title: Towards advanced aeration modelling: from blower to bubbles to bulk.
abstract: Aeration is an essential component of aerobic biological wastewater treatment and is the largest energy consumer at most water resource recovery facilities. Most modelling studies neglect the inherent complexity of the aeration systems used. Typically, the blowers, air piping, and diffusers are not modelled in detail, completely mixed reactors in a series are used to represent plug-flow reactors, and empirical correlations are used to describe the impact of operating conditions on bubble formation and transport, and oxygen transfer from the bubbles to the bulk liquid. However, the mechanisms involved are very complex in nature and require significant research efforts. This contribution highlights why and where there is a need for more detail in the different aspects of the aeration system and compiles recent efforts to develop physical models of the entire aeration system (blower, valves, air piping and diffusers), as well as adding rigour to the oxygen transfer efficiency modelling (impact of viscosity, bubble size distribution, shear and hydrodynamics). As a result of these model extensions, more realistic predictions of dissolved oxygen profiles and energy consumption have been achieved. Finally, the current needs for further model development are highlighted.
authors.affiliation: BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, Ghent 9000, Belgium E-mail: andreia.amaral@ugent.be; MARETEC, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, Lisboa 1049-001, Portugal.
authors.forename: Andreia
authors.initials: A
authors.lastname: Amaral
authors.affiliation: inCTRL Solutions Inc., 470 Anthony Drive, Oakville, ON L6J 2K5, Canada.
authors.forename: Oliver
authors.initials: O
authors.lastname: Schraa
authors.affiliation: inCTRL Solutions Inc., 470 Anthony Drive, Oakville, ON L6J 2K5, Canada.
authors.forename: Leiv
authors.initials: L
authors.lastname: Rieger
authors.affiliation: Irstea, UR MALY, centre de Lyon-Villeurbanne, 5 rue de la Doua, Villeurbanne cedex F-69926, France.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Gillot
authors.affiliation: Irstea, UR HBAN, centre d'Antony, 1 rue Pierre-Gilles de Gennes, Antony cedex F-92761, France.
authors.forename: Yannick
authors.initials: Y
authors.lastname: Fayolle
authors.affiliation: BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, Ghent 9000, Belgium E-mail: andreia.amaral@ugent.be; Department of Civil and Environmental Engineering, University of Florence, via di S. Marta, 3, Florence 50139, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Bellandi
authors.affiliation: BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, Ghent 9000, Belgium E-mail: andreia.amaral@ugent.be.
authors.forename: Youri
authors.initials: Y
authors.lastname: Amerlinck
authors.affiliation: BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, Ghent 9000, Belgium E-mail: andreia.amaral@ugent.be.
authors.forename: Séverine T F C
authors.initials: ST
authors.lastname: Mortier
authors.affiliation: Department of Civil and Environmental Engineering, University of Florence, via di S. Marta, 3, Florence 50139, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Gori
authors.affiliation: MARETEC, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, Lisboa 1049-001, Portugal.
authors.forename: Ramiro
authors.initials: R
authors.lastname: Neves
authors.affiliation: BIOMATH, Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Coupure Links 653, Ghent 9000, Belgium E-mail: andreia.amaral@ugent.be.
authors.forename: Ingmar
authors.initials: I
authors.lastname: Nopens
mesh_terms: D004058:Diffusion; D057446:Hydrodynamics; D008962:Models, Theoretical; D010100:Oxygen / Q000032:analysis*; D014783:Viscosity; D062065:Wastewater / Q000737:chemistry; D018508:Water Purification / Q000295:instrumentation* / Q000379:methods*
chemical_list: D010100:Oxygen; D062065:Wastewater