Effect of Shear Stress on Detachment in Biofilm Reactor under Low C/N Ratio

2014 ◽  
Vol 955-959 ◽  
pp. 681-686 ◽  
Author(s):  
Yin Jun ◽  
Heng Juan Xu
Keyword(s):  
Shear Stress ◽  
Relative Abundance ◽  
Oxidation Rate ◽  
Mixed Population ◽  
Biofilm Reactor ◽  
Hydrodynamic Condition ◽  
Ammonium Oxidation ◽  
Constant Flow ◽  
Nitrification Process ◽  
Pyrosequencing Analysis

The aim of this study is to evaluate the effect of shear stress on detachment and nitrification process in a mixed-population biofilm. The biofilm was grown under constant flow condition with low C/N ratio. During the experiment, ammonium oxidation rate reached above 99%. Sloughing events happened mainly under constant hydrodynamic condition. Detachment experiment showed that it’s not possible to control the occurrence of sloughing events by controlling shear stress. Pyrosequencing analysis of the biofilm showed that Proteobacteria and Bacteroidetes were the two most abundant phyla, but detachment would influence the relative abundance of AOB and NOB in biofilm to affect the nitrification process.

scholarly journals Model-based analysis of microbial consortia and microbial products in an anammox biofilm reactor

2018 ◽  
Vol 77 (7) ◽  
pp. 1951-1959 ◽  
Author(s):  
M. Azari ◽  
A. V. Le ◽  
M. Lübken ◽  
M. Denecke
Keyword(s):  
Relative Abundance ◽  
Inorganic Nitrogen ◽  
Biofilm Reactor ◽  
Microbial Consortia ◽  
Nitrifying Bacteria ◽  
Anammox Bacteria ◽  
Ammonium Oxidation ◽  
Leachate Treatment ◽  
Model Based ◽  
Microbial Products

Abstract A mathematical model for a granular biofilm reactor for leachate treatment was validated by long-term measured data to investigate the mechanisms and drivers influencing biological nitrogen removal and microbial consortia dynamics. The proposed model, based on Activated Sludge Model (ASM1), included anaerobic ammonium oxidation (anammox), nitrifying and heterotrophic denitrifying bacteria which can attach and grow on granular activated carbon (GAC) particles. Two kinetic descriptions for the model were proposed: with and without soluble microbial products (SMP) and extracellular polymeric substance (EPS). The model accuracy was checked using recorded total inorganic nitrogen concentrations in the effluent and estimated relative abundance of active bacteria using quantitative fluorescence in-situ hybridization (qFISH). Results suggested that the model with EPS kinetics fits better for the relative abundance of anammox bacteria and nitrifying bacteria compared to the model without EPS. The model with EPS and SMP confirms that the growth and existence of heterotrophs in anammox biofilm systems slightly increased due to including the kinetics of SMP production in the model. During the one-year simulation period, the fractions of autotrophs and EPS in the biomass were almost stable but the fraction of heterotrophs decreased which is correlated with the reduction in nitrogen surface loading on the biofilm.

scholarly journals Enhanced Nitrogen Removal from Domestic Wastewater by Partial-Denitrification/Anammox in an Anoxic/Oxic Biofilm Reactor

Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 109
Author(s):  
Yu Huang ◽  
Yongzhen Peng ◽  
Donghui Huang ◽  
Jiarui Fan ◽  
Rui Du
Keyword(s):  
Nitrogen Removal ◽  
Oxygen Demand ◽  
Domestic Wastewater ◽  
Biofilm Reactor ◽  
Anammox Bacteria ◽  
Stable Operation ◽  
Ammonium Oxidation ◽  
N Accumulation ◽  
Carbon Demand ◽  
Oxidation Efficiency

A partial-denitrification coupling with anaerobic ammonium oxidation (anammox) process (PD/A) in a continuous-flow anoxic/oxic (A/O) biofilm reactor was developed to treat carbon-limited domestic wastewater (ammonia (NH4+-N) of 55 mg/L and chemical oxygen demand (COD) of 148 mg/L in average) for about 200 days operation. Satisfactory NH4+-N oxidation efficiency above 95% was achieved with rapid biofilm formation in the aerobic zone. Notably, nitrite (NO2−-N) accumulation was observed in the anoxic zone, mainly due to the insufficient electron donor for complete nitrate (NO3−-N) reduction. The nitrate-to-nitrite transformation ratio (NTR) achieved was as high as 64.4%. After the inoculation of anammox-enriched sludge to anoxic zones, total nitrogen (TN) removal was significantly improved from 37.3% to 78.0%. Anammox bacteria were effectively retained in anoxic biofilm utilizing NO2−-N produced via the PD approach and NH4+-N in domestic wastewater, with the relative abundance of 5.83% for stable operation. Anammox pathway contributed to TN removal by a high level of 38%. Overall, this study provided a promising method for mainstream nitrogen removal with low energy consumption and organic carbon demand.

