A two dimensional mathematical model is developed describing four phase chemical reactions, motion, and heat transfer in the blast furnace. The four phases are gas, lump solid, liquid and powder. The model simultaneously calculates the steady state composition, velocity, temperature, and volume fraction of all four phases. The predicted gas, solid and liquid phase compositions are plausible, but the fines dynamic holdup distribution is sensitive to the fines consumption processes in the raceway. The model has also been extended to include silicon transfer reactions. Compared to the base calculations, the predicted cohesive zone position is higher and the bosh is cooler when silicon transfer is included. The model predicts SiO generation from both coke ash silica and molten silica, the latter being the main contributor to hot metal silicon content in the case considered.