Process for the preparation of pig iron or liquid steel precursors from starting materials containing iron ore

摘要

In a process for the preparation of pig iron or liquid steel precursors from starting materials containing iron ore which are reduced in a reduction shaft furnace by means of a reduction gas, where the reduced iron particles obtained are melted down in a melt-down gasifier with the introduction of coal and oxygen-containing gas with simultaneous formation of the reduction gas, the reduction gas is fed to the reduction zone of the reduction shaft furnace and, after passing through this, is drawn off as top gas, the following measures are taken to increase the capacity for the production of pig iron: - some of the starting materials containing iron ore are reduced and melted in a blast furnace, - CO2 is removed from the top gas leaving the reduction shaft furnace, - the substantially CO2-free top gas is mixed with hot nitrogen or hot nitrogen-and argon-containing gas and thus warmed to above 800 DEG C, the mixing being carried out in a very short time span while avoiding reaction of the CO2 gas, and - the warmed top has is introduced into the blast furnace as reduction gas.