添加CaO对高炉喷吹煤粉燃烧机制的影响

Effect of Adding CaO on Combustion Mechanism of Pulverized Coal Injection in BF

CaO是一种适合高炉生产的煤粉助燃剂,通过热重-差热分析,其助燃机制是吸附挥发分,促使固定碳局部过热并增加燃烧活性,使煤粉在较低温度下开始燃烧。通过对未燃煤粉进行XRD、红外和SEM检测可知,随着助燃剂CaO的加入,未燃煤粉的微晶参数增大,芳香片层的堆砌高度升高0.002 4nm,层片直径增大0.036 2nm;添加CaO未燃煤粉的吸收峰在1 500和3 400cm-1处明显强于原煤的未燃煤粉;助燃剂CaO使未燃煤粉颗粒的平均粒径减小2.67μm,外观形貌变得不规则。

CaO is a kind of pulverized coal combustion improver which is suited for the blast furnace.It is adsorbing volatile,making fixed carbon overheat at local regions and increasing carbon activity,in this way,pulverized coal can take fire at lower temperature by DTA and TG curves analysis.Collecting unburned coal through simulating combustion conditions of blast furnace,analyzing XRD,IR spectrum and SEM,the microcrystalline parameters of unburned coal increased,the height and diameter of aromatic slices will increase 0.002 4 nm and 0.036 2 nm respectively as CaO joined.The absorption peak of unburned coal powder adding CaO is more obviously than raw coal in 1 500 cm-1 and 3 400 cm-1.The particles size of unburned coal powder reduced 2.67 μm by adding CaO,the morphological appearance become irregular.