Mathematical model of burden distribution in bell-less top blast furnace

The burden distribution in the shaft of blast furnace is known to affect the gas distribution, heat transfer, and chemical reactions inside the furnace. However, the internal layer structure of burden in the shaft cannot be directly measured. Hence, a mathematical model for evaluating burden profile and layer structure was established. A sensitivity analysis based on the model was implemented to elucidate the effect of some factors on the burden distribution, including the stockline height and the mass of central coke. The results show that the width of funnel zone widens with the increase in stockline height, and the mass percentage of ore to coke in this zone slightly increases. Besides, the mass of central coke shows a significant influence on the width of coke channel, and 2% of batch mass of coke is recommended to implement central coke charging operation. The model has been indirectly verified by the gas temperature in operating blast furnace and successfully applied to online evaluate burden distribution.