Effect of phosphorus load on nutrients removal and N2O emission during low-oxygen simultaneous nitrification and denitrification process

A sequencing batch airlift reactor was used to investigate the characteristics of nitrous oxide (N2O) emission and the succession of an ammonia-oxidizing bacteria (AOB) community. The bioreactor could successfully switch from the complete simultaneous nitrification and denitrification (SND) process to the short-cut SND process by increasing the influent pH from 7.0–7.3 to 8.0–8.3. The results obtained showed that, compared with the complete SND process, the TN removal rate and SND efficiency were improved in the short-cut SND process by approximately 13 and 11%, respectively, while the amount of N2O emission was nearly three times larger than that in the complete SND process. The N2O emission was closely associated to nitrite accumulation. Analysis of the AOB microbial community showed that nitrifier denitrification by Nitrosomonas-like AOB could be an important pathway for the enhancement of N2O emission in the short-cut SND process.

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Nitrous oxide emission in low-oxygen simultaneous nitrification and denitrification process: Sources and mechanisms

Bioresource Technology ◽

10.1016/j.biortech.2013.02.117 ◽

2013 ◽

Vol 136 ◽

pp. 444-451 ◽

Cited By ~ 58

Author(s):

Wenlin Jia ◽

Shuang Liang ◽

Jian Zhang ◽

Huu Hao Ngo ◽

Wenshan Guo ◽

...

Keyword(s):

Nitrous Oxide ◽

Nitrous Oxide Emission ◽

Simultaneous Nitrification And Denitrification ◽

Low Oxygen ◽

Nitrification And Denitrification ◽

Denitrification Process

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Simultaneous Nitrification and Denitrification in an SBR with a Modified Cycle During Reject Water Treatment

Archives of Environmental Protection ◽

10.2478/aep-2013-0008 ◽

2013 ◽

Vol 39 (1) ◽

pp. 83-91 ◽

Cited By ~ 3

Author(s):

Katarzyna Bernat

Keyword(s):

Batch Reactor ◽

Anaerobic Sludge ◽

Simultaneous Nitrification And Denitrification ◽

Low Oxygen ◽

Total Removal ◽

Operational Conditions ◽

Reject Water ◽

Do Concentration ◽

Nitrification And Denitrification ◽

Low Oxygen Concentration

Abstract In this study, the dependence between volumetric exchange rate (n) in an SBR (Sequencing Batch Reactor) with a modified cycle and simultaneous nitrification and denitrification (SND) efficiency during the treatment of anaerobic sludge digester supernatant was determined. In the SBR cycle alternating three aeration phases (with limited dissolved oxygen (DO) concentration up to 0.7 mg O2/L) and two mixing phases were applied. The lengths of each aeration and mixing phases were 4 and 5.5 h, respectively. Independently of n, a total removal of ammonium was achieved. However, at n = 0.1 d-1 and n = 0.3 d-1 nitrates were the main product of nitrification, while at n = 0.5 d-1, both nitrates and nitrites occurred in the effluent. Under these operational conditions, despite low COD/N (ca. 4) ratio in the influent, denitrification in activated sludge was observed. A higher denitrification efficiency at n = 0.5 d-1 (51.3%) than at n = 0.1 d-1 (7.8%) indicated that n was a crucial factor influencing SND via nitrite and nitrate in the SBR with a low oxygen concentration in aeration phases.

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Simultaneous nitrification and denitrification in biofilters with real time aeration control

Water Science & Technology ◽

10.2166/wst.2001.0057 ◽

2001 ◽

Vol 43 (1) ◽

pp. 269-276 ◽

Cited By ~ 51

Author(s):

N. Puznava ◽

M. Payraudeau ◽

D. Thornberg

Keyword(s):

Real Time ◽

Nitrogen Removal ◽

Simultaneous Nitrification And Denitrification ◽

Biological Aerated Filter ◽

Diffusion Effect ◽

Different Depths ◽

Nitrification And Denitrification ◽

Aerated Filter ◽

Denitrification Process ◽

Aeration Control

The aim of this article is to present a new biological aerated filter (BAF) for nitrogen removal based on simultaneous nitrification and denitrification. Contrary to the systems which integrate both an aerated and a non-aerated zone to allow complete nitrogen removal in one compact or two different units (pre-denitrification and nitrification), this upflow BAF system is based on the principle of simultaneous nitrification and denitrification since the filter is completely aerated. The denitrification process is possible due to the diffusion effect which dominates biofilm processes. The real time aeration control allows us to maintain a low dissolved oxygen value (0.5 to 3 mg O2/l). In this case, the biofilm will not be fully (or less) penetrated with oxygen and denitrification will be carried out in a large part of the biofilm. Therefore, nitrification and denitrification is running simultaneously in different depths of the biofilm. By using 50% less air this BAF gave the same results (less than 20mg TN/l) on pilot plant as a classical nitrification and denitrification BAF (Toettrup et al., 1994). Less recirculation was necessary to achieve the same denitrification.

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