Modelling combustion of pulverized coal and alternative carbon materials in the blast furnace raceway

The impact of injection lance design and injection materials on the combustion conditions inside the raceway of the blast furnace has been investigated. Operational injection tests in LKAB’s Experimental blast furnace have been conducted and data describing particle dispersion and temperatures at the tuyere was gathered. A three-dimensional, multiphase numerical model of pulverized material injection (pulverized coal and alternative carbon materials) was developed in order to increase the understanding of raceway conditions in terms of combustion efficiency and reaction rates. In total two different injection lances and two alternative carbon materials in varying blend ratios with pulverized coal were investigated in the numerical study. Simulation results agreed quite well to the experimental data. Furthermore, simulation results agree with published findings regarding the general effect of material properties of pulverized coal on combustion efficiency.