Author(s):  
Carla Lopez ◽  
Mac-Anthony Nnorom ◽  
Yiu Fai Tsang ◽  
Charles W. Knapp
Keyword(s):  
Wastewater Treatment Plants ◽  
Personal Care Products ◽  
Inhibitory Effect ◽  
Mitigation Measures ◽  
Nitrifying Bacteria ◽  
Ammonia Oxidizing Bacteria ◽  
Personal Care ◽  
Nitrite Oxidizing Bacteria ◽  
Inhibition Of Nitrification ◽  
The Impact

AbstractThe impact of pharmaceutical and personal care products (PPCPs) on the performance of biological wastewater treatment plants (WWTPs) has been widely studied using whole-community approaches. These contaminants affect the capacity of microbial communities to transform nutrients; however, most have neither honed their examination on the nitrifying communities directly nor considered the impact on individual populations. In this study, six PPCPs commonly found in WWTPs, including a stimulant (caffeine), an antimicrobial agent (triclosan), an insect repellent ingredient (N,N-diethyl-m-toluamide (DEET)) and antibiotics (ampicillin, colistin and ofloxacin), were selected to assess their short-term toxic effect on enriched nitrifying cultures: Nitrosomonas sp. and Nitrobacter sp. The results showed that triclosan exhibited the greatest inhibition on nitrification with EC50 of 89.1 μg L−1. From the selected antibiotics, colistin significantly affected the overall nitrification with the lowest EC50 of 1 mg L−1, and a more pronounced inhibitory effect on ammonia-oxidizing bacteria (AOB) compared to nitrite-oxidizing bacteria (NOB). The EC50 of ampicillin and ofloxacin was 23.7 and 12.7 mg L−1, respectively. Additionally, experimental data suggested that nitrifying bacteria were insensitive to the presence of caffeine. In the case of DEET, moderate inhibition of nitrification (<40%) was observed at 10 mg L−1. These findings contribute to the understanding of the response of nitrifying communities in presence of PPCPs, which play an essential role in biological nitrification in WWTPs. Knowing specific community responses helps develop mitigation measures to improve system resilience.

scholarly journals Development of Strategies for AOB and NOB Competition Supported by Mathematical Modeling in Terms of Successful Deammonification Implementation for Energy-Efficient WWTPs

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 562
Author(s):  
Mehdi Sharif Shourjeh ◽  
Przemysław Kowal ◽  
Xi Lu ◽  
Li Xie ◽  
Jakub Drewnowski
Keyword(s):  
Mathematical Modeling ◽  
Ammonia Oxidation ◽  
Current Knowledge ◽  
Microbial Interactions ◽  
Process Efficiency ◽  
Ammonia Oxidizing Bacteria ◽  
Operational Conditions ◽  
Novel Technologies ◽  
Anaerobic Ammonia Oxidation ◽  
Nitrite Oxidizing Bacteria

Novel technologies such as partial nitritation (PN) and partial denitritation (PDN) could be combined with the anammox-based process in order to alleviate energy input. The former combination, also noted as deammonification, has been intensively studied in a frame of lab and full-scale wastewater treatment in order to optimize operational costs and process efficiency. For the deammonification process, key functional microbes include ammonia-oxidizing bacteria (AOB) and anaerobic ammonia oxidation bacteria (AnAOB), which coexisting and interact with heterotrophs and nitrite oxidizing bacteria (NOB). The aim of the presented review was to summarize current knowledge about deammonification process principles, related to microbial interactions responsible for the process maintenance under varying operational conditions. Particular attention was paid to the factors influencing the targeted selection of AOB/AnAOB over the NOB and application of the mathematical modeling as a powerful tool enabling accelerated process optimization and characterization. Another reviewed aspect was the potential energetic and resources savings connected with deammonification application in relation to the technologies based on the conventional nitrification/denitrification processes.

