| In this paper, at first, the refining ladle refractory lining and the slag corrosion of which wassummarized systemically, the history and current development of slag resistance research wasreviewed specifically as well as the existing shortcomings. According to the fact that matrix isthe key for slag resistance, the enhancement effect of ZrO2precursors and MgO micropowder onCorundum-spinel castable is studied, especially the viscous and inertial resistance coefficients ofmatrix. Then the resistance coefficients expression was optimized, the function relationshipsbetween the viscous and inertial resistance coefficient of Corundum-spinel castable matrix andthe microstructure parameters, fluid properties, and flow were established for the further study ofslag penetration process. Finally, based on the VOF model, the numerical simulation of slagcorrosion on Corundum-spinel castable was carried out using the commercial programmeFluent, and the effects of slag properties and material microstructure parameters on slagpenetration was discussed.The conclusions are as follows:1) The sintering characteristics including the bulk density, apparent porosity and averagepore-size of Al2O3-MgO castables matrix were improved， and the resistance coefficientsincreased by adding proper amount of ZrO2precursor, of which the proper amount is0.5wt%, orMgO micropowder, its favorable adding-amount is4.5wt%. Compared with the inertialresistance, the viscous resistance is the dominating resistance for gas flowing through the sample.Pore size is more crucial than apparent porosity for penetration resistance of matrix.2) With ZrO2precursor added, the heat conductivity of matrix increased at first and thendecreased, and have a peak value for0.5wt%ZrO2precursor. The heat conductivity of matrixcontinued to increase with increasing amount of MgO micropowder. The sintering characteristicsof matrix, both for the samples added with ZrO2precursor and the samples added with MgOmicropowder, was improved significantly with increasing sintering temperature, but the averagepore size enlarged. For the former, the resistance coefficient of matrix increased first and thendecreased, for the latter, the resistance coefficient decreased continually. The change of matrix’sheat conductivity varying with temperature has a converse trend compared with the resistancecoefficient.3) For the Al2O3-MgO castable with a apparent porosity,22%＜ε＜35%, and a averagepore-size,0.1μm＜d＜10μm, the expression of resistance coefficient of Al2O3-MgO castablematrix related to its apparent porosity and average pore-size can be manipulated to: The functional equations of apparent porosity ε(T), average pore sized(T), and coefficient A(T), B(T) in above equation about temperature T are as follows respectively, which is suitable for the T between1200℃～1600℃: e(T)=-4.9896+8.15e-3×T-3.05e-6×T2; d(T)=-3.0532+0.0032xT; A(T)=-2.12111×106+4485.94412×T-3.13124×T2+7.22653×10-4×T3;4) With the slag flow and material mico-structure taken into consideration, the expression of viscous resistance coefficient and inertial resistance coefficient of Al2O3-MgO castable matrix related to the property of the fluid, flow, and the microstructure parameters of matrix can be manipulated to: These equations above are suitable for Re<0.1.5) The VOF model combined with the porous medium model is suitable for the description of slag penetration on refractory, and the slag penetration depth of modeling is smaller than the result according to Bilkerman equation. Compared to the contact angle, viscosity has the most significant effect on penetration, and the surficial tension’s effect is the weakest. Compared to the apparent porosity of aggregates and pore size and apparent porosity of matrix, the pore size of aggregate’s effect on penetration is much more obvious. Thus, for light-weight castables that serve as ladle refractory lining, the average pore-diameter of the aggregates should be kept small enough, in order to ensure relatively favorable slag corrosion resistance. |
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