One way to decrease the reducing agent rate in a blast furnace (BF) is the lowering of thermal reserve zone (TRZ) temperature by using self-reducing pellets (SRP). The lower strength requirement of raw materials for small BFs allows the charging of SRP. In the scope of the current study, the behavior of SRP under the TRZ simulated conditions has been investigated. Coal, charcoal, and coke breeze were used as embedded reducing agents. The reduction experiments have been performed under different iso-and non-isothermal scenarios. A Tammann furnace laboratory rig and a simultaneous Thermogravimetric/ Differential Thermal Analysis (TG/DTA) experimental set were used for investigations. Mass loss, reduction degree, metallization degree, volume change, and reaction heat flow were examined. The results from experiments with TRZ condition show that embedded reducing agents, especially charcoal, promote iron oxide reduction in pellets. The crushing strengths of SRPs after both methods of hardening, fire-hardening and cement-bonded curing, and the reduction of cement-bonded SRP after curing have been investigated as well.

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In ladle metallurgy, the flow of purge gas through injectors promotes an effective mixing of the melt concerning composition and energy. In this work, different types of gas injectors, positioned eccentrically at 66% of the ladle radius are investigated in terms of the bubble size distribution, the resultant flow field velocity, and turbulent kinetic energy. The experiments are carried out in a 1:3 scale water model of a 185 t ladle using Particle Image Velocimetry (PIV) and image processing. It is shown that a porous plug provides more intensive bulk convection and a higher degree of turbulence than the other tested injectors. The differences are explained by the generation of smaller bubbles, which transfer more momentum into the liquid. The differences between the injectors are small, though. Thus, it is concluded that in comparison with other process parameters, the type of injector plays a minor role in the efficiency of ladle metallurgy.

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