CONVERT MELTING SLAG DIRECTLY INTO HIGH BASICITY GLASS- CERAMIC

摘要

Utilization of high-quality heat in melting slag is a great challenge for iron and steel industry. In the paper, a new method is put forward to concurrently utilize heat and slag by converting the melting slag directly into high valued materials, slag glass-ceramic. A glass-ceramic with a higher basicity of 0.7 than traditional basicity of 0.45 was prepared from steel-making slag in order to utilize more hot melting slag. Effects of Al_2O_3 on its crystallization processes were researched by XRF, DTA, XRD and SEM. Results show that Al_2O_3 in glass-ceramic would have great effected on its property. When the Al_2O_3 content ranges within 12%~15%, glass-ceramics with basicity of 0.7 could reach the best performances. The change of dominant phase in glass ceramics from akermanite and wollastonite to akermanite and gehlenite would significantly degrade its mechanical property. An increase of Al_2O_3 content leads to a rise of the viscosity and crystallization activation energy of the glass, while results in increasing sintering temperature and crystallization temperature of glass, which contributed to its fully crystallization and densification process.