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Updated: Apr 11, 2026
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The Benthic Exchange of O2, N2 and Dissolved Nutrients Using Small Core Incubations
Published on: August 3, 2016
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[Effect of oxygen on partial nitrification in a membrane bioreactor]
Summary
Optimal partial nitrification in a membrane bioreactor (MBR) requires careful control of dissolved oxygen (DO). A DO concentration of 0.5 mg/L is ideal for feeding an Anammox system, with low DO and high aeration rates enhancing efficiency.
Area of Science:
- Environmental Science
- Biotechnology
- Wastewater Treatment
Background:
- Partial nitrification is a key step in wastewater treatment for nitrogen removal.
- Membrane bioreactors (MBRs) offer advantages for biological wastewater treatment processes.
- Optimizing dissolved oxygen (DO) is crucial for efficient partial nitrification.
Purpose of the Study:
- To determine critical dissolved oxygen (DO) concentrations for optimal partial nitrification in an MBR.
- To investigate the relationship between DO, oxygen uptake rate (OUR), and oxygen supply rate (OSR).
- To identify suitable conditions for partial nitrification effluent to feed an Anammox system.
Main Methods:
- Utilized a membrane bioreactor (MBR) to study partial nitrification.
- Monitored dissolved oxygen (DO) concentrations, oxygen uptake rate (OUR), and oxygen supply rate (OSR).
- Analyzed effluent nitrite and ammonia ratios at various DO levels.
Main Results:
- Nitrite accumulation was observed at a DO concentration of 1 mg/L.
- An effluent nitrite to ammonia ratio near 1 was achieved at 0.5 mg/L DO, suitable for Anammox systems.
- At 20 g/L mixed liquid suspended solids (MLSS), OUR and OSR indicated oxygen supply limitations.
Conclusions:
- Dissolved oxygen concentration significantly impacts partial nitrification efficiency in MBRs.
- A low DO concentration (0.5 mg/L) is optimal for producing effluent suitable for Anammox systems.
- Implementing a control strategy of low DO and high aeration rates can improve partial nitrification efficiency.
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