铝热还原含稀土高炉渣直接合金化行为正交试验研究  

Behavior of Aluminothermic Reduction Rare Earth Containing Blast Furnace Slag for Direct Alloying using Orthogonal Testing

作　　者：瞿伟 任慧平[1,2] 智建国 董方[2] 齐建波 Qu Wei;Ren Huiping;Zhi Jianguo;Dong Fang;Qi Jianbo(School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China;Key Laboratory of New Metal Materials of Inner Mongolia,Baotou 014010,China;Baotou Iron&Steel(Group)Co.Ltd.,Baotou 014010,China)

机构地区：[1]上海大学材料科学与工程学院,上海200072 [2]内蒙古自治区新金属材料重点实验室,内蒙古包头014010 [3]包头钢铁集团,内蒙古包头014010

出　　处：《稀有金属》2020年第7期735-743,共9页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51261018);内蒙古科技大学科技创新项目(2017QDL-S02)资助。

摘　　要：研究了铝热还原高炉渣中稀土元素在铁水中的直接合金化行为。将高炉渣粉末和金属铝粉混匀后,压制成Φ15 mm的圆柱状块体,在高温管式炉中进行了高炉渣含铝压块自还原实验,利用扫描电镜(SEM)、能谱(EDS)分析及电子背散射衍射(EBSD)分析了自还原的微观过程。利用正交试验分析了保护渣量、高炉渣量、还原剂量和取样时间对直接合金化量的影响,采用电感耦合等离子体质谱仪(ICP-MS)检测直接合金化入铁水中的稀土量。结果表明,铝热还原高炉渣中稀土元素的微观过程可以分为两个阶段:首先是铝热还原硅元素的过程,SiO2→Al9Si→Si;然后是硅热还原钙和稀土元素的过程,CaO,RE2O3→CaSi2,(Ca0.8RE0.2)Si2。采用高炉渣进行稀土直接合金化的量随着还原剂的量、高炉渣的量和取样时间的增加而增加;随着保护渣的量增加而减少,各工艺参数对稀土直接合金化量影响的重要性和显著性排名为:还原剂量>保护渣量>取样时间>高炉渣量。The behavior of aluminothermic reduction rare earth containing blast furnace slag for direct alloying was studied.The blast furnace slag and aluminum powder were pressed intoΦ15 mm cylindrical pieces after mixing.The briquettes’self-reduction experiment was proceeded in the high temperature pipe furnace.The micro-process of the reduction was characterization analyzed by scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS)and electron backscatter diffraction(EBSD).The effect of addition amounts of protecting slag,blast furnace slag,reducing agent and sampling time on the results of direct alloying was analyzed using orthogonal testing.The quantitative analysis of rare earth which was in the molten iron by inductively coupled plasma source mass spectrometer(ICP-MS).The results indicated that,there were two steps during the micro-process of the aluminothermic reduction:firstly,silicon oxide was reduced by the aluminum,SiO2→Al9Si→Si.Then,calcium oxide and rare earth oxides was reduced by the silicon,CaO,RE2O3→CaSi2,(Ca0.8RE0.2)Si2.The amounts of rare earth direct alloying increased with the increase of blast furnace slag,reducing agent and sampling time,but decreased with the increase of the amounts of protecting slag.The importance and significance of influencing factors was ranked as:amount of reducing agent>amount of protective slag>sampling time>amount of blast furnace slag.

关 键 词：稀土 高炉渣 直接合金化 正交试验 铝热还原 

分 类 号：TF633[冶金工程—钢铁冶金]