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Updated: Aug 7, 2026
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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Optimization of nitrogen removal for alternating intermittent aeration-type activated sludge system: a new process
Guclu Insel1, Seval Sözen, Serden Başak
1Environmental Engineering Department, Istanbul Technical University, Maslak, Istanbul, Turkey. inselhay@itu.edu.tr
Summary
A modified activated sludge process with two reactors in series improves nitrogen removal stability. This enhanced configuration boosts both nitrification and denitrification, outperforming single-reactor systems.
Area of Science:
- Environmental Engineering
- Wastewater Treatment
Background:
- Intermittent aeration is crucial for nitrogen removal in wastewater treatment.
- Single-reactor systems can face limitations in achieving stable nitrification and denitrification.
Purpose of the Study:
- To propose and evaluate a novel activated sludge process modification for enhanced nitrogen removal.
- To compare the performance of a two-compartment reactor against a single-reactor system under intermittent aeration.
Main Methods:
- Utilized an activated sludge simulation model to test the proposed process.
- Implemented a two-compartment reactor configuration in series.
- Operated the system in intermittent aeration mode with dissolved oxygen set-point control.
Main Results:
- The two-compartment configuration demonstrated superior nitrogen removal performance.
- The modified system showed competitive advantages in both nitrification and denitrification capacities.
- Dissolved oxygen set-point control during aeration significantly impacted nitrogen removal efficiency.
Conclusions:
- A two-compartment activated sludge reactor in series offers a more stable and efficient approach to nitrogen removal.
- Process optimization, including dissolved oxygen control, is key for maximizing performance in intermittent aeration systems.
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