该文以排洪期东江水为原水，开展了聚四氟乙烯（PTFE）中空纤维膜组合工艺处理受污染原水的小试和中试研究。工艺将臭氧、混凝与膜过滤集成，后置生物活性炭过滤。试验的PTFE膜孔径为0．12μm，外径×内径为2．3 mm ×1 mm。小试试验测得临界膜通量为60 L/m2·h，臭氧能够促进组合工艺对有机物的去除，并能提高氨氮的去除。中试试验规模为120 t/d，膜通量为41．67 L/m2·h。结果表明，投加臭氧时组合工艺对氨氮的处理负荷能提高至3．19～4．31 mg/L，COD去除率为70％～94％，UV254去除率达到73％～87％，工艺出水浊度＜0．2 NTU，大于2μm颗粒数＜50 CNT/mL。工艺出水中THMs、HAAs、甲醛、溴酸盐均符合新的饮用水卫生标准；膜出水未检出细菌总数和总大肠菌群数。投加臭氧（O3/TOC＝0．6～0．8）可显著减轻膜污染，达到同样的污染程度所需的运行时间较未投加臭氧时延长1倍；投加7～9 mg/L臭氧可逐渐消除膜污染，达到原位修复膜污染，减少化学清洗频次的目的。%A hybrid process combining oznation with polytetrafluoroethylene (PTFE)hollow fiber membrane was studied for treatment of drinking water from polluted surface water in small and pilot scale. Raw water was simulated the Dongjiang River in flood drainage period. Ozonation,coagulation and membrane filtration were integrated followed by biological activated carbon filtration. The tested PTFE membrane has a pore size of 0. 12μm,out diameter of 2. 3 mm and inner diameter of 1 mm. The results of lab-scale experiment show that the critical flux is 60 L/m2 · h,and the removal efficiencies of organic matters and ammonia are improved with ozone present. The results of pilot scale experiments scale 5 m3/h,permeation flux 41. 67 L/m2 ·h show that the removal load of ammonia is 3. 19~4. 31 mg/L,and the removal efficiencies of COD and UV254 are 70% ~94% and 73% ~87%,respectively;the turbidity of the effluent is below 0. 2 NTU,and the particle number in the effluent is less than 50 CNT/mL. The concentration of THMs,HAAs, bromate and formaldehyde in the effluent are below the standard limits,and the total bacterial counts and coliform counts are not detected. It can be concluded that the addition of ozone (O3/TOC=0. 6~0. 8)can mitigate membrane fouling substantially during the operation and reduce the frequency of membrane cleaning to the half;dosage of 7 ~9 mg O3/L can eliminate membrane fouling gradually without taking out the membrane,thus chemical cleaning frequencies are decreased.
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