An Integrated Approach to Model Blast Furnaces

The objective of this contribution is to introduce a discrete numerical approach that describes all relevant mechanisms above the cohesive zone within a blast furnace. It includes a thermal conversion module describing physico-chemical processes for ore and coke and a motion module which allows for spacial movement of the particles within the blast furnace. Both aspects are dealt with by the Discrete Particle Method (DPM), so that the sum of particle processes represents the global process. Conversion of particles is described by one-dimensional and transient differential conservation equations (mass, momentum, energy). Interaction between multiple particles takes place through gaseous intermediates, namely CO, CO2 and H2. For the bulk gas phase within the voidage between particles Computational Fluid Dynamics (CFD) is applied. In order to calculate mechanical interaction of the particles in a packed bed a discrete element technique (DEM) based on classical Newtonian dynamics was employed. This permits the prediction of trajectories of coke and ore particles. The presented model can act as tool to gain valuable insights into blast furnace processes and can serve as a toolbox for prediction and optimization of burden charging, burden movement, gas flow, reduction rates and reduction of coke consumption.