A two-sludge system for simultaneous biological C, N and P removal via the nitrite pathway

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

Journal of Environmental Science and Health Part A ◽

10.1081/ese-120023340 ◽

2003 ◽

Vol 38 (10) ◽

pp. 2125-2134 ◽

Cited By ~ 8

Author(s):

Nazik Artan ◽

Nevin Ozgur Yagci ◽

S. Reha Artan ◽

Derin Orhon

Keyword(s):

Nitrogen Removal ◽

High Strength ◽

Biological Nitrogen Removal ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Biological Nitrogen

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Biological Nitrogen Removal of High Salinity Produced Water in Sequencing Batch Reactors

Proceedings of the Water Environment Federation ◽

10.2175/193864708788735655 ◽

2008 ◽

Vol 2008 (17) ◽

pp. 128-141

Author(s):

V. Santiago ◽

R. Souza ◽

B. Versiani ◽

A. Cerqueira ◽

F. Rodrigues ◽

...

Keyword(s):

Nitrogen Removal ◽

Produced Water ◽

High Salinity ◽

Biological Nitrogen Removal ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Biological Nitrogen

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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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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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Partial Nitrification in Microaerobic Tank of “Anoxic-Anaerobic- Microaerobic-Aerobic (A2O2)” Biological Nitrogen Removal Process

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.1039 ◽

2013 ◽

Vol 295-298 ◽

pp. 1039-1044 ◽

Cited By ~ 1

Author(s):

Jian Lei Gao ◽

Bing Nan Lv ◽

Yi Xin Yan ◽

Jian Ping Wu

Keyword(s):

Nitrogen Removal ◽

Removal Rate ◽

Pilot Scale ◽

Partial Nitrification ◽

Biological Nitrogen Removal ◽

Nitrogenous Fertilizer ◽

Removal Process ◽

Batch Tests ◽

N Removal ◽

Biological Nitrogen

The pilot-scale Anoxic-Anaerobic-Microaerobic-Aerobic (A2O2) biological nitrogen removal process was used to treat the wastewater from nitrogenous fertilizer production with C/N ratio of 1~2. Batch tests were conducted to investigate the patial nitrification using the activated sludge from the microaerobic tank rich in nitrite bacteria as the experimental object. Results showed that 95% removal efficiency of NH3-N could be obtained with the HRT of 30 h. The SVI affected the NH3-N removal rate and the optimal SVI was 106 mL/g. The ORP was well correlated with the logarithm of NH3-N concentration with the linear regression equation of y=-57.233x+3.308. Moreover, the kinetic model for partial nitrification was determined as v=4.762s/(9.86+s).

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Multistage wastewater treatment using separated storage driven denitrification and nitrification biofilms

Water Science & Technology ◽

10.2166/wst.2006.170 ◽

2006 ◽

Vol 53 (6) ◽

pp. 51-58 ◽

Cited By ~ 5

Author(s):

L. J. Hughes ◽

J. Lancaster ◽

R. Cord-Ruwisch

Keyword(s):

Nitrogen Removal ◽

Filter Design ◽

Removal Rate ◽

Biological Nitrogen Removal ◽

Trickling Filter ◽

Waste Streams ◽

N Removal ◽

Beta Hydroxybutyrate ◽

Biological Nitrogen ◽

Further Development

The feasibility of combining a previously reported storage driven denitrification biofilm, where 80% of influent acetate can be converted to poly-beta-hydroxybutyrate (PHB), with a suitable nitrification reactor, either submerged or trickling filter design, to achieve complete biological nitrogen removal was tested. The reactor system showed the potential of complete biological nitrogen removal of waste streams with a C/N ratio as low as 3.93 kg COD/kg N-NH3 at an overall nitrogen removal rate of 1.1 mmole NH3/L/h. While the efficiency and the rates of nitrogen removal were higher than what is observed in traditional or simultaneous nitrification and denitrification (SND) systems, there were two problems that require further development: (a) the incomplete draining of the reactor caused ammonia retention and release in the effluent, limiting the overall N-removal and (b) pH drifts in the nitrification step slowed down the rate of nitrification if not corrected by appropriate pH adjustment or buffering.

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Biological phosphorus and nitrogen removal in sequencing batch reactors: effects of cycle length, dissolved oxygen concentration and influent particulate matter

Water Science & Technology ◽

10.2166/wst.2013.324 ◽

2013 ◽

Vol 68 (5) ◽

pp. 982-990 ◽

Cited By ~ 8

Author(s):

Maneesha P. Ginige ◽

Ahmet S. Kayaalp ◽

Ka Yu Cheng ◽

Jason Wylie ◽

Anna H. Kaksonen

Keyword(s):

Particulate Matter ◽

Dissolved Oxygen ◽

Cycle Length ◽

Batch Reactors ◽

Sequencing Batch Reactors ◽

Organic C ◽

N Removal ◽

Do Concentration ◽

Biological Phosphorus ◽

P Removal

Removal of phosphorus (P) and nitrogen (N) from municipal wastewaters is required to mitigate eutrophication of receiving water bodies. While most treatment plants achieve good N removal using influent carbon (C), the use of influent C to facilitate enhanced biological phosphorus removal (EBPR) is poorly explored. A number of operational parameters can facilitate optimum use of influent C and this study investigated the effects of cycle length, dissolved oxygen (DO) concentration during aerobic period and influent solids on biological P and N removal in sequencing batch reactors (SRBs) using municipal wastewaters. Increasing cycle length from 3 to 6 h increased P removal efficiency, which was attributed to larger portion of N being removed via nitrite pathway and more biodegradable organic C becoming available for EBPR. Further increasing cycle length from 6 to 8 h decreased P removal efficiencies as the demand for biodegradable organic C for denitrification increased as a result of complete nitrification. Decreasing DO concentration in the aerobic period from 2 to 0.8 mg L−1 increased P removal efficiency but decreased nitrification rates possibly due to oxygen limitation. Further, sedimented wastewater was proved to be a better influent stream than non-sedimented wastewater possibility due to the detrimental effect of particulate matter on biological nutrient removal.

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