Tailoring of highly efficient nitrifying biofilms in fluidized bed for ammonia-rich industrial wastewater treatment

2000 ◽  
Vol 42 (3-4) ◽  
pp. 357-362 ◽  
Author(s):  
S. Tsuneda ◽  
T. Miyoshi ◽  
Y. Aoi ◽  
A. Hirata
Keyword(s):  
Fluidized Bed ◽  
Industrial Wastewater ◽  
Domestic Wastewater ◽  
Nitrifying Bacteria ◽  
Nitrification Rate ◽  
Fish Analysis ◽  
Ammonia Oxidizing Bacteria ◽  
High Concentration ◽  
Stepwise Reduction ◽  
Biofilm Structure

We proposed two tailoring methods for efficient nitrifying biofilms on particles which are expected to be used in fluidized bed in nitrogen removal processes for industrial wastewaters. The first method was examined with gradual reduction of the hydraulic retention time in continuous feeding reactor to form biofilm with high nitrification ability. As a result, nitrification rate was successfully improved mainly due to acclimation of nitrifying bacteria to higher loading. The second tailoring method for nitrifying biofilm started with the biofilm which had been previously constructed in synthetic domestic wastewater containing high concentration of NH4+-N as well as various biodegradable organic compounds. Stepwise reduction of C/N ratio in inlet wastewater was performed during one month simultaneously with observation of microbial population dynamics in the biofilm using fluorescent in situ hybridization (FISH) analysis. As a result, this acclimation process promoted occupation of the biofilm by ammonia-oxidizing bacteria and resulted in making suitable biofilm structure for nitrification of ammonia-rich industrial wastewater. Moreover, it is confirmed that this new tailoring method greatly shortened required time to obtain nitrifying biofilms.

Community analysis of nitrifying bacteria in an advanced and compact Gappei-Johkasou by FISH and PCR-DGGE

2002 ◽  
Vol 46 (11-12) ◽  
pp. 105-111 ◽  
Author(s):  
Y. Ebie ◽  
M. Matsumura ◽  
N. Noda ◽  
S. Tsuneda ◽  
A. Hirata ◽  
...  
Keyword(s):  
Community Structure ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Quantitative Estimation ◽  
Community Analysis ◽  
Nitrifying Bacteria ◽  
Ammonia Oxidizing Bacteria ◽  
Load Fluctuation ◽  
New Information ◽  
Nitrite Oxidizing Bacteria ◽  
Gradient Gel Electrophoresis

Fluorescent in situ hybridization (FISH) method with 16S rRNA-targeted oligonucleotide probes was used for quantitative estimation of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in a Johkasou. Although the occupation ratios of AOB and NOB increased as nitrification progressed, about one month later, the occupation ratios decreased, despite showing good nitrification ability. Furthermore, even when urea was added to the feeding wastewater to raise the amount of T-N, the occupation ratios of both nitrifying bacteria remained constant. For further investigation, denaturing gradient gel electrophoresis (DGGE) was used to study the community structure of AOB in the Johkasou. As a result, DGGE band patterns and following sequence analysis revealed that the community structure of AOB was complicated and changed during this experiment. It was suggested that even if the occupation ratio of AOB to eubacteria was constant, the majorities of AOB were changed through temperature and load fluctuation. The combination of FISH and PCR-DGGE provides new information that was not available by conventional cultivationbased methods.

Bioelectrochemically-assisted nitrogen removal in osmotic membrane bioreactor

2020 ◽  
Author(s):  
You Wu ◽  
Yun Cai ◽  
Yu-Xiang Lu ◽  
Li-Min Zhang ◽  
Xiao-Li Yang ◽  
...  
Keyword(s):  
Microbial Community ◽  
Removal Efficiency ◽  
Nitrogen Removal ◽  
Membrane Bioreactor ◽  
Operation Mode ◽  
Oxygen Demand ◽  
Denitrifying Bacteria ◽  
Future Research ◽  
Ammonia Oxidizing Bacteria ◽  
Nitrite Oxidizing Bacteria

Abstract Nitrogen removal in osmosis membrane bioreactor (OMBR) is important to its applications but remains a challenge. In this study, a bioelectrochemically-assisted (BEA) operation was integrated into the feed side of OMBRs to enhance nitrogen removal, and sodium acetate was served as a draw solute and supplementary carbon source for the growth of denitrifying bacteria due to reversed-solute. The effects of operation mode and influent ammonium (NH4+) concentration were systematically examined. Compared to a conventional OMBR, the integrated BEA-OMBR achieved higher total nitrogen removal efficiency of 98.13%, and chemical oxygen demand removal efficiency of 95.83% with the influent NH4+-N concentration of 39 mg L−1. The sequencing analyses revealed that ammonia-oxidizing bacteria (0–0.04%), nitrite-oxidizing bacteria (0–0.16%), and denitrifying bacteria (1.98–8.65%) were in abundance of the microbial community in the feed/anode side of integrated BEA-OMBR, and thus BEA operation increased the diversity of the microbial community in OMBR. Future research will focus on improving nitrogen removal from a high ammonium strength wastewater by looping anolyte effluent to the cathode. These findings have demonstrated that BEA operation can be an effective approach to improve nitrogen removal in OMBRs toward sustainable wastewater treatment.

