膜分离技术深度处理造纸废水的研究

Study on the Advanced Treatment of Papermaking Effluent by Membrane Separation Technology

以二级生化处理后的造纸废水为研究对象,探讨了絮凝沉淀预处理和膜分离技术深度处理造纸废水的最佳工艺条件。研究结果表明,在阳离子聚丙烯酰胺添加量1.5 mg/L、聚合氯化铝铁添加量150 mg/L的条件下进行絮凝预处理时,絮凝效果能达到超滤膜进水要求。超滤膜操作压力控制在0.04～0.10 MPa、膜通量在12～17 L/h时,膜处理性能较好。废水经过超滤、纳滤和反渗透处理后,电导率降到12μS/cm左右,TDS去除率达98%左右,CODCr去除率达90%以上,废水浊度已检测不到,完全达到生产回用水质标准。

The optimum condition for the advanced treatment of the papermaking effluent from secondary biochemical treatment stage by using flocculation precipitation pretreatment and membrane separation technology was studied. The result showed that polyacrylamide （CPAM） and poly aluminum ferric chloride （PAFC） were 1.5 and 150 mg/L respectively, the effluent could meet the requirements of ultra_filtration （UF） after flocculation. The filtration efficiency was better when operating pressure of ultrafiltration membrane was at 0. 04 -0.10 MPa, the membrane flux was between 12 - 17 L/h. The effluent after nanofiltration （NF） treatment and reverse osmosis （RO）, electrical conductivity droped to about 12 I^S/cm, the CODc, removal reached more than 90%, the turbidity of the effluent was undetectable, the treated water quality was close to or even better than the clean water, and fully met the quality standards of reused water. The CODcr of concentrated water was 85.3 mg/L after the RO treatment and met the requirement of the new National Papermaking Industry Effluent Pollutants.