JPS54128917A - Method for controlling heat quantity of air sent from blast furnace - Google Patents

Abstract

PURPOSE:To maintain the potential heat quantity of hot air from a tuyere of a blast furnace at a certain limit value without lowering the thermal efficiency of a hot stove for the furnace by regulating the amt. of heavy oil blown from the tuyere in accordance with a temp. change of hot air from the stove. CONSTITUTION:The temp. of hot air from hot stove 3 of blast furnace 1 is measured with measuring unit 4 and inputted in operation unit 6 through input unit 5. In unit 6, the measured value is compared to upper and lower temp. limit values of hot air set in temp. setting unit 7. When the measured value exceeds the set upper limit value, cold air is mixed through output unit 8 to lower the value to the set upper limit value. When the measured value reaches the set lower limit value, the hot air is changed for hot air from other hot stove. On the basis of the relation between the temp. of hot air and the amt. of heavy oil blown, the amt. of heavy oil to be blown is decided in accordance with the measured temp. value, and heavy oil blowing regulator 9 is actuated through unit 8 to supply an adequate amt. of heavy oil to tuyere 2. The amt. of heavy oil blown into tuyere 2 is measured with heavy oil amt. measuring unit 10, and the difference between the measured value and the calculated amt. of heavy oil to be blown in unit 6 is calculated to allow regulator 9 to correct the difference.