Study on De-Nitrification of Improved Step-Feed Progress

Improved step-feed de-nitrification progress combined with biological fluidized bed was introduced in this study. The progress had good performance and capacity of de-nitrification and organic matter. The experiment result showed that the de-nitrification efficiency of the improved biological fluidized bed with step-feed process was higher than the fluidized bed A/O process under the same water quality and the operating conditions. When the influent proportion of each segment was equal, the system showed good nitrogen removal efficiency with the change of influent C/N ratio, HRT and sludge return ratio. The removal rate of TN reached up to 88.2%. It showed that the simultaneous nitrification and de-nitrification phenomenon happened in the aerobic zone. The nitrogen removal mechanism was also studied.

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Comparative Bio-sorption of Cadmium and Nickel Ions from Aqueous Solution onto Fibers of Date Palm using Fluidized Bed Column

Revista de Chimie ◽

10.37358/rc.19.5.7160 ◽

2019 ◽

Vol 70 (5) ◽

pp. 1507-1512

Author(s):

Baker M. Abod ◽

Ramy Mohamed Jebir Al-Alawy ◽

Firas Hashim Kamar ◽

Gheorghe Nechifor

Keyword(s):

Aqueous Solution ◽

Heavy Metal ◽

Metal Ions ◽

Fluidized Bed ◽

Removal Efficiency ◽

Heavy Metal Ions ◽

Date Palm ◽

Operating Conditions ◽

Initial Concentration ◽

Bed Height

The aim of this study is to use the dry fibers of date palm as low-cost biosorbent for the removal of Cd(II), and Ni(II) ions from aqueous solution by fluidized bed column. The effects of many operating conditions such as superficial velocity, static bed height, and initial concentration on the removal efficiency of metal ions were investigated. FTIR analyses clarified that hydroxyl, amine and carboxyl groups could be very effective for bio-sorption of these heavy metal ions. SEM images showed that dry fibers of date palm have a high porosity and that metal ions can be trapped and sorbed into pores. The results show that a bed height of 6 cm, velocity of 1.1Umf and initial concentration for each heavy metal ions of 50 mg/L are most feasible and give high removal efficiency. The fluidized bed reactor was modeled using ideal plug flow and this model was solved numerically by utilizing the MATLAB software for fitting the measured breakthrough results. The breakthrough curves for metal ions gave the order of bio-sorption capacity as follow: Cd(II)]Ni(II).

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Upflow packed bed Anammox reactor used in two-stage deammonification of sludge digester effluent

Water Science & Technology ◽

10.2166/wst.2018.322 ◽

2018 ◽

Vol 78 (9) ◽

pp. 1843-1851 ◽

Cited By ~ 3

Author(s):

İ. Çelen-Erdem ◽

E. S. Kurt ◽

B. Bozçelik ◽

B. Çallı

Keyword(s):

Removal Efficiency ◽

Nitrogen Removal ◽

Municipal Wastewater ◽

Removal Rate ◽

Treatment Plant ◽

Packed Bed ◽

Municipal Wastewater Treatment ◽

Two Stage ◽

N Removal ◽

Total Nitrogen Removal

Abstract The sludge digester effluent taken from a full scale municipal wastewater treatment plant (WWTP) in Istanbul, Turkey, was successfully deammonified using a laboratory scale two-stage partial nitritation (PN)/Anammox (A) process and a maximum nitrogen removal rate of 1.02 kg N/m3/d was achieved. In the PN reactor, 56.8 ± 4% of the influent NH4-N was oxidized to NO2-N and the effluent nitrate concentration was kept below 1 mg/L with 0.5–0.7 mg/L of dissolved oxygen and pH of 7.12 ± 12 at 24 ± 4°C. The effluent of the PN reactor was fed to an upflow packed bed Anammox reactor where high removal efficiency was achieved with NO2-N:NH4-N and NO3-N:NH4-N ratios of 1.32 ± 0.19:1 and 0.22 ± 0.10:1, respectively. The results show that NH4-N removal efficiency up to 98.7 ± 2.4% and total nitrogen removal of 87.7 ± 6.5% were achieved.

