Selection Scheme and Core Advantages of Mullite Insulating Bricks for the Outer Walls of Glass Furnace Regenerator Chambers

Suitable thermal insulation performance, reducing energy loss
The regenerator chamber recovers waste heat from exhaust gas through checker bricks, and heat dissipation from the outer wall is one of the main sources of energy loss. Mullite insulating bricks use mullite (3Al₂O₃・2SiO₂) as the main crystalline phase. Its unique porous structure (apparent porosity 45%-55%) effectively blocks heat conduction paths. At 800℃, the thermal conductivity is only 1/3 of that of ordinary clay bricks (ordinary clay bricks have a thermal conductivity of 0.8-1.0W/(m・K)), which can control the outer wall temperature within 60℃, reducing heat loss by more than 40%, significantly improving furnace thermal efficiency and reducing fuel consumption.

Strong high-temperature structural stability and sufficient load-bearing capacity
The outer wall of the regenerator chamber is subjected to high-temperature radiation of approximately 1000℃ for a long time and needs to bear the weight of the upper masonry. The mullite crystal structure is dense and stable, and does not easily soften or creep at high temperatures. At the same time, its thermal expansion coefficient is moderate and matches the thermal expansion characteristics of the main refractory bricks of the regenerator chamber (such as high-alumina bricks and magnesia bricks), avoiding gaps or structural stress caused by thermal expansion and contraction after masonry, ensuring the integrity of the wall.

Excellent thermal shock resistance, suitable for cyclic operating conditions
Glass furnace regenerators require frequent switching between "heat storage - heat release" modes, resulting in drastic temperature fluctuations (single fluctuations can exceed 500℃). Ordinary insulating bricks (such as diatomaceous earth bricks and perlite bricks) are prone to cracking due to thermal shock. Mullite insulating bricks, through optimized particle size distribution and pore structure, have a thermal shock resistance (1100℃ water cooling - air cooling cycle) of 5-7 cycles, enabling them to withstand frequent temperature changes without cracking, preventing insulation failure or furnace gas leakage due to wall damage.

Outstanding weather resistance and durability, reducing maintenance costs
In outdoor environments, the mullite crystal phase of mullite insulating bricks has strong chemical stability and does not react with water, carbon dioxide, and other media. Compared with traditional lightweight insulating bricks, its resistance to weathering and pulverization is stronger, 2-3 times that of ordinary lightweight insulating bricks.

Environmentally compliant and excellent construction adaptability
Mullite insulating bricks do not contain harmful substances such as chromium and lead, and there are no pollutant emissions during production and use, complying with current environmental emission standards; its moderate density (1.2-1.5g/cm³) makes it easier to handle and transport compared to high-density refractory bricks, resulting in high construction efficiency. The bricks have regular dimensions, and the mortar joints are easy to control (recommended joint thickness 3-5mm), effectively ensuring wall airtightness and preventing high-temperature gas leakage.

Although ceramic fiber bricks have better insulation performance, they have low compressive strength and are prone to moisture absorption, making them unsuitable for the main load-bearing structure of the outer wall; diatomaceous earth insulating bricks have low temperature resistance and poor thermal shock resistance, and are only suitable for auxiliary insulation in the lower low-temperature area (<900℃) of the regenerator, and cannot meet the core requirements of the outer wall.