The refractory materials used in glass kiln regenerator mainly include lattice body, grate arch, regenerator top arch, side wall and middle partition wall. The temperature of the regenerator brick changes with time, the temperature fluctuation is large, and the gas is complex. It mainly bears losses from three aspects: thermal shock, chemical erosion and mechanical stress. Thermal shock can easily cause the brick body to melt, soften and generate thermal stress, resulting in cracking of the brick body, which mainly occurs in the upper part of the lattice brick. Chemical erosion is the erosion of the above-mentioned solid powder and gas and the contact reaction between lattice bricks of different properties, which will cause the brick body to melt into liquid phase, crystal transformation, structural cracking, peeling, etc., which mainly occurs in the middle and upper part of the regenerator. Mechanical stress is mass load. The total mass of the lattice bricks in a regenerator is about 100t, so the load of the bottom lattice bricks is large, and it must withstand the alternating cold and hot effects of the reversing operation. Therefore, it is required to select dense, thermal shock-resistant and load-bearing refractory materials.
At present, there are two main options for the selection of checker bricks for regenerators:
- Alkaline brick option - In this option, the top checker bricks of the regenerator are made of directly bonded high-purity magnesia bricks, the upper layer is made of ordinary fired magnesia bricks, the middle layer is made of sulfate-resistant magnesia chrome bricks or forsterite bricks, the lower layer is made of low-porosity clay bricks, and the transition material between magnesia bricks and clay bricks is made of anti-stripping high-alumina bricks.
- Fused zirconium brick option - The entire lattice body of the regenerator uses the same cross-shaped fused zirconium corundum checker bricks (ER-1681). It is reported that fused β-alumina materials have recently been used as the top checker bricks.
The top arch of the regenerator is often made of fused AZS bricks, directly bonded magnesia bricks or silica bricks. The upper layer of the side walls and partition walls uses magnesia bricks, the middle layer uses magnesia bricks or low-porosity clay bricks, and the lower layer uses low-porosity clay bricks. Low-porosity clay bricks are used for the grate arch.
HOME