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Removal of organic matter and nitrogen in an horizontal subsurface flow (HSSF) constructed wetland under transient loads

Water Science & Technology ◽

10.2166/wst.2009.548 ◽

2009 ◽

Vol 60 (7) ◽

pp. 1677-1682 ◽

Cited By ~ 29

Author(s):

A. Albuquerque ◽

M. Arendacz ◽

M. Gajewska ◽

H. Obarska-Pempkowiak ◽

P. Randerson ◽

...

Keyword(s):

Organic Matter ◽

Constructed Wetland ◽

Removal Rate ◽

Subsurface Flow ◽

Point Sources ◽

Operating Conditions ◽

Mass Removal ◽

Mass Load ◽

Horizontal Subsurface Flow ◽

Transient Loads

A monitoring campaign in a horizontal subsurface flow constructed wetland under the influence of transient loads of flow-rate, organic matter, nitrogen and suspended solids showed an irregular removal of COD and TSS and lower both removal efficiencies and mass removal rates than the ones observed in other studies for similar operating conditions. This circumstance is associated to the presence of large amount of particulate organic matter from non-point sources. The mass removal rate of ammonia increased 39% as both the water and soil temperatures increased from weeks 1–8 to weeks 9–14. A good correlation between mass load and mass removal rate was observed for all measured parameters, which attests a satisfactory response of the bed under to transient loads.

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Nitrogen removal in a fluidized bed bioreactor by using mixed culture under oxygen-limited conditions

Water Science & Technology ◽

10.2166/wst.2004.0390 ◽

2004 ◽

Vol 50 (6) ◽

pp. 313-320 ◽

Cited By ~ 10

Author(s):

T. Khin ◽

A.P. Annachhatre

Keyword(s):

Fluidized Bed ◽

Mixed Culture ◽

Nitrogen Removal ◽

Removal Rate ◽

Flow Rates ◽

Fluidized Bed Bioreactor ◽

Oxygen Gas ◽

Do Concentration ◽

Total Nitrogen Removal ◽

Nitrification And Denitrification

Nitrogen removal involving nitrification and denitrification was investigated in a fluidized bed bioreactor by using mixed culture sludge under oxygen-limited conditions. Methane was used as a sole carbon source for denitrification. In this study, optimal nitrification and denitrification rates were examined by varying methane and oxygen gas dissolution flow rates, 90 ml/min, 400 ml/min and 650 ml/min, in each. Simultaneously nitrification and denitrification was achieved. The total nitrogen removal rate was 15-mg N/g VSS. d, 21-mg N/g VSS. d and 26.4-mg N/g VSS. d at gas dissolution flow rate 90 ml/min, 400 ml/min and 650 ml/min, respectively. No significant accumulation of nitrite was found in this experiment. Nitrogen removal rates depend on gas dissolution flow rates. DO concentration was at 0.5Ð2 mg/L.

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Nitrogen removal efficiency and microbial community analysis of ANAMMOX biofilter at ambient temperature

Water Science & Technology ◽

10.2166/wst.2015.019 ◽

2015 ◽

Vol 71 (5) ◽

pp. 725-733 ◽

Cited By ~ 8

Author(s):

Zeng Taotao ◽

Li Dong ◽

Zeng Huiping ◽

Xie Shuibo ◽

Qiu Wenxin ◽

...

Keyword(s):

Microbial Community ◽

Ambient Temperature ◽

Removal Efficiency ◽

Nitrogen Removal ◽

Denaturing Gradient Gel Electrophoresis ◽

Removal Rate ◽

Ammonia Concentration ◽

Visual Observation ◽

Microbial Community Analysis ◽

Anammox Bacteria

An upflow anaerobic biofilter (AF) was developed to investigate anaerobic ammonium-oxidizing (ANAMMOX) efficiency in treating low-strength wastewater at ambient temperature (15.3–23.2 °C). Denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization were used to investigate treatment effects on the microbial community. Stepwise decreases in influent ammonia concentration could help ANAMMOX bacteria selectively acclimate to low-ammonia conditions. With an influent ammonia concentration of 46.5 mg/L, the AF reactor obtained an average nitrogen removal rate of 2.26 kg/(m3 day), and a removal efficiency of 75.9%. polymerase chain reaction-DGGE results showed that microbial diversity in the low matrix was greater than in the high matrix. Microbial community structures changed when the influent ammonia concentration decreased. The genus of functional ANAMMOX bacteria was Candidatus Kuenenia stuttgartiensis, which remained stationary across study phases. Visual observation revealed that the relative proportions of ANAMMOX bacteria decreased from 41.6 to 36.3% across three study phases. The AF bioreactor successfully maintained high activity due to the ANAMMOX bacteria adaptation to low temperature and substrate conditions.

