The application of the Rist and Meysson model to the determination of the chemical efficiency of reduction of iron oxides in Blast Furnaces is shown in this book. This model allow us to know how far is the process from the limits imposed by the chemical equilibrium and heat balances. The model developed in an excel spreadsheet is able to read directly through the Plant Information System (PI) interfaces all the process information coming from the control systems and labs, allowing the operator to see the furnace deviation from the optimum technical feasibility. The operation line resulting...