Influence of temperature and slag composition on wetting behavior of titanium-containing blast furnace slag and tuyere coke

The wetting behavior of slag-coke is a crucial factor influencing the permeability of the lower part of the blast furnace. However, a systematic understanding of the wetting behavior and underlying mechanisms between titanium-containing slag and tuyere coke remains lacking. The sessile drop method was employed to explore the effects of temperature, binary basicity, FeO, and TiO₂ contents on the wetting behavior of titanium-containing slag and tuyere coke. The results indicate that increasing the temperature enhances the adhesion and wettability of the droplet, reducing the contact angle. Meanwhile, it accelerates the chemical reactions between slag and coke, leading to faster equilibrium. Conversely, increasing slag basicity elevates the contact angle by inhibiting chemical reactions at the slag-coke interface. This inhibition reduces both contact area and depth, thereby hindering slag droplet spreading on the coke surface. The contact angle decreases as the FeO content in the slag increases. Notably, the increase in TiO₂ content has a dual effect on slag-coke wettability. Initially, it promotes wetting by reducing surface tension and lowering the contact angle. While the TiO₂ content exceeds 20 wt.%, Ti(C, N) forms a barrier layer at the slag-coke interface, hindering the contact between slag and coke and resulting in an increased contact angle.