Optimization Research Of Direct Drinking Water System In Primary And Middle Schools Suitable For Removal Of Organic Carbon In Drinking Water

Drinking water safety not only affects the national economy and people's livelihood,but also affects human health and survival.With the development of modern agriculture and industry,the amount of micro-pollutants detected in water sources is increasing,and the quality of drinking water components is more and more complicated.In recent years,in order to provide high quality and safe drinking water to primary and secondary schools,direct drinking water projects have been carried out one after another in the whole country.After tap water depth treatment,it can remove micro-organisms and improve water quality,at the same time,it improves the safety during direct drinking.Jiaxing City is a typical plains river network in the lower reaches of Taihu Lake.The river water is the source of water and the quality of tap water is poor.This paper studied the effluent quality of drinking water system of 4 primary and secondary schools in Jiaxing(Beijing Normal University Affiliated School,Fengqiao Primary School,Qixing Primary School,Experimental Primary School).The results showed that the tap water in Jiaxing had a high concentration of organic matter and the total organic carbon(TOC)was 1.99 mg/L,which was dominated by large molecular weight substances.Drinking water system of four primary and secondary schools on the TOC and UV254 removal rates were below 50%,and affected by the amount of drinking water,direct drinking water system effluent organic concentration is not stable.Concentrated water supply mode disinfection by-products removal effect is better than the Integrated direct drink fountains mode.In the integrated drinking fountains,the removal rates of trihalomethanes(THMs)from the affiliated schools of Beijing Normal University and Fengqiao Primary School were respectively 35.4%?61.6%and 45.9%?58.2%,and the removal rates of halo acetic acid(HAAs)were respectively 66.5%?83.8%? 72.1%?87.8%.The removal rates of THMs in Qixing Primary School and Experimental Primary School were respectively 85.2%?96.1%and 75.4%?93.8%,and the removal of HAAs rates were respectively 88.1%?92.0%and 84.5%?89.1%,which much higher than the one integrated water dispenser.In addition,after weekends or long holidays,it generally need to use disinfectant to chean the straight drinking fountains pipe And the tests showed that after disinfection of chlorinated water disinfection byproduct concentration increased significantly,so it needs to be fully cleaned before the water supply.In order to further improve the ability of direct drinking water system to remove organics in tap water and further improve the quality of direct drinking water,we screened 13 kinds of activated carbon in the market for dynamic adsorption test.On this basis,activated carbon in direct drinking water system was optimized.The results showed that the removal efficiency of TOC,UV254 and disinfection by-products of the domestic purified granular activated carbon XC was much better than that of the commonly used imported Calgon activated carbon.In the integrated mode,When the water passed through to 5400L,the removal rate of XC activated carbon units to TOC was 70.14%,the removal rate of UV254 was 82.14%and the removal rate of disinfection byproducts(THMs,HAAs)were respectively 100%and 84.91%.In the centralized water supply mode,the removal rate of XC activated carbon units to TOC was 78.12%,the removal rate of UV254 is 83.37%and the removal rate of disinfection by-products(THMs,HAAs)was respectively 100%and 85.53%.XC activated carbon units Plays a significant optimization effect on active carbon unit of the direct drinking water system.