Enhanced long-term ammonium removal and its ranked contribution of microbial genes associated with nitrogen cycling in a lab-scale multimedia biofilter

Bioresour Technol. 2015 Nov:196:57-64. doi: 10.1016/j.biortech.2015.07.055. Epub 2015 Jul 22.

Abstract

The multimedia biofilter achieved high and stable removal efficiencies for chemical oxygen demand (COD, 62-98%) and NH4(+) (68-98%) without costly aeration. Results revealed that lower CL (less than 13.9gCOD/m(3)d) and ACL (less than 2.8gNH4(+)-N/m(3)d) or a C/N ratio exceeding five was required to reduce NO3(-)-N accumulation and NO/N2O emission. Integrated analyses indicated that the coupling of simultaneous nitrification, anammox and denitrification processes (SNAD) were the primary reason accounted for the enhanced NH4(+)-N treatment performance. NH4(+)-N removal pathways can be ranked as follows: nitrification (amoA, archaeal) (54.6%)>partial denitrification (nirS, nirK) and anammox (37.8%)>anammox and partial denitrification (narG, napA) (12.6%). Specifically, NH4(+)-N removal was significantly inhibited by NO2(-)-N accumulation in the system (-21.6% inhibition). Results from stepwise regression analysis suggested that the NH4(+) removal rate was collectively controlled by amoA, archaeal, anammox, nirS, nirK, narG and napA.

Keywords: Biofilter; Functional gene; Nitrogen transformation; Path analysis; Quantitative relationship.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ammonia / metabolism
  • Ammonium Compounds / isolation & purification*
  • Anaerobiosis
  • Archaea / genetics
  • Archaea / metabolism
  • Bacteria / genetics
  • Bacteria / metabolism
  • Biodegradation, Environmental
  • Biological Oxygen Demand Analysis
  • Biotransformation
  • Denitrification
  • Filtration / instrumentation*
  • Genes, Microbial*
  • Laboratories*
  • Nitrification
  • Nitrogen / metabolism*
  • Nitrogen Cycle / genetics*

Substances

  • Ammonium Compounds
  • Ammonia
  • Nitrogen