Mechanism of Flow Resistance of Gas through the Fused Packed Bed

Abstract

An experiment and theoretical analysis on the flow resistance of gas through the fused packed bed were carried out for the calculation of gas flow near the cohesive zone in the blast furnace. The pressure drop was measured for the packed bed of prereduced pellets and sinter which were prepared to be various degree of shrinkage.
In the case of unfused packed bed, the observed value of the pressure drop showed good agreement with the value calculated by Ergun equation. However in the case of fused packed bed, the observed pressure drop showed a trend to deviate largely from Ergun equation as the degree of shrinkage increased. It was found that the experimental results were expressed well by the equation derived on the basis of the new mechanism proposed here that the pressure drop was caused by flow resistance of gas passed through the narrow slit between fused particles, just like the oliffice.
On the other hand, an attempt was made to express the shrinkage obtained by experiments as the equation, in order to predict the degree of shrinkage of iron are under various degree of reduction and temperature in the blast furnace.