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Updated: Jun 14, 2026
08:13
A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Modelling and simulation revealing mechanisms likely responsible for achieving the nitrite pathway through aeration
A Guisasola1, M Marcelino, R Lemaire
1Departament d'Enginyeria Química, Universitat Autònoma de Barcelona, 08193, Bellaterra, Catalonia, Spain. albert.guisasola@uab.cat
Summary
Nitrogen removal via nitrite offers cost savings. Competition for nitrite, not kinetics, drives nitrite-oxidizing bacteria washout, aiding efficient nitrogen removal.
Area of Science:
- Environmental microbiology
- Wastewater treatment engineering
- Biochemical process modeling
Background:
- Nitrogen removal via nitrite is increasingly favored over nitrate for reduced aeration and chemical oxygen demand (COD) costs.
- Established control strategies, including aerobic phase length and low dissolved oxygen (DO) setpoints, facilitate the nitrite pathway in sludge-retention systems.
Purpose of the Study:
- To investigate the role of microbial competition versus kinetic selection in nitrite-oxidizing bacteria (NOB) washout.
- To evaluate the impact of simultaneous nitrification and denitrification (SND) on nitrite pathway efficiency and COD utilization.
Main Methods:
- Utilizing mathematical modeling and simulation to analyze microbial dynamics.
- Examining the competition between nitrite-reducing and nitrite-oxidizing bacteria for nitrite.
Main Results:
- Competition for nitrite, not kinetic selection, is the primary factor causing NOB washout.
- Simultaneous nitrification and denitrification under aerobic conditions significantly aids nitrite pathway achievement.
- Enhanced COD utilization is observed with the occurrence of SND.
Conclusions:
- Understanding nitrite competition is crucial for optimizing nitrogen removal processes.
- SND presents a promising strategy for improving the efficiency of biological nitrogen removal.
- The nitrite pathway offers substantial economic and environmental benefits in wastewater treatment.
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