Incinerator designers have used 70% Al2O3 brick for years in the primary and
secondary combustion chambers of the kilns. For a long time, the 70% Al2O3
bricks would experience rapid wear in the fireball regions of the secondary combustion
chamber where conditions reach in excess of 17508C. This is also an area
where corrosive lime-alumina-iron oxide-silica slags coat the refractory walls.
The 70% Al2O3 bricks were replaced with alumina-chrome bricks
(Table 11), and service was extended. The alumina-chrome bricks initially exhibited
excessive spalling loss, resulting in the development of the “spall-resistant”
alumina-chrome bricks. These latter bricks have been a resounding success in
incinerator service.