Production of glass-ceramics from coal ashes

Coal fly ashes produced by an extinguished power plant in the north of Portugal have been melted with addition of CaCO3 and Na2CO3 to obtain glasses. One of the formulated compositions was selected for further studies and it was possible to manufacture glass-ceramics by crystallising the parent glass through adequate time–temperature schedules. The macroscopic appearance, microstructure, mechanical, thermal and chemical properties indicated that these materials are quite attractive for cladding applications, exhibiting in some cases better performances than the conventional ceramic tiles.