title: Development of four-stage moving bed biofilm reactor train with a pre-denitrification configuration for the removal of thiocyanate and cyanate.
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.
authors: Institut national de la recherche scientifique (INRS)-Institut Armand-Frappier, Laval, Québec H7V 1B7, Canada. Electronic address: richard.villemur@iaf.inrs.ca.
authors: Richard
authors: R
authors: Villemur
authors: Department of Water and Environment, CEGEP St-Laurent, Montréal, Québec H4L 3X7, Canada; Centre des technologies de l'eau, Montréal, Québec H4L 3Y2, Canada.
authors: Pierre
authors: P
authors: Juteau
authors: Institut national de la recherche scientifique (INRS)-Institut Armand-Frappier, Laval, Québec H7V 1B7, Canada.
authors: Veronique
authors: V
authors: Bougie
authors: Institut national de la recherche scientifique (INRS)-Institut Armand-Frappier, Laval, Québec H7V 1B7, Canada.
authors: Julie
authors: J
authors: Ménard
authors: Institut national de la recherche scientifique (INRS)-Institut Armand-Frappier, Laval, Québec H7V 1B7, Canada.
authors: Eric
authors: E
authors: Déziel
mesh_terms: D000641:Ammonia / Q000032:analysis; D001483:Base Sequence; D001673:Biodegradation, Environmental; D044822:Biodiversity; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology*; D003485:Cyanates / Q000302:isolation & purification*; D058440:Denitrification; D052918:Environmental Restoration and Remediation / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D009566:Nitrates / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013855:Thiobacillus / Q000378:metabolism; D013861:Thiocyanates / Q000302:isolation & purification*; D062065:Wastewater
chemical_list: D000641:Ammonia; D003485:Cyanates; D009566:Nitrates; D009584:Nitrogen; D012336:RNA, Ribosomal, 16S; D013861:Thiocyanates; D062065:Wastewater; C031760:thiocyanate
keywords: Cyanate; MBBR; Pre-denitrification; Thiobacillus; Thiocyanate