Anaerobic fluidized bed digestion of primary and thickened waste activated sludges

Z. Wang, M. Kim, G. Nakhla, J. Zhu

Research output: Journal PublicationArticlepeer-review

14 Citations (Scopus)


Two lab-scale anaerobic fluidized bed bioreactors (AnFBRs) treating primary sludge (PS) and thickened waste activated sludge (TWAS) were studied to explore biofilm microbial characterization. COD and VSS removal for PS showed 62% and 63%, respectively at an organic loading rate (OLR) of 18kgCODm-3d-1 and an hydraulic retention times (HRTs) of 2.2days. Similarly, TWAS was treated at 56% COD removal and 50% VSS reduction efficiencies at an OLR of 12kgCODm-3d-1 and an HRT of 4days. Furthermore, the specific bacterial community activity tests showed a significant difference between solids retention times (SRT) based on general VSS and retention times based on the activity of methanogenic, acidogenic, and acetogenic microbes. While SRT based on VSS measurements in the PS-AnFBR were 3.3days, the activity-based retention times varied from 12.5 to 16.6days. Similarly, in the TWAS-AnFBR, the SRT based on VSS measurements were 5.0days, and the activity-based retention times ranged from 9.3 to 10.8days. The BioWin model simulation predicted that conventional anaerobic digestion processes achieved lower VSS reduction efficiencies than the AnFBR process at the same SRT.

Original languageEnglish
Pages (from-to)620-629
Number of pages10
JournalChemical Engineering Journal
Publication statusPublished - 15 Jan 2016
Externally publishedYes


  • Anaerobic digestion
  • Biofilm attachment
  • Biofilm detachment
  • Fluidized bed bioreactor
  • Solids retention time
  • Specific microbial activity test

ASJC Scopus subject areas

  • Chemistry (all)
  • Environmental Chemistry
  • Chemical Engineering (all)
  • Industrial and Manufacturing Engineering


Dive into the research topics of 'Anaerobic fluidized bed digestion of primary and thickened waste activated sludges'. Together they form a unique fingerprint.

Cite this