Observation of the Effect of Various Operating Factors on the Cohesive Zone Using the Blast Furnace Irregularity Simulator

The blast furnace (BF) process is highly complex, involving multiple phases (gases, granular solids, liquids, and powders) undergoing various chemical and physical phenomena. Any improvement in BF productivity under a given set of operating conditions necessitates a better gas flow distribution through a layered burden structure in the BF. However, it is extremely difficult to directly measure or predict the internal flows in a BF. The main zone of unstable motion in a BF is generally the cohesive zone. Herein, the cause of unstable behavior in a BF is investigated by directly observing the behavior of the cohesive zone using a BF irregularity simulator. It is found that the shape of the cohesive zone is directly influenced by the blast conditions and the height of the deadman, as well as varied change. As the blast volume increased, the height of the top level of the cohesive zone increased and the change in the temperature profile of the cohesive zone according to the difference in blast volume. Thus, it is possible to understand and estimate the unstable motion in a BF under operation by observing the real-time behavior of the burden, using a BF irregularity simulator.