The main performance of the kiln is mainly determined by the technical and economical performance of the refractories, which directly affects the investment cost, work performance, thermal efficiency, and energy consumption of the kiln. The general principle of choosing refractory materials:

1. The furnace performance and thermal characteristics. Kilns with intermittent work should use materials with low heat capacity.
2. The safe use of materials temperature, thermal conductivity, high temperature strength, chemical stability.
3. The use of life.
4. Investment costs and operating maintenance costs.

In general, heavy refractory materials focus on a certain technical performance index, such as high temperature stability, chemical stability, etc.; lightweight insulation materials pay more attention to the integrated technical and economic indicators of input and operation.

When using lightweight insulation materials, it is generally determined by the thermal conductivity of the insulation material (λ) and the cost per unit volume of insulation material (Ρ). The smaller the value of the product of “λΡ”, the better. The small value of the thermal conductivity indicates that the thermal insulation material has a good thermal insulation effect and the energy cost during operation is low. The low cost per unit volume of insulation material indicates that the investment cost is low and has a good investment and economic effect. It can be selected by coordinate graphical method. The abscissa is the working temperature and the ordinate is the product of (λΡ). The curve of each material is intercepted by the safe use temperature of the material, and the material with good technical and economic performance is selected.