超滤工艺净化微污染原水的试验研究

采用混凝沉淀-超滤工艺对微污染原水进行试验,对组合工艺的除污染特性进行了研究。结果表明,组合工艺对浊度、颗粒物和藻类的去除效果非常好。出水浊度稳定在0.1NTU以下,水中粒径>2μm的颗粒数约19个/mL,藻类平均数量约为2.2×104个/L。在去除有机物方面,组合工艺对高锰酸盐指数、UV254和DOC的去除率分别为38.0%、15.2%和32.6%,其中对高锰酸盐指数的去除效果较为突出,出水高锰酸盐指数浓度为2.69~2.87mg/L。组合工艺去除的有机物是分子量大于3KD的大分子有机物,对小分子有机物去除效果不明显。其中,混凝沉淀主要去除了水中的疏水性有机物和亲水荷电有机物,超滤膜去除的有机物则以亲水中性有机物为主。在工艺运行期间,超滤膜的跨膜压差增加了约12.3%,跨膜压差的升高主要由被超滤膜吸附的小分子有机物产生。

Study on Ultrafiltration Process for the Treatment of Micropolluted Water

A process of coagulation/sedimentation/ultrafthration was used for the treatment of micro-polhited source water,and the polhiumts removal was investigated.Results showed that the process had a high removal efficiency for turbidity,particles and algae.The effluent turbidity was below 0.1NTU,the number of particle bigger than 2μm Was about 19connts/mL,and the algae were 2.2×10~4 counts/L.In organics removal,the process reduced 38%,15.2%and 32.6%of COD_(Mn),UV_(254) and DOC respectively.It had a prominent high removal ram for COD_(Mn),and the effluent COD_(Mn) was 2.69-2.87mg/L.The combined process removed most organics with molecular weight of more than 3KD.and the small organics was difficult to be removed.The coagulation/sedimentation process removed most hydrophobic organics and hydrophilic polar organics,while the ultrafiltrafion mainly removed hydrophilic neutral organics.The trans-membrane pressure increased about 12.3% during the process operation,which was caused by the adsorption of small organics.