Preliminary assessment of a shortcut in nitrogen removal from wastewater

1986 ◽  
Vol 13 (6) ◽  
pp. 600-605 ◽  
Author(s):  
O. Turk ◽  
D. S. Mavinic
Keyword(s):  
Nitrogen Removal ◽  
Oxygen Demand ◽  
Ammonia Concentration ◽  
Free Ammonia ◽  
Nitrite Reduction ◽  
Nitrification Rate ◽  
Nitrite Accumulation ◽  
Nitrite Level ◽  
In Series ◽  
System 2

The objective of this long-term research project was to demonstrate the feasibility of removing nitrogen from highly nitrogenous wastewater by (a) blocking the nitrification process at the intermediary nitrite level through the action of free ammonia and (b) subsequently reducing the nitrite to nitrogen gas. The success of such a process could lead to substantial reductions in nitrogen removal costs.Two identical bench-scale activated sludge systems were operated for 147 days, in the initial phase. Each system was composed of four equal-sized, completely mixed cells in series. The free ammonia concentration was highest in the first cell of each system. It averaged 2 mg NH3-N/L in the first system and 5 mg NH3-N/L in the second. Nitrite buildup, in excess of 80% of the oxidized nitrogen present, was induced and sustained for around 2 months in all cells of the second system, after which time a steady decline occurred. Nitrite buildup could not be sustained in the first system. Average chemical oxygen demand (COD) for nitrite reduction was 40% lower than that for nitrate reduction. The nitrification rate for the ammonia oxidizers was similar for both systems. The presence of up to 100 mg [Formula: see text] nitrite in system 2 caused no discernible inhibition. Subsequent runs proved that nitrite accumulation could not be sustained indefinitely, owing to acclimation to free ammonia levels as high as 22 mg NH3-N/L. Periodic resting and flushing may be required; further research is being pursued along these lines. Key words: biological treatment, denitrification, nitrification, nitrite, nitrogen removal, nitrogenous wastewater.

Modelling of biological nitrogen removal during treatment of piggery wastewater

2007 ◽  
Vol 55 (10) ◽  
pp. 11-19 ◽  
Author(s):  
F. Béline ◽  
H. Boursier ◽  
F. Guiziou ◽  
E. Paul
Keyword(s):  
Experimental Data ◽  
Maximum Growth ◽  
Ammonia Concentration ◽  
Pilot Scale ◽  
Free Ammonia ◽  
Effect Of Temperature ◽  
Nitrification Rate ◽  
Nitrite Accumulation ◽  
Piggery Wastewater ◽  
Pilot Scale Reactor

During this study, a mathematical model simulating piggery wastewater treatment was developed, with the objective of process optimisation. To achieve this, the effect of temperature and free ammonia concentration on the nitrification rate were experimentally studied using respirometry. The maximum growth rates obtained were higher for ammonium-oxidising biomass than for nitrite-oxidising biomass for the temperatures above 20 °C; values at 35 °C were equal to 1.9 and 1.35 day−1, respectively. No inhibition of nitrification was observed for free ammonia concentrations up to 50 mgN/L. Using these data with others experimental data obtained from a pilot-scale reactor to treat piggery wastewater, a model based on a modified version of the ASM1 was developed and calibrated. In order to model the nitrite accumulation observed, the ASM1 model was extended with a two-step nitrification and denitrification including nitrite as intermediate. Finally, the produced model called PiWaT1 demonstrated a good fit with the experimental data. In addition to the temperature, oxygen concentration was identified as an important factor influencing the nitrite accumulation during nitrification. Even if some improvements of the model are still necessary, this model can already be used for process improvement.

Nitrogen removal characteristics of nitrification and denitrification filters

1994 ◽  
Vol 29 (10-11) ◽  
pp. 409-416 ◽  
Author(s):  
F. Çeçen ◽  
I. E. Gönenç
Keyword(s):  
Nitrogen Removal ◽  
Rate Constants ◽  
Order Rate Constant ◽  
Zero Order ◽  
Ammonia Removal ◽  
Nitrite Accumulation ◽  
Order Kinetic ◽  
Order Rate ◽  
In Series ◽  
Nitrification And Denitrification

The kinetics of nitrogen removal was studied in upflow submerged nitrification and denitrification filters in series. Nitrification followed first-, half-, and zero-order kinetics. For the half-order range the half-order rate constant was about 0.9gNH4-N1/2m−1/2d−1. The zero-order rate constants for the DO ranges of 2-3 mg/L and 4-5 mg/L were found as 0.47 gNH4-Nm−2d−1 and 1.82 gNH4-Nm−2d−1, respectively. In the zero-order region ammonia removal proceeded as a half-order reaction in oxygen concentration and the half-order rate constants were about 1.4-2.7 gO21/2m−1/2d−1. Nitrite accumulation reached a considerable degree at bulk oxygen to bulk ammonia ratios lower than 5 since the formation of nitrate was inhibited. Similar to nitrification half- and zero-order kinetic regions were also observed in denitrification. The half- and zero-order rate constants for carbon unlimited cases (influent COD/NOx-N>5) were about 0.23 gNOx-N1/2m−1/2d−1 and 1.9 gNOx-Nm−2d−1, respectively. The nitrite produced in the nitrification stage could be reduced in denitrification. The removal kinetics in the presence of nitrite was found to be similar to the kinetics when the influent consisted of nitrate only.

