Premium
Synthetic Coal Slag Infiltration into Varying Refractory Materials
Author(s) -
Kaneko Tetsuya K.,
Thomas Hugh,
Bennett James P.,
Sridhar Seetharaman
Publication year - 2012
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1551-2916.2012.05350.x
Subject(s) - materials science , penetration (warfare) , dissolution , amorphous solid , silicate , infiltration (hvac) , slag (welding) , refractory (planetary science) , metallurgy , coal , mineralogy , composite material , chemical engineering , chemistry , organic chemistry , operations research , engineering
The infiltrations of synthetic coal slag into 99% Al 2 O 3 , 85% Al 2 O 3 –15% SiO 2 , and 90% Cr 2 O 3 –10% Al 2 O 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 2 O 3 –10% Al 2 O 3 material because interactions between the refractory and the slag produced a protective layer of Fe Cr 2 O 4 , which impeded slag flow into the bulk of the refractory. After 5 h, the 99% Al 2 O 3 sample exhibited an average penetration of 12.7 mm whereas the 85% Al 2 O 3 –15% SiO 2 sample showed 3.8 mm. Slag infiltrated into the 99% Al 2 O 3 and 85% Al 2 O 3 –15% SiO 2 refractory systems by dissolving the respective refractories' matrix materials, which consist of fine Al 2 O 3 particles and an amorphous alumino‐silicate phase. Due to enrichment in SiO 2 , a network‐former, infiltration into the 85% Al 2 O 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.