SIMULATION OF THERMOCHEMICAL AND THERMOMECHANICAL LOAD IN BLAST-FURNACE HEARTH

All investigations made in the course of the present inquiry aimed at developing proposals for the optimisation of blast furnace bottom and hearth refractories by means of experimental tests. Furthermore, the t ests are intended to develop new solutions for prolongation campaign l ife of blast furnace linings by applying the finite-element method. In the model calculations, particularly those bricks having a high therm al conductivity, showed high resistance to crack and spall formation. In comparison to standard or microporous grades, graphite containing c arbon blocks lower the risk of tensile cracks. By additionally doping graphite containing grades with aluminium oxide and silicon, high resi stance against pig iron dissolution and infiltration can be reached. M etallurgical coke content proved disadvantageous in the brick, because due to its high porosity the content can be infiltrated additionally into the porous binding matrix. Reduced flow in the brickwork and, thu s, reduced convective heat transfer lead to reduced tensile levels in the brickwork. By adapting the pool depth and tap hole length, particu larly the linings in the bottom and tap hole area will be relieved the rmically. In addition to the required stability of coke particle size and its large particle diameter to ensure an equally distributed pig i ron flow through the dead man, the dead man should also have good carb urization capacities. When comparing the dissolving inclination by tem perature reduction at the internal hearth wall side to the doping infl uence, it becomes clear that wear can be reduced much more efficiently by adding aluminium oxide than by increasing cooling measures.