Pre-nitrification by encapsulated nitrifiers - a possibility for self-sufficient energy operation of domestic WWTPs

2003 ◽  
Vol 47 (11) ◽  
pp. 173-180
Author(s):  
M. Sievers ◽  
K.D. Vorlop ◽  
J. Hahne ◽  
M. Schlieker ◽  
S. Schäfer
Keyword(s):  
Energy Consumption ◽  
Oxygen Demand ◽  
High Energy ◽  
Anaerobic Sludge ◽  
Nitrification Rate ◽  
Treatment Efficiency ◽  
Nitrogen And Phosphorus ◽  
Operational Conditions ◽  
Sufficient Energy ◽  
New Process

The overall energy consumption of domestic wastewater treatment plants (WWTPs) increases with treatment efficiency. Approximately 30 to 45 kWh per people equivalent and year is mostly necessary for advanced nitrogen and phosphorus removal, while the aeration contains the main part of approximately 60%. A new process using encapsulated nitrifiers on gel lens beads is introduced to overcome the high energy consumption of aeration. A more selective nitrification process was found at a nitrification rate of between 50 and 60 mg nitrogen per hour and litre reaction volume corresponding to a hydraulic retention time (HRT) of about 30 to 60 minutes while the soluble Chemical Oxygen Demand (COD) removal could be less than 30% depending on operational conditions of the bio-reactor. The latter enables internal use of wastewater's COD for a post denitrification. For the new process the energy consumption as well as total volume of bio-reactor are much less (approximately 30 to 50% for both) than conventional processes due to the low sludge age for COD and nitrate removal and the avoidance of internal wastewater recycle. Therefore, self-sufficient energy operation of domestic WWTPs operating with advanced treatment efficiency could become possible, if energy recovery by anaerobic sludge digestion is included.

In situ analysis of nitrifying bacteria in sewage treatment plants

1996 ◽  
Vol 34 (1-2) ◽  
pp. 237-244 ◽  
Author(s):  
Michael Wagner ◽  
Gabriele Rath ◽  
Hans-Peter Koops ◽  
Janine Flood ◽  
Rudolf Amann
Keyword(s):  
Activated Sludge ◽  
Sewage Treatment ◽  
Nitrifying Bacteria ◽  
Ammonia Oxidizing Bacteria ◽  
Microbiological Methods ◽  
Nitrite Oxidizing Bacteria ◽  
Identification Technique ◽  
Engineered Systems ◽  
Simultaneous Identification

Autotrophic microbial nitrification is the key process in the removal of ammonia from wastewater. To avoid the limitations of traditional microbiological methods an in situ identification technique for ammonia- and nitrite-oxidizing bacteria was developed. Based on comparative sequence analyses we designed a collection of 16S ribosomal RNA-targeted oligonucleotide probes for all validly described members of the genusNitrobacter . Whole cell hybridizations of target and reference cells with fluorescent probe derivatives were used to determine the optimal hybridization stringency for each of the probes. These probes were applied together with a recently developed probe for important members of the genus Nitrosomonas for simultaneous identification of ammonia- and nitrite-oxidizing bacteria in natural and engineered systems. Ammonia-oxidizing bacteria were identified in situ in river water, epiphytic biofilms from eutrophic wetlands, oligotrophic biofilms, a nitrifying trickling filter biofilm as well as in all analyzed nitrifying activated sludge samples. In none of these samples could Nitrobacter cells be detected in situ. However, all hitherto describedNitrobacter species and a strain of Nitrobacter sp. isolated from one of the analyzed nitrifying activated sludge samples showed bright hybridization signals with all Nitrobacter specific probes. Possible reasons for the absence of in situ detectable Nitrobacter cells are discussed.

Sign in / Sign up

Export Citation Format

Share Document