Applications: rotary kiln lining by zone
For lime, magnesium-metal, zinc-oxide, alumina, incineration and cement kilns. Only product-to-zone correspondences published by Jinxing are listed.
The following is general material-selection guidance; the actual lining design depends on kiln data.
Cement rotary kiln (precalciner) — zone map
Zones are shown from the kiln inlet to the outlet. Select a zone (mouse, or Tab and Enter) to see typical conditions, main wear mechanisms and generic material classes.
Selected zone · Kiln
Upper transition zone
- Typical conditions
- Approx. 1200–1400 ℃ class; unstable coating, large temperature fluctuation, alkali and sulphur enrichment; high mechanical stress near the tyre
- Main wear mechanisms
- Thermal-shock spalling, cracking after alkali-salt densification, hot-face loss with falling coating, mechanical stress from shell ovality, hot-spot risk
- Generic material classes
- Magnesia-alumina spinel bricks (mainstream); silica-mullite or silica-mullite red bricks for small/medium kilns or milder conditions (depending on kiln data); flexible grades in the tyre area
Schematic, not to scale. Zone lengths depend on kiln size, fuel and operation and are set in the lining design. Temperatures are industry-indicative ranges (strongly dependent on kiln type, fuel and operation) used to describe service conditions; they are not measured values for any kiln.
Cement rotary kiln — Zone
| Zone | Typical conditions | Main wear mechanisms | Generic material classes |
|---|---|---|---|
| Kiln inlet / inlet chamberKiln | Medium temperature (approx. 800–1100 ℃ class); raw meal and kiln gas enriched in alkalis, sulphur and chlorine; prone to build-up | Alkali-salt infiltration and structural spalling, build-up and blockage, abrasion by raw meal | Anti-build-up (SiC-containing) castables, high-strength alkali-resistant castables, mullite castables; alkali-resistant bricks locally at the inlet |
| Calcining / preheating zone (safety zone)Kiln | Material approx. 900–1250 ℃ class; carbonate decomposition, alkali-salt condensation, possible ring formation | Alkali attack, thermal shock, abrasion, mechanical damage after ring formation | Silica-mullite bricks, silica-mullite red bricks, anti-spalling high-alumina bricks, alkali-resistant bricks; low-conductivity composite bricks where energy saving is required |
| Upper transition zoneKiln | Approx. 1200–1400 ℃ class; unstable coating, large temperature fluctuation, alkali and sulphur enrichment; high mechanical stress near the tyre | Thermal-shock spalling, cracking after alkali-salt densification, hot-face loss with falling coating, mechanical stress from shell ovality, hot-spot risk | Magnesia-alumina spinel bricks (mainstream); silica-mullite or silica-mullite red bricks for small/medium kilns or milder conditions (depending on kiln data); flexible grades in the tyre area |
| Burning zoneKiln | Material approx. 1450 ℃ class, higher flame temperature; a stable coating is normally present | Clinker-melt infiltration, thermal and chemical attack when the coating is unstable, redox fluctuation, mechanical stress | Magnesia-hercynite spinel bricks (mainstream chrome-free solution), magnesia-zirconia or dolomite basic bricks |
| Lower transition zoneKiln | Approx. 1300–1450 ℃ class, near the outlet; unstable coating, alternating hot/cold secondary air | Thermal shock, coating loss, clinker abrasion, chemical attack | Magnesia-alumina spinel bricks; high-wear silica-mullite bricks in some kilns |
| Cooling zoneKiln | Approx. 1100–1350 ℃ class; clinker cooling, hot secondary air, no or very thin coating | Clinker abrasion, thermal shock, erosion by hot secondary air | High-wear silica-mullite bricks, corundum-mullite bricks, anti-spalling high-alumina bricks |
| Kiln outlet / nose ringKiln | Hot clinker discharge, most severe thermal cycling, mechanical impact, nose-casting deformation | Abrasion, thermal shock, clinker erosion, lining loosening from nose-plate deformation | Corundum-mullite, corundum-SiC or mullite-SiC low-cement castables (often with steel fibres); nose-ring precast shapes |
| Preheater cyclonesExternal system | — | — | Alkali-resistant castables or bricks, anti-build-up castables, lightweight insulation |
| CalcinerExternal system | — | — | Alkali-resistant castables or bricks, anti-build-up castables, lightweight insulation |
| Tertiary air ductExternal system | — | — | Alkali-resistant or wear-resistant bricks, castables at bends, calcium-silicate board backing |
| Kiln hoodExternal system | — | — | Low-cement high-alumina or corundum-mullite castables with anchors |
| Burner pipeExternal system | — | — | Burner-pipe castable with steel fibres |
| Grate coolerExternal system | — | — | Hot end: high-strength wear-resistant castables, SiC castables or wear-resistant bricks; side walls, curb walls and bull nose: wear-resistant castables or precast shapes |
Lime rotary kiln
Calcining at approx. 1100–1350 ℃ class with practically no protective coating; abrasion, thermal shock, chemical attack (e.g. sulphur) and ring formation dominate.
| Zone | Jinxing products |
|---|---|
| High-temperature / burning zone |
|
| Transition zone | |
| Preheating and cooling zones |
Magnesium-metal (dolomite) rotary kiln
Calcining at approx. 1100–1250 ℃ class; abrasion, thermal shock and dust erosion dominate.
| Zone | Jinxing products |
|---|---|
| High-temperature / burning zone | |
| Transition zone | |
| Preheating and cooling zones |
Zinc-oxide (Waelz) kiln
Approx. 1100–1300 ℃ class under strongly reducing conditions with Zn/Pb vapour, FeO slag and alkali chlorides; chemical attack, ring formation, abrasion and thermal shock combine, and conditions vary widely.
| Zone | Jinxing products |
|---|---|
| Burning / reaction zone |
|
| Secondary high-temperature zone | |
| Preheating and cooling zones |
Waste-incineration rotary kiln
Approx. 850–1250 ℃ class with Cl, S, alkalis and molten ash, and frequent thermal cycling; slag attack, chlorine corrosion, thermal shock and impact abrasion combine.
| Zone | Jinxing products |
|---|---|
| High-temperature zone | |
| Secondary high-temperature zone | |
| Preheating and cooling zones |
Bauxite / alumina rotary kiln
Bauxite calcining kilns and alumina clinker kilns differ: the former run hotter in the high-temperature zone, the latter add alkali (Na₂O) attack.
| Zone | Jinxing products |
|---|---|
| High-temperature and transition zones (bauxite) | |
| Preheating and cooling zones (alumina) |