Exploration of rapid start-up of the CANON process from activated sludge inoculum in a sequencing biofilm batch reactor (SBBR)

2015 ◽  
Vol 73 (3) ◽  
pp. 535-542 ◽  
Author(s):  
Yangfan Deng ◽  
Xiaoling Zhang ◽  
Ying Miao ◽  
Bo Hu
Keyword(s):  
Nitrogen Removal ◽  
Dna Analysis ◽  
Removal Rate ◽  
Batch Reactor ◽  
Ammonia Concentration ◽  
Nitrite Accumulation ◽  
Start Up ◽  
Fast Start ◽  
Total Nitrogen Removal ◽  
Canon Process

In this study, a laboratory-scale sequencing biofilm batch reactor (SBBR) was employed to explore a fast start-up of completely autotrophic nitrogen removal over nitrite (CANON) process. Partial nitrification was achieved by controlling free ammonia concentration and operating at above 30 °C; then the reactor was immediately operated with alternating periods of aerobiosis and anaerobiosis to start the anammox process. The CANON process was successfully achieved in less than 50 d, and the total-nitrogen removal efficiency and the nitrogen removal rate were 81% and 0.14 kg-N m−3 d−1 respectively. Afterwards, with the increasing of ammonium loading rate a maximum nitrogen removal rate of 0.39 kg-N m−3 d−1 was achieved on day 94. DNA analysis showed that ‘Candidatus Brocadia’ was the dominant anammox species and Nitrosomonas was the dominant aerobic ammonium-oxidizing bacteria in the CANON reactor. This study revealed that due to shortening the persistent and stable nitrite accumulation period the long start-up time of the CANON process can be significantly reduced.

Effects of different hydraulic models on predicting longitudinal profiles of reactive pollutants in activated sludge reactors

2008 ◽  
Vol 58 (3) ◽  
pp. 555-561 ◽  
Author(s):  
P. Zima ◽  
J. Makinia ◽  
M. Swinarski ◽  
K. Czerwionka
Keyword(s):  
Activated Sludge ◽  
Ammonia Concentration ◽  
Minor Role ◽  
Nitrification Rate ◽  
Concentration Profiles ◽  
One Dimensional ◽  
Advection Dispersion ◽  
In Series ◽  
The One ◽  
A Minor

This paper presents effects of dispersion on predicting longitudinal ammonia concentration profiles in activated sludge bioreactor located at “Wschod” WWTP in Gdansk. The aim of this study was to use the one-dimensional advection-dispersion Equation (ADE) to simulate the flow conditions (based on the inert tracer concentrations in selected points) and longitudinal profile of reactive pollutant (based on the ammonia concentration profiles in selected points). The simulation results were compared with the predictions obtained using a traditional “tanks-in-series” (TIS) approach, commonly used in designing biological reactors. The use of dispersion coefficient calculated from an empirical formula resulted in substantial differences in the tracer concentration distributions in two sampling points in the bioreactor. Simulations using the one-dimensional ADE and TIS model, with the nitrification rate incorporated as the source term, revealed that the hydraulic model plays a minor role compared to the biochemical transformations in predicting the longitudinal ammonia concentration profiles.

Nitrite accumulation in submerged biofilters - combined effects

1996 ◽  
Vol 34 (3-4) ◽  
pp. 371-378 ◽  
Author(s):  
F. Fdz-Polanco ◽  
S. Villaverde ◽  
P. A. Garcia
Keyword(s):  
Ammonia Concentration ◽  
Relative Activity ◽  
Free Ammonia ◽  
Effect Of Temperature ◽  
Ammonia Oxidizer ◽  
Ammonium Concentration ◽  
Nitrite Accumulation ◽  
Biological Aerated Filter ◽  
Ammonia Inhibition ◽  
Aerated Filter

The combined effect of temperature, pH and ammonium concentration over the nitrite accumulation phenomena in situations of free ammonia inhibition, their effect over the ammonia and nitrite oxidizer microorganiisms influence over the nitrification, have been studied in an Up-flow Biological Aerated Filter (UBAF). The free ammonia inhibition effect highly depends on the values of pH, temperature and ammonium concentration. For the same specific free ammonia concentration different values of temperature, pH and ammonium concentration bring about different nitrite accumulations. In conditions of no free ammonia inhibition and low values of temperature and pH, high ammonium concentrations bring about a higher relative activity of ammonia oxidizer microorganisms of the filter increases the nitratation efficiency in zones close to the outlet and will favour the nitrite accumulation in situations of free ammonia inhibition.

