Compared to the traditional processing, modern glass making technology has undergone a qualitative change in efficiency, energy consumption and quality. Furnaces, as the core equipment of glass making, continue to be improved. The rapid development of glass making promotes the development of refractories.
Refractories used in the glass furnace are required to withstand higher temperature, sharper temperature changes, more serious chemical corrosion and severer stress damage. The common refractories used in the glass furnace are as followings:
1) Fused cast
AZS and fused cast high zircon block
For fused cast AZS block, it is important to improve its corrosion resistance and wear resistance. Besides the oxidizing melting method, reducing the carbon content to 0.005 and improving the exudation temperature of glass phase to 1450?, the casting method and annealing method are also improved to improve the quality and properties of fused cast AZS.
Fused cast high zircon block with more than 90% ZrO2 has excellent thermal shock resistance and low potential of pollution to glass.
2) Chrome brick
Dense chrome bricks made by isostatic pressing are used in the walls, throat and other severely corroded areas in the E or C glass furnaces. Its service life can be as long as 6-7 years. Cr2O3 are added into fused cast AZS block to make fused cast AZSC block (Al2O3-ZrO2-SiO2-Cr2O3). At high temperature, Cr2O3 can from solid solution with Al2O3. Since Cr2O3 has a high melting point, it can improve the viscosity of glass phase and the exudation temperature of glass phase and improve the corrosion resistance to glass.
3) Basic brick
High pure direct bond basic bricks fired at 1800? are widely used in the walls of regerators and crown.
4) Olivine magnesia brick
Since olivine bonding phase has high corrosion resistance, increasing the olivine content in the bonding phase of magnesia can greatly improve the corrosion resistance of magnesia brick. Olivine magnesia brick is cheap and widely used in the middle part of the checker work.
5) Celsian olivine brick
Olivine has good corrosion resistance but insufficient thermal shock resistance. Celsian can significantly improve the thermal shock resistance. Celsian is formed in the firing process, and exists only in the binding matrix phase. Celsian can resist the corrosion of alkali and sulphate.
6) Monolithic materials
The application of monolithic materials in the glass industry can greatly reduce the joints of furnace structure and the cold repair time.