Method and device for refining brine applied to chlorine alkali industry

The invention relates to a method and a device for refining brine applied to the chlorine alkali industry, and belongs to the technical field of the chlorine alkali industry. The method includes steps of firstly, carrying out impurity removal cationic treatment on the brine; secondly, filtering the treated brine by the aid of nano-filtration membranes to obtain refined brine. The brine contains organic pollutants. The method and the device for refining the brine have the advantage that the problem of low electrolytic efficiency of ionic membranes due to brine with organic pollutants in the chlorine alkali industry can be effectively solved by the aid of the method and the device.