title: [Preparation of a composite coagulant from fly ash and its application in domestic wastewater treatment].
abstract: Fly ash was investigated as a raw material for the preparation of a composite coagulant with sulfuric acid. Types of acid solution, H2SO4 concentration, ratio of H2SO4 to fly ash and stirring time were respectively examined as factors that influenced the efficiency of converting the iron and aluminum components into a composite coagulant and coagulation performance on domestic wastewater. The coagulant was attained at the condition of H2SO4-fly ash ratio of 5 mL/g, H2SO4 of 2 mol/L, stirring time of 4h and stabling time of 30 min, and contained Fe3+ of 0.010 8 mol/L with conversion efficiency of 11.4% and Al3+ of 0.035 4 mol/L with conversion efficiency of 4.3%. Removal efficiencies of COD and SS by this type of coagulant reached 70.4% and 91.9% respectively when treating domestic wastewater. This study provides a promising means to utilize fly ash for coagulation, which possibly makes wastewater treatment more economical and more sustainable.
authors.affiliation: State Key Laboratory of Urban Water Resources and Environment, School of Municipal & Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Ya-Qiang
authors.initials: YQ
authors.lastname: Li
authors.forename: Kai
authors.initials: K
authors.lastname: Hu
authors.forename: Qing-Liang
authors.initials: QL
authors.lastname: Zhao
authors.forename: Feng
authors.initials: F
authors.lastname: Tang
authors.forename: Zhi-Gang
authors.initials: ZG
authors.lastname: Liu
authors.forename: Fu-Yi
authors.initials: FY
authors.lastname: Cui
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D060729:Coal Ash; D005427:Flocculation; D007501:Iron / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry; D052638:Particulate Matter / Q000737:chemistry*; D015203:Reproducibility of Results; D013464:Sulfuric Acids / Q000737:chemistry; D013499:Surface Properties; D014865:Waste Disposal, Fluid / Q000191:economics / Q000379:methods*
chemical_list: D060729:Coal Ash; D009930:Organic Chemicals; D052638:Particulate Matter; D013464:Sulfuric Acids; D002244:Carbon; D000535:Aluminum; D007501:Iron