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.