What is fire brick configuration for the nowadays large type of cement rotary kiln?

In the nowadays large type of cement rotary kiln configuration, the fire brick is mainly configured as follows:

1. Front Kiln mouth: Special refractory castable for kiln mouth;

2. Lower transition zone: Special Si-Mullite brick;

3.Sintering zone: MgO-Fe2O3 Spinel brick;

4 Upper transition zone: 1680Si-Mullite brick;

5.Preheating zone: 1650 Si-Mullite Birck;

6.Safety zone: Low thermal conductivity alkali-resisting mullite brick;

7. Back kiln mouth: FA-75 stainless steel strength refractory castable.