纳滤生产再生水示范工程运行效果分析

Operation effect of a nanofiltration demonstration project for producing reclaimed water

纳滤(NF)作为一种深度处理工艺,在再生水生产领域具有广阔应用前景,但目前其在生活污水深度处理方面的工程应用不多。为此,对北京市某再生水厂的NF示范工程进行了跟踪研究,评价了NF工艺对各水质指标的去除效果及稳定性。结果表明:该示范工程的NF工艺可以有效地去除化学需氧量(COD)、总磷(TP)、重金属等指标,使出水的这些指标达到《地表水环境质量标准》中Ⅲ类水的相关标准;但对TN的截留能力较差,截留率不足15%,为出水达标的限制因子;NF工艺对大部分微量有机污染物的截留率在70%以上,但对于双酚A和卡马西平截留率较低,分别只有64.1%和53.4%,截留率与目标物分子质量大小及带电情况有关。细菌发光实验结果表明,NF工艺可以保障出水达到无毒状态。

As a promising advanced treatment process,nanofiltration（NF） is seen very competitive for producing reclaimed water. But so far,NF has rarely been used in municipal wastewater reclamation plants. In this paper,we tested the efficiency and stability of a pioneering NF demonstration project in Beijing,which targets producing reclaimed water from municipal wastewater. Results showed that the NF process can effectively remove chemical oxygen demand（COD）,total phosphorus（TP） and heavy metals,with corresponding index of effluent meeting the requirement of the surface water standards,class Ⅲ. However,NF had relatively poor performance for total nitrogen（TN） removal,with a removal rate of less than 15%. The rejections of all trace organics were about or higher than 70% except for bisphenol A and carbamazepine,likely because of the low molecular weight and non-ionic properties of these two chemicals. Luminescent bacteria toxicity test proved the reliability of NF to produce nontoxic effluent.