Summary

Pulverized coal is the most common auxiliary fuel used in blast furnaces. Auxiliary fuels are used to replace expensive coke as a reducing agent for iron oxides. High amounts of pulverized coal injection lead to permeability changes in a blast furnace shaft together with an excess amount of unburnt coal. Permeability issues can be tackled with an adjusted charging program, but poor pulverized coal combustion will not enable cost efficient substitution of coke with coal. The only way to overcome this limit is to improve the conditions in pulverized coal combustion. The aim of this study was to create a combustion model for pulverized coal, which could be used to locate limiting factors in auxiliary fuel combustion in the actual blast furnace. Experimental results were used to validate the combustion model. The CFD model had a good agreement with experimental results with different types of coals. According to this study, this kind of combustion model can be used to study the blast furnace operation.