摘要：

基于反渗透（RO）膜的双膜组合工艺被广泛应用于废水回用处理，研究了不同RO组合工艺（UF-RO、UF-NF-RO、UF-RO-RO）对化工废水主要污染物的处理效能。通过对不同RO组合工艺处理化工废水过程中膜通量变化、出水中荧光类有机物、膜表面有机和无机污染物含量和成分的分析，揭示了RO膜污染层的形貌和特性。研究结果表明，UF-RO和UF-NF预处理可以一定程度上减缓RO膜通量的下降，但连续运行8 h后RO膜通量仍然严重下降，出水COD、TP、TN均较低，TN去除率均大于95%。废水中荧光类有机物经UF-RO、UF-NF-RO和UF-RO-RO处理后显著减少，主要是由于RO对废水中有机物的截留作用。RO膜表面的污染物主要包括无机污染物质（如钙和镁）以及蛋白质类有机污染物，且有一定量的累积，证明UF、NF、RO等预处理后仍存在污染物质能够在后续RO表面积累，导致严重的膜污染问题。

关键词: 化工废水, 双膜法, 反渗透, 膜污染

Abstract:

The double-membrane combination process based on reverse osmosis (RO) membrane is widely used in wastewater reuse treatment. The treatment efficiency of different RO combination processes (UF-RO,UF-NF-RO,UF-RO-RO) on the main pollutants of chemical wastewater was studied. The morphology and characteristics of the membrane pollution layer were revealed by analyzing the membrane flux in the process of chemical wastewater treatment by different RO combination processes, the amount, content and composition of fluorescent organic matter in the effluent, organic and inorganic pollutants on the membrane surface. The results showed that UF-RO and UF-NF pretreatment could slow down the decline of RO membrane flux, but the membrane flux was still serious after 8 hours. The COD, TP, and TN of effluent were all low, and the TN removal rate was greater than 95%, when the chemical water was treated by double membrane methods. Fluorescent organic matter was significantly reduced in the effluent after UF-RO, UF-NF-RO and UF-RO-RO treatment, mainly due to RO interception of organic matter from wastewater. The pollutants on the surface of the RO membrane mainly included inorganic pollutants (such as calcium and magnesium) and protein-based organic pollutants, and there was a certain amount of accumulation on the subsequent RO surface, which proved that there were still pollutants after UF, NF, RO and other pretreatments, leading to serious membrane fouling problems.

Key words: chemical wastewater, double membrane method, reverse osmosis, membrane fouling

中图分类号: 

• X703