中文摘要：

以城市景观水体净化为目标,考察混凝除藻同时去除氮元素的特性和影响因素.结果发现,水体内较高的DOC（溶解性有机质）含量会阻碍藻浊度的去除.聚合氯化铝（PACl）以及PACl与硫酸铝（Alum）的复合剂（PACl＋Alum）对藻浊度的去除效果均相对单独使用PACl或Alum较好,其中PACl＋Alum对其他物质（如氮、DOC等）的去除效果也相对单独使用PACl或Alum更佳;在同样的最佳投药量时,低pH条件能获得更好的藻浊度去除率;对氮元素去除的进一步研究发现,DON（溶解性有机氮）的去除特征和过程与TN（总氮）非常一致,表明该水体TN的去除主体上是通过DON的去除实现的;低pH条件同样有利于氮和DOC的去除;但DOC与DON去除的不同步性,说明DOC中的DON成分和性质是非均一性的,是未来可进一步深入研究的重要方向.

英文摘要：

With the cleaning of urban landscape waters as the objective,the removal of algae and nitrogen by coagulation was investigated.The results showed that high DOC concentration inhibits the removal of algae.A composite of polyaluminium chloride（PACl） and Alum as well as PACl were better than other flocculants（Alum and FeCl3） in removing algae turbidity from urban landscape waters.PACl＋Alum was also better in the removal of nitrogen and dissolved organic carbon（DOC）.Under a certain flocculant dosage,a lower pH benefited the removal of algae,DOC and even dissolved organic nitrogen（DON）.For this kind of water,the removal processes of total nitrogen（TN） and DON were well correlated,indicating that the removal of TN was mainly through the removal of DON.However,the removal process of DON was not synchronous with that of DOC,illustrating a heterogeneous composition of DON in DOC.This needs to be investigated by further research in the future.