title: A new device to select carriers for biomass immobilization and application in an aerobic/anaerobic fixed-bed sequencing batch biofilm reactor for nitrogen removal.
abstract: This study proposes a new approach to selecting a biofilm carrier for immobilization using dissolved oxygen (DO) microsensors to measure the thickness of aerobic and anaerobic layers in biofilm. The biofilm carriers tested were polyurethane foam, mineral coal (MC), basaltic gravel, and low-density polyethylene. Development of layers in the biofilm carrier surface was evaluated using a flow cell device, and DO profiles were conducted to determine the size of the layers (aerobic and anaerobic). MC was the biofilm carrier selected due to allowing the development of larger aerobic and anaerobic layers in the biofilm (896 and 1,058 μm, respectively). This ability is supposed to improve simultaneous nitrogen removal by nitrification and denitrification biological processes. Thus, as a biofilm carrier, MC was used in a fixed-bed sequencing batch biofilm reactor (FB-SBBR) for treatment of wastewater with a high ammonia concentration (100-400 mgNH4+-N L-1). The FB-SBBR (15.0 L) was filled with matrices of the carrier and operated under alternating aeration and non-aeration periods of 6 h each. At a mean nitrogen loading rate of 0.55 ± 0.10 kgNH4+-N m-3d-1, the reactor attained a mean nitrification efficiency of 95 ± 9% with nitrite as the main product (aerobic period). Mean denitrification efficiency during the anoxic period was 72 ± 13%.
authors.affiliation: Department of Biochemistry and Chemical Technology, Institute of Chemistry, UNESP - Universidade Estadual Paulista, Campus Araraquara, Rua Prof. Francisco Degni 55, Araraquara, SP 14800-900, Brazil E-mail: arnaldosarti@iq.unesp.br.
authors.forename: A
authors.initials: A
authors.lastname: Sarti
authors.affiliation: Department of Hydraulics and Sanitation, University of São Paulo, (USP) - São Carlos School of Engineering, Avenida Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil.
authors.forename: A W
authors.initials: AW
authors.lastname: Lamon
authors.affiliation: Ministério do Esporte, Esplanada dos Ministérios, Bloco A, Brasília, DF 70054-906, Brazil.
authors.forename: A
authors.initials: A
authors.lastname: Ono
authors.affiliation: Department of Hydraulics and Sanitation, University of São Paulo, (USP) - São Carlos School of Engineering, Avenida Trabalhador São-carlense, 400, São Carlos, SP 13566-590, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Foresti
mesh_terms: D000641:Ammonia / Q000378:metabolism; D018441:Biofilms; D018533:Biomass; D019149:Bioreactors; D003031:Coal; D058440:Denitrification; D058465:Nitrification; D009573:Nitrites / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism*; D010100:Oxygen; D020959:Polyethylene; D011140:Polyurethanes; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D003031:Coal; D009573:Nitrites; D011140:Polyurethanes; D014874:Water Pollutants, Chemical; D000641:Ammonia; D020959:Polyethylene; C028279:polyurethane foam; D009584:Nitrogen; D010100:Oxygen