塞拉利昂高铝矿对烧结矿性能的影响

Effects of high alumina Sierra Leone ores on sinter performance

针对塞拉利昂高铝矿生产的烧结矿易引起高炉炼铁渣比和焦比升高,且该矿用于烧结生产易使料层透气性下降等问题,通过在固定配比的地方精粉、PB粉及南非精粉条件下,采用塞拉利昂高铝矿代替部分澳粗56进行混合配料,并通过提高高硅朝鲜粗粉配比以稳定烧结矿SiO2质量分数在5.6%,进行烧结杯试验,探究配加不同质量分数的塞拉利昂高铝矿对烧结矿品位、成品率、转鼓强度及还原性的影响,并使用偏光显微镜及X射线衍射仪对烧结矿进行了显微检测分析。结果表明:塞拉利昂高铝矿的逐步增加,促使烧结矿品位、成品率、转鼓强度及烧结时间均有所降低;利用系数稳步提高;成品烧结矿<5 mm粒度占比降低;还原粉化指数及还原度指数波动较大。综合考虑,配加质量分数19.2%的塞拉利昂高铝矿可使烧结矿质量达到最优。

In view of such problems as the increase of slag ratio and coke ratio during BF operation with sinter produced by adding from high alumina Sierra Leone ores and a decrease in permeability of sinter bed,under the condition of fixed ratio of local concentrate fines,PB powder and South African concentrate fines,by adopting high alumina Sierra Leone ores to replace part of Australian crude ores 56 for mixed proportioning,and by increasing high-silica North Korean crude powder to stabilize the sinter SiO2 content at 5.6%,the sintering pot experiment is carried out to explore the effects of different ratio of high alumina Sierra Leone ores on sinter grade,product yield,tumbler strength and reducibility,the polarizing microscope and X-ray diffractometer are used for microscopic testing and analysis of sinter.The results show that,with the gradual increase of high alumina Sierra Leone ores,the sinter grade,the product yield,the sinter tumbler strength and sintering time all somewhat reduces;the utilization factor increases steadily;the amount of <5 mm product sinter is less;the reduction degradation index and reduction degree fluctuate greatly.Considering the quality of the sinter,it is optimum when 19.2% high alumina Sierra Leone ores are added.