title: Rapid start-up and improvement of granulation in SBR.
abstract: BACKGROUND
  The aim of this study is to accelerate and improve aerobic granulation within a Sequencing Batch Reactor (SBR) by cationic polymer addition.
  
  
  METHODS
  To identify whether the polymer additive is capable of enhancing granule formation, two SBRs (R1 and R2, each 0.15 m in diameter and 2 m in height) are used by feeding synthetic wastewater. The cationic polymer with concentration of 30 to 2 ppm is added to R2, while no cationic polymer is added to R1.
  
  
  RESULTS
  Results show that the cationic polymer addition causes faster granule formation and consequently shorter reactor start-up period. The polymer-amended reactor contains higher concentration of biomass with better settling ability (23% reduction in SVI15) and larger and denser granules (112% increase of granular diameter). In addition, the results demonstrate that the cationic polymer improve the sludge granulation process by 31% increase in Extracellular Polymer Substance(EPS) concentration, 7% increase in Specific Oxygen Uptake Rate(SOUR), 18% increase in hydrophobicity, and 17% reduction in effluent Mixed Liquor Suspended Solid(MLSS) concentration.
  
  
  CONCLUSIONS
  Concludingly, it is found that using the cationic polymer to an aerobic granular system has the potential to enhance the sludge granulation process.
authors.affiliation: Department of Chemical and of Petroleum Engineering, Sharif University of Technology, Tehran, Iran.
authors.forename: Sajjad
authors.initials: S
authors.lastname: Jalali
authors.affiliation: Department of Chemical and of Petroleum Engineering, Sharif University of Technology, Tehran, Iran.
authors.forename: Jalal
authors.initials: J
authors.lastname: Shayegan
authors.affiliation: Department of Chemical and of Petroleum Engineering, Sharif University of Technology, Tehran, Iran.
authors.forename: Samira
authors.initials: S
authors.lastname: Rezasoltani
keywords: Aerobic granulation; Cationic polymer; Rapid granulation