Performance and activated sludge characteristics at short solid retention time in a submerged MBR: effects of C/N ratio of wastewater

Environ Technol. 2019 Jul;40(16):2085-2092. doi: 10.1080/09593330.2018.1437223. Epub 2018 Feb 22.

Abstract

This study investigated the effect of carbon to nitrogen (C/N) ratio of influent wastewater on performance and activated sludge properties at a sludge retention time of 5 d in a submerged membrane bioreactor. The chemical oxygen demand and ammonia-Nitrogen (NH3-N) removal efficiencies were found to be over 96.3% and 86.9% in the sMBRs having different C/N ratios. It was found that total extracellular polymeric substances and total soluble microbial products increased with an increase in C/N ratio. It was also observed that critical flux, relative hydrophobicity and zeta potential values decreased, and capillary suction time, particle size and viscosity of sludge increased as the C/N ratio increased.

Keywords: Membrane bioreactors; activated sludge; extracellular polymeric substances; physico-chemical characteristic; short solid retention time.

MeSH terms

  • Bioreactors
  • Carbon
  • Membranes, Artificial
  • Nitrogen
  • Sewage*
  • Waste Disposal, Fluid
  • Wastewater*

Substances

  • Membranes, Artificial
  • Sewage
  • Waste Water
  • Carbon
  • Nitrogen