焙烧预还原工艺对氧化镍还原效果的影响

Influence of Roasting Pre-Reduction Process on Reduction Effect of Nickel Oxide

本文对氧化镍干燥和焙烧预还原工艺进行了研究,通过研究回转窑干燥工艺的进料速度、窑体旋转速度和干燥温度,确定在240℃下可将含水37%的红土镍矿干燥至含水18%~22%;通过研究焙烧温度,确定在465℃下,可将干燥工序产出的含水18%~22%的干矿干燥至含水0.5%~0.7%;通过研究预还原工艺的温度和还原剂率,确定在还原温度1100℃、还原剂率6%的条件下,可实现Ni°/Ni总≥15%的预还原效果。同时本文指出,在红土镍矿焙烧预还原工序,烟气中含尘量较大,生产中应注意焙烧预还原工序烟尘的收集。

This paper studies drying and roasting pre-reduction process of nickel oxide.By studying the feed speed,rotary speed and drying temperature of the rotary kiln drying process,it is determined that laterite nickel ore with 37%water content can be dried to 18%~22%water content at 240℃;By studying the roasting temperature,dry ore with 18%~22%water content can be dried to 0.5%~0.7%water content at 465℃;By studying the temperature and reductant rate of the pre-reduction process,it is de-termined that Ni°/Ni(≥15%)can be achieved under the conditions of reduction temperature at 1100℃and reductant rate at 6%.At the same time,this paper points out that the dust content of flue gas is large in the pre-reduction process of laterite nickel ore roasting,and attention should be paid to the collection of dust in this process.