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Updated: Jul 10, 2026
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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Multi-scale individual-based model of microbial and bioconversion dynamics in aerobic granular sludge
Joao B Xavier1, Merle K De Kreuk, Cristian Picioreanu
1Biomathematics group, Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, R. Qta Grande 6, 2780 Oeiras, Portugal. jxavier@cgr.harvard.edu
Environmental Science & Technology
|October 24, 2007
Summary
Aerobic granular sludge sequencing batch reactors (GSBR) offer integrated wastewater treatment. A multiscale model reveals that nitrogen removal primarily occurs through alternating nitrification/denitrification, optimizing this promising technology.
Area of Science:
- Environmental Microbiology
- Biochemical Engineering
- Wastewater Treatment Technologies
Background:
- Aerobic granular sludge (AGS) is an innovative biological wastewater treatment method.
- It efficiently removes chemical oxygen demand (COD), nitrogen, and phosphate.
- Sequencing batch reactors (SBRs) are commonly used in wastewater treatment.
Purpose of the Study:
- To develop a multiscale model for aerobic granular sludge sequencing batch reactors (GSBR).
- To describe the complex population dynamics and nutrient removal within GSBRs.
- To investigate the influence of operating conditions on microbial populations and activity.
Main Methods:
- A multiscale model was developed, encompassing macro (bulk concentrations) and micro (granule scale) levels.
- Individual-based modeling (IbM) was used to simulate the spatial arrangement of four bacterial groups within a granule.
- Kinetic models were employed for phosphate accumulating organisms (PAO), including storage compounds like PHA, polyphosphate, and glycogen.
Main Results:
- The model successfully simulated short-term solute dynamics, comparable to experimental data.
- Long-term simulations demonstrated the dependence of microbial population and activity on operating conditions.
- Nitrogen removal in GSBR was found to occur predominantly via alternating nitrification/denitrification.
Conclusions:
- The multiscale model provides insights into GSBR operation and microbial behavior.
- Alternating nitrification/denitrification is a key strategy for enhancing nitrogen removal in GSBRs.
- This study supports GSBR as a promising technology for advanced wastewater treatment.
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