title: Color, organic matter and sulfate removal from textile effluents by anaerobic and aerobic processes.
abstract: An upflow anaerobic sludge blanket (UASB)-submerged aerated biofilter (SAB) system was evaluated to remove color and chemical oxygen demand (COD) from real textile effluent. The system was operated for 335 days in three phases (P-1, P-2, P-3) with total hydraulic retention time varying from 21 h to 14 h. The results showed that high sulfate levels (>300 mg SO4(2-)/L) impaired the dye reduction. The best color removal efficiencies of 30% and 96% for the UASB and the reactor system, respectively, were obtained in P-1; the SAB higher efficiency was associated with adsorption. The best COD removal efficiency of 71% for the reactor system was obtained in P-2. Precipitation of some material composed mostly of sulfur (98%) and some metals occurred in the UASB. However, the precipitated sulfur was again oxidized in the SAB. The system also showed an effective toxicity reduction in tests (Daphnia magna) with the treated effluent.
authors.affiliation: Laboratory of Environmental Sanitation, Department of Civil Engineering, Federal University of Pernambuco, Av. Acadêmico Hélio Ramos, s/n. Cidade Universitária, Recife, PE CEP: 50740-530, Brazil.
authors.forename: F M
authors.initials: FM
authors.lastname: Amaral
authors.affiliation: Laboratory of Environmental Sanitation, Department of Civil Engineering, Federal University of Pernambuco, Av. Acadêmico Hélio Ramos, s/n. Cidade Universitária, Recife, PE CEP: 50740-530, Brazil.
authors.forename: M T
authors.initials: MT
authors.lastname: Kato
authors.affiliation: Laboratory of Environmental Sanitation, Department of Civil Engineering, Federal University of Pernambuco, Av. Acadêmico Hélio Ramos, s/n. Cidade Universitária, Recife, PE CEP: 50740-530, Brazil.
authors.forename: L
authors.initials: L
authors.lastname: Florêncio
authors.affiliation: Laboratory of Environmental Engineering, Academic Center of Agreste, Federal University of Pernambuco, Rodovia BR-104, Km 62, Nova Caruaru, Caruaru, PE CEP: 55002-970, Brazil. Electronic address: savia@ufpe.br.
authors.forename: S
authors.initials: S
authors.lastname: Gavazza
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D003116:Color; D005232:Fatty Acids, Volatile / Q000138:chemical synthesis; D005374:Filtration / Q000379:methods; D009930:Organic Chemicals / Q000302:isolation & purification*; D012722:Sewage; D013431:Sulfates / Q000302:isolation & purification*; D013783:Textile Industry; D062065:Wastewater
chemical_list: D005232:Fatty Acids, Volatile; D009930:Organic Chemicals; D012722:Sewage; D013431:Sulfates; D062065:Wastewater
keywords: Anaerobic–aerobic treatment; Azo dye; Real textile wastewater; Salinity; Sulfate