Design of Sequencing Batch Reactors for Biological Nitrogen Removal from High Strength Wastewaters

Nitrogen removal via the nitrite pathway results in significant savings in both aeration costs and COD requirements for denitrification when compared to the conventional biological nitrogen removal process. Implementation of the nitrite pathway for simultaneous C/N/P removal in a single sludge system has a major drawback: the aeration phase disfavours denitrifying phosphorus removal. A possible configuration to overcome this issue is the utilisation of a two-sludge system where autotrophic and heterotrophic populations are physically separated. This paper experimentally demonstrates the feasibility of a nitrite-based two-sludge system with sequencing batch reactors (SBR) for the treatment of urban wastewater: a heterotrophic SBR with denitrifying PAOs for P removal and an aerobic SBR for N removal. Partial nitrification was attained in the autotrophic SBR so that shortcut biological nitrogen removal was achieved by using the anoxic dephosphatation activity of DPAOs. Finally, the effect of operating this system without pH control was studied using different influent pH values (pH = 6.8, 7.5 and 8.2) and, despite some efficiency lost due to the pH fluctuations, the system was able to remove most of the C, N and P present in the wastewater.

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Characteristics of Biological Nitrogen Removal in a Multiple Anoxic and Aerobic Biological Nutrient Removal Process

BioMed Research International ◽

10.1155/2015/531015 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Huoqing Wang ◽

Yuntao Guan ◽

Li Li ◽

Guangxue Wu

Keyword(s):

Organic Carbon ◽

Nitrogen Removal ◽

Operating Mode ◽

Biological Nutrient Removal ◽

Biological Nitrogen Removal ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Term Operation ◽

Nitrite Oxidizing Bacteria ◽

Biological Nitrogen

Two sequencing batch reactors, one with the conventional anoxic and aerobic (AO) process and the other with the multiple AO process, were operated to examine characteristics of biological nitrogen removal, especially of the multiple AO process. The long-term operation showed that the total nitrogen removal percentage of the multiple AO reactor was 38.7% higher than that of the AO reactor. In the multiple AO reactor, at the initial SBR cycle stage, due to the occurrence of simultaneous nitrification and denitrification, no nitrite and/or nitrate were accumulated. In the multiple AO reactor, activities of nitrite oxidizing bacteria were inhibited due to the multiple AO operating mode applied, resulting in the partial nitrification. Denitrifiers in the multiple AO reactor mainly utilized internal organic carbon for denitrification, and their activities were lower than those of denitrifiers in the AO reactor utilizing external organic carbon.

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Strategies to enhance the biological nitrogen removal of high-strength ammonium and low C/N landfill leachate with the SBR process

Environmental Technology ◽

10.1080/09593330.2011.586057 ◽

2012 ◽

Vol 33 (5) ◽

pp. 579-588 ◽

Cited By ~ 8

Author(s):

Y. Wang ◽

M. Pelkonen ◽

J. Kaila

Keyword(s):

Nitrogen Removal ◽

Landfill Leachate ◽

High Strength ◽

Biological Nitrogen Removal ◽

Biological Nitrogen

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Experimental validation of a simulation and design model for nitrogen removal in sequencing batch reactors

Water Science & Technology ◽

10.2166/wst.1997.0026 ◽

1997 ◽

Vol 35 (1) ◽

pp. 113-120 ◽

Cited By ~ 14

Author(s):

G. Andreottola ◽

G. Bortone ◽

A. Tilche

Keyword(s):

Nitrogen Removal ◽

Phase Distribution ◽

Nitrogen Concentration ◽

Design Procedure ◽

Aerobic Condition ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Daily Cycle ◽

Piggery Wastewater ◽

Biological Nitrogen

The development and the sensitivity analysis of a dynamic SBR simulation model for biological nitrogen removal, based on the Activated Sludge Model N. 1, are presented. An experimental study for the calibration and validation of the model was carried out using a bench scale SBR. Piggery wastewater was used as feed. The operating daily cycle of the SBR reactor included three sub-cycles of 7.5 hours each, each one alternating anoxic and aerobic condition, while settling phase was carried out at the end of the three sub-cycles. A first enhancement of model N. 1 was performed splitting nitrification into the two sub-processes of nitriation and nitratation. A second enhancement of the model was obtained with the introduction of a switch function of nitratation kinetics. An algorithm for optimization of the cycle length and phase distribution in order to minimize effluent nitrogen concentration was developed. A design procedure of SBR systems is also described.

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Optimized biological nitrogen removal of high-strength ammonium wastewater by activated sludge modeling

Journal of Water Reuse and Desalination ◽

10.2166/wrd.2017.200 ◽

2017 ◽

Vol 8 (3) ◽

pp. 393-403 ◽

Cited By ~ 3

Author(s):

Abdelsalam Elawwad

Keyword(s):

Activated Sludge ◽

Nitrogen Removal ◽

Treatment Plant ◽

High Strength ◽

Simulation Software ◽

Operating Conditions ◽

Biological Nitrogen Removal ◽

Sampling Campaign ◽

Activated Sludge Modeling ◽

Biological Nitrogen

Abstract Wastewater containing high ammonium concentrations is produced from various industrial activities. In this study, the author used a complex activated sludge model, improved by utilizing BioWin© (EnviroSim, Hamilton, Canada) simulation software, to gain understanding of the problem of instability in biological nitrogen removal (BNR). Specifically, the study focused on BNR in an industrial wastewater treatment plant that receives high-strength ammonium wastewater. Using the data obtained from a nine-day sampling campaign and routinely measured data, the model was successfully calibrated and validated, with modifications to the sensitive stoichiometric and kinetic parameters. Subsequently, the calibrated model was employed to study various operating conditions in order to optimize the BNR. These operating conditions include alkalinity addition, sludge retention time, and the COD/N ratio. The addition of a stripping step and modifications to the configuration of the aerators are suggested by the author to increase the COD/N ratio and therefore enhance denitrification. It was found that the calibrated model could successfully represent and optimize the treatment of the high-strength ammonium wastewater.

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