Cement kiln is a commonly used equipment in the cement production process, which is mainly used for calcining raw materials at high temperature, volatilizing moisture, organic and inorganic impurities in the raw materials, and finally obtaining cement clinker. Cement kiln type has experienced the development of vertical kiln - mechanical vertical kiln - wet rotary kiln - new dry rotary kiln several stages, dry production of cement is currently the most mature and stable cement production process.
New dry-process cement production line mainly consists of preheater, decomposition furnace, rotary kiln, grate cooler, three air ducts are composed of several systems, their respective areas have different working characteristics and use of the environment, new dry-process rotary kiln due to process characteristics caused by alkali, sulfur and other volatile components of the enrichment, the kiln temperature, kiln diameter increased, kiln speed accelerated, the structure of the complexity of the reason, resulting in the refractory material of the chemical attack, high temperature damage, mechanical stress and thermal stress and other comprehensive crushing effect is greater than the traditional kiln. Stress and thermal stress and other comprehensive crushing effect than the traditional kiln is greater, coupled with the current higher environmental protection and energy saving requirements, should be based on the characteristics of the working conditions, each region should be selected from different refractory materials.
Common refractory materials include: high alumina bricks, silica mo red bricks, magnesia-aluminum spinel bricks, magnesia-iron spinel bricks, corundum wear-resistant castable, coal injection pipe castable, steel fiber reinforced castable and so on.
| Item | High aluminum brick | Silmo Red Brick | Magnesium-aluminum Spinel brick | Magnesium-iron Spinel brick | Corundum wear-resistant castable | Coal Injection Pipe Casting material |
Steel Fiber Reinforced castable |
| Al2O3；% | ≥65 | ≥60 | 10-13 | 3-5 | ≥80 | ≥70 | ≥70 |
| MgO；% | / | / | ≥85 | ≥85 | / | / | / |
| SiC+SiO2；% | / | ≥30 | / | / | / | ≥25 | / |
| Fe2O3；% | / | / | / | 3-4 | / | / | / |
| Refractoriness；℃ | ≥1700 | ≥1770 | ≥1790 | ≥1790 | ≥1790 | ≥1790 | ≥1770 |
| Apparent porosity；% | ≤24 | ≤20 | ≤18 | ≤18 | / | / | / |
| Bulk density；g/cm3 | ≥2.3 | ≥2.6 | ≥2.9 | ≥2.9 | ≥2.8 | ≥2.7 | ≥2.5 |
| Cold crushing strength；Mpa | ≥45 | ≥80 | ≥60 | ≥70 | ≥80 | ≥70 | ≥70 |
| 0.2MPa refractoriness-under-load/℃ | ≥1400 | ≥1600 | ≥1650 | ≥1700 | / | / | / |
| Thermal shock stability; times (1100℃, water cooling) | / | ≥15 | ≥6 | ≥10 | / | ≥15 | / |
| Application | Preheating zone/sadety zone | Lower transition zone/Upper transition zone | Calcining zone | Calcining zone | Rear kilneye/Front kilneye | Burners | Decomposer |
Lime kiln
Ladle
Pretreatment of Liquid Iron
Hot blast stove
Refractory materials for casting
