METHOD FOR PREVENTING BLOWOFF IN BLAST FURNACE OPERATION

PURPOSE:To provide a method for preventing blowoff caused by gap developing a furnace wall part in a blast furnace shaft part. CONSTITUTION:At the time of detecting the developing position of the gap, a switch valve 22 of a gas pressure exhaust pipe 21 at the developing position of this gap 3a or the neighborhood thereof is opened, and the gas in the gap 3a is discharged into the air. At the time of confirming the elimination of the gap 3a with a gap detecting sensor, the switch valve 22 is closed. By this method, the blowoff can be prevented from happening without reducing the production and the lowering of the gas utilizing ratio and the utilizing loss of the sensible heat caused by the blowoff and the increase of fuel ratio accompanied with these can be prevented.