China Nonferrous Metallurgy

Three kinds of refractory bricks, chrome corundum, magnesia-chromium corundum and sintered zirconium corundum, were selected to conduct erosion experiments and to explore the causes of erosion in different acid-base slag environments. The results show that in the acid slag environment, the corrosion resistance of chrome corundum bricks is better, the erosion of magnesia-chromium corundum bricks is more severe, and the erosion of sintered zirconium corundum bricks is obvious. With rising of temperature and time increase, chrome corundum brick comes the best in terms of corrosion resistance. The performance of magnesia-chromium corundum bricks in terms of corrosion resistance and thermal expansion resistance is not good. The erosion of sintered zirconium corundum bricks is more severe. Under neutral slag environment, the corrosion resistance of chrome corundum bricks is reduced, and the erosion is a little bit obvious. The corrosion condition of magnesia-chromium corundum bricks is relatively good, and a certain degree of cracks appear above the liquid surface line. The sintered zirconium corundum brick erodes faster, and there are obvious “grooves” at the liquid surface line. Under basic slag environment, the surface of the chrome corundum brick is eroded and deteriorated obviously. The erosion of magnesia-chromium corundum bricks is not obvious, and the erosion of sintered zirconium corundum bricks is obvious. The analysis on the causes of erosion shows that the raw incinerator slag contains Na₂O amorphous minerals and crystalline quartz, and the added calcium oxides reacts with the chemical composition of the refractory material to cause erosion, and the erosion rate is related to the chemical composition of the refractory material.