A new roasting process with a conveying bed was constructed and used to remove sulfur of high-sulfur bauxite. Roasting temperature, phase transformation, microcrystal, specific surface area of high-sulfur bauxite, and the mechanism of the reaction during the roasting process were analyzed. The digestion properties of roasted bauxite were also investigated. The results showed that the sulfur in high-sulfur bauxite can be efficiently removed by roasting in the conveying bed at 520‒720 °C for 2 s. Major reactions of high-sulfur bauxite during roasting were the dehydration of minerals, desulfurization of pyrite, sulfation of SO2, and decomposition of sulfate. The rate of mineral dehydration reaction was significantly slower than that of the desulfurization reaction. The specific surface area of roasted ore greatly increased, and the microcrystal of Al-O mineral was refined, which was conducive to Al2O3 digestion. The mass fraction of sulfide sulfur in high-sulfur bauxite was reduced from 1.20% to 0.01%, and the relative digestibility of alumina reached more than 99% when roasting at 600 °C for 2 s. This paper provides revelations and instructions for the process development and application of high-sulfur bauxite.
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机译：建造具有输送床的新型焙烧过程，并用于去除高硫铝土矿的硫。分析了烘焙温度，相变，微晶，高硫铝土矿的比表面积，以及在焙烧过程中的反应机理。还研究了烤铝土矿的消化性质。结果表明，在520-720℃下通过在输送床中焙烧2 s，可以有效地除去高硫铝土矿中的硫。高硫铝土矿在烘焙过程中的主要反应是矿物质的脱水，黄铁矿脱硫，SO 2的硫化和硫酸盐的分解。矿物脱水反应的速率明显慢于脱硫反应的速度。焙烧矿石的比表面积大大增加，并精制了Al-O矿物的微晶，这有利于Al 2 O 3消化。高硫铝土矿中硫化硫的质量分数从1.20％降低至0.01％，并且当在600℃下烘烤2 s时，氧化铝的相对消化率达到了99％以上。本文提供了高硫铝土矿工艺开发和应用的启示和说明。
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