摘要
用X光透射装置研究煤还原新疆什可布台矿还原膨胀特性,发现反应性好的义马煤还原矿石发生恶性膨胀。用光学显微镜和扫描电镜观察了还原后矿石的微观结构变化,电镜下观察到“铁晶须”的存在。X射线衍射分析测量晶胞常数表明,铁氧化物晶格中渗入了杂质,促使“铁晶须”的生长,导致矿石还原时出现恶性膨胀。高温快速还原能减轻膨胀,降低粉化率。
X-ray apparatus was used to study the reduction-swelling behavior of the coal-reduced iron ore from Shikebutai,Xinjiang Uygur Autonomous Region,and catastrophic swelling was found in the ore reduced with the coal of high reducibility from Yima.Microstructural observations by microscope and SEM show that there exist whiskers in the ore after reduction. The lattice cell constant determined by XRD indicates that such whiskers grow out owing to the impurities penetrating into the lattice of ferric oxides and,therefore,result in catastrophic swelling during ore reduction.Rapid reduction at high temperature has been proved available to weaken swelling effect with comminution rate lowered.
关键词
铁矿石
恶性膨胀
显微结构
铁晶须
catastrophic swelling,micro-structure,whisker,lattice cell constant
