摘要
以硫代硫酸钠作为添加剂,用于红土镍矿还原焙烧-磁选工艺。研究发现,该添加剂兼具碱金属盐及硫化剂的作用。在焙烧过程中,硫代硫酸钠中的碱金属离子将硅酸盐相中的镍离子置换出来;硫代硫酸钠中的S在还原阶段与铁氧化物高温下生成Fe-Ni-S相,并以液态的形式实现对镍铁的富集,而没有磁性的FeS在后续的磁选分离中得以抛除,又实现对镍的分选。对还原焙烧及磁选工艺条件进行了考察,结果表明:还原温度为1 100℃,还原时间60min,还原气CO与CO2体积比为8/2,添加剂质量分数20%,磁场强度0.15T,磨矿时间1.0min时,精矿镍品位及回收率分别从最初的2.58%、41.66%增加至7.62%、64.83%,而镍铁回收率差可达47.10%,达到了镍的富集及分选的目的。
The experiment chooses sodium thiosulfate as an additive in the process of the reduction roasting-magnetic separation for nickel laterite ore.The study finds that the additive plays the role of both alkali metal salt and sulfuration.In the process of roasting,the alkali metal ion replaces nickel ion in silicate phase,and the sulfur forms Fe-Ni-S phase with iron oxide in reduction stage at high temperature.The enrichment of ferronickel in the form of liquid and the formation of no magnetic FeS,which is abandoned easily in the subsequent magnetic separation,make the separation of nickel achievable.In this paper,the conditions of reduction roasting and magnetic separation technology were also investigated.The experimental results show that the content and recovery of nickel increase to 7.62% and 64.83% from the original 2.58% and41.66%,respectively,under the best condition of reduction temperature 1 100℃,reduction time60 min,the ratio of reducing gas volume V（CO）/V（CO2）8/2,the mass fraction of additive20%,the intensity of magnetic field 0.15 T,and grinding time 1.0min.The result of nickel-iron recovery difference of 47.10% arrive the goal of the nickel enrichment and separation for nickel laterite ore.
出处
《太原理工大学学报》
CAS
北大核心
2016年第2期144-149,共6页
Journal of Taiyuan University of Technology
基金
国家自然科学基金资助项目(21276172)
关键词
红土镍矿
硫代硫酸钠
还原焙烧
分选
laterite nickel ore
sodium thiosulfate
reduction roasting
separation
