Alternating anoxic feast/aerobic famine condition for improving granular sludge formation in sequencing batch airlift reactor at reduced aeration rate

Biofilms: Microbial Cities of Scientific Significance

“…The flexible component of the bacterial biofilms is the extra polymeric matrix that protects the embedded microbial cells from the external factors. The bacterial cells within the biofilms are separated by interstitial channels which allow the flow of nutrients to all the cells and in contribute the structural dimensions of the microbial biofilms [132][133][134]. Biofilms consists of major classes of macromolecules that are essential for their metabolic activities and provide the constancy.…”

Exopolysaccharides of the Biofilm Matrix: A Complex Biophysical World

“…Biofilms are also observed at interfaces as pellicles, or in the bulk of aquatic environments as flocs or granules [1,2]. A biofilm is a complex structure made of aggregates of microbial cells within a matrix of extracellular polymeric substances (EPS) (Figure 1).…”

Stability and performance of two GSBR operated in alternating anoxic/aerobic or anaerobic/aerobic conditions for nutrient removal

“…A first explanation is that COD was fully removed by denitrification, thus ensuring the absence of COD in the aerobic phase (unlike in R2). Moreover, as shown by Wan et al [18], the anoxic growth of heterotrophic bacteria in the inner layers could encourage aggregate densification. Both these situations are likely to enhance the strengthening of the granule structure and improve granule stability.…”

“…[17] or that anoxic growth inside the granule improves aggregate density [18,19]. Another reason is that alternating non-aerated feast periods and aerated famine periods encourages the selection of slow-growing bacteria, which are supposed to be positive for the densification of bio-aggregates [9].…”

“…Another reason is that alternating non-aerated feast periods and aerated famine periods encourages the selection of slow-growing bacteria, which are supposed to be positive for the densification of bio-aggregates [9]. The work of Wan et al [18] showed that the alternating anoxic feast and aerobic famine regimes allowed the formation of stable aerobic granules and simultaneous nitrification denitrification (SND) at a reduced air flow rate (SAV = 0.6 cm s −1 ). On the other hand, the alternation of anaerobic and aerobic conditions has been widely reported to promote internal biopolymer storage and enhance biological phosphorus removal by polyphosphate-accumulating organisms [20,21].…”