纳滤法去除中低放射性废水中钴离子的研究

研究纳滤法对模拟核电站中、低放射性水平废水中痕量Co2+的去除效果,采用NFW-2B平板聚酰胺纳滤复合膜,考察了压力、pH、无机离子干扰和投加有机络合剂等情况下对膜通量和Co2+去除率的影响。结果表明,随着压力的升高,膜通量增大,截留率在一定压力范围内先增大后降低;pH对膜通量影响不大,在25℃、pH=10附近时,截留效果最佳;在以聚丙烯酰胺作为络合剂的情况下,pH=7、装载量比为0.25时得到较好的去除效果,有效截留率达到98%以上。

REMOVAL OF COBALT IONS FROM LOW AND MEDIUM LEVEL RADIOACTIVE WASTWATER BY NANOFILTRATION

The aim of the present work was to investigate the elimination effect of nanofiltration to remove trace-amount cobalt ions from low and medium level radioactive wastewater.It studied the flux and removal rate of cobalt ions in several conditions such as pressure,pH,competing ions and complex agent.The experimental results showed that with increasing operating pressure,the permeate flux increased and the rejection of cobalt ions initially increased,and then decreased;the pH had no significant effect on the permeate flux.The highest rejection was at pH 10,25 ℃.When pH at 7,the Co2+-to-PAM ratio was 1:4,the highest rejection was obtained,which exceed 98%.