1. College of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China 2. Department of Long Product, Tangshan Iron and Steel Company, Hebei Iron and Steel Group, Tangshan 063016, Hebei, China 3.College of Metallurgy & Energy, Key Laboratory of the Ministry of Education for Modern Metallurgy Technology, North China University of Science and Technology, Tangshan 063009, Hebei, China
Preparation and Metallurgical Analysis of High Activity Burnt Lime for Steelmaking
1. College of Metallurgy, Northeastern University, Shenyang 110819, Liaoning, China 2. Department of Long Product, Tangshan Iron and Steel Company, Hebei Iron and Steel Group, Tangshan 063016, Hebei, China 3.College of Metallurgy & Energy, Key Laboratory of the Ministry of Education for Modern Metallurgy Technology, North China University of Science and Technology, Tangshan 063009, Hebei, China
ժҪ Burnt lime is an important material in steelmaking and its activity degree is a key factor for liquid steel quality. The burnt lime was made by the calcination of limestone in a high pressure electric furnace. The burnt lime mineralogical phases and micro��morphologies were characterized by X��ray diffraction (XRD) and field emission scanning electron microscopy (FE��SEM). The burnt lime activity degree was determined by acid��base titration, the burnt lime pore distribution was measured by mercury intrusion porosimetry (MIP), and the thermal effect of a mixture of burnt lime and slag was measured by differential scanning calorimetry (DSC). The results showed that the CaO grain size and pore size of burnt lime made under high pressure were larger than those of burnt lime made under atmospheric pressure. The CaO grain size and pore size increased and the laminate phenomenon also occurred clearly under high pressure. The activity degree of burnt lime made under high pressure was greater than that made under atmospheric pressure. The maximum activity degree was 437 mL for burnt lime made under a pressure of 0��4 MPa. For the same ratio of CaO to SiO2, the melting temperature, hemisphere temperature and fluidity temperature of slag decreased with increasing burnt lime activity degree. The higher the activity degree the burnt lime had, the better the slag forming occurred. It was advantageous for 2CaO��SiO2 and 3CaO��SiO2 forming at lower temperatures if the burnt lime activity degree was increased.
Abstract��Burnt lime is an important material in steelmaking and its activity degree is a key factor for liquid steel quality. The burnt lime was made by the calcination of limestone in a high pressure electric furnace. The burnt lime mineralogical phases and micro��morphologies were characterized by X��ray diffraction (XRD) and field emission scanning electron microscopy (FE��SEM). The burnt lime activity degree was determined by acid��base titration, the burnt lime pore distribution was measured by mercury intrusion porosimetry (MIP), and the thermal effect of a mixture of burnt lime and slag was measured by differential scanning calorimetry (DSC). The results showed that the CaO grain size and pore size of burnt lime made under high pressure were larger than those of burnt lime made under atmospheric pressure. The CaO grain size and pore size increased and the laminate phenomenon also occurred clearly under high pressure. The activity degree of burnt lime made under high pressure was greater than that made under atmospheric pressure. The maximum activity degree was 437 mL for burnt lime made under a pressure of 0��4 MPa. For the same ratio of CaO to SiO2, the melting temperature, hemisphere temperature and fluidity temperature of slag decreased with increasing burnt lime activity degree. The higher the activity degree the burnt lime had, the better the slag forming occurred. It was advantageous for 2CaO��SiO2 and 3CaO��SiO2 forming at lower temperatures if the burnt lime activity degree was increased.
Hua��qiang HAO,,Yu��zhu ZHANG,,Su��ju HAO,Chao��fa ZHANG,Wu��feng JIANG,Peng��hui CUI. Preparation and Metallurgical Analysis of High Activity Burnt Lime for Steelmaking[J]. �й������ڿ���, 2016, 23(9): 884-890.
Hua��qiang HAO,,Yu��zhu ZHANG,,Su��ju HAO,Chao��fa ZHANG,Wu��feng JIANG,Peng��hui CUI. Preparation and Metallurgical Analysis of High Activity Burnt Lime for Steelmaking. Chinese Journal of Iron and Steel, 2016, 23(9): 884-890.
2016, Vol. 23 
