title: Economical evaluation of sludge reduction and characterization of effluent organic matter in an alternating aeration activated sludge system combining ozone/ultrasound pretreatment.
abstract: An ozone/ultrasound lysis-cryptic growth technology combining a continuous flow anaerobic-anoxic-microaerobic-aerobic (AAMA+O3/US) system was investigated. Techno-economic evaluation and sludge lyses return ratio (r) optimization of this AAMA+O3/US system were systematically and comprehensively discussed. Economic assessment demonstrated that this AAMA+O3/US system with r of 30% (AAMA+O3/US2# system) was more economically feasible that can give a 14.04% saving of costs. In addition to economic benefits, a 55.08% reduction in sludge production, and respective 21.17% and 5.45% increases in TN and TP removal efficiencies were observed in this AAMA+O3/US2# system. Considering the process performances and economic benefits, r of 30% in AAMA+O3/US2# system was recommended. Excitation-emission matrix and Fourier transform infrared spectra analyses also proved that less refractory soluble microbial products were generated from AAMA+O3/US2# system. Improvement in 2,3,5-triphenyltetrazolium chloride electron transport system (TTC-ETS) activity in AAMA+O3/US2# further indicated that a lower sludge lyses return ratio stimulated the microbial activity.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Shan-Shan
authors.initials: SS
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China. Electronic address: guowanqian@hit.edu.cn.
authors.forename: Wan-Qian
authors.initials: WQ
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Yi-Di
authors.initials: YD
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Qing-Lian
authors.initials: QL
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Hai-Chao
authors.initials: HC
authors.lastname: Luo
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Si-Mai
authors.initials: SM
authors.lastname: Peng
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: He-Shan
authors.initials: HS
authors.lastname: Zheng
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Xiao-Chi
authors.initials: XC
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
authors.forename: Nan-Qi
authors.initials: NQ
authors.lastname: Ren
mesh_terms: D000332:Aerobiosis; D064751:Ammonium Compounds / Q000302:isolation & purification; D000693:Anaerobiosis; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D004579:Electron Transport; D009584:Nitrogen / Q000302:isolation & purification; D009930:Organic Chemicals / Q000302:isolation & purification*; D010126:Ozone / Q000737:chemistry*; D010758:Phosphorus / Q000302:isolation & purification; D012722:Sewage / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D013778:Tetrazolium Salts / Q000737:chemistry; D013997:Time Factors; D014465:Ultrasonics / Q000379:methods*; D014865:Waste Disposal, Fluid / Q000191:economics* / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D064751:Ammonium Compounds; D009930:Organic Chemicals; D012722:Sewage; D013778:Tetrazolium Salts; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D010126:Ozone; C009591:triphenyltetrazolium; D009584:Nitrogen
keywords: Combined ozone/ultrasound pretreatment; Economic benefits; Microbial activity; Nutrient removal; Sludge reduction