冀东磁铁精矿球团焙烧机理的研究

Study on roasting mechanism of pellet made from Jidong magnetite concentrates

研究了焙烧温度、时间等因素对冀东磁铁精矿粉球团焙烧质量的影响。当预热温度超过1000℃时，颗粒表面生成液相，造成球团氧化不完全；当焙烧温度超过1275℃时，球团中的脉石大量同化，产生大量硅酸盐液相，降低成品球强度。冀东磁铁精矿球团最佳焙烧工艺为：氧化温度为900～950℃，氧化时间不低于20min，焙烧温度为1250～1275℃，焙烧时间不低于20min。

The effects of roasting time and temperature on the roasting quality of pellet made from Jidong magnetite concentrates are studied in the paper. When the oxidizing temperature is higher than 1 000℃, liquid phase will be formed in the face of grain, so the pellet oxidation is incomplete. When the roasting temperature is higher than 1 275 ℃, the assimilation of gangue minerals will take place and a great amount of silicate liquid phase can be observed, resulting in low strength of the pellet. The optimal technological parameters of the pellet can be summarized as follows： the oxidizing temperature is between 900℃ to 950 ℃, the oxidizing time should be over 20 min; the optimal roasting temperature is between 1 250 ℃ to 1 275℃ and the roasting time should be over 20 minute.