title: A unified theory for upscaling aerobic granular sludge sequencing batch reactors.
abstract: Aerobic granular sludge sequencing batch reactors (SBR) are a promising technology for treating wastewater. Increasing evidence suggests that aerobic granulation in SBRs is driven by selection pressures exerted on microorganisms. Three major selection pressures have been identified as follows: settling time, volume exchange ratio and discharge time. This review demonstrates that these three major selection pressures can all be unified to one, the minimal settling velocity of bio-particles, that determines aerobic granulation in SBRs. The unified selection pressure theory is a useful guide for manipulating and optimizing the formation and characteristics of aerobic granules in SBRs. Furthermore, the unified theory provides a single engineering basis for scale up of aerobic granular sludge SBRs.
authors.affiliation: Division of Environmental and Water Resources Engineering, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore. cyliu@ntu.edu.sg
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhi-Wu
authors.initials: ZW
authors.lastname: Wang
authors.forename: Joo-Hwa
authors.initials: JH
authors.lastname: Tay
mesh_terms: D001420:Bacteria, Aerobic / Q000166:cytology / Q000502:physiology*; D019149:Bioreactors / Q000382:microbiology*; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods; D049109:Cell Proliferation; D003198:Computer Simulation; D019544:Equipment Failure Analysis / Q000379:methods*; D007218:Industrial Microbiology / Q000295:instrumentation / Q000379:methods; D008954:Models, Biological; D010316:Particle Size; D010865:Pilot Projects; D012722:Sewage / Q000382:microbiology*
chemical_list: D012722:Sewage