Multi-dimensional mathematical modeling of five phases in the blast furnace

A multi-dimensional mathematical model of blast furnace operation based on the multi fluid theory has been developed. The model considers gas, lump solid, fine powder, molten metal and slag as separate fluids. The behavior of each phase is described by the conservation equations of mass, momentum and thermal energy, and is affected from the other phases. Thus the interactions among existing phases are taken into account in the conservation equations by means of mass, momentum and heat exchange. In addition, all phases undergo reactions and phase transformations, therefore the rate equations of these phenomena based on the chemical kinetics and transport theory are used. The model is applied to three-dimensional analysis of actual blast furnace. Simulation results show that the radial distribution of the burden materials has strong effect on the formation of distributions of temperature, composition, and so on within the furnace. A circumferentially uniform distribution of charged material forms almost two-dimensional distributions of process variables in the middle and upper part of the furnace. On the contrary, the distributions show steep gradient not only in radial direction but also in tangential direction in the tuyere level.