New challenges are raised to refractory materials in the crown and superstructure of oxy-fuel fired glass melting furnaces in comparison to air-fuel fired glass melting furnaces. In glass melting furnaces which are oxy-fuel fired, the water steam partial pressure above the melt increases very strongly. In the case of soda-lime-silica glass melts together with the water steam partial pressure the alkaline hydroxide partial pressure increases with a factor of three in comparison to an air-fuel firing system. This leads to an aggressive action on the refractory lining in the crown and superstructure. After extensive thermodynamic calculations and laboratory tests a pure spinel refractory material (MgO.Al203) was developed for the application in the crown and superstructure of oxy-fuel fired glass melting furnaces.
