不同块矿配比条件下的高炉炉料结构

BLAST FURNACE BURDEN STRUCTURE UNDER DIFFERENT BLOCK ORE RATIOS

为实现高炉的经济、高产和高质,邢台某钢铁企业采用了富氧大喷吹的工艺措施。围绕高炉现场的原燃料条件,在低烧结矿比的条件下,研究了调整不同块矿及球团矿等酸性炉料的入炉量对降低软熔带位置、改善料柱的透气性、提高高炉的透气性指数和煤气利用率的影响。研究结果表明:当炉料结构为烧结矿+球团矿+南非矿时,随着南非块比例的增加,软熔带的位置上移,滴落温度升高,最大压差和特征值升高,料柱透气性变差,另外南非块碱金属较高,易损坏焦炭结构,故南非块长期使用时,配加比例不宜超过8%;在烧结矿和球团矿入炉比例一定的情况下,逐渐使用纽曼块、SP10替代南非块,当南非块与纽曼块比例为1∶1时,最大压差和特征值最低,料柱透气性最佳为868 kPa·℃,即南非块和纽曼块均为10%较适宜;随着SP10矿替代比例的增加,软熔带区间变宽,且最大压差和特征值都明显升高,炉料的熔滴性能恶化;由于SP10爆裂性能较差,易导致粉末产生量较多,进一步造成料柱透气性恶化,因此SP10不易超过6%。

In order to achieve economic,high production,and high quality of blast furnaces,a steel enterprise in Xingtai has adopted the process measure of enriched oxygen and large injection.Based on the raw material and fuel conditions at the blast furnace site,the effects of adjusting the amount of acidic furnace materials such as lump ore and pellet ore on reducing the position of the soft melt zone,improving the permeability of the material column,increasing the permeability index and gas utilization rate of the blast furnace were studied under the condition of low sintering ore ratio.The research results show that when the structure of the furnace material is sintered ore+pellet ore+South African ore,as the proportion of South African blocks increases,the position of the soft melt zone moves upward,the drop temperature increases,the maximum pressure difference and characteristic value increase,and the permeability of the material column decreases.In addition,South African blocks have higher alkali metals,which are prone to damage the coke structure.Therefore,when South African blocks are used for a long time,the addition ratio should not exceed 8%.When the ratio of sintered ore and pellet ore to the furnace is constant,Newman block and SP10 are gradually used to replace South African block.When the ratio of South African block to Newman block is 1∶1,the maximum pressure difference and characteristic value are the lowest,and the best permeability of the material column is 868 kPa℃,which is suitable for both South African block and Newman block to be 10%.As the replacement ratio of SP10 ore increases,the range of soft melt zone becomes wider,and the maximum pressure difference and characteristic value both significantly increase,leading to a deterioration of the droplet performance of the furnace material.Due to the poor burst performance of SP10,it is easy to produce a large amount of powder,which further leads to a deterioration of the permeability of the material column.Therefore,SP10 is not easy to exceed 6%.