1979 Volume 65 Issue 1 Pages 44-52
The gas temperature distribution in the throat of the blast furnace is divided into two patterns. One is named the spire type, in which the temperature is extremely high only in the central narrow part. Another is named the hill type, in which the temperature is high over the wide region of center.
The gas temperature distribution seems to be closely related to the descending rate of burden. For the spire type, the descending rate measured by a sounding probe is higher than the average rate calculated from the charging volume of burden. For the hill type, in which the measured rate is lower than the average, the descending rate in the central part is thought to be higher than the average.
The difference in descending rate between the central and the peripheral parts results in variation of the distribution of ore to coke ratio in stack. The variation of the layer thickness of burden in throat is theoretically calculated considering the distribution of descending rate.
The distribution pattern of top gas temperature is closely related to the thermal condition of blast furnace, and its change usually occurs six to ten hours before the beginning of variation in the temperature of pig iron.
