改质转炉渣中MgFe_2O_4的形成与磁选提铁  

Formation of Mg Fe_2O_4 and recycling of iron from modified BOF slag by magnetic separation

作　　者：薛鹏[1] 贺东风[1] 徐安军[1] 杨奇星[2,3] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]北方民族大学材料科学与工程学院,宁夏银川750021 [3]吕勒奥理工大学土木环境与自然资源工程系,瑞典吕勒奥se97187

出　　处：《钢铁》2017年第7期104-110,共7页Iron and Steel

基　　金：国家留学基金资助项目(留金发[2013]3009);国家自然基金重点资助项目(51534001);国家国际科技合作专项资助项目(SQ2013ZOG300003)

摘　　要：转炉渣中铁氧化物的回收一直是冶金领域的一个难题。通过对转炉渣进行适当地改质,将铁氧化物转变成强磁性矿物MgFe_2O_4再进行磁选,从而达到回收转炉渣中铁氧化物的目的。首先研究了碱度和煅烧温度对转炉合成渣中MgFe_2O_4形成的影响,然后对工业转炉渣进行了改质。试验方法包括XRD、SEM-EDS、Factsage热力学模拟以及化学元素分析。结果表明,试验中理想的碱度为2,理想的煅烧温度为1 250和1 300℃。通过向工业转炉渣加入6%的SiO_2,并从1 400℃以1℃/min的速度缓慢冷却到1 270℃,可使改质渣中形成MgFe_2O_4。磁选后磁性渣中的全铁质量分数为37.00%,比工业转炉渣中的全铁质量分数提高了15.80%,同时也比未经改质直接磁选的效果要好。Recycling of iron oxide from BOF slagshas always been a difficult issue in metallurgy. The core of this study was transforming the iron oxide into ferromagnetic phase MgFe204 by modifying industrial BOF slag appropriately first, and then recycling the iron resources by magnetic separation. The effect of basicity and calcination temperature on the formation of MgFe2O4 in synthetic BOF slags was investigated first, and then the industrial BOF slag was modified. Various experiments and analyses such as XRD, SEM-EDS, Factsage thermodynamic simulation and chemical analyses were conducted.The results show that the optimal basicity was 2, and the optimal calcination temperatures were 1 250 and 1 300℃. Moreover, MgFe204 was formed in modified BOF slag by mixing the industrial BOF slag with 6% SiO2 first, and then cooling the modified BOF slag from 1 400 to 1 270℃ at a rate of 1℃/min. After magnetic separation, the total Fe content in magnetic slag increased by 15.80%, to 37.00%, compared with that in the industrial BOF slag. This is better than the direct magnetic separation of iron oxide without any treatment.

关 键 词：转炉渣 Mg Fe2O4 铁氧化物 磁选 回收 

分 类 号：TQ138.11[化学工程—无机化工] X757[环境科学与工程—环境工程]