Theoretical Analysis on the Dynamic Characteristics of Blast Furnace in the Region between Melting Zone and Tuyere Level

Abstract

A mathematical model for analysing the dynamic characteristics of blast furnace in the region between melting zone and tuyere level are developed in this paper. On the basis of this model, the fundamental informations on the responses of both the location of melting zone and temperature of molten materials at the tuyere level to the step changes of blast temperature, steam ratio, blast volume and oil-injection rate have been obtained with the aid of digital computer.
Three principal time constants, i. e., time constant concerning the accumulation of materials in melting zone, one related to the accumulation of heat in coke zone supposedly located below melting zone and one connected with the shifting process of melting zone, have been taken into account in the analysis. It has been found that the shifting process of melting zone affects severely on the dynamic behavior of blast furnace, since the time constant connected with this process becomes large value such as several hours.