title: Influence of the agitation rate on the treatment of partially soluble wastewater in anaerobic sequencing batch biofilm reactor.
abstract: This work reports on the influence of the agitation rate on the organic matter degradation in an anaerobic sequencing batch reactor, containing biomass immobilized on 3 cm cubic polyurethane matrices, stirred mechanically and fed with partially soluble soymilk substrate with mean chemical oxygen demand (COD) of 974+/-70 mg l(-1). Hydrodynamic studies informed on the homogenization time under agitagion rates from 500 to 1100 rpm provided by three propeller impellers. It occurred very quickly compared to the total cycle time. The results showed that agitation provided good mixing and improved the overall organic matter consumption rates. A modified first-order kinetic model represented adequately the data in the entire range of agitation rate. The apparent first-order kinetic constant for suspended COD rose approximately 360% when the agitation rate was changed from 500 to 900 rpm, whereas the apparent first-order kinetic constant for soluble COD did not vary significantly.
authors.affiliation: Departamento de Hidráulica e Saneamento, Escola de Engenharia de São Carlos, Universidade de São Paulo (USP), Av. Trabalhador São-Carlense 400, CEP 13566-590, São Carlos, Sao Paulo, Brazil.
authors.forename: Samantha Cristina
authors.initials: SC
authors.lastname: Pinho
authors.forename: Suzana Maria
authors.initials: SM
authors.lastname: Ratusznei
authors.forename: José Alberto Domingues
authors.initials: JA
authors.lastname: Rodrigues
authors.forename: Eugenio
authors.initials: E
authors.lastname: Foresti
authors.forename: Marcelo
authors.initials: M
authors.lastname: Zaiat
mesh_terms: D001421:Bacteria, Anaerobic / Q000254:growth & development / Q000502:physiology; D018533:Biomass; D019149:Bioreactors; D007700:Kinetics; D009930:Organic Chemicals / Q000378:metabolism; D012995:Solubility; D014865:Waste Disposal, Fluid / Q000379:methods*; D014872:Water Movements
chemical_list: D009930:Organic Chemicals