The Wetting between Solid Iron and Liquid Slag

Wetting of Solid Iron by Molten FeO-Containing Slag

“…The results of contact angle measurement are represented in Table 1 and plotted against FeO content of slag in Figure 4. Data from the sources [8,9] were approximated by the curves and also represented in Figure 4 (for the data from [8] molar concentration was converted to mass concentration). As can be observed from Figure 4, slags with higher FeO content exhibit substantially lower contact angles with iron: Increase of FeO content from 28 to 62% is followed by fivefold drop in contact angle.…”

“…Iguchi et al [8] studied wettability of solid iron by the slags in various CO 2 /CO atmospheres, revealing that the liquid slags with more than 30 mol% FeO content perfectly wet the solid iron surface. It was found that the contact angle increases with the increase in the basicity of slags under the constant oxygen pressure, while addition of Al 2 O 3 and MgO has no significant effect.…”

“…In both referred above studies, a sessile drop technique was applied with the temperature level fixed for all experiments-at 1350°C in [9] and at 1450°C in [8]. Noteworthy, these temperatures exceed the liquidus temperature for the slag studied systems and generally correspond to the conditions when the liquid slag phase is already separated from the iron phase-whether it is a lower boundary of cohesive zone in the blast furnace or, for example, an iron nugget, produced in the innovative ITmk3 ironmaking process [10].…”

“…Noteworthy, these temperatures exceed the liquidus temperature for the slag studied systems and generally correspond to the conditions when the liquid slag phase is already separated from the iron phase-whether it is a lower boundary of cohesive zone in the blast furnace or, for example, an iron nugget, produced in the innovative ITmk3 ironmaking process [10]. In other words, by 1350°C a primary slag should be already long ago separated from the sponge iron, so the data available from the referred above studies [8,9] are not very relevant to the conditions of sponge iron and primary slag interaction preceding their separation into the flowable phases.…”

“…Experimental approach with fixed temperatures, applied in [8,9], allows for comparison of the wetting conditions in different slag systems. However, in reality, the temperature when primary slag and iron sponge separate into the independent liquid phases depends upon the reducing potential of gas, the reduction degree of the material and the gangue composition.…”