title: Study of aerobic granular sludge stability in a continuous-flow membrane bioreactor.
abstract: A granular continuous-flow membrane bioreactor with a novel hydrodynamic configuration was developed to evaluate the stability of aerobic granular sludge (AGS). Under continuous-flow operation (Period I), AGS rapidly lost their structural integrity resulting in loose and fluffy microbial aggregates in which filamentous bacteria were dominant. The intermittent feeding (Period II) allowed obtaining the succession of feast and famine conditions that favored the increase in AGS stability. Although no further breakage occurred, the formation of new granules was very limited, owing to the absence of the hydraulic selection pressure. These results noted the necessity to ensure, on the one hand the succession of feast/famine conditions, and on the other, the hydraulic selection pressure that allows flocculent sludge washout. This preliminary study shows that the proposed configuration could meet the first aspect; in contrast, biomass selection needs to be improved.
authors.affiliation: Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128 Palermo, Italy.
authors.forename: S F
authors.initials: SF
authors.lastname: Corsino
authors.affiliation: Facoltà di Ingegneria e Architettura, Università degli Studi di Enna "Kore", Cittadella Universitaria, 94100 Enna, Italy.
authors.forename: R
authors.initials: R
authors.lastname: Campo
authors.affiliation: Facoltà di Ingegneria e Architettura, Università degli Studi di Enna "Kore", Cittadella Universitaria, 94100 Enna, Italy. Electronic address: Gaetano.dibella@unikore.it.
authors.forename: G
authors.initials: G
authors.lastname: Di Bella
authors.affiliation: Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128 Palermo, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Torregrossa
authors.affiliation: Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128 Palermo, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Viviani
mesh_terms: D000332:Aerobiosis; D001419:Bacteria / Q000378:metabolism; D018533:Biomass; D019149:Bioreactors / Q000382:microbiology*; D004867:Equipment Design; D005427:Flocculation; D059013:Microbial Consortia / Q000502:physiology; D011312:Pressure; D012722:Sewage / Q000382:microbiology*; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods
chemical_list: D012722:Sewage
keywords: Aerobic granular sludge (AGS); Continuous-flow reactor; Feast/famine conditions; Hydraulic selection pressure; Membrane