学术论文

      煤种对红土镍矿中镍选择性还原的影响机理

      Influence mechanism of different types of coal on selective nickle reduction in nickel laterite reduction roasting

      摘要:
      以某含镍1.86%(质量分数)、铁13.24%(质量分数)的红土镍矿为对象,分别采用石煤和无烟煤作为还原剂,考察了煤种对红土镍矿中镍的选择性还原的影响.结果表明,用石煤作为还原剂能够达到镍选择性还原的目的.X射线衍射及扫描电镜分析研究表明,还原过程中镍、铁先以镍纹石形式存在,随着煤用量增加,逐渐变为以铁纹石形式存在.同时随着煤用量的增加,焙烧后生成的含镍铁矿物中镍的比例逐渐递减,而铁的比例逐渐递增.石煤为还原剂时焙烧产物中主要以镍纹石的形式存在,同时金属铁的生成量比无烟煤作还原剂时低,因此采用石煤作还原剂比无烟煤作还原剂对镍还原具有更强的选择性,可以得到更高镍品位的镍铁精矿.
      Abstract:
      With a nickel laterite of 1.86% Ni and 13.24% Fe as a sample,the influence of different types of coal on selective nickel reduction in nickel laterite reduction roasting was studied with stone coal or anthracite as a reductant.It is indicated that nickel can be selectively reduced with stone coal as a reductant.The results obtained by X-ray diffraction(XRD) and scanning electron microscopy(SEM) show that taenite is the main form of nickel and iron in the roasted products when the dosage of coal is small,but the main mineral form changes into kamacite with the dosage of coal increasing.At the same time,with the dosage of coal increasing,the proportion of nickel decreases and the proportion of iron increases in Ni-Fe containing minerals produced after roasting.The roasted products are formed as taenite with stone coal as a reductant,the amount of gained Fe is lower but the selectivity for nickel is stronger than that with anthracite as a reductant,so Ni-Fe concentrate ores with high grade of nickel are obtained.
      作者单位: 北京科技大学金属矿山高效开采与安全教育部重点实验室,北京,100083
      刊 名: 北京科技大学学报 ISTICEIPKU
      年,卷(期): 2011, 33(10)
      分类号: TD925
      机标分类号: TF8 S56
      在线出版日期: 2012年4月21日