THERMAL-DECOMPOSITION OF DOLOMITE AND THE EXTRACTION OF ITS CONSTITUENTS

Several analytical techniques were used to identify and optimize the m ain variables affecting the separation of magnesium and calcium carbon ates from dolomite using partial thermal decomposition followed by hyd ration and recarbonation processes, It is shown that by careful contro l of these variables, the MgO content in the calcium carbonate residue can be reduced to less than 3.3% in a single processing cycle, result ing in a suitable raw material for the production of portland cement, High purity hydromagnesite, having less than 1% total impurities, was obtained from the aqueous residue. (C) 1997 Published by Elsevier Scie nce Ltd.