Effect of chloride on the formation of volatile disinfection byproducts in chlorinated swimming pools.
Chloride can accumulate in chlorinated swimming pool water. Although substantial efforts have been made to examine the effects of halide ions on the formation of volatile disinfection byproducts (DBPs), most have focused on bromide. The effects of chloride ion concentration on the formation of volatile DBPs in swimming pools remain largely unstudied. In this study, chlorination of typical precursors and body fluid analogue (BFA) were investigated with variable chloride concentration and pH. The formation of three volatile DBPs (NCl3, CHCl3and CNCHCl2) was observed to be linearly correlated with chloride concentration, both in bench experiments and in actual swimming pool water samples. Free chlorine consumption was also observed to increase with chloride concentration. These behaviors appear to be attributable to shifts in speciation of free chlorine, with higher chloride resulting in higher concentration of molecular chlorine (Cl2), which is much more reactive than HOCl. The results of this work suggest that changes in pool management strategies to promote low chloride concentration could be important for control of volatile DBPs in pools and to economize free chlorine usage.
Department of Applied Chemistry, China Agricultural University, Beijing, 100193, China.
Yue
Y
E
Department of Applied Chemistry, China Agricultural University, Beijing, 100193, China.
Hui
H
Bai
Department of Applied Chemistry, China Agricultural University, Beijing, 100193, China.
Lushi
L
Lian
Department of Applied Chemistry, China Agricultural University, Beijing, 100193, China. Electronic address: jli@cau.edu.cn.
Jing
J
Li
Lyles School of Civil Engineering, 550 Stadium Mall Drive, Purdue University, West Lafayette, IN, 47907, USA; Division of Environmental & Ecological Engineering, Purdue University, West Lafayette, IN, 47907, USA.
Ernest R
ER
Blatchley
D002713:Chlorine / Q000737:chemistry; D004202:Disinfectants / Q000737:chemistry; D004203:Disinfection; D054879:Halogenation; D013551:Swimming Pools
D004202:Disinfectants; D002713:Chlorine
Chloride; Chlorination; Swimming pool; Volatile DBPs