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Kinetic Modelling and Determination of Octyl Phenol Ethoxylate (OPE) and Bisphenol A (BPA) (used as plastic additives) Inhibition Constants for Nitrogen Conversion

Global NEST Journal ◽

10.30955/gnj.003591 ◽

2021 ◽

Keyword(s):

Kinetic Model ◽

Bisphenol A ◽

Nitrogen Removal ◽

Removal Rate ◽

Kinetic Modelling ◽

Ammonium Nitrogen ◽

Operating Conditions ◽

Optimum Operating ◽

Octyl Phenol ◽

Inhibition Constants

<p>Conversion of ammonia to nitrate is sensitive to a number of inhibitors. There is limited information on the nitrification inhibition coefficient and kinetic model in the current literature. Octyl Phenol Ethoxylate (OPE) and Bisphenol A (BPA) inhibition constants were found in nitrogen removal using an activated sludge system. Firstly, OPE and BPA free wastewater was used to determine the optimum operating conditions. The effect of OPE and BPA concentration on system performance was investigated. The ammonium removal rate was less affected by lower OPE and BPA concentrations. When the BPA and OPE concentrations were increased from 0 mg/L to 30 mg/L, the outlet ammonium nitrogen concentrations were increased respectively from 2.8 mg/L to 49.8 mg/L and from 2.6 mg/L to 20.40 mg/L. Due to the inhibition created by these compounds on Nitrobacter, nitrite nitrogen increased in the medium. As the OPE and BPA concentrations increased, the conversion rate of the ammonium nitrogen into nitrate decreased. Based on the experimental results, a kinetic model was developed, and the OPE and BPA inhibition constants (KOPE and KBPA) were found to be 40.7 mg/L and 11.76 mg/L, respectively. In nitrogen removal, BPA created a higher inhibition effect in comparison to OPE.</p>

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Effect of Fe on Nitrogen Removal Rate and Microbes of Anammox

E3S Web of Conferences ◽

10.1051/e3sconf/202127104006 ◽

2021 ◽

Vol 271 ◽

pp. 04006

Author(s):

Bing Wang ◽

Bing Sun ◽

Yunlong Liu ◽

Lin Yang

Keyword(s):

Removal Efficiency ◽

Nitrogen Removal ◽

Positive Impact ◽

Removal Rate ◽

Positive Effect

With the anammox sludge as the inoculation sludge, the effect of different concentrations of Fe2+ and Fe3+ on the denitrification performance of the anammox reaction was explored by setting a control experiment.The results showed that when the Fe2+ concentration was 0.08mmol/l, the reactor had the best removal efficiency, the removal rate of NH4+-N was 89.14% after 60h, and the removal rate of NO2--N was 85.9%. The positive effect of Fe3+ on the anammox reaction was similar to that of Fe2+. From reading the literature, it can be known that Fe has a positive impact on anammox microorganisms in three aspects by promoting microbial enrichment, promoting the production of functional enzymes, and promoting microbial granulation.

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Research on Biological Fluidized Bed System Treatment Performance and Nitrogen Removal Process for Seafood Processing Wastewater with Different Operation Conditions

Water ◽

10.3390/w13192630 ◽

2021 ◽

Vol 13 (19) ◽

pp. 2630

Author(s):

Yi Ding ◽

Hong You ◽

Wei Sun ◽

Zhansheng Guo ◽

Junxue Mei ◽

...

