The forward osmosis membrane bioreactor: A low fouling alternative to MBR processes

Andrea Achilli, Tzahi Y. Cath, Eric A. Marchand, Amy E. Childress

Research output: Contribution to journalArticlepeer-review

672 Scopus citations


A novel osmotic membrane bioreactor (OsMBR) is presented. The system utilizes a submerged forward osmosis (FO) membrane module inside a bioreactor. Through osmosis, water is transported from the mixed liquor across a semi-permeable membrane, and into a draw solution (DS) with a higher osmotic pressure. To produce potable water, the diluted DS is treated in a reverse osmosis (RO) unit; the by-product is a reconcentrated DS for reuse in the FO process. Preliminary results from experiments conducted with a flat-sheet cellulose triacetate FO membrane demonstrated high sustainable flux and relatively low reverse transport of solutes from the DS into the mixed liquor. Membrane fouling was controlled with osmotic backwashing. The FO membrane was found to reject 98% of organic carbon and 90% of ammonium-nitrogen; the OsMBR process (bioreactor and FO membrane) was found to remove greater than 99% of organic carbon and 98% of ammonium-nitrogen, respectively; suggesting a better compatibility of the OsMBR with downstream RO systems than conventional membrane bioreactors.

Original languageEnglish (US)
Pages (from-to)10-21
Number of pages12
Issue number1-3
StatePublished - Apr 2009
Externally publishedYes


  • Forward osmosis
  • Membrane bioreactor
  • Membrane fouling
  • Nutrient removal
  • Wastewater treatment

ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Materials Science(all)
  • Water Science and Technology
  • Mechanical Engineering


Dive into the research topics of 'The forward osmosis membrane bioreactor: A low fouling alternative to MBR processes'. Together they form a unique fingerprint.

Cite this