Study on the pollution mechanism of drinking water source water to ultrafiltration membrane

The effects of particulate matter (represented by humic acid, kaolin and algae) on ultrafiltration membranes in micro-polluted water sources were investigated, and the mechanism of ultrafiltration membranes was further understood with the change of membrane flux and transmembrane pressure difference. The results showed that the removal rate of kaolin and algae by UF membrane was over 99%, while the removal rate of humic acid was only about 72%. Moreover, the extent of UF membrane fouling caused by humic acid was larger than that caused by kaolin and algae. The higher the concentration of humic acid, the more serious the membrane fouling was. Ultrafiltration membranes contaminated by humic acid were washed by 0.05mol/L NaOH alkali and 0.05mol/L HCL acid. The permeability of the membranes was restored to 91.24% of the cleaned surface, which was better than that of pure water, sodium hypochlorite and sodium hydroxide. It can provide better guidance for choosing appropriate cleaning agents for ultrafiltration membrane fouling.