A blast furnace is modeled as a counter-current bed reactor filled with solid particles of coke and ore where the gas flows upward through the porous media while the bed material moves slowly in the countercurrent direction of the gas flow. An axi-symmetric two-dimensional steady state model is proposed to simulate the gas and the solid flow, where thermo-chemical reactions and heat transfer process are considered. It is assumed that two phases of solid and gas exist in the furnace. The charged material is treated as porous media constructed by alternative coke and ore layers, which have different permeability. The internal gas flow of the furnace is governed principally by burden distribution. For understanding of the influence of the burden distribution on the internal situation, the entire layer structure is predicted from the measured top layer structure and the solid flow is assumed as the potential flow. Using this burden distribution, the flow, energy, and chemical species conservation equations are derived for each phase. In addition, the phase mass generation/consumption caused by reactions, heat transfer between gas and solid phases, and the reaction heat are reflected in source terms in the governing equations. For several different L o /L c (layer thickness ratio of ore and coke layer) cases, layer structures are constructed and numerical simulations are conducted. The finite volume method was used for the numerical simulations. Through this approach, the flow, composition and temperature distributions within the furnace are numerically predicted.

Korea.Coke in the blast furnace experiences great changes in their properties during the blast furnace operation.Pulverized coal injection (PCl) into Characteristics of CokeProperties at Tuyere Level As reported before,5) four distinctive parts could be identified; bosh, raceway, bird's nest and deadmanas shown in Fig. 2(a)

Numerical simulation of blast furnace phenomena has significantly contributed to the better understanding of iron making process. Recent interest on minimizing fuel consumption and reducing environmental problems have also benefitted from the development of comprehensive simulation models based on physical principles. One of the under-developing fields, however, is related with the internal phenomena in the lower part of the blast furnace under the cohesive zone, where the liquid phase of metal and slag flows downward over the bed of solid coke particles. Hot flow of sluggish liquid phase is further complicated by the chemical reactions including the transfer of silica into the silicon in the hot metal. Silica enters the furnace as a constituent of coke ash and ferrous gangue, and exits as either molten silica in slag or dissolved Si in the hot metal. Silica reduction is an endothermic reaction, which would alter the heat transfer in the lower furnace, thus affecting the hot metal temperature.Effective flow in the dripping zone is important for stable operation of the blast furnace with high productivity of iron. Study of the liquid flow behavior and secondary reactions in a packed bed allows to investigate the effect of various operational changes in the dripping zone. In this research, a systematic numerical approach for the liquid flow is presented where the flow behavior is solved along with heat transfer associated with physic-chemical reactions among representative components.

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