Development of four-stage moving bed biofilm reactor train with a pre-denitrification configuration for the removal of thiocyanate and cyanate

Bioresour Technol. 2015 Apr;181:254-62. doi: 10.1016/j.biortech.2015.01.051. Epub 2015 Jan 20.

Abstract

Two trains (A and B) of four-stage moving bed biofilm reactors (MBBRs) were developed for the degradation of thiocyanate (SCN(-)), cyanate (OCN(-)) and ammonia (NH3). A pre-denitrification configuration was established in the first-stage reactor of the B train using SCN(-) and OCN(-) as the sole carbon source. SCN(-), OCN(-) and NH3 were completely removed in both trains. The highest removal of total nitrogen equivalent (total-N) occurred at a loading rate of 5.6 mg-N L(-1) h(-1). The pre-denitrification configuration resulted in increased total-N removal in the B train (62.6%) compared to the A train (38.5%). Thiobacillus spp. were the predominant bacteria in all MBBRs. Bacteria related to bioprocesses involving anaerobic ammonium oxidation were present in the B train, suggesting that part of nitrogen removal occurs via this pathway. Our results showed that the pre-denitrification configuration increases the efficiency of removal of total-N compounds in the SCN(-)/OCN(-)-degrading MBBR process.

Keywords: Cyanate; MBBR; Pre-denitrification; Thiobacillus; Thiocyanate.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Ammonia / analysis
  • Base Sequence
  • Biodegradation, Environmental
  • Biodiversity
  • Biofilms*
  • Bioreactors / microbiology*
  • Cyanates / isolation & purification*
  • Denitrification*
  • Environmental Restoration and Remediation / instrumentation*
  • Environmental Restoration and Remediation / methods*
  • Equipment Design
  • Nitrates / analysis
  • Nitrogen / analysis
  • Phylogeny
  • RNA, Ribosomal, 16S / genetics
  • Thiobacillus / metabolism
  • Thiocyanates / isolation & purification*
  • Wastewater

Substances

  • Cyanates
  • Nitrates
  • RNA, Ribosomal, 16S
  • Thiocyanates
  • Waste Water
  • Ammonia
  • Nitrogen
  • thiocyanate