高炉风口焦炭的形貌与冶金行为

 为了研究焦炭在风口区域的劣化过程,获取高炉风口区及风口区边缘焦炭样品,利用显微分光光度计和扫描电镜对焦炭与氧化性气体、炉渣和铁水的反应界面形貌与生成物进行了检测,分析了焦炭在风口区的冶金行为。研究结果表明,氧化性气体会以消耗碳元素方式侵蚀焦炭基质,炉渣则会进入焦炭气孔和裂纹中,通过反应、冲蚀和挤压气孔壁的方式瓦解焦炭。铁水主要通过渗碳作用侵蚀焦炭,残留的灰分会覆盖气孔壁表面,阻碍化学反应进行。风口区的焦炭已经高度石墨化,呈现大量片状石墨结构,微观结构的改变导致焦炭强度降低,最终瓦解粉化。焦炭内部的灰分、炉渣颗粒会与炉渣融合,形成终渣。

Morphology and metallurgical behavior of coke at tuyere of blast furnace

To study the coke deterioration process in the tuyere area, two coke samples were obtained from the edge of the tuyere and the tuyere area. The morphology and products of the reaction interface between coke matrix and oxidizing gas, slag and iron were detected by microspectrophotometer and scanning electronic microscope. The metallurgical behavior of coke in the tuyere zone was analyzed. The results show that oxidizing gas erodes the coke structure by consuming carbon matrix. Slag disintegrates coke by reaction, eroding and extruding gas coke pore walls. The hot metal at the edge of the tuyere area erodes coke mainly through carburization. The residual ash covers the surfaces of the pore wall, which may hinder the chemical reaction with slag and liquid iron. The disintegrated coke was highly graphitized, showing a flake graphite structure. The change of microstructure leads to the reduction of coke strength and finally disintegrated and powdered. After the coke disintegrates, the internal ash and slag powder mixes with the slag and finally forms the final slag.