VACUUM-CRYSTALLIZATION UNITS FOR THE PRODUCTION OF MAGNESIUM FROM SERPENTINITE

摘要

Preparation of magnesium from multimillion ton asbestos production dumps, i.e., serpentinite, provides its competitiveness in the world and internal markets due to the low raw material costs, whose price in the net cost of finished metal reaches 30%. Artificial carnallite for magnesium electrolysis is separated by crystallization in multistage vacuum-crystallization units from a solution formed as a result of synthesizing magnesium chloride solution and added potassium chloride. Chromium-magnesium solution forms on leaching serpentinite with hydrochloric acid and separation of impurities, but potassium chloride from the electrolysis bath after dissolution and crystallization is returned again to the technology. Crystallization units for carnallite and potassium chloride are fitted with self-evaporation crystallizers of SverdNIIkhimmash construction, which are used successfully in the production of many inorganic salts.