氯化钠对低品位红土矿煤基还原富集镍铁作用的研究  

Sodium Chloride on Reduction and Enrichment of Ferronickel in Low-grade Laterite Ore with Coal

作　　者：郭祥 王慧瑶 曲国瑞 周世伟[2,3] 李博[1,2,3] 魏永刚 Guo Xiang;Wang Huiyao;Qu Guorui;Zhou Shiwei;Li Bo;Wei Yonggang(State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming 650093,China;Faculty of Metallurgy and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China;Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction of Ministry of Education,Kunming 650093,China)

机构地区：[1]省部共建复杂有色金属资源清洁利用国家重点实验室,云南昆明650093 [2]昆明理工大学冶金与能源工程学院,云南昆明650093 [3]冶金节能减排教育部工程研究中心,云南昆明650093

出　　处：《稀有金属》2020年第10期1085-1093,共9页Chinese Journal of Rare Metals

基　　金：云南省重点研发计划—国际科技合作专项项目(2018IA055);国家自然科学基金项目(U1302274)资助。

摘　　要：采用选择性直接还原焙烧-磁选工艺,对含镍1.29%、铁43.19%的印尼低品位褐铁型红土镍矿进行了煤基还原富集镍铁研究。在对还原过程热力学分析的基础上,利用X射线衍射(XRD)和电子探针显微(EPMA)分析等表征方法研究了氯化钠添加剂作用下镍铁还原富集规律。探讨了还原温度、焙烧时间、还原剂及添加剂加入量等参数对镍铁富集和回收效果的影响。结果表明,分布于蛇纹石中的镍氧化物和原矿中铁氧化物得到了选择性还原,在还原温度1250℃、焙烧时间80 min、还原剂无烟煤10%、添加剂NaCl 5%的最佳实验条件下,获得镍、铁品位分别为8.44%和59.99%的精矿,镍回收率79.17%,Ni/Fe(质量比)由原矿的0.03提高至0.14。同时,研究表明还原过程氯化钠添加剂可以促进镍铁颗粒的聚集长大,有利于提高磁选精矿中镍品位,实现低镍高铁红土矿中镍的有效富集。A selective direct reduction roasting-magnetic separation process was carried out to study the coal-based reduction and enrichment of ferronickel on Indonesian low-grade brown iron type laterite nickel ore with 1.29% nickel and 43.19% iron.Based on the thermodynamic analysis of the reduction process,the characterization of nickel-iron reduction and enrichment under the action of sodium chloride was researched by means of X-ray diffraction(XRD)and electron probe micro-analyzer(EPMA).The reduction temperature,roasting time,reducing agent and additive addition on the enrichment and recovery of ferronickel were discussed.The results showed that the nickel oxides distributed in serpentine and the iron oxides in ore were selectively reduced,under the optimal experimental conditions of reduction temperature 1250 ℃,roasting time 80 min,reducing agent anthracite 10%,additive NaCl 5%,the concentrates with nickel and iron grades of 8.44% and 59.99% were obtained respectively,while nickel recovery rate was 79.17% and the Ni/Fe(mass ratio)increased from 0.03 in raw ore to 0.14 now.And the study showed that the sodium chloride additive in the reduction process could promote the aggregation and growth of ferronickel particles,which was beneficial to increase the nickel grade in the magnetic separation concentrates and achieved the effective enrichment of nickel in low-nickel high-iron laterite ore.

关 键 词：红土镍矿 还原焙烧-磁选 镍铁 氯化钠 品位 

分 类 号：TF815[冶金工程—有色金属冶金]