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Updated: Jul 10, 2026
06:10
Extraction of Structural Extracellular Polymeric Substances from Aerobic Granular Sludge
Published on: September 26, 2016
Settling behaviour of aerobic granular sludge
A Nor Anuar1, Z Ujang, M C M van Loosdrecht
1Institute of Environmental and Water Resource Management, Teknologi Malaysia, 81310 Johor, Malaysia. aznah_noranuar@yahoo.com
Summary
Aerobic granular sludge (AGS) settles rapidly in wastewater treatment, outperforming conventional sludge flocs. Mechanical mixing and reactor design showed minimal impact on AGS settling velocity.
Area of Science:
- Environmental Science
- Biotechnology
- Wastewater Treatment Engineering
Background:
- Aerobic granular sludge (AGS) technology is gaining attention for enhancing activated sludge systems.
- AGS offers improved sludge settling and behavior due to its compact, robust structure.
- Key advantages include fast settling and high biomass retention capacity.
Purpose of the Study:
- To compare the settling profile of AGS against other sludge flocs.
- To investigate the influence of mechanical mixing on AGS settleability.
- To assess the impact of reactor design on AGS settling.
Main Methods:
- Experimental observation of AGS settling behaviors.
- Comparative analysis of settling times for AGS and conventional sludge flocs.
- Evaluation of mechanical mixing and reactor shear effects on settling velocity.
Main Results:
- AGS demonstrated rapid settling, reaching 0.4 m depth in under 5 minutes.
- Conventional sludge flocs required over 30 minutes to settle the same depth.
- Turbulence from mixing mechanisms and reactor shear had an insignificant effect on AGS settling velocity.
Conclusions:
- AGS exhibits significantly superior settling characteristics compared to conventional sludge flocs.
- Wastewater treatment systems can benefit from AGS's fast settling and biomass retention.
- Reactor operational parameters like mixing intensity have a limited effect on AGS settling performance.
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