Utilization of coal fly ash as a raw material for refractory production

In this research, fireclay bricks were produced using fire clay and coal fly ash as raw materials. Coal fly ash was added to the mixture from 10-50 wt%. The disk shape samples were sintered at the temperatures of 1,100- 1,400 degrees C. The mechanical property, thermal property, phase structure and microstructure of the fireclay bricks were studied. It was found that coal fly ash can be used in the fabrication of fireclay bricks. The lower linear shrinkage and lower thermal conductivity were obtained as the higher amount of coal fly ash was added. However, bulk density and strength were lower in the samples contained coal fly ash. The effects of coal fly ash on the phase structure and microstructure of the fireclay bricks were investigated using XRD and SEM technique, respectively. Mullite phase decreased with the higher coal fly ash added, whereas anorthite phase increased.