TY - JOUR
T1 - Synthetic coal slag infiltration into varying refractory materials
AU - Kaneko, Tetsuya K.
AU - Thomas, Hugh
AU - Bennett, James P.
AU - Sridhar, Seetharaman
PY - 2012/10
Y1 - 2012/10
N2 - The infiltrations of synthetic coal slag into 99%Al 2O 3, 85%Al 2O 3-15%SiO 2, and 90%Cr 2O 3-10%Al 2O 3 refractories with a temperature gradient induced along the penetration direction were compared to one another. The infiltrating slag was synthesized with a composition that is representative of an average of the ash contents from U S coal feedstock. Experiments were conducted with a hot-face temperature of 1450°C in a CO/CO 2 atmosphere. Minimal penetration was observed in the 90%Cr 2O 3-10%Al 2O 3 material because interactions between the refractory and the slag produced a protective layer of FeCr 2O 4, which impeded slag flow into the bulk of the refractory. After 5 h, the 99%Al 2O 3 sample exhibited an average penetration of 12.7 mm whereas the 85%Al 2O 3-15%SiO 2 sample showed 3.8 mm. Slag infiltrated into the 99%Al 2O 3 and 85%Al 2O 3-15%SiO 2 refractory systems by dissolving the respective refractories' matrix materials, which consist of fine Al 2O 3 particles and an amorphous alumino-silicate phase. Due to enrichment in SiO 2, a network-former, infiltration into the 85%Al 2O 3- 15%SiO 2 system yielded a higher viscosity slag and hence, a shallower penetration depth. The results suggest that slag infiltration can be limited by interactions with the refractory through the formation of either a solid layer that physically impedes fluid flow or a more viscous slag that retards infiltration.
AB - The infiltrations of synthetic coal slag into 99%Al 2O 3, 85%Al 2O 3-15%SiO 2, and 90%Cr 2O 3-10%Al 2O 3 refractories with a temperature gradient induced along the penetration direction were compared to one another. The infiltrating slag was synthesized with a composition that is representative of an average of the ash contents from U S coal feedstock. Experiments were conducted with a hot-face temperature of 1450°C in a CO/CO 2 atmosphere. Minimal penetration was observed in the 90%Cr 2O 3-10%Al 2O 3 material because interactions between the refractory and the slag produced a protective layer of FeCr 2O 4, which impeded slag flow into the bulk of the refractory. After 5 h, the 99%Al 2O 3 sample exhibited an average penetration of 12.7 mm whereas the 85%Al 2O 3-15%SiO 2 sample showed 3.8 mm. Slag infiltrated into the 99%Al 2O 3 and 85%Al 2O 3-15%SiO 2 refractory systems by dissolving the respective refractories' matrix materials, which consist of fine Al 2O 3 particles and an amorphous alumino-silicate phase. Due to enrichment in SiO 2, a network-former, infiltration into the 85%Al 2O 3- 15%SiO 2 system yielded a higher viscosity slag and hence, a shallower penetration depth. The results suggest that slag infiltration can be limited by interactions with the refractory through the formation of either a solid layer that physically impedes fluid flow or a more viscous slag that retards infiltration.
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U2 - 10.1111/j.1551-2916.2012.05350.x
DO - 10.1111/j.1551-2916.2012.05350.x
M3 - Article
AN - SCOPUS:84867100210
SN - 0002-7820
VL - 95
SP - 3325
EP - 3333
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
IS - 10
ER -