Design Considerations and Field Results for Back-Cast Refractory Tile Systems in Waste-to-Energy Plants

摘要

A recent trend in the use of refractory materials for tube wall protection in waste-to-energy boilers has included a combination of castable silicon carbide cement and refractory tiles. The system is installed by first dry-setting the silicon carbide refractory tiles, then casting a selfflowing silicon carbide cement behind the tiles. This system provides a double layer of refractory protection, as well as increased heat flow through the refractory that leads to lower temperatures in the upper boiler sections and less slagging on the refractory in the hot zones.These installations are widely used in Europe and are now gaining experience in the United States. Design considerations included heat transfer calculations, thermal expansion considerations and tile attachment and fit schemes. Results to date have been very favorable in terms of refractory life and boiler performance.