Abstract: During the preparation process of the raw material in magnesium production with silicothermic method， about 5% fines are lost in the dolomite calcination process. In order to solve this problem， a new technology was proposed that dolomite is made into pellets first， and then calcined to prepare pellets with high reactivity and stability. The burning loss of dolomite， the ignition loss of the calcined dolomite and the hydration activity of pellets were investigated after calcination. The results indicated that calcined dolomite with good properties can be prepared via direct briquetting technology， and the calcination time is shortened effectively. When calcination time reaches 1h， the burning loss of briquetted dolomite can reach 45%， the ignition loss of calcined dolomite can reach 189%， the hydration activity can reach 35%. The moisture absorption of pellets in this process is much less than that in conventional calcination process.

Key words: dolomite, briquetting, burning loss, ignition loss, hydration activity