Magnesite spinel brick: cao-al2o3-fe2o3 system compound is formed with cement clinker in use. Fe2O3 component diffusion and expansion of reaction site can make kiln skin stable. Advantages: Fe2O3 has the advantages of advanced bonding structure, which can improve the anti peeling performance and adhesion performance when hanging kiln skin. Disadvantages: high temperature resistance, erosion resistance and poor oxidation and reduction performance. The upper transition zone kiln brick of cement kiln has no kiln skin protection, high temperature of the barrel and quick damage, which affects the kiln system operating rate.
Magnesia alumina spinel: high thermal conductivity and high coal consumption. Although the performance of hanging kiln skin is good, the price is expensive, and the disadvantage is that it is not resistant to ablation and sensitive to the change of atmosphere. When contact with cement clinker, Cao in clinker will interact with Fe2O3 in magnesite brick, and the melting point of C2F and other impurities is low, so the magnesium carbide has a good wetting effect. Because of the protection of kiln skin, the magnesia iron brick avoids the disadvantages of poor burning erosion ability and sensitivity to the change of atmosphere, and has obtained a long life. The surface phase of cement clinker is the result of kiln skin pulverization, kiln skin and refractory falling off.
Among all the refractory materials, the best brick with hanging kiln skin is magnesite spinel brick, cement clinker and spinel brick react, and b-c2s is formed in the kiln skin. This composition has a great relationship with the stability of kiln skin. The darker part of kiln skin is refractory brick, the lighter part is cement clinker, cement clinker and refractory are closely bonded together, and liquid phase has penetrated into the refractory through the boundary of magnesite in cement clinker.
