title: Autotrophic nitrogen removal at low temperature.
abstract: In this work the autotrophic nitrogen removal was carried out at moderately low temperatures using two configurations: a) two-units one comprising a SHARON reactor coupled to an Anammox SBR and b) single-unit one consisting of a granular SBR performing the CANON process. At 20°C the two-units system was limited by the Anammox step and its nitrogen removal capacity was around ten times lower than the CANON system (0.08 g N/(L d) versus 1 g N/(L d)). When the CANON system was operated at 15°C the average removed nitrogen loading rate decreased to 0.2 g N/(L d). The CANON system was operated in order to limit the ammonia oxidation rate to avoid nitrite inhibition of Anammox bacteria. Since both, temperature and dissolved oxygen (DO) concentration regulate ammonia oxidizing bacteria activity, once the temperature of the reactor is decreased the DO concentration must be decreased to avoid the deeper oxygen penetration inside the granule which could cause inhibition of Anammox bacteria by oxygen and/or nitrite.
authors: Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, Rua Lope Gómez de Marzoa s/n, E-15782, Santiago de Compostela, Spain. jose.vazquez.padin@usc.es
authors: J R
authors: JR
authors: Vázquez-Padín
authors: I
authors: I
authors: Fernández
authors: N
authors: N
authors: Morales
authors: J L
authors: JL
authors: Campos
authors: A
authors: A
authors: Mosquera-Corral
authors: R
authors: R
authors: Méndez
mesh_terms: D019149:Bioreactors; D003080:Cold Temperature; D009584:Nitrogen / Q000737:chemistry / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D014874:Water Pollutants, Chemical; D009584:Nitrogen