METHOD OF HEATING OF BLAST-FURNACE AIR HEATER Russian patent published in 2015 - IPC C21B9/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, particularly, to heating of the blast-furnace air heater. Method includes combustion of fuel with low calorific value 9 MJ/nm³ or below in the combustion zone in the combustion chamber in the air heater. The gaseous combustion products flow through the refractory in the air heater and heat it. The fuel is combusted with presence of the oxidant containing at least 85% oxygen, at that recirculation of the gaseous combustion products is ensured to the combustion zone with possibility of fuel and oxidant mixture dilution in it to ensure the flameless combustion.

EFFECT: increased service life of the air heater.

15 cl, 6 dwg, 3 tbl