Abstract: A two-dimensional packed bed model was established with 1∶25 scale for simulating the PCI (pulverized coal injection)process and the Bi-PCI (bisegment pulverized coal injection)process based on similarity theory. The distributions of powder and pressure were investigated when PCI and Bi-PCI were used respectively. The results showed that the pulverized coal mainly accumulates in the lower part of packed bed， and the accumulation of pulverized coal decreases with increasing height of packed bed. The pulverized coal from the second lance accumulates in the edge region of the packed bed， and the holdup of the mid region is from the tuyere. At the same conditions， the distribution of pulverized coal becomes more uniform at height direction， and the permeability of packed bed is improved when Bi-PCI is adopted. So the pressure drop in packed bed is reduced by 29% compared with the PCI， mainly because the pressure drop significantly decreases in lower part of packed bed. The pulverized coal that have been injected by the secondary lance has little influence on the pressure drop in the upper of the packed bed.

Key words: blast furnace, Bi-PCI, distribution of pulverized coal, pressure drop, packed bed