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The lateral flow of gas–powder through a packed bed in a cold model is studied to understand the flow and holdup behaviour of powder in the presence of a cavity, nozzle (tuyere) protrusion, and decreasing gas condition, a system used in the ironmaking blast furnace. Experiments conducted in the current study included a two‐dimensional (2D) slot‐type packed bed. A previously published mass balance and elutriation velocity concept formed the basis for accurately quantifying the static and dynamic powder holdups. Experiments conducted under different conditions such as powder size and flux, gas flow rate, and packed particle density and size resulted in quantifying the powder holdups. The pressure drop in both horizontal and vertical directions is studied in all two‐phase flow experiments. The formation of the static holdup with time in the packed bed is studied. The reproducibility of the experiments was confirmed. The static holdup inside the packed bed at various locations along the vertical direction (i.e., height) is also quantified. The static holdup correlation developed based on experimental data resulted in a 95% confidence interval. Static powder holdup increases with a decrease in the superficial gas velocity, an increase in the size of the powder particle, and powder flux. Dynamic holdup also showed a similar trend.

Operational stability and productivity of an iron-making blast furnace relies on the permeability of the bed, which is adversely affected by the accumulation of unburnt coal and fine coke powder resulting from Pulverised Coal Injection (PCI) and coke degradation. Stable operation at a high PCI rate necessitates an understanding of gas-fine powder distribution, which is affected by the cohesive zone, and raceway shape and size. A computational study of a laterally injected gas-fine powder flow through a tuyere, into a packed bed is conducted in the presence of raceway and cohesive layers. An experimental correlation is used to predict the static holdup. The effect of operational parameters such as gas flow rate, particle and fine properties, and structural parameters such as cohesive zone configuration, porosity, and tuyere protrusion are analysed. Sensitivity analysis shows raceway shape, size, and interaction with the cohesive blocks affects the distribution and accumulation of fine powder.

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