Abstract Blast furnace (BF) dust is a typical fine-grained solid waste generated as by-product during the ironmaking process. A novel in-flight reduction technology has been developed to recovery the fine iron-bearing dusts efficiently and cleanly to bypass the sintering/pelletization steps. In this work, the reduction behavior of BF dust particle during in-flight process in H2-rich and CO atmosphere were investigated comparatively. A maximum reduction degree of 93.4% is obtained in H2-rich atmosphere at temperature of 1573 K within 1.6 s of reduction time. Morphological observations reveal that dust particles reduced in H2-rich atmosphere is more coarse and porous than in CO. The carbon contained in dust is confirmed to participate in the reduction process in the form of gasification. The heat and mass transfer characteristics between dust particle and reducing gas during in-flight process are also analyzed, which provide fundamental knowledge for effective utilization of BF dust with in-flight reduction technology.

中文翻译：

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富氢和一氧化碳气氛中高炉粉尘颗粒在飞行过程中的还原行为对比研究

摘要 高炉粉尘是一种典型的细粒固体废物，是炼铁过程中的副产品。已开发出一种新颖的飞行中还原技术，可高效、干净地回收含铁细粉，绕过烧结/球团步骤。在这项工作中，比较研究了在富 H2 和 CO 气氛中飞行过程中 BF 粉尘颗粒的还原行为。在 1.6 s 的还原时间内，在 1573 K 的温度下，在富含 H2 的气氛中获得了 93.4% 的最大还原度。形态学观察表明，在富含 H2 的大气中还原的尘埃颗粒比 CO 中的更粗和多孔。尘埃中的碳被证实以气化的形式参与还原过程。