Keyword(s):

Fluidized Bed ◽

Removal Efficiency ◽

Nitrogen Removal ◽

Reduction Process ◽

Nitrite Reduction ◽

Nitrogen And Phosphorus ◽

Removal Process ◽

Operation Conditions ◽

Nitrification And Denitrification ◽

Seafood Processing

In this study, the biological fluidized bed system was used to treat seafood processing wastewater. The sludge was collected from the secondary sedimentation tank of a municipal wastewater treatment plant and acclimated for 200 days before the experiment. The treatment efficiencies of simulated seafood processing wastewater by biological fluidized bed system with different sludge concentrations, different hydraulic retention times (HRTs) and different bio-carriers were studied. The results showed that the removal efficiency of nitrogen and phosphorus increased with the increasing sludge concentration and by extending hydraulic retention time, and the higher removal efficiency of nitrogen and phosphorus could be obtained with the higher specific surface area of the bio-carrier. The nitrogen removal process analysis showed that the nitrification and denitrification activity of sludge could be changed with different operation conditions resulting in different nitrogen removal efficiency in the biological fluidized bed system. This was mainly because the change tendency of the ammonia nitrogen oxidizing process, nitrite oxidizing process, nitrite reduction process and nitrate reduction process was different with different operation conditions in a high salinity environment. Theoretically, the difference of the inhibitory effect of a high-salt environment on different nitrification and denitrification processes could be used to realize shortcut nitrification denitrification by controlling a certain operation condition.

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

Water Science & Technology ◽

10.2166/wst.2020.271 ◽

2020 ◽

Vol 81 (9) ◽

pp. 2033-2042 ◽

Cited By ~ 1

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.

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Performance and microbial community of the CANON process in a sequencing batch membrane bioreactor with elevated COD/N ratios

Water Science & Technology ◽

10.2166/wst.2020.089 ◽

2020 ◽

Vol 81 (1) ◽

pp. 138-147

Author(s):

Xiaoling Zhang ◽

Xincong Liu ◽

Meng Zhang

Keyword(s):

Organic Matter ◽

Microbial Community ◽

Nitrogen Removal ◽

Membrane Bioreactor ◽

Ammonia Oxidation ◽

Heterotrophic Bacteria ◽

Removal Rate ◽

Ammonia Oxidizing Bacteria ◽

Anaerobic Ammonia Oxidation ◽

Canon Process

Abstract In this study, the effects of elevated chemical oxygen demand/nitrogen (COD/N) ratios on nitrogen removal, production and composition of the extracellular polymer substances (EPS) and microbial community of a completely autotrophic nitrogen removal via nitrite (CANON) process were studied in a sequencing batch membrane bioreactor (SBMBR). The whole experiment was divided into two stages: the CANON stage (without organic matter in influent) and the simultaneous partial nitrification, anaerobic ammonia oxidation and denitrification (SNAD) stage (with organic matter in influent). When the inflow ammonia nitrogen was 420 mg/L and the COD/N ratio was no higher than 0.8, the addition of COD was helpful to the CANON process; the total nitrogen removal efficiency (TNE) was improved from approximately 65% to more than 75%, and the nitrogen removal rate (NRR) was improved from approximately 0.255 kgN/(m3·d) to approximately 0.278 kgN/(m3•d), while the TNE decreased to 60%, and the NRR decreased to 0.236 kgN/(m3•d) when the COD/N ratio was elevated to 1.0. For the EPS, the amounts of soluble EPS (SEPS) and loosely bound EPS (LB-EPS) were both higher in the CANON stage than in the SNAD stage, while the amount of tightly bound EPS (TB-EPS) in the SNAD stage was significantly higher due to the proliferation of heterotrophic bacteria. The metagenome sequencing technique was used to analyse the microbial community in the SBMBR. The results showed that the addition of COD altered the structure of the bacterial community in the SBMBR. The amounts of Candidatus ‘Anammoxoglobus’ of anaerobic ammonia oxidation bacteria (AAOB) and Nitrosomonas of ammonia oxidizing bacteria (AOB) both decreased significantly, and Nitrospira of nitrite oxidizing bacteria (NOB) was always in the reactor, although the amount changed slightly. A proliferation of denitrifiers related to the genera of Thauera, Dokdonella and Azospira was found in the SBMBR.

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