Effect of additives on formation of calcium ferrites in magnesia-riched sinters
YAO Jun-hao1,2,YANG Jun3,HAN Dong4,GUO Xing-min1,2
1. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China 2. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China 3. Technical Center, Laiwu Steel Group Ltd., Laiwu 271104, Shandong, China 4. Huiheng Metallurgical Materials Plant of Laiwu City, Laiwu 271100, Shandong, China
Abstract:Production of rich-containing MgO sinters has become one of the effective ways to solve the problems,such as high viscosity and low desulfurization ability of the slag which was brought by large use of high-alumina iron ores in blast furnace. However,rich-containing MgO raw materials decrease the quantity of binding phase during sintering process to make the strength of sinter worse. This study aims to increase the amount of calcium ferrite(SFCA) by adding additives with low melting point into iron ore fines to improve the quality of sinters. The B2O3,CaCl2 and Na2SiO3 were used as additives to add into high-alumina iron ore fines with rich-containing MgO. The effect of additives on sintering process was investigated according to the results of patterns and optical microstructure of sintered samples from XRD. The results showed that the three kinds of additives have a promotion to form SFCA,but the effects are different. When the mass percent of MgO is 4%,the appropriate amount(mass percent) of B2O3,CaCl2 or Na2SiO is 0.094%,0.470% and 0.470% respectively. It can promote SFCA formation with more amount,and little additive is good for acicular morphology. Another result indicates that increase of binding phase helps to generate more magnetite under the high content of MgO.
姚君豪,杨军,韩冬,郭兴敏,. 添加剂对高MgO烧结矿中铁酸钙生成的影响[J]. 钢铁, 2015, 50(2): 12-16.
YAO Jun-hao,,YANG Jun,HAN Dong,GUO Xing-min,. Effect of additives on formation of calcium ferrites in magnesia-riched sinters. Iron and Steel, 2015, 50(2): 12-16.
Mark I.Pownceby, Tim R.C.Patric.Stability of SFC (silico-ferrite of calcium): solid solution limits, thermal stability and selected phase relationships within the Fe2O3-CaO-SiO2 (FCS) system[J]. Mineral,2000,12:455-468
[10]
Mark I.Pownceby, Tim R.C.Patric.Stability of SFC (silico-ferrite of calcium): solid solution limits, thermal stability and selected phase relationships within the Fe2O3-CaO-SiO2 (FCS) system[J]. Mineral,2000,12:455-468