Related Experiment Video
Updated: May 14, 2026

Estimating Sediment Denitrification Rates Using Cores and N2O Microsensors
Published on: December 6, 2018
Nitrous oxide generation in denitrifying phosphorus removal process: main causes and control measures
Cong Li1, Jian Zhang, Shuang Liang
1Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Jinan, 250100, Shandong, China.
The denitrifying phosphorus removal process generates nitrous oxide (N2O), a greenhouse gas. Continuous nitrate addition and propionate as a carbon source significantly reduce N2O emissions, improving this wastewater treatment method.
Area of Science:
- Environmental Science
- Environmental Engineering
- Water Treatment
Background:
- Denitrifying phosphorus removal (DPR) is beneficial for wastewater treatment.
- However, DPR processes generate significant amounts of nitrous oxide (N2O), a potent greenhouse gas.
- Controlling N2O emissions is crucial for the sustainability of DPR.
Purpose of the Study:
- To investigate the primary causes of N2O generation in DPR.
- To propose effective control measures for mitigating N2O emissions.
- To evaluate the efficiency of proposed control strategies.
Main Methods:
- Batch experiments were conducted to analyze N2O production and reduction rates.
- Investigated factors influencing N2O generation, including electron competition and nitrite accumulation.
- Implemented control measures: continuous nitrate addition and propionate as a carbon source.
Main Results:
- N2O generation in DPR accounted for 0.41% of total nitrogen removal, unlike conventional denitrification.
- Weak N2O reductase activity and high nitrite accumulation were identified as key causes of N2O generation.
- Continuous nitrate addition reduced N2O by 91.4%; propionate reduced N2O by 69.8%.
Conclusions:
- Weak electron competition for N2O reductase and nitrite accumulation drive N2O production in DPR.
- Continuous nitrate addition and propionate utilization are effective strategies for N2O mitigation in DPR.
- These findings offer practical solutions for reducing greenhouse gas emissions from wastewater treatment.
More Related Videos
Related Concept Videos
2° Amines to N-Nitrosamines: Reaction with NaNO2
Bioreactor Controls-I
Metabolism of Chemolithotrophs
1° Amines to Diazonium or Aryldiazonium Salts: Diazotization with NaNO2 Overview
The nitrous acid is unstable. Hence, it is formed in situ from a solution of sodium nitrite and cold aqueous acids such as hydrochloric or sulfuric acid. In an acidic solution, the –OH group of nitrous acid undergoes protonation to give oxonium ion, followed by water loss...
Bioreactor Controls-II
Overview of Nitrogen Metabolism
The largest pool of nitrogen available in the terrestrial ecosystem is gaseous nitrogen (N2) from the air, but this nitrogen...

