The process of one-step reduction roasting and magnetic separation was adopted to prepare ferro-nickel alloy from low-grade nickel laterite ore (w(Ni)=1.52%, w(Fe)=14.08%). The roasting factors including roasting temperature, time, reducing coal amount and compound additive were investigated. The results indicate that under the conditions of adding 20% reducing coal, 12% compound additive, roasting temperature and roasting in a N2 protected atmosphere 180 min at 1 200℃, most of nickel and a spot of iron are selectively reduced. Then conventional magnetic separation is carried out after water quenching of the roasted ore. The content of Ni and the ratio of Fe/Ni are 10.74% and 4.5 in ferro-nickel concentrate prepared by this method, respectively. And the recovery rate of Ni is 86.23%, which indicates that a high recovery of ferro-nickel from nickel laterite ore is achieved indeed.%以低品位红土镍矿(w(Ni)=1.52％,w(Fe)=14.08％)为原料,采用“一步还原焙烧-磁选”工艺制取镍铁合金.考察反应温度、反应时间、还原煤量和复合添加剂对红土镍矿焙烧效果的影响.研究结果表明:在还原煤为20％、复合添加剂为12％、焙烧温度为1 200℃、通N2保护条件下焙烧180 min,原矿中的大部分氧化镍和少量氧化铁得到选择性还原;焙砂水淬急冷后常规磁选,得到Ni质量分数为10.74％,Fe与Ni的质量分数之比为4.5,Ni回收率为86.23％的镍铁精矿,达到从红土镍矿中高效回收镍铁的目的.
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