(1. 昆明理工大学 真空冶金国家工程实验室，昆明 650093；
2. 昆明理工大学 云南省有色金属真空冶金重点实验室，昆明 650093；
3. 昆明理工大学 云南省复杂有色金属资源清洁利用国家重点实验室(培育基地)，昆明 650093；
4. 昆明理工大学 冶金与能源工程学院，昆明 650093)
摘 要: 采用物料氧化镁还原率、XRD、SEM等手段与方法研究真空条件下煅白碳热还原温度、物料配比、碳热还原保温时间等对碳热还原煅白制取金属镁工艺的影响。结果表明：在30~100 Pa时，碳热还原温度高于1 623 K后，氧化镁的还原率明显增加，有利于碳热还原反应的进行。随着焦煤还原剂与氧化镁摩尔比的增大以及碳热还原时间的延长，碳热还原反应反应速率加大，还原率提高，当碳热还原温度为1 623 K、还原时间为4 h、配碳比为1.6时，氧化镁还原率超过99%。因此，选择适当的焦煤还原剂与氧化镁摩尔比值以及碳热还原时间，在温度高于1 623 K条件下，将有利于碳热还原法炼镁过程的顺利进行与氧化镁还原率的提高。
关键字: 煅白；碳热还原；金属镁；真空冶金
（1. National Engineering Laboratory for Vacuum Metallurgy, Kunming University of Science and Technology,
Kunming 650093, China;
2. Key Laboratory for Nonferrous Vacuum Metallurgy of Yunnan Province, Kunming University of Science and Technology, Kunming 650093, China;
3. State Key Laboratory Breeding Base of Complex Nonferrous Metal Resources Clear Utilization in Yunnan Province, Kunming University of Science and Technology, Kunming 650093, China;
4. Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology,
Kunming 650093, China）
Abstract:The temperature of calcined dolomite carbothermic reduction, molar ratio and carbothermic reaction time by calcined dolomite carbothermic reduction in vacuum were investigated by MgO reduction rate, XRD and SEM. The results show that the reduction rate of MgO clearly increases when temperature is higher than 1 623 K at 30-100 Pa, which is beneficial to MgO carbothermic reaction. The carbothermal reduction reaction rate increases with the increase of the molar ratio of coking coal reductant and magnesium oxide and carbon thermal reduction time at the carbon thermal reduction temperature of 1 623 K, the reduction time of 4 h and carbon ratio of 1.6, the magnesium oxide reduction rate is over 99%. Therefore, selecting the appropriate molar ratio of coking coal reductant and magnesium oxide and carbon thermal reduction time is beneficial to carbothermal reduction process for magnesium smelting going smoothly and magnesium oxide reduction rate increasing at the temperature higher than 1 623 K.
Key words: calcined dolomite; carbothermic reduction; metal magnesium; vacuum metallurgy
