In the present work, the reaction between a molten iron drop and dense alumina was studied using the X-ray sessile-drop method under different oxygen partial pressures in the gas atmosphere. The changes in contact angles between the iron drop and the alumina substrate were followed as functions of temperature and varying partial pressures of oxygen in the temperature range 1823 to 1873 K both in static and dynamic modes. The results of the contact angle measurements with pure iron in contact with dense alumina in extremely well-purified argon as well as under different oxygen partial pressures in the gas atmosphere showed good agreement with earlier measurements reported in the literature. In the dynamic mode, when argon was replaced by a CO-CO 2 -Ar mixture with a well-defined in the gas, the contact angle showed an initial decrease followed by a period of nearly constant contact angle. At the end of this period, the length of which was a function of the imposed, a further steep decrease in the contact angle was noticed. An intermediate layer of FeAl 2 O 4 was detected in the scanning electron microscope (SEM) analysis of the reacted substrates. An interesting observation in the present experiments is that the iron drop moved away from the site of the reaction once the product layer covered the interface. The results are analyzed on the basis of the various forces acting on the drop.

The X-ray sessile-drop method was employed in the present investigation to measure the contact angle between liquid iron and a silica substrate under argon as well as CO-CO 2 -Ar atmospheres in the temperature range of 1823 to 1833 K. In the latter case, the measurements were carried out in the dynamic mode, and the contact-angle changes were followed as a function of time as oxygen in the gas dissolved in the metal. The static measurements in argon showed that the contact angles in the experimental temperature range are of the order of 135 deg, similar to those observed in the case of the alumina substrate. In the dynamic mode, oxygen partial pressures varying between 9.9и10 Ϫ4 and 1.5и10 Ϫ2 Pa were imposed on the system. In these experiments, the contact angle decreased in two stages, with an intermediate steady-state region. Fayalite slag, formed due to the reaction between the metallic phase and the substrate, was found to accumulate around the drop. The results are of relevance in understanding the mechanism of corrosion of silica-containing refractories by molten iron.

In the present work, reactions occurring between molten iron containing varying amounts of oxygen and mullite substrate were investigated through optical Sessile drop experiments. The reactions were followed in static as well as dynamic modes through contact angle measurements. Further, the reactions were followed as functions of time, temperature and oxygen partial pressure. The latter was changed by means of imposing a gas mixture of Ar-CO-CO 2 into the furnace.The results showed that the contact angle between the substrate and the iron in purified argon gas was lower than the contact angles reported in literature for alumina and silica. Formation of a ternary slag during the reaction was observed and was subjected to SEM and EDS analysis. The thermodynamic criteria for slag formation and possible mechanisms of the reaction are discussed in the light of the experiments.The results are of relevance in understanding the mechanism of corrosion of aluminosilicate refractories by molten iron.

BiPCI technology of pulverized coal injection for blast furnace ironmaking was applied to No.2 Blast Furnace of SSAB Oxelösund in Sweden, and notable effectiveness of this BiPCI practice at SSAB has been achieved. The results show that if the tuyere injection rate of pulverized coal is kept nearly unchanged, (1) BiPCI can increase the overall coal rate and decrease the coke rate. When the second injection rate of pulverized coal attains 5 kg/tHM, the coke rate could be reduced by 5 kg/tHM; (2) BiPCI can increase the burden permeability, decrease the pressure drop of the furnace, and produce proper gas flow distribution, which is favourable to keep smooth running of the blast furnace and decrease the total reducing agent rate (RAR). During the test, the RAR showed a decrease by 2.8 kg/tHM (corrected RAR by 1.45 kg/tHM); (3) The pulverized coal through the second injection can be effectively used to protect the coke from fast degradation and improve the coke strength in the blast furnace, which is favourable to lower the high requirement on the coke quality under high coal rate operation.

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