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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Immobilized cell augmented activated sludge process for enhanced nitrogen removal from wastewater
Rungrod Jittawattanarat1, Konstantinos Kostarelos, Eakalak Khan
1Department of Civil Engineering, Polytechnic University, Brooklyn, New York, USA.
Summary
The immobilized cell augmented activated sludge (ICAAS) system enhances nitrogen removal by 24% in wastewater treatment. This bioaugmentation method offers a viable upgrade for existing activated sludge systems.
Area of Science:
- Environmental Engineering
- Microbiology
Background:
- Activated sludge systems are crucial for wastewater treatment.
- Improving nitrogen removal efficiency is a key challenge in wastewater management.
Purpose of the Study:
- To investigate enhanced nitrogen removal using the immobilized cell augmented activated sludge (ICAAS) system.
- To evaluate the effectiveness of bioaugmentation with co-immobilized nitrifiers and denitrifiers.
Main Methods:
- Laboratory-scale batch enricher-reactors were used to cultivate nitrifying and denitrifying bacteria.
- Cellulose triacetate was employed as the immobilization medium for bacteria at a 2:1 mass ratio.
- The immobilized cells were used to augment a laboratory-scale completely mixed activated sludge system (CMAS) treating synthetic wastewater.
Main Results:
- The ICAAS system achieved 24% higher nitrogen removal compared to the control CMAS.
- The control CMAS demonstrated a nitrogen removal rate of 28% +/- 7%.
- Augmentation volumes of 5-20% by volume of co-immobilized cells significantly improved treatment performance.
Conclusions:
- The ICAAS system is a promising strategy for enhancing nitrogen removal in wastewater treatment.
- Bioaugmentation with immobilized nitrifiers and denitrifiers offers a viable method for upgrading existing activated sludge processes.
- The ICAAS approach provides a cost-effective solution for improving wastewater treatment efficiency.
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