Phosphate Bonded High Alumina Brick Description
Phosphate bonded high alumina bricks adopt high alumina bauxite clinker as aggregate and powder material, phosphate or aluminum phosphate as binder. Phosphate bonded high alumina brick belongs to chemical bonded refractory brick, it is shaped by semi dry mold pressing and heat treated at 400~600℃. There are two kinds of phosphate bonded high alumina bricks, one is phosphate bonded high alumina brick, which adopts 42.5%~50% phosphate acid solution as binder, the other is aluminum phosphate bonded high alumina brick, which adopts, aluminum phosphate solution as binder. Phosphate bonded high alumina bricks are mainly used in cement kilns, such as transition zone, sintering zone, cooling zone, cooling machine, working lining of cement shaft kiln, etc.
Phosphate Bonded High Alumina Brick Characteristics
Phosphate bonded high alumina bricks have high mechanical strength, high refractoriness under load temperature, and good thermal shock resistance.
When small amount of ZrO2 is added into high alumina brick, thermal shock resistance of high alumina bricks can be improved, and the quantity of micro crack can be reduced.
Phosphate bonded high alumina brick, phosphate bonded high alumina wear resistant brick, stripping resistant high alumina brick and chemical bonded high alumina brick are widely used in cement kilns.
Compared with ceramic bonded high-alumina bricks, phosphate bonded high alumina bricks have better spalling resistance, but refractoriness under load temperature and corrosion resistance of phosphate bonded high alumina bricks are both lower. So some fused corundum or mullite can be added into raw material to improve corrosion resistance and refractoriness under load temperature.
Phosphate Bonded High Alumina Bricks Technical Index
Item |
Phosphate bonded high alumina bricks |
Aluminum phosphate bonded high alumina bricks |
Al2O3 % > |
76 |
78 |
Fe2O3 % < |
3.2 |
3.2 |
CaO % < |
0.6 |
0.6 |
Cold crushing strength Mpa > |
65 |
70 |
Bulk density g/cm3 |
2.65 |
2.70 |
Refractoriness under load ℃ > |
1350 |
1300 |
Refractoriness ℃ > |
1790 |
1790 |
Phosphate Bonded High Alumina Bricks Application
Phosphate bonded high alumina bricks are mainly used in cement kilns. For low production capacity cement kiln, with lower kiln temperature and frequent cease of kiln, phosphate bonded high alumina brick are used at sintering zone and transition zone. For cement kiln transition zone with unstable kiln coating or even naked bricks, spinel bricks are mainly adopted, but for small size kilns, phosphate bonded high alumina bricks are also widely used.
phosphate bonded high alumina bricks also have wide application in cement kiln decomposition zone, except for the hot end. The inner lining of cylindrical cooling machine has severe abrasion, so aluminum phosphate bonded abrasive brick can be used here. Phosphate bonded high alumina bricks are also used at rotary cement kiln hood, where abrasion is severe.