Pilot scale test of producing nickel concentrate from low-grade saprolitic laterite by direct reduction-magnetic separation  

作　　者：郑国林 朱德庆 潘建 李启厚 安月明 朱景和 刘志宏 

机构地区：[1]School of Minerals Processing and Bioengineering,Central South University [2]School of Metallurgical Science and Engineering,Central South University [3]China Nonferrous Metal Mining(Group),Co.,Ltd

出　　处：《Journal of Central South University》2014年第5期1771-1777,共7页中南大学学报（英文版）

基　　金：Project(NDRC-Hitech Office 2009-606)supported by the National Development and Reform Commission of China;Project(50974135)supported by the National Natural Science Foundation of China

摘　　要：The enrichment of Ni from a low-grade saprolitic laterite ore,which has been pre-treated by high pressure grinding roller（HPGR） to be 74% passing 0.074 mm and contains 0.92% Ni,18.47% Fe,10.61% MgO and 42.27% SiO2,was conducted by using pelletizing,rotary kiln reduction and magnetic separation process on a semi industrial scale,and the effects of reduction duration,mass ratio of coal to pellets（C/P）,the types of magnetic separator,the sections of grinding-separation and the grinding fineness on the recovery of Ni and Fe were examined.It is shown that nickel concentrate containing 3.13 % Ni and 59.20 % Fe was achieved at recoveries of 84.36 % and 71.51% for Ni and Fe,respectively under the following conditions：reducing at （1120±40） ℃ for 120 min,C/P being 1.0,wet grinding of reduced pellets up to 70%-87% passing 0.074 mm and a magnetic field intensity of 238.8 kA/m during the first section of grinding-magnetic separation,and a grinding fineness of 84%-91% passing 0.045 mm and a magnetic intensity of 39.8 kA/m during the second section of grinding-magnetic separation.The enriched Ni containing concentrate has a low content of S and P,and can be used for further processing to produce high-grade ferronickel alloy.The enrichment of Ni from a low-grade saprolitic laterite ore,which has been pre-treated by high pressure grinding roller(HPGR)to be 74% passing 0.074 mm and contains 0.92% Ni,18.47% Fe,10.61% MgO and 42.27% SiO2,was conducted by using pelletizing,rotary kiln reduction and magnetic separation process on a semi industrial scale,and the effects of reduction duration,mass ratio of coal to pellets(C/P),the types of magnetic separator,the sections of grinding-separation and the grinding fineness on the recovery of Ni and Fe were examined.It is shown that nickel concentrate containing 3.13 % Ni and 59.20 % Fe was achieved at recoveries of 84.36 % and 71.51 % for Ni and Fe,respectively under the following conditions: reducing at(1120±40)°C for 120 min,C/P being 1.0,wet grinding of reduced pellets up to 70%-87% passing 0.074 mm and a magnetic field intensity of 238.8 kA/m during the first section of grinding-magnetic separation,and a grinding fineness of 84%-91% passing 0.045 mm and a magnetic intensity of 39.8 kA/m during the second section of grinding-magnetic separation.The enriched Ni containing concentrate has a low content of S and P,and can be used for further processing to produce high-grade ferronickel alloy.

关 键 词：low-grade saprolitic laterite direct reduction magnetic separation PELLETIZATION segmented grinding nickel concentrate 

分 类 号：TD954[矿业工程—选矿] TF55[冶金工程—钢铁冶金]