Simultaneous carbon and nitrogen removal using a litre-scale upflow microbial fuel cell

2013 ◽  
Vol 69 (2) ◽  
pp. 293-297 ◽  
Author(s):  
Ling-ling Zhao ◽  
Tian-shun Song
Keyword(s):  
Fuel Cell ◽  
Microbial Fuel Cell ◽  
Nitrogen Removal ◽  
Microbial Fuel Cells ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Chicken Manure ◽  
Synthetic Wastewater ◽  
Nitrification Rate ◽  
Carbon And Nitrogen

A 10 L upflow microbial fuel cell (UMFC) was constructed for simultaneous carbon and nitrogen removal. During the 6-month operation, the UMFC constantly removed carbon and nitrogen, and then generated electricity with synthetic wastewater as substrate. At 5.0 mg L−1 dissolved oxygen, 100 Ω external resistance, and pH 6.5, the maximum power density (Pmax) and nitrification rate for the UMFC was 19.5 mW m−2 and 17.9 mg·(L d)−1, respectively. In addition, Pmax in the UMFC with chicken manure wastewater as substrate was 16 mW m−2, and a high chemical oxygen demand (COD) removal efficiency of 94.1% in the UMFC was achieved at 50 mM phosphate-buffered saline. Almost all ammonia in the cathode effluent was effectively degraded after biological denitrification in the UMFC cathode. The results can help to further develop pilot-scale microbial fuel cells for simultaneous carbon and nitrogen removal.

scholarly journals Nitrogen Removal Efficiency for Pharmaceutical Wastewater with a Single-Stage Anaerobic Ammonium Oxidation Process

2020 ◽  
Vol 17 (21) ◽  
pp. 7972
Author(s):  
Lushen Zuo ◽  
Hong Yao ◽  
Huayu Li ◽  
Liru Fan ◽  
Fangxu Jia
Keyword(s):  
Nitrogen Removal ◽  
Oxygen Demand ◽  
Single Stage ◽  
Anaerobic Ammonium Oxidation ◽  
Ammonium Concentration ◽  
Nitrite Accumulation ◽  
Ammonia Oxidizing Bacteria ◽  
Ammonium Oxidation ◽  
Pharmaceutical Wastewater ◽  
High Concentrations

A single-stage anaerobic ammonium oxidation (ANAMMOX) process with an integrated biofilm–activated sludge system was carried out in a laboratory-scale flow-through reactor (volume = 57.6 L) to treat pharmaceutical wastewater containing chlortetracycline. Partial nitrification was successfully achieved after 48 days of treatment with a nitrite accumulation of 70%. The activity of ammonia oxidizing bacteria (AOB) decreased when the chemical oxygen demand (COD) concentration of the influent was 3000 mg/L. When switching to the single-stage ANAMMOX operation, (T = 32–34 °C, DO = 0.4–0.8 mg/L, pH = 8.0–8.5), the total nitrogen (TN) removal loading rate and efficiency were 1.0 kg/m3/d and 75.2%, respectively, when the ammonium concentration of the influent was 287 ± 146 mg/L for 73 days. The findings of this study imply that single-stage ANAMMOX can achieve high nitrogen removal rates and effectively treat pharmaceutical wastewater with high concentrations of COD (1000 mg/L) and ammonium.

Sustainable nitrogen removal by denitrifying anammox applied for anaerobic pre-treated potato wastewater

2012 ◽  
Vol 66 (12) ◽  
pp. 2630-2637 ◽  
Author(s):  
A. Mulder ◽  
A. I. Versprille ◽  
D. van Braak
Keyword(s):  
Nitrogen Removal ◽  
Oxygen Demand ◽  
Nitrogen Loading ◽  
Biofilm Reactor ◽  
Ammonium Oxidation ◽  
Loading Rates ◽  
Removal Capacity ◽  
Nitrite Production ◽  
Conversion Rates ◽  
In Series

The feasibility of sustainable nitrogen removal was investigated in a two stage biofilm configuration consisting of a MBBR (Moving Bed Biofilm Reactor) and a Deamox reactor (Biobed-EGSB). The MBBR is used for nitrification and the denitrifying ammonium oxidation (Deamox) is aimed at a nitrogen removal process in which part of the required nitrite for the typical anammox reaction originated from nitrate. Anaerobic pre-treated potato wastewater was supplied to a MBBR and Deamox reactor operated in series with a bypass flow of 30%. The MBBR showed stable nitrite production at ammonium-loading rates of 0.9–1.0 kg NH4-N/m3 d with ammonium conversion rates of 0.80–0.85 kg NH4-N/m3 d. The nitrogen-loading rate and conversion rate of the Deamox reactor were 1.6–1.8 and 1.6 kg N/m3 d. The maximum ammonium removal capacity in the Deamox reactor was 0.6 kg NH4-N/m3 d. The removal efficiency of soluble total nitrogen reached 90%. The Deamox process performance was found to be negatively affected during decline of the operating temperature from 33 to 22 °C and by organic loading rates with a chemical oxygen demand (COD)/NO2-N ratio >1.

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