多介质过滤—超滤—反渗透法深度处理废水的工艺改进

Improvement of Multi-medium Filtration-Ultrafiltration-Reverse Osmosis Process for Wastewater Advanced Treatment

针对某厂多介质过滤—超滤—反渗透(MMF—UF—RO)废水深度处理工艺发生污堵的问题,采用在MMF装置前加入NaOH混凝沉淀的改进工艺代替加入聚合氯化铝(PAC)絮凝剂的原工艺。模拟原工艺水样的初始UF膜通量较低,过滤后UF膜通量下降35%左右;模拟改进工艺水样的初始UF膜通量较高,且UF膜通量基本无变化。改进工艺UF装置出水中除SiO_2外,其他物质的质量浓度远小于原工艺UF装置出水,可有效改善RO装置的进水水质。改进工艺的MMF和UF的运行稳定性均明显优于原工艺。

To resolve the fouling problem occurred in the advanced treatment of wastewater by multimedium filtration - ultra filtration - reverse osmosis process （ MMF - UF - RO） in a plant, NaOH coagulation precipitation before MMF was used instead of the original PAC flocculation precipitation. The UF membrane flux of the simulated original process is lower at the beginning and then decreased by 35% ; while that of the simulated improved process is higher and stable. The mass concentration of the components except SiO2 in the UF effluent of the improved process is far less than that of the original process, which indicates that the water quality of the RO influent can be improved effectively. The operation stabilities of MMF and UF of the improved process are both significantly better than those of the original process.