褐铁矿的煤泥球团直接还原

Direct Reduction of Limonite?Coal Slime Pellets

以煤泥为还原剂,考察了其种类及用量、还原温度与时间以及CaCO_3添加量等对褐铁矿中铁氧化物直接还原的影响,研究了不同条件下还原产物中铁矿物的存在形式,考察了添加剂用量对含碳球团熔融分解的影响.结果表明,煤泥C还原效果最好,其用量30%,CaCO_3添加量3%,在1250℃下直接还原30 min,含碳球团金属化率达94.02%.铁在产物中主要以金属铁颗粒存在,粒度多大于30mm,添加3%CaCO_3使渣铁分离效果明显,有利于产物分离.表明煤泥是一种良好的褐铁矿还原剂.

The effects of type and dosage of coal slime as reducing agent, reduction temperature and time, and dosage of CaCO3 on direct reduction of limonite containing iron oxides were examined. The iron-containing components in reduced product at different conditions were analyzed. The effect of additive dosage on carbon-containing pellet melt decomposition was also studied. The results show that coal slime C is the best reducing agent. The reduced product with metallization rate of 94.02% is obtained under the conditions of coal slime C 30%, CaCO3 3%, and 1 250 ℃ for 30 min. The iron in product is basically metallic iron with the particle sizes over 30 mm. Moreover, addition of 3% CaCO3 makes slag and iron separate apparently, which is conducive to further separation of reduced product. Therefore, the coal slime can be regarded as a good reducing agent for direct reduction of limonite.