高岭土与腐殖酸对混凝过程中药物去除效能的影响

Influences of kaolin and humic acid on removal of pharmaceuticals in coagulation processes

以对乙酰氨基酚(ACE)、卡马西平(CBZ)、萘普生(NAP)、雌二醇(E2)和双氯芬酸(DCF)5种药物为目标物,采用静态实验,分别投加高岭土和腐殖酸来模拟水源水中的悬浮颗粒和天然有机物,考察了混凝过程中高岭土和腐殖酸投加量对5种目标药物去除效能的影响。结果发现,在未投加高岭土与腐殖酸的去离子水体系中进行硫酸铝混凝实验时,ACE与CBZ 2种药物的最大的去除率都不超过10%,5种药物中疏水性最高的DCF去除效果最好,最高去除率达到了33%;高岭土加入后对ACE与CBZ的去除效率无明显影响,但对NAP、E2与DCF的去除则有显著的促进作用,最大去除率分别达到31.53%、36.46%和52.4%;而在不投加混凝剂时,单独高岭土对5种药物的最大吸附去除率仅有20%左右。腐殖酸与高岭土同时加入后,对E2的混凝去除效果有较明显的抑制作用,但NAP与DCF去除效率却得到了一定程度的增加,最大去除率分别达到了63.5%和66.6%。可见,当水中含有悬浮颗粒物及腐殖酸的情况下,混凝工艺对酸性药物(如NAP及DCF)有较好的去除效果。

The behaviours of five selected pharmaceuticals, including acetaminophen （ACE）, carbamazepine （CBZ）, 17β-Estradiol （E2）, naproxen （NAP） and diclofenac （DCF） in coagulation processes were investigated. Kaolin and humic acid were used in jar tests to simulate suspended solids and natural organic matter respectively to study their influences on the removal of these pharmaceuticals. The results indicated that the maximum removal rates of ACE and CBZ by coagulation were less than 10% in the deionized water for both pharmaceuticals. In the absence of kaolin and humic acid, the highest removal rate among these pharmaceuticals was found in DCF whose maximum rate was around 33%. Kaolin can hardly influence the removal rate of ACE and CBZ. However, it has a positive impact on the removal of NAP, E2 and DCF. The maximum removal rates of these three pharmaceutical reached 31.53%, 36.46% and 52.3%, respectively. The adsorption removal rates of these pharmaceuticals by kaolin alone were nearly 20%. After addition of humic acid, the maximum removal rates of NAP and DCF were nearly 63.5% and 66.6%, respectively, but the removal rate of E2 was somehow restrained. In conclusion, coagulation processes increse the removal rates for some acid pharmaceuticals when suspended solids and humic acid are present in the source water.