title: Long-term performance and microbial community characterization of an osmotic anammox system for removing reverse-fluxed ammonium.
abstract: A novel osmotic anammox (OsAMX) system coupling nitritation-anammox with forward osmosis (FO) has been developed for removal of reverse-fluxed ammonium when using NH4HCO3 as a draw solute. In this study, long-term performance and microbial community structure were investigated. The nitritation-anammox reactor maintained an ammonium concentration of 7.0±5.0mgNL(-1) (DO=0.9±0.2mgO2L(-1)), while the FO achieved a water flux of 2.3±0.4LMH (0.5M NH4HCO3 draw). The low water flux was obtained likely due to concentration polarization, reverse salt flux (RSF) and membrane fouling. Sequencing analyses reveled that Candidatus Jettenia was the dominant anammox genus, while Candidatus Brocadia was most abundant in biofilm. The shift of anammox bacterial population indicated possible higher tolerance of Ca. Brocadia for DO or elevated RSF. These results encourage further investigation of OsAMX system optimization, membrane fouling migration strategies, and application with actual wastewater.
authors.affiliation: Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: Xiaojin
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Crop and Soil Environmental Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: Shan
authors.initials: S
authors.lastname: Sun
authors.affiliation: Department of Crop and Soil Environmental Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Badgley
authors.affiliation: Department of Civil and Environmental Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA. Electronic address: zhenhe@vt.edu.
authors.forename: Zhen
authors.initials: Z
authors.lastname: He
mesh_terms: D064751:Ammonium Compounds / Q000737:chemistry* / Q000378:metabolism*; D001419:Bacteria; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology*; D059013:Microbial Consortia; D009995:Osmosis; D062065:Wastewater / Q000737:chemistry
chemical_list: D064751:Ammonium Compounds; D062065:Wastewater
keywords: Forward osmosis; Membrane fouling; Microbial community; Nitritation–anammox; Reverse salt flux