Long-term impact of sulfate on an autotrophic nitrogen removal system integrated partial nitrification, anammox and endogenous denitrification (PAED)

Chemosphere. 2019 Nov:235:336-343. doi: 10.1016/j.chemosphere.2019.06.175. Epub 2019 Jun 24.

Abstract

A nitrogen removal system integrating partial nitrification, anaerobic ammonium oxidation (Anammox) and endogenous denitrification (PAED) was established in a sequencing batch reactor (SBR) for treating low nitrogen sewage (approximately 40 mg L-1 ammonia-nitrogen). The impact of sulfate on PAED sludge was investigated in five identical SBRs, fed with different levels of sulfate (0, 50, 100, 200 and 400 mg L-1). Ammonia oxidation was improved by the addition of Results showed that the sulfate addition in low concentration of sulfate (≤50 mg L-1), but was profoundly suppressed by higher levels of sulfate. Sulfate feeding enhanced both total nitrogen removal by Anammox and endogenous denitrification, with the abundance of Candidatus Kuenenia increasing to 4.39% in 400 mg L-1 sulfate from 0.83% in the control reactor, and Denitratisoma increasing to 6.35% from 2.77%. The results proved the feasibility of the PAED system in treating low nitrogen sewage with sulfate, which also enhanced the nitrogen-sulfate interaction.

Keywords: Anammox; Endogenous denitrification; Nitrogen removal; Partial nitrification; Sulfate; Sulfate-reducing ammonia oxidation (SRAO).

MeSH terms

  • Ammonia / chemistry*
  • Autotrophic Processes*
  • Bioreactors
  • Denitrification / drug effects*
  • Nitrification / drug effects*
  • Nitrogen
  • Oxidation-Reduction
  • Sewage / chemistry
  • Sulfates / pharmacology*

Substances

  • Sewage
  • Sulfates
  • Ammonia
  • Nitrogen