• Auto-aggregation: Adhesion between the cells of genetically identical strains.
• Co-aggregation: Aggregation between genetically different bacterial strains.
6.2.5 Other Mechanisms
Role of dominating microbial species (Barr et al. 2010) and addition of crushed
granules inside a sequencing batch reactor (Verawaty et al. 2012) are the other
probable granulation mechanisms reported so far.
In another literature, different steps of aerobic granulation are described by Hailei
et al. (2006) which are illustrated in Fig. 6.3.
6.3 Characteristics of Aerobic Granules
Characteristics of aerobic granules are determined by physical, chemical and biological parameters.
1 mm
1 mm
1 mm
1 mm
1 mm
1 mm
(a)
(b)
(c)
(d)
(e)
(f)
Fig. 6.3 Micrograms of granulation phenomena are illustrated. Picture depicting (a) initial sludge;
(b) multiplication of sludge bacteria; (c) appearance of bacterial floc; (d) cohesion of the floc; (e)
maturation of floc; (f) formation of aerobic granule (Hailei et al. 2006)
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