三种长江原水水质与混凝效果的比较

Comparison of Water Quality and Coagulation Effects on Three Kinds of Yangtze River Raw River

夏季同一时期3种长江原水浊度和氨氮较低,中央沙库区原水藻类和高锰酸盐指数较高。有机物图谱分析表明,3种原水中多以苯系物、酞酸酯类等小分子有机物为主,浓度均比较低。混凝剂硫酸铝、聚硫氯化铝和聚合硫酸铝铁对于同种原水浊度的去除效果比较接近,其中聚合硫酸铝铁略好。对于陈行水库原水和青草沙库区原水,硫酸铝的最佳投量为30 mg/L,对于中央沙库区原水,在增加硫酸铝投量或改变混凝剂种类的情况下均难以达到良好的混凝效果,而预加氯工艺可有效改善其混凝效果,提高高锰酸盐指数的去除率。

During the same period of summer,turbidity and ammonia in three kinds of Yangtze water were all low,while algae and CODMn in raw water of Zhongyangsha Reservoir were higher than the other two kinds of raw water.Chromatogram analysis showed that there were mainly benzene,phthalate esters and other small organic molecules in the three kinds of raw water,whose concentrations were low.For turbidity removal of the same kind of raw water,effect of coagulant aluminum sulfate,PAC-S and PAFS were almost the same,and PAFS was a little better.The optimum dosage of aluminum sulfate was 30 mg/L for raw water of Chenhang Reservoir and Qingcaosha Reservoir.As far as raw water of Zhongyangsha Reservoir was concerned,increasing coagulant dosage of aluminum sulfate or changing the coagulant types were both difficult to achieve good coagulation effect,while prechlorination process can improve the coagulation efficiency and CODMn removal.