Calcium silicate insulation material have important applications in circulating fluidized bed (CFB) boilers and supporting equipment, mainly due to their high temperature resistance, thermal shock resistance and erosion resistance, which can significantly improve the thermal efficiency and operation stability of equipment. The following are its specific application directions and advantages:
1. Insulation of furnace and cyclone separator
The operating temperature of the circulating fluidized bed furnace is usually 800-950℃. Calcium silicate insulation material (xonotlite type, temperature resistance 1000℃) as the inner lining can effectively reduce heat loss and reduce the outer wall temperature to below 50℃. Its low thermal conductivity (0.06-0.09 W/(m·K)) can improve combustion efficiency and resist the erosion and wear of high-concentration ash particles in the furnace.
2. Insulation of return feeder and flue
The return feed system needs to withstand frequent temperature fluctuations (300-900℃). Calcium silicate material has a low thermal expansion coefficient (≤0.5%) and strong thermal shock resistance, which can avoid cracking caused by thermal stress. In addition, its resistance to sulfide corrosion (pH tolerance 2-12) can extend the life of the flue and reduce acid gas erosion.
3. Energy saving and cost reduction advantages
Compared with traditional ceramic fibers, the thickness of the calcium silicate insulation layer is reduced by 30%-40%, heat loss is reduced by more than 15%, and fuel consumption is reduced by about 3%-5%. Its density (200-350 kg/m³) and strength (compression resistance ≥1.5MPa) are balanced, combining lightweight and structural stability, reducing the load on the supporting structure.
4. Adaptability to special scenarios
In response to the anti-coking needs of CFB boilers, the surface of calcium silicate can be coated with silicon carbide coating to improve the anti-slagging performance; in the wet desulfurization area, hydrophobic calcium silicate (water absorption rate ≤5%) can prevent the insulation layer from failing due to moisture absorption.
