Effect of Na2CO3 and CaCO3 on Coreduction Roasting of Blast Furnace Dust and High-phosphorus Oolitic Hematite  

作　　者：曹允业 孙体昌 KOU Jue XU Chengyan GAO Enxia 

机构地区：[1]School of Civil & Environmental Engineering, Key Laboratory of High-Efficient Mining and Safety of Metal Mines, Ministry of Education University of Science and Technology Beijing, Beijing 100083, China

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2017年第3期517-524,共8页武汉理工大学学报（材料科学英文版）

基　　金：Funded by National Natural Science Foundation of China(No.51134002)

摘　　要：Iron was recovered from blast furnace dust and high-phosphorus oolitic hematite in the presence of Na2CO3 and CaCO3 additives. The functions of Na2CO3 and CaCO3 during the coreduction roasting process were investigated by XRD and SEM-EDS analyses. Results indicate that these additives not only hinder the reduction of fluorapatite, CaCO3 also decreases the P content of direct reduced iron（DRI） by increasing the reduction alkalinity. P remains as fluorapatite in the slag, which can be removed by grinding and magnetic separation under optimal conditions. The Na2CO3 promotes hematite reduction and improves the iron recovery（εFe） by replacing the FeO from fayalite, which results in quick growth and aggregation of metallic iron and improvement of ε（Fe） in DRI. A DRI with 91.88 mass% Fe, and 0.065 mass% P can be achieved at a recovery of 87.86 mass% under the optimal condition.Iron was recovered from blast furnace dust and high-phosphorus oolitic hematite in the presence of Na2CO3 and CaCO3 additives. The functions of Na2CO3 and CaCO3 during the coreduction roasting process were investigated by XRD and SEM-EDS analyses. Results indicate that these additives not only hinder the reduction of fluorapatite, CaCO3 also decreases the P content of direct reduced iron（DRI） by increasing the reduction alkalinity. P remains as fluorapatite in the slag, which can be removed by grinding and magnetic separation under optimal conditions. The Na2CO3 promotes hematite reduction and improves the iron recovery（εFe） by replacing the FeO from fayalite, which results in quick growth and aggregation of metallic iron and improvement of ε（Fe） in DRI. A DRI with 91.88 mass% Fe, and 0.065 mass% P can be achieved at a recovery of 87.86 mass% under the optimal condition.

关 键 词：Na2CO3 CaCO3 blast furnace dust high-phosphorus oolitic hematite coreduction roasting 

分 类 号：TF56[冶金工程—钢铁冶金] X757[环境科学与工程—环境工程]