title: Potential risk and control strategy of biofilm pretreatment process treating raw water.
abstract: An enhanced lab-scale biofilm pretreatment process treating raw water obtained from eutrophicated water bodies was established and started up with a novel strategy of low-level nutrients addition and effluent recirculation. Results showed that the startup strategy was useful for biofilm formation and pollutants removal, but it had the risks of increasing substrate affinity constant (Ks) and biofilm decay in treating raw water. Fortunately, the increased Ks value did not affected the NH4(+)-N removal performance via keeping the NH4(+)-N loading rate larger than 6.29 mg L(-1)d(-1). In addition, lower hydraulic retention time (HRT) favored the removal of organic matters, and the maximum TOC removal rate of 76.5 mg L(-1)d(-1) were achieved at HRT of 2h. After long-term acclimatization at oligotrophic niche, the decrease of Ks value and increase of biomass, extracellular polymeric substances, bioactivity were achieved. Finally, the stable operation of biofilm pretreatment process was realized in treating polluted raw water.
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Guang-Feng
authors.initials: GF
authors.lastname: Yang
authors.affiliation: Department of Environmental Engineering, Zhejiang Ocean University, No. 1 Haida South Road, Zhoushan 316022, China.
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Feng
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Sha-Fei
authors.initials: SF
authors.lastname: Wang
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Jia-Heng
authors.initials: JH
authors.lastname: Zhou
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Cai-Rong
authors.initials: CR
authors.lastname: Guo
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Tian
authors.initials: T
authors.lastname: Xia
authors.affiliation: Haining Second Waterworks Co. Ltd., Haining 314408, China.
authors.forename: Wen-Xiong
authors.initials: WX
authors.lastname: Sun
authors.affiliation: Haining Second Waterworks Co. Ltd., Haining 314408, China.
authors.forename: Yue-Jie
authors.initials: YJ
authors.lastname: Jiang
authors.affiliation: Haining Second Waterworks Co. Ltd., Haining 314408, China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Sun
authors.affiliation: Haining Second Waterworks Co. Ltd., Haining 314408, China.
authors.forename: Lian
authors.initials: L
authors.lastname: Cao
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China.
authors.forename: Xiang-Yang
authors.initials: XY
authors.lastname: Xu
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China. Electronic address: felix79cn@hotmail.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhu
mesh_terms: D018441:Biofilms; D018533:Biomass; D019149:Bioreactors; D014867:Water; D014874:Water Pollutants, Chemical; D014876:Water Pollution; D018508:Water Purification / Q000379:methods*
chemical_list: D014874:Water Pollutants, Chemical; D014867:Water
keywords: Biofilm; Nutrient addition; Potential risk; Pretreatment process; Raw water