三级过滤对复合型微污染地下水净化效能研究

目的研究接触氧化法的工艺过程与运行参数，以使复合型微污染地下水达到饮用水标准．方法用地下水配加MnSO4·5H2O，FeSO4·7H2O，NH4Cl和腐植酸、尿素、淀粉，模拟复合型微污染地下水，采用锰砂-陶粒-锰砂三级接触氧化过滤法处理，滤层总厚度1．5m，滤速1m／h．结果经过三级曝气、过滤后，出水主要指标达到饮用水标准．Fen氧化还原电位低，只采用跌水曝气DO值已满足要求，平均去除率为95．36％．CODMn质量浓度相对较低，在只跌水曝气时已达标，平均去除率为44．21％，增大曝气量后出水质量浓度更低，平均去除率为53．69％．采用简单的跌水曝气方式时，出水锰和氨氮质量浓度均较高，经增加曝气强度后，出水氨氮、锰逐渐开始达标，达标后平均去除率分别为97．22％和96．50％．结论三级曝气、过滤接触氧化法处理复合型微污染地下水能取得良好的净化效果，其中DO对锰和氨氮有较大影响．

Study on Purification Efficiency of Three-Level Filtration for Treating The Composite Micro-Polluted Groundwater

In order to treat the composite micro-polluted groundwater to conform to the standard of drinking water, the process and operating parameters of contact oxidation were studied in this paper. The manganese sand-ceramic-manganese sand consisted of three-level contact oxidation filtration process method was used to treat the composite micro-polluted groundwater that was built through groundwater added MnSO4·5H2O,FeSO4·7H2O,NH4Cl,humic acid,urea and starch. The total thickness of the filter layer was 1.5 m and the filtration velocity was 1.0 m/h. It shows that the main effluent indexes conform to the drinking water standard by three-level aeration and three-level filtration. Because the oxidation-reduction potential is low, Fe^2＋ is easily oxidized ,by simple drop-aeration ,the average removal rate is 95.36% and meets the requirement. Due to the influent CODMn mass concentration is relatively low, the average removal rate achieves 44. 21% by simple drop-aeration. The removal rate can be further improved to 53.69% by increasing the DO content. The mass concentrations of effluent manganese and ammonia nitrogen which treated by simple drop-aeration are higher. After increasing aeration intensity, the effluent mass concentrations can gradually reach the standard of drinking water and average removal rates are 96. 50%, 97.22%, respectively. It concludes that through three-level aeration and three-level filtration contact oxidation process treating, good purification efficiency of the composite micro-polluted groundwater can be obtained. Meanwhile, DO has a great impact on the manganese and ammonia nitrogen removal.