Patents
The invention relates to the recovery of industrial-grade potassium chloride and low sodium edible salt from bittern as part of an integrated. The comprises mixing low sulphate concentrated feed bittern (a by-product of salt industry) of density 31.5 to 32.5o Be (sp.gr. 1.277-1.289) with high-density end bittern of density 36.5 to 37.5o B' (sp.gr. 1.336-1.35), thereby producing low sodium carnallite, from which industrial grade potassium chloride is produced. The resultant bittern is evaporated in a forced evaporation system, thereby producing crude carnallite, from which low sodium salt that would be beneficial to persons suffering from hypertension is produced. When sulphate-rich bittern is used, such bittern is desulphated with CaCl2 that is generated from carnallite decomposed liquor through reaction with lime, and wherein low B2O3-containing Mg(OH)2 is a by-product. The entire content of potassium in the feed bittern is recovered in the invention.