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The operational conditions, including temperature and gas composition, vary along the radial position in a blast furnace. Nevertheless, very few studies can be found in the literature that discuss how the reduction behavior of the ferrous burden varies along the radial position. In this study, the effect of the radial charging position on the reducibility of acid iron ore pellets was investigated using a laboratory-scale, high-temperature furnace in CO-CO₂-N₂ and CO-CO₂-H₂-H₂O-N₂ atmospheres up to 1100 °C. The experimental conditions were accumulated based on earlier measurements from a multi-point vertical probing campaign that was performed for a center-working European blast furnace. The main finding of this study is that the pellet reduction proceeded faster under simulated blast furnace conditions resembling those in the center area, compared to the wall area, because of a higher share of CO and H₂ in the gas. Therefore, the pellet charging position affects its reduction path in a blast furnace. Additionally, it was shown that the presence of H₂ and H₂O in the reducing gas enhanced the progress of reduction reactions significantly and enhanced the formation of cracks slightly, both of which are desirable in blast furnace operation. The reducibility data attained in this study are important in understanding how temperature and gas composition is connected to the reduction degree under realistic process conditions.

Most of world steel in 2018 has been produced from virgin iron ore via the blast furnace (BF)—basic oxygen furnace route. Therewith the BF is one of the most important unit processes in worldwide steel making. Among others, energy efficiency of the BF is dependent on coke reactivity. Coke gasification occurs via solution‐loss reactions either with CO₂ or H₂O. Herein, the gasification of coke is studied in CO–CO₂–H₂–H₂O–N₂ atmosphere simulating the BF conditions. The simulated atmospheres are based on the measurements from an actual BF. This research studies the effect of the composition of the BF atmosphere representing conditions near the wall as well as at the center and influence of the H₂O content on coke gasification under simulated BF conditions. It is found that the location plays a role in coke gasification: wall atmosphere yields higher coke gasification compared with center. Dynamic tests show that introduction of H₂ and H₂O in gas atmosphere fastens coke gasification by +119% at temperature range between 800 and 1200 °C in wall conditions. When H₂O is present in gas atmosphere, the mass loss of coke is also greater in both wall and center conditions.

A blast furnace (BF) is the dominant process for making iron in the world. The BF is charged with metallurgical coke and iron burden materials including iron ore pellets, sinter, and lump ore. While descending in the BF the charge materials reduce. The iron‐bearing materials should reduce fast and remain in the solid form until as high a temperature as possible to ensure reaction contact with reducing gas and iron oxides. Herein, the reducibility of the iron ore pellet, sinter, and lump ore in the BF shaft are focused on. The experiments are conducted isothermally with a blast furnace simulator (BFS) high‐temperature furnace at four different temperatures (700, 800, 900, and 1000 °C) for 300 min. The experimental atmosphere consists of CO, CO₂, H₂, H₂O, and N₂ simulating the conditions in the BF shaft. It is found that lump ore has lowest reduction rate in all test conditions, and at lower temperatures iron ore pellets reduce faster than sinter, and this is reversed at higher temperatures. Furthermore, the reduction rate of sinter and iron ore pellets begins to resemble each other at higher temperatures.

Using hydrogen as a reducing agent for iron production has been the focus of several studies due to its environmental potential. The aim of this work is to study the influence of H₂–H₂O content in the gas phase on the reduction of acid iron ore pellets under simulated blast furnace conditions. Temperature and gas compositions for the experiments were determined with multi-point vertical probes in an industrial blast furnace. The results of the reduction tests show that higher temperatures and H₂ content increase the rate and extent of reduction. For all the gas and temperature combinations, morphological, mineralogical, and microstructure changes were observed using different characterization techniques. Microscopy images reveal that H₂–H₂O, in the gas phase, has a positive influence on reduction, with metallic iron forming at the pellet’s periphery and core at lower temperatures compared to CO–CO₂–N₂ reducing gas. Porosity and surface area changes were determined using a gas pycnometer and the BET method. The results indicate that increasing the reduction temperatures and H₂ content results in greater porosity and a larger surface area. Moreover, carbon deposition did not take place, even at lower temperatures. A rate minimum was detected for pellets reduced at 800°C, probably due to metallic iron formation, hindering the diffusion of reducing gases through the product iron layer.

A blast furnace (BF) is the dominant process for making iron in the world. The blast furnace is charged with coke and iron burden materials including iron ore pellets, sinter and lump ore. While descending in the blast furnace the charge materials reduce. The iron bearing materials should reduce fast and remain in solid form until as high temperature as possible to ensure reaction contact with reducing gas and iron oxides. This research focuses on the reducibility of iron ore pellet, sinter and lump ore in the blast furnace shaft. The experiments were carried out isothermally with Blast Furnace Simulator (BFS) high-temperature furnace at four different temperatures (700oC, 800oC, 900oC and 1000oC) for 300 minutes. The experimental atmosphere consisted of CO, CO₂, H₂, H₂O and N₂ simulating the conditions in blast furnace shaft. It was found out that lump ore has lowest reduction rate at all test conditions. Iron ore pellets reduce fastest at lower temperature and is bypassed by sinter at higher temperatures. Furthermore, the reduction rate of sinter and iron ore pellets start to resemble each other in higher temperatures.

The need to increase efficiency and productivity within the metals industry in Germany is discussed, and a project is described involving five industry partners from the iron-and-steel and zinc industries in which an integrated approach was employed to represent an integrated steelmaking site, an electric arc furnace, the recycling of Zn-containing residues from the DK and Waelz processes and the recovery of Zn from Zn industry residues. Flow-sheet models were developed for the individual processes and the effect of re-using a residue within a particular process was simulated by applying sensitivity analysis to the single flow-sheet models. The flowsheets were linked using software which enabled data to be exchanged between the models. An example is presented covering the electric arc furnace steelmaking process and the recycling of the furnace dust in a Waelz kiln., The need to increase efficiency and productivity within the metals industry in Germany is discussed, and a project is described involving five industry partners from the iron-and-steel and zinc industries in which an integrated approach was employed to represent an integrated steelmaking site, an electric arc furnace, the recycling of Zn-containing residues from the DK and Waelz processes and the recovery of Zn from Zn industry residues. Flow-sheet models were developed for the individual processes and the effect of re-using a residue within a particular process was simulated by applying sensitivity analysis to the single flow-sheet models. The flowsheets were linked using software which enabled data to be exchanged between the models. An example is presented covering the electric arc furnace steelmaking process and the recycling of the furnace dust in a Waelz kiln.