BLOWING-OUT OPERATION OF BLAST FURNACE

PURPOSE:To safely adjust the temp. of gas from the top of a blast furnace without the need to consume expensive inert gas for cooling, by injecting blast furnace gas from which dust has been removed by wet process into the furnace inresponse to the falling of charged matter in the furnace. CONSTITUTION:In-furnace gas formed in the blast furnace is let flow through dust catchers 4, 5 to remove dust from it and to lower its temp. This low-temp. semipurified gas is injected into the furnace through in-furnace injection piping 3 provided at the top of the furnace and each stage of its shaft. The gas from the top of the furnace is cooled, when charged matter 2 in the furnace is let gradually fall down and reduced in volume by discharging it after the charge of raw materials in the blast furnace is stopped. Hence the temp. of gas from the top of the furnace is safely adjusted without the need to consume expensive inert gas for cooling.