中文摘要：

采用腐殖酸（HA）配水考察混凝剂类型和投加量对水中有机污染物去除效果、膜污染构成及发展规律的影响，并探讨絮体粒径、密实度等形态特征与絮体滤饼层阻力间的内在联系。结果表明：PAC和FeCl3作为混凝剂均能有效地去除水中的HA，但以FeCl3作为混凝剂时膜污染更加严重。在较低混凝剂投加量下，PAC和FeCl3产生的絮体细小，容易形成致密滤饼层，导致过滤阻力增大；随着混凝剂投加量的增加，絮体更容易碰撞成长，粒径增大，形成结构疏松的滤饼层，减小过滤阻力；与PAC相比，FeCl3絮体结构更加密实，因此滤饼层导致的膜污染更加严重。

英文摘要：

The effects of coagulant type and its dosage on organic matter removal and membrane fouling were investigated as well as the underlying correlation between the floc characteristics and cake layer resistance. Water spiked with humic acid （HA） was used as the influent of a coagulation-ultrafiltration system, and two coagulants, namely PAC and FeCl3, were tested individually. The results indicated that either PAC or FeCl3 was able to remove humic acid effectively;however,more serious fouling on membrane surface was detected in the case of FeCl3. At lower coagulant dosage levels, the flocs were smaller, which led to denser cake layer on the membrane surface and more serious membrane fouling. With the increase of dosage, flocs turned to be more possible to become larger in size, and the consequent cake layer was looser. As a result, the filtration resistances decreased. Compared with PAC, FeCl3 formed flocs with denser structure, and the membrane fouling of the cake layer was therefore stronger.