Identification of inhibitory effects of industrial effluents on nitrification

2009 ◽  
Vol 59 (4) ◽  
pp. 797-803 ◽  
Author(s):  
A. Žgajnar Gotvajn ◽  
J. Zagorc-Končan
Keyword(s):  
Oxygen Consumption ◽  
Activated Sludge ◽  
Landfill Leachate ◽  
Industrial Effluents ◽  
Tannery Effluent ◽  
Ammonium Oxidation ◽  
Pharmaceutical Wastewater ◽  
Heterotrophic Microorganisms ◽  
Nitrification Process ◽  
The Impact

The aim of our work was to determine the extent of inhibition of oxygen consumption by activated sludge for carbonaceous and ammonium oxidation (ISO 8192 2007) for various wastewaters. We have selected several types of wastewaters different in their origin and composition: pharmaceutical wastewater, tannery wastewater and municipal landfill leachate. To confirm results of toxicity testing, additional ready biodegradability assessment test with measurement of oxygen consumption was accomplished to indicate the impact of effluents to nitrification process. Pharmaceutical wastewater was toxic to activated sludge, but it inhibited heterotrophic microorganisms much more than nitrifying ones. Biodegradability testing confirmed low impact to nitrification by high, non-suppressed oxygen consumption for nitrification process. Tannery effluent inhibited nitrification significantly (180 min EC50 was 57 vol.%), but it did not affect heterotrophic microorganisms. Landfill leachate was very toxic to heterotrophic microorganisms (180 min EC50 was 3 vol.%), while it inhibited nitrification less (180 min EC50 was 24 vol.%). Presented research confirmed that the investigated experimental method is a reliable one for detection of occurrence of substances inhibiting nitrification in different industrial effluents. With regular monitoring of inhibitory impact biological treatment process upsets could be avoided and treatment optimised.

Effect of pH, substrate and free nitrous acid concentrations on ammonium oxidation rate

2012 ◽  
Vol 124 ◽  
pp. 478-484 ◽  
Author(s):  
E. Jiménez ◽  
J.B. Giménez ◽  
A. Seco ◽  
J. Ferrer ◽  
J. Serralta
Keyword(s):  
Oxidation Rate ◽  
Nitrous Acid ◽  
Ammonium Oxidation ◽  
Free Nitrous Acid ◽  
Effect Of Ph

Enhancing Ammonium Oxidation Fluxes and Nitritation Efficiencies in MABRs: A Modeling Study

2022 ◽  
Author(s):  
Patricia Perez-Calleja ◽  
Emily Clements ◽  
Robert Nerenberg
Keyword(s):  
Membrane Surface ◽  
Biofilm Reactor ◽  
Ammonium Oxidation ◽  
Novel Technology ◽  
Dissolved O2 ◽  
Counter Diffusion ◽  
Modeling Study

The membrane aerated biofilm reactor (MABR) is a novel technology based on gas-supplying membranes that supply dissolved O2 (DO) to biofilms growing on the membrane surface. The counter-diffusion of dissolved...

scholarly journals Start-up of a full-scale partial nitritation-anammox MBBR without inoculum at Klagshamn WWTP

2020 ◽  
Vol 81 (9) ◽  
pp. 2033-2042 ◽  
Author(s):  
Ivelina Dimitrova ◽  
Agnieszka Dabrowska ◽  
Sara Ekström
Keyword(s):  
Nitrogen Removal ◽  
Removal Rate ◽  
Treatment Plant ◽  
Full Scale ◽  
Biofilm Reactor ◽  
Operating Conditions ◽  
Ex Situ ◽  
Ammonium Oxidation ◽  
Partial Nitritation ◽  
Start Up

Abstract Partial nitritation and anaerobic ammonium oxidation (PNA) is a useful process for the treatment of nitrogen-rich centrate from the dewatering of anaerobically digested sludge. A one-stage PNA moving bed biofilm reactor (MBBR) was started up without inoculum at Klagshamn wastewater treatment plant, southern Sweden. The reactor was designed to treat up to 200 kgN d−1, and heated dilution water was used during start-up. The nitrogen removal was >80% after 111 days of operation, and the nitrogen removal rate reached 1.8 gN m−2 d1 at 35 °C. The start-up period of the reactor was comparable to that of inoculated full-scale systems. The operating conditions of the system were found to be important, and online control of the free ammonia concentration played a crucial role. Ex situ batch activity tests were performed to evaluate process performance.

scholarly journals Nitrogen removal and microbial communities of a completely autotrophic nitrogen removal over nitrite (CANON) sequencing batch biofilm reactor (SBBR) at different inorganic carbon (IC) concentrations

2020 ◽  
Vol 81 (5) ◽  
pp. 1071-1079
Author(s):  
Caimeng Wang ◽  
Lirong Lei ◽  
Fangrui Cai ◽  
Youming Li
Keyword(s):  
Nitrogen Removal ◽  
Inorganic Nitrogen ◽  
Biofilm Reactor ◽  
Anammox Bacteria ◽  
Ammonium Oxidation ◽  
Sequencing Batch Biofilm Reactor ◽  
Microbial Analysis ◽  
Total Inorganic Nitrogen ◽  
Canon Process ◽  
Autotrophic Nitrogen Removal

Abstract In this study, the completely autotrophic nitrogen removal over nitrite (CANON) process was initiated in a sequencing batch biofilm reactor (SBBR). Then the reactor was operated under different IC/N ratios. The total inorganic nitrogen removal efficiency (TINRE) at IC/N ratios of 0.75, 1.0, 1.25, 1.5 and 2.0 were 37.0 ± 11.0%, 58.9 ± 10.2%, 73.9 ± 3.2%, 73.6 ± 1.8% and 72.6 ± 2.0%, respectively. The suitable range of IC/N ratio in this research is 1.25–2.0. The poor nitrogen removal performance at IC/N ratio of 0.75 was due to the lack of growth substrate for AnAOB and low pH simultaneously; at IC/N ratio of 1.0 this was because the substrate concentration was insufficient for fully recovering the AnAOB activities. Microbial analysis indicated that Nitrosomonas, Nitrospira and Candidatus Brocadia were the main ammonium oxidation bacteria (AOB), nitrite oxidation bacteria (NOB) and anammox bacteria (AnAOB), respectively. In addition, at IC ratios of 1.25 or higher, denitrification was promoted with the rise of IC/N ratio, which might be because the change of IC concentrations caused cell lysis of microorganisms and provided organic matter for denitrification.

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