吸附-超滤工艺用于饮用水除氟的试验研究

Study of Adsorption/Ultrafiltration Process for Fluoride Removal from Drinking Water

采用吸附-超滤工艺进行饮用水除氟的试验研究,试验在恒流条件下进行,重点考察吸附剂粒径、膜区曝气量和回流量对除氟效果和膜污染的影响.结果表明,粉末状的活性氧化铝较颗粒状吸附容量有了很大的提高.在膜通量为150 mL/min,反冲周期为6 h,反冲时间为2 min,反冲流量为150 mL/min,原水ρ（氟）为2 mg/L,活性氧化铝投加量为0.1 g/L的条件下,选取活性氧化铝粒径为0.050-0.074 mm,膜区不曝气,沉淀区与反应区间的回流比为0.5（对应的回流量为4.5 L/h）,可获得较好的除氟效果,并能有效地控制膜污染,使该系统在一定时间内稳定运行.

In this study, an adsorption-ultrafiltration process was adopted for fluoride removal from drinking water. Experiments were carried out at constant current conditions, focusing on the effect of the particle size, aeration and recycling flux on the fluoride removal and membrane fouling. The results showed that the adsorption capacity of powder activated alumina was greatly improved compared to the granular one. With flux at 150 mL/min, backwashing cycle of 6 h, backwashing time of 2 min, backwashing flow at 150 mL/min, raw fluoride mass concentration of 2 mg/L, activated alumina dosage of 0.1 g/L, activated alumina particle size of 0.050-0.074 mm, no aeration, and a reflux ratio between precipitation and reaction section of 0.5, a better result of fluoride removal and effective control of the membrane fouling could be achieved. Under these conditions, the system could operate stably for a certain period of time.