Efficient single-stage autotrophic nitrogen removal with dilute wastewater through oxygen supply control

Wonji Kwak, Perry L. McCarty, Jaeho Bae, Yu Tzu Huang, Po Heng Lee

Research output: Journal article publicationJournal articleAcademic researchpeer-review

34 Citations (Scopus)


Autotrophic nitrogen removal via ammonia oxidizing (AOB) and anaerobic ammonium oxidizing (anammox) bacteria was evaluated for treatment of a dilute 50mg/L ammonia-containing solution in a single-stage nitrogen-removal filter at 25°C. Important was an external oxygenation system that permitted close control and measurement of oxygen supply, a difficulty with the generally used diffused air systems. Hydraulic retention time (HRT) was reduced in steps from 15 to 1h. At 1h HRT, total nitrogen (TN) removals varied between 73% and 94%, the maximum being obtained with a benchmark oxygenation ratio of 0.75mol O2/mol ammonia fed. At higher ratios, nitrate was formed causing TN removal efficiency to decrease. With lower ratios, TN and ammonia removals decreased in proportion to the decrease in BOR. When operating at or below the BOR, nitrate formation equaled no more than 2% of the ammonia removed, a value much less than has previously been reported.
Original languageEnglish
Pages (from-to)400-405
Number of pages6
JournalBioresource Technology
Publication statusPublished - 1 Nov 2012


  • Anaerobic ammonium oxidation (Anammox)
  • Autotrophic nitrogen removal
  • Dilute wastewater
  • Partial nitrification
  • Precise oxygen supply

ASJC Scopus subject areas

  • Bioengineering
  • Environmental Engineering
  • Waste Management and Disposal

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