Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets
Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets
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DOI：
10.1007/s42243-023-01066-5
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发表时间：
2023-09
影响因子：
2.5
通讯作者：
Jian Pan;Chenmei Tang;Cong-cong Yang;De‐qing Zhu;Zheng-qi Guo;Wei-qun Huang
中科院分区：
文献类型：
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作者：
Jian Pan;Chenmei Tang;Cong-cong Yang;De‐qing Zhu;Zheng-qi Guo;Wei-qun Huang
在相同的Al 2 O3含量为2 wt.%时，研究了氧化铝赋存形态对赤铁矿球团和磁铁矿球团冶金性能的影响，包括还原指数（RI）、低温还原崩解指数（RDI）、还原溶胀指数（RSI）和高温软化滴落性能。通过对烧结球团矿的矿物学研究，揭示了氧化铝赋存状态对球团矿物相组成和显微结构的影响。结果表明，氧化铝的赋存状态对磁铁矿球团和赤铁矿球团的冶金性能均有较大影响。添加所有氧化铝的存在形式有助于降低球团的还原性，特别是在三水铝石的磁铁矿球团的RI为58.4%和高岭石的赤铁矿球团的RI为56.8%。然而，添加所有氧化铝的存在形式提高了磁铁矿球团的RDI，而各种氧化铝的存在形式之间没有显着差异。氧化铝的赋存形态对赤铁矿球团矿的RDI影响不大。游离氧化铝、三水铝石和高岭石的存在往往会提高赤铁矿和磁铁矿球团的RSI，而铁铝尖晶石则呈现相反的趋势，RSI为25.6%。对于磁铁矿球团的软熔滴落性能，氧化铝的各种赋存形态都有助于磁铁矿球团软熔区间的缩小。同时，氧化铝、三水铝石和高岭石分别在229、217和88 °C下给出较窄的软化-滴落间隔，而铁铝尖晶石的添加由于其高熔点而在276 °C下导致最大的熔融范围。关于赤铁矿球团，游离氧化铝、三水铝石和铁铝尖晶石倾向于扩大熔融范围，而高岭石由于在高温下形成更大量的渣相而有助于降低1148 °C的滴落温度和88 °C的窄软化-滴落间隔。
The effect of alumina occurrence form on the metallurgical properties of both hematite and magnetite pellets was investigated at the same Al2O3level of 2 wt.%, including reduction index (RI), low-temperature reduction disintegration index (RDI), reduction swelling index (RSI), and high-temperature softening–dripping performance. The mineralogy of fired pellets was also studied to reveal the influence of alumina occurrence form on the phase composition and microstructure. From the results, the alumina occurrence form presents tremendous impacts on the metallurgical performance of both magnetite and hematite pellets. Addition of all alumina occurrence forms contributes to inferior reducibility of pellets, especially in the case of gibbsite for magnetite pellets with a RI of 58.4% and kaolinite for hematite pellets with a RI of 56.8%. However, addition of all alumina occurrence forms improves the RDI of magnetite pellets, while there is no significant difference among various alumina occurrence forms. In contrast, alumina occurrence forms have little influence on the RDI of hematite pellets. The presence of free alumina, gibbsite, and kaolinite tends to improve the RSI of hematite and magnetite pellets, whereas hercynite gives the opposite trend with a RSI of 25.6%. For softening–dripping performance of magnetite pellets, all alumina occurrence forms contribute to narrower softening–melting interval. Meanwhile, alumina, gibbsite, and kaolinite give narrower softening–dripping interval, at 229, 217, and 88 °C, respectively, whereas addition of hercynite results in the largest melting range at 276 °C due to its high melting point. Regarding hematite pellets, free alumina, gibbsite, and hercynite tend to enlarge melting range, whereas kaolinite contributes to lower dripping temperature of 1148 °C and narrow softening–dripping interval of 88 °C due to the formation of a greater amount of slag phase at high temperatures.