Preparation Of Magnesium Oxide With The Light Burned Dolomite

This paper uses the Wulongquan mine of light burned dolomite powder prepared Magnesium Oxide by carbonation method, Study of dolomitic lime digestive, The carbonation of dolomite lime digestion, Pyrolysis of magnesium bicarbonate solution and the calcination of pyrolysis products. Optimization of process conditions for the reaction process, thus the optimal technological conditions of the preparation of the Magnesium Oxide.The optimum conditions of dolomitic lime digestive:digestion of temperature was 95℃, digestion of time was 60min, material:water was 3:5, the raw material particle size as small as possible and the aging time was 18h, the dolomite lime weight gain rate was 17.69%. The optimum conditions for carbonation:the digestive dolomitic lime carbonate concentration was 30g·L-1, carbonate temperature was 15℃, CO2 gas flow was 60L·h-1 and carbonated end pH was 7.26, the percentage of magnesium into the liquid phase is 80.46%, calcium into the liquid phase is 0.0644g·L-1. Carbonated end pH 7.26 is the lowest carbonated end pH guaranteed to Magnesium Oxide purity of prepared in more than 98%.Magnesium bicarbonate solution pyrolysis temperature was 95℃, the pyrolysis rate was 96.15%, the pyrolysis products were basic magnesium carbonate. Through to bubbling the magnesium bicarbonate solution, reduce the magnesium bicarbonate solution pyrolysis temperature, adding crystal seeds promote the decomposition of magnesium bicarbonate solution, to prepare nesquehonite. Calcined nesquehonite, and prepared the high purity Magnesium Oxide, the content of MgO is 99.91%, CaO is 0.09%.Added to the nesquehonite in Magnesium bicarbonate solution, bubbling, pyrolysis under the temperature of 90℃, prepared long column type basic magnesium carbonate was composed of layers; calcined and prepared long column type Magnesium Oxide consisting of layers; Use soluble starch as dispersant prepared the hemispherical Magnesium Oxide.