There is a consensus that complete conversion of the injected pulverized coal (PC) within the raceway zone is hardly possible, particularly at high injection rates. Therefore, formation, transportation, and consumption of coal residues or char outside the raceway as well as its interaction with solid, liquid, and gaseous media present in the furnace are vital for an efficient blast furnace (BF) operation. Herein, done in the scope of a European Research Fund for Coal and Steel project, two injection coals are selected and used to produce char. Chemical, physical, petrographic, and microstructural properties of produced chars are characterized. Char behavior and its effect on coke and iron burden are examined using numerous analytical, laboratory, and pilot‐scale facilities. Next, industrial trials are performed to evaluate the extent of char transfer within the BF shaft at high PC injection rates. The results of gas and temperature measurements as well as sampling of dust give new insights regarding the impact of high coal injection rates on the BF inner state. Data generated from the experimental results are used for mathematical modelling. The effects of char on the cohesive zone thickness, position, and gas permeability are investigated.

中文翻译：

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高炉喷吹煤焦的形成及其行为

有一个共识是，尤其是在高喷射速率下，很难在轨道区域内完全转换喷射的煤粉（PC）。因此，滚道外部的煤渣或焦炭的形成，运输和消耗以及其与炉中存在的固体，液体和气态介质的相互作用对于高效高炉（BF）操作至关重要。在此，在欧洲煤炭和钢铁研究基金项目的范围内，选择了两种注入煤并用于生产焦炭。表征了所产生的炭的化学，物理，岩石学和微观结构性质。使用许多分析，实验室和中试规模的设施检查了​​炭的行为及其对焦炭和铁负荷的影响。下一个，进行了工业试验，以评估在高PC注入速率下高炉内焦炭转移的程度。气体和温度测量以及粉尘采样的结果为高喷煤率对高炉内部状态的影响提供了新的见解。从实验结果生成的数据用于数学建模。研究了炭对内聚区厚度，位置和透气性的影响。