The effect of slag attack to periclase-carbon refractory with calcium fluoride containing slag

• Main Authors: Kuo-Hung Yang, 楊國泓
• Other Authors: 吳威德
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/73116625520958246485

碩士 === 國立中興大學 === 材料科學與工程學系所 === 103 === The observation of slag attack to periclase-carbon refractory with slag in different concentration of calcium fluoride to realize the mechanism of slag corrosion with calcium fluoride containing. The slag corrosion goes serious with more calcium fluoride containing in the slag in 0%, 5%, 10% concentration of calcium fluoride. The corrosion index has been taken with comparison of cross-sectional area of samples between before and after the slag attack test. It’s found that the percentage of corrosion index is 4.93% in the slag without calcium fluoride containing and 7.52% in the slag with 10% calcium fluoride containing after 60 minutes immersion. It shows the slag corrosion goes serious with more calcium fluoride containing in the slag. The slag penetration to periclase-carbon refractory is worse with more calcium fluoride containing. It’s found that the penetration of slag with 10% calcium fluoride containing is more serious than without calcium fluoride containing by SEM observation, and the concentration of fluoride in slag is higher inside the refractory brick than outside. That means fluoride will become compound with low melting temperature that can bring serious penetration. Furthermore, the magnesia of refractory will be dissolved more with more calcium fluoride containing because the saturation of magnesia has been lifted up. The magnesia solubility from periclase-carbon refractory is about 11% in the slag without calcium fluoride containing and 125% in the slag with 10% calcium fluoride containing. It tells more magnesia solubility will lead serious slag attack with more calcium fluoride containing in the slag.