Effects of Nano-SiO2 on tiles manufactured with clay and incinerated sewage sludge ash

In an effort to extend the reutilization of sewage sludge ash and improve the properties of sludge ash tiles, nano-SiO2 was applied as an additive to sludge ash tiles. Improvements in the tiles were evaluated by factors such as the amount of clay that was replaced by incinerated sewage sludge ash, the quantity of nano-SO2 added, and the kiln temperatures. Furthermore, the effects of nano-SiO2 on the structure and mechanism of sludge ash tiles were studied from both microscopic and macroscopic views. Results indicate that the bending strength of sludge ash tiles increased with increased amounts of nano-SiO2. However, due to brittle structures formed on the surfaces of tile bodies at temperature of 1,150 degrees C or higher, reductions in bending strength were correlated with increasing amounts of nano-SiO2 added.