Preparation and slag erosion resistance mechanism of MgAlON based composite refractories synthesized from solid waste

Abstract

Refractory waste is a typical industrial solid waste. Owing to technical reasons, most of the refractory waste is not efficiently utilized and causes environmental pollution. In this study, we explored a novel technology for the preparation of MgAlON based composite refractories using waste MgO-C and Al2O3-MgO-C refractory materials. The experimental results showed that higher sintering temperatures, enhanced the mechanics of the synthesized MgAlON based composite refractories. Its flexural strength and compressive strength reached 7.7 MPa and 15.87 MPa, respectively, as the sintering temperature increased to 1823 K. Additionally, the slag erosion resistance of the MgAlON based composite refractories was studied and was found to be significantly influenced by the temperature and duration of erosion. The erosion of MgAlON based composite refractories by metallurgical slag was controlled by a combination of chemical reaction and diffusion. The apparent activation energy of slag erosion was approximately 274.6 kJ/mol. During the erosion of MgAlON based composite refractories, the metallurgical slag mainly penetrated the material through its pores. The Si, Ca, and Ti elements in the slag diffused into MgAlON based composite refractories, whereas Mg and Al, diffused into the slag from the MgAlON based composite refractories.