title: Nitrite accumulation during denitrification depends on the carbon quality and quantity in wastewater treatment with biofilters.
abstract: This study aims to understand the mechanisms of nitrite appearance during wastewater denitrification by biofilters, focusing on the role of the carbon source. Experiments were carried out at lab-scale (batch tests) and full-scale plant (Parisian plant, capacities of 240,000 m(3) day(-1)). Results showed that the nature of the carbon source affects nitrite accumulation rates. This accumulation is low, 0.05 to 0.10 g N-NO2(-) per g N-NO3(-) eliminated, for alcohols such as methanol, ethanol, or glycerol. The utilization of glycerol leads to fungal development causing clogging of the biofilters. This fungal growth and consequent clogging exclude this carbon source, with little nitrite accumulation, as carbon source for denitrification. Whatever the carbon source, the C/N ratio in the biofilter plays a major role in the appearance of residual nitrite; an optimal C/N ratio from 3.0 to 3.2 allows a complete denitrification without any nitrite accumulation.
authors.affiliation: SIAAP-Direction du Développement et de la Prospective, 82 avenue Kléber, 92700, Colombes, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Rocher
authors.forename: Anniet M
authors.initials: AM
authors.lastname: Laverman
authors.forename: Johnny
authors.initials: J
authors.lastname: Gasperi
authors.forename: Sam
authors.initials: S
authors.lastname: Azimi
authors.forename: Sabrina
authors.initials: S
authors.lastname: Guérin
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mottelet
authors.forename: Thierry
authors.initials: T
authors.lastname: Villières
authors.forename: André
authors.initials: A
authors.lastname: Pauss
mesh_terms: D058440:Denitrification; D005374:Filtration; D005990:Glycerol / Q000737:chemistry; D009566:Nitrates / Q000032:analysis / Q000737:chemistry; D009573:Nitrites / Q000032:analysis* / Q000737:chemistry; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification
chemical_list: D005990:Glycerol; D009566:Nitrates; D009573:Nitrites; D062065:Wastewater; D014874:Water Pollutants, Chemical