Efficiency of Drinking Water Defluoridation Facilities Used in Rural High Fluoride Areas / 环境与健康杂志

ABSTRACT

Objective To understand the efficiency of defluoridation facilities used in drinking water defluoridation in the rural high fluoride areas in Tianjin and the sanitary characteristics of treated drinking water. Methods The raw water samples and treated water samples were collected from 4 water stations where the electrodialysis technics was applied and 6 water stations where the reverse osmosis technics was applied and the facilities had been operated for 2-3 years in a county, as well as 3 water stations applied activated aluminium oxide adsorption technics and 2 water stations applied nanofiltration membrane technics in the other counties in Tianjin in 2002-2004. The pH value,turbidity, total dissolved solids, total hardness, fluoride, sulfate, aluminium, in all water samples were determined and evaluated according to the Sanitary Standard for Drinking Water(2001). Results The treated water samples from electrodialysis and reverse osmosis defluoridation facilities showed lower fluoride level(below 1.0 mg/L with fluoride removal rates of 90.01% and 75.32%),and lower total dissolved solids and total hardness levels with removal rates of 75.83%-93.48%. The treated water samples from nanofiltration membrane defluoridation facilities also showed lower fluoride level(below 1.0 mg/L with fluoride removal rates of 75.16%,and lower total dissolved solids and total hardness levels with removal rates of 64.90% and 77.22% respectively. Conclusion The investigated electrodialysis, reverse osmosis and nanofiltration membrane defluoridation facilities show a reliable efficiency and are suitable for application of removal of fluoride in drinking water with different levels of total dissolved solids in the rural high fluoride areas. The effects of defluoridated water produced by reverse osmosis defluoridation facilities on human health need to be studied further more.