Anti-flaking high-alumina bricks are fired refractory bricks made of special-grade high-alumina bauxite clinker and ZrO2-containing components, which are made by high-pressure molding according to a specific ratio. Anti-stripping high-alumina bricks have strong anti-stripping ability, high refractoriness, good cracking resistance, and strong corrosion resistance. At the same time, it also has the properties of anti-corrosion of potassium, sodium, sulfur, chlorine, and alkaline salt, and low thermal conductivity. It is an ideal material for the transition zone and decomposition zone of a cement kiln, and it can also be used for the kiln door cover, cooler and other parts of the cement kiln. For now, anti-flaking high-alumina bricks are mainly used in cement kilns.
Application of Anti-stripping High Alumina Bricks in the Sintering Zone of Wet Short Kiln
Due to the insufficient pre-calcination capacity of the wet short kiln, the raw material needs to be calcined in a high-temperature slow kiln (kiln speed at 1r/min) in the firing zone. Therefore, the heat load of the firing zone is high, and the kiln lining period is short. Over the years, high-alumina bricks, unfired magnesia-chrome bricks, and ordinary sintered magnesia-chrome bricks have been used as refractory materials in the firing zone, and the service life is about 120-180d, which is far behind wet-process long kilns and dry-process kilns. Combined with the status of the process and equipment, the magnesia-chrome bricks were replaced by anti-stripping high-alumina bricks in the firing zones of the two wet-process short kilns, and the kiln operating periods reached 468d and 291d respectively.
Application of Spalling-Resistant High-Alumina Bricks for Firing Zone in Wet Short Kiln
1) 80 anti-flaking high alumina bricks use the mechanism of phase transformation toughening to improve the thermal shock stability of the bricks by adding zircon. Its resistance to rapid cooling and rapid heating is more than 20 times, which is far greater than about 8 times of magnesia-chrome bricks. Therefore, it is determined that the brick has an excellent ability to resist local thermal stress, and it will not burst due to the local heating and cooling of the fire brick. Therefore, this brick is most suitable for use in cement kilns with frequent start and stop times and large temperature fluctuations in the kiln.
2) 80 anti-flaking high-alumina bricks have better hanging kiln skin performance because Al2O3 can form C3A low melting point minerals with clinker. Once the kiln skin is formed, the kiln skin and fire bricks are firmly combined, and the kiln skin is relatively stable.
3) 80 anti-stripping high-alumina bricks increase the viscosity of the glass phase due to the introduction of ZrO2. It prevents further infiltration of K+ and Na+ in cement clinker and gas phase to form kalephine and so on. Thereby curbing the expansion and cracking of bricks, and having good chemical corrosion resistance.
4) From the physical and chemical indicators of bricks, the load softening point of anti-stripping high-alumina bricks is slightly lower than that of magnesia-chrome bricks by 30 °C. The thermal shock stability is better than that of magnesia-chrome bricks, and the compressive strength at room temperature is more than 60MPa higher than that of magnesia-chrome bricks. This reflects that the internal structure of the anti-stripping brick is better. In terms of price, the anti-flaking high-alumina brick is 300 yuan/t lower than the magnesia-chrome brick. Especially in the current situation where many ordinary magnesia-chrome bricks are of poor quality. Anti-flaking high-alumina refractory bricks are used in small and medium-sized rotary kilns with low thermal load and high mechanical stress, which has a longer cycle and better economic benefits than ordinary magnesia-chrome bricks.
5) The disadvantage of anti-stripping high alumina bricks is that the softening point under load is low. Therefore, it is not suitable for use in the firing zone of a large rotary kiln with a high heat load, and attention should be paid to the use in the firing zone. Anti-flaking high-alumina bricks, the temperature when hanging the kiln skin is lower than that of magnesia-chrome bricks.
6) Promote the use of anti-flaking high-alumina refractory bricks in the firing zone of small and medium-sized rotary kilns.
Application Furnace Type and Use Position of Anti-Stripping High Alumina Refractory Bricks
The anti-shedding high alumina brick has regular shape, smooth flow path and accurate size. The refractory products of high alumina bricks for metallurgical cast steel are suitable for various steel types (including stainless steel and various alloy steels). All kinds of funnel bricks, cast pipe bricks, base bricks, straight flow steel bricks, single hole flow steel bricks, second and third flow steel bricks, flow steel tail bricks and ingot mold bottom bricks for flat pouring steel. The product has high refractoriness, good crack resistance and strong corrosion resistance. The appearance is regular, the channel is smooth, the size is accurate, and the variety is complete.
Production of ladle lining bricks, curved lining bricks, fired and unfired plug bricks, sprue bricks, seat bricks and sleeve bricks of cast steel in ladles. Excellent raw materials and common technology make the product have good high-temperature physical and chemical properties, resistance to erosion, no deformation, and no shedding.
The finished fired refractory bricks are produced by high-pressure molding according to a specific ratio. The product has strong anti-shedding ability, and also has the properties of anti-corrosion of potassium, sodium, sulfur, fluorine and alkaline salt, low thermal conductivity, etc. It is an ideal material for the transition zone and decomposition zone of cement kiln. The vertical wall of the three-dimensional lime kiln is generally made of anti-shedding high-alumina bricks, and the special parts are made of phosphate ramming material or castable. Use high-strength clay bricks for non-critical parts.
Contact Rongsheng high-alumina refractory brick manufacturers to get the price information and refractory configuration plans for free.