title: A rheological approach to analyze aerobic granular sludge.
abstract: Aerobic granular sludge is one promising biotechnology in wastewater treatment. Despite intensive researches on granular architecture and strategies to improve treatment efficiency, there are still some elusive material parameters needed to stimulate the granulation process. The main aim of this study was to evaluate aerobic granular sludge innovatively using the universal rheology methodology, in terms of processability or quality and texture. Steady shear and oscillatory measurements were performed. Basic rheological characterization showed that aerobic granular sludge was a shear-thinning Herschel-Bulkley fluid with yield pseudoplasticity. Meanwhile, granular sludge presented characterized viscoelastic behaviors in dynamic sweeps highlighting its superiority to flocculent sludge. Furthermore, a Wagner-type constitutive model incorporating a relaxation and damping function was introduced and able to describe the time-dependent and non-linear viscoelastic behaviors. This study could make a further step on predicting rheological properties, helping improve the actual sludge treatment process and the operation of sludge dewatering.
authors.affiliation: Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Yun-Jie
authors.initials: YJ
authors.lastname: Ma
authors.affiliation: Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Cheng-Wang
authors.initials: CW
authors.lastname: Xia
authors.affiliation: Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
authors.forename: Hai-Yang
authors.initials: HY
authors.lastname: Yang
authors.affiliation: Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China. Electronic address: rzeng@ustc.edu.cn.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Zeng
mesh_terms: D000332:Aerobiosis; D055119:Elastic Modulus; D008962:Models, Theoretical; D012212:Rheology / Q000379:methods*; D012722:Sewage / Q000737:chemistry*; D013696:Temperature; D014783:Viscosity; D014867:Water / Q000737:chemistry
chemical_list: D012722:Sewage; D014867:Water
keywords: In-situ rheological characterization; Non-linear viscoelasticity; Steady shear flow; Viscoelastic properties; Wagner-type model