title: Effect of extended famine conditions on aerobic granular sludge stability in the treatment of brewery wastewater.
abstract: Results obtained from three aerobic granular sludge reactors treating brewery wastewater are presented. Reactors were operated for 60d days in each of the two periods under different cycle duration: (Period I) short 6h cycle, and (Period II) long 12h cycle. Organic loading rates (OLR) varying from 0.7kgCODm-3d-1to 4.1kgCODm-3d-1were tested. During Period I, granules successfully developed in all reactors, however, results revealed that the feast and famine periods were not balanced and the granular structure deteriorated and became irregular. During Period II at decreased 12h cycle time, granules were observed to develop again with superior structural stability compared to the short 6h cycle time, suggesting that a longer starvation phase enhanced production of proteinaceous EPS. Overall, the extended famine conditions encouraged granule stability, likely because long starvation period favours bacteria capable of storage of energy compounds.
authors.affiliation: Department of Civil, Environmental, Aerospatial Engineering and Material, University of Palermo, Viale delle Scienze, Building 8, 90128 Palermo, Italy. Electronic address: santofabio.corsino@unipa.it.
authors.forename: Santo Fabio
authors.initials: SF
authors.lastname: Corsino
authors.affiliation: Department of Civil Engineering, University of Manitoba, Winnipeg R3T 5V6, Canada.
authors.forename: Alessandro
authors.initials: A
authors.lastname: di Biase
authors.affiliation: Department of Civil Engineering, University of Manitoba, Winnipeg R3T 5V6, Canada.
authors.forename: Tanner Ryan
authors.initials: TR
authors.lastname: Devlin
authors.affiliation: Department of Civil and Environmental Engineering, University of Florence, Via S. Marta 3, 50139 Florence, Italy.
authors.forename: Giulio
authors.initials: G
authors.lastname: Munz
authors.affiliation: Department of Civil, Environmental, Aerospatial Engineering and Material, University of Palermo, Viale delle Scienze, Building 8, 90128 Palermo, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Torregrossa
authors.affiliation: Department of Civil Engineering, University of Manitoba, Winnipeg R3T 5V6, Canada.
authors.forename: Jan A
authors.initials: JA
authors.lastname: Oleszkiewicz
mesh_terms: D000332:Aerobiosis; D001419:Bacteria / Q000378:metabolism; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology; D002244:Carbon / Q000378:metabolism; D019649:Food Industry; D012722:Sewage / Q000737:chemistry / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D062065:Wastewater / Q000737:chemistry
chemical_list: D002244:Carbon; D012722:Sewage; D062065:Wastewater
keywords: Aerobic granular sludge; Extracellular polymeric substances; Feast/famine; Industrial wastewater; Stability