SLURRY FILTRATION AND CAKE WASHING AFTER THE HCL-LEACH OF MAGNESITE AND SERPENTINE - CONTINUOUS WASHING MODEL

Four different ores of magnesite and serpentine were leached with hydrochloric acid to produce concentrated magnesium chloride liquors. The neutralized slurries were filtered at a constant pressure, and the cakes were washed with water. As for filtration, the mass balance was calculated based on magnesium analyses, while the Darcy-Ruth equation was used to investigate the kinetics and assess the specific resistance of cakes. As for washing, the mass balance and kinetics were accounted for in terms of a continuous mathematical model, which is compatible with the Moncrieff equation. This new model explains well the washing test results. Washing operations can be optimized only in economical terms, and a complete set of mathematical formulae was presented for the optimization procedure.