title: Biomethane production in an AnSBBR treating wastewater from biohydrogen process.
abstract: An anaerobic sequencing batch reactor containing immobilized biomass (AnSBBR) was used to produce biomethane by treating the effluent from another AnSBBR used to produce biohydrogen from glucose- (AR-EPHG) and sucrose-based (AR-EPHS) wastewater. In addition, biomethane was also produced from sucrose-based synthetic wastewater (AR-S) in a single AnSBBR to compare the performance of biomethane production in two steps (acidogenic and methanogenic) in relation to a one-step operation. The system was operated at 30 °C and at a fixed stirring rate of 300 rpm. For AR-EPHS treatment, concentrations were 1,000, 2,000, 3,000, and 4,000 mg chemical oxygen demand (COD) L(-1) and cycle lengths were 6 and 8 h. The applied volumetric organic loads were 2.15, 4.74, 5.44, and 8.22 g COD L(-1) day(-1). For AR-EPHG treatment, concentration of 4,000 mg COD L(-1) and 4-h cycle length (7.21 g COD L(-1) day(-1)) were used. For AR-S treatment, concentration was 4,000 mg COD L(-1) day(-1) and cycle lengths were 8 (7.04 g COD L(-1) day(-1)) and 12 h (4.76 g COD L(-1) day(-1)). The condition of 8.22 g COD L(-1) day(-1) (AR-EPHS) showed the best performance with respect to the following parameters: applied volumetric organic load of 7.56 g COD L(-1) day(-1), yield between produced methane and removed organic material of 0.016 mol CH4 g COD(-1), CH4 content in the produced biogas of 85 %, and molar methane productivity of 127.9 mol CH4 m(-3) day(-1). In addition, a kinetic study of the process confirmed the trend that, depending on the biodegradability characteristics of the wastewaters used, the two-step treatment (acidogenic for biohydrogen production and methanogenic for biomethane production) has potential advantages over the single-step process.
authors.affiliation: Escola de Engenharia Mauá, Instituto Mauá de Tecnologia (IMT), Praça Mauá 1, CEP 09.580-900, São Caetano do Sul, SP, Brazil.
authors.forename: T G
authors.initials: TG
authors.lastname: Lullio
authors.forename: L P
authors.initials: LP
authors.lastname: Souza
authors.forename: S M
authors.initials: SM
authors.lastname: Ratusznei
authors.forename: J A D
authors.initials: JA
authors.lastname: Rodrigues
authors.forename: M
authors.initials: M
authors.lastname: Zaiat
mesh_terms: D001421:Bacteria, Anaerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D006859:Hydrogen / Q000302:isolation & purification / Q000378:metabolism*; D007220:Industrial Waste / Q000517:prevention & control*; D008697:Methane / Q000302:isolation & purification / Q000378:metabolism*; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification / Q000379:methods*
chemical_list: D006859:Hydrogen; D007220:Industrial Waste; D008697:Methane; D062065:Wastewater