Effect of COD/N ratio on cultivation of aerobic granular sludge in a pilot-scale sequencing batch reactor

Appl Microbiol Biotechnol. 2013 Feb;97(4):1745-53. doi: 10.1007/s00253-012-3991-6. Epub 2012 Apr 12.

Abstract

Aerobic granular sludge was successfully cultivated with the effluent of internal circulation reactor in a pilot-scale sequencing batch reactor (SBR). Soy protein wastewater was used as an external carbon source for altering the influent chemical oxygen demand/nitrogen (COD/N) ratios of SBR. Initially, the phenomenon of partial nitrification was observed and depressed by increasing the influent COD/N ratios from 3.32 to 7.24 mg/mg. After 90 days of aerobic granulation, the mixed liquor suspended solids concentration of the reactor increased from 2.80 to 7.02 g/L, while the sludge volumetric index decreased from 105.51 to 42.99 mL/g. The diameters of mature aerobic granules vary in the range of 1.2 to 2.0 mm. The reactor showed excellent removal performances for COD and N₄⁺--N after aerobic granulation, and average removal efficiencies were over 93% and 98%, respectively. The result of this study could provide further information on the development of aerobic granule-based system for full-scale applications.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aerobiosis
  • Bacteria / chemistry
  • Bacteria / growth & development
  • Bacteria / metabolism*
  • Biological Oxygen Demand Analysis
  • Bioreactors / microbiology*
  • Kinetics
  • Nitrogen / analysis*
  • Nitrogen / metabolism
  • Oxygen / analysis*
  • Oxygen / metabolism
  • Particle Size
  • Pilot Projects
  • Sewage / chemistry
  • Sewage / microbiology*

Substances

  • Sewage
  • Nitrogen
  • Oxygen