This paper studies mineralogical phase transformations of Indonesia nickel laterite ores during roasting. The influence of pre-roasting temperature on the degree of gas(V (CO) : V (O2)=50 : 50)reduction is also investigated. Different factors affecting reduction of the laterite ores are tested and analyzed with various means such as differential scanning calorimeter thermal gravimetric (DSC/TG), Brunauer Emmett Teller (BET) specific surface area analysis, X-ray diffraction (XRD) and scanning electron microscope (SEM).The results show that, during the roasting process, goethite is dehydrolyzed at about 300°C. It is then transformed to hematite and serpentine decomposes around 600~700°C leading to formulation of olivine if agglomerating is at higher temperature. Nickel and iron metallization rate increases with the increasing pre-roasting temperature by using gas mixture (V (CO) : V (O2)=50 : 50). The highest reduction rate can reach 86.81% with the sample being roasted at 700°C. If the calcination temperature exceeds the olivine formation temperature, the nickel metallization rate declines to 66.73%.
XU Yu-Ling, GUO Shu-Jiang, BIAN Yu-Xiang, CHEN Song, DING Wei-Zhong, TAN Ding-Sheng
. Effect of Pre-roasting on Mineral Phase Transformations and Gas Reduction of Nickel Laterite Ores[J]. Journal of Shanghai University, 2014
, 20(6)
: 697
-700
.
DOI: 10.3969/j.issn.1007-2861.2014.01.025
[1] 毛麒瑞. 战略储备金属: 镍[J]. 中国物资再生, 1999(10): 36-37.
[2] Ashok D D, Gordon W, Robert C O. The past and the future of nickel laterites [C]// PDAC
2004 International Convention, Trade Show & Investors Exchange. 2004: 7-10.
[3] Warner A E M, Diaz C M, Dalvi A D, et al. JOM world nonferrous smelter survey, part Ⅲ:
nickel: laterite [J]. Journal of the Minerals, Metals and Materials Society, 2006, 58(4): 11-20.
[4] 周晓文, 张建春, 罗仙平. 从红土镍矿中提取镍的技术研究现状及展望[J]. 四川有色金属, 2008(1):
18-22.
[5] 栾心汉, 唐琳, 李小明. 镍铁冶金技术及设备[M]. 2版. 北京: 冶金工业出版社, 2011: 2-3.
[6] Brand N W, Butt C R M, Elias M. Nickel laterites: classification and features [J]. AGSO J
Aust Geol Geophys, 1998, 17: 81-88.
[7] Power L F, Geiger G H. The application of the reduction roast ammoniacal ammonium
carbonate leach to nickel laterites [J]. Minerals Science, 1997, 9(1): 32-50.
[8] Whittington B, Johnson J, Quan L. Pressure acid leaching of Bulong nickel laterite ore:
partⅡ. Effect of ore type [J]. Hydrometallurgy, 2003, 70: 47-62.
[9] Mihaylov I, Krause E, Colton D F, et al. The development of a novel hydrometallurgical
process for nickel and cobalt recovery from Goro laterite ore [J]. CIM Bulletin, 2000, 93: 124-130.
[10] 庞建明, 郭培民, 赵沛. 火法冶炼红土镍矿技术分析[J]. 钢铁研究学报, 2011, 23(6): 1-4.
[11] Utigard T, Bergman R A. Gaseous reduction of laterite ores [J]. Metallurgical Transactions
B, 1992, 23: 271-275.
[12] Kawahara M, Toguri J M, Bergman R A. Reducibility of laterite ores [J]. Metallugical
Transactions B, 1988, 19: 181-186.
[13] Robin H L, Mark A S, Kendra V S, et al. Passive mixing in a three-dimensional serpentine
microchannel [J]. Journal of Microelectromechanical Systems, 2000, 6(9): 190-197.
[14] Valix M, Cheung W H. Study of phase transformation of laterite ores at high temperature
[J]. Minerals Engineering, 2002, 15: 607-612.
[15] Jungah K, Gjergj D, Hideaki T, et al. Calcination of low-grade laterite for concentration of
Ni by magnetic separation [J]. Minerals Engineering, 2010, 23: 282-288.
[16] Lopez F A L, Ramirez M C R, Pons J A, et al. Kinetic study of the thermal decomposition
of low-grade nickeliferous laterite ores [J]. J Therm Anal Calorim, 2008, 94: 517-522.
[17] Emmanuel N Z, Charalabos Z, Theodora P, et al. Phase transformations of nickliferous
laterites during preheating and reduction with carbon monoxide [J]. J Therm Anal Calorim,
2010, 100: 133-139.
[18] Hayashi M. Effect of phase transition on reductive roasting of nickel bearing serpentine [D].
The Utah: University of Utah, 1961.