Impurities in Salt Crystal

Abstract

Potassium, magnesium, calcium and sulfate in salt crystal were determined in a case of a combined process of electrodialysis with ion-exchange membrane and multi effect pan. And fluctuation of impurity content was discussed in connection with concentration of mother liquor and particle.
1) Potassium content is 300 to 1,600 ppm. These values are in proportion to concentration of Inother liquor.
2) Sulfate content is 100 to 500 ppm. These values increase with smalier particle size. And the increase in bittern pan is remarkable.
3) Caicium salt, except calcium sulfate, is 30 to 140 ppm. These values increase with concentratiop of mother liquor.
4) Magnesium content is below 10 ppm, which will exist in liquor in crystal.