Al2O3–Cr2O3 refractories used in waste-melting furnaces. By selection of appropriate
TiO2–Al2O3 and total TiO2 and Al2O3 content in the matrix, and addition
of appropriate amounts of preformed spinel, MgO–Al2O3–TiO2 refractories
with excellent properties can be fabricated. Table 8 compares properties of developed
MgO–Al2O3–TiO2 bricks with those of MgO–Cr2O3 bricks (after (68)).
Most of the properties of MgO–Al2O3–TiO2 bricks are close to or better than
those of the MgO–MK bricks. The bricks were trialed in RH vessels (mainly
the lower vessel and snorkel) and showed longer service life than MgO–MK
bricks. The better performance of MgO–Al2O3–TiO2 bricks is attributed to
the following factors: (1) TiO2 and MgO in the bricks react with the slag CaO
and Al2O3 to form high-melting CaO . TiO2 and MA, respectively; (2) use of
TiO2 reduces slag wettability; and (3) TiO2 forms a solid solution with MA