农村饮水降氟设备运行效果研究

目的探讨农村饮水降氟设备降氟水的水质特性以及降氟效果.方法2002-2004年,选择应用电渗析和反渗透技术进行饮水降氟的天津市农村为调查地区.选择某县运行2～3 a的4座电渗析除氟站和6座反渗透除氟站开展调查.同时在其他县选择3座活性氧化铝除氟站和2座纳滤除氟站进行了调查.水质指标包括:pH值、浊度、溶解性总固体(TDS)、总硬度、氟化物、硫酸盐、铝.水质分析和评价依据<生活饮用水卫生规范>(2001).结果反渗透降氟设备和电渗析降氟设备均可以使水氟浓度降低至1.0 mg/L以下,去除率分别为90.01%和75.32%,总硬度、TDS也有不同程度下降,去除率为75.83%～93.48%.纳滤降氟设备也可以使水氟降低至1.0mg/L以下,去除率为75.16%,总硬度、TDS也有不同程度下降,去除率为77.22%和64.90%.结论该次调查的电渗析、反渗透和纳滤设备效果可靠,在技术上适用于不同TDS含量的农村饮水降氟.但反渗透降氟水在降氟的同时,去除水中大部分人体必需微量元素,长期饮用的健康效应有待进一步开展研究.

Efficiency of Drinking Water Defluoridation Facilities Used in Rural High Fluoride Areas

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.