Treatment of ferrous-NTA-based NO x scrubber solution by an up-flow anaerobic packed bed bioreactor

Appl Microbiol Biotechnol. 2015 Jun;99(12):5281-93. doi: 10.1007/s00253-014-6372-5. Epub 2015 Jan 27.

Abstract

A bench scale system consisting of an up-flow packed bed bioreactor (UAPBR) made of polyurethane foam was used for the treatment and regeneration of aqueous solution of ferrous-NTA scrubbed with nitric oxide (NO). The biomass in the UAPBR was sequentially acclimatized under denitrifying and iron reducing conditions using ethanol as electron donor, after which nitric oxide (NO) gas was loaded continuously to the system by absorption. The system was investigated for different parameters viz. pH, removal efficiency of nitric oxide, biological reduction efficiency of Fe(II)NTA-NO and COD utilization. The Fe(II)NTA-NO reduction efficiency reached 87.8 % at a loading rate of 0.24 mmol L(-1) h(-1), while the scrubber efficiency reached more than 75 % with 250 ppm NO. Stover-Kincannon and a Plug-flow kinetic model based on Michaelis-Menten equation were used to describe the UAPBR performance with respect to Fe(II)NTA-NO and COD removal. The Stover-Kincannon model was found capable of describing the Fe(II)NTA-NO reduction (R m = 8.92 mM h(-1) and K NO = 11.46 mM h(-1)) while plug-flow model provided better fit to the COD utilization (U m = 66.62 mg L(-1) h(-1), K COD = 7.28 mg L(-1)). Analyses for pH, Fe(III)NTA, ammonium, nitrite concentration, and FTIR analysis of the medium samples indicated degradation of NTA, which leads to ammonium and nitrite accumulation in the medium, and affect the regeneration process.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anaerobiosis
  • Bacteria / metabolism*
  • Biodegradation, Environmental
  • Bioreactors / microbiology*
  • Environmental Restoration and Remediation / instrumentation
  • Environmental Restoration and Remediation / methods*
  • Ferrous Compounds / chemistry
  • Ferrous Compounds / metabolism*
  • Kinetics
  • Nitric Oxide / chemistry
  • Nitric Oxide / metabolism*
  • Nitrilotriacetic Acid / chemistry
  • Nitrilotriacetic Acid / metabolism*

Substances

  • Ferrous Compounds
  • Nitric Oxide
  • Nitrilotriacetic Acid