In order to study the application of high-alumina homogeneous materials in wear-resistant castables for garbage incinerators, it is first necessary to understand the characteristics and requirements of the wear-resistant castables.
Wear-resistant castables for waste incinerators usually require the following characteristics:
(1) High strength and good wear resistance to resist the abrasion of solid materials and the erosion of hot air flow;
(2) Good volume stability and acid resistance to resist the corrosion of acidic substances in the furnace;
(3) Good thermal shock stability to resist the destruction of materials caused by changes in furnace temperature;
(4) Good resistance to CO corrosion, to avoid the furnace lining from cracking due to CO corrosion.
Moreover, with the trend toward large-scale incinerators, the technical requirements for refractory materials for incinerators are becoming stricter and stricter.
Generally, the main raw materials of high-alumina wear-resistant castables for incinerators are mostly traditional high-alumina bauxite clinker. Due to the difference of production area, the composition of high-alumina bauxite raw materials is different, especially the type and content of impurities are quite different. Due to the influence of the firing process and manual picking process, high-bauxite clinker has the characteristics of insufficient quality, insufficient processing, and poor uniformity, which seriously affects the stability of wear-resistant castable performance indicators and the uniformity of damage rate , There will even be problems such as local wear, penetration and rapid erosion of the high-temperature furnace lining, which seriously reduces the service life of the wear-resistant castable and the utilization factor of the high-temperature furnace.
Homogeneous materials are made through homogenization process and appropriate high temperature calcination, so as to achieve the stability and uniformity of structure, performance and quality, and avoid concentration of impurities. In the "Eighth Five-Year Plan" research, according to the alumina content and impurity characteristics of my country's bauxite, the research and development of high bauxite homogenizing materials have been carried out, and the homogeneous materials with Al2O3 content of 70%~90% have been gradually developed. , The bulk density is 2.9~3.5g·cm3. The synthetic homogeneous material has the characteristics of low porosity, low water absorption, high bulk density and high uniformity.
In the wear-resistant castable for waste incinerators, the introduction of homogeneous materials, due to the characteristics of good homogeneity and high compactness of the homogeneous materials, not only reduces the apparent porosity of the material, but also improves the conventional physical properties such as the strength and wear resistance of the material , And improve the performance of the wear-resistant castable against fly ash erosion and penetration, can prolong the service life of the wear-resistant castable at key parts of the incinerator, and ensure the stable operation of the incinerator.
