Transient mathematical model of blast furnace based on multi-fluid concept, with application to high PCI operation

The ironmaking blast furnace is a counter current chemical reactor whose main purpose is to produce hot metal (pig iron) from iron oxides. In the furnace, five phases: gas, lump solids (iron ore, sinter, pellets and coke), liquids (pig iron and molten slag) and powders (tuyere injectants: pulverized coal, coke fines or dust from the lump coke) interact with one another. In order to evaluate productivity, energy efficiency and transient phenomena occurring in the blast furnace, a comprehensive two-dimensional transient mathematical model has been developed. The model was composed of conservation equations of mass, momentum, chemical species and thermal energy for all phases mentioned above. This model includes phase transformations and chemical reactions such as melting of pig iron and slag components, moisture evaporation, reduction of iron oxides, solution loss, coke and pulverized coal combustion, silica reduction and gas phase reactions. With this model, the transient behavior of the blast furnace process has been successfully predicted for different injection rates of pulverized coal.