PURPOSE: To eliminate the need to set the capacity of a dust collector at an excessive value and to reduce the cost of equipment when the tap hole of a blast furnace is opened in an early stage, by measuring a change in the temp. of the tap hole with a sensor and controlling the volume of air for dust collection according to the measured value.
CONSTITUTION: A change in the temp. of the tap hole 2 of a blast furnace is measured with a temp. sensor T fitted to the tip of a metallic bar 4 and the measured value is recorded on a temp. recorder 8. At the same time, the volume of air sucked by a dust collector 5 behind an exhaust fan 6 is automatically controlled according to the temp. change and the volume of air for dust collection at the tap hole 2 is increased to prevent the generation of dust. In order to cope with an abnormal state of the tap hole 2, the clogging of the tap hole 2 with a mud gun 3 is prepd. according to the value on the recorder 8.
KOSHI HIDEYUKI
SAITO NORIO