以钛磁铁矿、煤粉和氧化钙为原料，研究了矿粉粒度、加水量以及制球压力对球团落下强度、抗压强度的影响，确定了最佳制球条件。根据铁矿石的直接还原和熔分原理，研究了热量和金属化率对含碳球团熔分的影响。900℃以下，球团金属化率极低，只有热量对熔分产生影响；1000℃以上，球团金属化率较高，热量和金属化率共同对熔分产生影响。钛磁铁矿含碳球团的最佳制球条件为：粒度0．075～0．106 mm，加入水量8％，制球压力4 MPa。通过对预还原1000～1300℃的球团进行熔分试验分析发现，随预还原温度升高，球团金属化率提高，熔分时间变短。%With titanomagnetite, pulverized coal and CaO as raw materials for pelletizing, effects of particle size, water addition and pelletizing pressure on the falling strength and compressive strength were explored through experiments, resulting in the optimized pelletizing conditions. The influence of heat and metallization rate on the metal⁃slag separation of carbon⁃containing pellets was investigated based on the theories of direct reduction and melting separation for iron ore. It is found that low metallization rate appears at the temperature less than 900 ℃, with melting separation just affected by the heat. However, a high metallization rate will appear at the temperature over 1 000 ℃, with the heat and metallization rate brought a joint effect on the melting separation. Thus, the optimized pelletizing conditions were obtained for the titanomagnetite, including the particle size of 0.075~0.106 mm, water addition of 8%, and pelletizing pressure at 4 MPa. The following melting separation experiment with pellets subjected to the pre⁃reduction at 1 000~1 300 ℃ indicated that an increase in the pre⁃reduction temperature could not only increase metallization rate, but also shorten melting separation time.
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