METHOD FOR OBTAINING ENRICHED CARNALLITE Russian patent published in 2019 - IPC C22B3/00 

FIELD: technological processes.

SUBSTANCE: invention relates to a method of producing enriched carnallite, a raw material for producing magnesium metal, in a halurgic scheme by dissolution-crystallisation. Method includes underground dissolution of carnallite or mixed potassium-magnesium ore with recycled solution at temperature of 30–60 °C and weight ratio of magnesium chloride not exceeding 25 %. Solution is evaporated with precipitation and separation of sodium chloride and cooled to obtain a carnallite suspension. When the suspension is separated, carnallite and recycled solution are obtained, which is directed to condensation of steam formed during cooling of the solution, with simultaneous heat recovery, and then combined with a hot suspension of sodium chloride and a steam condensate from the stage of evaporation of the chloromagnesium solution.

EFFECT: obtaining, at underground dissolution of carnallite or mixed potassium-magnesium ore solution with optimum ratio of magnesium and potassium chloride to obtain enriched carnallite with high content of basic substance, low consumption of heat power in form of steam, as well as wasteless production of enriched carnallite.

1 cl