METHOD OF FORMING PROTECTIVE SKULL IN BLAST FURNACE HEARTH Russian patent published in 2004 - IPC

FIELD: ferrous metallurgy; blast furnace process; melting cast iron in blast furnaces. SUBSTANCE: proposed method includes delivery of titanium-containing skull-forming additive through channel or iron tap-hole together with tap-hole loam fed by means of gun for closing the iron tap-hole. Titanium-containing skull- forming additive is ground to size no less than 1 mm and is mixed in tap- hole loam in the amount of 5-30%, after which it is loaded in gun by first batch. After closing the tap-hole, tap-hole loam is forced into hearth for forming skull on walls in area of tap-hole. Skull-forming additive is introduced into hearth through all tap-holes according to results of monitoring the lining temperature at level of joint hearth wall and blast- furnace bottom at positive deviation of average lining temperature by more than 10 C. Upon revealing the sector at maximum lining temperature, skull additive is introduced into hearth through tap-hole in sector at maximum temperature at deviation from average temperature over circumference of hearth by more than 15 C. Used as titanium- containing skull-forming additive is rutile or ilmenite or blast-furnace slag of vanadium iron melting process or metallic concentrator from dump flag of vanadium iron melting process or combination of said components. EFFECT: enhanced efficiency; increased campaign of furnace. 4cl, 2 ex