针对首钢京唐504m2带式焙烧机生产的球团矿抗压强度高,而还原性差的问题,通过研究不同焙烧温度下球团矿的抗压强度、还原度、还原膨胀率及其显微结构的变化,得出以下结论:随着焙烧温度从1200℃提高到1280℃,磁铁矿球团的抗压强度提高,而还原度明显降低,焙烧温度为1230℃时,球团还原膨胀率最低。综合考虑,应在满足抗压强度的前提下,尽量降低焙烧温度,以改善球团矿的冶金性能。根据试验结果对带式机焙烧温度进行调整后,球团矿抗压强度控制在3000N/P左右,还原度提高到67.78%,还原膨胀率也控制在18%以下,取得了显著效果。
In view of high compressive strength but poor reducibility of pellets produced with Shougang 504 m2 travelling grate indurating machine, through studying the difference of compressive strength, reducibility, swelling index and microstructure of the pellets under different firing temperature, the following conclusions are obtained:the compressive strength of magnetite pellets increases with the calcination temperature increasing from 1 200 ℃ to 1 280 ℃, but the reduction degree of pellets significantly reduces, and the reduction swelling index of pellets is the lowest when the roasting temperature is 1 230 ~C. Considering comprehensively, we must reduce the firing temperature as far as possible to improve the metallurgical performance of pellets under the prerequisite of meeting the conditions of compressive strength. After adjustment of firing temperature of the travelling grate indurating machine in accordance with the test results, the compressive strength of pellets is controlled around 3 000 N/P,the reduction degree is increased to 67.78% , the reduction swelling index is also controlled below 18%, and remarkable effect is obtained.