title: Chlorine inactivation of Tubifex tubifex in drinking water and the synergistic effect of sequential inactivation with UV irradiation and chlorine.
abstract: The inactivation of Tubifex tubifex is important to prevent contamination of drinking water. Chlorine is a widely-used disinfectant and the key factor in the inactivation of T. tubifex. This study investigated the inactivation kinetics of chlorine on T. tubifex and the synergistic effect of the sequential use of chlorine and UV irradiation. The experimental results indicated that the Ct (concentration × timereaction) concept could be used to evaluate the inactivation kinetics of T. tubifex with chlorine, thus allowing for the use of a simpler Ct approach for the assessment of T. tubifex chlorine inactivation requirements. The inactivation kinetics of T. tubifex by chlorine was found to be well-fitted to a delayed pseudo first-order Chick-Watson expression. Sequential experiments revealed that UV irradiation and chlorine worked synergistically to effectively inactivate T. tubifex as a result of the decreased activation energy, Ea, induced by primary UV irradiation. Furthermore, the inactivation effectiveness of T. tubifex by chlorine was found to be affected by several drinking water quality parameters including pH, turbidity, and chemical oxygen demand with potassium permanganate (CODMn) concentration. High pH exhibited pronounced inactivation effectiveness and the decrease in turbidity and CODMnconcentrations contributed to the inactivation of T. tubifex.
authors.affiliation: School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha, Hunan, 410114, PR China; Hunan Province Key Laboratory of Water, Sediment Sciences & Flood Hazard Prevention, Changsha, Hunan, 410114, PR China. Electronic address: niexbcslg@163.com.
authors.forename: Xiao-Bao
authors.initials: XB
authors.lastname: Nie
authors.affiliation: School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha, Hunan, 410114, PR China; Hunan Province Key Laboratory of Water, Sediment Sciences & Flood Hazard Prevention, Changsha, Hunan, 410114, PR China.
authors.forename: Zhi-Hong
authors.initials: ZH
authors.lastname: Li
authors.affiliation: School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha, Hunan, 410114, PR China; Hunan Province Key Laboratory of Water, Sediment Sciences & Flood Hazard Prevention, Changsha, Hunan, 410114, PR China.
authors.forename: Yuan-Nan
authors.initials: YN
authors.lastname: Long
authors.affiliation: School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha, Hunan, 410114, PR China; Hunan Province Key Laboratory of Water, Sediment Sciences & Flood Hazard Prevention, Changsha, Hunan, 410114, PR China.
authors.forename: Pan-Pan
authors.initials: PP
authors.lastname: He
authors.affiliation: School of Hydraulic Engineering, Changsha University of Science & Technology, Changsha, Hunan, 410114, PR China; Hunan Province Key Laboratory of Water, Sediment Sciences & Flood Hazard Prevention, Changsha, Hunan, 410114, PR China.
authors.forename: Chao
authors.initials: C
authors.lastname: Xu
mesh_terms: D000818:Animals; D057919:Biological Oxygen Demand Analysis; D002713:Chlorine / Q000494:pharmacology*; D004202:Disinfectants / Q000494:pharmacology*; D004203:Disinfection / Q000379:methods; D060766:Drinking Water; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009391:Nephelometry and Turbidimetry; D009835:Oligochaeta / Q000187:drug effects*; D013696:Temperature; D014466:Ultraviolet Rays; D018508:Water Purification / Q000379:methods*; D060753:Water Quality
chemical_list: D004202:Disinfectants; D060766:Drinking Water; D002713:Chlorine
keywords: Chlorine inactivation; Inactivation kinetics; Synergistic effect; T. tubifex; UV irradiation