- Time:Sep 06, 2023
Reasonable refractory configuration is the key to high efficiency. The selection of refractory materials needs to consider kiln age, capital budget, production cycle and the status of refractory materials, etc., so that the kiln can operate most efficiently, maximize safety, and protect and extend the life of the cylinder in the most economical form.
1. Magnesia-aluminum spinel bricks or silicon molybdenum bricks should be used for the parts that must have a stable kiln skin in the transition zone on both sides
2. The firing zone has the highest temperature, using magnesia-iron spinel bricks
3. Anti-flaking high-alumina bricks are used in the decomposition zone, but if some parts are eroded quickly and the life is too short, composite structure silica bricks with strong corrosion resistance can also be used
4. The surface temperature of the lining of the preheater and calciner system is less than 1200°C, and high-strength alkali-resistant bricks are used. If the production capacity is large and the temperature of the calciner is higher than 1200°C, replace it with anti-stripping high-alumina bricks. In addition to the working layer in the fixed equipment, it is necessary to increase the heat insulation layer, and uniformly use calcium silicate boards as insulation. The shrinkage of the calciner and the gooseneck are constructed with high-alumina castables.
5. Use anti-skinning castables at the kiln tail shrinkage and the slope of the smoke chamber.
6. When the kiln hood is overhauled, the maintenance time can reach more than 24 hours, use high-alumina and low-cement castables, and when the kiln hood is repaired, the maintenance time is not enough, use high-aluminum or wear-resistant castables.
7. High-strength alkali-resistant castables and steel fiber castables are used in the middle and low-temperature areas of the grate cooler.
8. For parts such as the front wall of the grate cooler, the tertiary air duct of the grate cooler, and the bend of the tertiary air duct of the calciner, due to the high temperature and high wear resistance requirements of these parts, high-strength wear-resistant castables are selected, and the tertiary air duct is used at the same time. The part where the pipe enters the calciner can be built with anti-stripping high-alumina bricks.
9. Calcium silicate board is used for the thermal insulation layer of the tertiary air duct, and wear-resistant silica molybdenum bricks are used for the lining of the working layer.
10. Special coal injection pipe castables are selected for coal injection pipes; kiln mouth castables are used for overhaul of the kiln mouth, and the overall operation time is guaranteed to be more than 8 months.
11. When the castables in other high-temperature parts cannot meet the minimum 24-hour requirements for temporary repair or maintenance conditions, use castables with PA80 glue, that is, general-purpose PA80 series products, and use PA80 glue (phosphoric acid) as a binder. PA-80 (1 2 3 series) are high alumina, wear-resistant and corundum mullite respectively.
12. By adopting new materials and new technologies, the cost performance of refractory materials can be improved. This includes not only considering economic benefits, but also focusing on environmental friendliness and reducing usage costs. One of the methods is to carry out chromium-free innovation, reduce the use of toxic chromium compounds, reduce the risk of environmental pollution, and meet the environmental protection requirements for refractory materials.
13. The scattered bricks of magnesia-iron spinel bricks and anti-stripping high-alumina bricks returned from the rotary kiln are recommended as the main materials consumed by the straight wall of the grate cooler, and the construction adopts a brick-concrete frame structure. During the construction of large-area castables on low walls, slopes and other parts of grate coolers, it is encouraged to fill loose bricks returned from the rotary kiln, mainly anti-stripping high-alumina bricks.
Zone Division for Different Capacities of Cement Kilns:
6000 t/d Line (Ф5.2×72m)
5000t/dLine(Ф4.8×74m)
3200t/dLine(Ф4.3×66m)
2500t/dLine(Ф4×60m)
ZoneDivisionandBrickConfigurationforCementRotaryKilns:
