纳滤用于废混酸处理的工业化测试研究

摘要

采用PES纳滤膜对不锈钢酸洗废液进行回收处理,在1.6～3.8 MPa的常温生产工况下进行全样本检测和回归分析,结果表明:废混酸中游离硝酸的浓度变化对金属离子的渗透率无明显影响；废混酸中金属离子含量变化时,渗透液中的金属离子也同步呈现正比例关系.纳滤对于废混酸的金属离子拦截率为20％～30％；游离硝酸的渗透率在80％～95％之间.纳滤膜用于不锈钢酸洗废液回收处理时,由于金属离子高导致酸不平衡而外排,必须采取措施提高金属离子拦截率,否则将制约纳滤膜在不锈钢废混酸回收领域的工业化应用.%PES nano-filtration (NF) membrane is used for the recovery processing of stainless steel pickling waste liquid.Under the production conditions as follows:pressure 1.6-3.8 MPa and normal temperature,total sample detection and regression analysis have been carried out.The results show that the concentration changes of free nitric acid in the waste mixed acid does not have obvious influence on the permeability of metallic ions.When the metallic ions content in waste mixed acid changes,the metallic ions in the penetrating liquid have proportional relationship synchronously.The interception capability of nano-filtration membrane for metallic ions in waste mixed acid is 20％-30％,and the penetrating rate of free nitric acid is between 80％-95％.When nanofiltration membrane is applied to the recovery processing of stainless steel pickling waste liquid,measures must be taken to improve the metallic ion interception rate,because the high content of metallic ions results in the unbalancedness of acid and excretion of acid.Otherwise the industrial application of nano-filtration membranes to the recovery of stainless steel waste mixed acid will be restricted.