液液萃取法处理变压器油中铜铁离子的研究

Removal of Copper and Iron Ion from Transformer Oil by Liquid-Liquid Extraction

铜离子过量会导致变压器油介质损耗因数增加,通过N-甲基吡咯烷酮(NMP)-水萃取体系对铜铁含量较高的变压器油进行萃取,研究萃取次数、温度、含水量对液液萃取效果的影响,同时对萃取前后绝缘油中添加剂的含量和电气性能指标变化进行分析。结果表明:采用NMP-水萃取3次可以使变压器油中铜铁离子含量大幅降低,介质损耗因数明显下降;该萃取体系有较宽的温度适用范围;NMP体系中加入微量水能增强铜铁离子的去除能力;经过NMP液液萃取后,绝缘油中的添加剂含量下降。

Excessive copper ions would lead to the increase of dielectric dissipation factor of transformer oil. So we used N-methyl-2-pyrrolidone（NMP）-water system to extract the copper and iron ions in transformer oil in this paper,studied the influence of extraction times,temperature,and water content on the liquid-liquid extraction effect,and analyzed the variation of additives content in the transformer oil and its electrical properties before and after extraction. The results show that the copper and iron ions content decrease obviously after three times of extraction,and the dielectric dissipation factor decreases greatly. The extraction system can be applied in wide range of temperature. The small content of water in the extraction system can enhance the removal ability of copper and iron ions. After liquid-liquid extraction,the additives content decline.