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Updated: Jan 25, 2026
07:59
Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors
Published on: December 6, 2018
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Simultaneous nitrification, denitrification and phosphorus removal in a sequencing batch reactor (SBR) under low
Can Li1, Shufeng Liu1, Tao Ma1
1Department of Environmental Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China.
Chemosphere
|May 12, 2019
Summary
Achieving simultaneous nitrogen and phosphorus removal in cold wastewater is challenging. This study demonstrates high removal efficiencies at 10°C using a sequencing batch reactor, highlighting the role of denitrifying polyphosphate accumulating organisms (PAOs).
Area of Science:
- Environmental Science
- Microbiology
- Water Treatment Engineering
Background:
- Simultaneous nitrogen and phosphorus removal in wastewater is difficult during winter due to low microbial activity.
- Effective nutrient removal is crucial for preventing eutrophication and protecting water bodies.
Purpose of the Study:
- To investigate the feasibility and mechanisms of simultaneous nitrification, denitrification, and phosphorus removal (SNDPR) at low temperatures.
- To identify key microbial communities responsible for high nutrient removal efficiency in cold conditions.
Main Methods:
- Laboratory-scale sequencing batch reactor (SBR) operation at 10°C.
- Analysis of total nitrogen (TN) and total phosphorus (TP) removal efficiencies.
- Fluorescence in situ hybridization (FISH) and 16S rRNA amplicon sequencing for microbial community analysis.
- Assessment of nitrous oxide (N2O) emissions.
Main Results:
- High TN (89.6%) and TP (97.5%) removal efficiencies were achieved at 10°C and a COD/N ratio of 6.
- N2O emission was 7.46% of TN, with nitrifier denitrification contributing significantly (70%).
- Polyphosphate accumulating organisms (PAOs), particularly denitrifying PAOs utilizing nitrite (PAOII), dominated the microbial community.
- The genus Propionivibrio (48.9%) was identified as a key player in low-temperature nutrient removal.
Conclusions:
- The SNDPR process is highly effective at low temperatures, driven by denitrifying PAOs and nitrifier denitrification.
- Denitrifying PAOs, especially PAOII, are crucial for simultaneous nitrogen and phosphorus removal in cold wastewater.
- Propionivibrio enrichment suggests its significant role in cold-adapted biological nutrient removal systems.
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