在线混凝—超滤—反渗透组合工艺处理MBR出水的中试研究

Pilot study on treating effluent of MBR by combined process of on-line coagulation—UF—RO

建立了以混凝—超滤—反渗透组合工艺处理MBR出水的研究设备。研究表明,该组合工艺具有分离有机污染物和脱盐效果,对TOC、电导率、CODMn、UV254、浊度、总碱度、总硬度的去除率分别达到93.95%、98.94%、90.69%、99.83%、93.41%、89.21%、97.94%。产水电导率≤10μS/cm,可满足部分行业的纯水使用要求。同时,在线投加7mg/LFeCl3和0.35mg/L聚丙烯酰胺(PAM)时,超滤对浊度、UV254、CODMn的去除率分别为82%、20.5%、32.2%,跨膜压差增长趋势减缓,膜污染速率降低,节约了清洗膜的药剂,延长了超滤膜使用寿命,对反渗透膜也具有保护作用。

A pilot-scale combined water treatment facility of coagulation, ultrafiltration （UF）,and reverse osmosis（RO）was set up. It has a high ability of desalinating and removing organics, m terms of the high removal rate of TOC 93. 95%, conductivity 98. 94%, COI）Mn 90. 69%, UV254 99.83%, turbidity 93.41%, total alkalinity 89. 21%, and total hardness 97. 94%, respectively. The results showed that the conductivity of effluent was below 10 μS/cm, which could meet the pure water requirements for some industries. When 7 mg/L FeC13 and 0. 35 mg/L PAM were added, the removal rate of turbidity, UV254 and CODMn is 82%, 20. 5% and 32. 2% respectively. The results indicated that on-line coagulation--UF--RO process had high removal efficiency for turbidity and organics, and also alleviated the climbing trend of transmembrane pressure （TMP） while resisting to membrane fouling at the same time. In addition, this process has a promising engineering application, which can not only save the dosage for cleaning UF membrane but also prolong the life of membrane and protect the RO membrane.